JPH08281708A - Injection mold - Google Patents

Abstract

PURPOSE: To provide an injection mold which has a support block having a large contact area with a movable side mold plate, prevents the strain of the plate and in which no flash is generated near a gate and at a product, and which obtains a molding having excellent quality. CONSTITUTION: An injection mold comprises ejector pins 5 to a cavity 4 formed of a fixed side mold plate 1 and a movable side mold plate 2, and a center ejection pin 9 provided to a resin reservoir 8 communicating with the sprue 7 of the side of the cavity 4 and passing the plate 2 in which the rear end of the plate 2 is fixed to an ejector plate 6, wherein a support block 10 is provided between the plate 2 and a movable side mold plate mounting plate 2a, the pin 9 is inserted into the hollow part 10 provided in the block 10, and its rear end is fixed to an ejector plate 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection mold provided with a plurality of protruding pins.

[0002]

2. Description of the Related Art Conventionally, in order to release a molded product molded in a cavity from a mold, a projection pin is generally provided on the movable mold plate side of an injection molding mold, and this projection pin is used when the mold is opened. The molded product is projected and released from the mold (see Japanese Patent Laid-Open No. 1-68815).

This structure will be described in detail with reference to FIG. 2 in detail. A conventional injection molding die is provided with a stationary mold plate 100, a movable mold plate 200, and the movable mold plate 200. Multiple core cavities 400, 4
00 is provided and configured to move the movable side mold plate 2 in order to release the molded product molded in the cavity 400.
00 and the core block 300, and the cavity 4
The protruding pins 500 up to 00 are provided,
Further, at the center of the movable side mold plate 200, a protruding pin 700 reaching the resin reservoir 700 at the tip of the sprue 600 is provided fixed to the protruding plate 800 at the rear end together with the protruding pins 500, 500. When the mold is opened, the protrusions are protruded from the front ends of the protrusion pins so that the molded product in the cavity 400 is protruded and released.

However, in the structure of the conventional injection molding die as described above, if the movable side mold plate 200 is designed to be thin, the movable side mold plate 200 is not closed when the mold is closed and the molten resin is injected. There is a problem that distortion occurs, burrs occur near the gate and the product part, and if the movable side mold plate is thickened to solve this problem, the mold itself becomes large and the productivity deteriorates. It occurs separately.

In order to solve this problem, as shown in FIG. 3, support blocks 900, 900 are provided between the movable side mold plate mounting plate 201 and the movable side mold plate 200 at the rear end of the projecting plate 800. It has been devised to suppress distortion that occurs when the mold plate 200 is closed and when the molten resin is injected.

[0006]

However, the support blocks 900, 900 have the protruding pins 500, 50.
Since the contact area to the movable-side mold plate 200 is not large due to the attempt to fit in the space between 0 and 700, a large pressing force generated when the mold is closed and when the molten resin is injected is supported. In some cases, it may not be cut, and there is still a concern that the movable-side template 200 may be distorted.

The present invention has been made in view of the above problems, and an object of the present invention is to solve these problems and to provide a large contact area with the movable side mold plate. (EN) Provided is an injection molding die which is provided with a support block, prevents distortion of a movable side mold plate, does not generate burrs near a gate or a product part, and can obtain an injection-molded product of excellent quality.

[0008]

In the injection molding die of the present invention, a protruding pin reaching a cavity formed by a fixed-side mold plate and a movable-side mold plate is further communicated with a sprue on the side of the cavity. In the injection molding die in which the center projecting pin reaching the resin reservoir penetrates the movable side template and the rear end is fixed to the projecting plate, the support block connects the movable side template and the movable side template mounting plate. The center protruding pin is inserted into a hollow portion provided in the support block, and the rear end of the center protruding pin is fixed to the protruding plate.

[0009]

In the injection molding die of the present invention, the projecting pin reaching the cavity formed by the fixed side mold plate and the movable side mold plate, and the center protrusion reaching the resin reservoir communicated with the sprue on the side of the cavity. In the injection molding die in which the pin and the movable side mold plate penetrate and the rear end is fixed to the projecting plate, a support block is provided between the movable side mold plate and the movable side mold plate mounting plate. Since the center projecting pin is inserted into the hollow portion provided in the support block and the rear end is fixed to the projecting plate, a supporting block having a large contact area with the movable side mold plate is provided, so that a large stress is exerted. Therefore, it is possible to prevent distortion of the movable-side mold plate, prevent burrs from being generated near the gate and the product part, and obtain an injection-molded product of excellent quality. In addition, the thickness of the movable side mold plate can be reduced, the mold can be downsized, and the manufacturing cost can be reduced, which is an economic effect.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of the injection mold of the present invention, showing a mold closed state. In the injection molding die shown in FIG. 1, a plurality of fixed side mold plates 1 fixed to a fixed mold plate mounting plate 1a, a movable mold plate 2 and core blocks 3 provided on the movable mold plate 2 are used. Cavity 4,
4 is provided and configured.

