JPS6134657Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in bushings for electrical equipment.

As shown in FIG. 1, the structure of a conventional bushing of this type includes a cylindrical support fitting 5 and this support fitting 5.
Air side and oil side insulator pipes 4a arranged at both ends of the
4b, a central conductor 1 having an insulating layer 1a around it is passed through, and a clamp 2 is provided at the end of the oil submerged insulator tube 4b, and an expansion chamber 3 is provided at the end of the air insulator tube 4a. The repulsive force of the spring 6 installed in the expansion chamber 3 tightens each part via the center conductor 1, compressing the gasket inserted between each part and making the whole into a sealed container with insulating oil sealed inside. It was composed of If a bushing with this structure is attached to an oil-filled electrical device such as a transformer and the insulator 4a on the air side is damaged due to a strong shock such as an earthquake or a flying object collides with the insulator, the damage will occur as shown in Figure 2. As shown in , not only the insulating oil in the bushing but also the insulating oil of the equipment leaks out through the space between the support fitting 5 and the center conductor 1 as shown by the arrow. This is due to the breakage of the air insulator tube 4a, causing the spring 6
This is because the repulsive force of the oil-submerged insulator 4b disappears, and the oil-filled side insulator tube 4b falls into the tank 7 together with the center conductor 1, causing the equipment to lose its sealed state. Such an accident has the disadvantage that flammable insulating oil leaks out of the equipment, which increases the secondary damage, and also causes damage to the inside of the equipment due to the falling of the center conductor 1 and the bushing tube 4b of the bushing. There is. In order to prevent such accidents, insulator pipe 4 on the oil side
A structure in which metal fittings are attached to both ends of b with cement and fixed to supporting metal fittings or clamps by bolting has been adopted in the past, but the dimensions become larger and the dimensions of the equipment must be increased accordingly. However, the disadvantage was that it resulted in an uneconomical structure.

This invention improves the above-mentioned drawbacks. Even if the air side insulator is damaged, the center conductor and the oil side insulator will not fall, and therefore the insulation of the main body of the equipment can be improved. The object is to provide a bushing that does not cause oil spills.

An embodiment of the present invention will be described below with reference to FIGS. 3 to 7.

FIG. 3 is a partial sectional view of the oil submerged insulator tube portion of the present invention. At the upper part of the oil side insulator pipe 4b, there is a fourth
As shown in the partial cross-sectional view of the figure, a convex portion 12 is formed over the entire circumference on the end surface side, and a plurality of folds 17 are provided on the lower side. This oil side insulator pipe 4b
are completely assembled in a so-called center clamp structure together with an air side tube (not shown), an expansion chamber, a spring, a support fitting 5, a clamp 2; and a center conductor 1, and then a small tape 8' as shown in FIG.
An insulating tape 10 consisting of an insulating tape 8'' and a connecting tape 9 is wrapped around the upper joint of the insulator tube 4b, a small tape 8' is wrapped around the body of the support fitting 5, and a small tape 8'' is wrapped under the protrusion 12 of the insulator tube 4b. Wrap each one so that they are covered.
The small tape 8' is overlapped at the joint 14 on the circumference, and the small tape 8'' is similarly overlapped at the joint 15 on the circumference and bonded by heating.The connecting tape 9 is set to a length in advance as shown in FIG. A ring is formed at both ends through which the small tapes 8' and 8'' pass, and an overlapping adhesive part 16 is formed at the center. Similarly for the lower part of the insulator tube 4b, the insulator tube side is 1 from the bottom.
Wrap a small piece of tape 8' over the concave part 13 between the two pleats, and wrap a small piece of tape 8'' over the convex part 13 of the clamp 2, which is partially shown in cross section in FIG. After connecting the upper and lower parts of the pipe 4b to the support fitting 5 and the clamp 2 using insulating tape 10, tightening tape 11 is applied to further strengthen the connection between the two.
is wrapped around the part where the connecting tape 9 stands out from the parts in the middle and tightened, and the connecting tape 9 is pulled in the direction of the center axis of the bushing so that the entire part is firmly tightened and adhered. The number of connecting tapes 9 is determined so that they are evenly spaced on the circumference. Note that the tape is preferably a tape made of glass fiber impregnated with polyester resin or epoxy resin, and is heated to about 130° C. with a heater to harden and bond.

