JPH06106580A - Driving structure of movable member in mold - Google Patents

Abstract

PURPOSE:To prohibit parts from early wear in long time use and thereby enhance the reliability thereof by driving the movable member such as a runner stripper plate without causing any metal fatigue. CONSTITUTION:A repulsive member 28 for driving a runner stripper plate 6 is provided between a stationary side attaching plate 4 in a three plate type mold 2 and the runner stripper plate 6. The repulsive member 28 is composed of a pillar magnetic member 30 fixed on the recession 6a of the runner stripper plate 6 and a pillar magnetic member 32 fixed on the recession 4a in the opposite position of the stationary side attaching plate 4, wherein the magnetic member 30 and magnetic member 32 are positioned facing each other with the same S poles and N poles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold used for injection molding, press molding, and the like, and more specifically, a drive for automatically moving a moving member such as a runner stripper plate according to a mold opening operation. It is about structure.

[0002]

2. Description of the Related Art For example, in a sleep rate type of an injection molding die, in order to avoid that the sprue runner cannot be taken out if the parting surface is opened first when the die is opened, the parting is performed along with the die opening operation. The runner stripper plate is biased to open before the surface. The urging force is obtained by providing a coil spring as a repulsion member between a moving member such as a runner stripper plate and the counter plate.

[0003]

By the way, in the drive structure of the moving member such as the runner stripper plate by the spring elasticity, the structure can be simplified, but the breaking force due to metal fatigue and the restoring force due to the early attenuation of elastic energy during long-term use. Inevitable problems such as decrease in

Therefore, it is an object of the present invention to provide a driving structure for a moving member in a mold, which simplifies the structure and can maintain a stable driving force for long-term use.

[0005]

The present invention was devised to achieve the above object, and is characterized in that a repulsive member having a restoring force is brought into contact with a moving member such as a runner stripper plate to repel it. In the mold for driving the moving member by the restoring force of the member, the repulsion member is formed of a plurality of magnetic members facing each other with the same pole.

Further, according to the present invention, the repulsive member is laminated in the moving direction of the moving member, and a plurality of magnetic members adjacent to each other face each other with the same pole, and the repulsive member are not loosely inserted into these magnetic members. It may be configured by a magnetic guide shaft.

[0007]

According to the present invention, for example, a pair of magnetic members are made to face each other with the same pole on a fixed side mounting plate and a runner stripper plate as a moving member, and are fixed to each. When the mold is opened, the runner stripper plate repels the magnetic force between the magnetic members (restoring force) prior to the parting surface.
Then, the sprue runner is pulled out from the sprue bush. After that, the runner stripper plate stops at the proper position, the parting surface opens, and the product is ejected and the sprue runner is taken out.

Further, according to the present invention, the plurality of laminated magnetic members are separated by the repulsive force, whereby the stroke of the moving member is obtained, and the stroke is arbitrarily set depending on the number of magnetic members.

[0009]

1 and 2 show an embodiment of the present invention.
The figure shows a sleep rate type of injection molding die. The die 2 is provided with a fixed side mounting plate 4 and a runner stripper plate 6 on the fixed side, and a movable die plate 12, a receiving plate 14 on the movable side. The spacer block 16, the movable side mounting plate 18, the ejector plates 20 and 22, and the ejector pins 24 are provided. Reference numerals 8, 10, and 15 respectively indicate a sprue bush, a guide pin, and a guide pin bush, and reference numerals 25, 26, and 27 respectively indicate a core, a fixing bolt, and an ejector plate set screw.

A repulsion member 28 for driving the runner stripper plate 6 is provided between the fixed side mounting plate 4 and the runner stripper plate 6. The repulsion member 28 is composed of a cylindrical magnetic member 30 fixed to the concave portion 6a of the runner stripper plate 6, and a cylindrical magnetic member 32 fixed to the concave portion 4a of the fixed side mounting plate 4 at an opposing position. And the magnetic members 30 and 32 are S
They are facing each other with the same poles of N poles or N poles.

When the mold is opened after the resin is filled, as shown in FIG. 2, the runner stripper plate 6 is separated before the parting surface 33 by the repulsive force due to the magnetic force of the repulsive member 28, whereby the parting surface 33 is released. In the closed state, the mold opening operation proceeds while the sprue runner 34 is pulled out. Although not shown, when the proper position is reached thereafter, accompanying movement of the runner stripper plate 6 to the movable side is restricted, the parting surface 33 is opened, and the molded product 35 is ejected and the sprue runner 34 is taken out.

Since the runner stripper plate 6 is driven by the repulsive force due to the magnetic force, there is no concern about breakage due to metal fatigue observed in the spring member and early reduction of the repulsive force, and stable driving force is maintained for a long period of time. be able to. Although the repulsion member 28 is provided at one place in this example, a plurality of repulsion members 28 may be appropriately provided between the runner stripper plate 6 and the fixed-side mounting plate 4 within a range in which an appropriate repulsion force is obtained.

Next, FIGS. 3 and 4 show another embodiment. A repulsion member 36 is provided between the fixed side mounting plate 4 and the runner stripper plate 6. The repulsion member 36 includes a non-magnetic guide shaft 38 screwed and fixed in the recess 4b of the fixed-side mounting plate 4, and three ring-shaped magnetic members 40 loosely fitted in the guide shaft 38.
The magnetic members 40 face each other with the same pole. Further, the runner stripper plate 6 is formed with a recess 6b capable of accommodating the two magnetic members 40 in the mold closed state.
The moving hole 6c of the guide shaft 38 is continuously provided.

When the mold is opened, as shown in FIG.
The magnetic members 40 are separated by a repulsive force at equal intervals with a dimension d, whereby the movement stroke D of the runner stripper plate 6 is obtained. The stroke D can be arbitrarily set by changing the number of the magnetic members 40. When the stroke D is increased, the length of the spring member is increased, but since the magnetic member 40 can be dealt with only by the condition of the diameter, it is structurally advantageous as compared with the spring member.

Although each of the above-mentioned examples shows a specific shape, the present invention is not limited to this. For example, by fixing the guide shaft 38 to the runner stripper plate 6 side, an appropriate driving force by magnetic force can be obtained. The design can be changed appropriately within the range.

[0016]

According to the present invention, since the repulsive force (restoring force) due to the magnetic force can be obtained, problems such as early reduction of the restoring force due to repeated use and breakage due to metal fatigue are not caused, and long-term use is possible. A stable driving force can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an embodiment of a drive structure for a moving member in a mold according to the present invention.

FIG. 2 is a sectional view of an essential part showing the operation of a moving member associated with mold opening.

FIG. 3 is a sectional view of an essential part showing another embodiment.

FIG. 4 is a sectional view of an essential part showing the operation of the moving member associated with the mold opening of the example shown in FIG.

[Explanation of symbols]

 2 mold 6 runner stripper plate (moving member) 28, 36 repulsive member 30, 32, 40 magnetic member 38 guide shaft

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B29C 45/64 7365-4F

Claims (2)

[Claims] 1. A mold in which a repulsive member having a restoring force is brought into contact with a moving member such as a runner stripper plate, and the moving member is driven by the restoring force of the repelling member. A drive structure for a moving member in a mold, which is formed of a magnetic member. 2. A mold in which a repulsive member having a restoring force is brought into contact with a moving member such as a runner stripper plate, and the moving member is driven by the restoring force of the repulsive member, wherein the repulsive member has a moving direction of the moving member. A drive structure for a moving member in a mold, which is composed of a plurality of magnetic members that are stacked and arranged adjacent to each other with the same pole facing each other, and a non-magnetic guide shaft that is loosely inserted in these magnetic members.