JPH0138863Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a joining structure between an insulating bushing of a high voltage switch or the like and a molded cone for a lead wire.

Conventionally, as shown in FIG. 1, the method of joining an insulating bushing of a switch or the like and a molded cone for a lead wire is to form an opening 1a at the outer end, an annular internal fold 1b in the shape of a double motor, and An insulating bushing 1 integrally formed with a long external fold 1c is provided so as to cover the internal fold 1b, and a molded cone 2 for the lead wire is provided.
The annular groove 2a provided at the base end of the insulating bushing 1 is brought into contact with the outer end of the internal fold 1b of the insulating bushing 1, and
A conductive rod 3 protruding from the mold cone is inserted into the center hole 1d of the bushing 1 main body from the outside, and the inner end of the conductive rod 3 is inserted into the inner end 1e of the bushing 1 main body.
Screw together the nut 4 that is engaged through a washer or the like,
By tightening this nut 4, the conductive rod 3
The molded cone 2 was brought into pressure contact with the insulating bushing 1 by pulling it inward.

However, when pressing the mold cone 2,
Due to variations in the dimensions of the porcelain when molding the insulating bushings 1, the height of the internal folds 1b differs from bushing to bushing, and the length of the conductive rod 3 protruding inward from the bushing inevitably differs. Not only the tightening amount is different, but also the stopper 3 of the conductive rod 3
Dimensional adjustment was carried out by stacking several packings 5 and adjustment plates 6 between a and the end of the center hole 1d of the bushing 1.

Also, when tightening the nut while adjusting,
If the nut is tightened too much by mistake, the conductive rod will be pulled inward and the airtightness between the mold cone and the bushing body will deteriorate, or the external lead wire crimped to the outer end of the conductive rod may become conductive. There was a fear that it would slip out of the stick.

Therefore, the present invention inserts a part or the whole of the molded cone for the lead wire into the open end of the insulating bushing,
With a simple structure in which the outer circumferential surface of the proximal end extending in the axial direction of the mold cone is joined to the inner circumferential surface of the opening of the insulating bushing, conductivity can be maintained depending on how the mold cone is inserted, even if the dimensions of the bushing differ during manufacturing. Not only can you easily adjust the protruding length of the rod,
To provide a joint structure between an insulating bushing and a molded cone for a lead wire, which has excellent airtightness by increasing the surface contact area between the molded cone and the bushing.

An embodiment embodying the present invention will be described below based on the drawings.

FIG. 2 shows an insulating bushing for a switch embodying the present invention.

An insulating bushing 7 is provided in which the outer end is a cylindrical opening 7a, and the outer end surfaces of annular inner folds 7b and outer folds 7c are integrally formed in a double motor shape so that they are approximately the same length. A bullet-shaped molded cone 8 for an exit line, which has a conical shape and a cylindrical proximal end 8a extending in the axial direction, is inserted, and the proximal end 8a of the molded cone 8 has an outer circumferential surface 8b and the bushing opening. 7a is bonded to the inner circumferential surface 7d with adhesive, and is also protruded from the mold cone 8, with one end connected to an exit line 9 within the mold cone.
A conductive rod 11 crimped 10 is inserted into the center hole 7e of the bushing body from the outside, and the inner end of the conductive rod 11 is engaged with the inner end 7f of the bushing center hole via a washer or the like. Screw together the nut 12,
By tightening the nut 12, the conductive rod 1
1 is pulled inward, and is pressed against the outer end 7g of the center hole of the bushing 7 via the packing 13 by a stopper 11a protruding from the conductive rod 11.

Reference numeral 14 in the figure indicates a pair of grooves (upper and lower in FIG. 2) formed on the inner wall of the center hole 7e,
Both extend over the entire longitudinal direction of the center hole 7e, and are provided on the conductive rod 11 with a detent protrusion 11.
At b, when the nut 12 is tightened, the conductive rod 11 is prevented from idling within the bushing body. Also, 1
Reference numeral 5 denotes a buffer tube installed along the inner walls of the center hole 11 and the groove 14.

In the insulating bushing constructed in this manner, the length of the conductive rod 11 protruding inward from the bushing is determined by the degree of insertion of the molded cone 8 into the bushing, regardless of variations in the porcelain dimensions during the molding of the bushing. dimensions can be easily adjusted,
In addition, since the inner circumferential diameter of the bushing opening 7a and the outer circumferential diameter of the mold cone 8 are designed to be almost the same size, it is possible to connect them with adhesive and extend the mold cone base end 8a in the axial direction. This increases the contact area and ensures sufficient airtightness. Furthermore, not only is airtightness assisted by the packing 13 interposed between the stopper 11a of the conductive rod and the outer end 7g of the center hole, but the mold cone 8 and the bushing 7 are not engaged in the conventional engagement relationship. Therefore, there is no effect on the crimped portion between the conductive rod 11 and the external lead wire due to over-tightening of the nut 12, and there is no risk of it coming off.

The bushing opening 7a and the mold cone 8
To further comment on the fitted state, when the switch is mounted on a pole, the external force in the vertical and horizontal directions applied to the lead wire 9, such as wind pressure, is not directly applied to the conductive rod 11, and this external force is applied to the end of the bushing 7. It is received by the entire inner circumferential surface of the opening 7a in the section, and is not applied to the conductive rod 11 or the connection between the conductive rod and the lead wire, and combined with the flexibility of the mold cone 8 itself, the external force is applied. It also has the advantage that the airtightness is not impaired.

As mentioned above, the present invention has a simple structure in which the mold cone is inserted into the bushing and joined on the entire outer peripheral surface of the mold cone, which not only provides excellent airtightness but also reduces the magnetic dimension during molding of the bushing body. It is possible to obtain a joint structure between an insulating bushing and a molded cone for a lead wire that is easy to assemble and eliminates the drawbacks caused by variations, and can be widely used in industry.

[Brief explanation of the drawing]

FIG. 1 shows a conventional insulating bushing for a switch, etc., and FIG. 2 shows an insulating bushing embodying the present invention. 7... Insulating bushing, 7a... Opening, 7b
...Internal pleats, 7c...External pleats, 7d...Inner peripheral surface, 7e...Center hole, 8...Mold cone, 1
1... conductive rod, 12... nut.

Claims (1)

[Scope of utility model registration request] A stopper 11a prevents rotation of the insulating bushing 7 having a cylindrical opening 7a and a center hole 7e, and engages the center hole 7e from the outside.
In the insulating bushing, in which a conductive rod 11 provided with a conductive rod 11 is fixed by tightening with a nut or the like from the inside of the center hole 7e, the outer end of the conductive rod 11 is provided with the conductive rod 11 and the lead wire 9 inside. A bullet-shaped exit wire mold cone 8 is provided, which is made up of a conical part connecting the two parts and a cylindrical base end part 8a extending in the axial direction. An insulating bushing and lead wire characterized in that it is formed to have approximately the same size as the circumferential diameter, and that almost the entire base end portion 8a is inserted into the opening 7a, and this insertion point is joined with an adhesive. Joint structure with molded cone.