JP6859594B2 - Liquid injection head and liquid injection head unit - Google Patents

Description

The present invention relates to a liquid injection head that drives a driving element such as a piezoelectric element to inject liquid from a nozzle, and a liquid injection head unit including a plurality of these.

As a liquid injection device equipped with a liquid injection head, for example, there are image recording devices such as an inkjet printer and an inkjet plotter, but recently, a feature that a very small amount of liquid can be accurately landed at a predetermined position. It is also applied to various manufacturing equipment by making the best use of. For example, a display manufacturing device that manufactures a color filter such as a liquid crystal display, an electrode forming device that forms an electrode such as an organic EL (Electro Luminescence) display or a FED (surface emitting display), and a chip that manufactures a biochip (biochemical element). It is applied to manufacturing equipment. Then, the recording head for the image recording device injects liquid ink, and the color material injecting head for the display manufacturing device injects solutions of each color material of R (Red), G (Green), and B (Blue). Further, the electrode material injection head for the electrode forming apparatus injects a liquid electrode material, and the bioorganic material injection head for the chip manufacturing apparatus injects a solution of the bioorganic substance.

The above-mentioned liquid injection head has a plurality of nozzles, a pressure chamber formed for each nozzle, a common liquid chamber (also referred to as a reservoir or a manifold) for supplying liquid to each pressure chamber, and a pressure fluctuation in the liquid in each pressure chamber. It is provided with a driving element such as a piezoelectric element that causes the above. A part of the surface partitioning the common liquid chamber is formed by an elastic membrane and is configured to absorb internal pressure fluctuations. The compliance space formed on the opposite side of the membrane from the common liquid chamber is open to the atmosphere through a flow path having high flow path resistance. Further, the piezoelectric element accommodating space for accommodating the driving element is also open to the atmosphere so as to have the same humidity as the outside air (for example, Patent Document 1).

Further, from the viewpoint of miniaturization, a configuration is also adopted in which the compliance space and the piezoelectric element accommodating space are connected by a flow path and are collectively opened to the atmosphere. For example, in the conventional liquid injection head 91 shown in FIG. 19, two compliance spaces 92a and 92b and two piezoelectric element accommodating spaces 93a and 93b are opened to the atmosphere through one air opening port 94 formed on the upper surface. ing. Specifically, the compliance space 92a on one side and the piezoelectric element accommodating space 93a on one side corresponding to the nozzle row on one side (right side in FIG. 19) of the two rows of nozzles are inside the liquid injection head 91. It communicates with the compliance space 92b on the other side corresponding to the nozzle row on the other side (left side in FIG. 19) through the flow path 95. Further, the piezoelectric element accommodating space 93b on the other side corresponding to the nozzle row on the other side is also connected to the internal flow path 95 and communicated with the compliance space 92b on the other side. The compliance space 92b on the other side is open to the atmosphere via a common atmospheric opening path 96 communicating with the atmospheric opening 94. As a result, the two compliance spaces 92a and 92b and the two piezoelectric element accommodating spaces 93a and 93b are opened to the atmosphere from the atmosphere opening 94 common to them.

Japanese Unexamined Patent Publication No. 2005-131888

By the way, in the conventional liquid injection head 91, there is a possibility that the moisture (or moisture) that has penetrated through the membrane and entered the compliance spaces 92a and 92b from the common liquid chamber may enter the piezoelectric element accommodating spaces 93a and 93b. It was. In particular, since the compliance space 92a on one side is communicated with the common air opening path 96 via the internal flow path 95, it is difficult for moisture to escape to the outside of the liquid injection head 91. Therefore, moisture easily enters the piezoelectric element accommodating space 93a on one side. When the humidity invades the piezoelectric element accommodating space and the humidity in the piezoelectric element accommodating space rises in this way, moisture adheres to the piezoelectric element accommodated in the piezoelectric element accommodating space due to the occurrence of dew condensation or the like, and the piezoelectric element is accommodated. There was a risk that the element would be destroyed. Further, as in Patent Document 1, it is conceivable that the compliance space and the piezoelectric element accommodating space are individually opened to the atmosphere, but even if such a configuration is made, it is not sufficient. That is, since the compliance space and the sealing space are open to the atmosphere inside the housing of the liquid injection device, which tends to be in a humid environment, even if these are individually opened to the atmosphere, moisture can sufficiently enter the piezoelectric element accommodating space. There is a risk that it cannot be suppressed.

The present invention has been made in view of such circumstances, and an object of the present invention is a liquid injection head capable of suppressing the invasion of moisture into a space sensitive to moisture such as a space for accommodating a piezoelectric element. , And to provide a liquid injection head unit.

The liquid injection head of the present invention has been proposed in order to achieve the above object, and includes a nozzle opened on the nozzle surface and a liquid flow path communicating with the nozzle, and drives a driving element to drive the liquid injection head. A liquid injection head that injects liquid from a nozzle.
A first space isolated from the liquid flow path and
It is provided with a second space that is isolated from the liquid flow path and allows moisture to easily enter from the liquid flow path rather than the first space.
The first atmosphere opening path that opens the first space to the atmosphere is characterized in that the flow path resistance is higher than that of the second atmosphere opening path that opens the second space to the atmosphere.

According to the present invention, it is possible to suppress the invasion of water (or moisture) into the first space. For example, if the first space is a space in which the driving element is accommodated, the adhesion of water to the driving element can be suppressed, and eventually the destruction of the driving element can be suppressed.

In the above configuration, the first atmosphere opening path and the second atmosphere opening path are commonly formed from the atmosphere opening port communicating with the atmosphere to the branch in the middle.
It is desirable that the first branch flow path from the branch to the first space adopts a configuration in which the flow path resistance is higher than that of the second branch flow path from the branch to the second space.

According to this configuration, it is possible to suppress the intrusion of water from the second space into the first space. Further, since the first atmosphere opening path and the second atmosphere opening path are commonly formed from the atmosphere opening port to the branch, compared with the case where the first atmosphere opening path and the second atmosphere opening path are separately opened to the atmosphere. , The configuration of the liquid injection head can be simplified. Further, as compared with the configuration in which the first open path to the atmosphere and the second open path are opened to the atmosphere separately, it is possible to suppress a decrease in the strength of the liquid injection head.

Further, in the above configuration, it is desirable that the first branch flow path includes a partial flow path extending from the first space along the nozzle surface.

According to this configuration, even if dew condensation occurs in the first open air passage, it is possible to suppress the dew condensation from entering the first space.

Further, in the above configuration, it is desirable that at least a part of the first branch flow path adopts a configuration formed between the first space and the nozzle surface.

According to this configuration, even if dew condensation occurs in the first open air passage, it is possible to further suppress the dew condensation from entering the first space.

Further, in the above configuration, a first liquid flow path communicating with a first nozzle group composed of a plurality of nozzles and
A second liquid flow path communicating with a second nozzle group composed of a plurality of nozzles formed apart from the first nozzle group,
A first drive element group composed of drive elements provided for each nozzle of the first nozzle group, and
A second drive element group composed of drive elements provided for each nozzle of the second nozzle group, and
A first space for the first drive element group, which is a kind of the first space for accommodating the first drive element group, and
A first space for a second drive element group, which is a kind of the first space for accommodating the second drive element group, and
A second space on the side of the first liquid flow path, which is a kind of the second space, in which moisture easily enters from the first liquid flow path than the first space for the first drive element group.
It is provided with a second space on the side of the second liquid flow path, which is a kind of the second space, in which moisture easily enters from the second liquid flow path than the first space for the second drive element group.
The first atmosphere opening path on the first driving element group side that opens the first space for the first driving element group to the atmosphere, and the first atmosphere on the second driving element group side that opens the first space for the second driving element group to the atmosphere. The open path is communicated with the atmosphere through a first space open port common to the first atmospheric open path on the first drive element group side and the first atmospheric open path on the second drive element group side.
The first liquid flow path side second atmosphere opening path that opens the first liquid flow path side second space to the atmosphere and the second liquid flow path side second atmosphere opening path that opens the second liquid flow path side second space to the atmosphere It is desirable to adopt a configuration in which the first liquid flow path side second atmosphere opening path and the second liquid flow path side second atmosphere opening path are communicated with the atmosphere through a second space opening port common to the atmosphere opening port. ..

According to this configuration, the first space for the first drive element group and the first space for the second drive element group, and the second space on the first liquid flow path side and the second space on the second liquid flow path side are the liquid injection heads. Moisture (or water) from the second space on the first liquid flow path side and the second space on the second liquid flow path side to the first space for the first drive element group and the first space for the second drive element group because they are not communicated with each other. Invasion of moisture) can be suppressed. As a result, the adhesion of water to the driving element can be suppressed, and eventually the destruction of the driving element can be suppressed. Further, the first atmospheric opening path on the first driving element group side, the first atmospheric opening path on the second driving element group side, the second atmospheric opening path on the first liquid flow path side, and the second atmospheric opening path on the second liquid flow path side It is possible to suppress a decrease in the strength of the liquid injection head as compared with a configuration in which the liquid injection head is separately opened to the atmosphere.

Further, in the above configuration, the first nozzle group and the second nozzle group are arranged along the first direction.
It is desirable to adopt a configuration in which the first space opening port and the second space opening port are formed so as to be separated from each other in the first direction.

According to this configuration, it is possible to suppress a decrease in the strength of the liquid injection head. Further, from the second space on the first liquid flow path side and the second space on the second liquid flow path side, the first space and the first space for the first drive element group are passed through the air opening for the second space and the atmosphere opening for the first space. It is possible to suppress the invasion of moisture into the first space for the two drive element groups.

Further, in each of the above configurations, the first atmospheric open path on the first drive element group side is a partial flow path on the first drive element group side extending along the nozzle surface from the first space for the first drive element group. With
The first atmospheric open path on the second drive element group side adopts a configuration including a partial flow path on the second drive element group side extending from the first space for the second drive element group along the nozzle surface. Is desirable.

According to this configuration, even if dew condensation occurs in the first atmospheric open path on the first drive element group side and in the first atmospheric open path on the second drive element group side, this dew condensation is the first for the first drive element group. It is possible to suppress the invasion into the space and the first space for the second driving element group.

Further, in each of the above configurations, at least a part of the first open air path on the first drive element group side is formed between the first space for the first drive element group and the nozzle surface.
It is desirable that at least a part of the first atmospheric open path on the second drive element group side adopts a configuration formed between the first space for the second drive element group and the nozzle surface.

