JP7345417B2 - liquid blow molding equipment - Google Patents

Description

The present invention relates to a liquid blow molding apparatus that supplies pressurized liquid to a preform and performs liquid blow molding into a container of a predetermined shape.

BACKGROUND OF THE INVENTION Containers made of synthetic resin, such as polypropylene bottles and polyethylene terephthalate bottles (PET bottles), are used for various purposes such as beverages, foods, and cosmetics. Such containers are made by heating a synthetic resin preform formed into a bottomed cylinder by injection molding to a temperature that produces a stretching effect, and then blowing it in this state using a blow molding machine. It is generally formed into a predetermined shape by molding.

As a blow molding apparatus, a liquid blow molding apparatus is known in which a pressurized liquid (pressurized liquid) is used instead of pressurized air as a pressurized fluid supplied into a preform. According to the liquid blow molding device, the process of filling the container with the liquid content can be omitted by using the liquid content that is to be filled into the container as the final product of beverages, cosmetics, medicines, etc. as the pressurized fluid. Therefore, the production process and the configuration of the production equipment can be simplified.

Conventionally, such a liquid blow molding apparatus has a plurality of blow nozzles corresponding to a plurality of preforms and one additional blow molding device connected to these blow nozzles via piping, as described in Patent Document 1, for example. There is known a structure that includes a pressure liquid source and performs liquid blow molding of a plurality of preforms at the same time.

Special table 2017-501062 publication

A plunger pump (pressurized liquid source) generally has one outflow port, and when the plunger operates, pressurized liquid in a pressure chamber is sent out from the outflow port toward a blow nozzle. It is true. Therefore, as described in Patent Document 1, in order to supply pressurized liquid from one plunger pump to a plurality of blow nozzles, one piping connected to an outflow port must be connected midway. It is necessary to have a configuration in which the pipes are branched into a plurality of pipes and each of the branched pipes is connected to a corresponding blow nozzle.

However, in a configuration in which a single pipe connected to the outflow port of a plunger pump is branched into multiple pipes midway and connected to multiple blow nozzles, the filling pressure of the liquid supplied to each preform cannot be adjusted. There was a risk that the amount would vary and the moldability of the container would be unstable.

The present invention has been made in view of these problems, and its purpose is to provide a liquid blow molding device that can accurately mold a plurality of containers at once using a single plunger pump. be.

The liquid blow molding apparatus of the present invention is a liquid blow molding apparatus that supplies a pressurized liquid to a preform and performs liquid blow molding into a container of a predetermined shape. a mold, a plurality of blow nozzles that engage with the mouths of the preforms arranged in the corresponding molds, and a plurality of blow nozzles that are connected to each of the blow nozzles via piping and that are connected to the respective blow nozzles. one plunger pump for blow molding that supplies a pressurized liquid; the plunger pump for blow molding includes a cylinder; a plunger disposed inside the cylinder; and a plunger pump that closes one end of the cylinder. and a closing member that defines a pressure chamber between the plunger and is provided with a plurality of outflow ports for blow molding each opening into the pressure chamber; It is characterized in that it is connected to the corresponding outflow port for blow molding via piping.

In the liquid blow molding device of the present invention, in the above configuration, it is preferable that the closing member is provided with two blow molding outflow ports that face each other across the axis of the plunger.

Preferably, the liquid blow molding apparatus of the present invention has a plurality of prefill channels for supplying liquid to the corresponding preform before performing the liquid blow molding.

In the liquid blow molding apparatus of the present invention, in the above configuration, the closing member is provided with a plurality of prefill outflow ports each opening into the pressure chamber and communicating with the corresponding prefill flow path via piping. It is preferable to be there.

The liquid blow molding apparatus of the present invention has the above configuration, and further includes a prefill plunger pump that is connected to each of the prefill channels via piping and supplies pressurized liquid to each of the prefill channels, The prefill plunger pump includes a cylinder, a plunger disposed inside the cylinder, and a closing member that closes one end of the cylinder and defines a pressure chamber between the cylinder and the plunger, Preferably, the closing member is provided with a plurality of prefill outflow ports each opening into the pressure chamber and communicating with the corresponding prefill flow path via the piping.

