JP4060457B2 - Compression molding equipment for synthetic resin articles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for compression molding a synthetic resin container lid applied to a synthetic resin article, preferably a container for containing a beverage or the like.
[0002]
[Prior art]
As a typical example of a synthetic resin container lid applied to a container for containing a synthetic resin article, for example, a beverage, etc., a top wall and a skirt wall hanging from the periphery of the top wall are provided. Examples of the inner peripheral surface include a form in which an internal thread that can be engaged with an external thread formed in the opening of the container is formed. Such a synthetic resin container lid is generally integrally formed by compression molding. As a typical example of a compression molding apparatus for compressing and molding a synthetic resin container lid, an upper mold assembly and a lower mold assembly that cooperate with each other, and an upper mold assembly and a lower mold assembly are mutually connected. A mold opening / closing means for relatively moving so as to approach and separate from each other and an elastic means disposed in the upper mold assembly are provided. When the upper mold assembly and the lower mold assembly are brought close to each other by the mold opening / closing means, a molding space is formed between them, and the synthetic resin material supplied in advance to the molding space is compression-molded in the molding space. Then, a synthetic resin container lid is formed. The elastic means defines the molding pressure during compression molding.
[0003]
The mold opening / closing means comprises a combination of a cam and a cam follower, and these combinations are arranged in association with each of the upper mold assembly and the lower mold assembly. The upper mold assembly includes a cylindrical case that is a stationary frame having a vertical hole. A stripper is coupled to the lower end of the case via an elastic body made of plate-like polyurethane. The elastic body and the stripper are each formed with a vertical hole having a common axis with the vertical hole of the case. A core assembly is inserted in the longitudinal holes of the case, the elastic body and the stripper so as to be movable in the axial direction. The core assembly includes a rod body having a cam follower at the upper end and a plurality of disc springs that constitute elastic means for the rod body, and a pressing member is coupled by an initial load setting bolt. The initial load is set by deflecting the entire disc spring by a predetermined amount with the initial load setting bolt. A male assembly whose lower end portion forms a male mold is coupled to the pressing member. The core assembly configured as described above is moved up and down in the vertical hole by the cooperation of the cam and the cam follower, is lowered during molding, and protrudes downward by a predetermined amount from the lower surface of the stripper. The lower mold assembly includes a columnar support having a cam follower at the lower end, and a female mold assembly screwed to the upper end of the support. A female die (cavity) is disposed at the upper end of the female die assembly.
[0004]
The upper mold assembly and the lower mold assembly are separated from each other by the mold opening / closing means when not molded, but when molded, the lower mold assembly faces the upper mold assembly with respect to the upper mold assembly. The upper surface of the female assembly is brought into pressure contact with the lower surface of the stripper. Next, the core assembly is lowered by the mold opening / closing means so that the male mold protrudes from the lower surface of the stripper into the female mold, thereby forming a molding space between the female mold and a part of the lower surface of the stripper and the male mold. The synthetic resin material supplied in advance is compression-molded in the molding space, and a synthetic resin container lid having a predetermined shape is molded. When molding the synthetic resin container lid, the disc spring is further deflected by a predetermined amount from the initial load setting position, and a predetermined molding pressure is obtained. A synthetic resin container lid is molded in the molding space, and after the cooling process is completed, the lower mold assembly is lowered by the mold opening / closing means and separated from the upper mold assembly. The female mold is separated from the lower surface of the stripper and released from the synthetic resin container lid. Next, the core assembly is raised by the mold opening / closing means, and the male mold is moved above the lower surface of the stripper in the vertical hole of the case. As a result, the male mold is forcibly removed from the synthetic resin container lid and released. The synthetic resin container lid is stripped by the lower surface of the stripper and then freely dropped from the lower surface of the stripper. A plurality of mold means comprising the upper mold assembly and the lower mold assembly are disposed on the rotary support at intervals in the circumferential direction, and each mold means is made of synthetic resin by rotation of the rotary support. Each time the material supply area, the molding area, the cooling area, and the molded product discharge area are rotated once, one synthetic resin container lid is formed.
[0005]
[Problems to be solved by the invention]
In the compression molding apparatus, the synthetic resin container lid is molded in the molding space, and after the cooling process is finished, the female mold is separated from the lower surface of the stripper and released from the synthetic resin container lid, and then the core assembly As a result of the ascent, the male mold is moved above the lower surface of the stripper in the vertical hole. As a result, the male mold is forcibly removed from the synthetic resin container lid and released. The synthetic resin container lid is stripped by the lower surface of the stripper and then separated from the lower surface of the stripper by free fall. In general, the vertical holes in the lower ends of the male mold assembly and the upper mold assembly have air vent holes (so that a vacuum is not generated between the core assembly and the molded synthetic resin container lid). A gap) is formed. However, if these air vent holes are blocked by dust such as synthetic resin debris due to the use of the device, the air flow becomes worse and the above-mentioned vacuum is generated due to the rise of the core assembly, and the synthetic resin container lid becomes a stripper. In some cases, it will be adsorbed to the lower surface of the plate and not fall freely. When the synthetic resin container lid is moved to the molded product discharge area while being adsorbed to the lower surface of the stripper, it is forcibly dropped by the air ejected from the air nozzle provided in the molded product discharge area. However, if it never falls, it will collide with the guide for the molded product discharge provided in the molded product discharge area and be dropped. However, the synthetic resin container lid that has been dropped in this manner has a strong tendency to be damaged or deformed, which causes defective products.