According to this configuration, even if dew condensation occurs in the first atmospheric open path on the first drive element group side and in the first atmospheric open path on the second drive element group side, this dew condensation is the first for the first drive element group. It is possible to further suppress the invasion into the space and the first space for the second driving element group.

The liquid injection head unit of the present invention is a liquid injection head unit including a plurality of liquid injection heads having each of the above configurations.
In the adjacent liquid injection heads, the distance between the air opening where the second space of one liquid injection head communicates with the atmosphere and the air opening where the second space of the other liquid injection head communicates with the atmosphere is The first space in the same liquid injection head is narrower than the distance between the air opening that communicates with the atmosphere and the second space that communicates with the atmosphere.

According to this configuration, it is possible to prevent moisture from entering the first space from the second space through the air opening for the second space and the air opening for the first space.

It is a perspective view explaining the structure of a printer. It is a top view of the compliance board of a recording head. FIG. 2 is a cross-sectional view taken along the line AA in FIG. FIG. 2 is a cross-sectional view taken along the line BB in FIG. FIG. 2 is a cross-sectional view taken along the line CC in FIG. It is a perspective view which passed through the inside of a recording head. It is sectional drawing of the recording head in 2nd Embodiment. It is a top view of the compliance board of the recording head in 3rd Embodiment. FIG. 8 is a cross-sectional view taken along the line DD in FIG. FIG. 8 is a cross-sectional view taken along the line EE in FIG. FIG. 8 is a cross-sectional view taken along the line FF in FIG. It is a top view of the compliance board of the recording head in 4th Embodiment. FIG. 5 is a plan view of the compliance board of the recording head in the fifth embodiment as viewed from above. FIG. 13 is a sectional view taken along line GG in FIG. FIG. 13 is a cross-sectional view taken along the line HH in FIG. It is a schematic diagram of the recording head unit in the sixth embodiment. It is a schematic diagram of the recording head unit in 7th Embodiment. It is a schematic diagram of the recording head unit in 8th Embodiment. It is a perspective view which passed through the inside of the conventional liquid injection head.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. In the embodiments described below, various limitations are given as suitable specific examples of the present invention, but the scope of the present invention is the same unless otherwise stated in the following description to limit the present invention. The mode is not limited to the above. Further, in the following description, as the liquid injection head of the present invention, an inkjet recording head (hereinafter, recording head) 3 mounted on an inkjet printer (hereinafter, printer) 1 which is a kind of liquid injection device is taken as an example. To do.

The printer 1 is a device that records an image or the like by injecting ink (a type of liquid) onto the surface of a recording medium 2 (a type of landing target) such as recording paper. The printer 1 includes a recording head 3, a carriage 4 to which the recording head 3 is attached, a carriage moving mechanism 5 for moving the carriage 4 in the main scanning direction, a transport mechanism 6 for transferring the recording medium 2 in the sub-scanning direction, and the like. There is. Here, the above ink is stored in the ink cartridge 7 as a liquid supply source. The ink cartridge 7 is detachably attached to the recording head 3. It is also possible to adopt a configuration in which the ink cartridge is arranged on the main body side of the printer and is supplied from the ink cartridge to the recording head through the ink supply tube.

The carriage moving mechanism 5 includes a timing belt 8. The timing belt 8 is driven by a pulse motor 9 such as a DC motor. Therefore, when the pulse motor 9 is operated, the carriage 4 is guided by the guide rod 10 installed on the printer 1 and reciprocates in the main scanning direction (width direction of the recording medium 2). The position of the carriage 4 in the main scanning direction is detected by a linear encoder (not shown) which is a kind of position information detecting means. The linear encoder transmits the detection signal, that is, an encoder pulse (a kind of position information) to the control unit of the printer 1.

Next, the recording head 3 will be described. FIG. 2 is a plan view of the compliance board 37 of the recording head 3 as viewed from above. FIG. 3 is a schematic representation of a cross section taken along line AA, FIG. 4 is a cross section taken along line BB, and FIG. 5 is a schematic representation of a cross section taken along line CC. Further, FIG. 6 is a perspective view through the inside of the recording head 3 for explaining the open path to the atmosphere of the piezoelectric element row accommodating spaces 46a and 46b and the compliance spaces 56a and 56b. As shown in FIG. 3 and the like, the recording head 3 in the present embodiment is laminated with a nozzle plate 23, a flow path substrate 29, a piezoelectric element 32 (a type of actuator), a sealing plate 33, a compliance substrate 37, and the like. In this state, it is attached to the head case 19. For convenience, the stacking direction of each member will be described as the vertical direction.

The flow path substrate 29 in this embodiment is a substrate made of silicon (for example, a silicon single crystal substrate) that is long along the nozzle row direction (corresponding to the first direction in the present invention). As shown in FIG. 3 and the like, the flow path substrate 29 is formed with two long communication portions 27 along the longitudinal direction of the flow path substrate 29. Each of the communicating portions 27 communicates with the penetrating portion 34 of the sealing plate 33 to form a common liquid chamber 26. Further, in the region sandwiched between the two communication portions 27 of the flow path substrate 29, a plurality of pressure chambers 30 are arranged side by side along the nozzle row direction. The rows of the pressure chambers 30 are formed in two rows corresponding to the two communication portions 27. Each pressure chamber 30 communicates with the communication portion 27 via a supply path 28 formed to have a width narrower than that of the pressure chamber 30. The rows of the pressure chambers 30 formed in the two rows are arranged with a deviation of half a pitch from each other in the nozzle row direction corresponding to the arrangement of the nozzles 24.

A nozzle plate 23 is fixed to the lower surface of the flow path substrate 29 (the surface opposite to the sealing plate 33) via an adhesive or the like. The nozzle plate 23 is made of a silicon substrate (for example, a silicon single crystal substrate), and a plurality of nozzles 24 communicating with the pressure chamber 30 are formed in each pressure chamber 30. That is, a plurality of nozzles 24 are provided in the nozzle plate 23 in a straight line (in other words, in a row) along the longitudinal direction of the nozzle plate 23. The plurality of nozzles 24 arranged side by side are provided at equal intervals from the nozzle 24 on the one end side to the nozzle 24 on the other end side at a pitch corresponding to the dot formation density. In the present embodiment, the rows of nozzles 24 separated from each other are formed in two rows corresponding to the rows of pressure chambers 30 formed in two rows. The nozzle 24 included in the row of nozzles 24 on one side (right side in FIG. 3 and the like) (hereinafter referred to as the first nozzle row 44a) and the row of nozzles 24 on the other side (left side in FIG. 3 and the like) (hereinafter referred to as the first nozzle row 44a). , The nozzles 24 included in the second nozzle row 44b) are staggered in the nozzle row direction. That is, the first nozzle row 44a and the second nozzle row 44b are arranged so as to be offset by half a pitch from each other in the nozzle row direction. The first nozzle row 44a corresponds to the first nozzle group in the present invention, and the second nozzle row 44b corresponds to the second nozzle group in the present invention. Further, the lower surface of the nozzle plate 23 (the side opposite to the flow path substrate 29) is the nozzle surface 25 in which the nozzle 24 is opened.

A diaphragm 31 is laminated on the upper surface of the flow path substrate 29 (the surface opposite to the nozzle plate 23). The diaphragm 31 is formed on, for example, an elastic film made of _{silicon dioxide (SiO 2} ) formed on the upper surface of the flow path substrate 29 (that is, a surface opposite to the sealing plate 33 side) and the elastic film. It is composed of an insulator film made of formed zirconium dioxide (ZrO _2). The diaphragm 31 seals the upper opening of the space that should be the pressure chamber 30. In other words, the upper surface of the pressure chamber 30 is partitioned by the diaphragm 31. The portion of the diaphragm 31 corresponding to the pressure chamber 30 (specifically, the upper opening of the pressure chamber 30) functions as a displacement portion that is displaced in a direction away from or close to the nozzle 24 as the piezoelectric element 32 bends and deforms. To do. The region of the diaphragm 31 corresponding to the communication portion 27 is an opening from which the diaphragm 31 has been removed.

In the region corresponding to each pressure chamber 30 on the upper surface of the diaphragm 31 (specifically, the insulating film of the diaphragm 31) (that is, the surface of the diaphragm 31 opposite to the flow path substrate 29 side), a type of driving element is used. The piezoelectric elements 32 are laminated. The piezoelectric element 32 in this embodiment is a so-called bending mode piezoelectric element. A plurality of the piezoelectric elements 32 are arranged side by side along the nozzle row direction corresponding to each nozzle 24. That is, for each of the first piezoelectric element row 45a (corresponding to the first drive element group in the present invention) composed of the piezoelectric element 32 provided for each nozzle 24 of the first nozzle row 44a and the nozzle 24 of the second nozzle row 44b. A second piezoelectric element row 45b (corresponding to the second driving element group in the present invention) composed of the provided piezoelectric element 32 is formed. Each piezoelectric element 32 is formed by, for example, sequentially laminating a lower electrode layer as an individual electrode, a piezoelectric layer, and an upper electrode layer as a common electrode in order from the top of the diaphragm 31. The lower electrode layer may be a common electrode and the upper electrode layer may be an individual electrode depending on the convenience of the drive circuit and wiring. When an electric field corresponding to the potential difference between the lower electrode layer and the upper electrode layer is applied between the lower electrode layer and the upper electrode layer, the piezoelectric element 32 configured in this way bends and deforms in a direction away from or close to the nozzle 24. Further, from each piezoelectric element 32, lead wiring (not shown) extends toward a region on the diaphragm 31 between the first piezoelectric element row 45a and the second piezoelectric element row 45b. The end of the lead wiring on the side opposite to the piezoelectric element 32 is a terminal exposed in the connection space 36, and is connected to a terminal (not shown) of the flexible substrate 35 in the connection space 36.

