JPH0213617B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a thermoplastic resin molded article with fittings suitable for use in manufacturing automobile scuff plates and the like.

Conventionally, as a thermoplastic resin scuff plate with metal fittings used at the lower edge of the entrance and exit of automobiles, the fourth
As shown in the figure, a projecting portion is provided so as to face the lower ends of one side wall 111 of the scuff plate 101 having a substantially U-shaped cross section and the leg portions 112 provided closer to the side wall than the center of both side walls. 113 and 114 are provided, and the legs of the clip fitting 102 are supported by the projecting portions 113 and 114. However, in the conventional product, the projecting portion 11
Since the parts 3 and 114 form so-called undercuts, the molding die has a complicated structure and is therefore expensive, and the positions of the projecting parts 113 and 114 are limited.

An object of the present invention is to provide a method for manufacturing a thermoplastic resin molded article with metal fittings that eliminates the above-mentioned conventional drawbacks.

Next, one embodiment of the present invention will be described based on the drawings. 1 is a polyethylene, polypropylene, or U-shaped cross section attached to the lower frame of the front door of a car.
The front scuff plate 1' is made of thermoplastic resin such as ABS resin, and the rear scuff plate 1' is also made of the same material and is attached to the lower frame of the rear door.

The clip fitting 2 is made of steel and has a substantially U-shaped cross section.
One side wall 21 is provided with a substantially rectangular through hole 211 having semicircular protrusions at both corners of the upper end, and a M for locking with other parts is formed diagonally inwardly upward from the lower end of the through hole. Letter-shaped clamping claws 212 are protruded, and both side walls 21,
Biting claws 23 are provided on both sides of the lower end of 22 to protrude obliquely outward. During manufacturing, first, the legs 12 that are intermittently protruded in the internal space of the front scuff plate 1 along the longitudinal direction and the outer wall 1 that is close to the legs are assembled.
The clip fitting 2 is inserted deeply into the recess formed by the clips 1 and 1 with the side wall 21 facing the outer wall 11 side. The biting claws 23 of the clip 2 press against the inner wall surface of the recess due to their elasticity, and the clip 2 is temporarily attached within the recess. In this state, the fifth
As shown in the figure, a high frequency oscillator 3 and coils 31 and 32 that form a magnetic field by the output of the high frequency oscillator 3
The coils 31, 3 of the high frequency induction heating device consisting of
2 are disposed on both sides of the clip fittings 2 on the outside of the scuff plate, and when the clip fittings 2 are heated by the high-frequency induction heating device to a temperature above the softening point and below the melting point of the thermoplastic resin constituting the scuff plate, the scuff plate is heated. The clip plate is not heated and the clip metal fittings 2
The heat of the biting claws 23 softens or melts the inner wall surface that the biting claws are in contact with, and the biting claws 23 bite into the inner wall surface, causing the clip fitting 2 to move into the recessed part. mounted on.

In the method of the present invention, the thermoplastic resin molded product is heated using a high-frequency induction heating device, so only the part that contacts the metal fittings is heated locally, and the entire part is not heated, so there is no risk of deformation as a whole. A molded product with a desired shape can be obtained without any problems.

According to the method of the present invention, the biting claws of the metal fittings bite into the wall surface of the thermoplastic resin molded product, so any number of metal fittings can be attached to any position in the recessed part of the molded product. It has the advantage of not requiring the use of complex and expensive molds.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an example of a molded product made by the method of the present invention, Fig. 2 is a sectional view taken along the line - Fig. 1, Fig. 3 is a perspective view of a clip fitting, and Fig. 4 is a perspective view of a molded product made by the conventional method. The cross-sectional view and FIG. 5 are explanatory diagrams showing a heating state using a high-frequency induction heating device. 1: Scuff plate, 2: Clip metal fittings, 2
3: Biting nail.

Claims (1)

[Claims] 1. A metal fitting with a biting claw is inserted into a concave part of a thermoplastic resin molded product, and in a state where the biting claw is pressing against the inner wall surface of the concave part of the molded product by its elasticity,
Heat with metal fittings characterized by heating the metal fittings with a high-frequency induction heating device, softening or melting the inner wall surface that comes into contact with the biting claws by the heat of the biting claws, and causing the biting claws to bite into the inner wall surface. Method for manufacturing plastic resin molded products.