JP2718942B2 - Mold for resin molding - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a mold apparatus for opening a cavity line later in a sleep-rate type resin molding die.

[Prior Art] For example, a sleep rate type provided with a pinpoint gate includes a movable plate, a fixed plate, and a runner plate. At the start of this type of sleep rate type mold opening, the fixed mold plate and the movable mold plate are locked, and the fixed mold plate and the runner plate are opened first, so that the runner is more protruded than the molded product protrusion. A mechanism that protrudes first is adopted. For example,
"Easy Plastic Mold" (Showa 58 published by Sanko Publishing Company)
As disclosed in the third edition, p. 71, July 30, 2003, a spring-loaded catch is provided on the outside of the movable mold plate, and a locker that enters the catch into the fixed mold plate and a lock sleeve inside the locker are provided. The mechanism to provide is adopted.

At the time of locking, the locker enters the claw in the catch, the lower end of the locker pushes down the claw cam of the catch to close the claw, and furthermore, the lock sleeve enters the claw cam to fix the claw.

When releasing the lock, the shoulder at the lower end of the release pin pulls up the lock sleeve and releases the lock sleeve from the claw cam of the catch.

[Problem to be Solved by the Invention] Since the cam lock means as described above is provided on one side outside the fixed mold plate and the movable mold plate, the robot is taken out from the upper or other parting line and the robot is formed by traveling. In order to take out the product and drop the runner downward, the mold must be used in at least two or three directions. Considering temperature control piping and the like, a mold having a small projected area is a significant positional constraint.

In addition, since the cam lock mechanism is used, each member must be attached to each mold plate after the mold opening / closing stroke is determined, and the attachment and stroke adjustment operations are troublesome. In addition, the cam lock mechanism becomes complicated, the number of parts is increased, and the cost is increased.

Thus, the present invention has been developed to solve the above-mentioned drawbacks, and can be attached to various dies by using existing sliding pins, and has the simplest mold opening sequence mechanism. The purpose is to provide.

[Means for Solving the Problems] The present invention for solving the above-mentioned object comprises a movable mold plate, a fixed mold plate and a separable plate, and when opening the mold, any one of the mold plates and the plate is first used. The present invention relates to the resin molding die to be opened.

The feature is that a sealing part is provided at the tip of the sliding hole of the sliding pin between the fixed mold plate and the movable mold plate, and the sliding pin advances to exhaust the inside of the sliding hole when the mold is closed. In addition, an air lock portion is provided to lock the fixed mold plate and the movable mold plate by setting the inside of the sliding hole to a negative pressure state at the start of mold opening.

[Operation] When the mold is closed, the air pressure in the sliding hole is increased by advancing the sliding pin, so that the air lock portion is released and air is discharged from the inside of the sliding hole to the outside. The sliding pin penetrates deeply into the sliding hole at its forward limit, and in this state, the fixed mold plate and the movable mold plate are in the mold closed position.

At the start of mold opening after resin molding, the mold opening force is applied to each mating surface of the separable plate, fixed mold plate and movable mold plate. When the parting line between the fixed mold plate and the movable mold plate is about to open, the air lock section works when the sliding pin tries to retreat in the sliding hole. Accordingly, the mating surface between the other plate and one of the templates is first opened. By receiving the full mold opening force at the mold opening limit, the fixed mold plate and the movable mold plate are opened against the airlock portion.

[Embodiment of the Invention] FIGS. 1 to 4 show one embodiment of the present invention, and illustrate a pinpoint gate type as an injection mold.

In the figure, 1 is a runner plate as another separable plate, 2 is a fixed mold plate, 3 is a movable mold plate, 4 is a fixed mounting plate, 5 is a spacer block, 6 is a movable mounting plate, and 7 is an ejector plate. , 8 are ejector pins and 9 is a support pin, and these form a typical sleep rate type resin molding die. 10 is a sprue, 11 is a runner part, 12 is a pinpoint gate, 13 is a cavity, 14 is a mating surface of the runner plate 1, 15 is a mating surface of the fixed mold plate 2 on the runner plate side, and 16 is a fixed mold plate 2 , And such a configuration is known.

Thus, this embodiment is characterized in that the fixed mold plate 2 and the movable mold plate 3
A guide pin 20 is provided as a sliding pin between the sealing member 22 and a sealing portion 22 is provided at the tip 21a of the sliding hole 21, and an air lock portion 23 is provided in the sealing portion 22. The sliding hole 21 can be formed in the guide bush 24, and can be put to practical use in a sealed structure in which a lid 22 as a sealed portion is fitted to a step 25 provided at the end thereof.

The air lock 23 forms a through hole 26 penetrating into the sliding hole, and forms a tapered conical lock receiving surface portion 27 on the sliding hole side of the through hole 26, and at the same time, forms the through hole.
The lock piece 28 is urged toward the sliding hole 26.
The lock piece 28 protrudes in a tapered conical shape, and
A lock surface portion 29 that is in close contact with 27, an air receiving surface portion 30 at the tip of the lock surface portion, and a reduced diameter portion 31 in the latter half are provided. A spring 32 is wound around the reduced diameter portion 31. Note that the spring 32 only needs to be able to prevent the spring 32 from jumping out by caulking the outside of the through-hole 26, but the stopper plate 33 can be stopped by a screw 34 as shown in the figure.

Further, an air escape groove 35 can be communicated between the guide bush 24 and the mating surface 15 of the fixed mold plate 2. Further, an O-ring 36 can be wound around the guide pin 20. The operation based on the above configuration will be described.