Further, a sealing plate 33 made of a silicon substrate (for example, a silicon single crystal substrate) is bonded to the upper surface of the diaphragm 31. The sealing plate 33 is formed with a penetrating portion 34 serving as a common liquid chamber 26, and piezoelectric element row accommodating spaces 46a and 46b (corresponding to the first space in the present invention) isolated from the penetrating portion 34. Has been done. The penetrating portion 34 is formed in a state of penetrating in the thickness direction at a position corresponding to the communicating portion 27. The penetrating portion 34 in the present embodiment is formed to be long along the nozzle row direction. The width (specifically, the dimension in the direction orthogonal to the nozzle row direction) at the upper part of the penetrating portion 34 (in other words, the portion on the head case 19 side) is the lower part of the penetrating portion 34 (in other words, the flow path substrate 29 side). It is formed wider than the width in the part). That is, the inner portion (specifically, the central side in the direction orthogonal to the nozzle row direction) in the upper portion of the penetrating portion 34 is a plate from the upper surface of the sealing plate 33 without the sealing plate 33 penetrating in the plate thickness direction. It is formed in a recessed state halfway in the thick direction. A liquid introduction path 21, which will be described later, is communicated with a portion recessed from the upper surface of the penetrating portion 34. Further, two penetration portions 34 in the present embodiment are provided corresponding to the two communication portions 27. The lower ends of the penetrating portions 34 communicate with the communicating portions 27 to form a common liquid chamber 26. That is, the penetrating portion 34 is a space constituting the upper part of the common liquid chamber 26.

The piezoelectric element row accommodating spaces 46a and 46b are formed in two rows corresponding to the rows of the piezoelectric element 32 formed in the two rows. That is, it is a kind of the first piezoelectric element row accommodation space 46a which is a kind of the first space in the present invention which accommodates the first piezoelectric element row 45a, and a kind of the first space in the present invention which accommodates the second piezoelectric element row 45b. A second piezoelectric element row accommodating space 46b is formed. Further, as shown in FIG. 2, the first piezoelectric element row accommodating space 46a and the second piezoelectric element row accommodating space 46b are formed in a long length along the nozzle array direction. The first piezoelectric element row accommodating space 46a and the second piezoelectric element row accommodating space 46b are recessed from the lower surface of the sealing plate 33 to the middle in the plate thickness direction to a size that does not hinder the displacement of the piezoelectric element 32. It is formed in a state. A part of the first piezoelectric element row accommodating space 46a and a part of the second piezoelectric element row accommodating space 46b in the present embodiment are recessed portions of the corresponding penetrating portions 34 when viewed from the upper surface of the sealing plate 33. It is formed so as to overlap with. Further, a connection space 36 in which the sealing plate 33 is removed in the plate thickness direction is formed between the first piezoelectric element row accommodating space 46a and the second piezoelectric element row accommodating space 46b. The connection space 36 communicates with the insertion space 20 described later, and an end portion of the flexible substrate 35 inserted through the insertion space 20 is arranged inside the connection space 36. The end of the flexible substrate 35 is connected to a terminal on the diaphragm 31 exposed in the connection space 36.

Further, as shown in FIGS. 2, 4 and 5, the sealing plate 33 has a first piezoelectric element corresponding to the first distribution channel in the present invention for opening the first piezoelectric element row accommodating space 46a to the atmosphere. The row-side first branch flow path 47a and the second piezoelectric element row-side first branch flow path 47b corresponding to the first flow path in the present invention for opening the second piezoelectric element row accommodation space 46b to the atmosphere are formed. .. The first piezoelectric element row-side first branch flow path 47a and the second piezoelectric element row-side first branch flow path 47b extend from the piezoelectric element row accommodation spaces 46a and 46b along the nozzle surface 25 (horizontal plane in this embodiment), respectively. The horizontal flow path 48 (corresponding to the partial flow path in the present invention) intersects the nozzle surface 25 from the end of the horizontal flow path 48 opposite to the piezoelectric element row accommodating spaces 46a and 46b (in the present embodiment). It is composed of a vertical flow path 49 extending along a direction (orthogonal). As shown in FIG. 5, the horizontal flow path 48 is formed in a state in which the open side of the groove formed on the lower surface of the sealing plate 33 is sealed by the flow path substrate 29. Further, as shown in FIG. 2, the horizontal flow path 48 extends from the other end (left side in FIG. 2) in the nozzle row direction of the piezoelectric element row accommodating spaces 46a and 46b toward the outside in the nozzle row direction. Then, after bending outward on one side in the nozzle row direction (right side in FIG. 2) and in the direction orthogonal to the nozzle row direction, it extends diagonally to a position deviated from the piezoelectric element row accommodating spaces 46a and 46. Being present. As shown in FIG. 4, the vertical flow path 49 is formed so as to penetrate the sealing plate 33 in the thickness direction, and the upper end thereof communicates with the corresponding common flow paths 51a and 51b (described later).

A compliance substrate 37 is bonded to the upper surface of the sealing plate 33. The compliance substrate 37 is a substrate that seals the upper surface of the communication portion 27 to partition the common liquid chamber 26, and includes a flexible sealing film 39 and a fixed substrate 38 made of a hard member such as metal. It consists of layers. The compliance substrate 37 in the present embodiment is joined to the upper surface of the sealing plate 33 with the sealing film 39 arranged below (that is, on the sealing plate 33 side). As shown in FIG. 3, at a position corresponding to the insertion space 20 in the compliance board 37, an opening (not shown) for communicating the insertion space 20 and the connection space 36 is formed in a state of penetrating in the thickness direction. ing. Further, as shown in FIGS. 2 and 3, a liquid introduction port 53 communicating the liquid introduction path 21 and the common liquid chamber 26 penetrates in the thickness direction at a position corresponding to the liquid introduction path 21 in the compliance substrate 37. It is formed in a state of being. As shown in FIG. 2, the liquid introduction port 53 in the present embodiment is arranged at a position overlapping the piezoelectric element row accommodating spaces 46a and 46b in a plan view. Further, as shown in FIGS. 2 and 4, at the position corresponding to the vertical flow path 49 in the compliance substrate 37, a communication port 54 for communicating the vertical flow path 49 and the common flow paths 51a and 51b is provided in the thickness direction. It is formed in a penetrating state.

In the region of the compliance substrate 37 facing the common liquid chamber 26, the region other than the periphery of the liquid introduction port 53 has the fixed substrate 38 removed and only the sealing film 39. That is, the portion from which the fixed substrate 38 has been removed is a facing space 40 facing the common liquid chamber 26 with the sealing film 39 interposed therebetween. The facing space 40 communicates with the case space 22 described later to form compliance spaces 56a and 56b (corresponding to the second space in the present invention). The portion composed of only the sealing film 39 functions as a compliance unit that absorbs the pressure fluctuation of the ink in the common liquid chamber 26. Further, as shown in FIG. 2, two portions made of only the sealing film 39 are formed corresponding to the two common liquid chambers 26, and each portion is formed long in the nozzle row direction.

As shown in FIG. 3, the head case 19 is joined to the upper surface of the compliance substrate 37 (that is, the fixed substrate 38). The head case 19 in this embodiment is a box-shaped member made of synthetic resin. An insertion space 20 which is a long space along the nozzle row direction is formed in the central portion of the head case 19. The insertion space 20 is a space through which the flexible substrate 35 is inserted, and is formed in a state of penetrating the head case 19 in the plate thickness direction. Further, a liquid introduction path 21 through which the ink introduced from the ink cartridge 7 flows is formed inside the head case 19. The lower end of the liquid introduction path 21 is connected to the common liquid chamber 26 (specifically, the penetration portion 34) via the liquid introduction port 53. In the present embodiment, the liquid introduction paths 21 are formed on both sides in the direction orthogonal to the nozzle row direction with the insertion space 20 in between, corresponding to the two common liquid chambers 26. Further, as shown in FIG. 4, a position facing the upper end opening of the vertical flow paths 49 of the first branch flow paths 47a and 47b in the head case 19, that is, a direction orthogonal to the nozzle row direction from the region facing the common liquid chamber 26. Common flow paths 51a and 51b are formed at the positions deviated from the above. In short, the first piezoelectric element row side common flow path 51a communicating with the first piezoelectric element row side first branch flow path 47a and the second piezoelectric element row side common flow path communicating with the second piezoelectric element row side first branch flow path 47b. The road 51b is formed so as to penetrate in the plate thickness direction. As shown in FIG. 6 and the like, these common flow paths 51a and 51b are opened on the upper surface of the head case 19, respectively, and communicate with the atmosphere (specifically, the atmosphere inside the housing of the printer 1) (in other words, open to the atmosphere). ) Has been done. In the following, the opening 58a at the upper end of the common flow path 51a on the row side of the first piezoelectric element is referred to as the opening port 58a to the atmosphere on the row side of the first piezoelectric element, and the opening 58b at the upper end of the common flow path 51b on the row side of the second piezoelectric element is referred to as the second. It is referred to as a piezoelectric element row side atmosphere opening 58b. The first piezoelectric element row side atmosphere opening 58a and the second piezoelectric element row side atmosphere opening 58b correspond to the atmosphere opening in the present invention.

Then, as shown in FIG. 3 and the like, a case space 22 having a depth not to hinder the flexible deformation of the sealing film 39 is provided from the lower surface of the lower surface of the head case 19 corresponding to the common liquid chamber 26. It is formed in a dented state. The portion of the case space 22 facing the facing space 40 forms compliance spaces 56a and 56b together with the facing space 40. In the present embodiment, two compliance spaces 56a and 56b are formed corresponding to the two common liquid chambers 26. Specifically, it is sealed with the first piezoelectric element row side compliance space 56a, which is a kind of the second space in the present invention, separated from the common liquid chamber 26 communicating with the first nozzle row 44a by the sealing film 39. A second piezoelectric element row-side compliance space 56b, which is a kind of the second space in the present invention, is formed by the film 39, which is isolated from the common liquid chamber 26 communicating with the second nozzle row 44b. Here, the compliance spaces 56a and 56b are separated from the common liquid chamber 26 by the sealing film 39, but the sealing film 39 easily permeates the moisture from the common liquid chamber 26, so that the humidity tends to be high. .. In short, the compliance spaces 56a and 56b are more likely to allow moisture to enter from the common liquid chamber 26 than the piezoelectric element row accommodating spaces 46a and 46b partitioned by the rigid sealing plate 33 and the flow path substrate 29.

