JPH0143989B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for integrally molding an anode cap used in a high voltage circuit such as a cathode ray tube (hereinafter referred to as CRT) of a television, and a mold for use in this method.

[Technical Background of the Invention] In recent years, the demand for CRTs has been increasing with the development of the electronic industry.

In order to manufacture the anode cap used in the high-voltage circuit of this CRT, conventionally, as shown in Figure 1a, the cap body 1 and the lead wire covering part 2 are integrated by a method such as compression molding or transfer molding of silicone resin. At the same time, as shown in Figure b, a clip 4 for connecting to the CR is fixed to the tip of the lead wire 3, such as a vinyl chloride resin coated wire, with flux, and a metal cap 5 is attached to the tip. After tightening and manufacturing the assembled lead wire 6, as shown in FIG. The method used was to pull the clip 4 and attach it to a predetermined position on the cap body 1, as shown in FIG.

[Problems with Background Art] However, in this method, a large amount of labor and time is required for assembly work, which has been a major obstacle to promoting rationalization and labor saving in the electronic component industry.

For this reason, it is conceivable to directly injection mold the cap body 1 and the lead wire covering part 2 on the outer periphery of the lead wire 3, but in this case, the base of the lead wire 3 will be in contact with a high-temperature mold for a long time. However, there were problems in that the contact portion was deformed and the base of the lead wire was bent.

[Object of the Invention] The present invention has been made in response to the above-mentioned circumstances, and has a method that does not cause deformation of the sheathing of the inserted lead wire or bending of the base of the lead wire, and The object of the present invention is to provide a method for quickly and easily integrally molding an anode cap, and a mold for use in this method.

[Summary of the Invention] That is, the method for integrally molding an anode cap of the present invention comprises: an outer mold having a hemispherical recess for molding the outer surface of the cap body and a tubular passage for molding the lead wire covering portion; The cap body and the lead wire covering part are formed using a mold consisting of a hemispherical convex part that fits into the concave part to form the inner surface of the cap body, and an inner mold having a clip insertion part provided in the convex part. In an anode cap molding method in which a clip is fixed to one end of the lead wire, the clip is inserted into the clip insertion part of the inner mold, and the lead wire is passed through a tubular passage of the outer mold. Furthermore, a heat insulating member is inserted from the outside to seal the gap between the tubular passage of the outer mold and the lead wire, and the lead wire is held in a straight line behind the heat insulating member while being inserted into the mold. It is characterized by press-fitting a thermosetting resin into the cap body, and the mold used therein is an outer mold having a hemispherical recess for molding the outer surface of the cap body and a tubular passageway for molding the lead wire covering part. A molding die consisting of a mold, an inner mold having a hemispherical protrusion that is fitted into the recess of the outer mold to form the inner surface of the cap body, and a clip insertion part provided in the protrusion, the outer mold A step part extending outward from the tubular passage is formed in the tubular passage, and a two-part sealing member made of a heat insulating material and having a lead wire lead-out part is inserted and fixed into the step part, and from the lead wire lead-out part. It is characterized in that lead wire support members having lead wire gripping portions are disposed at intervals on the same axis.

[Embodiments of the Invention] Examples of the integral molding method and molding die of the present invention shown in the drawings will be described below.

FIG. 2 is a longitudinal sectional view showing a molding die according to an embodiment of the present invention, FIG. 3 is a perspective view thereof in the direction of arrow A, and FIG. 4 is a front view showing the lead wire support member of FIG. 2. be. Note that in FIG. 2, parts common to those in FIG. 1 are given the same reference numerals.

In FIG. 2, reference numeral 10 indicates the entire molding die of this embodiment.

This molding die 10 is separable in a vertical plane along the axis of the lead wire sheathing part, which has a hemispherical recess 11 for molding the outer surface of the cap body and a tubular passage 12 for molding the lead wire sheathing part. External mold 1
3, an inner mold 16 having a hemispherical protrusion 14 that fits into the recess 11 of the outer mold 13 to form the inner surface of the cap body, and a clip insertion part 15 provided in the protrusion 14. It is configured.

The clip insertion portion 15 is a truncated cone-shaped bifurcated conical member having a conical hole 17 bored in a hemispherical convex portion 14 and clip gripping grooves 18a and 18b on opposing surfaces fitted into the conical hole 17. 19.

This conical member 19 is driven in the vertical direction by a knock pin 20, and is configured to be able to grip and release the clip 4 at the tip of the lead wire 3 inserted into the cavity.

However, in this embodiment, a step 21 is formed at the end of the tubular passage 12 of the outer mold 13 and extends outward from the tubular passage 12, and the step 21 has two sections as shown in FIG. A split sealing member 22 is fitted and fixed with screws 23.

