JP2014201050A - Vacuum molding apparatus - Google Patents

Abstract

A vacuum molding apparatus capable of suitably molding a resin product having a rising portion. A vacuum forming apparatus (1) for molding a resin product having a base, a support part formed on the back side of the base part, and a rising part standing on the surface side of the base part. The second molding provided with the first mold 2 provided with the first cavity 40 for molding the support portion, the second cavity 41 for molding the rising portion, and the injection means 33 for injecting the resin into the second cavity 41. It has a mold 3, a suction means 13 for sucking the resin sheet S to the first mold 2, and a punching means 14 for opening a hole T in the resin sheet S. At the time of molding, the resin sheet S is placed in the first mold 2. A hole T is made in the resin sheet S while adsorbing the resin, and the injection means 33 injects the resin into the first cavity 40 and the second cavity 41 communicated by the hole T. [Selection] Figure 3

Description

  The present invention relates to a vacuum forming apparatus.

  A vacuum forming apparatus is known as an apparatus for integrally molding a resin product (see Patent Document 1). The vacuum forming apparatus is an apparatus for forming by adsorbing a resin sheet to a forming die.

  Here, a case where a resin product including a base portion and a rising portion standing on the base portion is integrally formed using a vacuum forming apparatus will be considered. FIG. 4 is a schematic view showing a case where a resin product is manufactured using a conventional vacuum forming apparatus, where (a) shows before molding and (b) shows after molding. Here, a case where a rising portion having a small width (plate thickness) and a high height is formed is illustrated.

  As shown in FIG. 4A, the conventional vacuum forming apparatus 100 is mainly composed of a plug 101, a forming die 111, and a vacuum pump (not shown). The plug 101 includes an erecting portion 102 that erects perpendicularly to the plug 101. The molding die 111 is formed with a concave groove portion 112 having a rectangular cross section and a plurality of suction holes 113 connected to a vacuum pump. When the resin of the resin sheet S enters the concave groove portion 112, a rising portion is formed.

JP 2009-39862 A

  When forming a rising portion having a small width and a large height, the width of the concave groove portion 112 is also elongated accordingly, so that the resin sheet S is adsorbed on the surface of the concave groove portion 112 only by suction of the vacuum pump. It becomes difficult. Therefore, for example, it is conceivable that the resin sheet S is pushed by the standing portion 102 of the plug 101 and the resin is fed into the concave groove portion 112. However, as shown in FIG. There is a possibility that the resin sheet is pulled between the installation part 102 and the resin sheet S is broken. Even if the groove 112 can be sucked, there is a problem in that a space leading to the outside is formed as the standing portion 102 is retracted.

  The present invention was created to solve such problems, and an object of the present invention is to provide a vacuum forming apparatus capable of suitably forming a resin product having a rising portion.

  The present invention is a vacuum molding apparatus for molding a resin product including a base, a support formed on the back side of the base, and a rising portion that is continuous with the support and is provided upright on the surface of the base. A second mold having a first mold having a first cavity for molding the support part, a second cavity for molding the rising part, and an injection means for injecting resin into the second cavity; A suction means for sucking a resin sheet to the first mold or the second mold; and a punching means for opening a hole in the resin sheet. During the molding, the first mold or the second mold A hole is made in the resin sheet while adsorbing the resin sheet, and the injection means injects the resin into the first cavity and the second cavity communicated by the hole.

  According to such a configuration, the resin is injected and molded into the first cavity and the second cavity communicated by opening the hole while making a hole in the resin sheet. Thereby, a resin product can be shape | molded easily. In addition, the rising portion is formed by the second cavity, and the resin also enters the back side of the resin sheet through the hole to form the support portion. Therefore, the rising portion can be firmly fixed to the base portion. .

  Moreover, it is preferable to provide a temperature adjusting means in the vicinity of the second cavity. According to this structure, it can prevent that resin hardens | cures by heating, and can accelerate | stimulate hardening of resin by cooling. Thereby, a moldability can be improved.

  According to the vacuum forming apparatus according to the present invention, a resin product provided with a rising portion can be suitably formed.

It is a schematic sectional drawing of the vacuum forming apparatus which concerns on embodiment of this invention. It is a perspective view of the resin product which concerns on this embodiment. It is a manufacturing method of the resin product which concerns on this embodiment, Comprising: (a) shows a perforation process, (b) shows a cavity formation process, (c) shows an injection process. It is the schematic which shows the case where a resin product is manufactured using the conventional vacuum forming apparatus, Comprising: (a) shows before shaping | molding, (b) shows after shaping | molding.

  Embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, the vacuum forming apparatus 1 according to the present embodiment is mainly composed of a first forming die 2 and a second forming die 3. The vacuum forming apparatus 1 is an apparatus for forming a resin product J shown in FIG.

