JPH0557731A - Mold device for molding resin - Google Patents

Abstract

PURPOSE:To provide the above mold device for forming or pulling out the undercut part of a molded product on a cavity side by utilizing the opening and closing operations of a mold. CONSTITUTION:A mold device is equipped with a slide block 3 having a contour part 3b for forming the hole shape 1a being the undercut part of a molded product 1, an energizing means for energizing the slide block 3 in a direction wherein the contour part 3b is pulled out of the undercut part at the time of mold opening and a return means for sliding and returning the slide block 3 against energizing force at the time of mold closing and, since the undercut part of the molded product 1 on a cavity side can be pulled out in synchronous relation to mold opening, this mold device is extremely convenient in the shortening of a molding cycle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold device for removing an undercut on a cavity side of a molded product.

[0002]

2. Description of the Related Art A conventional resin molding die apparatus of this type has a structure shown in FIGS.

In FIG. 4, reference numeral 9 is a molded product having a hole 9a which is an undercut on the side surface. FIG. 3 shows a mold device for molding the molded product 9 shown in FIG. Reference numeral 10 denotes a slide insert having an undercut portion, which is arranged in the cavity template 11. Reference numeral 12 denotes a cylinder, which is connected to the sliding insert 10 and fixed to the end surface of the cavity template 11.

The operation of the mold apparatus having the above structure will be described below. First, after the resin is filled, the sliding insert 10 is retracted by the cylinder 12 before the mold is opened, the undercut of the molded product 9 is removed, the mold is opened, and then the mold is released.

[0005]

However, in the above-mentioned structure, the cylinder insert time must be removed by sliding the sliding insert by the cylinder before opening the mold, which requires cylinder driving time. There is a problem that the molding cycle becomes long.

In view of the above problems, therefore, the present invention can form a molded product having a hole shape that is undercut in conjunction with the mold opening operation without using a cylinder as in the conventional example, and Provided is a mold device capable of shortening a molding cycle.

[0007]

In order to solve the above problems, a molding die apparatus of the present invention is a slide block having a shape portion for forming an undercut portion of a molded product, and a mold for the slide block. An urging means for urging the shape part from the undercut portion when opening, a stopper for stopping the slide block slid for a certain distance by the urging force of the urging means, and the slide block when the mold is closed. And a returning means for slidingly returning the member against the biasing force.

[0008]

The present invention has the above-mentioned structure and is synchronized with the mold opening.
The biasing means causes the slide block to slide in the direction of removing the undercut, and the undercut on the cavity side of the molded product can be removed, which is extremely advantageous in shortening the molding cycle.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A resin molding die apparatus according to an embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a molded product having an undercut hole 1a on the cavity side, 2 is a rod having a surface inclined at an angle with respect to the mold opening direction at one end, and the fixed side mounting plate 7 at the other end. It is fixed to. 3 is the rod 2
A slide block having a contact surface 3a and a shape portion 3b formed at one end for forming an undercut portion of the hole shape 1a, which is slidable in the undercut removal direction.
Reference numeral 4 denotes a rod arranged in the sliding direction of the slide block 3, one end of which is fixed to the slide block 3. Reference numeral 5 is a spring and is arranged on the outer circumference of the rod 4.
A stopper 6 is fixed to the lower end of the fixed-side template 8 and stops the slide block 3 after sliding for a certain distance, and has a contact surface 6a of the spring 5.

The operation of the resin molding die device constructed as above will be described. FIG. 2 shows a molding die device when the mold is opened. By the mold opening, the rod 2 fixed to the fixed side mounting plate 7 is separated from the contact surface 3a of the slide block 3, and the spring 5 is guided inside the rod 4 to urge the rod 4 in the undercut extracting direction. The slide block 3 fixed to the rod 4 is stopped by the stopper 6 after sliding for a certain distance. By this operation, the hole-shaped undercut on the cavity side of the molded product 1 is removed and the molded product 1 is released from the mold. When the mold is closed, the contact surface 3a of the slide block 3 is urged by the rod 2 fixed to the fixed side mounting plate 7 to return the slide block 3 to the position before the mold is opened (the state of FIG. 1).

With the resin molding die apparatus of the present embodiment, there is no delay in the molding cycle due to the cylinder operation,
The molding cycle can be shortened.

[0013]

As described above, according to the present invention, there is no delay in the molding cycle due to the cylinder operation, the molding cycle can be shortened, the cylinder is not used, the molding cycle can be shortened, and the cost of the molded product can be reduced. Can be achieved.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a resin molding die device according to an embodiment of the present invention when a mold is closed.

FIG. 2 is a partial sectional view of the same resin molding die device when the mold is opened.

FIG. 3 is a partial sectional view of a conventional resin molding die device when the mold is closed.

FIG. 4 is a perspective view of a molded product having an undercut hole shape.

[Explanation of symbols]

 1 Molded product 1a Hole shape 2 Rod 3 Slide block 4 Rod 5 Spring 6 Stopper 7 Fixed side mounting plate 8 Fixed side template

Claims (1)

[Claims] 1. A slide block having a shaped portion for forming an undercut portion of a molded product, and a biasing means for biasing the slide block in a direction in which the shaped portion comes out of the undercut portion when a mold is opened. A stopper portion for stopping the slide block slid by a certain distance by the biasing means, and a return means for slidingly returning the slide block against the biasing force in the mold closing portion. Molding device for resin molding.