JP2012232593A - Compression molding die and compression molding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve layout of a die without requiring precision in positioning a slide insert die and a cavity die of a compression molding die.SOLUTION: The compression molding die includes a cavity die 34 having a neck ring of the compression molding die 33 and forming a lower part of a preform, a core die 35 for forming an inner surface of the preform, and a slide insert die 36 for forming an upper part of the preform. The compression molding die also includes a pressure holding part for adjusting the inner pressure of the molten resin by sliding a slide member 44 upon the compression molding. A circular protrusion 34b is formed in the periphery of the upper part of a molding hole 38 of the cavity die 34. The slide member 44 is arranged to vertically slide on the outer peripheral part of the circular protrusion 34b.

Description

  The present invention improves the quality of the molded body molded by the compression molding machine, and omits and simplifies the mold positioning structure of the compression molding machine that has been conventionally required by changing the mold structure. Alternatively, the present invention relates to a compression molding die and a compression molding method which are alleviated and further improved in accuracy.

Synthetic resin containers are widely used in daily life as containers for beverages and foods due to their light weight, economy, and excellent physical properties. In particular, containers (pet bottles) molded from polyethylene terephthalate (so-called PET) are in great demand as containers for soft drinks, beverages and foods due to their excellent mechanical properties and transparency. It is heavily used.
As described above, a synthetic resin container represented by polyethylene terephthalate is generally stretch blow molding in which a fluid (such as air) is blown into a preform (preliminarily formed bottomed cylindrical molding material) in a molding die. It is efficiently manufactured by a method (simply called stretch molding or blow molding).

  Conventionally, the injection molding method has been used to mold preforms, but a compression molding machine has been proposed as a molding device that can be downsized and molded at a relatively low temperature at a lower price than injection molding equipment. Has been. In order to increase mass productivity and improve manufacturing efficiency, a rotary compression molding machine (rotary movable compression molding machine) in which a large number of molding dies are attached to a rotating disk has been developed and adopted.

By the way, when the synthetic resin that is the raw material of the molded body is molded, the synthetic resin is once melted and kneaded at a high temperature. This molten resin has the property of reducing its volume when it is cooled after molding and the temperature is lowered. In the case of an injection molding method in which the product shape space (molding hole) being molded is fixed by a mold, the molten resin is replenished from the injection molding machine and the pressure is maintained as much as the volume of the molten resin is reduced.
On the other hand, in the compression molding method, a predetermined amount of molten resin cut (drop) is supplied to a female mold (cavity mold), and then a female mold and a male mold (such as a core mold) are used. Although compression molding is performed, the supply amount of the molten resin is determined from the beginning. In view of this, the molding slide portion (in the patent document 1, the cavity 43 described in paragraph [0049] is the driven mold 57) so as to reduce the volume of the molding hole of the molding die as much as the volume of the molten resin is reduced. And a small protrusion 46), and the molding sliding portion is moved to reduce the volume of the molding hole to reduce the pressure. (Patent Document 1, paragraphs [0045] to [0049], FIG. 5)

  In the case of such compression molding, a preform can be successively and continuously molded from a synthetic resin by a compression molding machine. It is possible to sequentially form into a container. At that time, the preforms molded by the compression molding machine can maintain a high temperature, and each preform can be continuously advanced to blow molding with almost no temperature variation. Not only can the bottle moldability be obtained, but it is also preferable from the viewpoint of maintaining the sterility of the filling system.

JP 2000-025729 A JP 2002-137282 A Japanese Patent No. 2867519 WO 2007/144312 International Publication Number WO 2009/034835 A1 International Publication Number WO 2008/114579 A1 International Publication Number WO 2006/040630 A2 JP 2002-321273 A

However, in compression molding, due to the structure of the molding sliding part, the sliding surface (molding sliding) that contacts the molten resin relatively early at the time of compression molding holding on the molding sliding part side or the other side of the sliding. Surface). Due to the early contact of the molten resin with the molding sliding surface, cooling and solidification of the molten resin in contact with the molding sliding surface begins, and the molten resin that contacts the molding sliding surface as the molding sliding portion moves is also included. Move or deform in a state of solidification. Therefore, if the resin is oriented, the part will cause resin orientation (residue defects such as wrinkles and streaks and residual strain due to orientation crystallization), resulting in poor appearance of the molded product. In some cases, the neck ring may be deformed during blow molding.
In addition, the above-mentioned patent document 2 discloses a compression molding method in which compression molding is performed with the aid of gas during molding of a molten resin. That is, Patent Document 2 discloses a compression molding apparatus that forms a hollow (double wall) by injecting high-pressure gas into a preform or a side wall or bottom of a container by a gas-assisted compression molding method. Although this method seems to be effective as a pressure retaining method for the resin orientation of a product having a hollow part, it cannot be used for a product having no hollow part. I had to take a pressure-holding method using a mold.
Further, as disclosed in Patent Document 3, by providing an air vent in the mold, it is possible to improve the exhaustability of air or gas accumulated in the molding hole and improve the fluidity of the molten resin to the preform nozzle side. ing.
Moreover, not only an air vent function but the structure which can send the compressed gas for making mold release easy at the time of mold release of a preform like patent document 4 is shown. 26th line, FIG. 11, 15).
In addition, as described above, the molten resin that is the raw material of the molded body has a property that the volume decreases as the temperature decreases. Therefore, since the temperature is lowered during molding of the molten resin, it is necessary to replenish the molten resin by the amount reduced in volume. In the case of the above-described injection molding, the molten resin is replenished by the injection molding machine for the amount of the molten resin reduced.
On the other hand, in the compression molding machine, a predetermined amount (drop) of the molten resin is supplied in advance to the cavity mold, and then compression molding is performed. Therefore, the supply amount of the molten resin is determined from the beginning. Therefore, the pressure is applied so as to reduce the volume of the molding part (molding hole) of the molding die as much as the volume of the molten resin is reduced. Therefore, the molding die of the compression molding machine is provided with a fitting sliding portion, and the volume of the molding hole is shrunk so as to shrink the fitting sliding portion (Patent Document 5).
The fitting sliding part of Patent Document 5 (corresponding to the sliding surface 23 of the mouth-and-neck mold (insert slide mold) 2 and the sliding surface 32 of the body mold (cavity mold) 3 of FIG. 1 of Patent Document 5) Is composed of a slide insert mold disposed above and a cavity mold disposed below the mold, and when the molds are closed together during compression molding, there is a fitting allowance (fitting gap). It is necessary to position it with high accuracy so that the center of the fitting sliding part which is small and also serves as a part of the molding hole is made to coincide. It was necessary to align the center of the sliding part between the slide insert mold and the cavity mold which were arranged at intervals in the vertical direction (Patent Document 6).
However, in order to align the centers of the respective molds while moving the molds in the above and below related positions up and down, it is necessary to accurately position each mold and operate the molds. In the process of closing the mold, it is necessary to take a mold structure that fits with the sliding part after the auxiliary positioning, which increases the manufacturing cost of the mold. . In addition, since the insert mold is divided into right and left parts, it has a high degree of freedom of operation that hinders positioning, and a mold structure or mechanism that can perform positioning each time a mold closing operation is performed from the mold open state. Had to be equipped with.
In addition, as a mold structure in which a sliding portion (molding sliding portion) for holding pressure is provided at a portion where the compression molding die is not separated vertically, a molding sliding portion on the preform bottom side as in Patent Documents 7 and 8 There is known a structure in which pressure is maintained from the bottom side. However, in the case of compression molding, unlike injection molding, holding pressure from the bottom of the preform facilitates the cooling and solidification of the resin on the lower side of the nozzle part during the holding pressure, so the holding pressure from the bottom side is Since it is blocked by the resin on the body part and the resin on the lower side of the nozzle part which has been cooled and solidified first, the holding pressure is difficult to be transmitted to the top surface side of the nozzle part, leading to sink of the nozzle part. In particular, in compression molding, in which molding is performed from a resin that is relatively cooler than injection molding to reduce acetaldehyde, cooling and solidification on the nozzle side is more likely to occur, making it more difficult to hold pressure from the preform bottom side to the top surface side. Become.
Furthermore, as disclosed in other embodiments of Patent Document 8 (paragraphs [0028] to [0032], FIGS. 6 to 8), two sets of sliding portions ((a) split mold members 226a and 226b are used. 2. Description of the Related Art A mold structure including a (slide insert mold) and a protruding portion 236 (; cavity mold) of a mold member 222, (b) split mold members 226a and 226b and split mold pieces 248a and 248b) is known. In this mold structure, the above-described sliding part (a) that is difficult to align is provided, and the support ring 12 (neck ring) is not evenly distributed around the entire circumference, but is slid from the direction deviated from the two side surfaces. A sliding portion (b) for holding the pressure is provided. About this sliding part (b), from the point which suppresses the distortion of the nozzle in the radial direction, from the radial direction of the neck ring is fixed without performing sliding for holding pressure from the biased direction, and from the vertical direction. It is desirable to perform sliding for holding pressure.
The present invention has been made in view of such circumstances, and a compression molding die that can omit or simplify the positioning structure between the slide insert die and the cavity die, or does not require positioning accuracy as compared with the prior art. The purpose is to provide a mold.

