JPS61137709A - Holding method of core - Google Patents

Abstract

PURPOSE:To surely form a synthetic resin layer over the whole rear side surface of a core and at the same time prevent the resin from boxing in the threaded part of a mounting bolt by a method wherein the core is held by pressing the mounting bolt part consisting in installing a clip, on the outer peripheral part of which a flange is made, on the outer side faces of which engaging claws are provided and within the main body of which a threaded hole is formed, to the mounting bolt part by screwing in a bolt receiving hole, near the inlet of which a neck part is provided and which is made on a mold. CONSTITUTION:Mounting bolt parts 3 onto each of which a clip 11 is installed, are pressed in the bolt receiving holes 18 of a mold 16. As for the pressed-in clip 11, the flange 13 tightly contacts with the cavity wall 17 and at the same time holds the neck part 19 of the bolt receiving hole 18 by pressing from the outside in cooperation with engaging claws 14, which closely engage with the neck part 19, so as to fix a core 2 through clips 11 to the mold 16. At this time, the thin-walled outer edge part of the flange 13 of the clip 11 seals the bolt receiving hole and at the same time leaves a clearance (a) between the core 2 and the flange 13.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for holding a core material during molding of a synthetic resin molded product in which a core material is embedded.

[Conventional technology]

Conventionally, when molding a synthetic resin molded product, a method as shown in FIG. 4, for example, has been used when embedding a core material having a bolt for attachment to another member.

For example, in a synthetic resin molded product 1 such as an air spoiler for an automobile, a metal core material 2 as shown in FIG. 5 is buried in order to maintain the shape of the molded product 1. Mounting bolts 3 are installed.

During this molding, if the core material 2 is brought into close contact with the cavity surface 5 of the mold 4, the core material 2 will be exposed on the back side of the molded product 1, making it impossible to obtain cushioning properties during installation.
There is also the problem that rust occurs in the core material 2.

Therefore, in the past, a magnet block 6 was attached to the mold 4 (the magnetic block 6 was made to attract and hold the metal core material 2, and the core material 2
The core material 2 is molded so that a constant distance is maintained between the core material 2 and the cavity surface 5 of the mold 4, so that the synthetic resin also wraps around the back side of the core material 2.

[Problem that the invention seeks to solve]

However, when the core material 2 is held by the magnet block 6 as described above, the synthetic resin does not enter the portion of the core material 2 that is in contact with the magnet block 6, and the core material 2 is still exposed in that portion. , prevent the occurrence of rust. There is a problem in that only that part needs to be painted. In addition, since the resin will also wrap around the threaded part of the mounting bolt, apply a mold release agent to this part in advance, and then remove the cured resin on the threaded part during molding to expose the threaded part. There was also the issue of having to do it.

The present invention aims to solve the above-mentioned problems by ensuring that a synthetic resin layer is formed on the entire back side of the core material, and by preventing the resin from getting around the threaded part of the mounting bolt. The purpose is to

[Means for Solving the Problems] The present invention provides a method for holding a core material provided with bolts for attachment to other parts in a mold when molding a synthetic resin molded product. A clip having a flange on the flange and a locking claw on the outer surface and having a threaded hole corresponding to the mounting bolt formed in the center part of the seven flange and into the main body part, is screwed into the mounting bolt through the threaded hole,
Press-fit the mounting bolt with this clip attached into the bolt storage hole that has a neck near the entrance of the mold, bring the flange of the clip into close contact with the cavity surface of the mold, and store the locking claw of the clip into the bolt storage hole. The core material is held by being engaged with the neck portion of the hole and being pressed and clamped by the seven flange and the locking claw.

[Effect]

In the present invention, a clip is attached to a bolt for attaching to another member of the core material, and this clip is press-fitted into a bolt storage hole of a mold, and the neck of the bolt storage hole is The core material is held by pressing and holding the core material.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 3.

This embodiment shows the case of molding a synthetic resin molded product 1 such as an air spoiler for an automobile, similar to the conventional example, and a core material 2 is embedded inside, and a plurality of pieces are embedded in this core material 2. A bolt 3 for attaching to another member is fixed.

