JP2003011356A - Ink jet printer head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent intrusion of ink liquid from the open part of a hole 56 leading to the atmosphere made in a damper chamber 11a provided in a multilayer cavity plate unit in order to prevent crosstalk. SOLUTION: A cavity plate unit comprises a base plate 14 provided with a pressure chamber 16, a manifold plate 12 provided with a manifold chamber 12a for storing ink from an ink supply and then supplying ink to each pressure chamber 16, a spacer plate 13 sandwiched between the manifold plate 12 and the base plate 14, and a damper plate 11 sandwiched between a nozzle plate 43 provided with a nozzle 54 communicating with the pressure chamber 16 and the manifold plate 12 where all plates are laid in layers. The damper plate 11 is provided with a hole 56 communicating with a damper chamber 11a disposed to substantially overlaps the manifold chamber 12a such that the hole 56 opens to the atmosphere on the side where a piezoelectric actuator 20 is disposed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a piezoelectric type ink jet printer head.

[0002]

2. Description of the Related Art A prior art on-demand type piezoelectric ink jet printer head is disclosed in Japanese Patent Application Laid-Open No. 9-1.
As described in Japanese Patent No. 41856, a plurality of nozzles and a pressure chamber (ink cavity) for each nozzle.
And a diaphragm plate (flexible film) on the back surface of the cavity plate which is connected to the pressure chamber and supplies ink, and is selectively driven corresponding to the pressure chamber location through a diaphragm (flexible film) serving as a diaphragm. There is disclosed an inkjet printer head to which a cover plate having an energy generating portion such as a piezoelectric element for fixing is fixed.

When the energy generating portion such as the piezoelectric element is driven and vibrated, the pressure chamber is selectively pressurized through the vibrating plate, the pressure is propagated to the corresponding nozzle hole, and the ink droplet is ejected. The printing is executed by the ejection of. At this time, the pressure wave acting on the pressure chamber has not only a forward component toward the nozzle hole but also a backward component toward the ink manifold. Since the backward component causes so-called crosstalk, a damper device is provided to absorb and relax the backward component. That is, a damper chamber is formed in the cover plate at a position facing the ink manifold, and the vibrating plate (flexible film) is extended between the ink manifold and the damper chamber so that the vibrating plate (the flexible chamber) can be extended. It is separated from the ink manifold by a flexible film). Then, a vent hole (air vent hole) that connects the damper chamber to the atmosphere is formed on the side surface of the cover plate in the middle of the plate thickness.

[0004]

However, in the above configuration, the diaphragm (flexible film) is extended to partition the damper chamber from the ink manifold, so that the pressure chamber and the ink manifold are flat on one cavity plate. Only those formed in line can be applied. In such a configuration, since the pressure chambers, the ink manifolds, the energy generating portions such as the piezoelectric elements, and the damper chambers are arranged in a plane, the width of the head in the direction orthogonal to the nozzle row is increased, and one cavity plate is used. It is very difficult to three-dimensionally process the pressure chamber, the ink manifold, the communication hole to the nozzle, and the like, and a lot of man-hours are required.

On the other hand, the cavity plate is composed of a plurality of plate members, that is, a base plate provided with the pressure chambers, a manifold plate provided with the ink manifold, and a spacer plate interposed between the manifold plate and the base plate. And a nozzle plate provided with the nozzle is laminated. In this configuration, since the pressure chambers and the ink manifolds can be arranged so as to overlap vertically, the width of the head in the direction orthogonal to the nozzle row can be reduced, and the pressure chambers and the ink manifolds can be easily processed on each plate. it can. However, with this configuration, as described above, the damper chamber cannot be formed in the cover plate at the position facing the ink manifold. Further, if a part of the manifold plate forming the ink manifold is made thin so that it can be vibrated by a pressure wave, the rigidity of the head is partially reduced and the ejection characteristics of a plurality of nozzles vary. is there.