In order to achieve the above object, a compression molding mold of the present invention is a compression molding mold having a molding hole for compression molding a preform having a neck ring, and the side surface of the neck ring of the preform. A female die that forms the outer surface from the lower surface to the body and the bottom, a male die that forms the inner surface of the preform, and the outer surface of the nozzle portion side surface from the side surface or upper portion of the neck ring of the preform. The female mold, male mold and slide insert perform compression molding or release of the preform by relative advancement and retraction, and slide the compression molding mold during compression molding to maintain the molten resin. In the compression molding die having a molding sliding portion for pressing, the molding sliding portion is an upper peripheral portion of the molding hole of the female die or a lower portion of the molding hole of the slide insert die A sliding member disposed slidably up and down at least one edge, and the peripheral portion of the mold side were provided with the sliding member, consisting of,
The sliding member of the compression molding die is disposed on either the slide insert die or the female die, and is slid by being pressed from a die on the side where the sliding member is not disposed. Can move.
The sliding member of the compression mold is disposed at the upper peripheral edge of the female mold forming hole, and the neck ring is formed between the bottom of the slide insert mold and the upper part of the female mold. Forming the neck ring upper surface forming portion at the bottom of the slide insert mold, providing the neck ring lower surface forming portion at the upper edge of the molding hole of the female die, and forming the molding sliding surface and A side surface forming portion of the neck ring can be provided.

The compression molding die of the present invention is in the process of molding from a die (either a slide insert die or a female die) in which a sliding member is disposed during preform molding (when the die is opened and closed). Therefore, it is possible to simplify or omit the mechanism for positioning each time the mold is opened and closed, or to simplify the positioning accuracy.
The sliding member of the compression molding die is disposed on either the slide insert die or the female die, and is slid by being pressed from a die on the side where the sliding member is not disposed. Since it can be moved, the number of sliding members is reduced, which is simplified. Further, as in Patent Document 7 described above, it is not necessary to provide a separate mechanism for driving the sliding members, and the structure is simple. .
Since the compression molding die is not provided with a sliding member on the slide insert side, the sliding member does not need to be divided into (left and right) split molds in accordance with the slide insert, and has a simple structure.

1 is a schematic plan view of a compression molding system equipped with a compression mold according to an embodiment of the present invention. It is a schematic plan view of the compression molding apparatus of the compression molding system of FIG. 1 and the apparatus arrange | positioned in the periphery. It is a cut end view of the preform shape | molded by this embodiment. It is a cut end view in the closed state of the compression molding die by embodiment of the present invention. It is a cut end view in the open state of the compression molding die by embodiment of the present invention. It is a disassembled perspective view of the sliding member of this embodiment. FIG. 5 is a cut end view showing a state in which gas is supplied to the porous material of the sliding member in the compression molding die of FIG. 4 (the lower part in the figure is an enlarged view of the X part). A is a cut end view in a state where molten resin is supplied to the cavity mold, B is a cut end view in a state where the slide insert mold is closed and the core mold is lowered, and C is a neck ring formed by the molten resin. It is a cut end view just before reaching a part. D is a cut end view in a state where the molten resin reaches the upper end of the nozzle beyond the neck ring forming portion but does not reach the sliding surface of the neck ring, and E is a molding state during pressure holding of the compression mold. F is a cut end view showing a molded state after completion of pressure holding of the compression mold. 9A is an enlarged end view in the vicinity of the sliding member before pressure holding molding shown in FIG. 9E, and B is an enlarged cut end view in the vicinity of the sliding member at the time of pressure holding molding shown in FIG. 9F. FIG. 7 is a cut end view showing a porous ring mounted on a slide insert mold of a compression mold according to a modification of the present invention and its periphery. It is the cutting | disconnection end elevation which showed the example of air introduction using the groove | channel of the compression molding die by the modification of this invention, and looked at the division | segmentation surface of the slide insert die from the front. It is a cut end view which shows the example of air introduction using the annular slit of the compression molding die by the modification of this invention. 1 shows a compression mold according to a modification of the present invention (for footless cup molding, where the cup after molding is arranged upside down), and A is a cut end view immediately before compression molding of a molten resin. , B are cut end views during compression molding, C is a cut end view during holding pressure, and D is a cut end view in the Y-Y line direction of A. 1 shows a compression molding die (for foot cup molding) according to a modification of the present invention, wherein A is a cut end view immediately before compression molding of a molten resin, B is a cut end view during compression molding, and C is during pressure holding. It is a cut end view. It is a disassembled perspective view of the sliding member of the cavity metal mold | die of the compression molding metal mold | die by the 2nd Embodiment of this invention. FIG. 6 is a cut end view showing a third embodiment of the present invention, wherein the left side of the center line is a compressed state before holding the molten resin and the right side is a compressed state after holding.

