JP2021154568A - Liquid blow molding device - Google Patents

Abstract

To provide a liquid blow molding device capable of accurately molding a plurality of containers at one time by one plunger pump.SOLUTION: The liquid blow molding device 1 that supplies pressurized liquid L to preform 2 for liquid blow molding into container C comprises: a plurality of molds 11; a plurality of blow nozzles 22; and one blow molding plunger pump 30 that supplies the pressurized liquid L to each blow nozzle 22, wherein the blow molding plunger pump 30 has a cylinder 31, a plunger 32, and a closure member 34 that partitions a pressure chamber 33 between the closing member and the plunger 32 and is provided with a plurality of blow molding outflow ports 37, each of which opens into the pressure chamber 33, and each of the plurality of blow nozzles 22 is connected to a corresponding blow molding outflow port 37 via piping 38.SELECTED DRAWING: Figure 3

Description

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

Synthetic resin containers such as polypropylene bottles and polyethylene terephthalate bottles (PET bottles) are used for various purposes such as beverages, foods, and cosmetics. In such a container, a synthetic resin preform formed into a bottomed tubular shape by injection molding or the like is heated to a temperature at which a stretching effect can be exhibited, and in this state, blown using a blow molding apparatus. 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 the pressurized air as the pressurized fluid supplied into the preform. According to the liquid blow molding apparatus, the step of filling the container with the content liquid is omitted by using the content liquid to be finally filled in the container as a product such as beverage, cosmetics, chemicals, etc. as the pressurized fluid. Therefore, the production process and the configuration of the production equipment can be simplified.

Conventionally, as such a liquid blow molding apparatus, for example, as described in Patent Document 1, a plurality of blow nozzles corresponding to a plurality of preforms and one additional blow nozzle connected to these blow nozzles via a pipe. A structure is known in which a pressure liquid source is provided and a plurality of preforms are simultaneously liquid blow molded.

Special Table 2017-501062

The plunger pump (pressurized liquid source) is generally provided with one outflow port, and when the plunger is activated, the pressurized liquid is discharged from the outflow port toward the blow nozzle in the pressure chamber. Is the target. Therefore, as described in Patent Document 1, in order to supply the pressurized liquid from one plunger pump to a plurality of blow nozzles, one pipe connected to the outflow port is inserted in the middle. It is necessary to branch into a plurality of pipes and connect the plurality of branched pipes to the corresponding blow nozzles.

However, in a configuration in which one pipe connected to the outflow port of the plunger pump is branched into a plurality of pipes in the middle and connected to a plurality of blow nozzles, the filling pressure and filling of the liquid supplied to each preform are filled. There was a risk that the amount would vary and the moldability of the container would not be stable.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a liquid blow molding apparatus capable of accurately molding a plurality of containers at once by one 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 liquid blow molds it into a container having a predetermined shape, and a plurality of gold pieces on which the preform is arranged. A plurality of blow nozzles engaged with the mold and the mouth portion of the preform arranged in the corresponding molds are connected to the respective blow nozzles via pipes and added to the respective blow nozzles. It has one blow molding plunger pump that supplies a pressurized liquid, and the blow molding plunger pump closes a cylinder, a plunger arranged inside the cylinder, and one end of the cylinder. A pressure chamber is partitioned from the plunger, and each of the blow nozzles has a closing member provided with a plurality of blow molding outflow ports that open into the pressure chamber. It is characterized in that it is connected to the corresponding blow molding outflow port via a pipe.

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

In the above configuration, the liquid blow molding apparatus of the present invention preferably includes a plurality of prefill channels for supplying a liquid to the corresponding preform before performing the liquid blow molding.

In the above configuration, the liquid blow molding apparatus of the present invention is provided with a plurality of prefill outflow ports, each of which opens into the pressure chamber and communicates with the corresponding prefill flow path via a pipe. It is preferable to have it.

