JPH1086165A - Mold structure for press mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a lower mold from being damaged by precluding a movable block from inclining due to resin pressure and preventing the occurrence of flashes of a molded article. SOLUTION: A movable block 26 disposed in contact with an upper mold 21 for blocking the outer peripheral part of a cavity 25 defined by the upper and lower molds 21, 22 is installed in a vertically slidable manner in a close proximity of the outer peripheral part of a lower mold 22, then a guide pin 30 projecting above the upper surface of the movable block 26 is provided and a guide hole 31 is formed in the upper mold 21 for insertion of the guide pin 30, so that the guide pin 30 comes into the guide hole 31 so as to guide the lowering movement of the movable block 26 when the movable block 26 is pressed downward by the upper mold 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold structure for press molding for molding interior materials for automobiles and the like.

[0002]

2. Description of the Related Art Conventionally, a mold as shown in FIG. That is, this mold structure is composed of a pair of upper and lower molds 1 and 2, and mold surfaces 3 and 4 each having an uneven surface are formed.
The cavity 5 is thus formed.

[0003] On the outer periphery of the lower mold 2, an upper mold 1 is provided.
A movable block 6 that abuts the outer peripheral side of the cavity and closes the outer peripheral part of the cavity 5 is surrounded. This movable block 6
Is mounted on a bolster 8 by a support shaft 7 so that the periphery of the lower mold 2 can be slid vertically up and down, and is always pressed by the spring 9 toward the upper mold 1, and a part thereof is It protrudes from the mold surface 4 of the lower mold 2.

When a press-molded product is manufactured by the above-described mold structure, first, a molten resin 10 is supplied onto a lower mold 2 from a supply device (not shown) in a mold-open state shown in FIG. .

In this state, an elevating mechanism (not shown) of the mold clamping device is operated to lower the upper mold 1 to form a cavity 5 between the upper mold 1 and the lower mold 2, thereby forming a molten resin 10.
Is gradually crushed. At this time, the mold surface 3 of the upper mold 1
Is in contact with the movable block 6 to close the outer periphery of the cavity 5 together with the upper mold 1 to prevent the molten resin from leaking out of the cavity 5 to prevent the occurrence of burrs and the like of the press-molded product. (The state of FIG. 5B).

In this state, when the upper mold 1 is further lowered and the mold is further advanced, the movable block 6 is lowered against the spring 9 and the mold surface 4 of the lower mold 2 (the rear surface of the product in general). Surface) and the upper and lower dies 1, 2
Is completed, and a molded article 12 having a predetermined shape is formed in the cavity 5.

[0007]

The movable block 6 in the above-described press-molding mold structure has a structure in which the movable block 6 is moved downward by simply pressing the upper mold 1, so that the movable block 6 and the lower Since a gap of about 0.1 mm is usually provided between the mold 2 and the outer periphery thereof during sliding, as shown in FIG. When the resin pressure of the molten resin 10 reaches the outer peripheral portion of the cavity 5 earlier, the movable block 6 is pressed in the outer peripheral direction and tilted. As a result, it is considered that a gap is formed between the movable block 6 and the upper mold 1, the resin intrusion portion 10a is formed, and the resin enters as a burr.

[0008] Further, as shown in FIG.
Of the lower mold 2 due to the inclination of the lower mold 2
Is damaged, or it comes in line contact with the upper mold 1,
The sealing function may be reduced.

In view of such circumstances, the present invention is directed to a press mold for preventing a movable block from being tilted due to a resin pressure, thereby preventing burrs from occurring in a product and eliminating damage to a lower mold by the movable block. It is intended to provide a mold structure.

[0010]

According to a first aspect of the present invention, there is provided a mold structure according to the first aspect of the present invention, wherein a peripheral portion of a lower mold is disposed close to a lower mold among upper and lower molds. A movable block is disposed to be able to slide up and down and close the outer peripheral portion of the cavity formed by the upper and lower molds in contact with the upper mold, and one of the upper surface of the movable block or the upper mold and the other side. And a guide hole for inserting the guide pin is formed in the upper mold, and the guide pin enters the guide hole when the movable block is pressed and lowered by the upper mold. Thus, the movable block is guided to descend.