In the liquid blow molding apparatus of the present invention, in the above configuration, it is preferable that the plurality of prefill outflow ports open on a top surface of the closing member facing the plunger.

In the above configuration, the liquid blow molding apparatus of the present invention includes a plurality of stretching rods that axially stretch the preforms arranged in the corresponding molds, and a plurality of the prefill flow paths each having a corresponding one. It is preferable that the stretching rod is configured to communicate with the corresponding preform through the axis thereof.

According to the present invention, it is possible to provide a liquid blow molding device that can mold a plurality of containers at once with high precision using one plunger pump.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory diagram showing a liquid blow molding apparatus that is an embodiment of the present invention. FIG. 2 is a cross-sectional side view showing the configuration of a liquid supply path between a blow molding plunger pump and two nozzle units of the liquid blow molding apparatus shown in FIG. 1 . FIG. 2 is a cross-sectional plan view showing the configuration of a liquid supply path between a blow molding plunger pump and two nozzle units of the liquid blow molding apparatus shown in FIG. 1 . It is an explanatory view showing a liquid blow molding apparatus in a state where a prefill process is performed. It is an explanatory view showing a liquid blow molding apparatus in a state of performing a liquid blow molding process. FIG. 7 is a cross-sectional side view showing the configuration of a liquid supply path between a blow molding plunger pump and two nozzle units in a liquid blow molding apparatus according to a modified example. It is a sectional view in plan view showing the configuration of a liquid supply path between a blow molding plunger pump and two nozzle units of a liquid blow molding apparatus of a modified example.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

A liquid blow molding apparatus 1 shown in FIG. 1, which is an embodiment of the present invention, simultaneously supplies a pressurized liquid L to a plurality of preforms 2 and liquid blow molds them into containers of a predetermined shape. be. In this embodiment, the liquid blow molding apparatus 1 is configured to simultaneously supply pressurized liquid L to two preforms 2 and liquid blow mold these two preforms 2 into containers having the same predetermined shape. It has become.

The two preforms 2 are each made of synthetic resin and have the same shape. These preforms 2 are made of a thermoplastic synthetic resin material such as polypropylene (PP) or polyethylene terephthalate (PET), and have a cylindrical opening 2a that is an open end, and a lower end that is connected to the opening 2a. It is possible to use one formed in a shape having a closed-bottomed cylindrical body portion 2b.

The liquid L may be various liquids, such as beverages, liquid foods such as soy sauce, cosmetics, medicines, detergents, and toiletries such as shampoo.

The molded container is a liquid-filled container containing these liquids L as contents.

The liquid blow molding apparatus 1 includes two blow molding units 10. Since the two blow molding units 10 have the same configuration, one blow molding unit 10 will be described below.

The blow molding unit 10 has a mold 11 for blow molding. The mold 11 has a cavity 11a having a shape corresponding to the final shape of the container, such as a bottle shape. The cavity 11a opens upward on the upper surface of the mold 11. The preform 2 is placed in the mold 11 in such a manner that the body portion 2b is placed inside the cavity 11a of the mold 11 and the mouth portion 2a protrudes upward from the mold 11.

The mold 11 has a structure that can be opened left and right, for example, and after liquid blow molding the preform 2 into a container, the container can be taken out from the mold 11 by opening the mold 11 left and right. It is now possible to do so.

The blow molding unit 10 includes a nozzle unit 20. The nozzle unit 20 is arranged above the mold 11 and is movable relative to the mold 11 in the vertical direction.

The nozzle unit 20 includes a main body block 21 and a blow nozzle 22 fixed to the lower end of the main body block 21. Inside the main body block 21, a supply path 23 is provided extending in the vertical direction, through which the liquid L is supplied during the liquid blow molding process. Furthermore, the main body block 21 is provided with a connection port 24 that communicates with the upper end of the supply path 23 . The blow nozzle 22 communicates with the supply path 23, and when the nozzle unit 20 descends to the lower stroke end, it engages in a sealed state with the mouth 2a of the preform 2 placed in the mold 11. do. When the blow nozzle 22 engages with the mouth portion 2 a of the preform 2 , the liquid L supplied to the supply path 23 can be supplied to the preform 2 via the blow nozzle 22 .