Further, the case space 22 in the present embodiment extends from the portion of the compliance spaces 56a and 56b facing the facing space 40 to the outside of the facing space 40 in the direction orthogonal to the nozzle row direction. That is, as shown in FIGS. 3 and 4, the width of the case space 22 (specifically, the dimension in the direction orthogonal to the nozzle row direction) is formed wider than the width of the common liquid chamber 26 (that is, the facing space 40). Has been done. The vertical flow paths 49 of the first branch flow paths 47a and 47b are communicated with each other through the communication port 54 at the end of the portion of the case space 22 extending outward from the facing space 40. Further, common flow paths 51a and 51b are communicated with each other on the upper surface of the case space 22 facing the communication port 54. In other words, the vertical flow paths 49 of the first branch flow paths 47a and 47b and the common flow paths 51a and 51b face each other vertically at the end of the portion extending outside the facing space 40 of the case space 22. It is communicated in a state. Then, the space from the portion where the vertical flow path 49 and the common flow paths 51a and 51b are communicated to the compliance spaces 56a and 56b forms the second branch flow paths 57a and 57b. That is, on the lower surface of the head case 19, the first piezoelectric element row side second branch flow path 57a communicating with the first piezoelectric element row side compliance space 56a and the second piezoelectric element communicating with the second piezoelectric element row side compliance space 56b The second branch flow path 57b on the element row side is formed. Since the second branch flow paths 57a and 57b have a larger flow path area and a shorter flow path length than the first branch flow paths 47a and 47b, the flow paths for gas are larger than those of the first branch flow paths 47a and 47b. The resistance is low (or low). In other words, the first branch flow paths 47a and 47b have higher (or larger) flow path resistance to gas than the second branch flow paths 57a and 57b.

As described above, the first piezoelectric element row side compliance space 56a is a series of flow paths including the first piezoelectric element row side second branch flow path 57a and the first piezoelectric element row side common flow path 51a (hereinafter, the first piezoelectric element). It is open to the atmosphere from the first piezoelectric element row-side atmosphere opening 58a through the row-side second atmosphere opening path 60a). Similarly, the second piezoelectric element row side compliance space 56b is a series of flow paths including the second piezoelectric element row side second branch flow path 57b and the second piezoelectric element row side common flow path 51b (hereinafter, the second piezoelectric element row). It is open to the atmosphere from the second piezoelectric element row side atmosphere opening 58b through the side second atmosphere opening path 60b). That is, the first piezoelectric element row-side second atmospheric open passage 60a and the second piezoelectric element row-side second atmospheric open passage 60b correspond to the second atmospheric open passage in the present invention. On the other hand, the first piezoelectric element row accommodating space 46a is a series of flow paths including the first piezoelectric element row side first branch flow path 47a and the first piezoelectric element row side common flow path 51a (hereinafter, the first piezoelectric element row side first). It is open to the atmosphere from the first piezoelectric element row-side atmosphere opening 58a) through the 1 atmosphere opening path 59a). Similarly, the second piezoelectric element row accommodating space 46b is a series of flow paths including the first piezoelectric element row side first branch flow path 47b and the second piezoelectric element row side common flow path 51b (hereinafter, the second piezoelectric element row side). It is open to the atmosphere from the second piezoelectric element row side atmosphere opening 58b through the first atmosphere opening path 59b). That is, the first air opening path 59a on the first piezoelectric element row side and the first atmospheric opening path 59b on the second piezoelectric element row side correspond to the first atmospheric opening path in the present invention.

Here, the first piezoelectric element row-side first atmosphere opening path 59a and the first piezoelectric element row-side second atmosphere opening path 60a are branched on the way from the first piezoelectric element row-side atmosphere opening 58a communicating with the atmosphere. Specifically, it is commonly formed up to the portion of the case space 22 where the first piezoelectric element row-side first branch flow path 47a and the first piezoelectric element row-side common flow path 51a communicate with each other), and the first piezoelectric element is formed from this branch. The first piezoelectric element row-side first branch flow path 47a, which is the flow path to the element row accommodation space 46a, is the first piezoelectric element row-side second flow path from the same branch to the first piezoelectric element row-side compliance space 56a. Since the flow path resistance is higher than that of the branch flow path 57a, the flow path resistance of the first piezoelectric element row-side first atmosphere open path 59a is higher than that of the first piezoelectric element row-side second atmosphere open path 60a. There is. Similarly, the second piezoelectric element row-side first atmosphere opening path 59b and the second piezoelectric element row-side second atmosphere opening path 60b are on the way from the second piezoelectric element row-side atmosphere opening 58b that communicates with the atmosphere. A branch (specifically, a portion of the case space 22 where the first piezoelectric element row-side first branch flow path 47b and the second piezoelectric element row-side common flow path 51b communicate with each other) is formed in common, and from this branch, the first 2 The first piezoelectric element row side first branch flow path 47b, which is the flow path to the piezoelectric element row accommodation space 46b, is the second piezoelectric element row side, which is the flow path from the same branch to the second piezoelectric element row side compliance space 56b. Since the flow path resistance is higher than that of the second branch flow path 57b, the second piezoelectric element row side first atmosphere open path 59b has a higher flow path resistance than the second piezoelectric element row side second atmosphere open path 60b. It has become.

As a result, it is possible to suppress the intrusion of moisture (or moisture) from the compliance spaces 56a and 56b into the piezoelectric element row accommodating spaces 46a and 46b. In addition, it is possible to suppress the intrusion of moisture (or moisture) into the piezoelectric element row accommodating spaces 46a and 46b from the inside of the housing of the printer 1, which tends to be in a humid environment. As a result, the adhesion of water to the piezoelectric element 32 can be suppressed, and eventually the destruction of the piezoelectric element 32 can be suppressed. Further, in the present embodiment, the first piezoelectric element row side first atmosphere opening path 59a and the first piezoelectric element row side second atmosphere opening path 60a are common from the first piezoelectric element row side atmosphere opening port 58a to the branch. Since it is formed, the configuration of the recording head 3 can be simplified as compared with the case where the first piezoelectric element row-side first atmosphere opening path and the first piezoelectric element row-side second atmosphere opening path are separately opened to the atmosphere. Further, as compared with the configuration in which the first air opening path on the row side of the first piezoelectric element and the second air opening path on the row side of the first piezoelectric element are separately opened to the atmosphere, a decrease in the strength of the head case 19 can be suppressed, and as a result, a decrease in strength can be suppressed. It is possible to suppress a decrease in the strength of the recording head 3. Further, since the first piezoelectric element row side first atmosphere opening path 59b and the second piezoelectric element row side second atmosphere opening path 60b are commonly formed from the second piezoelectric element row side atmosphere opening 58b to the branch, the second piezoelectric element row side first atmosphere opening path 59b and the second piezoelectric element row side second atmosphere opening path 60b are formed in common. 2 The configuration of the recording head 3 can be simplified as compared with the case where the first air opening path on the row side of the piezoelectric element and the second open path to the atmosphere on the row side of the second piezoelectric element are separately opened to the atmosphere. Further, as compared with the configuration in which the first air opening path on the second piezoelectric element row side and the second atmospheric opening path on the second piezoelectric element row side are separately opened to the atmosphere, a decrease in the strength of the head case 19 can be suppressed, and as a result, a decrease in strength can be suppressed. It is possible to suppress a decrease in the strength of the recording head 3.

By the way, when the first air opening path communicates above the piezoelectric element row accommodating space, there is a possibility that dew condensation generated in the first atmospheric open path drips and invades into the piezoelectric element row accommodating space. However, in the present embodiment, the first branch flow paths 47a and 47b of the first atmospheric open paths 59a and 59b are provided with the horizontal flow path 48 extending from the piezoelectric element row accommodating spaces 46a and 46b along the nozzle surface 25. Even if dew condensation occurs in the first open air passages 59a and 59b, it is possible to prevent the dew condensation from entering the piezoelectric element row accommodating spaces 46a and 46b. As a result, the adhesion of water to the piezoelectric element 32 can be further suppressed, and eventually the destruction of the piezoelectric element 32 can be further suppressed.

Then, the recording head 3 configured as described above introduces the ink from the ink cartridge 7 into the pressure chamber 30 via the liquid introduction path 21, the common liquid chamber 26, the individual communication passage 28, and the like. In this state, if the drive signal from the control unit is supplied to the piezoelectric element 32 via the flexible substrate 35 or the like, the piezoelectric element 32 is driven and the ink in the pressure chamber 30 fluctuates in pressure. By utilizing this pressure fluctuation, the recording head 3 ejects ink droplets from the nozzle 24. A series of flow paths including a liquid introduction path 21, a common liquid chamber 26, an individual communication passage 28, and a pressure chamber 30 correspond to the liquid flow path in the present invention.

By the way, in the above-described first embodiment, the horizontal flow path 48 is connected to the side surfaces of the piezoelectric element row accommodating spaces 46a and 46b, but the present invention is not limited to this. For example, in the second embodiment shown in FIG. 7, the horizontal flow path 48', which is a part of the first branch flow paths 47a'and 47b', is connected to the lower surface (that is, the bottom surface) of the piezoelectric element row accommodating spaces 46a and 46b. Has been done. Note that FIG. 7 is a cross-sectional view of the recording head 3 corresponding to the CC line cross section in the first embodiment.

Specifically, the horizontal flow path 48'in the present embodiment is formed in a groove shape on the upper surface of the flow path substrate 29 on which the diaphragm 31 is laminated. In short, the diaphragm 31 in the region corresponding to the horizontal flow path 48'is removed, and the flow path substrate 29 in the region is formed so as to be recessed from the upper surface. The groove in which the flow path substrate 29 is recessed extends from a position where it overlaps with the vertical flow path 49 ′ penetrating the sealing plate 33 to a position where it overlaps with the piezoelectric element row accommodating spaces 46a and 46b, respectively. Then, the horizontal flow path 48'is formed by sealing the open side of the groove in which the flow path substrate 29 is recessed with the sealing plate 33. That is, the horizontal flow path 48'in the present embodiment is formed in a state where the open side of the groove of the flow path substrate 29 is sealed with the sealing plate 33. As shown in FIG. 7, the end of the horizontal flow path 48'on the side opposite to the vertical flow path 49'is located below the piezoelectric element row accommodation spaces 46a and 46b, and the piezoelectric element row accommodation space is located at that position. It is connected to the bottom surfaces of 46a and 46b. As a result, even if dew condensation occurs in the first open air passages 59a'and 59b', it is possible to further prevent the dew condensation from dripping and entering the piezoelectric element row accommodating spaces 46a and 46b. Since the other configurations are the same as those in the first embodiment described above, the description thereof will be omitted. Further, in the present embodiment, the horizontal flow path 48'is formed at the interface between the flow path substrate 29 and the sealing plate 33, but the present invention is not limited to this, and at least a part of the first branch flow path is a piezoelectric element. It suffices if it is formed below the row accommodation space (that is, between the piezoelectric element row accommodation space and the nozzle surface).

