JP2009190359A - Core material insert molding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a core material insert molding method with which, even when a metallic core material is supported to the prescribed position of a cavity and the raw material of a rubber-like elastic body is injected, it is not moved by pressing at the inside of the cavity, and further, a means of supporting the core material to the inside of the cavity is prevented from being exposed to the surface of a molding and thus appearance of the molding is not spoiled. <P>SOLUTION: The insertion part 25 of a projection 23 is forcedly pressed into the fitting hole 22 of a metallic core material 21, thus it is fitted and fixed to a neck part 24, and the projection 23 is brought into contact with a die 8 forming a cavity 11 to support the core material. By making the material of the projection 23 the same as that of a rubber-like elastic body of the molding, even when the tip of the projection is exposed to the surface of the molding, it is made inconspicuous. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an insert molding method for preventing a core material from being exposed on the surface of a molded product.

  A weather strip is one of molded articles made of rubber or resin into which a core material is inserted. FIG. 2 shows an extrusion-type weather strip (not shown) which is assembled to a molded part 1 of a weather strip to be assembled to part a of the convertible vehicle shown in FIG. 1, ie, a rear pillar 2 and seals between the side glass. FIG. 3 shows a molded part 1 that connects an extruded weatherstrip (not shown) that is orthogonal to the weatherstrip and seals between the rear glass, and FIG. 3 is taken along line AA in FIG. A cross-sectional shape is shown, and a bent core material 3 made of metal or hard resin is inserted.

  FIG. 4 shows a mold used to mold the mold molding part 1, which comprises a fixed lower mold 5, left and right slide molds 6, 7, 8, and an openable upper mold 9. A cavity 11 having the same cross section as that of the mold forming portion 1 shown in FIG. 3 is formed by the molds 5, 6, 7, 8, and 9. After molding, the core material 3 is set in the cavity and assembled to the mold. A raw material of rubber-like elastic body such as rubber or thermoplastic elastomer is injected into the cavity 11 through the sprue 12 and the gate 13 from a nozzle of a molding machine (not shown). At the time of injection, the core material 3 is pushed and moved by the pressure of the raw material and is pressed against the slide mold 8 shown in the figure, which tends to be exposed from the molded product and impair the appearance. In order to solve this problem, as shown in FIG. 5, a method of projecting presser pins 15 and 16 on the lower mold 5 and the slide mold 8 to support the core material 3 by sandwiching it from both sides and holding it in the cavity. As shown in FIG. 6, a method of holding the core material 3 in the cavity with the projecting portion 17 projecting from the holding pin 13 and the core material 3 protruding from the lower mold 5 and hitting the slide mold 8 has been conventionally performed. Has been.

  In the molding method in which the core material set in the cavity is held with a presser pin protruding from the mold, there is a problem that the mark of the presser pin remains in the molded product, and the core material is held by the protruding portion protruding from the core material. In the molding method, the tip of the protruding portion is exposed to the molded product, and the appearance tends to be impaired.

  An object of this invention is to provide the insert molding method of the core material which solved said problem.

The invention according to claim 1 is an insert method in which a metal or resin core material is set in a cavity of a mold, and then a rubber-like elastic material is injected into the cavity, and the cavity is formed in the core material. A hard rubber or hard resin that supports the core when hitting the mold, preferably a protrusion made of a rubber-like elastic body made of the same material as the raw material is fixed or fixed,
The invention according to claim 2 is the invention according to claim 1, wherein the core member is provided with attachment holes at one or a plurality of locations, and each attachment hole has a neck portion having a smaller diameter than the attachment hole, and is integrated with the neck portion. The protrusion having a larger diameter insertion portion than the attachment hole is attached by forcibly fitting the insertion portion into the attachment hole.

  According to the first aspect of the present invention, the core material is supported by the protrusion of the core material hitting the cavity mold and can be prevented from being pushed and moved in the cavity when the raw material is injected. Therefore, even if the tip is exposed on the surface of the molded product, there is an effect that it is difficult to stand out. If the projection is formed of the same material as the molded product, it becomes even less conspicuous.

  The protrusions can be fixed or fixed to the core material by bonding. However, if the core material is provided with an attachment hole and forcedly fitted into the attachment hole as in the invention according to claim 2. Fixing or fixing is performed reliably, and fixing can be easily performed because it is only necessary to push the insertion portion strongly into the mounting hole.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 7 shows a metal core member 21 inserted into the molding part 1 shown in FIG. 2, and a large number of mounting holes 22 are formed at regular intervals or at random. FIG. 8 shows a protrusion 23 made of a rubber-like elastic body that is harder than a rubber-like elastic body such as rubber or thermoplastic elastomer, which is a material of the molded product. The protrusion 23 is fixed to the core member 21 by being formed integrally with the object 23 in a symmetric form, and by pressing the insertion portion 25 into the mounting hole 22 and forcibly fitting it.