A first seal body 25 for opening and closing the blow nozzle 22 is arranged inside the supply path 23 . The first seal body 25 is fixed to the lower end of a first shaft body 26 provided in the nozzle unit 20 so as to be movable in the vertical direction, and is movable in the vertical direction inside the supply path 23 . Note that the first seal body 25 may be formed integrally with the first shaft body 26. When the first seal body 25 is in the closed position, which is the lower stroke end position, the blow nozzle 22 is closed by the first seal body 25, and communication between the supply path 23 and the preform 2 is cut off. On the other hand, when the first seal body 25 moves upward from the closed position, the blow nozzle 22 is opened and the supply path 23 and the preform 2 are communicated with each other.

In the present embodiment, the nozzle unit 20 includes, before liquid blow molding, a step of supplying the liquid L to the corresponding preform 2 at a lower pressure than during liquid blow molding, that is, a prefill step. A prefill channel 27 is provided. The prefill channel 27 is provided at the axes of the first seal body 25 and the first shaft body 26, and is open at the lower end of the first seal body 25. The opening of the prefill channel 27 can communicate with the inside of the preform 2 when the blow nozzle 22 is engaged with the mouth 2 a of the preform 2 . The prefill channel 27 is provided with a second seal body 28 for opening and closing the opening of the prefill channel 27 . The second seal body 28 is integrally provided at the lower end of a second shaft body 29 extending along the axis of the prefill channel 27, and moves in the vertical direction inside the prefill channel 27 together with the second shaft body 29. It is free. When the second seal body 28 is in the closed position, which is the upper stroke end position, the opening of the prefill channel 27 is closed by the second seal body 28, and communication between the prefill channel 27 and the preform 2 is interrupted. Be cut off. On the other hand, when the second seal body 28 moves downward from the closed position, the opening of the prefill channel 27 is opened, and the prefill channel 27 and the preform 2 are communicated with each other.

The second seal body 28 and the second shaft body 29 function as a stretching rod, and by moving downward, the preform 2 placed in the mold 11 can be stretched in the axial direction. can.

As described above, the liquid blow molding apparatus 1 includes two molds 11 and two blow nozzles 22 corresponding to the two preforms 2.

On the other hand, the liquid blow molding apparatus 1 includes one blow molding plunger pump 30 as a means for supplying pressurized liquid L to each blow nozzle 22.

As shown in FIG. 2, the plunger pump 30 for blow molding includes a cylinder 31, a plunger 32 disposed inside the cylinder 31 so as to be movable along the axial direction of the cylinder 31, and one end of the cylinder 31. It has a closing member 34 which is closed to define a pressure chamber 33 between the plunger 32 and the plunger 32 . A support body 35 is fixed to the other end of the cylinder 31, and a drive rod 36 provided integrally with the plunger 32 is supported by the support body 35 so as to be movable in the axial direction. The plunger 32 is driven by the drive rod 36 and moves in the pressurizing direction (to the side of the closing member 34 ), thereby being able to pressurize the liquid L stored in the pressure chamber 33 . By being driven and moving in the suction direction (toward the support body 35), the pressure chamber 33 can be made to have a negative pressure.

The closing member 34 is provided with two blow molding outflow ports 37 corresponding to the two blow nozzles 22 . The two blow molding outflow ports 37 each open into the pressure chamber 33 and are connected to the connection port 24 of the nozzle unit 20 provided with the corresponding blow nozzle 22 through separate piping 38 . That is, the two blow molding outflow ports 37 are each connected to the corresponding blow nozzle 22 via the piping 38. Therefore, when the plunger 32 is operated and the liquid L stored in the pressure chamber 33 is pressurized in the state where the first seal body 25 is opened, the liquid L is transferred to the two blow molding outflow ports 37. is supplied to the corresponding blow nozzle 22 via piping 38. The lengths (internal volumes) of the two pipes 38 connected between the blow molding outflow port 37 and the corresponding blow nozzle 22 are substantially the same.

As shown in FIG. 2, in the present embodiment, in the closing member 34, the two blow molding outflow ports 37 have openings 37a to the respective pressure chambers 33 extending in the extension range of the moving path of the plunger 32 (planning). The plunger 32 is arranged so as to be located within a range S (a range overlapping with the plunger 32) when viewed from the direction along the axis O of the plunger 32.