In the above configuration, the liquid blow molding apparatus of the present invention further includes a prefill plunger pump that is connected to the prefill flow path via a pipe and supplies a pressurized liquid to each of the prefill flow paths. The prefill plunger pump has a cylinder, a plunger arranged inside the cylinder, and a closing member that closes one end of the cylinder and partitions a pressure chamber between the cylinder and the plunger. It is preferable that each of the closing members is provided with a plurality of prefill outflow ports that open into the pressure chamber and communicate with the corresponding prefill flow path via the pipe.

In the liquid blow molding apparatus of the present invention, in the above configuration, it is preferable that the plurality of prefill outflow ports are opened on the 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 for axially stretching the preforms arranged in the corresponding molds, and the plurality of prefill flow paths correspond to each other. It is preferable that it is configured to communicate with the corresponding preform through the axial center of the stretching rod.

According to the present invention, it is possible to provide a liquid blow molding apparatus capable of accurately molding a plurality of containers at once by one plunger pump.

It is explanatory drawing which shows the liquid blow molding apparatus which is one Embodiment of this invention. FIG. 5 is a cross-sectional view of the liquid blow molding apparatus shown in FIG. 1 in a side view showing the configuration of a liquid supply path between a blow molding plunger pump and two nozzle units. It is sectional drawing in plan view which shows the structure of the liquid supply path between a blow molding plunger pump and two nozzle units of the liquid blow molding apparatus shown in FIG. It is explanatory drawing which shows the liquid blow molding apparatus in the state which performs the prefill process. It is explanatory drawing which shows the liquid blow molding apparatus in the state which performs the liquid blow molding process. It is sectional drawing in the side view which shows the structure of the liquid supply path between the blow molding plunger pump and two nozzle units of the liquid blow molding apparatus of a modification. It is sectional drawing in plan view which shows the structure of the liquid supply path between the blow molding plunger pump and two nozzle units of the liquid blow molding apparatus of a modification.

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

The liquid blow molding apparatus 1 according to the embodiment of the present invention shown in FIG. 1 simultaneously supplies a plurality of preforms 2 with pressurized liquid L, and liquid blow molds these into a container having a predetermined shape. be. In the present embodiment, the liquid blow molding apparatus 1 simultaneously supplies the two preforms 2 with the pressurized liquid L, and the two preforms 2 are liquid blow molded 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 as each other. These preforms 2 are made of a thermoplastic synthetic resin material such as polypropylene (PP) or polyethylene terephthalate (PET), and have a cylindrical mouth portion 2a as an opening end and a lower end portion connected to the mouth portion 2a. Those formed in a shape having a closed bottomed cylindrical body portion 2b can be used.

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

The molded container is a liquid-containing container containing these liquids L as the content liquid.

The liquid blow molding apparatus 1 includes two blow molding units 10. Since the two blow molding units 10 have the same configuration as each other, 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. In the preform 2, the body portion 2b is arranged inside the cavity 11a of the mold 11, and the mouth portion 2a is arranged in the mold 11 in a posture in which the mouth portion 2a protrudes upward from the mold 11.

The mold 11 is configured to be openable to the left and right, for example, and the container can be taken out from the mold 11 by liquid blow molding the preform 2 into a container and then opening the mold 11 to the left and right. You can do it.

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 has 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 to which the liquid L is supplied when the liquid blow molding process is performed is provided so as to extend in the vertical direction. Further, the main body block 21 is provided with a connection port 24 communicating 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 with the mouth portion 2a of the preform 2 arranged in the mold 11 in a sealed state. do. When the blow nozzle 22 engages with the mouth portion 2a 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.

Inside the supply path 23, a first seal body 25 for opening and closing the blow nozzle 22 is arranged. The first seal body 25 is fixed to the lower end of the 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. 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 blocked by the first seal body 25, and the 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 is subjected to a step of supplying the liquid L to the corresponding preform 2 at a pressure lower than that of the liquid blow molding, that is, a prefilling step, before the liquid blow molding is performed. A prefill flow path 27 is provided. The prefill flow path 27 is provided at the axial center 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 flow path 27 can communicate with the inside of the preform 2 in a state where the blow nozzle 22 is engaged with the mouth portion 2a of the preform 2. The prefill flow path 27 is provided with a second seal body 28 for opening and closing the opening of the prefill flow path 27. The second seal body 28 is integrally provided at the lower end of the second shaft body 29 extending along the axial center of the prefill flow path 27, and moves in the vertical direction inside the prefill flow path 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 flow path 27 is closed by the second seal body 28, and the communication between the prefill flow path 27 and the preform 2 is established. It is blocked. On the other hand, when the second seal body 28 moves downward from the closed position, the opening of the prefill flow path 27 is opened, and the prefill flow path 27 and the preform 2 are communicated with each other.