[0006]
The present invention has been made based on the above facts, and an object of the present invention is to provide a novel synthetic resin article compression molding apparatus capable of smoothly and reliably dropping the molded synthetic resin article from the lower surface of the stripper. It is to be.
[0007]
Another object of the present invention is to provide a novel synthetic resin article compression molding apparatus capable of preventing damage and deformation of a molded synthetic resin article.
[0008]
Still another object of the present invention is to provide a novel synthetic resin article compression molding apparatus capable of reducing the occurrence of defective products.
[0009]
Other objects and features of the present invention will become apparent from the following description of embodiments of a compression molding apparatus for synthetic resin articles constructed according to the present invention in detail with reference to the accompanying drawings.
[0010]
[Means for Solving the Problems]
According to the present invention,
An upper mold assembly and a lower mold assembly that cooperate with each other, and a mold opening / closing means that moves the upper mold assembly and the lower mold assembly relative to each other so as to approach and separate from each other. The assembly includes a stripper having a vertical hole, and a core assembly that is disposed so as to be moved up and down in the vertical hole of the stripper by the mold opening / closing means and has a lower end portion constituting a male mold. The mold assembly includes a female mold, and when the upper mold assembly and the lower mold assembly are brought close to each other by the mold opening and closing means, the upper surface of the female mold and the lower surface of the stripper are pressed against each other, The core assembly is lowered so that the male mold protrudes from the lower surface of the stripper into the female mold, thereby forming a portion between the female mold, a part of the lower surface of the stripper, and the male mold. Space is formed and the synthetic resin material supplied is compression molded in the molding space In the compression molding apparatus for a synthetic resin article to be tightened, the stripper is provided with at least two knockouts at intervals in the circumferential direction, and each of the knockouts has a lower surface that is a predetermined amount from the lower surface of the stripper. The working position is provided by a spring member disposed between the stripper so as to be movable between a working position to be projected and a non-working position in which each lower surface is aligned with the lower surface of the stripper. The upper die assembly and the lower die assembly are brought close to each other by the die opening / closing means so that the upper surface of the female die and the lower surface of the stripper are pressed against each other. And each of the knockouts is moved from the operating position against the corresponding spring member and positioned in the non-operating position.And
The stripper includes a cylindrical portion including the vertical hole and the lower surface, and the cylindrical portion has a predetermined depth position extending in the axial direction from the lower surface with a predetermined circumferential width at a symmetrical position across the axis. A pair of mounting grooves having a bottom surface existing on the stripper, and a stripper having a large diameter hole extending in the axial direction from each bottom surface of the mounting groove, and an axial direction extending from the bottom surface of each large diameter hole. A long hole extending in the axial direction is perpendicular to the axis, and one end is opened on the outer peripheral surface of the cylindrical portion, and the other end is the vertical hole. Each of the knockouts is fitted to the corresponding mounting groove so as to be movable in the axial direction and detachable, and the inner peripheral surface of the vertical hole of the stripper. And a main body having a part of the lower surface of the stripper and the main body A rod portion projecting in the axial direction and fitted to the corresponding large-diameter hole so as to be movable in the axial direction and detachable, and to both ends of the rod portion perpendicular to the axis of the rod portion And a stopper pin that is movably fitted in the corresponding long hole, and the main body portion is fitted in the corresponding mounting groove. The rod portion is fitted to the stripper by being fitted into the large-diameter hole to which the rod portion corresponds, and the long holes to which the both ends of the stopper pin correspond to each of the small-diameter holes of the stripper. The spring members are inserted, and each of the spring members acts on the rod portion of the corresponding knockout to constantly bias the knockout, and the working position of each of the knockouts is determined by each of the stopper pins. Of the corresponding slot Is defined by contact with the end,
A compression molding apparatus for a synthetic resin article is provided.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Preferred embodiments of a compression molding apparatus for synthetic resin articles constructed according to the present invention will be described below in more detail with reference to the accompanying drawings. In FIG. 1 to FIG. 9, substantially the same parts are denoted by the same reference numerals. The synthetic resin article compression-molded by the compression molding apparatus according to the present invention is not limited thereto, but in the illustrated embodiment, it is a synthetic resin container lid.