  As shown in FIG. 2, the resin product J includes a base portion J1, a rising portion J2, a base end portion J3, and a support portion J4. The base J1 is a part that exhibits a plate shape. The rising portion J2 has a plate shape and rises with respect to the base portion J1.

  The base end portion J3 is a portion formed on the surface J1a side of the base portion J1 at the base end of the rising portion J2. The base end portion J3 is formed continuously with the rising portion J2.

  The support portion J4 is a portion formed with a predetermined thickness on the back surface J1b side of the base portion J1. The support part J4 is formed continuously from the rising part J2 and the base end part J3. The base portion J3 and the support portion J4 are configured to sandwich the base portion J1. In the center of the support portion J4, a punch groove J4a formed by retreating a perforated portion 23b described later is formed.

  In the present embodiment, the base end portion J3 and the support portion J4 are formed at two locations with respect to the rising portion J2, but may be one location or three or more locations. Further, the base end portion J3 and the support portion J4 may be formed continuously in the length direction of the rising portion J2.

  As shown in FIG. 1, the first mold 2 mainly includes a frame 11, a first mold body 12, suction means 13, and perforation means 14.

  The frame 11 is a part that constitutes the outline of the first mold 2. The frame 11 includes a first frame 15 disposed horizontally and a second frame 16 and a third frame 17 disposed perpendicular to the first frame 15 and spaced apart from each other.

  The first mold body 12 is separated from the first frame 15 and is fixed to the second frame 16 and the third frame 17. A suction chamber 22 is formed by the first frame 15, the second frame 16, the third frame 17, and the first mold body 21. The first mold body 12 is formed with a plurality of suction holes P1 formed along the height direction. One end side of the suction hole P1 opens to the suction surface K1, and the other end side opens to the suction chamber 22. A moving space 21 a that is a hollow portion extending in the height direction is formed at the center of the first mold body 12. The moving space 21a is formed so that a moving body 23 described later can move in the height direction.

  The suction means 13 is installed in the second frame 16 and depressurizes the inside of the suction chamber 22. The suction means 13 is constituted by a vacuum pump in this embodiment.

  The punching means 14 is composed of a moving body 23 and a cylinder 24. The moving body 23 has a base portion 23a having a columnar shape and a perforated portion 23b formed on an end surface of the base portion 23a. The perforated part 23b has a conical shape. The perforated part 23 b is a part that opens a hole T in the resin sheet S. Note that when the moving body 23 is advanced (raised) by driving the cylinder 24, the perforated portion 23b protrudes from the suction surface K1. On the other hand, when the moving body 23 is retracted (lowered), the perforated portion 23b is completely accommodated in the suction surface K1. The piercing portion 23b may be constituted by a drill member, or may be pierced by rotating the moving body 23.

  The second mold 3 includes a frame 31, a second mold body 32, an injection unit 33, and a temperature adjustment unit 34. The frame 31 is a part constituting the outline of the second mold 3. The frame 31 includes a first frame 35 disposed horizontally, and a second frame 36 and a third frame 37 disposed perpendicular to the first frame 35 and spaced apart from each other.

  The second mold body 32 is separated from the first frame 35 and is fixed to the second frame 36 and the third frame 37. In the center of the second mold body 32, a second cavity 41, which is a space filled with resin, is formed. The second cavity 41 includes a rising portion cavity 41a for forming the rising portion J2 and a proximal end portion cavity 41b for forming the proximal end portion J3. The base end cavity 41b has a concave shape and is open to the first mold 2 side.

  The injection means 33 is a device that injects molten resin into the cavity. Examples of the injection means 33 include a known pre-plunger type injection molding machine. The pre-plunger injection molding machine injects a molding material kneaded by rotation and heating of a screw into an injection chamber and then injects it from an injection member such as a plunger. FIG. 1 shows only some of the injection members such as a plunger among the components of the pre-plunger type injection molding machine. The periphery of the lower end of the injection member is attached to the injection mold 3 so as to penetrate vertically, and the injection port at the tip of the injection member faces the rising portion cavity 41a.

  The temperature adjusting means 34 is disposed in the vicinity of the second cavity 41. The temperature adjusting means 34 can adjust the temperature of the second mold body 32.

  Next, the manufacturing method of the resin product which concerns on embodiment of this invention is demonstrated. Here, the case where the resin product J is manufactured using the vacuum forming apparatus 1 is illustrated. In the method for producing a resin product according to the present embodiment, a sheet placement process, a suction / piercing process, a cavity forming process, and an injection process are performed.

  As shown in FIG. 1, in the sheet arranging step, the resin sheet S is arranged on the first mold 2. The resin sheet S uses a thermoplastic resin such as polyethylene or polypropylene. The resin sheet S is in a state that can be molded by heating in advance. Further, the temperature of the second mold 3 is adjusted by the temperature adjusting means 34.