Further, in the first embodiment and the second embodiment described above, the first piezoelectric element row accommodating space 46a and the first piezoelectric element row side compliance space 56a pass through the first piezoelectric element row side air opening 58a common to both. It was opened to the atmosphere, and the second piezoelectric element row accommodation space 46b and the second piezoelectric element row side compliance space 56b were opened to the atmosphere through the second piezoelectric element row side atmosphere opening 58b common to both. Not limited. For example, in the third embodiment shown in FIGS. 8 to 11, the first piezoelectric element row accommodating space 46a and the second piezoelectric element row accommodating space 46b are opened to the atmosphere through the accommodating space atmosphere opening 73 common to both. The first piezoelectric element row-side compliance space 56a and the second piezoelectric element row-side compliance space 56b are open to the atmosphere through the compliance space air opening 77 common to both.

Hereinafter, the third embodiment will be described in detail. FIG. 8 is a plan view of the compliance board 37 of the recording head 3 according to the third embodiment as viewed from above. 9 is a schematic representation of a DD line cross section, FIG. 10 is a schematic representation of an EE line cross section, and FIG. 11 is a schematic representation of an FF line cross section. As shown in FIGS. 8 to 11, also in the present embodiment, as in the first embodiment described above, a first nozzle row composed of a plurality of nozzles 24 arranged side by side on one side (right side in FIG. 9 and the like). A second nozzle row 44b composed of a plurality of nozzles 24 arranged side by side on the other side (left side in FIG. 9 and the like) is formed with 44a. Further, also in the present embodiment, a series of flow paths including the liquid introduction path 21 communicating with the first nozzle row 44a, the common liquid chamber 26, the individual communication passage 28, and the pressure chamber 30 (hereinafter referred to as the first liquid flow path 68a). A series of flow paths (hereinafter referred to as the second liquid flow path 68b) including a liquid introduction path 21, a common liquid chamber 26, an individual communication passage 28, and a pressure chamber 30 communicating with the second nozzle row 44b. It is formed in the recording head 3. Further, also in the present embodiment, the first piezoelectric element row accommodating space 46a (corresponding to the first space for the first drive element group in the present invention) accommodating the first piezoelectric element row 45a and the second piezoelectric element row 45b are provided. A second piezoelectric element row accommodating space 46b (corresponding to the first space for the second driving element group in the present invention) to be accommodated is formed.

On the other hand, unlike the first embodiment described above, the case space 22'recessed from the lower surface of the head case 19 is formed only in the region where the lower surface faces the facing space 40 partitioned by the sealing film 39. The case space 22'forms compliance spaces 56a and 56b together with the facing space 40. In the present embodiment, the first piezoelectric element row side compliance space 56a (this) is in contact with the first liquid flow path 68a with the sealing film 39 sandwiched between them, and moisture is more likely to enter than the first piezoelectric element row accommodating space 46a. The second space is in contact with the second liquid flow path 68b with the sealing film 39 sandwiched between the first liquid flow path side (corresponding to the second space on the first liquid flow path side) in the present invention, and moisture is more likely to enter than the second piezoelectric element row accommodating space 46b. A piezoelectric element row-side compliance space 56b (corresponding to the second liquid flow path-side second space in the present invention) is formed. One end (right side in FIG. 8) of the first piezoelectric element row side compliance space 56a and the second piezoelectric element row side compliance space 56b in the nozzle row direction is along the nozzle surface 25 (horizontal plane in this embodiment). The extending horizontal flow path 75 for the compliance space is connected. That is, the first piezoelectric element row side compliance space 56a and the second piezoelectric element row side compliance space 56b are communicated with each other via the compliance space horizontal flow path 75.

As shown in FIG. 9, the horizontal flow path 75 for the compliance space in the present embodiment is formed on the compliance board 37 and communicates with the facing space 40 of the compliance spaces 56a and 56b. Further, as shown in FIG. 8, the horizontal flow path 75 for the compliance space extends from the communication position with the first piezoelectric element row side compliance space 56a to the outside of the second piezoelectric element row side compliance space 56b in the nozzle row direction. It is routed and branched into a portion communicating with the second piezoelectric element row side compliance space 56b and a portion communicating with the compliance space vertical flow path 76 outside the second piezoelectric element row side compliance space 56b. There is. Then, one of the branches is connected to the second piezoelectric element row side compliance space 56b, and the other is compliant at a position deviated from the second piezoelectric element row side compliance space 56b to the other side in the direction orthogonal to the nozzle row direction. It communicates with the vertical flow path 76 for space. The compliance space vertical flow path 76 is a flow path formed so as to penetrate the head case 19 in the plate thickness direction, and the upper end thereof is opened on the upper surface of the head case 19. In the following, the opening 77 at the upper end of the vertical flow path 76 for the compliance space will be referred to as the air opening 77 for the compliance space. The horizontal flow path for the compliance space may be formed on the lower surface of the head case. Alternatively, it may be formed on both the compliance board and the head case.

As described above, the compliance space 56a on the row side of the first piezoelectric element is a series of flow paths including the horizontal flow path 75 for the compliance space and the vertical flow path 76 for the compliance space (hereinafter, the second open path to the atmosphere on the row side of the first piezoelectric element). It is open to the atmosphere through the compliance space air opening 77 (referred to as 78a). Further, the compliance space 56b on the second piezoelectric element row side is similarly a series of flow paths including the horizontal flow path 75 for the compliance space and the vertical flow path 76 for the compliance space (hereinafter, the second open path to the atmosphere on the second piezoelectric element row side). It is open to the atmosphere through the compliance space air opening 77 (referred to as 78b). That is, the second air opening path 78a on the row side of the first piezoelectric element and the second air opening path 78b on the row side of the second piezoelectric element are common from the air opening 77 for the compliance space to the branch of the horizontal flow path 75 for the compliance space. It is formed and communicated with the atmosphere through the air opening 77 for the compliance space. The first piezoelectric element row side second atmosphere open path 78a corresponds to the first liquid flow path side second atmosphere open path in the present invention, and the second piezoelectric element row side second atmosphere open path 78b is the second atmosphere open path 78b in the present invention. It corresponds to the second open air path on the liquid flow path side.

Further, as shown in FIGS. 8 and 11, in the present embodiment, the horizontal flow path 70 for the accommodating space is connected to the piezoelectric element row accommodating spaces 46a and 46b. Specifically, on the other end (left side in FIG. 8) in the nozzle row direction of the first piezoelectric element row accommodating space 46a and the second piezoelectric element row accommodating space 46b, on the nozzle surface 25 (horizontal plane in the present embodiment). A horizontal flow path 70 for a storage space extending along the line is connected. That is, the first piezoelectric element row accommodating space 46a and the second piezoelectric element row accommodating space 46b are communicated with each other via the accommodation space horizontal flow path 70. As shown in FIG. 11, the accommodation space horizontal flow path 70 in the present embodiment is a flow path on the open side of the groove formed on the lower surface of the sealing plate 33, similarly to the horizontal flow path 48 in the first embodiment. It is formed in a state of being sealed with the substrate 29. Further, as shown in FIG. 8, the horizontal flow path 70 for the accommodation space in the present embodiment is outward from the communication position with the second piezoelectric element row accommodation space 46b in the nozzle row direction of the first piezoelectric element row accommodation space 46a. It is routed up to, and is branched into a portion communicating with the first piezoelectric element row accommodating space 46a and a portion communicating with the accommodating space vertical flow path 71 outside the first piezoelectric element row accommodating space 46a. .. Then, one of the branches is connected to the first piezoelectric element row accommodating space 46a, and the other is for the accommodating space at a position deviated to one side in the direction orthogonal to the nozzle row direction from the first piezoelectric element row accommodating space 46a. It communicates with the vertical flow path 71.

As shown in FIG. 10, the accommodation space vertical flow path 71 is formed in a state of penetrating the sealing plate 33 in the thickness direction, similarly to the vertical flow path 49 in the first embodiment. The upper end of the vertical flow path 71 for the accommodation space is communicated with the case-side vertical flow path 72 formed in the head case 19 via the conduction port 54'opened in the compliance substrate 37. The case-side vertical flow path 72 is a flow path formed in a state of penetrating the head case 19 in the plate thickness direction, similarly to the compliance space vertical flow path 76. The upper end of the case-side vertical flow path 72 is opened on the upper surface of the head case 19. Hereinafter, the opening 73 at the upper end of the case-side vertical flow path 72 will be referred to as an air opening 73 for the accommodation space. As shown in FIG. 8, the position of the horizontal flow path 75 for the compliance space communicating with the vertical flow path 76 for the compliance space and the conduction port 54 ′ communicating with the vertical flow path 72 on the case side are located on the upper surface of the compliance substrate 37. Since they are arranged diagonally, the accommodation space opening port 73 and the compliance space opening port 77 are formed diagonally on the upper surface of the recording head 3. That is, the accommodation space air opening 73 is formed at the other end of the upper surface of the head case 19 in the nozzle row direction and on one side in the direction orthogonal to the nozzle row direction, and is formed for the compliance space. The atmosphere opening 77 is formed at one end of the upper surface of the head case 19 in the nozzle row direction and at the other end in the direction orthogonal to the nozzle row direction. In short, the air opening 73 for the accommodation space and the air opening 77 for the compliance space are formed so as to be separated from each other in the nozzle row direction and in the direction orthogonal to the nozzle row direction.

As described above, the first piezoelectric element row accommodating space 46a is a series of flow paths including the accommodating space horizontal flow path 70, the accommodating space vertical flow path 71, and the case-side vertical flow path 72 (hereinafter, the first piezoelectric element array). It is open to the atmosphere from the air opening 73 for the accommodation space through the side first air opening path 74a). Further, the second piezoelectric element row accommodating space 46b is similarly a series of flow paths including a horizontal flow path 70 for the accommodating space, a vertical flow path 71 for the accommodating space, and a case-side vertical flow path 72 (hereinafter, the second piezoelectric element array). It is open to the atmosphere from the air opening 73 for the accommodation space through the side first air opening path 74b). That is, the first atmospheric opening path 74a on the first piezoelectric element row side and the first atmospheric opening path 74b on the second piezoelectric element row side are common from the atmospheric opening 73 for the accommodation space to the branch of the horizontal flow path 70 for the accommodation space. It is formed and communicated with the atmosphere through the air opening 73 for the accommodation space. The first piezoelectric element row side first atmosphere open path 74a corresponds to the first drive element group side first atmosphere open path in the present invention, and the second piezoelectric element row side first atmosphere open path 74b is the first atmosphere open path 74b in the present invention. 2 Corresponds to the first open path to the atmosphere on the drive element group side. Further, the portion of the horizontal flow path 70 for the accommodation space from the branch to the first piezoelectric element row accommodation space 46a corresponds to the partial flow path on the side of the first drive element group, and from the branch of the horizontal flow path 70 for the accommodation space. The portion up to the second piezoelectric element row accommodating space 46b corresponds to the second drive element group side partial flow path.