[0013]
Referring to FIG. 1, the compression molding apparatus generally indicated by reference numeral 2 is driven to rotate by a drive source which may be an electric motor at a predetermined speed in the counterclockwise direction of FIG. 1 about a shaft 4 extending substantially vertically. A rotary support 6, a synthetic resin material supply means 7, and a molded product carry-out means 8 are provided. A plurality of mold means 10 are mounted on the rotary support 6 at equal intervals in the circumferential direction. As will be described later in detail, each of the mold means 10 is composed of an upper mold assembly 12 and a lower mold assembly 14, and is moved through a circular conveyance path along with the rotation of the rotary support 6. In between, it is opened and closed as required by the mold opening and closing means.
[0014]
When the mold means 10 is in the synthetic resin material supply area indicated by the symbol A, the synthetic resin material is supplied from the synthetic resin material supply means 7 into the mold means 10 in the open state. The synthetic resin material supply means 7 includes an extruder 7a, a conduit means 7b, and a die head 7c. The heated and melted synthetic resin material extruded from the extruder 7a is supplied to the die head 7c through the conduit means 7b, and the die head 7c. It is extruded through an extrusion opening (not shown) provided in A cutting means (not shown) is provided in association with the extrusion opening of the die head 7c. The synthetic resin material extruded through the extrusion opening is cut by the cutting means and supplied to the mold means 10 in the synthetic resin material supply area A. The Next, the mold means 10 is closed while the mold means 10 passes through the molding region indicated by the symbol B, and the synthetic resin material is compression molded into a synthetic resin container lid which is a molded product of a required shape. While the mold means 10 passes through the cooling area indicated by the symbol C, the mold means 10 is maintained in a closed state, and the compression-molded synthetic resin container lid is cooled. The mold means 10 is opened while moving from the downstream end of the cooling zone C toward the molded product discharge area indicated by D, and the synthetic resin container lid is discharged in the molded product discharge area D. In the molded product discharge area D, molded product discharge means 8 is arranged. The molded product unloading means 8 includes an air injection pipe 8a extending along the radially inner side of the moving path of the molded synthetic resin container lid, and an unloading chute 8b disposed below the moving path. . When the mold means 10 is opened in the molded product discharge area D, the synthetic resin container lid is unloaded by the air injected from the air injection pipe 8a of the molded product discharge means 8 at the same time as being freely dropped from the mold means 10. Forcibly moved to the chute 8b and carried out through the carry-out chute 8b. The synthetic resin material supply means 7 and the molded product carry-out means 8 themselves may have a well-known configuration, and thus detailed description thereof is omitted.
[0015]
Since each of the mold means 10 mounted on the rotary support 6 has substantially the same configuration, the configuration of one of the mold means 10 will be described below. Referring to FIG. 2, the mold means 10 includes an upper mold assembly 12 and a lower mold assembly 14 that cooperate with each other. The upper die assembly 12 includes a cylindrical case 18 that is a stationary frame having a vertical hole 16. The case 18 is coupled to the rotary support 6. A stripper 22 is coupled to the lower end of the case 18 via an elastic body 20 made of plate-like polyurethane. A flange 24 is integrally provided at the lower end of the case 18, and a flange 26 is integrally provided at the upper end of the stripper 22. The elastic body 20 is interposed between the flange 24 and the flange 26, and the flange 24 and the flange 26 are fastened by the bolt 28 via the elastic body 20, whereby the stripper 22 is coupled to the lower end of the case 18. The stripper 22 is movable relative to the bolt 28 (non-threaded portion thereof). The elastic body 20 and the stripper 22 are formed with vertical holes 20a and 22a having a common axis with the vertical hole 16 of the case 18, respectively.
[0016]
A core assembly 30 is inserted into the longitudinal holes 16, 20 a and 22 a of the case 18, the elastic body 20 and the stripper 22 so as to be movable in the axial direction. The core assembly 30 includes a rod body 34 having rollers 31 and 32 that are cam followers at the upper end, a cap-shaped member 37 coupled to the lower end of the rod body 34 by a bolt 36, and a screw coupling to the lower end of the cap-shaped member 37. And a male assembly 38 formed. The lower end portion of the male mold assembly 38 constitutes a male mold 40. A stationary annular cam block 42 is disposed at an upper position of the compression molding apparatus 2, and annular cams 44 and 46 are formed on the cam block 42. The roller 31 is engaged with the cam 44 and the roller 32 is engaged with the cam 46, respectively. As the mold means 10 rotates, the rollers 31 and 32 and the annular cams 44 and 46 cooperate to raise and lower the core assembly 30 as required.