Further, as shown in FIGS. 2 and 3, in the present embodiment, in the closing member 34, the two blow molding outflow ports 37 have openings 37a to the respective pressure chambers 33 aligned with the axis O of the plunger 32. They are placed facing each other with the two sides in between.

In addition, as shown in FIG. 2, in this embodiment, the top surface of the closing member 34 facing the plunger 32 is inclined in a conical shape centered on the axis O of the plunger 32, and the top surface of the closing member 34 faces the plunger 32. The openings 37a of the molding outflow ports 37 are open to the respective inclined surfaces.

As shown in FIG. 3, the closing member 34 is provided with a supply port 39 for supplying the liquid L to the pressure chamber 33. As shown in FIG. 1, the supply port 39 is connected to a supply tank 41 via piping 40. The supply tank 41 is configured to contain the liquid L and to heat or cool the liquid L to a predetermined temperature and maintain it at the temperature. can be supplied. The piping 40 is provided with an on-off valve 42, and the piping 40 is closed by the on-off valve 42 when performing a liquid blow molding process or a prefilling process.

As shown in FIG. 3, in this embodiment, the supply port 39 opens into the pressure chamber 33 at a position shifted by 90 degrees about the axis O of the plunger 32 with respect to the two blow molding outflow ports 37. It is arranged so that

As shown in FIGS. 1 and 2, in this embodiment, the closing member 34 has two prefill outflows each opening into the pressure chamber 33 and communicating with the corresponding prefill flow path 27 via the piping 43. A port 44 is provided. The two prefill outflow ports 44 each open into the pressure chamber 33 within the extension range S of the movement path of the plunger 32 on the top surface of the closing member 34 .

Next, a process of liquid blow molding a synthetic resin preform 2 into a container of a predetermined shape using the liquid blow molding apparatus 1 having such a configuration will be described.

First, a preform 2 heated to a temperature that can produce a stretching effect is placed in each mold 11.

Next, the liquid blow molding apparatus 1 is brought into a state in which the first seal body 25 and the second seal body 28 are closed and the on-off valve 42 is opened in each nozzle unit 20, and in this state, the blow molding plunger is The plunger 32 of the pump 30 is operated in the suction direction to fill the pressure chamber 33 with a predetermined amount of liquid L (the state shown in FIG. 1).

Next, the liquid blow molding apparatus 1 performs a prefill process of supplying the liquid L to the two preforms 2 in advance. In the prefill process, as shown in FIG. 4, in each nozzle unit 20, the second seal body 28 is opened, the first seal body 25 is closed, and the on-off valve 42 is closed. The plunger 32 of the plunger pump 30 for blow molding is actuated in the pressurizing direction, and the liquid L inside the pressure chamber 33 is sent to the prefill channel 27 from each of the two prefill outflow ports 44 via the piping 43. supply to. The prefill step is preferably performed until the inside of the preform 2 is filled with the liquid L. As a result, all the air inside the preform 2 is replaced with the liquid L. Note that in the prefill process, the first seal body 25 is closed, so even if the plunger 32 of the plunger pump 30 for blow molding operates in the pressurizing direction, the liquid L in the pressure chamber 33 is It is not supplied to the nozzle 22 and the preform 2 is not liquid blow molded.

In the prefill process, the pressure of the liquid L supplied into the preform 2 from the prefill channel 27 is preferably such that the preform 2 is not stretched by the pressure of the liquid L, but the pressure may be set arbitrarily. Can be changed.

The liquid blow molding apparatus 1 can also be configured to include a discharge channel for discharging air pushed out from the inside of the preform 2 by the liquid L to the outside in the prefill process.

When the prefill process is completed, next, the liquid blow molding device 1 supplies the pressurized liquid L to the two preforms 2 to perform the liquid blow molding process. In the liquid blow molding process, as shown in FIG. 5, in each nozzle unit 20, the first seal body 25 is opened, the second seal body 28 is closed, and the on-off valve 42 is closed. By operating the plunger 32 of the molding plunger pump 30 in the pressurizing direction, the liquid L inside the pressure chamber 33 is transferred from each of the two blow molding outflow ports 37 to the piping 38, the connection port 24, and the supply path 23. is supplied to each blow nozzle 22 via the. At this time, the pressure of the liquid L supplied to each blow nozzle 22 by the blow molding plunger pump 30 is set to a predetermined pressure suitable for blow molding (stretching) the preform 2. The liquid blow molding process is performed until the preform 2 has a shape that follows the cavity 11a of the mold 11.