The injection mold 10 has a movable mold plate 2 for releasing the molded product molded in the cavity 4.
Further, projecting pins 5 and 5 penetrating the core block 3 and reaching the cavity 4 are provided, and the rear ends of the projecting pins 5 and 5 are fixed to a projecting plate 6 provided at the rear side.

Further, a center projecting pin 9 reaching a resin reservoir 8 provided on a parting surface of the fixed side mold plate 1 and the movable side mold plate 2 at the tip of a sprue 7 provided at the center of the fixed side mold plate 1. Are inserted into the movable-side template 2 and provided.

Reference numeral 10 denotes a support block, which is fixedly provided between the movable side mold plate 2 and the movable side mold plate mounting plate 2a. This support block 10
A hollow portion 10a is provided in the interior of the support block 1 and the rear of the center projecting pin 9 is inserted therethrough.
The rear end of 0 is fixed to a projecting plate 11 provided separately from the projecting plate 6.

A spring 12 is inserted through the hollow portion 10a of the support block 10 for the projecting pin 9 so that the projecting pin 9 is constantly pressed against the resin reservoir 8 when the mold is closed, so that the molten resin When the mold is opened, the center projecting pin 9 is advanced by the projecting plate 11 against the reaction force of the spring 12, and the molded product in the cavity 4 is opposed. It is designed to cooperate with mold release.

Therefore, by incorporating the center projecting pin 9 in the hollow portion 10a inside the support block 10, a space is generated around the support block 10, and the contact area of the support block 10 with the movable mold plate 2 is increased. It has become possible to provide a large.

As a result, unlike the conventional support block having a small contact area, the support block 10 ensures a sufficient resistance against the resin pressure at the time of injection of the molten resin and the mold clamping pressure to move the resin. Since the side template 2 can be supported, the occurrence of distortion of the movable template 2 can be prevented.

[0017]

In the injection molding die of the present invention, the protruding pin reaching the cavity formed by the fixed side mold plate and the movable side mold plate, and further reaching the resin reservoir communicated with the sprue on the side of the cavity. In an injection molding die in which a center projecting pin penetrates the movable side template and a rear end of the movable plate is fixed to the projecting plate, a support block is provided between the movable side template and the movable side template mounting plate. , The center protruding pin is inserted into the hollow portion provided in the support block,
Since the rear end is fixed to the projecting plate, a support block with a large contact area with the movable side mold plate is provided, so it is possible to withstand large stress and prevent the movable side mold plate from being distorted. As a result, burrs do not occur near the gate or in the product part, and an injection-molded product with excellent quality can be obtained. In addition, the thickness of the movable side mold plate can be reduced, the mold can be downsized, and the manufacturing cost can be reduced, which is an economic effect. Therefore, it is preferably used as an injection mold.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of an injection molding die of the present invention.

FIG. 2 is a sectional view showing an example of a conventional injection molding die.

FIG. 3 is a cross-sectional view showing an example of a conventional injection molding die.

[Explanation of symbols]

 1 Fixed-side mold plate 1a Fixed-side mold plate mounting plate 2 Movable-side mold plate 2a Movable-side mold plate mounting plate 3 Core block 4 Cavity 5 Projection pin 6, 11 Projection plate 7 Sprue 8 Resin reservoir 9 Center projection pin 10 Support block 10a Hollow part 12 Spring

Claims (1)

[Claims] 1. A projecting pin reaching a cavity formed by a fixed mold plate and a movable mold plate, and a center projecting pin reaching a resin reservoir communicated with a sprue on the cavity side penetrates the movable mold plate. In the injection molding die whose rear end is fixed to the projecting plate, the support block is provided between the movable side mold plate and the movable side mold plate mounting plate, and the inside of the hollow portion provided in this support block An injection molding die, wherein the center projecting pin is inserted into the and the rear end is fixed to the projecting plate.