JPS6227376Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a mold for insert molding.

Conventionally, in insert molding, an insert metal fitting to be inserted into a resin body is formed by punching a sheet metal into a predetermined shape and subjecting it to a predetermined bending process, even if the bent shape is somewhat complicated.

By the way, in insert molding, a part of the insert fitting is generally formed so as to protrude from the resin main body at one or more places. For this reason, a hole into which the protrusion of the metal insert fits tightly is formed in the surface forming the cavity of the fixed insert piece of the fixed mold and the movable insert piece of the movable mold.

However, according to the above-mentioned conventional insert molding, even when the insert metal fitting has a complicated bent shape, it is manufactured by integrally processing sheet metal, so it is difficult to increase the processing accuracy and the yield rate is low. In addition, even if insert metal fittings with such complicated bending shapes have good dimensional accuracy, if they are thin, they are likely to bend and deform during handling. If there are many protruding parts from the resin body,
There is a disadvantage that it takes time and effort to insert each protrusion into the hole of the movable insert piece, and furthermore, when the mold is clamped, the protrusion of the insert fitting against the hole of the fixed insert piece does not fit into the hole and becomes bent. There is a problem.

The above-mentioned drawbacks and inconveniences are less likely to occur when the bent shape of the insert is simple.

Therefore, in the present invention, when the insert fitting to be inserted into the resin body has a complicated bent shape, the divided parts are An object of the present invention is to provide a mold for insert molding with a novel structure in which the connection of the two parts can be performed within the mold when the mold is clamped.

The present invention will be specifically described below with reference to the illustrated embodiments.

In this embodiment, a mold having a fixed insert piece 2 and a movable insert piece 10 configured to insert and mold an insert fitting 4 having the overall shape as shown in FIG. 2 into a resin body (see FIG. 1) is used. ) is exemplified.

The insert fitting 4 has three divided parts 4a,
4b and 4c are connected to form the entire structure. The divided portion 4a includes protruding portions 4a-1 and 4a-2 that should protrude from the resin body, a bent connecting portion 4a-4, and a connecting portion 4a that connects the connecting portion 4a-4 to the protruding portions 4a-1 and 4a-2. -3, the dividing part 4b is approximately linear, and there are two pairs of notches 4b-3 on both sides in the middle.
1, 4b-2, and the dividing portion 4c is approximately L.
It is shaped like a letter and consists of a connecting portion 4c-1 and a protruding portion 4c-2 that protrudes from the resin body.

FIG. 1 shows a cross section of the mold. Fixed input piece 2
A plurality of thin shaft-shaped fixing inserts 3, two in this embodiment, are fitted into predetermined positions of , and the tip of each fixing insert 3 protrudes into the cavity 7, and each of the insert fittings 4 It is formed into a convex shape for connecting the divided parts. An insertion hole 31 for tightly inserting the protrusion 4a-2 of the divided portion 4a of the insert fitting 4 is bored in a part of the inner surface forming the cavity 7 of the fixed insert 2.

The movable insert piece 10 has a plurality of thin shaft-shaped movable inserts 11 corresponding to each of the above-mentioned fixed inserts, two in this embodiment.
The book is inserted. The center of the movable insert 11 is hollow, and a knockout pin 12 is inserted into the hollow part.
is urged in the knockout direction, that is, in the direction of the cavity 7, by a spring 13, and the spring 13 is housed in the movable mold 9 by a set screw 17. The inner diameter of the movable insert 11 corresponds to the outer diameter of the convex tip of the fixed insert 3 with some clearance. 10 movable pieces
Insertion holes 32 and 33 for tightly inserting the divided parts 4a and 4c of the insert fitting are bored in the inner surface forming the cavity 7. A thin shaft-shaped support member that supports the divided portion 4b is inserted and attached to the movable inserting piece 10. This support member 1
The tips of 5 and 25 protrude into the cavity 7 and have a forked shape, and as shown in FIG.
It is designed to fit.

The fixed insert piece 2 is attached to the fixed mold 1 with a plurality of bolts 16a, and the fixed mold 1 is further attached to a fixed mold mounting plate 23 with a plurality of bolts 26. Bolts 35 are attached to the fixed mounting plate 23.
The locate ring 34 is fixed by
A nozzle of an injection molding machine (not shown) comes into contact with the recess 36 of the locate ring 34.
A sprue 37 is bored through the locate ring 34, the fixed mold mounting plate 23, and the fixed mold 1, and the sprue 37 communicates with a runner 38 and a gate 39 and is guided into the cavity 7.

The movable insert piece 10 is attached to the movable die 9 by a plurality of bolts 16b, and the movable die 9 is further attached to the movable die mounting plate 24 via the plate 8 by a plurality of bolts 27. . An extruded lower plate 19 is fixed to the movable mounting plate 24 with a plurality of bolts 28, and an extruded upper plate 18 is fixed to the extruded lower plate 19 with a plurality of bolts 29. A plurality of push-out pins 14 and a plurality of return pins 20 are each fitted into the push-out plate 18 . Each push-out pin 14 penetrates the movable mold 9,
The tip thereof is exposed on the inner surface of the movable insert piece 10. Although the return pin 20 passes through the movable mold 9, care is taken so that the tip does not hit the fixed mold 1 when the mold is clamped. The guide pin 22 is fitted into the movable mold 9 and is adapted to slide within a guide bush 21 fixed to the fixed mold 1.

