JPS6213767Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an injection molded product having a multi-component integrally molded structure.

For example, synthetic resin bumpers for automobiles have decorative parts (molding, ornaments, etc.) on the surface of the resin body.
These decorative parts are usually attached to the surface of the main body by fitting or gluing, or by mechanical means such as bolts, nuts, screws, rivets, etc. For example, see Japanese Utility Model Application No. 53-105247).

Alternatively, a method has been used in the past in which a decorative part is formed on the surface of the main body itself by hot-stamping the surface of the main body partially or by partially painting the entire surface of the main body without using decorative parts.

All of these conventional methods have the disadvantage of increasing man-hours and costs.

These disadvantages in terms of man-hours and costs could be overcome if the decorative parts were molded and joined together when the main body was injection molded, but if the decorative parts were molded separately and then placed inside the mold for the main body. When the raw material for the main body is injected with the setting set to I get used to it.

The object of the present invention is to provide a structure of a molded article that does not look unsightly when formed by integral injection molding as described above, and will be described below with reference to the accompanying drawings.

1 and 2 show an example in which the present invention is applied to an automobile bumper, in which 1 is a main body part, 2 is a decorative part, the decorative part 2 is separately molded in advance, and the main body part 1 During injection molding, the decorative part 2 is set in the mold and a part of the decorative part 2 is molded inside the main part 1, and the decorative part 2 is integrally molded.

The decorative component 2 is configured such that a portion 2b to be molded onto the main body component 1 is concave to a larger extent than the surface portion 2a, and a parting groove 3 is formed along the entire circumference of the parting part when it is molded onto the main body part 1. The parting portion is configured to be located at a position considerably deeper than the surface 1a of the main body part 1 and the surface 2a of the decorative part 2.

Furthermore, a decorative part 2 serving as the bottom of the parting groove 3 is provided.
A small groove forming a continuous parting line is formed in the part where the surface of the part 2b and the surface of the main body part 1 which becomes the outer wall of the parting groove 3 are in contact with each other.
Processed and configured.

A molding operation for a molded article having the above-mentioned structure will be explained with reference to FIG.

In FIG. 3, 4 is a lower mold, and 5 is an upper mold. The lower mold 4 includes a position regulating holding part 41 of the decorative part 2 and a blade-shaped part 42 protruding around the part corresponding to the parting part.
The upper mold 5 is provided with a large number of pressure holding parts 51 that protrude to face the blade part 42 at predetermined intervals.

The decorative part 2 is set in the above-mentioned mold while being positioned by the position regulating holding part 41, and the mold is clamped.

Then, the portion 2b of the decorative component 2 is pressed by the pressure holding portion 51, and the blade portion 42 is in a biting state.

Then, raw materials are poured into the mold, and the outer periphery of the part 2b of the decorative part 2 is molded on the surface of the main body part 1, thereby obtaining a molded product in which the two parts are integrally joined.

In the molded product constructed in this way, the parting line is located at the back of the parting groove 3 as described above, and the parting line is not noticeable in appearance, so even if there is some burr on the parting line. Even if this occurs, it will not cause any problem in terms of appearance, and on the contrary, the parting groove 3 will serve as an accent to the overall design, creating the effect of creating a fresh sense and sense of depth.

Furthermore, by providing the decorative member 2 with a large step as described above, when the decorative member 2 is set in a mold as shown in the third figure, the step has a function as a position regulating portion and the parting groove 3 is Since the inner part is almost invisible from the outside, it is not a problem even if some scratches are caused by biting the blade part as shown in Figure 3. This can have the effect of preventing raw materials from flowing out.

This idea is applicable not only to automobile bumpers as in the above example, but also to any molded product that is to be integrally injection molded (including reaction injection molding) with other molded parts partially molded. Needless to say.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an embodiment of the present invention applied to an automobile bumper, and Fig. 2 is an A-A in Fig. 1.
FIG. 3 is a cross-sectional view showing a molded form of the one shown in FIG. 1. 1... Main body parts, 2... Decorative parts, 1a, 2a
... surface part, 2b ... part to be molded,
3...Ditch.

Claims (1)

[Scope of utility model registration request] In an injection molded product that is integrally molded with a part of another molded part molded into the main part, a parting groove recessed from the surface part is continuously provided at the parting part between the main part and the other molded part, and the parting groove is An injection molded product having a multi-component integral molding structure, characterized in that a small groove forming a continuous parting line along the side wall of the parting groove is provided in the parting part at the bottom.