SUMMARY OF THE INVENTION The present invention has a technical object to provide an ink jet printer head which solves such a problem.

[0007]

In order to achieve this technical object, an ink jet printer head according to a first aspect of the present invention has a plurality of nozzles and pressure chambers for each nozzle arranged in a first direction. In the ink jet printer head, in which a cavity plate unit having a shape and an active portion that selectively drives each of the pressure chambers and that ejects ink are stacked, the cavity plate unit is A base plate provided with a pressure chamber, a manifold plate for accumulating ink from an ink supply source and then replenishing the pressure chambers at least partially overlapping the pressure chambers, and the manifold plate And a spacer plate interposed between the base plate and the base plate, and a spacer communicating with the pressure chamber. A nozzle plate which Le is provided,
The damper plate inserted between the manifold plate and the nozzle plate is laminated, and a damper chamber is formed in the damper plate so as to substantially overlap with the manifold chamber between the damper plate and the manifold plate. .

According to a second aspect of the present invention, in the ink jet printer head according to the first aspect, the other end of the communication hole communicating with the damper chamber is located at a position away from the nozzle arrangement side of the nozzle plate. It is formed to open to the atmosphere.

The invention described in claim 3 is the same as that of claim 2
In the inkjet printer head described in the paragraph 1, the communication hole is formed so as to be open to the atmosphere from the damper chamber along the plate thickness direction of the cavity plate unit and on the surface opposite to the nozzle plate disposition side. Is.

The invention according to claim 4 is the same as claim 1
The inkjet printer head according to any one of claims 1 to 3, wherein the manifold chamber in the manifold plate is a recess that opens only to the spacer plate side, and the damper chamber in the damper plate is a rear surface of the manifold chamber in the manifold plate. It is located on the side.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show a piezoelectric ink jet printer head of the present invention. In these drawings, a flexible flat cable 40 is superposed and joined to the upper surface of a plate type piezoelectric actuator 20 joined to the cavity plate unit 10 for connection with an external device. It is assumed that ink is ejected downward from the nozzles 54 opened on the lower surface side of the plate unit 10.

The cavity plate unit 10 according to the embodiment is constructed as shown in FIGS. 3 and 4. That is, the nozzle plate 43, the damper plate 11, the manifold plate 12, and the spacer plate 1
This is a structure in which five thin plates of 3 and the base plate 14 are stacked and bonded by adhesion. In the embodiment, each plate 11, 12, 13, 14 excluding the nozzle plate 43
Is made of 42% nickel alloy steel plate, 50 μm to 150 μm
It is about the thickness. Each plate is formed with openings or recesses that form the following channels or chambers by etching or the like. The nozzle plate 43 is provided with nozzles 54 for ejecting ink having a small diameter in two rows in a staggered arrangement along the first direction (long side direction) of the nozzle plate 43. That is, the nozzle plate 4
Two reference lines 43a, 43 parallel to the first direction of 3
A large number of nozzles 54 are formed in a zigzag arrangement along the line b at intervals of a fine pitch P.

Further, a pressure chamber 16 described later corresponding to each nozzle 54 and an active portion of a piezoelectric element in a piezoelectric actuator 20 described later are arranged so as to be vertically overlapped with each other in a plan view of each plate. The pressure chambers 16 are formed so as to extend in a direction intersecting (orthogonal to) the first direction, and the rows of the pressure chambers 16 extend along the first direction. A pair of manifold chambers 12a, 12a as ink passages are formed in the manifold plate 12 so as to extend along both sides of the row of the nozzles 54. In this case, each of the manifold chambers 12a extends so as to overlap the row of the pressure chambers 16 and to straddle the row of the pressure chambers 16 in a plan view of the plate (see FIGS. 3 and 4).

Each of the manifold chambers 12a in the manifold plate 12 corresponds to the manifold plate 1
2 is formed by a recess opened toward the upper spacer plate 13 leaving a thin bottom plate 12b on the lower surface side, and the lower surface of the spacer plate 13 and the upper surface of the manifold plate 12 are adhered to each other to form a hermetic seal. It has a structure (see FIG. 5).