According to a second aspect of the present invention, of the upper and lower dies, the upper and lower dies are formed in contact with the upper dies so that the outer peripheral portion of the lower dies can be vertically slidably approached. A movable block for closing an outer peripheral portion of the cavity to be formed, a guide portion protruding from an upper surface of the movable block is formed, and an inner peripheral portion of the guide portion is slidably contacted with an outer peripheral portion of the upper mold, and the movable block When the movable block is pressed and lowered by the upper mold, the inner peripheral surface of the movable block slides on the outer peripheral portion of the lower mold to guide the downward movement of the movable block. And

Therefore, when the movable block is pressed and lowered by the upper mold, the guide pin enters the guide hole or the inner periphery of the guide portion slides on the outer periphery of the upper mold, and the inner periphery of the movable block moves. By sliding the outer periphery of the lower mold, it is guided and does not tilt even when the resin pressure of the molten resin is applied. As a result, it is possible to prevent the occurrence of burrs on the product and to make contact with the lower mold. Nothing.

[0013]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the present invention, wherein 21 is an upper mold, 22 is a lower mold, and the upper mold 21 is
The lower mold 22 is supported by a fixed bolster 28 so as to be vertically movable by a movable bolster (not shown). The upper and lower molds 21 and 22 are mutually connected to the mold surface 23,
24 are formed to form cavities 25.

A movable block 26 is provided on the periphery of the lower mold 22 so as to abut on the outer periphery of the mold surface 23 of the upper mold 21 to close the outer periphery of the cavity 25.

The movable block 26 is attached to a fixed bolster 28 by a support shaft 27 so that the movable block 26 can be slid close and vertically on the periphery of the lower mold 22, and is normally pressed by the spring 29 toward the upper mold 21. Thus, a part thereof projects from the mold surface 24 of the lower mold 22.

On the upper surface of the movable block 26, a steel guide pin 30 is projected and embedded, and the guide pin 30 is inserted into a guide hole 31 formed in the upper die 21. I have.

As shown in FIG. 2, the movable block 26 surrounds the outer periphery of the lower mold 22 so as to overlap the outer peripheral end line 32. For example, guide pins 30 are provided at six places. ing.

In FIG. 3, the width A of the movable block 26 is about 100 mm, the width B and the length C of the guide pin 30 are 50 to 80 mm, respectively, and the gap between the guide pin 30 and the guide hole 31 is: 0.01 to 0.05 mm, and the guide pin 30 is formed in a taper type taper at an angle D of 1 to 3 °.

When a press-molded product is manufactured in the above-described configuration, first, the molten resin 10 is supplied onto the lower mold 22 from a supply device (not shown) in a mold open state shown in FIG.

Then, from this state, an elevating mechanism (not shown) of the mold clamping device is operated to lower the upper mold 21 and
A cavity 25 is formed between the lower mold 22 and the molten resin 10 is gradually crushed. At this time, the upper mold 21
The peripheral portion of the mold surface 23 abuts on the movable block 26 to close the outer peripheral portion of the cavity 25 together with the upper mold 21, and the molten resin leaks out of the cavity 25 to generate burrs and the like of the press-molded product. (FIG. 1 (2)). In this process, the movable block 26 is held at a predetermined position without the guide pin 30 being inserted into the guide hole 31 and losing the resin pressure of the molten resin 10.

Further, when the upper mold 21 is lowered and the mold is further advanced, the movable block 26 is guided in parallel with the axial direction of the support shaft 27 by inserting the guide pin 30 into the guide hole 31. Descends against the spring 29,
It is pushed to the same level as the mold surface 24 of the lower mold 22 (general back surface of the product) to complete the clamping of the upper and lower molds 21 and 22, and the molded product 33 having a predetermined shape is formed in the cavity 25. It is molded (Fig. 1 (3)).

