JPH0224649B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to an insert molding method and an insert member, and particularly to an insert molding method and an insert member suitable for use in multicolor molding and the like.

"Prior art" Generally, when performing multi-color molding, etc., the molded product is divided into multiple parts (for example, divided by color), a part of which is molded in advance, and the primary molded product is used as an insert member for secondary molding. A so-called insert molding technique is used.

By the way, in this type of insert molding, there is a need to give the finished product a good appearance, so there is a risk of galling between the mold and insert member during mold clamping, or that the molten resin filled during secondary molding is damaged by the insert. There is a strong demand for preventing the occurrence of so-called fogging, which occurs when the material wraps around the surface of the member.

Therefore, conventionally, as shown in FIG. 1, insert member 2 is attached to core plate 1 in a tight state, cavity plate 3 is butted against core plate 1, and then both molds 1 and 3 are clamped. In particular, as shown in FIG. 2, the insert member 2 is clamped and pressed between the two molds 1 and 3 in a state of surface contact.

However, in the conventional method mentioned above,
The following problems remain to be improved.

That is, since the size of the cavity formed by both the molds 1 and 3 is determined by the parting surfaces of the molds 1 and 3 being brought into contact with each other, the mold In order to keep the contact pressure between the insert member and the insert member within an allowable range, it is necessary to finish the shape and dimensions of the insert member with high precision, and the accuracy is, for example,
It is in the range of 0.03-0.05mm. If the dimensions of the insert member 2 exceed the above-mentioned range and are larger than the dimensions of the cavity, the insert member 2 may be deformed or cracked due to the pressure during mold clamping, and the cavity may exceed the above-mentioned range. If the size is smaller than , the above-mentioned fogging phenomenon will be induced. In particular, when the aforementioned insert member 2 is molded from synthetic resin, it is extremely difficult to maintain the dimensions of the aforementioned insert member 2 within an allowable range in terms of molding accuracy and variations thereof. It becomes work.

``Object of the Invention'' The present invention has been made in view of the conventional circumstances described above, and its purpose is to prevent damage to the insert member during mold clamping and to improve the dimensional accuracy of the insert member. The purpose is to provide an insert molding method that can absorb variations and prevent fogging of molten resin during subsequent molding.
Another object of the present invention is to provide an insert member for effectively carrying out the above-described insert molding method.

"Structure of the Invention" In order to achieve the above-mentioned object, the first aspect of the present invention is
The invention provides an insert member that is placed in one of a pair of molds comprising a core plate and a cavity plate that form a cavity for insert molding, with an insert member spaced apart from said one mold and elastically attached to said one mold. The molds are mounted so as to be relatively movable, and the one mold is butted against the other mold and the molds are clamped to form a cavity surrounding the insert member and press the insert member against the other mold, and then the mold is pressed against the other mold. The insert member of the second invention is characterized in that it is integrated with the insert member by filling a molten resin into the cavity and solidifying it, and the insert member of the second invention has an elastically deformable part that protrudes outward from the side edge of the insert main body. A supporting piece is integrally provided at the protruding end of the supporting piece, and engages with one of the molds to form a gap between the one mold, the insert body, and the supporting piece, and The insert body is characterized by being integrally provided with an elastically deformable engagement protrusion that presses the insert body into contact with the other mold.

"Example" The present invention will be described below based on an example shown in FIGS. 3 to 6. In the following explanation, the same reference numerals are used for the parts common to FIGS. 1 and 2 to simplify the explanation. Furthermore, in the following description, one mold will be described as a core plate, and the other mold will be described as a cavity plate.

In FIGS. 3 and 4, the reference numeral 4 indicates the first
The insert member used in the invention, that is, the second
This shows one embodiment of the invention, and the insert body 5
An elastically deformable support piece 6 that projects outward is integrally provided on the side edge of the support piece 6, and the protruding side end of the support piece 6 is engaged with the core plate (indicated by a chain line in FIG. 3) 1. A gap G is formed between the core plate 1, the insert body 5, and the support piece 6, and a cavity plate 3 (not shown in FIGS. 3 and 4) is clamped to the core plate 1. Occasionally,
The cavity plate 3 cooperates with the support piece 6.
It has a schematic structure in which an elastically deformable engagement protrusion 7 that presses the insert main body 5 is integrally provided.

The insert member 4 is formed by primary molding of synthetic resin, and during the primary molding, each component is molded simultaneously. The support piece 6 and the engagement protrusion 7 are made thinner or have a smaller diameter than the insert body 5, so that they can be elastically deformed.

Next, an embodiment of the insert molding method according to the first invention will be described using the insert member 4 according to the second invention described above with reference to FIGS. 5 and 6.

First, as shown in FIG. 5A, the core plate 1
By fitting the engaging protrusion 7 of the insert member 4 into the positioning hole 8 provided in the cavity forming surface 1a of the core plate 1, a gap G is created between the insert member 4 and the cavity forming surface 1a of the core plate 1. and attach it.

Next, by butting the cavity plate 3 against the core plate 1 and clamping both the molds 1 and 3, as shown in FIG. 5B,
A cavity 9 surrounds the insert member 4.
and the elastic force of the support piece 6 and the engagement protrusion 7 of the insert member 4 causes the insert body 5 to be attached to the cavity forming surface 3 of the cavity plate 3.
Press it against a.