[0017]
The lower mold assembly 14 includes a cylindrical case 50 having a vertical hole 49 whose upper end is open and whose lower end is defined by a bottom portion 48. The case 50 is supported by the rotary support 6 so as to be movable up and down. The case 50 includes rollers 52 and 54 as cam followers at the lower end. A stationary annular cam block 56 is disposed at a lower position of the compression molding apparatus 2, and annular cams 57 and 58 are formed on the cam block 56. The roller 52 is engaged with the cam 57 and the roller 54 is engaged with the cam 58, respectively. The vertical hole 49 of the case 50 includes three vertical holes 49a, 49b, and 49c having an inner diameter that is sequentially increased from the bottom 48 toward the upper end. In the vertical hole 49 of the case 50, a fluid spring unit 60, which is an elastic means for defining the molding pressure, is detachably accommodated. The fluid spring unit 60 has a cylinder 62, a piston 64 disposed in the cylinder 62, and a compressible fluid (not shown) filled between the cylinder 62 and the piston 64. , An elastic fluid that returns to its original volume when the compressive force is released and has an elastic function similar to that of a spring). As shown in FIG. 2, a part of the piston 64 (piston rod) protrudes from the lower end of the cylinder 62. A male threaded portion 66 that projects in the axial direction is disposed on the end surface of the cylinder 62 opposite to the piston 64. A preferred example of the fluid spring unit 60 is “Liquid Die Spring” (trade name) imported and sold by Meiyu Airmatic Co., Ltd. A bolt 68 for height adjustment is screwed into the bottom 48 of the vertical hole 49 of the case 50. The fluid spring unit 60 is accommodated in the vertical hole 49 by placing the end face of the piston 64 on the head of the bolt 68 attached to the bottom 48 of the vertical hole 49 of the case 50. The cylinder 62 is fitted into the vertical hole 49a having the smallest inner diameter so as to be movable in the axial direction, and the upper end portion of the cylinder 62 including the male screw portion 66 projects into the vertical hole 49b having a larger inner diameter than the vertical hole 49a. It is positioned.
[0018]
A female screw portion 70 is formed at the lower end portion where the inner diameter of the vertical hole 49c is slightly smaller. The internal diameter of the female thread portion 70 is larger than the internal diameter of the vertical hole 49b.bigA shoulder portion is formed between the lower end of the female screw portion 70 and the upper end of the vertical hole 49b. A cylindrical member 72 is detachably coupled to the male thread portion 66 of the cylinder 62. The cylindrical member 72 includes a large diameter portion 72a, a small diameter portion 72b, and a shoulder portion formed between the large diameter portion 72a and the small diameter portion 72b. A large diameter hole and a small diameter hole are formed in the cylindrical member 72 along the axis, the large diameter hole is opened at the lower end of the large diameter portion 72a, and the small diameter hole is opened at the upper end of the small diameter portion 72b. A female screw portion 72c is formed at the lower end portion of the large diameter portion 72a, and hence the lower end portion of the large diameter hole, and a female screw portion 72d is formed at the small diameter hole. The cylindrical member 72 is detachably coupled to the cylinder 62 when the female screw portion 72 c of the large diameter portion 72 a is screwed into the male screw portion 66 of the cylinder 62. The shoulder portion of the cylindrical member 72 is positioned so as to protrude slightly upward from the shoulder portion at the upper end of the vertical hole 49b. A hollow male screw member 74, which is an initial load setting means, is threadably engaged with the female screw portion 70 at the lower end of the vertical hole 49c. The hollow male screw member 74 is formed with a male screw on the outer peripheral surface, a through hole extending in the axial direction is formed in the center, and is screwed into the upper end in the axial direction with a tool from the open upper end of the vertical hole 49c. A locking groove is formed so that a screwing release operation can be performed. The small-diameter portion 72b of the cylindrical member 72 is inserted into the through hole of the hollow male screw member 74 so as to be relatively movable, and the shoulder portion of the cylindrical member 72 is brought into contact with the lower end surface of the hollow male screw member 74 to prevent upward movement. Is done. When the hollow male screw member 74 is screwed into the female screw portion 70 by a predetermined amount, the cylindrical member 72 is pushed downward by a predetermined amount in the axial direction via the shoulder portion. As described above, the hollow male screw member 74 holds the cylinder 62 of the fluid spring unit 60 in a state in which the cylinder 62 is forcibly moved by a predetermined amount with respect to the piston 64 and prevents upward movement. A predetermined amount of the compressible fluid in the fluid spring unit 60 is compressed, and an initial load is set.