The base plate 14 has a large number of narrow pressure chambers 16 extending in a second direction (short side direction) orthogonal to a center line along the long side (first direction) thereof. Has been drilled. Then, when the parallel longitudinal reference lines 14a and 14b are set on both the left and right sides of the center line, the tip 16a of the pressure chamber 16 on the left side of the center line is located on the left longitudinal reference line 14a. On the contrary, the tip 16a of the pressure chamber 16 on the right side of the longitudinal center line is located on the right longitudinal reference line 14b, and the pressure chambers 1 on the left and right sides
Since the tips 16a of 6 are alternately arranged, the pressure chambers 16 on both left and right sides are alternately arranged so as to extend in opposite directions (see FIG. 4).

The tips 16a of the pressure chambers 16 are provided with the staggered nozzles 54 in the nozzle plate 43.
Further, the spacer plate 13, the manifold plate 12 and the damper plate 11 are communicated with each other through through holes 17 having a minute diameter which are also formed in a staggered arrangement. On the other hand, the other end 16b of each pressure chamber 16 is connected to the manifold plate 1 through through holes 18 formed at both left and right sides of the spacer plate 13.
2 communicates with the manifold chamber 12a. The other end 16b is, as shown in FIG. 4, formed so as to be opened only on the lower surface side of the base plate 14. A filter 29 for removing dust in the ink supplied from an ink tank (not shown) above the supply hole 19a is provided on the upper surface of the supply hole 19a formed at one end of the uppermost base plate 14. Has been done.

As a result, supply holes 19a, 19 are formed from an ink supply source (ink tank) (not shown) at one end of the base plate 14 and the spacer plate 13.
The ink that has flowed into the left and right manifold chambers 12a, 12a via b is distributed into the pressure chambers 16 through the through holes 18, and then the through holes 17 are released from the pressure chambers 16. Through which the nozzle 54 corresponding to the pressure chamber 16 is reached (see FIGS. 3 and 5).

On the other hand, on the upper surface of the damper plate 11, a damper chamber 11a having substantially the same shape in plan view is formed at the substantially same position as each of the manifold chambers 12a so as to open upward. Therefore, when the manifold plate 12 and the damper plate 11 are joined together, the manifold chamber 12a and the damper chamber 11a are separated by the bottom plate 12b. Each of the damper chambers 11a includes a corresponding one of the manifold chambers 12 in plan view.
A communication portion 55 that bulges outward from the outer peripheral edge of a is formed.

Then, with the damper plate 11, the manifold plate 12, the spacer plate 13, and the base plate 14 laminated and fixed by bonding with an adhesive or the like, from the communicating portion 55 to the upper surface of the pace plate 14 (from the nozzle plate 43). A communication hole 56, which is an air escape hole that can communicate with the farthest side surface), is provided in each plate 1
The holes 2, 13 and 14 are preliminarily drilled. In order to exert the damper effect by the damper chamber 11a, it is preferably about 5 μm in the embodiment.

As shown in FIGS. 3 and 5, when the damper plate 11 is formed with a pair of damper chambers 11a, 11a, a communicating portion 55 and a communicating hole 56 are provided corresponding to each damper chamber 11a. Shall be formed, and also
When the piezoelectric actuator 20 to be described later is fixed to the upper surface of the pace plate 14 with an adhesive, the communication holes 56 should be set to open at locations not covered by the piezoelectric actuator 20 and the adhesive. .