As the movable mold plate 3 is closed with respect to the fixed mold plate 2, the guide pin 20 advances through the slide hole 21 to increase the air pressure in the slide hole. This air pressure is
When the lock piece 28 is retracted against the spring 32, the air is discharged from the gap between the lock receiving surface 27 and the lock surface 29.

At the end of the air discharge, the mating surfaces 14 and 15 of the runner plate 1 and the fixed mold plate 2 are closed, so that the air is discharged from the air release groove 35. Guide pin 20
Has penetrated deeply into the sliding hole at the end of its forward movement, and as shown in FIGS. 1 and 2, the fixed mold plate 2 and the movable mold plate 3 are in the mold closed position.

At the start of mold opening after resin molding, a mold opening force is applied to each mating surface of the runner plate 1, the fixed mold plate 2, and the movable mold plate 3. An attempt is made to open between the fixed mold plate 2 and the movable mold plate 3,
Along with this, the guide pin 20 tries to retreat from the sliding hole 21. Since the sliding hole 21 sealed by the O-ring 36 of the guide pin 20 is in a negative pressure state in response to the retreat, the air lock is activated by the wedge engagement of the lock surface 29 with the lock receiving surface 27. Will work. Therefore,
As shown in FIG. 3, the mating surfaces 14, 15 of the runner plate 1 and the fixed mold plate 2 having a mere adhesion force are first opened, and the runner R is projected.

In the mold opening limit, since the support pin 9 prevents further mold opening, a full mold opening force is applied to the air lock portion 23. As a result, the fixed mold plate 2 and the movable mold plate 3 are opened while resisting the air lock force of the air lock portion 23. In this case, since the sliding gap between the guide pin 20 and the sliding hole 21 is about 20 to 30 microns, the air lock is naturally released by sucking air from the sliding gap. Although not shown, a molded product is projected from the cavity 13 in the above-described mold open state.

According to the above-described embodiment, since the sealing portion can be formed by fitting the lid 22 to the guide bush 24, by directly adding to the conventional guide pin structure,
There is an advantage that it can be easily put into practical use.

As shown in FIG. 5, if the guide bush 24 is provided with a valve 40 as an air lock portion, the valve is in close contact with the hole side when locked, and the valve 40 opens in the imaginary line direction when the lock is released and air is discharged. Becomes A check valve that swings in the opening direction can be used as the valve 40, and can be provided in a storage groove 41 formed in the guide bush 24 with a check valve storage structure. Reference numeral 42 denotes a caulking or screwing portion for mounting the valve 40.

Also, as shown in FIG.
And the guide bush 51 is arranged corresponding to the movable mold plate 3. Guide bush 51 above
Is formed with an integral sealing portion 52, and the sealing portion 52 may be provided with an air lock portion 23. In this case,
It is desirable that the air escape groove 53 be formed large along the spacer block 5, and can be implemented only by mounting the guide bush 37 having the above structure. In addition, although the stopper plate for the spring 32 of the air lock unit 23 is illustrated, the movable plate 3 and the spacer block 5 are not separated because they are not separated.

The embodiments described above do not prevent implementation in combination with each other. Although the sliding pins 20 and 50 have been illustrated, the present invention is not limited to this, and other sliding pins that slide on the fixed plate 2 and the movable plate 3 can be used. For example, in a mold having a receiving plate that is separable from the movable mold plate 3, it is possible to design the movable mold plate 3 and the receiving plate to be first separable by providing an air lock portion using the above-mentioned sliding pin. is there.

[Effects of the Invention] As described above, the present invention has the following effects.

A sealing part is provided at the tip of the sliding hole of the sliding pin provided between the fixed mold plate and the movable mold plate, and the sliding pin advances and exhausts when the mold is closed, and slides at the start of the mold opening. By providing an air lock that locks the fixed mold plate and the movable mold plate with the inside of the hole under negative pressure, one of the mold plates and the other plate are opened first, and the parting line is later opened. I was able to.

A simple mold opening sequence structure using a sliding pin can be put to practical use, and can be provided as an existing assembly structure or a single structure.

[Brief description of the drawings]

FIGS. 1 to 4 show an embodiment of a resin molding die according to the present invention. FIG. 1 is an overall view of a closed state of a mold from a support pin, a cavity and a guide pin portion, and FIG. FIG. 3 is an enlarged sectional view of a main part of an air lock portion, FIG. 3 is a sectional view of the same in a mold opening order state, FIG. 4 is an enlarged sectional view of a main part in an air discharge state, and FIGS. It is a principal part expanded sectional view shown. 1 ... plate, 2 ... fixed mold plate, 3 ... movable mold plate, 5
... spacer block, 9 ... support pin, 11 ... runner part, 12 ... pinpoint gate, 13 ... cavity, 20, 50 ... sliding pin, 21 ... sliding hole, 22, 52 ... Sealing part, 23, 40 ... air lock part, 24, 51 ... guide bush, 28 ... lock piece, 35 ... air escape groove.

Claims (2)

(57) [Claims] 1. A movable mold plate, a fixed mold plate, and a plate separated from these mold plates, and a cavity line is opened after any one of the mold plates and the plate is first opened when the mold is opened. In the resin molding die, a sealing portion is provided at the tip of the sliding hole of the sliding pin between the solid mold plate and the movable mold plate, and the sliding pin moves forward and is exhausted when the mold is closed. A resin molding die, further comprising an air lock portion for locking the fixed mold plate and the movable mold plate by setting the inside of the sliding hole to a negative pressure state at the start of mold opening. 2. The resin molding die according to claim 1, wherein the sliding pins are guide pins.