[0019]
A support member 75 is detachably coupled to the upper end of the small diameter portion 72b of the cylindrical member 72. The support member 75 includes a cylindrical portion 77 having a locked hole 76 and a flange portion 78 that extends radially outward from one end of the cylindrical portion 77. One end of the locked hole 76 is opened to one end of the flange portion 78, and the other end of the locked hole 76 is defined by a bottom formed at the other end portion of the cylindrical portion 77. A through hole is formed at the center of the bottom of the locked hole 76. The support member 75 is detached by a bolt 79 in a state where the cylindrical portion 77 is removably inserted into the vertical hole 49 c of the case 50 and the lower end of the cylindrical portion 77 is placed on the upper end of the small diameter portion 72 b of the cylindrical member 72. Freely combined. The support member 75 is positioned with a predetermined gap between the lower surface of the flange portion 78 and the upper end surface of the case 50. The cylindrical member 72, the support member 75, and the bolt 79 constitute a support assembly that is coupled to the fluid spring unit 60. The lower die assembly 14 includes a female die assembly 80 and a friction locking member 90, and the female die assembly 80 is detachable from the support member 75 via the friction locking member 90, as will be described in detail later. Are combined. The female mold assembly 80 includes a female mold (cavity) 82 and a cooling water flow path 84. The female mold 82 is disposed at the upper end of the female mold assembly 80, and the cooling water channel 84 is disposed so as to surround the female mold 82. One end and the other end of the cooling water channel 84 are opened at one side of the female assembly 80, and a hose (not shown) for supplying and discharging cooling water to and from the cooling water channel 84 can be freely detached from these openings. Connecting joints 86 and 88 are provided. When the mold means 10 is driven to rotate, the rollers 52 and 54 and the annular cams 57 and 58 cooperate to move the lower mold assembly 14 including the case 50 and the female mold assembly 80 as required. Move up and down. The rollers 31 and 32 and the annular cams 44 and 46 in the upper die assembly 12 and the rollers 52 and 54 and the annular cams 57 and 58 in the lower die assembly 14 constitute mold opening / closing means.
[0020]
Referring to FIGS. 6 and 7, the friction locking body 90 is provided with a locking sleeve portion 92 having a locking through-hole 91 and a radial sleeve extending from one end of the locking sleeve portion 92. And an annular flange portion 93. An annular sealed space portion 94 is formed inside the locking sleeve portion 92 and the annular flange portion 93 so as to surround the outer periphery of the locking through hole 91. In the annular flange portion 93, a liquid filling hole 95 is formed so as to extend from the outer peripheral surface of the annular flange portion 93 toward the inside. A female screw portion 96 is formed on the open end side of the filling hole 95. A communication hole 97 that connects the filling hole 95 and the sealed space portion 94 is formed inside the annular flange portion 93. A part of the sealed space portion 94, the communication hole 97, and the filling hole 95 maintains a constant volume without substantially changing even when it receives a compressive force such as an incompressible liquid as a pressure medium (for example, brake oil). Liquid) is filled through the filling hole 95, and the sealing pressure screw 98 is screwed into the female thread portion 96 of the filling hole 95, whereby the incompressible liquid is sealed. Reference numeral 99 is a set screw for preventing the sealing pressure screw 98 from being detached, and can be freely detached from a seat portion 93 a formed on the outer peripheral surface of the annular flange portion 93 on the open end side of the filling hole 95. It is screwed.
[0021]
Referring to FIG. 2 together with FIGS. 6 and 7, a supported rod 89 is disposed on the female assembly 80 so as to protrude from the flat bottom end surface. The friction locking body 90 is configured such that the locking sleeve portion 92 is detachably fitted into the locked hole 76 of the support member 75 and the annular flange portion 93 is superposed on the flange portion 78 of the support member 75. , Temporarily attached to the support member 75. In the female assembly 80, the supported rod 89 is removably fitted into the locking through hole 91 of the friction locking body 90, and the lower end surface of the female assembly 80 is an annular flange of the friction locking body 90. By being superposed on the portion 93, it is temporarily attached to the friction locking body 90. Subsequently, the sealed incompressible liquid is pressurized by tightening the sealing pressure screw 98 of the friction locking body 90. As a result, the outer peripheral surface of the locking sleeve portion 92 of the friction locking body 90 is expanded in diameter, and the inner peripheral surface of the locking through hole 91 that is the inner peripheral surface of the locking sleeve portion 92 is reduced in diameter. The locking body 90 is firmly frictionally locked (friction coupled) to the support member 75, and the supported rod 89 of the female assembly 80 is firmly frictionally locked to the friction locking body 90. As a result, the female mold assembly 80 is detachably coupled to the support member 75 via the friction locking body 90. Preferable examples of the friction locking member 90 include a friction joint manufactured by Miki Pulley Co., Ltd.—ETP bushing / positive lock (trade name) and model name “ETP”. The upper die assembly 12 and the lower die assembly 14 configured as described above are positioned on a substantially common vertical axis.
[0022]
In the lower mold assembly 14 as described above, the fluid spring unit 60 is used as an elastic means for defining the molding pressure of the synthetic resin material. Therefore, the hollow male screw member 74 can be easily and reliably tightened. An initial load can be set (substantially without error). Therefore, the molding pressure obtained by compressing the fluid spring unit 60 by a predetermined amount during molding, which will be described later, is substantially set to a predetermined value, and the predetermined molding pressure is stably secured over a long period of time. As a result, the number of times the apparatus is stopped can be reduced, and thus the production efficiency can be improved. Further, unlike the prior art, shim adjustment work for securing a predetermined molding pressure and disk spring replacement work are not required, so that production efficiency can be improved in this respect as well. Furthermore, since the fluid spring unit 60 can be set by simply inserting it into the vertical hole 49 of the case 50 with the cylindrical member 72 assembled, its mounting and taking out operations are extremely easy. Therefore, the replacement work is remarkably facilitated. In the above-described embodiment, the fluid spring unit 60 is disposed in the lower mold assembly 14, but there is an embodiment in which the fluid spring unit 60 is disposed in the upper mold assembly 12 instead of the fluid spring unit 60. can get. As the compressive fluid of the fluid spring unit 60, a liquid is suitable when a relatively high molding pressure is required, and a gas (for example, nitrogen gas) is suitable when a relatively low molding pressure is required.