In this embodiment, the second seal body 28 is closed during the liquid blow molding process, but it may be open.

As described above, in the liquid blow molding process, the liquid blow molding device 1 simultaneously liquid blow molds two preforms 2 placed in the corresponding molds 11, and molds them into a predetermined shape along the cavity 11a. It can be formed into a container C.

In this manner, the liquid blow molding apparatus 1 can perform liquid blow molding of two preforms 2 using one plunger pump 30 for blow molding, and thus can be made smaller and lighter.

Here, in the liquid blow molding apparatus 1 of the present embodiment, the plunger pump 30 for blow molding has a closing member 34 that closes one end of the cylinder 31 to define a pressure chamber 33 between it and the plunger 32. The closing member 34 is provided with two blow molding outflow ports 37 each connected to the corresponding blow nozzle 22 (connection port 24) via a pipe 38. In the liquid blow molding apparatus 1 of this embodiment having such a configuration, when the plunger 32 operates in the pressurizing direction and pressurizes the liquid L inside the pressure chamber 33, the pressurized liquid Since L is distributed to two blow molding outflow ports 37 in the pressure chamber 33, only one blow molding outflow port is provided in the closing member 34, and the flow path is branched at the piping part. Compared to the case, the pressurized liquid L is evenly supplied to the corresponding blow nozzle 22 through each blow molding outflow port 37.

As described above, according to the liquid blow molding apparatus 1 of the present embodiment, one blow molding plunger pump 30 can be applied to two preforms 2 having substantially the same length (content) in the liquid blow molding process. Since the liquid L can be supplied at a uniform filling pressure or filling amount through the piping 38, two containers C can be molded at once with high precision using one plunger pump 30 for blow molding.

In particular, in the liquid blow molding apparatus 1 of the present embodiment, the two blow molding outflow ports 37 provided in the closing member 34 are located so that the openings 37a thereof are within the extension range S of the movement path of the plunger 32. Since the liquid L pressurized by the plunger 32 in the pressure chamber 33 is directly distributed to each blow molding outflow port 37 in the pressure chamber 33, the pressure is increased. The liquid L can be more reliably and evenly supplied to the corresponding blow nozzle 22 through the blow molding outflow port 37. Therefore, two containers C can be molded at once with higher accuracy using one plunger pump 30 for blow molding.

Furthermore, in the liquid blow molding apparatus 1 of the present embodiment, the two blow molding outflow ports 37 provided in the closing member 34 are arranged to face each other with the axis O of the plunger 32 interposed therebetween. It is possible to ensure that the pressurized liquid L in the chamber 33 is evenly supplied by the corresponding blow nozzle 22 through each blow molding outlet port 37. Thereby, two containers C can be molded at once with one blow molding plunger pump 30 with higher precision.

Furthermore, the liquid blow molding apparatus 1 of the present embodiment has two prefill streams for supplying the liquid L to the corresponding preform 2 at a pressure lower than that during liquid blow molding before performing liquid blow molding. Since the structure includes the passage 27, liquid blow molding can be performed after the inside of the preform 2 is filled with the liquid L in the prefill process. As a result, when the pressurized liquid L is supplied to the inside of the preform 2 during liquid blow molding, the air inside the preform 2 is drawn into the liquid L and the filling pressure inside the preform 2 is increased. It is possible to prevent the filling amount from becoming unstable and to mold two containers C at once with higher precision using one plunger pump 30 for blow molding.

Particularly, in the liquid blow molding apparatus 1 of the present embodiment, the closing member 34 of the plunger pump 30 for blow molding is provided with two pipes each opening into the pressure chamber 33 and communicating with the corresponding prefill channel 27 via the piping 43. Since two prefill outflow ports 44 are provided, one blow molding plunger pump 30 can perform both the prefill process and the liquid blow molding process. Thereby, the configuration of the liquid blow molding device 1 can be simplified and its cost can be reduced.

