JPH0120776Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an anode cap used in a high voltage circuit of a cathode ray tube (hereinafter referred to as CRT) of a television.

[Technical background of the invention] In recent years, with the development of the electronics industry, the demand for CRTs has been increasing.

Conventionally, as shown in Fig. 1, the anode cap used in the high-voltage circuit of the CRT is made of a cap body 1 made of silicone resin, etc., with a guide path 2 and a clip 3 at the tip for contacting the CRT. A structure in which a synthetic resin-coated lead wire 4 fixed with a wire etc. is attached is used.

The method for manufacturing such an anode cap generally involves molding the cap body 1 and fixing the clip 3 to the synthetic resin-coated lead wire 4 in separate steps, and then assembling the cap body 1 into the conduit 2 from the inside. The lead wire 4 is inserted and the free end of the lead wire is pulled firmly until the clip 3 is in place.

[Problems with the Background Art] However, with such a method, not only is it time-consuming and labor-intensive to manufacture, but the cap can be assembled using only the tightening force based on the elasticity of the silicone resin, etc. that constitutes the cap body 1 of the obtained anode cap. Since the main body 1 and the covering of the lead wire 4 are sealed, it is difficult to maintain sufficient adhesion, and there is a problem in that leaks are likely to occur from the interface between these parts.

[Purpose of the invention] The present invention was made to solve these problems, and the object is to provide an anode cap that has excellent adhesion between the cap body and the lead wire coating, and has no leakage from the interface between them. purpose.

[Summary of the invention] That is, the present invention comprises a synthetic resin coating having good adhesion to the molding material and the synthetic resin coating on the inside of a cap body made of a synthetic resin molding material. This anode cap is characterized by being integrally molded with a lead wire inserted.

In this invention, the synthetic resin molding material that makes up the cap body is usually a molding material that has good electrical insulation and elasticity, such as silicone resin, and the synthetic resin that makes up the lead wire coating is polychlorinated resin. Vinyl resins, especially polyvinyl chloride resins blended with flame retardants, are used.

In addition to silicone resin, synthetic resin materials that are provided on the lead wire coating and have good adhesion to both of them include vinyl chloride-vinyl acetate copolymer, silicone primer, polyurethane adhesive, epoxy adhesive, and Examples include hot melt adhesives.

In the present invention, these synthetic resin materials are coated on the coating of the portion of the lead wire that is inserted into the cap body to form an adhesive coating, or a tube made of silicone resin is coated on the coating of the portion. Insert the fitted part into a predetermined part of the mold having a molding space corresponding to the cap body,
By injecting and filling the silicone resin molding material into the cavity, an anode cap in which the cap body and the lead wire coating are completely integrated via the aforementioned synthetic resin coating can be obtained.

[Embodiments of the invention] Examples of the invention shown in the drawings will be described below.

FIG. 2 is a partial vertical sectional view of an embodiment of the present invention.

In the figure, reference numeral 5 indicates a cap body made of silicone resin, and this cap body 5 is molded by a known method such as injection molding or transfer molding with a lead wire 6 coated with flame-retardant polyvinyl chloride resin inserted. .

Moreover, on the insert part of the lead wire 6 coating, a synthetic resin that has good adhesion to both the silicone resin that makes up the cap body 5 and the flame-retardant polyvinyl chloride resin that makes up the lead wire 6 coating is used. The cap body 5 and the lead wire 6 are integrally molded with good adhesion through this adhesive coating 7. Note that the reference numeral 8 in FIG. 2 indicates a clip fixed to the tip of the lead wire 6.

In the anode cap constructed in this manner, the cap body 5 and the covering of the lead wire 6 are completely integrated, so no leakage occurs from the interface between them, and the withstand voltage characteristics are extremely excellent. .

In other words, the withstand voltage of an anode cap that is integrally molded by inserting the flame-retardant polyvinyl chloride resin-coated lead wire as it is inside the cap body made of silicone resin without providing such an adhesive coating 7 has a withstand voltage of 30 KV or less. On the other hand, for example, an anode cap that is integrally molded by inserting a lead wire with a silicone primer coated on a flame-retardant polyvinyl chloride resin coating and forming a coating 7 has a withstand voltage of 58 KV, and it has a withstand voltage of 58 KV even after being sprayed with salt water. Almost no change is observed.

Also, when a silicone resin tube is fitted instead of applying a silicone primer or an adhesive film 7 is formed by coating with a silicone resin, the withstand voltage values of the obtained anode caps are 60KV and 56KV, respectively. Therefore, there was almost no change in the withstand voltage value after salt water fog in either case.

In each of the above embodiments, the withstand voltage was measured by forming a pair of annular electrodes 9 on the outer periphery of the base of the cap body 5 into which the lead wire 6 was inserted, as shown in FIG. This was done by applying a voltage between the conductors of the lead wire 6 and measuring the voltage at which dielectric breakdown occurred.

[Effects of the Invention] As is clear from the above description, the anode cap of the present invention has good adhesion between the lead wire coating and the cap body, and is extremely excellent in electrical properties including withstand voltage properties.

[Brief explanation of drawings]

FIG. 1 is a partial vertical cross-sectional view of a conventional anode cap, and FIG. 2 is a partial vertical cross-sectional view of an embodiment of the present invention.
FIG. 3 is a partial vertical cross-sectional view showing a method for measuring withstand voltage in an example. DESCRIPTION OF SYMBOLS 1, 5... Cap body, 3, 8... Clip, 4... Synthetic resin coated lead wire, 6... Flame retardant polyvinyl chloride resin coated lead wire, 7... Adhesive coating, 9... Electrode.

Claims (1)

[Scope of utility model registration request] A lead wire comprising a synthetic resin coating and a synthetic resin coating having good adhesion to the molding material and the synthetic resin coating is inserted into a cap body made of a synthetic resin molding material and integrally molded. An anode cap characterized by: