JPS6129516A - Method and apparatus for manufacturing synthetic resin composite molded shape - Google Patents

Abstract

PURPOSE:To manufacture a composite molded shape easily by simultaneously executing the injection of a first molding piece and the injection of a second resin to said molding piece in each cavity and executing a transfer into the second cavity of the first molding piece and the extraction of a finished article at the same time. CONSTITUTION:A first molding piece 7 injection-molded in a first cavity 17 is transferred into a second cavity 18 by a transfer means 20, molds 10, 11 are closed, and the next first molding piece 7 is injected in the first cavity 17 while the first molding piece 7 in the second cavity 18 is used as an insert member and a second resin is injected, thus manufacturing a composite molded shape 9 consisting of the first molding piece 7 and a second molding section 8. The resin is solidified, the molds are opened, and the first molding piece 7 is shifted to the second cavity 18 while the molded shape 9 is extracted from the mold. The process is repeated. Manufacture is facilitated, and finishing is also improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for manufacturing a synthetic resin composite molded article, and more specifically, it molds a plurality of different colored or different kinds of synthetic resins at the time of mold closing, and adjusts the relationship between one insert and the other. When the mold is opened, a cycle of transferring one molded piece to the other cavity to be inserted is repeated, or a cycle of transferring a plurality of molded pieces of one to a cavity to be inserted of the other is repeated, or one A synthetic resin composite molded product in which a progressive cycle is repeated in which a molded piece is transferred to the other cavity to be inserted to form a composite molded piece, and this composite molded piece is further transferred to the other cavity to be inserted. The present invention relates to an efficient and rational manufacturing method and a simple manufacturing apparatus for the purpose comprising independent first cavities, second cavities, etc., and a device for transferring molded pieces between them.

Composite molded products made by joining together different colored or different synthetic resin parts are used in a wide variety of ways, such as instrument covers, magnetic tape cases, display boards, daily necessities such as trays and pots.

Conventionally, when molding a product by integrally joining two or more types of synthetic resin pieces, there have been methods such as molding each synthetic resin piece in separate processes and bonding them with adhesive, or separating pre-formed synthetic resin pieces. There is a method of inserting it into a cavity and molding it integrally, but both methods involve complicated processes and have quality problems such as adhesive extrusion and cracking at the joint.

In addition, as shown in Fig. 11, movable molds C and D of the same shape as the irregularly shaped fixed molds A and B are provided, and the movable molds C and D are fixedly mounted on a rotary mold mounting plate, and the movable molds C and D are fixedly mounted on a rotary mold mounting plate so that the rotation of the rotary mold mounting plate allows The correspondence between A-C and B-D and the correspondence between A-D and 'B-C can be taken alternately, and A, l! : The mold cavity C or D has a shape that is spatially included in the mold cavities B and C or D. Then, the synthetic resin P is molded in the mold cavity A-C, the mold is opened with the molded product attached to the movable mold C, the mold is rotated 180 degrees, and the mold is closed with the mold combination B-C. , the synthetic resin piece Q is joined with the molded product of the synthetic resin piece P.
is formed. On the other hand, a synthetic resin piece is molded in the mold cavities A-D, which are combined by the above-mentioned 180° rotational movement. There is a method in which the molded product in mold C is knocked out when the mold is opened next, and the molded product is rotated 180 degrees again, and the same cycle is repeated (Japanese Patent Publication No. 16794/1983). Although this method simplifies the manufacturing process, it requires the two movable molds C and D to be precisely assembled with the fixed molds A and B, making the molds expensive and difficult to assemble. In addition to being time consuming, there are other drawbacks such as the heavy molds must be moved so as to be assembled alternately for each cycle.

Furthermore, as shown in Figure 12, recently used for magnetic tape cases, etc. The movable core is moved forward and backward, the remaining part of the cavity is used as a first molded part, the first resin path is exposed to this first molded part, a first synthetic resin is molded, and then the movable core is molded into a movable mold. The second molded part of the cavity is made by moving it slightly backward toward the mold, and the second synthetic resin is molded with the second resin path exposed to this second molded part. There is a method to take out a composite molded product in which the two molded parts are joined.This method does not require moving a heavy mold and the equipment becomes compact, but the shape of the composite molded product is limited, and The second molded part must be molded after the first molded part has been molded, resulting in a longer molding cycle and the need to prepare a large number of devices for mass production.

The object of the present invention is to eliminate the drawbacks of the prior art, to provide a simple manufacturing process, a good finish to the molded product, no restrictions on shape, and good mass production efficiency.
The first molded piece and the second molded part are integrated by inserting the first molded piece molded with the resin into the second cavity and molding the second molded part with the second resin. In a method for manufacturing a synthetic resin composite molded product that is joined together,
When the mold is closed, the first molded piece and the second molded part are molded almost simultaneously, and when the mold is opened, when the molded product is taken out from the second cavity and the first molded piece is inserted into the second cavity. A method for manufacturing a synthetic resin composite molded product characterized by repeating a cycle of the above, and a split mold in which the split surfaces approach and separate to open and close the mold, and the split mold is connected to a first resin path formed when the mold is closed. a first cavity for molding a first molded piece; and a second cavity for inserting the first molded piece and molding a second molded part, the cavity being connected to the second resin passage; 2 cavities are provided, and when the mold is opened, the first molded in the first cavity is
An object of the present invention is to provide an apparatus for manufacturing a synthetic resin composite molded product, characterized in that it is provided with means for transporting the molded piece to the insert position of the second cavity.