[0023]
In the lower die assembly 14 as described above, the female die assembly 80 is also configured to be detachably fixed to the support member 75 constituting the upper end portion of the support assembly via the friction locking member 90. As a result, it can be assembled with a single touch. As a result, when the female assembly 80 is replaced or when the female assembly 80 is cleaned, attachment / detachment can be performed remarkably easily, and thus the production efficiency can be improved. Further, since there is no need for screw connection as in the prior art, that is, the female assembly 80 can be mounted by simply inserting the female assembly 80 in the axial direction without rotating, so that the circumferential direction of the female assembly 80 can be reduced. Positioning can be performed remarkably easily. Therefore, the positions of the joints 86 and 88 can be easily and accurately positioned at predetermined positions, which is extremely useful in practice.
[0024]
Next, the outline of the compression molding process of the compression molding apparatus 2 will be described more specifically with reference to FIGS. 3 to 5 omit the cross-sectional hatching of each member for easy understanding. In this embodiment, when the mold means 10 is rotated once by the rotational drive of the rotary support 6, the upper mold assembly 12 has the case 18 and the stripper coupled to the case 18 by the mold opening / closing means described above. 22 is configured so that only the core assembly 30 is raised and lowered without being raised and lowered, and the lower die assembly 14 is entirely raised and lowered. When the mold means 10 is moved to the synthetic resin material supply area A, the core assembly 30 of the upper mold assembly 12 is raised and positioned at a predetermined uppermost portion, and the male mold 40 at the lower end is moved to the stripper 22. It is positioned above the lower surface of. The lower mold assembly 14 is lowered to a predetermined position.BottomPositioned on. The upper mold assembly 12 and the lower mold assembly 14 are separated as much as possible. Then, the synthetic resin material 100 is supplied from the synthetic resin material supply means 7 into the female mold 82 of the lower mold assembly 14 (see FIG. 3A). Next, while the mold means 10 passes through the molding zone B, the lower mold assembly 14 is raised and the upper surface of the female mold assembly 80 is pressed against the lower surface of the stripper 22 of the upper mold assembly 12 (so-called “so-called”). Clamping is carried out). The elastic body 20 on the stripper 22 side is bent by a predetermined amount, and the flange 26 of the stripper 22 is raised by a predetermined amount along the bolt 28 (a predetermined amount between the lower surface of the flange 26 and the head of the bolt 28). Gaps are formed). On the other hand, the fluid spring unit 60 of the lower mold assembly 14 is also compressed by a predetermined amount, and the gap between the lower surface of the flange portion 78 of the support member 75 and the upper end surface of the case 50 is reduced by a predetermined amount from the initial setting gap. (See FIG. 3-B).
[0025]
In the molding area B, the core assembly 30 is further lowered to a predetermined lowermost portion, and a molding space is formed between the female mold 82, a part of the lower surface of the stripper 22 and the male mold 40, and the synthetic resin material 100. Is compressed to form a synthetic resin container lid 200 (see FIG. 4-A). Next, while the mold means 10 passes through the cooling zone C, there is no relative movement between the core assembly 30 and the lower mold assembly 14, and the compression molding state is maintained. Cooling of the container lid 200 is performed. While the mold means 10 is moved from the downstream end of the cooling zone C toward the molded product discharge zone D, the lower die assembly 14 is lowered and the female die 82 is released from the synthetic resin container lid 200. The synthetic resin container lid 200 is held by the male mold 40 (see FIG. 4-B). When the mold means 10 is moved to the molded product discharge area D, the lower mold assembly 14 is lowered to a predetermined lowermost position, while the core assembly 30 is raised to a predetermined uppermost position, so that the male mold 40 is positioned above the lower surface of the stripper 22. As a result, the male mold 40 is forcibly removed from the synthetic resin container lid 200 and released from the mold, and the synthetic resin container lid 200 is stripped by the stripper 22 and is allowed to fall freely and at the same time is taken out by air ejected from the air pipe 8a. It is forcibly moved to 8b and the carry-out is completed. The above compression molding process (cycle) is repeatedly performed for each mold means 10, and the synthetic resin container lid 200 is continuously compression molded.