Here, the first piezoelectric element row side first atmosphere opening path 74a and the second piezoelectric element row side first atmosphere opening path 74b are the first piezoelectric element row side second atmosphere opening path 78a and the second piezoelectric element row side first atmosphere opening path 74b. 2 It is formed so that the flow path resistance is higher than that of the open air passage 78b. For example, a part or all of the first piezoelectric element row side first atmosphere open path 74a and the second piezoelectric element row side first atmosphere open path 74b are the first piezoelectric element row side second atmosphere open path 78a and the second piezoelectric element. It is formed so that the flow path area is smaller than that of the second open air passage 78b on the element row side. Alternatively, the first piezoelectric element row side first atmosphere opening path 74a and the second piezoelectric element row side first atmosphere opening path 74b are the first piezoelectric element row side second atmosphere opening path 78a and the second piezoelectric element row side second atmosphere opening path 74a. It is formed so that the length of the flow path is longer than that of the open air passage 78b. As a result, moisture (or moisture) on the outside of the recording head 3 (specifically, inside the housing of the printer 1) is passed through the first piezoelectric element row-side first atmosphere open path 74a or the second piezoelectric element row-side first atmosphere open path 74b. ) Can be prevented from entering the first piezoelectric element row accommodating space 46a or the second piezoelectric element row accommodating space 46b. As a result, the adhesion of water to the piezoelectric element 32 can be suppressed, and eventually the destruction of the piezoelectric element 32 can be suppressed.

According to the present embodiment, the first piezoelectric element row accommodating space 46a and the second piezoelectric element row accommodating space 46b, and the first piezoelectric element row side compliance space 56a and the second piezoelectric element row side compliance space 56b are Moisture from the first piezoelectric element row side compliance space 56a and the second piezoelectric element row side compliance space 56b to the first piezoelectric element row accommodation space 46a and the second piezoelectric element row accommodation space 46b because they are not communicated in the recording head 3. The invasion of (or moisture) can be suppressed. As a result, the adhesion of water to the piezoelectric element 32 can be further suppressed, and eventually the destruction of the piezoelectric element 32 can be further suppressed. Further, the first piezoelectric element row side first atmosphere open path, the second piezoelectric element row side first atmosphere open path, the first piezoelectric element row side second atmosphere open path, and the second piezoelectric element row side second atmosphere open path. The decrease in the strength of the recording head 3 can be suppressed as compared with the configuration in which the roads are separately opened to the atmosphere. Further, since the air opening 73 for the accommodation space and the air opening 77 for the compliance space are formed so as to be separated from each other in the nozzle row direction, it is possible to suppress a decrease in the strength of the recording head 3. That is, the first atmospheric opening passages 74a and 74b and the second atmospheric opening passages 78a and 78b are separated from each other as compared with the case where the air opening for the accommodation space and the atmospheric opening for the compliance space are provided close to each other. Therefore, it is possible to suppress a local decrease in the strength of the recording head 3. In addition, from the first piezoelectric element row side compliance space 56a and the second piezoelectric element row side compliance space 56b, the first piezoelectric element row accommodation space 46a is passed through the compliance space air opening 77 and the accommodation space air opening 73. In addition, it is possible to prevent moisture from entering the second piezoelectric element row accommodating space 46b. Further, in the present embodiment, the air opening 73 for the accommodation space and the air opening 77 for the compliance space are formed so as to be separated from each other in the direction orthogonal to the nozzle row direction, so that the first piezoelectric element row side compliance space is formed. Moisture from the 56a and the second piezoelectric element row side compliance space 56b to the first piezoelectric element row accommodation space 46a and the second piezoelectric element row accommodation space 46b via the compliance space atmosphere opening 77 and the accommodation space atmosphere opening 73. Can be further suppressed from invading.

Further, in the present embodiment, since the first open air passages 74a and 74b include the horizontal flow path 70 for the accommodation space extending along the nozzle surface 25, dew condensation occurs in the first open air passages 74a and 74b. Even if this occurs, it is possible to prevent the dew condensation from entering the piezoelectric element row accommodating spaces 46a and 46b. That is, since the first atmospheric open paths 74a and 74b are connected to the side surfaces of the piezoelectric element row accommodating spaces 46a and 46b, dew condensation hangs down in the first atmospheric open paths 74a and 74b and the piezoelectric element row accommodating spaces 46a and 46b. It does not invade inside. As a result, the adhesion of water to the piezoelectric element 32 can be further suppressed, and eventually the destruction of the piezoelectric element 32 can be further suppressed. The horizontal flow path 70 for the accommodation space may be formed in a groove shape on the upper surface of the flow path substrate on which the diaphragms are laminated, as in the horizontal flow path 48'of the second embodiment shown in FIG. That is, a configuration is adopted in which the horizontal flow path for the accommodation space is formed in a state where the open side of the groove of the flow path substrate is sealed with a sealing plate, and the end portion thereof is connected to the bottom surface of the piezoelectric element row accommodation space. You can also. In this way, even if dew condensation occurs in the first air opening path on the first piezoelectric element row side and in the first atmospheric open path on the second piezoelectric element row side, the dew condensation is in the first piezoelectric element row accommodating space. And it is possible to further suppress the invasion into the second piezoelectric element row accommodating space. In short, at least a part of the first air opening path on the first piezoelectric element row side is formed below the first piezoelectric element row accommodation space (that is, between the first piezoelectric element row accommodation space and the nozzle surface). At least a part of the first air open path on the second piezoelectric element row side may be formed below the second piezoelectric element row accommodation space (that is, between the second piezoelectric element row accommodation space and the nozzle surface). desirable. Since the other configurations are the same as those in the first embodiment described above, the description thereof will be omitted.

Further, in the third embodiment described above, in the plan view of the recording head 3, the accommodation space air opening 73 and the compliance space air opening 77 are arranged at diagonal positions, but this is limited to this. I can't. For example, in the fourth embodiment shown in FIG. 12, in the plan view of the recording head 3, the air opening 73'for the accommodation space and the air opening 77' for the compliance space are substantially centered in the direction orthogonal to the nozzle row direction. Is formed so as to be separated in the nozzle row direction.

Specifically, as shown in FIG. 12, the horizontal flow path 75'for the compliance space in the present embodiment is the first from the center of the compliance board 37 in the direction orthogonal to the nozzle row direction in the plan view of the compliance board 37. 1 The flow path to the piezoelectric element row side compliance space 56a and the flow path from the center of the compliance substrate 37 in the direction orthogonal to the nozzle row direction to the second piezoelectric element row side compliance space 56b are orthogonal to the nozzle row direction. It is formed symmetrically in the direction. The connection point with the vertical flow path 76'for the compliance space is between the first piezoelectric element row side compliance space 56a and the second piezoelectric element row side compliance space 56b (in this embodiment, it is orthogonal to the nozzle row direction). It is formed in the substantially center of the compliance substrate 37 in the direction). Therefore, the compliance space air opening 77', which is the upper end of the compliance space vertical flow path 76', is one end of the upper surface of the head case 19 in the nozzle row direction and is orthogonal to the nozzle row direction. It is formed approximately in the center of the direction. As a result, the length of the flow path from the vertical flow path 76'for the compliance space to the compliance space 56a on the row side of the first piezoelectric element and the flow from the vertical flow path 76'for the compliance space to the compliance space 56b on the row side of the second piezoelectric element. The length of the road can be made uniform. As a result, the humidity in the first piezoelectric element row-side compliance space 56a and the humidity in the second piezoelectric element row-side compliance space 56b can be made uniform.

Further, the accommodation space horizontal flow path 70'in the present embodiment is the center of the compliance substrate 37 in the direction orthogonal to the nozzle row direction at the end opposite to the compliance space horizontal flow path 75'in the nozzle row direction. The flow path from the center to the first piezoelectric element row accommodation space 46a and the flow path from the center of the compliance substrate 37 in the direction orthogonal to the nozzle row direction to the second piezoelectric element row accommodation space 46b are orthogonal to the nozzle row direction. It is formed symmetrically in the direction. The connection point with the vertical flow path 71'for the accommodation space is between the first piezoelectric element row accommodation space 46a and the second piezoelectric element row accommodation space 46b (in the present embodiment, in the direction orthogonal to the nozzle row direction). It is formed at a position corresponding to substantially the center of the compliance board 37). Therefore, the accommodation space vertical flow path 71'and the accommodation space atmosphere opening 73'connected via the conduction port 54'are the other end of the upper surface of the head case 19 in the nozzle row direction. , Formed approximately in the center in the direction orthogonal to the nozzle row direction. As a result, the length of the flow path from the vertical flow path 71'for the accommodation space to the accommodation space 46a of the first piezoelectric element row (that is, corresponding to the partial flow path on the side of the second drive element group) and the vertical flow path 71 for the accommodation space The length of the flow path from ′ to the second piezoelectric element row accommodating space 46b can be made uniform. As a result, the humidity in the first piezoelectric element row accommodating space 46a and the humidity in the second piezoelectric element row accommodating space 46b can be made uniform. Further, also in the present embodiment, since the air opening 73'for the accommodation space and the air opening 77' for the compliance space are formed so as to be separated from each other in the nozzle row direction, it is possible to suppress a decrease in the strength of the recording head 3. Further, from the first piezoelectric element row side compliance space 56a and the second piezoelectric element row side compliance space 56b, the first piezoelectric element row accommodation space is passed through the compliance space atmosphere opening 66'and the accommodation space atmosphere opening 73'. It is possible to prevent moisture from entering the 46a and the second piezoelectric element row accommodating space 46b. Since the other configurations are the same as those in the third embodiment described above, the description thereof will be omitted.

