JPH07296929A - Integral molding method for high voltage plug - Google Patents

Abstract

PURPOSE:To prevent short-circuiting, poor insulating, etc., and generate a good water leak preventing effect by compressing an upper and a lower core through utilization of the pressures given by an upper and a lower die. CONSTITUTION:A plug terminal 18 is connected with a high voltage cord 14, which penetrates a core set 20 to form a consolidated structure, and this is introduced into a cavity 32a formed by an upper and a lower die 30, 32 and is compressed. Thereby the cord 14 is compressed within the core set 20, and the insulative covering of the cord 14 is put in pressure contact with screw fit grooves 22a, 24a provided in the dies 22, 24. This provides a high voltage plug 12 which is perfectly free from the risk of cord twisting, slipping off, etc., in the molding process.

Description

DETAILED DESCRIPTION OF THE INVENTION "Aim" (Industrial field of application) The present invention relates to a method of integrally molding a high-voltage plug, and more particularly, to a power cord of a desired electric device, twisting of the cord, and disconnection of the cord. , A method of integrally molding a high-voltage plug that prevents occurrence of short circuits, insulation defects, and the like. (Prior Art) Since a high-voltage connector, a plug, etc. for a power supply of a high-voltage cord, which is conventionally provided in an electric device, is molded with a material different from the cord, the degree of adhesion between the cord and the material is low, and In many cases, the function as a high-voltage connector or plug cannot be fulfilled due to twisting, cord omission, short circuit, poor insulation, etc. (Problems to be solved by the invention) In order to eliminate the drawback, conventionally, as shown in FIG. 6, a part to be the body of a connector or a plug is partially concave around the outer periphery of an insulating coating of a power cord. After cutting, it is introduced into a mold, and a molten synthetic resin is injected and molded to prevent the power cord from twisting or coming off. However, since the recessed insulating coating is thin, a defect such as impairing the insulating property at that portion cannot be avoided. Further, a method of winding a metal member around a portion which should be a main body of a connector or a plug has been implemented, but this is also troublesome. (Means to be Solved by the Invention) The present invention is intended to eliminate the above-mentioned drawbacks, and its gist is to provide a threaded groove on the inner periphery and a plurality of protrusions for injecting a molten synthetic resin solution on the outer periphery. A substantially semi-cylindrical upper core having a guide pin in the longitudinal direction of the dividing surface, a screw groove corresponding to the upper core, an inner periphery, a plurality of projections for inflowing the molten synthetic resin liquid, and a division. In a core set consisting of a substantially semi-cylindrical lower core in which guide and pin fitting holes are bored at the guide and pin corresponding positions in the longitudinal direction of the surface, a high voltage cord with the required plug terminals connected. Through the core set, and forming a required gap in the dividing surface of the upper and lower cores into which the guide pins of the upper core are fitted in the guide pin fitting holes of the lower core. And the core set and the high voltage cord into the upper and lower molds, and these upper and lower molds are closely attached. The process includes the steps of injecting a required molten synthetic resin into the upper and lower molds, and releasing the molten synthetic resin after cooling and curing, and the upper and lower cores are formed by using the pressure of the upper and lower molds. It is an integral molding method of a high voltage plug that compresses. [Structure] (Example) An example of a high-voltage plug according to the present invention will be described with reference to the drawings. In FIGS. 1 to 5, a plug terminal 19 is connected to the tip of a high-voltage cord 14 (for example, a television power cord) by crimping or soldering. A screw groove 22a is formed on the inner periphery of the substantially semi-cylindrical upper core 22, a plurality of protrusions 22b are provided on the outer periphery thereof at regular intervals, and a guide pin 22d is provided vertically at the center of the divided surface 22c in the longitudinal direction. . As shown, the portion of the longitudinal dividing surface 22c where the guide pin 22d is provided partially bulges to reinforce. Similarly, a threaded groove 24a is formed on the inner circumference of the substantially semi-cylindrical upper core 22, and a plurality of projections 2 are formed on the outer circumference thereof at regular intervals.
4b is provided, and fitting holes 24d for the guide pins 22d are formed in the upper core 22 at positions corresponding to the guide pins 22d at the center of the longitudinal dividing surface 24c. The periphery of the fitting hole 24d is expanded to reinforce it. The height of the vertical pin 22d provided in the substantially semi-cylindrical upper core 22 and the depth of the fitting hole 24d formed in the lower core 24 are as shown in FIG. To the lower core 24 and the vertical pin 22d into the fitting hole 24d.