In addition, in the liquid blow molding apparatus 1 of the present embodiment, the two prefill outflow ports 44 are opened on the top surface of the closing member 34 facing the plunger 32, so that each prefill outflow port 44 is The liquid L is supplied at a uniform pressure to the two prefill flow paths 27 through the piping 38 having substantially the same length (inner volume) through the outflow port 44, so that the liquid L is supplied to each preform 2 in the prefill process. A prescribed amount of liquid L can be accurately filled into the inside of the container.

Furthermore, in the liquid blow molding apparatus 1 of the present embodiment, the second seal body 28 and the second shaft body 29 also function as stretching rods that axially stretch the preforms 2 placed in the corresponding molds 11. Since the two prefill channels 27 are configured to communicate with the corresponding preforms 2 through the axes of the corresponding second seal body 28 and second shaft body 29, the prefill flow is By simplifying the configuration of the channel 27, the cost of the liquid blow molding apparatus 1 can be reduced.

FIG. 6 is a cross-sectional side view showing the configuration of a liquid supply path between a blow molding plunger pump and two nozzle units in a liquid blow molding apparatus according to a modified example, and FIG. It is a sectional view in plan view showing the configuration of a liquid supply path between a blow molding plunger pump and two nozzle units of a liquid blow molding apparatus of a modified example. Note that in FIGS. 6 and 7, members corresponding to those described above are given the same reference numerals.

The liquid blow molding apparatus 1 can also be configured to include a prefill plunger pump 50 in addition to the blow molding plunger pump 30, as in the modification shown in FIGS. 6 and 7.

In this case, the blow molding plunger pump 30 used is one in which the blow molding plunger pump 30 shown in FIGS. 1 to 5 does not have the prefill outflow port 44 in the closing member 34. be able to. On the other hand, as the plunger pump 50 for prefilling, a plunger pump 50 for blow molding shown in FIGS. 1 to 5 may be configured such that the outflow port 37 for blow molding is not provided in the closing member 34. I can do it.

In this way, by configuring the liquid blow molding apparatus 1 to include the plunger pump 50 for prefill in addition to the plunger pump 30 for blow molding, the prefill process can be performed more easily than the plunger pump 30 for blow molding. The liquid blow molding process can also be performed using a dedicated prefill plunger pump 50 whose plunger 32 operates slowly, and the liquid blow molding process can be performed using a dedicated blow molding plunger pump 30. Therefore, as in the present embodiment, the prefill flow path 27 is constituted by a narrow flow path between the first shaft body 26 and the second shaft body 29, and a liquid L having a relatively high viscosity is used. In this case, in the prefill process, the pressure inside the prefill flow path 27 increases excessively at the start of the prefill process, and as a result, the pressure in the pressure chamber 33 also increases, causing the preform 2 to rupture and core in the blow molding process. It is possible to prevent the moldability of the container C from deteriorating due to misalignment.

It goes without saying that the present invention is not limited to the embodiments described above, and can be modified in various ways without departing from the spirit thereof.

For example, in the embodiment, the liquid blow molding apparatus 1 has two molds 11 and two blow nozzles 22 in order to simultaneously liquid blow mold two preforms 2 into a container C, and also has two molds 11 and two blow nozzles 22 for blow molding. Although the configuration is such that the closing member 34 of the plunger pump 30 is provided with two blow molding outflow ports 37 corresponding to the two blow nozzles 22, the present invention is not limited to this. In order to perform liquid blow molding on the container C, it has three or more molds 11 and three or more blow nozzles 22, and is compatible with the three or more blow nozzles 22 in the closing member 34 of the plunger pump 30 for blow molding. It is also possible to adopt a configuration in which three or more outflow ports 37 for blow molding are provided. Even in this case, a plurality of preforms 2 can be liquid-blow-molded into the container C at once with high precision using one plunger pump 30 for blow-molding.

Further, the liquid blow molding device 1 may have a configuration in which a plurality of blow molding outflow ports 37 are provided on the top wall of the closing member 34, and a configuration in which a prefill outflow port 44 is provided in the peripheral wall of the closing member 34. Good too.

