JPS6141737B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for molding a dichroic lens used in a lamp for the rear of an automobile body, particularly a combination lamp.

Conventionally, the general method for molding this type of lens was to insert a previously molded lens body into a mold and mold it integrally. , the rotating core a
Using a multi-color molding machine having a mold consisting of a primary cavity B and a secondary cavity C provided on the left and right sides of the core A, first injection mold the lens body d in the primary cavity B, then mold the core A. There was also a method of injection molding the lens body e by rotating the lens body and connecting it to the lens body d through a secondary cavity c.

However, in the case where the previously molded lens bodies are inserted and integrally molded, a mold is required for each of the plurality of lens bodies, and the process of pre-molding and insert molding are separated, which reduces the number of steps. There were many drawbacks. Furthermore, those using a multi-color molding machine have the disadvantage that the multi-color molding machine is expensive and the investment amount increases.

The purpose of the present invention is to provide a molding method that eliminates the above-mentioned conventional drawbacks by molding a dichroic lens from a set of molds consisting of a male mold and a female mold. When molding a lens consisting of an upper lens body and a lower lens body of different colors, a thick part molded part and a thick part are placed between the upper lens molding part and the lower lens molding part which communicate with each other in the cavity of the mold. Range molding parts above and below the flesh part molding part are provided, synthetic resins of different colors are injected into the upper lens molding part and the lower lens molding part, respectively, and the synthetic resins of different colors are joined at the thick part molding part. In this method, a lens consisting of an upper lens body, a lower lens body, a thick part, and a thin part is molded, and after the lens is molded, the outer surfaces of the thick part and the thin part are coated with an opaque material.

Next, the present invention will be explained in detail based on an embodiment shown in FIGS. 2 to 4.

In the figure, 1 is a mold consisting of a male die 10 and a female die 11, and the cavity 2 of the die 1 consists of an upper lens body molding part 20 and a lower lens body molding part 21. It is provided in communication with the lower lens body molding section 21. As shown in FIG. 2, between the upper lens body molding section 20 and the lower lens body molding section 21, a flat surface is provided on the female mold 11 side, as shown in FIG. A thick part molding part 22 and a thin part molding part 23 are provided,
Thin-walled portion molding portions 23 are provided above and below the thick-walled portion-molding portion 22 .

Synthetic resins of different colors are injected from the two nozzles 3 and 4 connected to the female mold 11, for example, synthetic resin colored blue from the nozzle 3 to the upper lens body molding section 20, and from the nozzle 4. A synthetic resin colored red is injected into the lower lens body molding part 21, and the injected synthetic resins fill the upper and lower lens body molding parts 20, 21 and are joined at the thick part molding part 22. The thin-walled part molding part 23 has a male die 10 and a female die 11 in order to regulate the flow of the synthetic resin.
The upper lens body molding part 2 is narrower than the upper and lower lens body molding parts 20 and 21.
This prevents the synthetic resin satisfying 0 from flowing into the lower lens body molding part 21, and
This prevents the synthetic resin satisfying the above conditions from flowing into the upper lens body molding section 20. And thick part molding part 2
In order to regulate the bonding position of the synthetic resin filling the upper and lower lens body molding parts 20 and 21, the gap between the male mold 10 and the female mold 11 is set wider than that of the thin-wall molding part 23, and the synthetic resin The synthetic resins filling the upper and lower lens body molding parts 20 and 21 are bonded together by reducing the pressure as a water reservoir.

FIG. 3 shows the upper lens body 5 and the lower lens body 6 molded by the mold 1 described above, and the sprues and runners between the upper end of the upper lens body 5 and the lower end of the lower lens body 6 are connected at the gate part. A band-shaped molding f is attached to the outer surface of the thin wall portion 7 and the thick wall portion 8 between the upper lens body 5 and the lower lens body 6, and a strip molding f is formed on the outer surface of the thin wall portion 7. A dichroic lens is formed by hiding the synthetic resin joining line g. Note that instead of the molding, the outer surface of the thin wall portion and the outer surface of the thick wall portion may be hot stamped or painted.

Therefore, according to the method of the present invention, an upper lens body and a lower lens body of different colors can be integrally molded using a set of male and female molds, and it is also possible to join synthetic resins of different colors. Since the outer surface of the thick part where the line is formed is covered with an opaque material, molding costs and mold costs can be significantly reduced, and the strength of the joint surface of the synthetic resin is also improved because the joint is made of molten synthetic resin.
Compared to conventional bonding of solidified synthetic resin and molten synthetic resin, this method has excellent practical effects, such as significantly improved bonding strength.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a multicolor molding machine used in conventional dichroic lens molding, FIG. 2 is an explanatory diagram of a mold used in the dichroic lens molding method according to the present invention, and FIG. An explanatory view showing one embodiment of a dichroic lens molded by the method of the invention, FIG. 4 is a sectional view taken along the line of FIG. 3. DESCRIPTION OF SYMBOLS 1...Mold, 2...Cavity, 20...Upper lens body molding part, 21...Lower lens body molding part, 22
...Thick wall part molding part, 23...Thin wall part molding part, 5...
...Upper lens body, 6...Lower lens body, 7...Thin wall portion, 8...Thick wall portion, g...Synthetic resin bonding line.

Claims (1)

[Claims] 1. When molding a lens consisting of an upper lens body and a lower lens body of different colors, a thick part molding part and a thick part molding part are placed between the upper lens body molding part and the lower lens body molding part which communicate with each other in the mold cavity. Thin wall molding sections are provided above and below the thick wall molding section, and synthetic resins of different colors are injected into the upper lens body molding section and the lower lens body molding section, respectively, and the synthetic resins having different colors are formed in the thick wall molding section. A lens consisting of an upper lens body, a lower lens body, a thick part, and a thin part is molded by bonding resin together, and after the lens is molded, the outer surfaces of the thick part and the thin part are covered with an opaque material. A method for forming dichroic lenses.