Hereinafter, a preform compression mold according to an embodiment of the present invention will be described with reference to the drawings.
Although a cut end view is used to facilitate understanding of the mold structure and process, a depth line is described for the nozzle formation hole 36a of the slide insert mold 36 of FIG. 5 and FIG. The whole is displayed.
With reference to FIG.1 and FIG.2, the system example of the compression molding apparatus incorporating the compression molding die of this invention is shown. The resin supply apparatus 1 is provided with a cylindrical molten resin extruder 2 and a cutter wheel 8. The extruder 2 heat-melts and kneads a synthetic resin material such as polyethylene terephthalate, and conveys the molten resin to an internal gear pump in order to stably convey the molten resin. The gear pump is connected to an extrusion nozzle 4 provided with a downward nozzle (not shown) via a conduit, the extrusion nozzle 4 forms an extrusion opening at the lower end of the nozzle, and the molten resin is substantially cylindrical from the extrusion opening. It is formed into a shape and continuously extruded downward and supplied to the cutter wheel 8. The cutter wheel 8 is provided with a gripping member 9a (A in FIG. 8) for gripping the cut molten resin (drop) by the cutter provided in the rotating turret 9 and the cutter wheel. ing.

A compression molding device 31 and a blow molding machine 52 are disposed on the downstream side of the cutter wheel 8, and the compression molding device 31 includes a rotation support body 32 and a plurality of compression molds disposed on the rotation support body 32. A mold 33 is provided. In the case shown in FIG. 2, the rotary support 32 is driven to rotate in the counterclockwise direction opposite to the cutter wheel 8. A plurality of compression molding dies 33 are arranged at equal intervals in the circumferential direction of the rotary support 32 and move on a circular track.
The cutter wheel 8 is configured such that the tangent line of the rotating track of the molten resin gripping member and the rotating track of the cavity mold 34 (see FIG. 1) of the compression mold 33 are in the same direction, and the peripheral speeds thereof coincide with each other. . In the position or section of the rotation trajectory, the molten resin gripping member 9 a (A in FIG. 8) is rotated synchronously so as to be positioned immediately above the cavity mold 34. At this time, the molten resin is released from the gripping member 9 a and dropped into the cavity mold 34.

Next, the preform compression mold and the preform molded by this compression mold will be described in detail.
First, the preform 5 shown in FIG. 3 will be described.
As shown in the figure, the preform 5 includes a nozzle portion 5a, a body portion 5b, and a bottom portion 5c from the top to the bottom. The nozzle portion 5a includes an opening 5d that serves as an injection / pour-out port for beverages and the like when the container is molded, a male screw portion 5e into which a female screw of the cap is screwed, and an annular turnip portion that is disposed below the male screw portion 5e. 5f and a neck ring portion 5g. The body part 5b, which is a part to be blow-molded, is formed below the neck ring part 5g, and a bottom part 5c having an arc-shaped vertical section is provided below the body part 5b.

4 and 5 are end views of the above-described compression molding die 33. Hereinafter, the compression molding die 33 will be described in detail.
The compression mold 33 includes a cavity mold 34 that is a female mold, a core mold 35 that is a male mold, a slide insert mold 36 that is a split mold that is separated into right and left, and a cavity mold 34 that is supplied with molten resin. A guide ring 37 is provided around the outer periphery. In the open state of the compression mold 33 shown in FIG. 5, the core mold 35 is disposed on the upper side in the vertical direction, and the slide insert mold 36 is disposed below the support portion 35 a of the core mold 35. The cavity mold 34 is disposed below these parts.
The cavity mold 34 has a substantially cylindrical shape, and is formed with an annular convex portion 34b that protrudes upward toward the inside of the upper portion. A circular opening 34a is provided on the upper portion of the annular convex portion 34b. Forming hole 38 (note that forming hole 38 is formed as a forming hole 38 for convenience even when the shape changes when the compression mold 33 is opened and closed), and the inner peripheral surface of the forming hole 38 is An outer peripheral surface from the body part to the bottom part of the preform is formed. An annular positioning guide member 34c is provided on the outer peripheral side of the annular convex portion 34b with a space therebetween.

An annular sliding member 44 shown in FIG. 6 is disposed between the annular convex portion 34b and the lower portion of the positioning guide member 34c. The sliding member 44 is formed by a porous ring 44a serving as a gas introducing portion for supplying gas to the molding hole 38 and a main body 44e, and the porous ring 44a is attached to a stepped portion 44f formed at the inner end of the main body 44e. Is done. The material of the main body 44e of the sliding member 44 is not particularly limited as long as it is an alloy material for a mold, but in this embodiment, a preferable steel material SKD11 or wear-resistant copper alloy SAM214 (manufactured by Hitachi Metals) is used. ing.
Returning to FIG. 5, the sliding member 44 is disposed so as to be slidable in the vertical direction between the outer peripheral surface of the annular convex portion 34b and the lower portion of the positioning guide member 34c. The annular convex portion 34b and the sliding member 44 become a molding sliding portion for reducing the volume of the molding hole 38 and holding the pressure when the molten resin is compression molded as will be described later. In order to facilitate the arrangement of the sliding member 44, it is preferable that the sliding member 44 or the cavity mold 34 has a structure that can be appropriately disassembled and assembled.
An annular sliding floor 34d is provided between the annular protrusion 34b and the lower part of the positioning guide member 34c, and a plurality of spring accommodating chambers 34g (see FIG. 7) are provided in the sliding floor 34d at intervals in the circumferential direction. A coil spring 45 is disposed in each spring accommodating chamber 34g. In the compressed state, the coil spring 45 has an upper end connected to the lower surface of the sliding member 44 and a lower end connected to the bottom of the spring accommodating chamber 34g.