  As shown in FIG. 3A, in the suction / piercing step, the suction means 13 is driven to punch the resin sheet S while sucking it. First, the cylinder 24 is driven and moved to a position where the perforated part 23b protrudes from the suction surface K1. And the suction means 13 is driven and the resin sheet S is adsorbed on the adsorption surface K1 by the negative pressure generated in the vicinity of the adsorption surface K1. Thereby, the perforated part 23b enters the resin sheet S, and the hole T is formed.

  As shown in FIG. 3B, in the cavity forming step, the cylinder 24 is driven to move the moving body 23 backward with respect to the resin sheet S. Thereby, the 1st cavity 40 enclosed by the resin sheet S, the movement space 21a, and the moving body 23 is formed. Further, since the moving body 23 is retracted, the first cavity 40 and the second cavity 41 communicate with each other through the hole T, and a continuous cavity is formed on the front and back of the resin sheet S.

  As shown in FIG. 3C, in the injection process, resin is injected into the first cavity 40 and the second cavity 41 by the injection means 33. And if necessary, the temperature of the temperature adjusting means 34 is lowered to accelerate the curing of the resin. Thus, the resin product J is formed.

  The manufacturing method described above is an example, and other methods may be used. For example, the resin sheet S may be sucked in a state where the perforated part 23b of the perforating means 14 is housed inside the suction surface K1, and then the perforated part 23b may enter the resin sheet S to perforate.

  According to the vacuum forming apparatus 1 according to the present embodiment described above, the resin sheet S is opened by the injection means 33 in the first cavity 40 and the second cavity 41 communicated by opening the hole T while opening the hole T. Inject. Thereby, even if the width of the rising portion J2 is narrow and long, the resin product J including the base portion J1 and the rising portion J2 standing on the base portion J1 can be easily molded. In addition, since the resin product J can be molded only by abutting the first mold 2 and the second mold 3 once, the manufacturing cycle time can be shortened.

  Further, the rising portion J2 is formed by the second cavity 41, and the resin also enters the back side of the resin sheet S through the hole T, so that the base end portion J3 and the support portion are sandwiched between the front and back of the opening edge portion of the hole T. J4 is formed. Thereby, the rising part J2 can be firmly fixed to the base part J1.

  Further, a temperature adjusting means 34 is provided in the vicinity of the second cavity 41 to prevent the resin from curing by heating the second mold body 32 and to accelerate the resin curing by cooling (lowering the temperature). Can be made. Thereby, a moldability can be improved.

  Although the embodiments of the present invention have been described above, design changes can be made as appropriate without departing from the spirit of the present invention. For example, in the present embodiment, the plate-like rising portion J2 is exemplified, but other shapes may be used as long as it includes a portion including a portion that rises slightly from the base portion J1.

  In the present embodiment, the resin sheet S is sucked into the first mold 2, but may be sucked into the second mold 3. In the present embodiment, the space formed by lowering the moving body 23 is the first cavity 40, but the present invention is not limited to this. For example, the first cavity may be formed in the first mold 2 in advance, and the hole may be formed by moving only the perforated part 23b.

  In the present embodiment, the punching means 14 is provided in the first mold 2, but it may be provided in the second mold 3. In this case, for example, a perforated part movable in the second cavity 41 is installed, a hole is made in the resin sheet, the perforated part is retracted from the second cavity 41, and then the resin is injected into the second cavity 41. do it.

  Further, in the above-described embodiment, the second mold 3 is disposed on the upper side, and the first mold 2 is disposed on the lower side. On the contrary, the first mold 2 is disposed on the upper side, and the second mold is disposed on the lower side. 3 may be arranged.

DESCRIPTION OF SYMBOLS 1 Vacuum forming apparatus 2 1st shaping | molding die 3 2nd shaping | molding die 11 Frame 12 1st type | mold main body 13 Suction means 14 Punching means 33 Injection means 34 Temperature control means 40 1st cavity 41 2nd cavity J Resin product J1 Base J2 Rising part J3 Base end J4 Support section

Claims (2)

A vacuum molding apparatus for molding a resin product having a base, a support formed on the back side of the base, and a rising portion that is continuous with the support and is provided upright on the surface of the base,
A first mold having a first cavity for molding the support part;
A second mold having a second cavity for molding the rising portion and an injection means for injecting resin into the second cavity;
Suction means for sucking a resin sheet into the first mold or the second mold;
A perforating means for perforating the resin sheet,
At the time of molding, a hole is made in the resin sheet while adsorbing the resin sheet to the first mold or the second mold, and resin is injected into the first cavity and the second cavity communicated by the hole by the injection means. A vacuum forming apparatus characterized by injecting a liquid.   The vacuum forming apparatus according to claim 1, wherein a temperature adjusting means is provided in the vicinity of the second cavity.

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