Embodiments of the present invention will be described in detail below with reference to the drawings.

1 to 6 show an embodiment of the apparatus for manufacturing a synthetic resin composite molded article according to the present invention.

Reference numeral 1 denotes a fixed plate to which a fixed mold 10 is fixed.

Reference numeral 2 denotes a movable platen, which moves forward and backward as the tip 4 of a mold opening/closing cylinder (not shown) moves, guided by a tie bar 3 and fixed to the back, and has a movable mold 11 integrally fixed on its surface. 10
It is mounted so that it moves opposite to the

The fixed mold lO and the movable mold 11 constitute a pair of molds that come into contact with each other at the dividing plane, and the fixed mold 10 has a mold for molding the first molded piece, as clearly shown in FIG. A first cavity 17.17 and a first resin channel 15 communicating these with the first injection device 5, as well as a second cavity 18.18 for molding a second molded part and a second A second resin passage 16 is provided which communicates with the injection device 6 of the invention.

Note that both the first injection device 5 and the second injection device 6 are inserted and retracted into the nozzle introduction hole 12 provided in the fixed plate 1, and the end portions of the resin passages 15 and 16 provided in the fixed mold 10 are inserted into and retracted from each other. and each injection port can be connected. FIG. 6 shows the injection device 6.

Furthermore, a transfer means 20 for transferring the first molded piece 7 to a predetermined position in the second cavity 18 is provided on the side of the first cavity 17.17.

This transfer means 20 mainly consists of a member that attracts or grips the first molded piece 7, and a transfer means that transfers it to the cavity 18.

21 is a frame guided by one tie bar 3.3,
Piston 26 of forward/backward cylinder 25 supported by fixed platen 1
The moving cylinder 23 is connected to the tip of the cylinder and moves forward and backward in the mold opening/closing direction.
A movable piston 2 having a suction member 22 at its tip.
4 is driven. 27 is a guide bar.

Next, the operation will be explained from the mold closed state. After the mold is closed, first, the first injection device 5 injects and fills the first cavity 17 via the first resin path 15, and the -l molded piece is filled. Mold 7. Then, the mold is opened, the movable cylinder 23 is operated, the suction member 22 is advanced to the position of the first cavity 17, and the first molded piece 7 is suctioned and held by the retraction cylinder 25. Note that a protrusion device (not shown) is provided in the fixed mold 10 to release the mold from the first cavity 17. In addition, the resin path 15 and the first cavity 17
The sprues and runners of the resin path 15 are separated from the first molded piece 7 and movable by a lock bin (not shown) provided on the movable mold 11 side when the mold is opened. Moves with the mold 11,
It is separated from the movable mold 11 near the mold opening and taken out.

The suction member 22 holding the first molded piece 7 by suction returns to the position where the first molded piece 7 does not come into contact with the fixed mold 10 by the forward movement of the reciprocating cylinder 25, and then the movable cylinder 2
3 moves to the insert position of the second cavity 18, and as the advance/retreat cylinder 25 retreats, the first
The molded piece 7 is inserted into the second cavity 18. In addition, at the insert position in the second cavity 18,
Adsorption means (not shown) using negative pressure is provided, and the first
Hold the molded piece 7 so that it does not move.

The suction member 22 returns to its original position by the advancement of the reciprocating cylinder 25 and the operation of the moving cylinder 23, resulting in the state shown in FIG. Then, the mold is closed (the state shown in FIG. 2), and the first molded piece 7 is again formed in the first cavity 17 in the same manner as described above.
At the same time, a second resin is injected from the second injection device 6 via the second resin path 16 into the second cavity 18 into which the previously molded first molded piece 7 is inserted. The second molded part 8 is filled and fused to the inserted first molded part 7.

After an appropriate cooling time, the mold is opened, and in the same manner as described above, the first molded piece 7 in the first cavity 17 is transferred to the second cavity 18 by the transfer means 20, and during this time, the movable A composite molded product 9 in which the first molded piece 7 and the second molded portion 8 which have been attached and moved to the mold 11 are joined is molded from the movable mold 11 (FIGS. 3 and 4).

After returning to the state shown in FIG. 1 again, the same cycle is repeated.

In this way, according to the invention, a composite molded article can be obtained in every I cycle without molding the first molded piece 7 and the second molded part 8 simultaneously.

Composite molded product 9, first molded piece 7, second molded part 8
The shape, number and arrangement thereof are not restricted to the above-mentioned embodiments, and can be freely selected and determined depending on the intended use.

