JPS6345294B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a resin injection molding apparatus.

Configuration of Conventional Example and Its Problems As shown in a specific example in FIG. Rotate screw 1.

The raw material supplied into the cylinder 2 from the hopper 6 is heated by the shear heat generated by the rotation of the screw 1 and by the external heater 7.
It is plasticized by heating from and is accumulated in the front part of the cylinder 2. Next, by operating the injection cylinder 3, the screw 1 advances to inject the plasticized raw material.

The problems with the conventional example described above are that the screw 1 has a complicated structure because it performs rotational movement and back-and-forth movement in the axial direction, and it is necessary to have a separate drive source for both movements. .

In addition, since it takes a long time to raise the temperature of the heater 7, it is necessary to turn on the heater 7 20 to 30 minutes before the start of molding, which may cause a big problem when, for example, connecting the molding machine and the assembly line or synchronous operation. Ta.

Purpose of the Invention The present invention solves the above-mentioned disadvantages of the conventional technology, and since it sequentially melts linear or belt-shaped molding materials, it can be configured with a small-capacity heating source and enables efficient material melting. That is.

Composition of the Invention The present invention includes a material transfer section for transferring a linear or belt-shaped resin molding material in the axial direction, an injection plunger having a through hole having a cross-sectional shape substantially the same as the cross-sectional shape of the resin molding material, and the injection plunger. The gist is a resin molding apparatus consisting of a non-conductive melting cylinder having one end open facing the resin molding material, an injection nozzle at the other end, and high-frequency dielectric heating means for melting the resin molding material. Alternatively, the material can be melted efficiently in a short time by making it into a belt and feeding it into a melting cylinder one after another to melt the small amount required for one injection.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below based on FIG. 2. Reference numeral 12 denotes an injection cylinder and has an injection plunger 13 inside. Further, the injection plunger 13 has a through hole 13a having the same cross-sectional shape as the linear or hoop-shaped resin molding material 14, and one end thereof is fitted into the opening 10a of the melting tube 10. An injection nozzle 1 is provided at the tip of the melting cylinder 10.
5. A heat retention heater 16 is provided. The injection plunger 13 is driven by a drive source (not shown), and the injection plunger 13 and the injection plunger 13
The unmolten molding material 14a inside the molten cylinder 10 is injected into the mold (not shown) through the injection nozzle 15.
It is something that is ejected inside. 17 is a bobbin wound with resin molding material, and 18 is a drive roller constituting a material transfer section.

Reference numeral 25 denotes a cylinder made of non-conductive glass or the like through which high-frequency waves can easily pass, and is equipped with a high-frequency dielectric heating means 26 on the outside, and together with the cylinder 25 constitutes a melting cylinder 27, which melts the resin molding material 14. It is. In this case, since a relatively small amount of the resin molding material 20 sent into the cylinder 25 is sequentially melted by high-frequency heating, melting can be performed faster than by a band heater or a screw.

Effects of the Invention As described above, the present invention melts the linear or belt-shaped resin molding material by the high-frequency dielectric heating means while sequentially feeding it into the melting cylinder, so the melting time is shorter than the conventional screw and band heater methods. Can be heated and melted in a short time.

On the other hand, by forming the molding material into a predetermined belt shape or linear shape using an extruder etc. in advance, the kneading of the raw materials and the dispersion of the pigments are better, and the problem of dust that occurs when granular raw materials are used. Since there is no
It can be used next to an assembly line and is suitable for precision molding where dust is a problem.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional in-line screw type injection device, and FIG. 2 is a sectional view of an injection molding device according to an embodiment of the present invention. 12... Injection cylinder, 13... Injection plunger, 13a... Through hole, 19... Feed roller, 26
...High frequency dielectric heating means.

Claims (1)

[Claims] 1. A material transfer part that transfers a linear or belt-shaped resin molding material in the axial direction, an injection plunger having a through hole having a shape substantially the same as the cross-sectional shape of the resin molding material, and one end facing the injection plunger. a melting tube having an open end, an injection nozzle at the other end, and a melting means for melting the resin molding material; An injection molding device constructed by