Reference numeral 11 denotes a clip integrally molded from polyamide resin or the like, and this clip 11 has a hexagonal prism-shaped main body 12 at its tip outer periphery that is slightly inclined toward the main body 12 and gradually becomes thinner toward the outside. A circular flange 13 is provided, and a plurality of locking claws 1 are provided on the outer surface of the main body 12.
4 is provided, and a screw hole 15 corresponding to the mounting bolt 3 is provided in the main body part 12 from the center of the flange 13.
is formed.

16 is a mold, and this mold 16 has a cavity surface 17.
Bolt storage holes 18 corresponding to the three mounting bolts mentioned above.
A narrow neck portion 19 is formed near the entrance of this bolt storage hole 18.

When molding the molded product 1, first, the core material 2
Screw the clip 11 onto each mounting bolt 3 through its screw hole 15 using a hexagon socket screwdriver, wrench, or the like.

Next, attach the mounting bolts 3 to which each clip 11 is attached.
press fit into the bolt housing hole 18 of the mold 16.

In this press-fitted clip 11, the 7 langes 13 are connected to the mold 1.
The locking claw 14 is in close contact with the cavity surface 17 of 6.
is closely engaged with the neck portion 19 of the bolt storage hole 18 and pressed from the inside, and the 7 langes 13 and the locking pawls 14 cooperate to press and hold the neck portion 19 from the inside and outside. is fixed to the mold 16 via the clip 11.

At this time, the outer edge portion of the flange 13 of the clip 11, which is gradually thinned toward the outside, is pressed against the cavity surface 17 of the mold 16 to seal the bolt housing hole 18.

This prevents the synthetic resin material from entering into the bolt storage hole 18, and also forms a clearance a between the 7 langes 13 and the core material 2, so that the synthetic resin material can reach the base of the mounting bolt 3. Entry is possible. In order to form this clearance a, attach the mounting bolt 3 to the clip 1.
The flange 13 may be set in advance so that when the flange 13 is screwed in until it contacts the bottom surface of the screw hole 15 of No. 1, the flange 13 is separated from the surface of the core material 2 even at its center.

In this way, a synthetic resin molded product is molded using urethane resin or the like using the mold 16 and other molds (not shown) corresponding thereto.

After molding, the clip 11 can be easily removed since the urethane resin has no adhesive effect on the polyamide.

〔Effect of the invention〕

According to the present invention, a clip is attached to the mounting bolt of the core material, the clip is press-fitted into the bolt storage hole of the mold, and the neck portion of the bolt storage hole is pressed by the seven lunges of the clip and the locking claw. Because it is held in place by pinching, the core material can be held away from the gear and tee surfaces of the mold, allowing molding without exposing the core material, eliminating concerns about rust, and saving the labor of painting. It is possible to prevent resin from adhering to the threaded portion of the bolt. Moreover, a lightweight and inexpensive core material such as FRP other than a metal core material can also be used.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing one embodiment of the method of the present invention, FIG. 2 is a perspective view of a part thereof, FIG. 3 is a cross-sectional view of a clip, and FIG.
The figure is a sectional view showing a conventional method, and FIG. 5 is a perspective view of the core material. 1. Synthetic resin molded product, 2. Core material, 3. Mounting bolt, 11. Clip, 12. Main body, 13. 7 langes, 14. Locking claw, 15. Screw hole. , 16... Mold, 17... Cavity surface, 18... Bolt storage hole, 19
...Nereku Club.

Claims (1)

[Claims] (1) In a method of holding a core material with bolts for attachment to other parts in a mold when molding a synthetic resin molded product, the main body has a flange on the outer periphery of the tip and a locking claw on the outer surface. A clip having a threaded hole formed in the center of the flange and corresponding to the mounting bolt in the main body is screwed onto the mounting bolt through the threaded hole, and the mounting bolt portion with the clip attached is inserted into the inlet of the mold. Press fit into the bolt storage hole that has a neck part nearby,
By bringing the flange of the clip into close contact with the cavity surface of the mold, and locking the locking claw of the clip to the neck of the bolt storage hole, the flange and locking claw press and hold the neck of the bolt storage hole. A core material holding method characterized by holding the above-mentioned core material.