On the other hand, the piezoelectric actuator 20 includes nine piezoelectric sheets 21 as shown in FIGS. 2, 5 and 6.
a, 21b, 21c, 21d, 21e, 21f, 21
g, 22, 23 are laminated, and the cavity is formed on the upper surface (wide surface) of the lowermost piezoelectric sheet 22 of the piezoelectric sheets and the odd-numbered piezoelectric sheets 21b, 21d, 21f counting upward from the piezoelectric sheet 22. A narrow individual electrode 24 is provided at each of the pressure chambers 16 in the plate unit 10.
The individual electrodes 24 are formed in rows along the first direction (long side direction), and the individual electrodes 24 extend along the second direction orthogonal to the first direction up to the vicinity of the edge of the long side of each piezoelectric sheet. It is extended.
Piezoelectric sheets 21a, 21c, 21e in even steps from the bottom,
A common electrode 25 common to the plurality of pressure chambers 16 is formed on the upper surface (wide surface) of 21 g.

In the embodiment, each of the individual electrodes 24 is
The width dimension of each is set to be slightly narrower than the wide portion of the corresponding pressure chamber 16 in plan view.

On the other hand, the pressure chambers 16 are arranged in two rows along the first direction (long side) on the central side of the short side of the base plate 14, so that the common electrode 25 is formed.
Is an even numbered piezoelectric sheet 21a, 21c, 21e, 2 so as to integrally cover the pressure chambers 16, 16 of the two rows.
It is formed in a substantially rectangular shape in plan view extending along the long side at the center of the short side direction of 1 g, and near the edge part of the short side of the pair of even-numbered piezoelectric sheets 21a, 21c, 21e, 21g. Draw-out portions 25a, 25a extending substantially over the entire length of the edge portion are integrally formed.

The even-numbered piezoelectric sheets 21
The same vertical position (corresponding position) as that of each individual electrode 24 is located on the surface near the edge of the long side of the pair of a, 21c, 21e, and 21g and where the common electrode 25 is not formed. Then, a dummy individual electrode 26 having substantially the same width and short length as the individual electrode 24 is formed. In this case, as shown in FIG. 6, the end of each dummy individual electrode 26 has a gap with an appropriate gap size with respect to the side edge of the common electrode 25 in the first direction (the direction along the long side). Separate. The length of every other layer of the dummy individual electrode 26 is set to L2 and L3 (<L
As shown in 2), the positions of the cuts of the pattern between the end portions of the dummy individual electrodes 26 and the side edges of the common electrode 25 are set every other sheet of the piezoelectric sheet in the second piezoelectric sheet.
It may be shifted in the direction (short side direction). In an embodiment,
Length L of the dummy individual electrode 26 in the second layer (piezoelectric sheet 21a) and the sixth layer (piezoelectric sheet 21e) from the bottom
2 is the length L of the dummy individual electrode 26 in the fourth layer (piezoelectric sheet 21c) and the eighth layer (piezoelectric sheet 21g).
It is set so as to be longer than 3 by the gap size.

On the other hand, the lowermost piezoelectric sheet 22 and the odd-numbered piezoelectric sheets 21b, 21d, 2 counting upward from the piezoelectric sheet 22.
Of the upper surface (wide surface) of 1f, the lead-out portion 25a,
The dummy common electrode 27 is formed at the position corresponding to 25a (the same vertical position, near the edges of the short sides of the pair of piezoelectric sheets).

A surface electrode 30 for each of the individual electrodes 24 and a surface electrode 31 for the common electrode 25 are provided on the upper surface of the uppermost top sheet 23 along the edges of the long sides thereof. It is provided (see FIG. 2).

Further, all the other piezoelectric sheets 21a, 21b, 21c, except the lowermost piezoelectric sheet 22.
21d, 21e, 21f, 21g and the top sheet 23 include the surface electrodes 30, the individual electrodes 24 and the dummy individual electrodes 26 at the corresponding positions (the same vertical position).
Through holes 32 are formed so that and communicate with each other. Similarly, the at least one surface electrode 31 (in the embodiment, the surface electrodes 3 at the four corners of the top sheet 23).
1) and the common electrode 25 at the position (the same vertical position) corresponding thereto or the lead-out portion 25a thereof communicate with each other.
Through the conductive material filled in 2, 33, the individual electrodes 24 of each layer and the surface electrodes 30 at positions corresponding to the individual electrodes 24.
Are electrically connected to each other, and similarly, the common electrodes 25 of each layer are electrically connected to each other and the surface electrode 31 at a position corresponding thereto.