The core mold 35 is provided with a support portion 35a at the top, and a substantially cylindrical core body 35b extending downward from the center of the bottom surface is provided on the lower surface of the support portion 35a. The outer peripheral surface of the core body 35b forms the top surface or the inner peripheral surface of the preform. An annular recess 35c disposed concentrically with the core body 35b is formed on the lower surface of the support portion 35a so as to be recessed upward.
The slide insert mold 36 is divided into left and right parts and is a semicircular ring symmetrical with respect to the vertical plane. The slide insert mold 36 is formed with a nozzle forming hole 36a that vertically penetrates the center in a state where the split mold is assembled. The nozzle forming hole 36a forms an outer peripheral surface of a mouth portion (also referred to as a nozzle portion) 5a of the preform 5 (see FIG. 3), and forms a male screw 5e, a hook portion 5f, an upper surface side of the neck ring portion 5g, and the like. It becomes a forming part. As shown in FIG. 4, when the preform compression molding die 33 is clamped, a space substantially the same as the nozzle portion 5a shown in FIG. 3 is formed.
A semicircular arc-shaped protrusion 36b is formed on the upper portion of the slide insert mold 36, and becomes an annular protrusion in a state where the slide insert mold 36 is integrated with the left and right, and an annular recess 35c of the core mold 35 is formed. It is formed to fit.

Next, the cavity mold 34 and the slide insert mold 36 will be described in more detail.
The neck ring 5g (see FIG. 3) of the nozzle 5 is formed at the boundary between the cavity mold 34 and the slide insert mold 36. The lower part of the nozzle forming hole 36a is a neck ring 5g that spreads radially outward and downward. A neck ring upper forming portion 36c that forms the upper surface side is provided, and a neck ring lower forming portion 34f that forms the lower surface side of the neck ring 5g is provided on the upper end surface of the annular convex portion 34b.
The slide insert mold 36 is formed with a pressing portion 36d adjacent to the outer peripheral side of the neck ring upper forming portion 36c, and the pressing portion 36d is disposed at a position where the pressing portion 36d contacts the upper end surface 44b of the sliding member 44. The When these pressing portions 36d and the upper end surface 44b are in pressure contact, the inner peripheral surface of the sliding member 44 slides on the outer peripheral surface of the annular convex portion 34b. In this way, the gap between the neck ring upper forming portion 36c and the neck ring lower forming portion 34f is reduced by reducing the gap that was initially equal to or greater than the thickness of the neck ring 5g (the gaps S1, A and B in FIG. 10). S2), and is configured to substantially match the thickness of the neck ring 5g. A positioning protrusion 36e is formed around the pressing portion 36d of the slide insert mold 36 so as to protrude downward in an annular shape. The positioning protrusion 36e is fitted inside the positioning guide member 34c of the cavity mold 34.

  FIG. 7 shows the gas supply means arranged in the cavity mold 34. The sliding member 44 of the cavity mold 34 is provided with the above-described porous ring 44 a located on the inner peripheral surface of the upper end portion of the sliding member 44. The porous ring 44a is formed of a porous material. In the present embodiment, the porous ring 44a is formed of a metal sintered material such as stainless steel, and has a pore diameter of about 20 μm or less that communicates the surface and the inside in a mesh shape. Is formed innumerably. Examples of the sintered material include Pocerax II (Shinto Kogyo Co., Ltd .: Pocerax is a registered trademark), KuporeX (Kubota Co., Ltd .: registered trademark), Hiporas (Kobe Steel Works: registered trademark), and the like. It is done. The place where the porous ring 44a is disposed is preferably a preform forming surface in the vicinity of the sliding surface between the outer peripheral surface of the annular convex portion 34b and the inner peripheral surface of the sliding member 44, and more preferably, the pressure holding pressure In the process, the sliding member 44 may be disposed only in a region including the molded sliding surface 44a ′ (thick line portion) where the sliding member 44 contacts and slides with the annular protrusion 34b, or only in the region of the molded sliding surface 44a ′. . In other words, at the time of compression molding, the molding hole 38 is formed facing the molding hole during the initial stage of compression molding or during pressure holding, but is a portion that does not appear in the molding hole 38 or its periphery when pressure holding is completed.

  Specifically, in the present embodiment, the length between the neck ring upper forming portion 36 c and the neck ring lower forming portion 34 f is reduced, and the upper end portion of the annular convex portion 34 b is the inner portion of the sliding member 44. At least a portion that slides on the peripheral surface is formed. In the present embodiment, a step portion in which the porous ring 44a fits is formed at the upper inner peripheral end of the sliding member 44, and the porous ring 44a has no step (the upper end surface 44b or the inner peripheral surface of the sliding member 44 (groove). (Except 44c).

The gas supply means 48 for supplying gas to the porous ring 44 a has a supply nozzle 49 provided alongside the cavity mold 34, and the nozzle portion 49 a of the supply nozzle 49 passes through a through groove 37 b formed in the guide ring 37, and the tip portion thereof Arranged on the near side between the bottom of the sliding member 44 and the sliding floor 34d of the cavity mold 34 (in FIG. 7, the inner peripheral surface below the guide member 34c), gas can be supplied therebetween.
Normally, the sliding member 44 is disposed with airtightness between the annular convex portion 34b and the positioning guide member 34c, and has a hole for supplying gas from the sliding floor 34d side to the porous ring 44a. Provide. However, in the present embodiment, a plurality of grooves 44c are formed vertically in the circumferential direction of the inner peripheral surface of the sliding member 44 so that gas can be supplied from the sliding floor 34d to the porous ring 44a ( FIG. 6). The depth of the groove 44c may be as large as the gas passes. The gas supply means 48 is provided with a gas supply source (not shown), a pressure control valve, and the like, and an inert gas such as air, carbon dioxide, or nitrogen can be used as the gas to be ejected into the molding hole 38.