Further, unlike the first to fourth embodiments described above, the first piezoelectric element row accommodating space 46a, the second piezoelectric element row accommodating space 46b, the first piezoelectric element row side compliance space 56a, and the second piezoelectric element row The side compliance spaces 56b can also be opened to the atmosphere from individual air opening ports. For example, in the fifth embodiment shown in FIGS. 13 to 15, the first piezoelectric element row accommodating space 46a is provided from the first piezoelectric element row accommodating space atmosphere opening 80a, and the second piezoelectric element row accommodating space 46b is second. From the piezoelectric element row accommodation space atmosphere opening 80b, the first piezoelectric element row side compliance space 56a is from the first piezoelectric element row side compliance space atmosphere opening 81a, and the second piezoelectric element row side compliance space 56b is the second piezoelectric. Each of them is open to the atmosphere from the air opening 81b for the compliance space on the element train side. Note that FIG. 13 is a plan view of the compliance substrate 37 of the recording head 3 according to the fifth embodiment as viewed from above. Further, FIG. 14 is a diagram schematically showing a cross section taken along the line GG, and FIG. 15 is a diagram schematically showing a cross section taken along the line HG.

In the present embodiment, the compliance space atmosphere opening ports 81a and 81b are opened at one end in the nozzle row direction, and the accommodation space atmosphere opening ports 80a and 80b are opened at the other end in the nozzle row direction. Has been done. As shown in FIGS. 13 and 15, the first piezoelectric element row accommodating space air opening path 82a (the present invention) communicating the first piezoelectric element row accommodating space 46a and the first piezoelectric element row accommodating space air opening port 80a. (A type of first air opening path) and the second piezoelectric element row accommodating space atmospheric opening path 82b (2) that communicates the second piezoelectric element row accommodating space 46b and the second piezoelectric element row accommodating space atmospheric opening port 80b ( The first open air path) in the present invention includes a horizontal flow path 48 ″, a vertical flow path 49 ″, and a case flow path 84 for a storage space, respectively. Similar to the horizontal flow path 48 of the first embodiment, the horizontal flow path 48 ″ is formed on the nozzle surface 25 from the other end of the piezoelectric element row accommodation space 46a in the nozzle row direction to a position communicating with the vertical flow path 49 ″. It is a flow path extending along the flow path. Further, the vertical flow path 49 ″ penetrates the sealing plate 33 outside the piezoelectric element row accommodation space 46a in the direction orthogonal to the nozzle row direction, as in the vertical flow path 49 of the first embodiment. The vertical flow path 49 ″ communicates with the accommodation space case flow path 84 via the communication port 54 ″. The accommodation space case flow path 84 is formed by two piezoelectric element trains. Two are formed so as to correspond to the accommodating spaces 46a and 46b in a direction orthogonal to the nozzle row direction, and the opening at the upper end of the accommodating space case flow path 84 is an air opening port 80a for the accommodating space. , 80b.

Further, as shown in FIGS. 13 and 14, the first compliance space open passage 83a (second in the present invention) communicating the first compliance element row side compliance space 56a and the first compliance space air opening 81a. (A type of open air path) and the open air path 83b for the second compliance space (the second open path to the atmosphere in the present invention) that communicates the compliance space 56b on the row side of the second piezoelectric element and the open air opening 81b for the second compliance space. The case space 22 "in the present embodiment is composed of a case space 22" and a case flow path 85 for the compliance space, respectively. As shown in FIG. 14, the case space 22 "in the present embodiment is formed at one end in the nozzle row direction. It extends from the portion of the compliance spaces 56a and 56b facing the facing space 40 to the region communicating with the compliance space case flow path 85. Then, the compliance space case flow path 85 is communicated with the end of the portion of the case space 22 ″ extending outward from the facing space 40. There are two compliance space case flow paths 85. Two are formed so as to correspond to the compliance spaces 56a and 56b in the direction orthogonal to the nozzle row direction, and the opening at the upper end of the case flow path 85 for the accommodation space is the open air opening 81a for the compliance space. , 81b.

Further, also in the present embodiment, the first piezoelectric element row accommodating space air opening path 82a and the second piezoelectric element row accommodating space atmospheric opening path 82b are for the first compliance space atmospheric opening path 83a and the second compliance space. It is formed so that the flow path resistance is higher than that of the open air passage 83b. For example, a part or all of the first piezoelectric element row accommodating space air opening path 82a and the second piezoelectric element row accommodating space atmospheric opening path 82b are the first compliance space atmospheric opening path 83a and the second compliance space atmospheric opening. It is formed so that the flow path area is smaller than that of the open path 83b. Alternatively, the first piezoelectric element row accommodating space air opening path 82a and the second piezoelectric element row accommodating space atmospheric opening path 82b are more than the first compliance space atmospheric opening path 83a and the second compliance space atmospheric opening path 83b. It is formed so that the length of the flow path becomes long. As a result, moisture (or moisture) inside the housing of the printer 1 outside the recording head 3 is released through the first piezoelectric element row accommodating space air opening path 82a and the second piezoelectric element row accommodating space atmospheric opening path 82b. It is possible to suppress the invasion into the first piezoelectric element row accommodating space 46a or the second piezoelectric element row accommodating space 46b. As a result, the adhesion of water to the piezoelectric element 32 can be suppressed, and eventually the destruction of the piezoelectric element 32 can be suppressed. Further, also in the present embodiment, since the air opening ports 80a and 80b for the accommodation space and the air opening ports 81a and 81b for the compliance space are formed so as to be separated from each other in the nozzle row direction, the decrease in the strength of the recording head 3 is suppressed. it can. Further, it is possible to prevent moisture from entering the piezoelectric element row accommodation spaces 46a and 46b from the compliance spaces 56a and 56b through the compliance space atmosphere openings 81a and 81b and the accommodation space atmosphere openings 80a and 80b. Since the other configurations are the same as those in the third embodiment described above, the description thereof will be omitted.

By the way, in each of the above-described embodiments, the printer 1 in which only one recording head 3 is mounted on the carriage 4 is illustrated, but the present invention is not limited to this. The present invention can also be applied to a recording head unit composed of a plurality of recording heads mounted on a carriage, or a recording head unit (so-called line head) in which a plurality of recording heads are arranged in the width direction of a recording medium.

As the sixth to eighth embodiments, a recording head unit 87 (corresponding to the liquid injection head unit in the present invention) including a plurality of recording heads 3 will be described as an example. FIG. 16 is a schematic view of the recording head unit 87 in the sixth embodiment as viewed from above (the side opposite to the nozzle surface 25). The recording head unit 87 in the present embodiment has a fixed plate or a fixed plate in which a plurality of (four in the present embodiment) recording heads 3 exemplified in the third embodiment are arranged along a direction orthogonal to the nozzle row direction. It is fixed to a fixing member 88 such as a holder. As described in the third embodiment, the air opening 73 for the accommodation space and the air opening 77 for the compliance space are opened on the upper surface of each recording head 3 at diagonal positions on the upper surface. Then, in each recording head 3, the air opening port 73 for the accommodation space is on one side (upper side in FIG. 16) in the direction orthogonal to the parallel direction of the recording heads 3, and the air opening port 77 for the compliance space is on the recording head 3. They are arranged side by side so as to be arranged on the other side (lower side in FIG. 16) in the direction orthogonal to the parallel arrangement direction. Therefore, the distance between the accommodation space opening port 73 of one recording head 3 and the accommodation space atmosphere opening 73 of the other recording head 3 in the adjacent recording heads 3 is for the accommodation space in the same recording head 3. It is narrower than the distance between the air opening 73 and the air opening 77 for the compliance space. Further, the distance between the compliance space air opening 77 of one recording head 3 and the compliance space air opening 77 of the other recording head 3 in the adjacent recording heads 3 is also the same as the accommodation space air in the same recording head 3. The distance between the opening 73 and the atmosphere opening 77 for the compliance space is narrower. As a result, it is possible to prevent moisture from entering the piezoelectric element row accommodation spaces 46a and 46b from the compliance spaces 56a and 56b through the compliance space air opening 77 and the accommodation space air opening 73.

Further, FIG. 17 is a schematic view of the recording head unit 87'in the seventh embodiment as viewed from above. The recording head unit 87'in the present embodiment is fixed to the fixing member 88'in a state where a plurality of recording heads 3 exemplified in the third embodiment (three in the present embodiment) are arranged along the nozzle row direction. Has been done. Further, also in the present embodiment, the distance between the compliance space air opening 77 of one recording head 3 and the compliance space air opening 77 of the other recording head 3 in the adjacent recording heads 3 is the same recording head 3. It is arranged so as to be narrower than the distance between the air opening 73 for the accommodation space and the air opening 77 for the compliance space. Specifically, the even-numbered recording heads 3 counted from one end of the recording heads 3 in the parallel direction are attached to the fixing member 88'by rotating half a turn with respect to the odd-numbered recording heads 3. .. As a result, also in the present embodiment, it is possible to prevent moisture from entering the piezoelectric element row accommodation spaces 46a and 46b from the compliance spaces 56a and 56b through the compliance space air opening 77 and the accommodation space air opening 73. it can.

Further, FIG. 18 is a schematic view of the recording head unit 87 ″ in the eighth embodiment as viewed from above. The recording head unit 87 ″ in the present embodiment has the recording head 3 exemplified in the fourth embodiment. A plurality of (three in the present embodiment) are arranged and fixed to the fixing member 88 ″ along the nozzle row direction. Therefore, in the present embodiment, the air opening 73 ′ for the accommodation space and the compliance space are fixed. The air opening 77'is aligned substantially in the center in the direction orthogonal to the parallel direction of the recording heads 3, and also in the present embodiment, one of the recording heads 3 in the adjacent recording heads 3 is aligned. The distance between the compliance space air opening 77'and the compliance space air opening 77'of the other recording head 3 is the same as the accommodation space air opening 73'and the compliance space air opening 73'in the same recording head 3. The recording heads 3 are arranged so as to be narrower than the distance from 77'. Specifically, the even-order recording heads 3 counted from one end of the recording heads 3 in the parallel direction are the odd-th recording heads. It is attached to the fixing member 88 ″ by rotating it half a turn with respect to 3. As a result, also in the present embodiment, moisture penetrates from the compliance spaces 56a and 56b into the piezoelectric element row accommodation spaces 46a and 46b through the compliance space air opening 77'and the accommodation space air opening 73'. Can be suppressed. The number of recording heads 3 provided in the recording head unit 87 in the sixth to eighth embodiments is not limited to the examples. In short, the recording head unit 87 may include two or more recording heads 3.