The structure of the mold according to this example is as described above, and the operation procedure thereof will be explained below.

When a mold attached to a molding machine (not shown) is opened, the protruding part 4a-1 of the divided part 4a of the insert fitting 4 is inserted into the insertion hole 32, and the connecting part 4a-4 is inserted into the movable insert. 11, and the protruding portion 4c- of the divided portion 4c.
2 into the insertion hole 33 and the connecting portion 4c-
1 on the tip of the movable insert 11, further place the divided portion 4b on the support members 15, 25, fit the bifurcated tips of the support members into the notches 4b-1, 4b-2, and position. , the connecting portions 4b-4 and 4b-5 at both ends thereof are connected to the connecting portion 4 of the divided portion 4a, respectively.
a-1 or the connecting portion 4c-1 of the divided portion 4c. After that, when the mold is clamped, the divided part 4
The other protrusion 4a-2 of a is inserted into the insertion hole 31, and at the same time as the mold is clamped, the ends of the fixed insert 3 and the movable insert 11 are pushed out as shown in FIG. Processing is performed. That is,
When the mold is clamped, the tip protrusion 3a of the fixed insert 3
is from the state immediately before mold clamping completion shown in Fig. 4 to the fourth stage.
As shown in FIG.
Each connecting portion c is relatively pushed into the recessed portion of the movable insert 11, that is, the hollow portion 11a. FIG. 4 shows the mold clamping completed state. Injection molding is performed in the state shown in FIG. 4, and the cavity 7 is filled with molten resin through the sprue 37, runner 38, and gate 39, and molding is performed. Once molding is complete, the mold is opened. Then, as shown in FIG. 4, the insert fitting 4 together with the resin body R,
After being knocked out by the knockout pin 12, the extrusion plates 18 and 19 move forward, and the molded product is ejected from the mold by the extrusion action of the extrusion pin 14.

When the extrusion plate is clamped after the insert fittings are set again, the return pin 2
The tip of 0 hits the fixed mold 1 and is pushed back to return to its original position.

When the mold is opened as described above, as shown in FIG. It is possible to achieve the same condition as if the insert fittings were manufactured by integrally molding sheet metal from the beginning and were embedded in the resin body.

As is clear from the specific description of the above embodiments,
According to the insert molding die of the present invention, by providing the fixed insert and the movable insert that face each other, it is possible to connect the divided parts of the insert fitting to each other during mold clamping.

As described above, according to the present invention, the metal insert can be divided into a plurality of divided parts each having a simple bent shape. Therefore, each divided part has a simple bent shape, which improves the production yield, and since the dimensions are small and there are few protrusions, there is less deformation during handling or due to mold heat.
The protrusion that protrudes outward from the resin body can be easily inserted into the insertion hole of the insert piece. Therefore, each divided part does not require extremely high dimensional accuracy, and the clearance between the insertion hole of the inserting piece and the protruding part of each divided part can be minimized, which prevents the occurrence of burrs and improves the accuracy of each divided part. It is possible to prevent the inclination of the

As a result of the above, both the productivity of insert metal fittings and the productivity of insert molding are improved.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a sectional view of an insert molding die, Fig. 2 is a perspective view of the insert fitting, and Fig. 3 shows the state in which the support member supports the divided portion of the insert fitting. Perspective view of main parts shown, No. 4
The figures are explanatory cross-sectional views sequentially illustrating the state in which the fixed insert and the movable insert approach each other during mold clamping and connect the respective divided portions of the insert fitting to each other. 1...Fixed type, 2...Fixed insert piece, 3...Fixed insert, 4...Insert metal fitting, 4a, 4b, 4c...
...Divide part of insert metal fitting, 7...Cavity,
9...Movable type, 10...Movable insert piece, 11...Movable insert, 12...Knockout pin, 13...Spring.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A fixed insert piece of a fixed mold and a movable insert piece of a movable mold are each provided with a predetermined pair of thin shaft-shaped inserts that protrude into the cavity, and The tip of each pair of inserts is formed such that one has a concave shape and the other has a convex shape that can be fitted into the concave shape, and when the mold is clamped, the two or more divided parts are connected to form the whole. The divided portions of the metal inserts constructed in this manner are overlapped at their connecting portions, and each overlapped portion is sandwiched between the above-mentioned pairs of inserts, and the convex tip of one insert is connected to the other insert. 1. A mold for insert molding, characterized in that the respective divided parts are fitted and connected to each other by being pushed into a recessed part at the tip. (2) In the insert molding mold described in claim 1 of the utility model registration claim, the insert having a concave tip is hollow, and the hollow portion is always provided with a spring on the cavity side. A pressed knock-out pin is inserted, and when the mold is opened, the connecting portion of the split portion of the insert fitting pushed into the recess at the tip of one of the inserts is pushed out by the knock-out pin 21. Something that is characterized by being done. (3) In the insert molding mold set forth in either claim 1 or 2 of the utility model registration claim,
The insertion piece having a recessed insert having a concave tip is characterized in that it is equipped with a thin shaft-shaped support member that supports the divided portion of the insert metal fitting.