JPH0318170Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention is an injection molding/vulcanizing device for rubber, particularly an injection molding/vulcanizing device that can vulcanize the rubber remaining on the sprue of a mold and easily take it out. Regarding.

[Conventional technology]

In conventional injection molding and vulcanization equipment, an upper mold fixed to a fixed plate and a lower mold fixed to a movable plate are placed facing each other, and the cavity of this mold directly communicates with the narrow gate part. The gate part further opens through the sprue part to the upper mold surface, and the fixed plate is provided with an injection nozzle insertion hole so that the injection nozzle of the injection machine can come into contact with this opening from the fixed plate side.

The rubber material press-fitted into the mold from the injection nozzle of the injection machine through the sprue section and the gate section fills not only the cavity but also the gate section and the sprue section. Then, after pulling back the plunger and lifting the injection nozzle away from the sprue,
A heating device provided integrally with the mold heats the rubber material in the cavity and sprue. However, the rubber material in the cavity is heated and vulcanized and hardened and expands, pushing up the rubber material in the gate and sprue parts, so that the rubber material backflows from the upper mold surface into the injection nozzle insertion hole of the fixed plate. It is unavoidable that some parts of the body bulge out.

With conventional equipment, it has not been possible to vulcanize the backflow rubber portion that bulges out from the surface of the upper mold as described above. When the movable plate is lowered to separate the lower mold from the upper mold in order to take out the molded product from the mold, the molded product is separated from the sprue at the gate, leaving vulcanized rubber on the sprue. The next injection will not be possible unless this residual rubber is removed from the sprue, but the backflow rubber that bulges out from the sprue is unvulcanized and uncured, so even if you try to grab the backflow rubber and pull it out, it will not stretch. It is impossible. Therefore, it was necessary to use a sharp awl or the like to pry out the remaining rubber. In this way, there is a problem in that removing the residual rubber from the sprue requires skill, takes a lot of time, and, of course, cannot be automatically removed using a device.

[Problem that the invention attempts to solve]

The present invention is a rubber that can easily vulcanize the backflow rubber part that bulges out from the sprue part during vulcanization, and can easily take out the residual rubber on the sprue part by grasping the vulcanized backflow rubber part. The purpose is to provide injection molding and vulcanization equipment.

[Means for solving problems]

The rubber injection molding/vulcanization apparatus of the present invention includes a mold having a gate part and a sprue part communicating with the cavity, and an insertion hole for the injection nozzle of the injection machine, and the insertion hole is connected to the sprue part of the mold. A metal fixing plate communicated with and fixed on the mold; and a metal fixing plate that is removably inserted into the injection nozzle insertion hole of the fixing plate and has a recess at a position facing the sprue of the upper mold when inserted. It is equipped with a cap.

The metal cap needs to be sufficiently heated by the heat applied to the mold for vulcanization.
It is preferable to use a metal with good thermal conductivity such as aluminum or copper.

[Effect]

The metal cap used in the present invention can be attached to and removed from the injection nozzle insertion hole of the fixed plate, and the cap and mold are normally used repeatedly in the vulcanization molding cycle. Therefore, when the cap is inserted into the injection nozzle insertion hole and the mold is heated with a vulcanization heating device, heat is transferred directly from the mold and from the fixed plate heated by heat transfer from the mold. The cap is always kept loose because it is heated by heat transfer. In each molding and vulcanization process, the injection nozzle is inserted through the injection nozzle insertion hole with the cap removed, pressed against the sprue entrance of the upper mold, and the rubber material is filled into the cavity. After rising away,
The warmed cap as described above is inserted into the injection nozzle insertion hole, and then vulcanization is performed as usual. The heat applied to the mold during vulcanization is transferred from the upper mold and the heated fixed plate to the cap by heat transfer from the upper mold, and the cap is heated to approximately the same temperature as the mold during vulcanization. On the other hand, the backflow rubber portion bulged from the sprue portion during vulcanization enters the recessed portion of the cap, and is completely vulcanized and hardened by the radiant or conductive heat from the warmed cap as described above. Therefore, after vulcanization, remove the cap and
When the mold is disassembled to take out the vulcanized molded product, the residual rubber on the sprue portion can be easily and completely removed by manually or mechanically grasping and pulling up the cured backflow rubber portion.