The second seal body 28 and the second shaft body 29 function as stretching rods, and by moving downward, the preform 2 arranged 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 has one blow molding plunger pump 30 as a means for supplying the pressurized liquid L to each blow nozzle 22.

As shown in FIG. 2, the blow molding plunger pump 30 includes a cylinder 31, a plunger 32 movably arranged inside the cylinder 31 along the axial direction of the cylinder 31, and one end of the cylinder 31. It has a closing member 34 that closes and forms a pressure chamber 33 with the plunger 32. A support 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 35 so as to be movable in the axial direction. The plunger 32 can pressurize the liquid L stored in the pressure chamber 33 by being driven by the drive rod 36 and moving in the pressurizing direction (the side of the closing member 34), and the drive rod 36 can be pressed. The pressure chamber 33 can be made a negative pressure by being driven and moving in the suction direction (the side of the support 35).

The closing member 34 is provided with two blow molding outflow ports 37 corresponding to the two blow nozzles 22. Each of the two blow molding outflow ports 37 opens into the pressure chamber 33 and is connected to the connection port 24 of the nozzle unit 20 provided with the corresponding blow nozzle 22 by a separate pipe 38. That is, the two blow molding outflow ports 37 are connected to the corresponding blow nozzles 22 via the pipe 38, respectively. Therefore, when the plunger 32 operates and the liquid L stored in the pressure chamber 33 is pressurized while the first seal body 25 is opened, the liquid L becomes two blow molding outflow ports 37. Is supplied to the corresponding blow nozzle 22 via the pipe 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 each other.

As shown in FIG. 2, in the present embodiment, in the closing member 34, the two blow molding outflow ports 37 have an opening 37a to each pressure chamber 33, which is an extension range (plan) of the movement path of the plunger 32. It is arranged so as to be located within the range (range) S that overlaps with the plunger 32 when viewed from the direction along the axis O of the jar 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, and the axis O of the plunger 32. They are arranged so as to face each other with a.

As shown in FIG. 2, in the present embodiment, the top surface of the closing member 34 facing the plunger 32 is inclined in a conical shape about the axis O of the plunger 32, and the two blows. The openings 37a of the molding outflow port 37 are open to the inclined surface, respectively.

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 the supply tank 41 via a pipe 40. The supply tank 41 has a configuration in which the liquid L is accommodated and the liquid L is heated or cooled to a predetermined temperature to be held at the temperature, and the liquid L is supplied to the blow molding plunger pump 30 via the pipe 40. Can be supplied. The on-off valve 42 is provided in the pipe 40, and the on-off valve 42 closes the pipe 40 when the liquid blow molding step or the prefilling step is performed.

As shown in FIG. 3, in the present embodiment, the supply port 39 opens in the pressure chamber 33 at a position 90 degrees away from the two blow molding outflow ports 37 with respect to the axis O of the plunger 32. It is arranged to do.

As shown in FIGS. 1 and 2, in the present embodiment, the closing member 34 is opened to the pressure chamber 33 and communicates with the corresponding prefill flow path 27 via the pipe 43, respectively, for two prefill outflows. A port 44 is provided. The two prefill outflow ports 44 are opened to the pressure chamber 33 on the top surface of the closing member 34, respectively, within the extension range S of the movement path of the plunger 32.

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

First, the preform 2 heated to a temperature at which the stretching effect can be exhibited is placed in each mold 11.

