JP2514984Y2 - Injection mold - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding die. More specifically, it relates to an injection molding die that moves a moving die along an inclined pin in an oblique direction that is inclined from the injection direction.

[0002]

2. Description of the Related Art Conventionally, a mold for injection molding is composed of a fixed mold and a movable mold, and a space equal to a molded product is formed between the fixed mold and the movable mold. . And
The injection molding die is used by injecting molten thermoplastic resin into the cavity of the injection molding die from the direction of the fixed die and filling the void with the thermoplastic resin. Among them, the thermoplastic resin is solidified to form a molded product, and then the moving mold is retracted to take out the molded product inside.

However, if the inner surface of the moving mold has a portion that widens toward the tip of the undercut portion, the moving mold cannot be retracted in the injection direction. Therefore, in an injection molding die having such an undercut portion, etc., a fixed die is provided with an inclined pin that is inclined outward from the injection direction, and a portion having this undercut portion is formed as another moving die, There is a method in which the inclined pin is inserted into a hole provided in the movable die and the movable die is moved in an oblique direction along the inclined pin.

For example, Japanese Examined Patent Publication (Kokoku) No. 52-43229 discloses an injection molding die having such an inclined pin. In the conventional die having such a tilting pin, the tilting pin uses a rod-shaped body having the same diameter from the portion attached to the fixed die to the tip.

[0005]

However, in such a mold, it is necessary to accurately match the angle of the hole provided in the movable mold with the angle of the inclined pin, but this is difficult in mold manufacturing, In some cases, the angle may be slightly different. As a result, there is a problem in that the moving mold does not fit exactly into the fixed mold.

Further, the movable mold is retracted in the injection direction to take out the molded product between the movable mold and the fixed mold. In the movable mold having the inclined pin, the movable mold moves with the movable mold plate. At the same time as the mold is retracted, the movable mold that moves diagonally is pulled, and the movable mold is moved along the inclined pin.
As described above, in the moving mold that moves in the tilt direction, the direction of the force that moves the moving mold does not match the direction that the tilt pin moves. Therefore, there is a problem that when the tilt pin moves in the hole of the movable die, a so-called “chattering phenomenon” occurs in which the tilt pin moves or stops, and the tilt pin is damaged.

Further, when the movable pin moves in the hole of the movable mold, the entire surface of the inclined pin inserted in the inner surface of the movable mold comes into contact with the surface of the hole, which causes a problem that the resistance is large. . Therefore, an object of the present invention is to provide a mold in which an inclined pin smoothly moves in a moving mold, a "chatter phenomenon" does not occur, and a moving resistance is small.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems and achieves the above object. The movable die is slanted from the injection direction along an inclined pin attached to a fixed die. In the injection molding die which is moved in the direction, the inclined pin is made thinner from the attachment portion to the tip.

[0009]

Since the tilt pin of the present invention is tapered toward the tip, even if the angle formed between the hole provided in the movable mold and the tilt pin is slightly different, the tilt pin must be within the narrow tilt range. For example, the moving mold fits perfectly in the fixed mold. In addition, since the inclined pin becomes thinner toward the tip in this way, a so-called "chatter phenomenon" also occurs when a movable die is moved, because a gap is formed between the hole of the movable die and the inclined pin. There is less resistance.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. The drawings show one embodiment of the present invention, in which 1 is a fixed mold and 2 is a movable mold which moves in the injection direction. Reference numeral 3 denotes a movable die that moves in an oblique direction that is inclined from the injection direction, and is slidably mounted on the surface of the movable die 2.

Reference numeral 4 denotes a mounting plate, and the mounting plate 4 is moved forward and backward in the injection direction by a driving device (not shown). Reference numeral 5 denotes an inclined pin, and this inclined pin 5 is fixed to the fixed mold 1. This inclined pin 5 is a fixed mold 1
It is made thinner from the attachment part attached to the tip to the tip, and is inserted into the hole provided in the moving mold 3.

Reference numeral 6 denotes a connecting plate, which is fixed to the mounting plate 4 and the moving mold 2. When the mounting plate 4 moves forward or backward, the moving mold 2 moves forward. It is designed to retreat. Further, when the movable die 2 moves forward or backward, the movable die 3 slidably mounted on the surface of the movable die 2 is also inclined together with the movable die 2 along the inclined pin 5 from the injection direction. Move forward or backward in the diagonal direction.

Reference numeral 51 is an extrusion pin, and this extrusion pin 51
Is moved forward by a driving device (not shown) to push out a molded product attached on the surface of the fixed mold 2. 7 is a nozzle insertion hole of the injection molding machine. 8 is a gap provided between the movable molds 2 and 3 and the fixed mold 1,
The shape of this gap 8 is the same as that of the molded product.

An undercut portion 9 is provided so as to project into the gap 8. Next, a method of using this injection molding die will be described. Assemble the injection mold as shown. The nozzle of the injection molding machine is inserted into the nozzle insertion hole 7, and the molten thermoplastic resin is injected into the gap 8 from here.

After the thermoplastic resin injected into the gap 8 is solidified, the mounting plate 4 is retracted in the injection direction. Then, the movable mold 2 is moved in the injection direction by the connecting plate 6 fixed to the mounting plate 4. At the same time, the moving mold 3
Is pulled in the injection direction in conjunction with the moving mold 2 and moves diagonally along the tilt pin 5. In this way, by moving the moving die 3 having the undercut portion in the oblique direction inclined from the injection direction, the moving die 3 having the undercut portion can be moved without damaging the molded product. .

Further, since the inclined pin 5 becomes thinner toward the tip, as the movable die 3 moves,
A gap is formed between the hole of the movable mold 3 and the inclined pin, so that the “chapping phenomenon” does not occur, and the resistance generated when the movable mold 3 moves is small and the movable mold 3 moves smoothly. After the movable molds 2 and 3 have retracted, the extrusion pin 51 moves forward to push out the molded product attached to the movable mold 2 and take out the molded product.

Next, when the mounting plate 4 is moved forward in the injection direction, the movable dies 2, 3 are moved in the opposite direction to when the mounting plate 4 is retracted.
Moves and the mold fits in its original condition. At this time, since the tip end portion of the tilt pin 5 is thin, even if the mounting angle of the tilt pin 5 and the hole provided in the movable die are slightly different, the tilt pin 5 will not move in the hole. Move and fit tightly in a fixed mold.

[0018]

As can be seen from the above description, since the inclined pin used in the injection molding die of the present invention becomes thinner toward the tip, the fixed angle of the inclined pin and the insertion of the movable die are slightly increased. Even if the angle of the hole is different, it will be firmly fitted and fixed in the fixed mold.

Further, when the tilt pin moves in the hole of the moving mold, a gap is created between the hole of the mold and the tilt pin, so that the "chatter phenomenon" does not occur, the resistance is reduced, and Less damage. As described above, the injection molding die of the present invention is extremely valuable.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of a mold of the present invention.

[Explanation of symbols]

1 Fixed mold 2 Moving mold 3 Moving mold that moves in an oblique direction inclined from the injection direction 4 Mounting plate 5 Inclined pin 9 Undercut part

Claims (1)

(57) [Scope of utility model registration request] 1. An injection molding die for moving a movable die along an inclined pin attached to a fixed die in an oblique direction inclined from an injection direction, wherein the inclined pin is tapered from an attachment portion to a tip thereof. A mold for injection molding characterized by being made.