[0026]
Next, with reference to FIG.8 and FIG.9, the stripper 22 which is other embodiment of this invention is demonstrated. At least two knockouts 300 (two in the embodiment) are disposed in the stripper 22 at intervals in the circumferential direction. Each of the knockouts 300 includes a working position (a position shown in FIG. 9) in which each lower surface 302 protrudes a predetermined amount from the lower surface 22 b of the stripper 22, and a non-alignment in which each lower surface 302 is aligned with the lower surface 22 b of the stripper 22. Two spring members 304 (only one of them is shown in FIG. 9) that are movably disposed between the operating positions (not shown) and are disposed between the stripper 22 and the operating position. ) Is always urged to be positioned at the operating position. When the upper mold assembly 12 and the lower mold assembly 14 are brought close to each other by the mold opening / closing means described above and the upper surface of the female mold assembly 80 and the lower surface 22b of the stripper 22 are pressed against each other, the knockout 300 Each is configured to be moved from the working position against the corresponding spring member 304 and positioned in the non-working position.
[0027]
This will be described more specifically. The stripper 22 includes a cylindrical portion 22c including the vertical hole 22a and the lower surface 22b. A pair of mounting grooves 22f having a bottom surface 22d existing in a predetermined depth position extending in the axial direction from the lower surface 22b with a predetermined circumferential width are formed at symmetrical positions of the cylindrical portion 22c with respect to the axis. Yes. Each of the bottom surfaces 22d is positioned on substantially the same plane orthogonal to the axis. The stripper 22 is further formed with a large-diameter hole 22g extending in the axial direction from each bottom surface 22d of the mounting groove 22f and a small-diameter hole 22h extending in the axial direction from each bottom surface of the large-diameter hole 22g. At the symmetrical position of the cylindrical portion 22c, a long hole 22i that is long in the axial direction is formed so as to be orthogonal to the axial line, and one end opens to the outer peripheral surface of the cylindrical portion 22c and the other end opens to the inner peripheral surface of the vertical hole 22a. ing. Each of the knockouts 300 includes a main body portion 306, a rod portion 308, and a stopper pin 310. Each body portion 306 of the knockout 300 is fitted to the corresponding mounting groove 22f so as to be movable in the axial direction and detachable, and a part of the inner peripheral surface of the vertical hole 22a of the stripper 22 and the lower surface of the stripper 22 A part of 22b is provided. Each rod part 308 of the knockout 300 protrudes from the main body part 306 in the axial direction and is fitted in the corresponding large diameter hole 22g so as to be movable in the axial direction and detachable. Each stopper pin 310 of the knockout 300 is locked to the rod portion 308 so as to be orthogonal to the axis of the rod portion 308 and project at both ends projecting from the outer peripheral surface of the rod portion 308, and both ends correspond to long holes. 22i is movably fitted. Each of the knockouts 300 is fitted into the mounting groove 22f corresponding to the main body portion 306, the large diameter hole 22g corresponding to the rod portion 308, and the long holes 22i corresponding to both ends of the stopper pin 310, respectively. Mounted on the stripper 22. The spring member 304 is inserted into each of the small diameter holes 22 h of the stripper 22. Each of the spring members 304 acts on the rod portion 308 of the corresponding knockout 300 to constantly bias the knockout 300, and the above-described operation position of each of the knockouts 300 is one end of the long hole 22i corresponding to each of the stopper pins 310. It is comprised so that it may be prescribed | regulated by contacting (lower end of FIG. 9).
[0028]
Referring also to FIG. 1, when the mold means 10 is moved to the molded product discharge area D as described above, the core assembly 30 is raised to a predetermined uppermost position, and the male mold 40 is moved from the lower surface of the stripper 22. Is also positioned above. As a result, the male mold 40 is forcibly removed from the synthetic resin container lid 200 and released from the mold, and the synthetic resin container lid 200 is stripped by the stripper 22 and freely dropped onto the carry-out chute 8b to complete the carry-out. In this case, conventionally, when a vacuum is generated between the core assembly 30 and the synthetic resin container lid 200, the synthetic resin container lid 200 may be attracted to the lower surface 22 b of the stripper 22 and not fall freely. Arise. However, in the present invention, since the two knockouts 300 are disposed in the stripper 22 as described above, even if a vacuum is generated as described above, each of the knockouts 300 is separated by the spring members 304. The synthetic resin container lid 200 is not attracted to the lower surface 22b of the stripper 22 and is forcibly dropped. As a result, the molded synthetic resin container lid 200 can be smoothly and reliably dropped from the lower surface 22 b of the stripper 22. Since the synthetic resin container lid 200 can be smoothly and reliably dropped from the lower surface 22b of the stripper 22, it can collide with a guide (not shown) for discharging a molded product provided in the molded product discharge area D and be dropped. And the damage and deformation of the synthetic resin container lid 200, which is a molded synthetic resin article, can be prevented. Therefore, the occurrence of defective products can be reduced.
[0029]
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, Furthermore, various other various, without deviating from the scope of the present invention. Can be modified or modified. For example, there is another embodiment in which the fluid spring unit 60 is accommodated in the case 50 in the upside down direction with respect to the above embodiment. In this case, the lower end of the cylinder 62 is placed on the bolt 68, and a male thread portion is formed on the piston 64.