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

Next, the liquid blow molding apparatus 1 performs a prefilling step of supplying the liquid L to the two preforms 2 in advance. In the prefilling step, 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 blow molding plunger pump 30 is operated in the pressurizing direction to allow the liquid L inside the pressure chamber 33 to flow from each of the two prefill outflow ports 44 via the pipe 43 to the prefill flow path 27. Supply to. The prefilling step is preferably carried out 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. Since the first seal body 25 is closed in the prefilling step, even if the plunger 32 of the blow molding plunger pump 30 operates in the pressurizing direction, the liquid L in the pressure chamber 33 is blown by two. It is not supplied to the nozzle 22 and the preform 2 is not liquid blow molded.

In the prefill step, the pressure of the liquid L supplied from the prefill flow path 27 to the inside of the preform 2 is preferably such that the preform 2 is not stretched by the pressure of the liquid L, but the pressure is arbitrary. It can be changed.

The liquid blow molding apparatus 1 may be configured to include a discharge flow path or the like for discharging the air extruded from the inside of the preform 2 by the liquid L to the outside in the prefill step.

When the prefilling step is completed, the liquid blow molding apparatus 1 then supplies the two preforms 2 with the pressurized liquid L to perform the liquid blow molding step. In the liquid blow molding step, 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, and blow is performed in this state. The plunger 32 of the molding plunger pump 30 is operated in the pressurizing direction to allow the liquid L inside the pressure chamber 33 to flow from each of the two blow molding outflow ports 37 to the pipe 38, the connection port 24 and the supply path 23. Is supplied to each blow nozzle 22 via. At this time, the pressure of the liquid L supplied by the blow molding plunger pump 30 to each blow nozzle 22 is set to a predetermined pressure suitable for blow molding (stretching) the preform 2. The liquid blow molding step is performed until the preform 2 has a shape along the cavity 11a of the mold 11.

In the present embodiment, the second seal body 28 is closed in the liquid blow molding step, but it may be opened.

As described above, in the liquid blow molding step, the liquid blow molding apparatus 1 simultaneously liquid blow molds two preforms 2 arranged in the corresponding molds 11 and forms them in a predetermined shape along the cavity 11a. It can be molded into container C.

As described above, since the liquid blow molding apparatus 1 can liquid blow mold two preforms 2 by one blow molding plunger pump 30, it can be made smaller and lighter.

Here, in the liquid blow molding apparatus 1 of the present embodiment, the blow molding plunger pump 30 has a closing member 34 that closes one end of the cylinder 31 to partition the pressure chamber 33 from the plunger 32. The closing member 34 is provided with two blow molding outflow ports 37 connected to corresponding blow nozzles 22 (connection ports 24) via pipes 38, respectively. In the liquid blow molding apparatus 1 of the present embodiment having such a configuration, when the plunger 32 operates in the pressurizing direction and the liquid L is pressurized inside the pressure chamber 33, the pressurized liquid Since L is distributed to two blow forming outflow ports 37 in the pressure chamber 33, only one blow forming outflow port is provided in the closing member 34, and the flow path is branched at the piping portion. As compared to the case, the pressurized liquid L will be evenly supplied to the corresponding blow nozzles 22 through the respective blow forming outflow ports 37.

As described above, according to the liquid blow molding apparatus 1 of the present embodiment, in the liquid blow molding step, one blow molding plunger pump 30 to two preforms 2 have substantially the same length (contents). Since the liquid L can be supplied with a uniform filling pressure or filling amount through the pipe 38 of the product), two containers C can be accurately molded at one time by one blow molding plunger pump 30.

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

Further, 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 so as to face each other with the axis O of the plunger 32 interposed therebetween. The liquid L pressurized in the chamber 33 can be ensured and evenly supplied by the corresponding blow nozzles 22 through the respective blow molding outflow ports 37. As a result, two containers C can be molded at one time with higher accuracy by one blow molding plunger pump 30.