Returning to FIG. 5, the cylindrical guide ring 37 is disposed on the outer peripheral surface 34 e of the cavity mold 34, and can slide on the outer peripheral surface 34 e in the vertical direction. At the upper end portion of the guide ring 37, a tapered inner peripheral truncated cone surface 37 a is formed that expands radially outward in the upward direction. At the time of clamping the compression molding die 33, the outer peripheral truncated cone surface 36f is fitted after being slightly slid on the inner peripheral truncated cone surface 37a of the slide insert mold 36.
Although a detailed description is omitted, in the present embodiment, the compression molding die 33 is provided with a flow path such as a cooling device for cooling the nozzle portion 5a, the body portion 5b, and the bottom portion 5c of the preform 5 during compression molding. ing. Cooling water is supplied to the flow path from a cooling water supply source, and the flow rate and temperature of the cooling water can be adjusted. Although not described, in the present embodiment, the cavity mold 34, the core mold 35, and the slide insert mold 36 are each provided with a moving means that relatively moves up and down, and the slide insert mold 36 further includes this. Is equipped with a slide mechanism that opens and closes left and right

As shown in FIG. 1, a rotary preform take-out mechanism 50 (FIG. 1) is disposed downstream of the compression molding apparatus 31, and the preform 5 compression molded by the compression molding apparatus 31 is compression molded. It is taken out from the device 31 and transferred to a blow molding machine 52. The blow molding machine 52 forms a PET bottle by stretching the preform with high-pressure air. If necessary, the blow molding machine 52 is provided with heating equipment such as a heater.
A PET bottle take-out machine 53 is provided on the downstream side of the blow molding machine 52, and the PET bottle taken out from the blow molding machine 52 is transferred to the filling machine side.

Next, a preform molding procedure using the preform compression molding die 33 will be described.
Referring to FIG. 2 and FIG. 8A, the cavity mold 34 moves on a circular path by the rotary support 32. On the other hand, the gripping member 9 a that grips the molten resin 43 provided on the cutter wheel 8 rotates on a circular orbit separate from the cavity mold 34. 8A shows one of a plurality of compression molding dies 33 of the compression molding apparatus 31. FIG. In the initial state, the cavity mold 34, the slide insert mold 36, and the core mold 35 are arranged apart from each other in the vertical direction. The circular orbits of the gripping member 9a and the cavity mold 34 are configured to supply the molten resin 43 to the bottom of the molding hole 38 of the cavity mold 34 with one contact (tangent line) in common in the vertical direction.

When the molten resin 43 is supplied to the cavity mold 34, the gripping member 9 a moves away from the track of the cavity mold 34. Next, the slide insert mold 36 that has been opened to the left and right is moved toward the center of the core body 35b, and is closed into an annular shape as shown in FIG. 8B. When the core mold 35 is lowered to the closed slide insert mold 36, the slide insert mold 36 is integrated with the semicircular arc-shaped protrusion 36b fitted to the annular recess 35c at the top. Moreover, the core main body 35b will be in the state which penetrated the nozzle formation hole 36a.
As shown in FIG. 8C, when the core mold 35 is further lowered, the tip of the core body 35b enters the molding hole 38, and the slide insert mold 36 contacts the guide ring 37. That is, after the outer peripheral truncated cone surface 36f on the lower outer peripheral portion of the slide insert mold 36 is temporarily brought into contact with the inner peripheral truncated cone surface 37a on the upper inner peripheral surface of the guide ring 37, these surfaces are fitted to each other. The guide ring 37 and the slide insert mold 36 are in contact with each other in a centered state.

The core body 35b starts to compress the molten resin 43 by the lowering of the core mold 35 and flows from the side forming the preform bottom toward the side forming the body part, and by further lowering the core mold 35, The cavity mold 34 and the slide insert mold 36 are fitted by the positioning guide member 34c and the positioning projection 36e. The positioning guide member 34c and the positioning protrusion 36e are positioning members, and can further center the slide insert mold 36 (and the core mold 35) and the cavity mold 34.
In the present invention, the sliding member 44 is placed on a mold that is always slid during the preform compression molding operation (preform production) (in this embodiment, the annular convex portion 34b of the cavity mold 34). Since it is in a fitted state and there is no separation or connection by inserting / removing the molding sliding part each time the preform is compression-molded and the mold is taken out, the inner frusto-conical surface 37a and the outer frusto-conical surface 36f are fitted. When the centering of the cavity mold 34 and the slide insert mold 36 is sufficiently performed via the guide ring 37 by the centering of the guide link 37 and the slide insert mold 36, the positioning guide member 34c and the positioning guide member 37c are positioned. The fitting of the protrusion 36e can be set loosely or can be omitted. If there is no problem in the back-and-forth and left-right (horizontal) rattling of the moving means for moving the cavity mold 34, the core mold 35, and the slide insert mold 36 relative to each other, the guide ring 37 is provided. Can also be omitted. When the guide ring 37 is omitted, the outer peripheral inner surface of the annular recess 35c and the semicircular arc-shaped protrusion 36b are provided so that the left and right slide insert molds 36 can be clamped by contact pressing with the core mold 35. It is preferable that the outer peripheral surfaces of the circular truncated cone surfaces are brought into contact with each other in the same manner as the inner peripheral circular truncated cone surface 37a and the outer peripheral circular truncated cone surface 36f.

When compression molding is performed, a preform-shaped gap is formed by the cavity mold 34, the core mold 35, and the slide insert mold 36 as shown in FIG. 8C and FIG. Tries to fill the gap.
Specifically, as shown in FIG. 10A, the pressing portion 36d of the slide insert mold 36 is brought into pressure contact (contact) with the upper end surface 44b of the sliding member 44, whereby a preform-shaped gap is formed. The gap between the neck ring lower forming portion 34f and the neck ring upper forming portion 36c (hereinafter referred to as neck ring forming portions 34f and 36c) has a gap S1 larger than the thickness of the neck ring 5g of the actual preform 5. Yes.

Then, the molten resin is further compressed by the core mold 35, and the flow of the molten resin from the preform body side tends to branch to the neck ring side and the nozzle side, but as shown in FIG. Before the molten resin enters the neck ring lower forming portion 34f (neck ring forming portions 34f, 36c), a gas is supplied to the porous ring 44a by the air supply means 48, and a gap between the neck ring forming portions 34f, 36c. Gas is ejected and pressed into S1. Therefore, as shown to D of FIG. 9, when the molten resin 43 passes the neck ring formation parts 34f and 36c, the contact to the sliding surface 44d is suppressed.
It is preferable that the pressure of the gas jet is adjusted so that the molten resin is not in contact with the sliding surface 44d of the porous ring 44a before the molten resin during compression fills the molding hole 38. That is, it is preferable to adjust the pressure so that the molten resin that has been compressed and flowed finally reaches the sliding surface 44d and fills the molding hole 38.