[0030]
According to a compression molding apparatus for a synthetic resin article according to the present invention.IfThe molded synthetic resin article can be dropped smoothly and reliably from the lower surface of the stripper. In addition, damage and deformation of the molded synthetic resin article can be prevented.. MaIn addition, the occurrence of defective products can be reduced.
[Brief description of the drawings]
FIG. 1 is a simplified plan view showing an embodiment of a compression molding apparatus for a synthetic resin article constructed according to the present invention.
FIG. 2 is a longitudinal sectional view of an upper mold assembly and a lower mold assembly provided in the compression molding apparatus shown in FIG.
3 is a longitudinal sectional view partially showing a separated state and an approaching state (clamping state) of the upper die assembly and the lower die assembly shown in FIG. 2. FIG.
4 is a longitudinal sectional view partially showing a molding state and a separation state (a separation state of the lower die assembly) of the upper die assembly and the lower die assembly shown in FIG. 2;
5 is a longitudinal sectional view partially showing a state in which the core assembly is lifted (with the synthetic resin container lid removed) in a separated state of the upper die assembly and the lower die assembly shown in FIG. 2; .
6 is a front view of a friction locking body provided in the lower mold assembly shown in FIG. 2. FIG.
7 is a view of the friction locking body shown in FIG. 6 as viewed from the left.
FIG. 8 is a bottom view of a stripper according to another embodiment of the present invention.
9 is a cross-sectional view taken along the line AA in FIG.
[Explanation of symbols]
2 Compression molding equipment
10 Mold means
12 Upper die assembly
14 Lower mold assembly
18 cases
20 Elastic body
22 Stripper
22a Vertical hole
28 volts
30 Core assembly
38 Male assembly
40 male
50 cases
60 Fluid spring unit
74 Hollow male screw member (initial load setting means)
75 Support members
80 Female assembly
82 female
90 Friction locking body
100 Synthetic resin material
200 Plastic container lid
300 knockout

Claims (1)

An upper mold assembly and a lower mold assembly that cooperate with each other, and a mold opening / closing means that moves the upper mold assembly and the lower mold assembly relative to each other so as to approach and separate from each other. The assembly includes a stripper having a vertical hole, and a core assembly that is disposed so as to be moved up and down in the vertical hole of the stripper by the mold opening / closing means and has a lower end portion constituting a male mold. The mold assembly includes a female mold, and when the upper mold assembly and the lower mold assembly are brought close to each other by the mold opening and closing means, the upper surface of the female mold and the lower surface of the stripper are pressed against each other, The core assembly is lowered so that the male mold protrudes from the lower surface of the stripper into the female mold, thereby forming a portion between the female mold, a part of the lower surface of the stripper, and the male mold. Space is formed and the synthetic resin material supplied is compression molded in the molding space In the compression molding apparatus of the synthetic resin article to be crimped,
The stripper is provided with at least two knockouts spaced in the circumferential direction, and each of the knockouts has an operation position in which each lower surface protrudes from the lower surface of the stripper by a predetermined amount, and each lower surface. Is urged to be positioned at the working position by a spring member disposed between the stripper and a non-working position aligned with the lower surface of the stripper and with the spring member disposed between the stripper and the mold. When the upper die assembly and the lower die assembly are brought close to each other by the opening and closing means, and the upper surface of the female die and the lower surface of the stripper are pressed against each other, each of the knockouts corresponds to the corresponding spring. Moved from the working position against the member and positioned in the non-working position;
The stripper includes a cylindrical portion including the vertical hole and the lower surface, and the cylindrical portion has a predetermined depth position extending in the axial direction from the lower surface with a predetermined circumferential width at a symmetrical position across the axis. A pair of mounting grooves having a bottom surface existing on the stripper, and a stripper having a large diameter hole extending in the axial direction from each bottom surface of the mounting groove, and an axial direction extending from the bottom surface of each large diameter hole. A long hole extending in the axial direction is perpendicular to the axis, and one end is opened on the outer peripheral surface of the cylindrical portion, and the other end is the vertical hole. Each of the knockouts is fitted to the corresponding mounting groove so as to be movable in the axial direction and detachable, and the inner peripheral surface of the vertical hole of the stripper. And a main body having a part of the lower surface of the stripper and the main body A rod portion projecting in the axial direction and fitted to the corresponding large-diameter hole so as to be movable in the axial direction and detachable, and to both ends of the rod portion perpendicular to the axis of the rod portion And a stopper pin that is movably fitted in the corresponding long hole, and the main body portion is fitted in the corresponding mounting groove. The rod portion is fitted to the stripper by being fitted into the large-diameter hole to which the rod portion corresponds, and the long holes to which the both ends of the stopper pin correspond to each of the small-diameter holes of the stripper. The spring members are inserted, and each of the spring members acts on the rod portion of the corresponding knockout to constantly bias the knockout, and the working position of each of the knockouts is determined by each of the stopper pins. Of the corresponding slot Is defined by contact with the end,
A compression molding apparatus for synthetic resin articles.

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