As a result, the individual electrodes 24 and the dummy individual electrodes 26 at the same position on the top and bottom of the plurality of piezoelectric sheets 21 and the top sheet 23, which are vertically stacked, are the surface electrodes 30.
Of the surface electrode 31.
Will be electrically connected to the location (see FIGS. 2 and 6).
reference).

An adhesive sheet 41 made of an ink-impermeable synthetic resin material as an adhesive layer is formed on the entire lower surface (wide surface facing the pressure chamber 16) of the plate-type piezoelectric actuator 20 having such a structure. Affix in advance,
Next, with respect to the cavity plate unit 10, each individual electrode 2 in the piezoelectric actuator 20 is
4 are bonded and fixed so as to correspond to each pressure chamber 16 in the cavity plate unit 10 (see FIG. 5). Further, the flexible flat cable 4 is provided on the upper surface of the piezoelectric actuator 20.
By repeatedly pressing 0, various wiring patterns (not shown) in this flexible flat cable 40 are electrically joined to the respective surface electrodes 30, 31.

The material of the adhesive layer such as the adhesive sheet 41 is at least ink impermeable and electrically insulating, and is made of nylon-based or dimer acid-based polyamide resin. A film of polyamide-based hot-melt adhesive or polyester-based hot-melt adhesive as a main component may be used, but a polyolefin-based hot-melt adhesive is applied to the wide surface of the piezoelectric actuator 20. After that, it may be bonded and fixed to the cavity plate unit 10. The thickness of the adhesive layer is about 1 μm.

In this structure, any one of the individual electrodes 24 in the piezoelectric actuator 20 is selected.
By applying a voltage between the common electrode 25 and the common electrode 25, the piezoelectric element 21 has a piezoelectric element in which a distortion in the stacking direction is generated in the portion corresponding to the individual electrode 24 to which the voltage is applied. Becomes The active portion of the piezoelectric element in the piezoelectric actuator 20 and the nozzles 54
The pressure chamber 16 and the pressure chamber 16 overlap with each other in a plan view of each plate.

The internal volume of the pressure chamber 16 corresponding to each of the individual electrodes 24 is reduced by the strain of the active portion, so that the ink in the pressure chamber 16 is ejected from the nozzle 54 in a droplet form. Then, predetermined printing is performed.

As described above, by interposing the adhesive layer between the piezoelectric actuator 20 and the cavity plate unit 10 so as to cover all the pressure chambers 16, this adhesive layer does not allow ink to penetrate. In addition to serving as a coating, the piezoelectric actuator 20 and the cavity plate unit 10 can be firmly fixed together. Since it is an adhesive, the thickness of the layer can be made extremely thin as compared with the conventional diaphragm plate, and the inkjet printer head can be manufactured at low cost. Further, since the piezoelectric actuator 20 is formed by stacking the piezoelectric sheets 21 and 22 extending over the plurality of pressure chambers 16,
The rigidity of the piezoelectric actuator 20 as a whole is increased, and it is possible to drive at a high frequency without causing vibration unlike the conventional diaphragm plate.

When the active portion of the piezoelectric actuator 20 is selectively driven, the active portion elastically deforms so as to bend the flat surface of the plate portion of the piezoelectric actuator 20, and the predetermined pressure chamber 16 is selectively formed. The pressure is propagated to the corresponding nozzle hole 54, and printing is performed by ejecting ink droplets. At that time, the pressure wave acting on the pressure chamber 16 has not only a forward component toward the nozzle hole 54 but also a backward component toward the manifold chamber 12a. The backward component is the manifold chamber 12
The bottom plate 12b (see FIG. 5) having a small thickness of a vibrates greatly, and the air in the damper chamber 11a of the adjacent damper plate 11 absorbs and relaxes it. In that case, since the damper chamber 11a communicates with the atmosphere through the communication hole 56, there is almost no pressure fluctuation of the air in the damper chamber 11a, and the pressure wave is effectively absorbed in the manifold chamber 12a. So-called cross talk
It is possible to more effectively prevent the occurrence of the alk) phenomenon.

