JP2005343015A - Injection mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection mold constituted so as to always keep assembling precision higher than predetermined precision. <P>SOLUTION: The injection mold is provided with a fixed plate 7, a cavity plate and the slide part 4 held between them and constituted so as to link slide part 4 attached to a core plate to the opening/closing operation of the mold. The slide part 4 permits the angular pin 1, which is protruded from the fixed plate 7, to fit even at any position from the advance end to the retreat end of the slide part 4. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an injection mold used for molding.

A technology that makes it possible to adjust the cut-off amount at the press-cut part as an injection mold that uses the slide plate attached to the core plate to perform the molding process of the undercut part of the molded product in conjunction with the opening and closing operation of the mold. It has been known.
Such an injection mold has a sliding mechanism using an angular pin on a slide portion (slide core).

  In addition, a coil spring or a ball plunger is used in order to maintain the backward limit of the slide portion.

  As a conventional technique related to an injection mold using an angular pin, there is an “injection mold” disclosed in Patent Document 1. The invention disclosed in Patent Document 1 includes a gentle slope that is substantially parallel to an angular pin and that faces each other when the mold is closed, in a cavity plate and a slide core, and a shape variable member is interposed between the gentle slopes. The shape-variable member is positioned in a state where the protrusion is in contact with the engaging surface.

According to the invention disclosed in Patent Document 1, the slide core can be reliably locked at a required position, and the slide core does not open due to the filling pressure of the resin. Furthermore, the configuration is simple, and the operation of adjusting the slide amount of the slide core is not necessary.
Japanese Patent Laid-Open No. 9-216251

  However, since the coil spring is a consumable part, if the coil spring deteriorates and the elastic force weakens, the holding position of the slide part cannot be maintained, and the angular pin and the angular pin hole part of the slide part are displaced when the mold is closed. As a result, the angular pin and the slide part may be damaged.

  In the invention disclosed in Patent Document 1, the slide core is elastically biased by the restoring force of the shape-variable member. However, if the restoring force of the shape-variable member becomes weak as described above, there is a possibility that accurate positioning cannot be performed.

  Thus, the conventional injection mold cannot always maintain the precision at the time of assembling the mold above a predetermined precision.

  The present invention has been made in view of such problems, and an object of the present invention is to provide an injection mold that always maintains an assembly accuracy of a predetermined accuracy or higher.

  In order to achieve the above object, the present invention has a core plate, a cavity plate, and a slide part sandwiched between them, and the slide part attached to the core plate is interlocked with the opening / closing operation of the mold. An injection mold, wherein the slide part is fitted with an angular pin protruding from the cavity plate at any position from the forward end to the backward end. Is to provide.

  In the present invention, the angular pin is preferably installed at an attachment angle of 20 ° or less with respect to the opening and closing direction of the mold.

  In the present invention, the tip of the angular pin is preferably a surface perpendicular to the opening and closing direction of the mold, and in addition to this, the peripheral edge of the tip of the angular pin is chamfered. It is preferable that it is given.

  In any of the above configurations of the present invention, a convex portion extending in the longitudinal direction is provided on the outer peripheral surface of the angular pin, and a concave portion having a shape corresponding to the convex portion is provided on the inner wall surface of the pin hole for the angular pin of the slide portion. It is preferable that Alternatively, it is preferable that a concave portion extending in the longitudinal direction is provided on the outer peripheral surface of the angular pin, and a convex portion having a shape corresponding to the concave portion is provided on the inner wall surface of the pin hole for the angular pin of the slide portion.

  ADVANTAGE OF THE INVENTION According to this invention, the injection mold which always maintains the assembly precision more than predetermined precision can be provided.

  An injection mold according to a preferred embodiment of the present invention will be described. FIG. 1 shows an injection mold according to this embodiment. This injection mold has a structure in which a slide portion is supported by an angular pin at both the forward end and the backward end.

  The mounting angle of the angular pin is preferably 20 ° or less with respect to the opening / closing direction of the mold. By setting the angular angle of the angular pin to an obtuse angle with respect to the surface of the fixed plate (cavity plate), a large mold opening can be secured without increasing the size of the mold.

  As shown in FIG. 5, it is preferable that the tip of the angular pin is cut perpendicular to the opening and closing direction of the mold. By doing in this way, the full length of an angular pin can be shortened. Note that it is preferable to perform C or R chamfering on the periphery of the tip.

Moreover, as shown in FIG. 6, it is preferable to provide the unevenness | corrugation corresponding to the outer peripheral part of an angular pin, and the angular pin hole of a slide part, and to make it fit. As shown in (a), a convex rib may be provided on the outer peripheral surface of the slide pin, a concave groove may be provided on the inner wall surface of the angular pin hole, or a concave groove may be provided on the outer peripheral surface of the slide pin, A convex rib may be provided on the inner wall surface of the angular pin hole.
By providing such unevenness, the slide portion can be slid without being inclined with respect to the opening and closing direction.

  Thus, in the injection mold according to this embodiment, the slide portion is always fitted with the angular pin regardless of the position between the forward end and the backward end. Accordingly, there is no positional deviation between the slide portion and the angular pin. Further, since a coil spring and a ball plunger for elastically urging the slide portion are unnecessary, the deterioration of the die does not cause damage to the mold. Furthermore, the number of mold parts can be reduced, and the manufacturing cost can be reduced.

In addition, the said embodiment is an example of suitable implementation of this invention, and this invention is not limited to this.
For example, in the above-described embodiment, the description has been given by taking an example in which the angular pin is one, but a plurality of angular pins may be provided.
As described above, the present invention can be variously modified.

It is a figure which shows the sliding structure of the slide part in the conventional injection molding die. It is a figure which shows the sliding structure of the slide part in the conventional injection molding die. It is a figure which shows the holding structure of the slide part in the injection mold concerning this invention. It is a figure which shows the holding structure of the slide part in the injection mold concerning this invention. It is a figure which shows an example of the shape of the front-end | tip part of an angular pin. It is a figure which shows the cross-sectional shape of an angular pin and an angular pin hole, (a) is a case where the angular pin side is convex, and the angular pin hole side is concave, and (b) is an angular pin hole where the angular pin side is concave. This is a case where the side is convex.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Angular pin 2 Coil spring 3 Slide part angular pin hole 4 Slide stopper 6 Slide part 7 Fixed side plate

Claims (6)

A core plate, a cavity plate, and a slide part sandwiched between them; and the slide part attached to the core plate is an injection mold for interlocking with the opening and closing operation of the mold,
An injection mold, wherein the slide portion is fitted with an angular pin protruding from the cavity plate at any position from the forward end to the backward end.   2. The injection mold according to claim 1, wherein the angular pin is installed at an attachment angle of 20 ° or less with respect to the opening and closing direction of the mold.   The injection mold according to claim 1 or 2, wherein a tip portion of the angular pin is a surface perpendicular to an opening and closing direction of the mold.   The injection mold according to claim 3, wherein chamfering is performed on a peripheral edge of a tip portion of the angular pin.   A convex portion extending in the longitudinal direction is provided on the outer peripheral surface of the angular pin, and a concave portion having a shape corresponding to the convex portion is provided on an inner wall surface of the pin hole for the angular pin of the slide portion. The injection mold according to any one of claims 1 to 4.   A concave portion extending in the longitudinal direction is provided on an outer peripheral surface of the angular pin, and a convex portion having a shape corresponding to the concave portion is provided on an inner wall surface of the pin hole for the angular pin of the slide portion. The injection mold according to any one of claims 1 to 4.

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