JPH0880548A - Injection mold - Google Patents

Abstract

PURPOSE: To provide an injection mold designed to prevent the scuffing or damaging of a cam shaft and can groove caused through vibration during the mold opening and closing period. CONSTITUTION: A stationary mold plate 1 has a cam shaft 3 supportingly provided by a spring and, besides, has a cam shaft block 2 with a tapered surface 2a provided in a fixed manner, and further a movable mold plate 6 has a sliding block 7 with a tapered surface 7a and a rocking block 8 with a can groove 12 provided thereon, wherein the sliding block 7 is provided in such a manner that it is movable in the direction normal to the opening and closing direction of the mold. The tapered surface 2a of the cam shaft block 2 and the tapered surface 7a of the sliding block 7 are at the same angle with respect to the opening and closing direction of the mold, and through the opening and closing operation of the mold, the cam shaft 3 is moved along the cam groove 12, and the tapered surface 2a of the cam shaft block 2 is placed in contact with the tapered surface 7a of the sliding block 7, in order to slide the sliding block 7 in the direction normal to the opening and closing direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection mold, and more particularly to a mold for injection molding a molded article having an undercut portion.

[0002]

2. Description of the Related Art Some injection-molded products have a shape having a biting portion (called an undercut) in which the molded product cannot be taken out only by moving the mold in the opening / closing direction. A slide block mold is a mold for injection-molding a molded product having this undercut portion. In this slide block mold, a movable part (slide block) that is movable in a direction perpendicular to the opening / closing direction of the mold is provided. The conventional slide block mold has a fixed mold plate 2 as shown in FIG.
1, a movable mold plate 22, a cam groove plate 23 fixed to the fixed mold plate 21, and a slide block 24 that slides on the movable mold plate 22 in a direction perpendicular to the opening / closing direction of the mold. The slide block 24 has a cam shaft 25.
Is attached. 5 (a) and 5 (b) are diagrams showing the mold in a closed state and an open state, respectively. When the movable mold plate 22 is moved downward from the state of FIG. 5 (a) to open the mold, the cam shaft 25 is guided to the cam groove 26 of the cam groove plate 23 and moves to the lower left.
4 moves leftward on the movable mold plate 22 to be in the state shown in FIG. 5 (b). 27 is a bolt for fixing the fixed mold plate 21 and the cam groove plate 23.

[0003]

However, the slide block mold described above has the following problems.
That is, since the cam shaft 25 is fixed to the slide block 24, when a slight displacement of the mounting position occurs between the fixed side and the movable side due to vibration when the mold is opened and closed, the cam shaft 2
5 may bite the cam groove 26 or damage the cam groove plate 23.

[0004]

SUMMARY OF THE INVENTION The present invention provides an injection molding die that solves the above-mentioned problems.
A movable mold plate having a slide block, and the movable mold plate is moved relative to the fixed mold plate to open and close the mold, so that the slide block is perpendicular to the opening and closing direction of the mold. In an injection molding die that slides in the direction of, a fixed mold plate is provided with a cam shaft supported by a spring,
Further, a cam shaft block having a taper surface is provided so as to be fixed, a slide block having a taper surface and a locking block having a cam groove are provided on the movable mold plate, and the slide block is in a direction perpendicular to the opening / closing direction of the mold. The taper surface of the cam shaft block and the taper surface of the slide block make the same angle with respect to the opening and closing direction of the mold.By opening and closing the mold, the cam shaft is moved along the cam groove. It is characterized in that the taper surface of the cam shaft block is moved to abut the taper surface of the slide block, and the slide block is slid in a direction perpendicular to the opening / closing direction.

[0005]

As described above, the cam shaft is supported by the spring on the cam shaft block provided on the fixed mold plate, and the cam shaft is guided by the cam groove of the locking block provided on the movable mold plate. Then, since the cam shaft is supported by the spring, a little play occurs in the movement of the cam shaft, the cam shaft moves smoothly along the cam groove, and damage to the cam shaft and the cam groove can be prevented. Also, since the taper surface of the cam shaft block and the taper surface of the slide block form the same angle with respect to the opening and closing direction of the mold, the taper surface of the cam shaft block surely comes into surface contact with the taper surface of the slide block. Thus, the slide block can be moved in the direction perpendicular to the opening / closing direction.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in the drawings. 1 (a) and 1 (b) are a partial side view and a front view of a fixed mold plate of an embodiment of an injection molding die according to the present invention. As shown in FIG. 1, a fixed mold plate 1 is provided with a camshaft block 2 having a tapered surface 2a, and in the camshaft block 2, a camshaft 3 and two springs 4 are provided.
It is pressed and held by. The end of the spring 4 is fastened with a stop bolt 5.