As shown by the arrow in FIG. 5B, molten resin is introduced into the cavity 9 in which the insert member 4 is disposed through the gate 10 provided in the core plate 1 facing the insert member 4. By filling and solidifying, the filled resin P is integrated with the insert member 4 as shown in FIG. 5C.

The insert molding of this embodiment is then completed by opening the molds 1 and 3 and releasing the integrated insert member 4 and the filled resin P as described above.

When insert molding is performed by such a method, even if the insert member 4 attached to the core plate 1 and the cavity plate 3 come into contact when the two molds 1 and 3 are butted together, the insert member 4 Since the insert member 4 is elastically supported by the core plate 1, the insert member 4 moves relative to the core plate 1 and is prevented from galling with the cavity plate 3. Further, even if there is a dimensional variation in the insert member 4, it is absorbed by the relative movement between the insert member 4 and the core plate 1 as described above, and damage caused by overcompression of the insert member 4 is prevented. Ru. Furthermore, after the molds 1 and 3 are clamped, the insert member 4 is brought into pressure contact with the cavity forming surface 3a of the cavity plate 3, and there is a gap between the insert member 4 and the core plate 1. G is provided, and the molten resin to be filled flows into the gap G to further increase the pressure contact between the insert member 4 and the cavity plate 3, thereby preventing the insert member 4 from being covered. In particular, in this embodiment, the gate 10 is provided on the core plate 1 to face the insert member 4, and the molten resin is filled by directly injecting it perpendicularly to the insert member 4, so that the above-mentioned fog prevention effect is achieved. It becomes noticeable.

Therefore, as shown in FIG. 6, the insert molded product 11 has a clear boundary between the insert member 4 (insert main body 5) and the filled resin P, and has a uniform appearance.
is obtained.

On the other hand, when the insert member 4 of the second invention shown as an embodiment is used, the insert body 5 can be easily moved at a distance from the core plate 1 and elastically by the support pieces 6 and the engagement protrusions 7. The insert molded product 11 can be easily attached to the cavity plate 3, can be easily brought into pressure contact with the cavity plate 3, can effectively carry out the first invention, and can obtain an insert molded product 11 with a uniform appearance. In addition, the support piece 6
Since the engagement protrusion 7 and the insert body 5 can be molded at the same time, the insert molding work is simplified. Furthermore, in the insert member 4 of this embodiment, when the filling resin P solidifies, it solidifies surrounding the support piece 6 and the engagement protrusion 7, so that the insert member 4
The connection between the filling resin P and the filling resin P becomes strong.

Note that the shapes of the insert member 4 and the insert molded product 11, the shapes of the support piece 6 and the engaging protrusion 7, the installation locations, etc. shown in the above embodiments are merely examples, and can be changed in various ways based on design requirements. .

"Effects of the Invention" As explained above, the present invention provides the following excellent effects.

To prevent galling between a mold and an insert member when the mold is clamped, and also to prevent fogging on the insert member, thereby suppressing damage to the insert member and eventually the insert molded product, and obtaining an insert molded product with a uniform appearance. be able to.

Absorbs variations in the dimensional accuracy of insert members, suppresses damage to the insert members, improves product yield, and widens the tolerance range of mold machining accuracy, reducing mold manufacturing costs. In addition, production costs can be reduced.

[Brief explanation of drawings]

Figures 1 and 2 show an example of a conventional insert molding method, with Figure 1 being a vertical cross-sectional view showing the state in which the insert member is attached, and Figure 2 being a vertical cross-sectional view showing the state after mold clamping. , FIG. 3 to FIG. 6 show an embodiment of the present invention, FIG. 3 is a front view showing an embodiment of the second invention, and FIG.
FIG. 5 is a process diagram showing an embodiment of the first invention, and FIG. 6 is an external perspective view of an insert molded product molded according to the embodiment. 1...Core plate (one mold), 1a...
Cavity forming surface, 3... Cavity plate (the other mold), 3a... Cavity forming surface, 4...
...Insert member, 5...Insert body, 6...
...Support piece, 7...Engaging protrusion, 8...Positioning hole,
9... Cavity, 10... Gate, 11... Insert molded product, P... Filled resin, G... Spacing.

Claims (1)

[Scope of Claims] 1. An insert member is placed in one of a pair of molds comprising a core plate and a cavity plate forming a cavity for insert molding, with a space between the insert member and the mold. By elastically attaching the molds so that they can move relative to each other and clamping the molds by abutting the other mold, a cavity is formed surrounding the insert member, and the insert member is pressed into contact with the other mold. and then filling the cavity with molten resin and solidifying it to integrate it with the insert member. 2. The insert molding method according to claim 1, wherein the molten resin is filled from one mold to an insert member facing the one mold. 3. An insert member disposed in a cavity formed by a mold consisting of a pair of core plates and a cavity plate, which includes an elastically deformable support that protrudes outward from the side edges of the insert body. a piece is integrally provided, and the protruding end of the support piece engages with the one mold to form a gap between the one mold, the insert body and the support piece, and the insert body An insert member characterized in that it is integrally provided with an elastically deformable engagement protrusion that presses the insert member into contact with another mold.