〔Example〕

An embodiment of the device of the present invention will be described with reference to the drawings.

A mold having a cavity 5 corresponding to the shape of the molded product is divided into an upper mold 1 and a lower mold 2, and the upper mold 1 is mounted on a fixed plate 3 fixed by a support or a side frame (not shown) or the like. The lower die 2 is attached to a movable plate 4 fixed to a ram (not shown) of a hydraulic press or the like. The upper mold 1 has a gate part 6 and a gate part 6 that directly communicate with the cavity 5.
It is equipped with a sprue section 7 that communicates with the. The fixing plate 3 fixing the upper mold 1 is made of metal so as to be heated by the heat transmitted from the upper mold 1, and has an insertion hole 8 for an injection nozzle of an injection machine (not shown). The sprue portion 7 of the upper die 1 opens into the injection nozzle insertion hole 8 . Furthermore, the aluminum cap 9 is inserted into the injection nozzle insertion hole 8 of the fixed plate 3.
The cap 9 is provided with a recess 10 at a position facing the sprue portion 7 of the upper mold 1 when the cap 9 is inserted.

When injecting the rubber 11, remove the cap 9,
An injection nozzle (not shown) is inserted into the insertion hole 8.
The rubber 11 press-fitted into the mold from the injection nozzle is filled into the cavity 5, the gate part 6, and the sprue part 7 as shown in the figure. When this rubber 11 is heated and vulcanized, the concave part 10 of the cap 9 extends from the sprue part 7.
It bulges inward as a backflow rubber part 12,
Since the cap 9 is inserted into the injection nozzle insertion hole 8 before proceeding to the vulcanization process, the backflow rubber portion 12 bulging from the sprue portion 7 is inserted into the recess 10 of the cap 9.
As a result, this backflow rubber part 12 is also vulcanized by the heat transmitted from the upper die 1 and the fixing plate 3 to the cap 9 together with the rubber 11 in the cavity 5, gate part 6, and sprue part 7. be done. The vulcanized backflow rubber part 12 is sufficiently hardened, so after removing the cap 9, it is grasped manually or with a clamp such as an automatic hand, and is held together with the rubber of the sprue part 7 and possibly the gate part 6. can be easily eliminated.

[Effect of idea]

According to the present invention, the backflow rubber part that bulges out from the sprue part during vulcanization can be vulcanized and hardened, so when removing the vulcanized residual rubber in the sprue part when taking out the vulcanized molded product. , the cured backflow rubber part can be easily and completely removed by grasping it, and the remaining rubber can be automatically removed using a device such as an autohand, which eliminates the need for human labor, so it has great industrial utility value. It is.

[Brief explanation of drawings]

The drawing is a schematic cross-sectional view of the device of the present invention. 1...Upper mold, 2...Lower mold, 3...Fixing plate, 5...Cavity, 6...Gate part, 7...
Sprue portion, 8... Injection nozzle insertion hole, 9... Cap, 10... Recessed portion, 12... Backflow rubber portion.

Claims (1)

[Scope of utility model registration request] A heating mold having a gate part and a sprue part communicating with the cavity, and an insertion hole for an injection nozzle of an injection machine, the insertion hole communicating with the sprue part of the mold, and fixed on the mold. The invention is characterized by comprising a metal fixing plate, and a metal cap that is removably fitted into the injection nozzle insertion hole of the fixing plate and has a recess at a position facing the sprue part of the upper mold when it is fitted. Rubber injection molding vulcanization equipment.