As shown in FIG. 9E, immediately after the inside of the molding hole 38 is filled with the molten resin, the core mold 35 is slightly above the lowermost position (the state shown in FIG. 10A). Since the slide insert mold 36, the core mold 35, and the cavity mold 34 are cooled by circulation of cooling water, the molten resin 43 is cooled during mold clamping, and the molten resin contracts.
In accordance with the shrinkage of the molten resin, the core mold 35 is further lowered to hold the pressure. That is, when the core mold 35 is lowered, the pressing portion 36 d presses the sliding member 44 downward against the urging force of the coil spring 45. As the core mold 35 is lowered, the gap S2 between the neck ring forming portions 34f and 36c is narrowed as shown in FIG. 10B. At this time, the inner surface of the sliding member 44 and the molding sliding surface 44a ′ (FIG. 7, enlarged view of the X portion) of the porous ring 44a slide with the outer surface of the annular convex portion 34b.

When the gas is not ejected from the porous ring 44a, the molten resin enters the gap S2 between the neck ring forming portions 34f and 36c at an early stage, the molten resin comes into contact with the inner surface of the porous ring 44a, and then the annular convex portion When 34b relatively rises on the inner surface of the porous ring 44a, the molten resin rises greatly while contacting the inner surface of the porous ring 44a. In this way, when the molten resin is in contact with the part that is moving greatly, if the molten resin is of an oriented nature such as PET, excessive resin orientation occurs, resulting in poor appearance of the preform, At the time of blow molding, the neck ring may be deformed.

In the present embodiment, since the gas is ejected from the sliding surface 44d of the porous ring 44a by the gas ejection means 48, the contact between the inner surface and the molten resin can be suppressed. The gas passes through the gap of the groove 44c, spreads from the upper end of the groove 44c to the entire mesh-like passage of the porous ring 44a, and jets the gas to the entire periphery of the gap S2 between the neck ring forming portions 34f and 36c (X in FIG. 7). By referring to the enlarged view of the part, the molten resin is prevented from contacting the sliding surface 44d of the porous ring 44a at the beginning of compression molding. At the time of holding pressure, preferably, when the core mold 35 reaches the lowermost position, the sliding between the porous ring 44a and the annular protrusion 34b is finished, and the gap S2 becomes the neck ring 5b of the preform 5. When the gas pressure adjustment, gas ejection ON / OFF, and pressure release are set so that the molten resin reaches the sliding surface 44d at the same interval, the molded sliding surface 44a 'of the porous ring 44a Since the neck ring molding surface of the molding hole 38 is not formed, the contact between the molten resin and the molding sliding surface 44a ′ can be avoided.
As the timing of the gas ejection start with reference to FIG. 8, for example, immediately after the cavity hole 34, the core mold 35, and the slide insert mold 36 are combined to form the molding hole 38 (FIG. 8C). However, it is more preferable that the resin reaches the neck ring portion (slightly after FIG. 8C). The timing of gas ejection may be a timer or the like, but when the molding hole 38 is formed or immediately after the position of the female mold, the position of the male mold, or the relative positional relationship between the male mold and the female mold. It is preferable to set so as to eject gas.
Thus, the resin orientation of the molten resin can be prevented, and a high-quality preform can be molded.

Also, conventionally, one of the sliding parts is provided in the slide insert mold, the other of the sliding parts is provided in the cavity mold and each is used as a fitting sliding part, and the sliding parts are moved while moving these molds up and down. Since the moving part is fitted (separated / coupled), the guide ring 37 for positioning the slide insert mold and the cavity mold, the positioning guide member 34c, and the positioning projection 36e are provided with high accuracy. For example, it was necessary to devise and consider the fitting sliding part that forms part of the molding hole so that it can be fitted very accurately each time molding (mold separation / bonding) in a tight fitting allowance. .
In this embodiment, since the sliding member 44 is provided on the annular convex portion 34 of the cavity mold 34 to form a molding sliding portion, the sliding portion always comes into contact with the cavity mold 34, and the sliding portion (molding) No need to worry about fitting the sliding part). Therefore, the manufacturing cost of the compression mold 33 can be reduced.
In addition, since the molding sliding portion is provided in the vicinity of the location where the neck ring 5g is formed, the resin accumulated in the portion forming the neck ring portion can be retained and replenished to the nearby nozzle side during the retention. Therefore, sink marks of the nozzle can be suppressed and pressure can be effectively retained.
Furthermore, since pressure holding is performed by sliding in the vertical direction without applying a load deviating from the radial direction of the neck ring, distortion in the radial direction of the nozzle and the neck ring is suppressed.

When the inner surface of the porous ring 44a is shielded from the molding hole 38 when the gap S2 is formed, the gas is not stopped from being supplied from the supply nozzle 49, and the gas is continuously supplied to the nozzle portion 49a. You may continue to supply. Since the sliding surface 44d is closed, the ejection of gas into the forming hole 38 is automatically stopped. Further, in the case where the sliding surface 44d is exposed in the molding hole 38 at the final time of compression molding, gas ejection from the supply nozzle 49 can be separately provided in view of the timing when the sliding is completed. It is recommended to stop or release the pressure by controlling the valve.
Specifically, the timing immediately before the end of the compression molding (FIG. 9E, F: enlarged views J, K in this embodiment) is suitable as the timing of the end of the gas ejection or the timing of releasing the pressure at the end of the gas ejection. In addition to the timer, the timing of releasing the pressure at the end of the gas ejection or at the end of the gas ejection is the same as the time of the gas ejection, the position of the female mold, the male mold position, or the male mold and the female mold. It is preferable to calculate and set from the relative positional relationship.
Even if the gas ejection is stopped or the pressure is released, the pores of the porous ring 44a are fine, so that the molten resin does not enter or clog.
When the compression molding is completed, the core mold 35 and the slide insert mold 36 move upward, and the mold release from the cavity mold 34 is performed. Next, the core body 35 b is pulled out from the preform 5. The preform 5 is removed from the slide insert mold 36 by opening the slide insert mold 36 to the left and right.