Furthermore, in the embodiment described above, the plurality of prefill channels 27 are provided at the axes of the second seal body 28 and the second shaft body 29 that function as stretching rods, but other parts of the nozzle unit 20 The prefill channel 27 may be provided in the prefill channel 27 , or the pipe 43 may be connected to the supply channel 23 so that the supply channel 23 can also be used as the prefill channel 27 .

Furthermore, in the embodiment, the liquid blow molding apparatus 1 is configured to include a plurality of prefill channels 27 in order to perform a prefill step of supplying the liquid L to the corresponding preform 2 before performing liquid blow molding. However, the present invention is not limited to this, and a configuration that does not include the plurality of prefill channels 27 may also be possible.

Further, in the embodiment described above, the closing member 34 is fixed to one end of the cylinder 31, but may be formed integrally with the cylinder 31.

Furthermore, in the embodiment described above, the prefill channel 27 is provided between the second shaft body 29 functioning as a stretching rod and the first shaft body 26, but the stretching rod is provided inside the first shaft body 26. In addition, a second shaft body 29 provided with a second seal body 28 may be arranged inside the stretching rod, and a prefill channel 27 may be provided between the stretching rod and the second shaft body 29. good. In this case, after the stretching rod is extended to a position where its tip (lower end) is close to the bottom part of the preform 2 placed in the mold 11, the second seal body 28 is opened to perform the prefilling process. You may also do so.

1 Liquid blow molding device 2 Preform 2a Mouth part 2b Body part 10 Blow molding unit 11 Mold 11a Cavity 20 Nozzle unit 21 Main body block 22 Blow nozzle 23 Supply path 24 Connection port 25 First seal body 26 First shaft body 27 Prefill Channel 28 Second seal body (stretch rod)
29 Second shaft body (stretching rod)
30 Blow molding plunger pump 31 Cylinder 32 Plunger 33 Pressure chamber 34 Closure member 35 Support body 36 Drive rod 37 Blow molding outflow port 37a Opening 38 Piping 39 Supply port 40 Piping 41 Supply tank 42 Open/close valve 43 Piping 44 For prefill Outflow port 50 Plunger pump for prefill L Liquid S Extension range O Axis C Container

Claims (7)

A liquid blow molding device that supplies pressurized liquid to a preform and performs liquid blow molding into a container of a predetermined shape,
a plurality of molds in which the preforms are respectively placed;
a plurality of blow nozzles each engaging with a mouth portion of the preform disposed in the corresponding mold;
one blow molding plunger pump connected to each of the blow nozzles via piping and supplying pressurized liquid to each of the blow nozzles;
The plunger pump for blow molding is
cylinder and
a plunger disposed inside the cylinder;
a closing member that closes one end of the cylinder, defines a pressure chamber between the cylinder and the plunger, and is provided with a plurality of blow molding outflow ports each opening into the pressure chamber;
A liquid blow molding apparatus, wherein a plurality of the blow nozzles are each connected to a corresponding blow molding outflow port via the piping. The liquid blow molding device according to claim 1, wherein the closing member is provided with two blow molding outflow ports that face each other across the axis of the plunger. The liquid blow molding apparatus according to claim 1 or 2, further comprising a plurality of prefill channels for supplying liquid to the corresponding preforms before performing the liquid blow molding. 4. The liquid blow molding apparatus according to claim 3, wherein the closing member is provided with a plurality of prefill outflow ports each opening into the pressure chamber and communicating with the corresponding prefill flow path via piping. Further comprising a prefill plunger pump connected to each of the prefill channels via piping and supplying pressurized liquid to each of the prefill channels,
The prefill plunger pump is
cylinder and
a plunger disposed inside the cylinder;
a closing member that closes one end of the cylinder and defines a pressure chamber between it and the plunger;
The liquid blow molding apparatus according to claim 3, wherein the closing member is provided with a plurality of prefill outflow ports each opening into the pressure chamber and communicating with the corresponding prefill flow path via the piping. . The liquid blow molding apparatus according to claim 4 or 5, wherein the plurality of prefill outflow ports are open on a top surface of the closing member that faces the plunger. comprising a plurality of stretching rods that axially stretch the preforms placed in the corresponding molds,
The liquid blow according to any one of claims 3 to 6, wherein the plurality of prefill channels are configured to communicate with the corresponding preforms through the axes of the corresponding stretching rods. Molding equipment.

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