In this process, the movable block 26
The guide pin 30 is inserted into the guide hole 31 and the molten resin 1
The predetermined position is maintained without losing the resin pressure of 0.

As a result, the movable block 26 is
2 without forming a gap between them, and does not generate burrs on the product, does not come into contact with the lower mold 22, and does not damage the lower mold 22.

In the above embodiment, the guide pins 3
0 is provided on the upper surface of the movable block 26, and the guide hole 31 is provided on the upper mold 21 side. However, the present invention is not limited to this. It may be provided on the side.

FIG. 4 shows a second embodiment of the present invention, in which a guide portion 40 is provided instead of a guide pin, and the guide portion 40 is formed integrally with the movable block 36.
The inner peripheral portion 36a of the movable block 36 is in sliding contact with the outer peripheral portion 25a of the lower mold 25, and the inner peripheral portion 40a of the guide portion 40 is in sliding contact with the outer peripheral wall 21a of the upper mold 21 to slide as a guide portion. The peripheral portion of the cavity 25 is closed together with the mold 21, and the other configuration is the same as that of the first embodiment.

[0027]

As described above, according to the present invention, the outer peripheral portion of the cavity formed by the upper and lower dies is brought into contact with the upper die so that the peripheral portion of the lower die can be slid vertically. When a movable block to be closed is installed, when the movable block is pressed down by the upper mold, the guide pin enters the guide hole, or the inner periphery of the guide portion slides on the outer periphery of the upper mold. The inner periphery of the movable block is guided by sliding contact with the outer periphery of the lower mold, so that even if the resin pressure of the molten resin is applied, the movable block does not tilt. As a result, it is possible to prevent burrs from being generated on the product. Since there is no contact with the lower mold, the lower mold is not damaged by the movable block.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the present invention, in which (1) is a mold opening step, (2) is a temporary stopping step in which an upper mold is lowered to be placed at a mold clamping intermediate position, and (3) is a sectional view. 4 shows a mold clamping completion step.

FIG. 2 is a plan view of an upper mold in FIG.

FIG. 3 is an enlarged sectional view showing the vicinity of a movable block in FIG. 1;

FIG. 4 is a sectional view similar to FIG. 3, showing another embodiment.

FIG. 5 is a cross-sectional view showing a conventional mold for molding, and FIG.
Shows a mold opening step, (2) shows a temporary stopping step at the mold clamping intermediate position by lowering the upper mold, and (3) shows a mold clamping completion step.

FIG. 6 is a plan view of a lower mold in FIG. 5;

FIG. 7 is an enlarged sectional view showing the vicinity of a movable block in FIG. 5;

[Explanation of symbols]

 Reference Signs List 21 Upper die 22 Lower die 25 Cavity 26, 36 Movable block 27 Support shaft 29 Spring 30, 40 Guide pin 31 Guide hole

Claims (2)

[Claims] 1. An outer peripheral portion of a cavity formed by the upper and lower molds in contact with the upper mold so that the outer peripheral portion of the lower mold can be vertically slid close to each other. A movable block to be closed is provided, and one of the upper surface of the movable block and the upper mold is provided with a guide pin projecting to the other side, and the other side is formed with a guide hole through which the guide pin is inserted, The mold structure for press molding, wherein when the movable block is pressed down by the upper mold, the guide pin enters the guide hole to guide the descending movement of the movable block. 2. An outer peripheral portion of a cavity formed by the upper and lower molds in contact with the upper mold so that the outer peripheral portion of the lower mold can be slid vertically close to each other. A movable block to be closed is set up, a guide portion protruding from the upper surface of the movable block is formed, and an inner peripheral portion of the guide portion is slid in contact with an outer peripheral portion of the upper mold, so that an inner peripheral surface of the movable block is Combined with slidingly contacting the outer peripheral portion of the lower mold, when the movable block is pressed down by the upper mold, the movable block is guided to move downward. Mold structure.