As shown in FIG. 1, on the downstream side in the rotation direction of the compression molding apparatus 31, a take-out mechanism 50 for taking out the preform 5 molded from the cavity mold 34 is disposed and removed from the slide insert mold 36. The preform 5 is rotated and conveyed by the take-out mechanism 50 to the blow molding machine on the downstream side.
By the way, the temperature of the nozzle portion 5a is preferably lower from the viewpoint of preventing deformation of the nozzle portion 5a of the preform 5 when taking out the preform after completion of compression molding or sealing compressed air (nozzle seal) in blow molding. On the other hand, in order to perform blow molding, when the temperature of the body portion 5b is low, it is necessary to apply heat with an infrared heater such as near infrared, hot air, or width radiation heat. Therefore, the preform 5 is heated by the infrared heater or the like when the temperature is low during the conveyance of the preform in the take-out mechanism 50.

Since the preforms that have been compression-molded from the compression-molding mold 33 are successively taken out and put into the blow-molding machine 52, if the molding speed of the blow-molding machine 52 is equal to or higher than the molding speed of the compression-molding mold 33 The preform that has been compression molded does not have a waiting time until blow molding, and can be blow molded immediately. The preform 5 conveyed from the take-out mechanism 50 to the blow molding machine is set in a blow molding die, injected with high-pressure air, and stretched in the vertical and horizontal directions to be molded into a container. The compression molding device 31, the take-out mechanism 50, and the blow molding machine 52 are mechanically connected by gears or the like, or are electrically synchronized by a servo motor, so that the compression molded preform has a constant time until blow molding. In this case, variations in individual preform temperatures immediately before blow molding can be suppressed, so that stable blow molding is possible.
In the present embodiment, the sliding portion that temporarily forms the molding hole of the compression molding die during holding pressure, or the vicinity of the sliding portion, gas is jetted to contact the molten resin mold sliding portion. Can be prevented, and significant resin orientation can be prevented. Therefore, a quality bottle can be formed by subsequent blow molding.

FIG. 11 shows an example in which the location of the porous ring is changed.
In the above embodiment, as shown in FIG. 7, the porous ring 44a is attached to the sliding member 44, and the groove 44c is formed on the inner peripheral surface of the sliding member 44 to supply gas to the porous ring 44a. 11, the porous ring 36g is attached to the neck ring forming portion of the slide insert mold 36, and the sliding member 44 has a porous ring 36g inside the sliding member 44 instead of the groove 44c. It is also possible to form a vent hole 44c ′ through which a gas extending to the bottom of the gas flows and supply the gas to the porous ring 36g.
The porous ring 44a is divided into two parts (or more than two parts) in the same manner as the insert slide mold 36, and together with the porous space 44a. Further, it is possible to form a vent hole in the insert slide mold 36 and to circulate gas from the insert slide mold 36 side.
Even if comprised in this way, the effect similar to the said embodiment can be acquired, and also the improvement in a design layout can be aimed at.

FIG. 12 shows a modification of the gas introduction part.
In the above embodiment, the porous ring 44a is disposed on the sliding member 44 and gas is introduced. However, in this modification, the porous ring 44a is not used, and FIG. It is the end elevation which looked at the division surface of this.
As shown in FIG. 12, a groove 67 having a depth of about 20 .mu.m is formed in a gas introduction portion at a portion facing (communicating with) the formation portion of the neck ring 5g (see FIG. 3) of the preform 5 on the split surface of the slide insert mold 36. It is formed as. The groove 67 communicates with the gas supply hole 68, and the gas supply hole 68 is connected to the gas supply device 69 through a pipe line penetrating the inside of the slide insert mold 36. The groove 67 may be used as a gas introduction part, and gas may be press-fitted from the slit-shaped groove 67 having a thickness of about 20 μm formed when the slide insert mold 36 divided in the front and rear is coupled. The injection of the molten resin into the formation part of the neck ring 5g can be delayed by the gas injection.
Further, as shown in FIG. 12, an air vent 70 is formed to flow gas on the nozzle top surface side of the preform 5 to prevent the molten resin from entering. The air vent 70 communicates with the gas suction hole 71 and passes through the air vent 7. The gas suction device 72 may be connected. With respect to the air vent 70 on the nozzle top surface side, gas is sucked so as to promote the flow of resin toward the nozzle portion 5a (FIG. 3).

FIG. 13 shows another modification of the gas introduction part.
In this modification, the porous ring 44a of the sliding member 44 in FIG. 7 is eliminated, and the clearance (gap) c for fitting between the sliding member 44 and the annular convex portion 34b is about 20 μm as shown in FIG. The gas may be introduced by forming an annular slit s facing the sliding surface 44d. The introduction of gas is supplied from a groove 44 c formed in the sliding member 44.
Furthermore, in the above embodiment, the molding object of the compression molding die is a preform, but it is formed by a normal male die 61 and a female die 62 that do not require blow molding as shown in FIG. 14 or FIG. The present invention can also be applied to products by compression molding such as the cup 63.
That is, in FIG. 14, a porous ring 64 is disposed on the male mold 61, and gas is supplied to the sliding surface 62 a of the female mold 62 that forms the flange 63 a of the cup 63. In FIG. 15, a porous ring 64 is provided in the female mold 62, and the porous ring 64 cooperates with the sliding member 65 to form a foot 63 b of the cup 63, and slides with the sliding member 65. A moving surface 64a is provided.
In this case, a cup 63 having a flange 63a at the upper end as shown in FIG. 14 may be used. However, as shown in FIG. 15, for example, with a footed cup 63, the resin flows in two directions in the direction of the foot 63b and the trunk 63c. The one that branches in (or multi-directional) can suppress the flow of resin to the molding sliding surface 64a side, suppress the inflow of molten resin to the molding sliding surface 64a side in the early stage of molding, This is more effective in suppressing resin orientation.
Note that reference numeral 66 in FIGS. 14 and 15 is a gas introduction hole into the porous ring 64.

FIG. 16 is a second embodiment of the present invention.
In the present embodiment, since only the sliding member is different from the first embodiment, the other portions will be described with the reference numerals used in the first embodiment.
In the first embodiment, the sliding member 44 includes the gas ejection ring 44a, and the gas is ejected from the gas ejection ring 44a, thereby preventing the resin orientation of the molten resin on the molding sliding surface during compression molding. Was the preferred form. However, when the resin orientation such as the neck ring of the preform is not a problem, the gas introduction part (porous ring 44a, groove 44c) and the gas supply means 48 as shown in FIG. do not need.
Therefore, not only the neck ring of the preform, but also a molded product in which such resin orientation is not particularly problematic, it is not necessary to eject gas, so that no gas introduction part or gas supply means is required.
In the present embodiment, as shown in FIG. 16, the inner surface of the main body 54a of the sliding member 54 forms an inner peripheral surface 54b having no steps or grooves, and a cylindrical member 54c is disposed on the inner peripheral surface. The main body 54a and the cylindrical member 54c are formed of different materials, and the cylindrical member 54c is formed of a material having a small friction coefficient and strong against wear.
Thus, by using different materials for the main body 54a and the cylindrical member 54c, it is possible to reduce the material cost of the cavity mold by making only the portion of the cylindrical member 54c an expensive material.
In this embodiment, the main body 54a and the cylindrical member 54c of the sliding member 54 are formed by separate members (two members), but may be formed by a single member by integral molding.
The material of the main body 54a of the sliding member 54 is not particularly limited as long as it is an alloy material for a mold, as in the first embodiment, but a preferable steel material SKD11 or wear-resistant copper alloy SAM214 (Hitachi Metals). Use).