When fitted inside, the former longitudinal dividing surface 22c and longitudinal dividing surface 24c do not come into close contact with each other, and a constant gap is provided on these surfaces so that the injected synthetic resin melts into the upper and lower cores 2.
It is designed to be easily guided into the core set 20 composed of 2, 24. In the curved portion of the lower core 24 of the core set 20, guide the required portion of the high voltage cord 14 described above, align the upper core 22 with the lower core 24, and attach the latter guide pin 22d. The former is fitted into the fitting hole 24d to be integrated. The high voltage cord 14 and the core set 20 are guided into the cavity 32a of the lower mold 32 and fixed as shown in FIG. 3, and the upper mold 30 is fitted to the lower mold 32. The latter positioning pin 32b is fitted into the former fitting hole (not shown) to be integrated, and the molten synthetic resin is injected and injected from the injection hole 32c. The molten synthetic resin injected is
It is thickly inserted at high temperature (about 300 ° C.) and high pressure (about 70 kg / 1 cm ² ). If the resin is cooled and cured and then released from the mold, the fourth,
A high voltage plug 12 as shown in FIG. 5 is obtained. Since the upper and lower cores 22 and 24 of the core set 20 are formed with a plurality of protrusions 22b and 24b, respectively, the molten synthetic resin injected from the injection hole 32c is guided into the cavity of the mold without any trouble. I can do things. [Operation and Effect] As described above, the high voltage cord 14 to which the plug terminal 18 is connected is penetrated into the core set 20 and integrated into the cavity 32a of the upper and lower molds 30 and 32. The high voltage cord 14 is compressed in the core set 20, and the insulation coating of the high voltage cord 14 is pressed against the screw grooves 22a and 24a of the upper and lower cores 22 and 24, respectively. Therefore, it is possible to obtain the high-voltage plug 12 in which twisting of the high-voltage cord 14 and disconnection of the cord are completely eliminated in the molding process. Since the insulation coating is not partially cut like the known example, it prevents the occurrence of short circuits, insulation defects, etc.
Further, the effect of preventing water leakage can be obtained. Therefore, the molding method becomes easy and low-cost manufacturing becomes possible.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of upper and lower cores and a high voltage cord used for molding a high voltage plug by the method according to the present invention, and FIG. FIG. 3 is a perspective view showing a state where the core set that has penetrated is integrated, FIG. 3 is a perspective view of upper and lower molds for guiding the core set shown in FIG. 2, and FIG. 4 is a high voltage molded by the method of the present invention. FIG. 5 is a perspective view of the plug, FIG. 5 is a perspective side view of FIG. 4, and FIG. 6 is a partial perspective view showing a state in which a portion to be the body of the plug is partially cut around the outer periphery of the insulation coating of the power cord. Is. 12 ... High voltage plug; 14 ... High voltage cord; 18 ... Plug terminal; 20 ... Core set; 22 ... Upper core; 22a ... Screw groove; 22b ... -Molded synthetic resin inflow projection; 22c ... Dividing surface; 22d ... Guide pin; 24 ... Lower core; 24a ... Threaded groove; 24b ... Molten synthetic resin inflow projection; 24c ... Dividing surface; 24d ... Guide pin fitting hole; 30 ... Upper mold; 32 ... Lower mold.

Claims (1)

Claims: (1) A substantially semi-cylindrical upper core having a screw groove on the inner periphery, a plurality of protrusions for injecting the molten synthetic resin liquid on the outer periphery, and a guide pin in the longitudinal direction of the dividing surface, Corresponding to the upper core, there are threaded grooves on the inner periphery, a plurality of projections for inflowing the molten synthetic resin liquid on the outer periphery, and guide / pin fitting holes at the guide / pin corresponding positions in the longitudinal direction of the dividing surface. A core set consisting of a substantially semi-cylindrical lower core having holes formed therein; a high voltage cord connected to a required plug terminal is pierced through the core set, and the guide pin fitting of the lower core is performed. The guide of the upper core in the fitting hole
Forming a required gap on the split surfaces of the upper and lower cores fitted with pins; guiding the core set and the high voltage cord into the upper and lower molds, and closely adhering these upper and lower molds; A step of injecting a required molten synthetic resin into the upper and lower molds; a step of cooling the molten synthetic resin, and removing it after curing, and compressing the upper and lower cores by using the pressure of the upper and lower molds. High voltage plug integrated molding method.