This two-part sealing member 22 is made of a heat insulating material such as Teflon or a glass fiber laminate, and has a lead wire lead-out groove 24 formed on the opposing surface. In addition,
This two-split sealing member 22 is not directly fitted to the stepped portion 21, but is fixed to another two-split metal member to fit and fix this two-split metal member to the stepped portion 21. Good too.

Furthermore, behind the inner mold 16, as shown in FIG. Like, bolt 2
It is fixed by 7. 28 is a bolt hole. This support member 26 may be made of metal, but is more preferably made of a heat insulating material.

Further, a gate 29 is provided between the outer mold 13 and the inner mold 16 for injecting a silicone resin molding material into the cavity of the molding die 10.

Note that each of the two halves in the above embodiments may be a divided body divided into three or more pieces.

In the forming method of the present invention, such a molding die 1
This is done using 0 as follows.

First, with the outer mold 13 separated into left and right sides, the lead wire 3 with the clip 4 fixed to the tip is fitted into the lead wire gripping part 25 of the support member 26, and the clip 4 is gripped by operating the dowel pin 20. Groove 1
8 to hold it.

Next, the outer mold 13 is combined to form the lead wire lead-out groove 2.
4 to hold the lead wire 3. At this time, the lead wire 3 should be in a completely horizontal state.

Thereafter, a silicone resin molding material 30 is injected into the cavity of the molding die 10 through the gate 29, and is thermally cured to form the cap body 1 and the lead wire covering portion 2.

According to this method, silicone resin molding material 3
During the press-fitting and heat curing of 0, the non-buried part of the lead wire 3 coating near the cavity is almost horizontal at two points: the two-part member made of heat insulating material and the support member placed at a distance from the two-part member. Since it is held in
There is no possibility that the sheathing of the lead wire 3 will soften or uneven thickness will occur in the lead wire sheathing portion.

[Effects of the Invention] As is clear from the above description, according to the first aspect of the present invention, there is no softening or deformation of the lead wire coating, and there is no uneven thickness in the silicone resin molded body constituting the cap body. The anode cap can be integrally molded with good workability and in a short time.

Moreover, according to the molding die of the second invention, the first
invention can be effectively realized.

[Brief explanation of drawings]

Figures 1 a to d are views showing a conventional anode cap assembly method, Figure 2 is a longitudinal sectional view showing the molding die of the present invention, and Figure 3 is an enlarged view of direction A in Figure 2. FIG. 4 is a partially cutaway perspective view and a front view of the support member. 1...Cap body, 2...Lead wire covering part,
3...Lead wire, 4...Clip, 10...Forming mold, 11...Semispherical recess, 12...Tubular passage, 13...Outer mold, 14...Protrusion, 15...Clip insertion Part, 16...inner mold, 19...conical member,
20...Knock pin, 21...Step part, 22...Sealing member, 24...Lead wire lead-out part, 25...Lead wire gripping part, 26...Supporting member, 29...Gate, 30...Silicone resin Molding material.

Claims (1)

[Scope of Claims] 1. An outer mold having a hemispherical recess for molding the outer surface of the cap body and a tubular passageway for molding the lead wire covering portion following the hemispherical recess, and a cap body that is fitted into the recess of the outer mold. An anode in which a cap body and a lead wire covering part are injection molded onto the outer periphery of a lead wire using a molding mold consisting of a hemispherical convex part that molds the inner surface and an inner mold having a clip insertion part provided in the convex part. In the cap molding method, a clip is fixed to one end of the lead wire, the clip is inserted into the clip insertion portion of the inner mold, the lead wire is guided to the outside through a tubular passage of the outer mold, and the lead wire is guided outside through the tubular passage of the outer mold. A heat insulating member is inserted from the outside to seal the gap between the passage and the lead wire, and the lead wire is held in a straight line behind the heat insulating member.
An anode cap integral molding method characterized by press-fitting a thermosetting resin into a mold. 2. An outer mold having a hemispherical recess that forms the outer surface of the cap body and a tubular passageway that molds the lead wire covering portion that follows this, and a hemispherical mold that fits into the recess of the outer mold to form the inner surface of the cap main body. In a molding die consisting of an inner mold having a convex portion and a clip insertion portion provided in the convex portion, a step portion extending outward from the tubular passage is formed in the tubular passage of the outer mold, and a step portion is formed in the step portion. A two-part sealing member made of a heat insulating material and having a lead wire lead-out part is inserted and fixed, and a lead wire support member having a lead wire grip part is arranged at a distance from the lead wire lead-out part on the same axis. A mold for integrally molding an anode cap. 3. The mold for integrally molding an anode cap according to claim 2, wherein the outer mold is separable along the axis of the lead wire covering portion.