For example, when manufacturing a magnetic tape case such as that shown in FIG. 8 (al), as shown in FIG. a first resin passage 15 that communicates with both cavities 17 and 17, and a second cavity 18 and a third cavity 31 that mold the front cover 29 and back cover 30, respectively.
and these second and third cavities 3
1, the second molded part 8 has two first molded pieces 7, 7.
A front cover and a back cover 30, which are composite molded products 9 joined together, can be obtained at the same time.

In addition, in the case of a large number of molded pieces, as shown in FIG.
, the first cavity 17, and the second cavity 18 in this order, the moving distance of the first molded piece 7 can be shortened.

In this case, it is better to adopt a three-plate mold structure or a one-net runner mold structure.

In any case, the number of heads of suction and gripping members for transferring the first molded pieces 7 to the second cavity 18 is the same as the number of first molded pieces 7.

Further, it is preferable that the first molded piece 7 and the second molded part 8 be joined with a step as shown in FIG.

As described above, according to the method and apparatus for manufacturing a synthetic resin composite molded product according to the present invention, a composite molded product in which different colored or different synthetic resin parts are joined and integrated can be continuously and efficiently manufactured in each cycle. In addition to this, it also has the following features:

Compared to the method of gluing after molding, no adhesive is required, and there is no problem of poor adhesion or adhesive extrusion. In addition, compared to the method of inserting pre-formed parts, the process is simpler, there is no need to store and manage the pre-formed parts to prevent damage, there is no need to align them for automatic inserting, and the relationship between the resin and insert parts during molding is reduced. There is less occurrence of cracks and stress due to temperature differences,
The adhesion condition also improves.

In addition, compared to the method of joining different types of resin by rotating two movable molds alternately, there is no need to move heavy molds with high accuracy every cycle, and to combine them alternately, and the total mold cost is cheaper. The molding cycle can also be made faster, and there is no need for a means to rotate the mold.

Furthermore, compared to a method in which the movable core protrudes within the mold to perform the first molding, the movable core is retracted, and the second molding is performed in the gap, the shape is not restricted and the molding cycle is shorter. It is much faster and no means are needed to move the moving core.

In this way, the two injection devices and the first molded piece are transferred to the second cavity using a general-purpose mold clamping mechanism that does not require a means for rotating the mold or a means for moving the movable core. Composite molded products can be efficiently molded by simply adding a lightweight transport means for the molding, the equipment is compact, the total mold cost is low, and control is easy.

Although the present invention has been variously explained above with reference to preferred embodiments, the present invention is not limited to these embodiments. Two molding machines are used, and one molding machine molds the first molded piece. Then, the second molding part is molded using the other molding machine,
A similar method can be achieved by synchronizing the opening and closing operations of both molding machines, or by inserting the first molded product into the second molded part and the second composite molded part into the third molded part. Of course, many modifications can be made without departing from the spirit of the invention, such as integrally molding a third composite molded product.

[Brief explanation of the drawing]

1 to 6 show embodiments of the device according to the present invention, and FIGS. 1 to 4 are cross-sectional views taken along line c-c' in FIG. 5 showing various operating modes, and FIG. 1, FIG. 6 is a sectional view taken along BB' in FIG. 2, and FIG. 7 shows an example of a joint between the first molded piece and the second molded part, Figure 8 shows an example of another composite molded product, +8) is a perspective view after assembly, (b
) is a cross-sectional view taken along the line DD' in FIG. Each figure is a schematic illustration of essential parts for explaining the present invention. DESCRIPTION OF SYMBOLS 1... Fixed plate, 2... Movable plate, 3... Tie bar, 4... Tip part, 5... First injection device, 6... Second injection device, 7...・First
molded piece, 8... second molded part. 9... Composite molded product, 10... Fixed mold. 11... Movable mold, 12... Nozzle introduction hole. 15... First resin path, 16... Second resin path, 17... First cavity, 1B... Second cavity, 20... Transfer means. 21... Frame, 22... Adsorption member. 23...Moving cylinder, 24...Moving piston, 25...Advancing/retracting cylinder, 26...Piston, 27...Guide bar, 29...
Front cover, 30...Back cover, 31...Third cavity 6

Claims (1)

[Claims] 1. A first molded piece molded with a first resin in a first cavity is inserted into a second cavity, and the second molded piece is molded with a first resin.
By molding the second molded part with the resin of
In a method for manufacturing a synthetic resin composite molded product in which a molded piece and a second molded part are integrally joined, the first molded piece and the second molded part are molded almost simultaneously at the time of mold closing, and the second molded part is molded almost simultaneously. A method for manufacturing a synthetic resin composite molded product, comprising repeating a cycle of removing the molded product from a cavity and inserting a first molded piece into a second cavity at the time of opening the mold. 2. A split mold whose split surfaces approach and separate to open and close the mold has a first cavity formed when the mold is closed, which is connected to the first resin path and for molding the first molded piece. , a second cavity is provided, which is connected to the second resin passage, for inserting the first molded piece to mold the second molded part, and when the mold is opened, the molded part is molded in the first cavity. 1. An apparatus for manufacturing a synthetic resin composite molded product, comprising means for transporting a first molded piece to an insert position in a second cavity.