  FIG. 9 shows a state in which the core material 21 to which the protrusion 23 is fixed is set in the cavity 11. The protrusion 23 protruding from the core material 21 and the insertion portion 25 form the lower mold 5 and the slide. The protrusion 23 and / or the insertion portion 25 supported by being hit by the mold 8 and sandwiched between the lower mold 5 and the slide mold 8 are crushed by about 0.2 to 1.5 mm.

  The molding is performed by setting the core material 21 in the cavity as shown in FIG. 7 and then injecting the raw material of the rubber-like elastic body into the cavity 11 through the sprue 12 and the gate 13.

  According to the present embodiment, the protrusion 23 can be securely fixed by firmly pressing the insertion portion 25 into the attachment hole 22 of the core member 21 and fitting the neck portion 24 into the attachment hole 22. The protrusion 23 fixed to the contact with the lower mold 5 and the slide mold 8 forming the cavity 11 together with the insertion portion 25 protruding to the opposite side can support the core material 21 at a predetermined position in the cavity. Since the rubber-like elastic body is made of the same material as that described above, the tip exposed on the surface of the molded product is inconspicuous, and other parts are not damaged even if they come into contact with other parts.

  The protrusion 23 may or may not be bonded to the raw material. If they are bonded, the airtightness between the projection 23 and the molded product around the projection 23 is increased, and water can be prevented from entering the vehicle from outside the vehicle through the gap between the projection 23 and the molded product. preferable. In order to adhere, it is conceivable that the protrusion 23 is degreased or a primer or an adhesive is applied to the protrusion 23 to improve the adhesion with the raw material.

  FIG. 10 shows another example of the protrusion, which includes an insertion portion 28 with a neck portion 27 interposed therebetween, and a retaining portion 30 having a larger diameter than the insertion portion 28 and a pin 29 protruding therefrom.

  FIG. 11 shows still another example of the protrusion, in which the retaining portion 30 shown in FIG. 10 is a retaining portion 32 having a mountain-shaped cross section, and the rigidity of the retaining portion 32 is increased, and the slide molds 6, 7, When 8 is closed, it is difficult to deform by hitting the slide mold.

  Although the core material 21 of the said embodiment shows the example used for the shaping | molding part of the weather strip assembled | attached to the a part of the convertible vehicle shown by FIG. 1, other core materials of a weather strip, for example, U The same effect can be obtained by forming the core material inserted in the mounting base of the cross section in the same manner, and the core material inserted in the molded product other than the weather strip is configured in the same manner as described above. Similar effects can be produced.

1 is a schematic side view of a convertible vehicle. The perspective view of the shaping | molding part of the weather strip assembled | attached to the a part of FIG. The expanded sectional view in the AA line of FIG. Sectional drawing of the metal mold | die which shape | molds the shaping | molding part shown in FIG. Sectional drawing of the principal part of the conventional metal mold | die. Sectional drawing of the principal part of another example of the conventional metal mold | die. The perspective view of the core material which concerns on this invention. The front view of the protrusion attached to the attachment hole of the core material shown in FIG. Sectional drawing of the principal part of the metal mold | die which set the core material which concerns on this invention to the cavity. The front view of another example of a protrusion. The front view of the other example of a protrusion.

Explanation of symbols

5. Lower mold 6, 7, 8 .. Slide mold 9. Upper mold 11. Cavity 12. Sprue 13. Gate 21. Metal core member 22. Mounting hole 23. Projection 24. 27..Neck part 25, 28..Insertion part 29..Pins 30, 32..Retaining part

Claims (2)

  In an insert method in which a core material 21 made of metal or resin is set in the cavity 11 of the mold 5, 6, 7, 8, 9 and then a rubber-like elastic material is injected into the cavity, An insert molding method for a core material, characterized in that a protrusion 23 made of a rubber-like elastic body of hard rubber or hard resin that supports the core material 21 is fixed to or fixed to a mold that forms the cavity 11.   Mounting holes 22 are formed in one or a plurality of locations in the core material 21, and each mounting hole 22 is integrated with neck portions 24 and 27 having a smaller diameter than the mounting holes 22, and the neck portions 24 and 27. The insert molding of the core material according to claim 1, wherein the protrusions 23 having larger-diameter insertion portions 25, 28 are attached by forcibly fitting the insertion portions 25, 28 into the attachment holes 22. Method.

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