Further, the communication part 55 of the damper chamber 11a.
A plurality of plates 12, 13 and 14 that communicate with each other and are stacked
Since the communication hole 56 is provided so as to penetrate in the plate thickness direction and open on the side farther from the nozzle plate 43 (the rear surface of the base plate 14 and the side on which the piezoelectric actuator 20 is arranged), each When the plates 11, 12, 13, and 14 are bonded and fixed with an adhesive in a heated state, even if the air in the damper chamber 11a expands, it expands to the atmosphere through the communication part 55 and the communication hole 56. Since the air can be released, there is no inconvenience that the adhesive layer between the damper plate 11 and the manifold plate 12 is leaked (broken) in the expanded air flow passage.

Moreover, since the opening side of the communication hole 56 is located on the side farthest from the side where the nozzles 54 of the nozzle plate 43 are arranged, the atomized ink is ejected when the ink is ejected from the nozzles 54 during a normal printing operation. It can be surely prevented from entering the damper chamber 11a through the communication hole 56,
The chemical action of the ink in the damper chamber 11a has the effect of preventing accidents such as corrosion of the manifold plate 12 and erosion of the adhesive layer between the plates.

In the drive means (actuator) of the active portion for activating the pressure chambers according to the present invention, an individual piezoelectric element may be arranged for each pressure chamber.

[0038]

As described above, claim 1
The invention described in (1) has a cavity plate unit having a plurality of nozzles and pressure chambers for each nozzle in a row in the first direction, and an active part that can be selectively driven for each pressure chamber. Then, in an inkjet printer head in which an actuator for ejecting ink is laminated, the cavity plate unit is replenished in each pressure chamber after accumulating ink from a base plate provided with the pressure chamber and an ink supply source. A manifold plate provided at a position where at least a part of the manifold chamber overlaps the pressure chamber, a spacer plate interposed between the manifold plate and the base plate, and a nozzle communicating with the pressure chamber. Nozzle plate and a damper inserted between the manifold plate and the nozzle plate By the plates are stacked configuration, the damper chamber in the damper plate, and is formed so as to substantially overlap with the manifold chamber between the manifold plate.

Therefore, the pressure wave propagating to the ink in the manifold chamber due to the driving of the actuator is absorbed and relaxed by the air in the damper chamber which is recessed in the wall between the manifold chamber and the damper chamber and the adjacent damper plate. Let At this time, since the damper chamber is formed by the damper plate inserted between the manifold plate and the nozzle plate, the damper chamber can be easily provided in the laminated cavity plate unit without increasing its width. Further, even if the wall surface of the manifold plate forming the manifold chamber is made thin so that it can be deformed by a pressure wave, the rigidity of the entire head can be maintained, and the ejection characteristics of all nozzles can be uniformly stabilized. it can.

The invention described in claim 2 is the same as claim 1.
In the ink jet printer head described in the item (1), the other end of the communication hole communicating with the damper chamber is formed so as to be opened to the atmosphere at a position distant from the nozzle arrangement side of the nozzle plate.

When absorbing and relaxing the pressure wave, since the damper chamber communicates with the atmosphere through the communication hole, there is almost no pressure fluctuation of the air in the damper chamber, and the pressure wave is absorbed in the manifold chamber. Can be effectively performed, and the occurrence of a so-called crosstalk phenomenon can be prevented even more effectively.

Further, since the communication hole is preliminarily formed so as to communicate with the damper chamber, it is possible to release the expanded air in the damper chamber to the atmosphere when the plates are heated and bonded to each other so as to form the cavity plate. Therefore, it is possible to prevent the formation of ventilation passages in the adhesive layer between the plates.