FIG. 17 shows a third embodiment of the present invention.
In addition, in this embodiment, since only the arrangement | positioning location of a sliding member differs with respect to the said 1st Embodiment, about the same name part, the code | symbol used in 1st Embodiment is attached | subjected and demonstrated.
In the above embodiment, the sliding member 44 is provided in the cavity mold 34, but a sliding portion may be provided on the slide insert mold 36 side as shown in FIG. Note that the left side of the center line of the compression mold in FIG. 17 is a cut end view showing the compressed state before holding the molten resin, and the right side showing the compressed state during holding.
The sliding member 44 is accommodated in the lower peripheral edge of the molding hole (in this embodiment, the forming portion of the nozzle 5a outer surface or the neck ring 5g upper surface of the preform 5 in FIG. 3) of the slide insert die 36 of the compression molding die 33. A hole 36g is formed, the sliding member 44 is slidably disposed in the accommodation hole 36g in the vertical direction, and a coil spring 45 is disposed between the upper surface of the accommodation hole 36g and the upper surface of the sliding member 44, The sliding member 44 is urged downward. A stopper ring 60 that functions as a stopper and a stopper for the sliding member 44 is attached to the lower side of the accommodation hole 36g. When the slide insert mold 36 is lowered or the cavity mold 34 is raised, the sliding member 44 is pressed by the cavity mold 34 without the sliding member, thereby sliding upward in the accommodation hole 36g.

However, since the slide insert mold 36 is a half mold, it is somewhat difficult to manufacture the slide member 44. Therefore, it is preferable to provide the slide insert mold 36 on the cavity mold 34 side as in the first and second embodiments. In FIG. 17, the guide ring 37, the positioning guide member 34c and the positioning protrusion 36e shown in FIG. 4 and the like are not employed, and the sliding member 44 is made of one kind of material.
The mold that forms the outer peripheral side surface of the neck ring 5g may be the sliding member 44 as in the first embodiment (FIG. 10) or the cavity mold 34 as shown in FIG. Although not shown, the outer peripheral side surface of the neck ring 5g may be formed by the slide insert mold 36, or the outer peripheral side surface of the neck ring 5g is combined with the slide insert mold 36 or the cavity mold 34. It may be formed.

As mentioned above, although this invention was demonstrated in detail, referring an accompanying drawing based on embodiment, this invention is not limited to the said embodiment and modification, Furthermore, it does not deviate from the scope of the present invention. Other variations or modifications are possible.
In the above embodiment, the cavity mold 34, and in the modification shown in FIG. 12, the slide insert mold 36 is provided with the gas introduction part. For example, as in Patent Document 4, the core mold is provided with the sliding surface. In the case of a mold, a gas introduction part may be provided in the core mold to control the timing of gas introduction. Moreover, it is applicable to the metal mold | die provided with the sliding surface in a separate metal mold | die like patent document 1, respectively. In the embodiments described so far, the gas introduction part is provided in each mold, but a plurality of molds may be provided.
Even if comprised in this way, the effect similar to the said embodiment can be acquired, and also the improvement in a design layout can be aimed at.
Further, in the above embodiment, the sliding member 44 is slid by the coil spring 45 at the time of holding pressure, and holding pressure at the time of compression molding is performed. Instead of the coil spring 45, an elastic member such as rubber, an air spring, or a pneumatic cylinder is used. Other sliding means such as a mechanism such as a hydraulic cylinder and a motor can be used.
The sliding member 44 may be provided on both sides of the slide insert mold 36 and the cavity mold 34. However, it is preferable to provide the slide member 44 on either one of the slide insert mold 36 and the cavity mold 34, as described above. It is more preferable to provide it on the cavity mold 34 side because of the difficulty in manufacturing.

5 Preform 5g Neck ring 31 Compression molding device 33 Compression molding die 34 Cavity die 34b Annular convex portion 34f Neck ring lower forming portion 35 Core die 35b Core body 36 Slide insert die 36c Neck ring upper forming portion 36d Pressing portion 44 Sliding members 36g, 44a Porous ring (porous material)
44b Upper end surface 44c Groove 44c 'Vent hole 44d Sliding surface 45 Coil spring 48 Air supply means 49 Supply nozzle 54 Sliding member 61 Male mold 62 Female mold 67 Groove 70 Air vent

Claims (3)

A compression mold having a molding hole for compression molding a preform having a neck ring,
A female mold that forms an outer surface from the neck ring side surface to the bottom surface of the preform to the body portion and the bottom portion;
A male mold that forms the inner surface of the preform;
From the side or top of the neck ring of the preform, a slide insert mold that forms the outer surface of the nozzle side surface,
The female mold, male mold and slide insert perform compression molding or release of the preform by relative advancement and retraction,
In the compression molding die provided with a molding sliding part for sliding the compression molding die during compression molding to hold the molten resin,
A sliding member disposed so that the molding sliding portion is slidable vertically on at least one of the upper peripheral edge of the molding hole of the female mold or the lower peripheral edge of the molding hole of the slide insert mold; A compression mold having a peripheral portion on the mold side on which the sliding member is disposed.   The sliding member is disposed on either the slide insert mold or the female mold, and slides by being pressed from a mold on the side where the sliding member is not disposed. The compression molding die according to claim 1. The sliding member is disposed on the upper peripheral edge of the molding hole of the female mold,
Forming a molded portion of the neck ring between the bottom of the slide insert mold and the top of the female mold;
Provide the neck ring upper surface forming portion at the bottom of the slide insert mold,
A neck ring lower surface forming portion is provided at the upper edge of the molding hole of the female die,
The compression molding die according to claim 1 or 2, wherein the sliding member is provided with a molding sliding surface and a side surface forming portion of a neck ring.

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