Further, the liquid blow molding apparatus 1 of the present embodiment has two prefill flows for supplying the liquid L to the corresponding preform 2 at a lower pressure than that at the time of liquid blow molding before performing the liquid blow molding. Since the configuration is provided with the passage 27, the liquid blow molding can be performed after the inside of the preform 2 is filled with the liquid L by the prefilling step. As a result, during liquid blow molding, when the pressurized liquid L is supplied to the inside of the preform 2, the air inside the preform 2 is caught in the liquid L and the filling pressure inside the preform 2 is filled. Alternatively, it is possible to suppress the instability of the filling amount and mold two containers C at a time with one blow molding plunger pump 30 with higher accuracy.

In particular, in the liquid blow molding apparatus 1 of the present embodiment, the closing member 34 of the blow molding plunger pump 30 is opened to the pressure chamber 33 and communicates with the corresponding prefill flow path 27 via the pipe 43. Since one prefill outflow port 44 is provided, both the prefill step and the liquid blow molding step can be performed by one blow molding plunger pump 30. This makes it possible to simplify the configuration of the liquid blow molding apparatus 1 and reduce its cost.

Further, in the liquid blow molding apparatus 1 of the present embodiment, the two outflow ports 44 for prefilling are provided so as to be opened on the top surface of the closing member 34 facing the plunger 32, and therefore for each prefilling. The liquid L is supplied at a uniform pressure through the pipe 38 having substantially the same length (internal volume) to the two prefill flow paths 27 via the outflow port 44, and each preform 2 is supplied in the prefill step. It is possible to accurately fill the inside of the liquid L with a specified amount of liquid L.

Further, in the liquid blow molding apparatus 1 of the present embodiment, the second seal body 28 and the second shaft body 29 which also function as stretching rods for extending the preform 2 arranged in the corresponding molds 11 in the axial direction, respectively. The two prefill flow paths 27 are configured to communicate with the corresponding preform 2 through the axes of the corresponding second seal body 28 and the second shaft body 29, respectively. The configuration of the road 27 can be simplified to reduce the cost of the liquid blow molding apparatus 1.

FIG. 6 is a side view showing the configuration of the liquid supply path between the blow molding plunger pump and the two nozzle units of the liquid blow molding apparatus of the modified example, and FIG. 7 is a side view. It is sectional drawing in the plan view which shows the structure of the liquid supply path between a blow molding plunger pump and two nozzle units of the liquid blow molding apparatus of a modification. In FIGS. 6 and 7, the members corresponding to the above-mentioned members are designated by the same reference numerals.

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

In this case, as the blow molding plunger pump 30, a blow molding plunger pump 30 shown in FIGS. 1 to 5 has a configuration in which the closing member 34 is not provided with the prefill outflow port 44. be able to. On the other hand, as the prefill plunger pump 50, the blow molding plunger pump 30 shown in FIGS. 1 to 5 has a configuration in which the blow molding outflow port 37 is not provided in the closing member 34. Can be done.

In this way, the liquid blow molding apparatus 1 is configured to include the prefill plunger pump 50 in addition to the blow molding plunger pump 30, so that the prefill process can be performed from, for example, the blow molding plunger pump 30. It is also possible to use the dedicated prefill plunger pump 50, which has a slow operating speed of the plunger 32, and perform the liquid blow molding step with the dedicated blow molding plunger pump 30. Therefore, as in the present embodiment, the prefill flow path 27 is composed of 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 the prefill process, the pressure inside the prefill flow path 27 rises excessively with the start of the prefill step, and as a result, the pressure in the pressure chamber 33 also rises, causing the preform 2 to burst into the preform 2 and the core in the blow molding step. It is possible to prevent the container C from being displaced and the moldability of the container C from being lowered.

It goes without saying that the present invention is not limited to the above-described embodiment and can be variously modified without departing from the gist thereof.

For example, in the above embodiment, the liquid blow molding apparatus 1 has two molds 11 and two blow nozzles 22 for blow molding two preforms 2 into the container C at the same time. 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, but the present invention is not limited to this, and three or more preforms 2 can be simultaneously used. It has three or more molds 11 and three or more blow nozzles 22 for liquid blow molding in the container C, and corresponds to three or more blow nozzles 22 in the closing member 34 of the blow molding plunger pump 30. It is also possible to have a configuration in which three or more blow molding outflow ports 37 are provided. Even in this case, a plurality of preforms 2 can be accurately blow-molded into the container C at a time by one blow molding plunger pump 30.