Since the opening side of the communication hole is located on the side far from the nozzle arrangement side of the nozzle plate, the ink atomized when ejecting the ink from the nozzle during the normal printing operation passes through the communication hole. The effect of being able to reliably prevent it from invading into the damper chamber through the chemical action of the ink in the damper chamber, and to prevent accidents such as corrosion of the manifold plate or erosion of the adhesive layer between each plate. Play.

According to a third aspect of the present invention, in the ink jet printer head according to the second aspect, the communication hole extends from the damper chamber in the plate thickness direction of the cavity plate unit and the nozzle plate. It is formed so as to be open to the atmosphere on the surface opposite to the arrangement side.

As described above, since the communication hole is formed so as to extend along the plate thickness of the cavity plate unit, the communication surface can be achieved without greatly reducing the adhesive surface for stacking the plates of the cavity plate unit. The holes can be formed and the bonding strength does not decrease. Further, since the surface opposite to the side where the nozzle plate is arranged is opened to the atmosphere, it is possible to reliably prevent atomized ink from entering the damper chamber through the communication hole when ejecting the ink from the nozzle. .

The invention described in claim 4 is the same as claim 1
The inkjet printer head according to any one of claims 1 to 3, wherein the manifold chamber in the manifold plate is a recess that opens only to the spacer plate side, and the damper chamber in the damper plate is a rear surface of the manifold chamber in the manifold plate. Since it is located on the side, even if the manifold plate and the damper plate are stacked next to each other,
There is no communication between the manifold chamber and the damper chamber,
This has the effect of being able to reliably exert the damper effect.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a piezoelectric inkjet printer head according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view showing one end portions of a cavity plate unit and a piezoelectric actuator.

FIG. 3 is an exploded perspective view of a cavity plate unit.

FIG. 4 is a partially enlarged perspective view of a cavity plate unit.

5 is an enlarged side sectional view of the piezoelectric ink jet printer head shown in the line VV of FIG.

FIG. 6 is an exploded perspective view of a piezoelectric actuator.

[Explanation of symbols] 10 Cavity plate unit 11 damper plate 11a damper room 12 Manifold plate 12a Manifold chamber 13 Spacer plate 14 Base plate 16 Pressure chamber 20 Piezoelectric actuator 30, 31 Surface electrode 54 nozzles 55 Communication 56 communication hole 43 nozzle plate 54 nozzles

Claims (4)

[Claims] 1. A cavity plate unit having a plurality of nozzles and pressure chambers for each nozzle arranged in a row in a first direction, and an active part capable of being selectively driven for each pressure chamber. In an ink jet printer head in which an actuator for ejecting ink is stacked, the cavity plate unit is replenished to each pressure chamber after accumulating ink from a base plate provided with the pressure chamber and an ink supply source. A manifold plate provided at a position where the manifold chamber at least partially overlaps with the pressure chamber; and a spacer plate interposed between the manifold plate and the base plate,
A nozzle plate provided with a nozzle communicating with the pressure chamber, and a damper plate interposed between the manifold plate and the nozzle plate are laminated to form a damper chamber in the damper plate. An ink jet printer head, characterized in that it is formed so as to substantially overlap with the manifold chamber. 2. The method according to claim 1, wherein the other end of the communication hole communicating with the damper chamber is formed so as to open to the atmosphere at a position distant from the nozzle arrangement side of the nozzle plate. Inkjet printer head. 3. The communication hole is formed so as to be open to the atmosphere from the damper chamber along the plate thickness direction of the cavity plate unit and on the surface opposite to the nozzle plate disposition side. The inkjet printer head according to claim 2. 4. The manifold chamber of the manifold plate is a recess that is open only to the spacer plate side, and the damper chamber of the damper plate is located on the back side of the manifold chamber of the manifold plate. Claims 1 to 3
The inkjet printer head according to any one of 1.