In the above, the so-called bending vibration type piezoelectric element 32 has been exemplified as the driving element, but the present invention is not limited to this, and for example, the so-called longitudinal vibration type piezoelectric element, the heat generating element, and the pressure using electrostatic force are used. Various actuators such as an electrostatic actuator that fluctuates the volume of the chamber can be adopted. Further, the open path to the atmosphere that opens the compliance space and the piezoelectric element row accommodating space illustrated in each embodiment to the atmosphere is not limited to the illustrated shape (cross-sectional shape, path, etc.), and can be set to any shape. Further, in the above, the nozzle rows 44a and 44b and the piezoelectric element rows 45a and 45b are formed linearly, but the present invention is not limited to this. For example, the present invention can be applied to a recording head having a nozzle group in which a plurality of nozzles are gathered and a piezoelectric element group in which a plurality of piezoelectric elements are gathered. Further, the vertical flow path 49, the vertical flow path 71 for the accommodation space, the vertical flow path 72 on the case side, the vertical flow path 76 for the compliance space, and the like are formed perpendicular to the horizontal plane, but this is limited to this. I can't. In short, it suffices if it is formed in a direction intersecting the horizontal plane. Further, the horizontal flow path 48, the horizontal flow path 70 for the accommodation space, the horizontal flow path 75 for the compliance space, and the like described above are formed along the horizontal plane, but the present invention is not limited thereto. For example, they may be tilted with respect to the horizontal plane.

In the above description, the inkjet recording head 3 which is a kind of liquid injection head and the recording head units 87, 87 ′, 87 ″ which are a kind of liquid injection head unit have been described as examples. Can also be applied to other liquid injection heads and liquid injection units. For example, a color material injection head used for manufacturing a color filter such as a liquid crystal display, an organic EL (Electro Luminescence) display, and a FED (surface). The present invention is also applied to an electrode material injection head used for forming an electrode such as a light emitting display), a bioorganic substance injection head used for manufacturing a biochip (biochemical element), and various injection units in which these are unitized. In the color material injection head for the display manufacturing apparatus or the injection unit provided with the color material injection head, a solution of each color material of R (Red), G (Green), and B (Blue) is injected as a kind of liquid. In the electrode material injection head for the electrode forming apparatus or the injection unit equipped with the electrode material injection head, a liquid electrode material is injected as a kind of liquid, and in the bioorganic material injection head for the chip manufacturing apparatus or the injection unit equipped with the liquid, a kind of liquid. A solution of bioorganic material is sprayed as.

1 ... printer, 2 ... recording medium, 3 ... recording head, 4 ... carriage, 5 ... carriage movement mechanism, 6 ... transfer mechanism, 7 ... ink cartridge, 8 ... timing belt, 9 ... pulse motor, 10 ... guide rod, 19 ... Head case, 20 ... Insertion space, 21 ... Liquid introduction path, 22 ... Case space, 23 ... Nozzle plate, 24 ... Nozzle, 25 ... Nozzle surface, 26 ... Common liquid chamber, 27 ... Communication section, 28 ... Supply path, 29 ... Communication board, 30 ... Pressure chamber, 31 ... Vibration plate, 32 ... Piezoelectric element, 33 ... Sealing board, 34 ... Penetration part, 35 ... Flexible board, 36 ... Connection space, 37 ... Compliance board, 38 ... Fixed board , 39 ... Sealing film, 40 ... Opposing space, 44a ... First nozzle row, 44b ... Second nozzle row, 45a ... First piezoelectric element row, 45b ... Second piezoelectric element row, 46a ... First piezoelectric element row Space, 46b ... Second piezoelectric element row accommodation space, 47a ... First piezoelectric element row side first branch flow path, 47b ... Second piezoelectric element row side first branch flow path, 48 ... Horizontal flow path, 49 ... Vertical flow path, 51a ... Common flow path on the row side of the first piezoelectric element, 51b ... Common flow path on the row side of the second piezoelectric element, 53 ... Liquid inlet, 54 ... Communication port, 56a ... Compliance space on the row side of the first piezoelectric element, 56b ... Second Piezoelectric element row side compliance space, 57a ... 1st piezoelectric element row side 2nd branch flow path, 57b ... 2nd piezoelectric element row side 2nd branch flow path, 58a ... 1st piezoelectric element row side atmosphere opening port, 58b ... 2nd piezoelectric element Element row side atmosphere opening port, 59a, 74a ... 1st piezoelectric element row side first atmosphere opening path, 59b, 74b ... Second piezoelectric element row side first atmosphere opening path, 60a, 78a ... First piezoelectric element row side first 2 Open air passages, 60b, 78b ... Second piezoelectric element row side second open air passage, 68a ... First liquid flow path, 68b ... Second liquid flow path, 70 ... Horizontal flow path for accommodation space, 71 ... Storage space Vertical flow path for 72 ... Case side vertical flow path, 73 ... Air opening port for accommodation space, 75 ... Horizontal flow path for compliance space, 76 ... Vertical flow path for compliance space, 77 ... Air opening port for compliance space, 80a ... 1st piezoelectric element row accommodation space air opening, 80b ... 2nd piezoelectric element row accommodation space air opening, 81a ... 1st compliance space air opening, 81b ... 2nd compliance space air opening, 82a ... 1st piezoelectric element row accommodating space open air path, 82b ... 2nd piezoelectric element row accommodating space atmospheric open path, 83a ... 1st compliant space open air path, 83b ... 2nd compliant space open air path, 84 … Case flow path for accommodation space, 85 ... Case flow path for compliance space, 87 ... Recording head unit, 88 ... Fixing member, 91 ... Liquid injection head, 92a ... Compliance space, 92b ... Compliance space, 93a ... Piezoelectric element accommodation space, 93b ... Piezoelectric element accommodation space, 94 … Open to the atmosphere, 95… Internal flow path, 96… Common open path to the atmosphere

Claims (9)

A liquid injection head having a nozzle opened on the nozzle surface and a liquid flow path communicating with the nozzle, and driving a driving element to inject liquid from the nozzle.
A first space isolated from the liquid flow path and provided with a driving element,
A second space isolated by a sealing membrane that is flexible with respect to the liquid flow path,
The first open air passage that communicates with the first space,
A second open air passage that communicates with the second space,
With
The first open path to the atmosphere has a higher flow path resistance than the second open path to the atmosphere.
A liquid injection head characterized in that the first open path to the atmosphere and the second open path do not communicate with each other. The first atmosphere opening path and the second atmosphere opening path are commonly formed from the atmosphere opening port communicating with the atmosphere to the branch in the middle.
The first branch flow path from the branch to the first space is a second flow path from the branch to the second space.
The liquid injection head according to claim 1, wherein the flow path resistance is higher than that of the branch flow path. The liquid injection head according to claim 2, wherein the first branch flow path includes a partial flow path extending from the first space along the nozzle surface. The liquid injection head according to claim 2, wherein at least a part of the first branch flow path is formed between the first space and the nozzle surface. A liquid injection head having a nozzle opened on the nozzle surface and a liquid flow path communicating with the nozzle, and driving a driving element to inject liquid from the nozzle.
A first space isolated from the liquid flow path and provided with a driving element,
A second space isolated by a sealing membrane that is flexible with respect to the liquid flow path,
The first open air passage that communicates with the first space,
A second open air passage that communicates with the second space,
With
The first open path to the atmosphere has a higher flow path resistance than the second open path to the atmosphere.
A first liquid flow path communicating with a first nozzle group consisting of a plurality of nozzles,
A second liquid flow path communicating with a second nozzle group composed of a plurality of nozzles formed apart from the first nozzle group,
A first drive element group composed of drive elements provided for each nozzle of the first nozzle group, and
A second drive element group composed of drive elements provided for each nozzle of the second nozzle group, and
A first space for the first drive element group, which is a kind of the first space for accommodating the first drive element group, and
A first space for a second drive element group, which is a kind of the first space for accommodating the second drive element group, and
The second space in which moisture easily enters from the first liquid flow path than in the first space for the first driving element group.
The second space on the first liquid flow path side, which is a kind of space,
The second space in which moisture easily enters from the second liquid flow path than in the first space for the second driving element group.
A second space on the second liquid flow path side, which is a kind of space, is provided.
The first atmosphere opening path on the first driving element group side that opens the first space for the first driving element group to the atmosphere, and the first atmosphere on the second driving element group side that opens the first space for the second driving element group to the atmosphere. The open path is a first open path common to the first open path to the atmosphere on the first drive element group side and the first open path to the atmosphere on the second drive element group side.
Communicated with the atmosphere through the air opening for space
The first liquid flow path side second atmosphere opening path that opens the first liquid flow path side second space to the atmosphere and the second liquid flow path side second atmosphere opening path that opens the second liquid flow path side second space to the atmosphere , A liquid injection characterized in that it is communicated with the atmosphere through a second space open port common to the first liquid flow path side second atmosphere open path and the second liquid flow path side second atmosphere open path. head. The first nozzle group and the second nozzle group are arranged along the first direction.
The liquid injection head according to claim 5, wherein the first space opening port and the second space opening port are formed so as to be separated from each other in the first direction. The first atmospheric open path on the first drive element group side is the nose from the first space for the first drive element group.
It is provided with a partial flow path on the side of the first drive element group extending along the surface.
The first open path to the atmosphere on the second drive element group side is characterized by including a partial flow path on the second drive element group side extending from the first space for the second drive element group along the nozzle surface. The liquid injection head according to claim 5 or 6. At least a part of the first atmospheric opening path on the first driving element group side is formed between the first space for the first driving element group and the nozzle surface.
5. Claim 5 or claim, wherein at least a part of the first atmospheric open path on the second drive element group side is formed between the first space for the second drive element group and the nozzle surface. Item 6. The liquid injection head according to item 6. A liquid injection head unit having a nozzle opened on a nozzle surface and a liquid flow path communicating with the nozzle, and having a plurality of liquid injection heads for driving a driving element to inject liquid from the nozzle.
The liquid injection head
A first space isolated from the liquid flow path and provided with a driving element,
A second space isolated by a sealing membrane that is flexible with respect to the liquid flow path,
The first open air passage that communicates with the first space,
A second open air passage that communicates with the second space,
With
The first open path to the atmosphere has a higher flow path resistance than the second open path to the atmosphere.
In the adjacent liquid injection heads, the distance between the air opening where the second space of one liquid injection head communicates with the atmosphere and the air opening where the second space of the other liquid injection head communicates with the atmosphere is A liquid injection head unit characterized in that the distance between the atmosphere opening port in which the first space communicates with the atmosphere and the atmosphere opening port in which the second space communicates with the atmosphere in the same liquid injection head is narrower.

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