Further, the liquid blow molding apparatus 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, or a prefilling outflow port 44 is provided on the peripheral wall of the closing member 34. May be good.

Further, in the above-described embodiment, a plurality of prefill flow paths 27 are provided at the axial centers 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 are provided. The prefill flow path 27 may be provided in the center, or the pipe 43 may be connected to the supply path 23 so that the supply path 23 can also be used as the prefill flow path 27.

Further, in the above-described embodiment, the liquid blow molding apparatus 1 is provided with a plurality of prefill flow paths 27 in order to perform a prefill step of supplying the liquid L to the corresponding preform 2 before performing the liquid blow molding. However, the present invention is not limited to this, and a configuration may be configured in which a plurality of prefill flow paths 27 are not provided.

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

Further, in the above-described embodiment, the prefill flow path 27 is provided between the second shaft body 29 and the first shaft body 26 that function as the stretching rod, but the stretching rod is provided inside the first shaft body 26. A second shaft body 29 having a second seal body 28 is arranged inside the stretching rod, and a prefill flow path 27 is provided between the stretching rod and the second shaft body 29. good. In this case, the extension rod is extended to a position where its tip (lower end) is close to the bottom portion of the preform 2 arranged on the mold 11, and then the second seal body 28 is opened to perform the prefill process. You may try to do it.

1 Liquid blow molding device 2 Preform 2a Mouth 2b Body 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 Flow path 28 Second seal body (stretching rod)
29 Second axis (stretching rod)
30 Blow forming plunger Pump 31 Cylinder 32 Plunger 33 Pressure chamber 34 Closing member 35 Support 36 Drive rod 37 Blow forming outflow port 37a Opening 38 Piping 39 Supply port 40 Piping 41 Supply tank 42 On-off valve 43 Piping 44 For prefilling 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 a pressurized liquid to a preform and blow molds it into a container having a predetermined shape.
A plurality of molds, each of which is arranged with the preform,
A plurality of blow nozzles, each of which engages with the mouth of the preform arranged in the corresponding mold,
It has one blow molding plunger pump, which is connected to each of the blow nozzles via a pipe and supplies a pressurized liquid to each of the blow nozzles.
The blow molding plunger pump is
Cylinder and
With the plunger placed inside the cylinder,
It has a closing member that closes one end of the cylinder, forms a pressure chamber between the cylinder and the plunger, and is provided with a plurality of blow molding outflow ports that open into the pressure chamber.
A liquid blow molding apparatus, wherein a plurality of the blow nozzles are connected to the corresponding blow molding outflow ports via the pipes. The liquid blow molding apparatus according to claim 1, wherein the closing member is provided with two blow molding outflow ports facing 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 a liquid to the corresponding preform before performing the liquid blow molding. The liquid blow molding apparatus according to claim 3, wherein each of the closing members is provided with a plurality of prefill outflow ports that open into the pressure chamber and communicate with the corresponding prefill flow path via a pipe. Each is further provided with a prefill plunger pump which is connected to the prefill flow path via a pipe and supplies a pressurized liquid to each of the prefill flow paths.
The plunger pump for prefilling
Cylinder and
With the plunger placed inside the cylinder,
It has a closing member that closes one end of the cylinder and forms a pressure chamber between the cylinder and the plunger.
The liquid blow molding apparatus according to claim 3, wherein each of the closing members is provided with a plurality of prefill outflow ports that open into the pressure chamber and communicate with the corresponding prefill flow path via the pipe. .. The liquid blow molding apparatus according to claim 4 or 5, wherein the plurality of prefill outflow ports are open to the top surface of the closing member facing the plunger. A plurality of stretching rods for axially stretching the preforms arranged in the corresponding molds are provided.
The liquid blow according to any one of claims 3 to 6, wherein the plurality of prefill flow paths are configured to communicate with the corresponding preform through the axial center of the corresponding extension rod. Molding equipment.

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