FIG. 2 is a partial plan view of the movable die plate side of this embodiment. A slide block 7 having a taper surface 7a is slidably attached to the movable template 6 by being biased to the right by a spring 9. Reference numeral 11 is a stop bolt that stops the slide block 7 against the spring 9. A locking block 8 having a cam groove 12 is fixedly attached to the movable mold plate 6. The cam groove 12 is provided so as to have a wall surface 12a parallel to the opening / closing direction of the mold. Further, the tapered surfaces 2a and 7a form the same angle with respect to the opening / closing direction of the mold. 10
Is a movable core block.

3 and 4 are front views of the mold in an open state and a closed state, respectively. FIG.
As shown in (a), the inner side of the bottom of the camshaft block 2 is seated, so when the movable mold plate 6 is moved upward and the mold is closed, the cam groove 12 is positioned inside the camshaft block 2. The cam shaft 3 and the cam groove 12 are engaged with each other. Further, since the taper surface 2a of the cam shaft block 2 forms the same angle as the taper surface 7a of the slide block 7 with respect to the opening / closing direction of the mold, when the mold is closed, the taper surface 2a of the cam shaft block 2 is formed. The surface 2a and the taper surface 7a of the slide block 7 are surely brought into surface contact with each other. Therefore, when the movable die plate 6 is moved upward to close the die, the cam shaft 3 enters the inside of the cam groove 12 along the cam groove 12, and the taper surface 2a of the cam shaft block 2 becomes the spring 9. Push the slide block 7 to the left against it. Then, the slide block 7 moves leftward, fits with the movable core block 10, and the mold clamping is completed. On the other hand, when the mold is opened, the cam shaft 3 moves above the cam groove 12, the slide block 7 is biased by the spring 9 and moves to the right, and finally returns to the position of the stop bolt 11. In this embodiment, since the cam shaft 3 is pressed and held by the springs 4 from both sides, a slight play occurs in the movement of the cam shaft 3, and the cam shaft 3 moves smoothly along the cam groove 12.

[0009]

As described above, according to the present invention, a fixed mold plate is provided with a cam shaft supported by a spring, and a cam shaft block having a tapered surface is provided so as to be fixed, and a movable mold plate is provided. Is provided with a slide block having a tapered surface and a locking block having a cam groove, and the slide block is slidably provided in a direction perpendicular to the opening / closing direction of the mold, and the taper surface of the cam shaft block and the taper surface of the slide block are provided. Have the same angle with respect to the opening and closing direction of the mold.By opening and closing the mold, the cam shaft is moved along the cam groove and the tapered surface of the cam shaft block is brought into contact with the tapered surface of the slide block. As the slide block slides in the direction perpendicular to the opening / closing direction, a little play occurs in the movement of the cam shaft, and the cam shaft moves smoothly along the cam groove.
It is possible to prevent damage to the cam shaft and cam groove, and the taper surface of the cam shaft block surely comes into surface contact with the taper surface of the slide block to move the slide block in the direction perpendicular to the opening / closing direction. There is an effect.

[Brief description of drawings]

1A and 1B are a partial side view and a front view of a fixed mold plate of an embodiment of an injection molding die according to the present invention.

FIG. 2 is a partial plan view of the movable mold plate side of the above embodiment.

FIG. 3 is a front view showing a state in which the mold is open in the above embodiment.

FIG. 4 is a front view showing a state where the mold is closed in the above embodiment.

5A and 5B are explanatory views of a conventional mold in a closed state and an open state, respectively.

[Explanation of symbols]

 1 Fixed mold plate 2 Cam shaft block 2a, 7a Tapered surface 3 Cam shaft 4, 9 Spring 5 Fixing bolt 6 Movable mold plate 7 Slide block 8 Locking block 10 Movable core block 11 Stop bolt 12 Cam groove 12a Wall surface

Claims (1)

[Claims] 1. A fixed mold plate and a movable mold plate having a slide block are provided, wherein the movable mold plate is moved relative to the fixed mold plate to open and close the mold, In an injection molding die in which a slide block is slid in a direction perpendicular to the opening / closing direction of the die, a fixed mold plate is provided with a cam shaft supported by a spring, and a cam shaft block having a tapered surface is fixed. The slide block having a tapered surface and the locking block having a cam groove are provided on the movable die plate, and the slide block is provided slidably in the direction perpendicular to the opening / closing direction of the die, and the taper surface of the cam shaft block is provided. The taper surface of the slide block and the slide block make the same angle with respect to the opening and closing direction of the mold, and by opening and closing the mold, the cam shaft is moved along the cam groove, and the taper surface of the cam shaft block A die for injection molding, wherein the slide block is slid in a direction perpendicular to the opening / closing direction by bringing the slide block into contact with the tapered surface of the slide block.