FIG. 8 shows another embodiment of the present invention, in which a ring 18 is provided on the body side instead of the tightening tape, and a small tape 8' is wound around this ring 18, and an adjustment bolt 19 is turned to tighten the ring 18. By separating it from the insulator tube 4b, the connecting tape 10 is tightened to strengthen the contact between the support fitting 5 and the insulator tube 4b. With this configuration, the oil-submerged insulator tube 4b is fixed to the support fitting 5 attached to the tank with the insulating tape 10, and the center conductor 1 is fixed to the oil-submerged insulator tube 4b via the clamp 2 with the insulating tape 10.
Even if the air side insulator pipe is damaged, the center conductor 1 and the oil side insulator pipe 4b
Since the device does not fall, it is possible to maintain the sealed state of the device. Therefore, there is no damage to the inside of the device, and the insulating oil inside the device does not leak out to the outside of the device, thereby preventing secondary disasters. Insulating tape 10
The bushing can be installed without lengthening or enlarging the support fitting 5 or the oil submerged insulator pipe 4b, and therefore does not cause the bushing to become large.

As described above, according to the present invention, the insulator tube can be made to have the necessary minimum effective length, and its outer diameter is almost the same as the diameter of ordinary insulator tubes of this type.
Even if the insulator tube on the air side of the bushing breaks, the insulating oil in the equipment body will not leak outside, and the center conductor of the bushing and the insulator tube on the oil side will not fall into the tank, resulting in accidents caused by secondary disasters. This has excellent practical effects such as being able to prevent the spread of.

[Brief explanation of the drawing]

Figure 1 is a partial cross-sectional view of a conventional bushing;
The figure is a schematic diagram showing a state in which the oil-submerged side insulator pipe is damaged and the insulating oil in the device body leaks out to the outside with the bushing attached to the device. Figure 3 is an example of an embodiment of the present invention. 4 is a partial sectional view of the upper end of the insulator tube shown in FIG. 3, FIG. 5 is a partial sectional view of the clamp shown in FIG. 3, and FIG. 6 is a partial sectional view of the insulating tape according to the present invention. A front view, FIG. 7 shows a side view of the connecting tape of FIG. FIG. 8 shows another embodiment of the invention. DESCRIPTION OF SYMBOLS 1... Central conductor, 2... Clamp, 3... Expansion chamber, 4a... Air side insulator tube, 4b... Oil submerged side insulator tube, 5... Supporting metal fittings, 6... Spring, 7...
Tank, 8', 8''...Small tape, 9...Connecting tape, 10...Insulating tape, 11...Tightening tape,
12...Insulator tube convex part, 13...Clamp convex part, 1
4, 15, 16... Joining overlapped portion, 17... Insulator tube fold, 18... Ring, 19... Adjustment bolt.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A cylindrical support fitting that surrounds a central conductor that is attached to a tank and has an insulating layer around it, and an air side holder that is disposed at one open end of the support fitting. A pipe and an oil-submerged side pipe disposed at the other open end of the support fitting are sandwiched between a clamp and an expansion chamber, and are tightened together via a spring provided in the expansion chamber and the central conductor. , A bushing characterized in that the oil submerged side insulator pipe and the support fittings and clamps in contact with both ends thereof are each fixed with insulating tape. (2) Practical use characterized in that the insulating tape consists of two small tapes attached to the oil submerged insulator pipe side and the support metal side or clamp side, and a plurality of connecting tapes connecting the two small tapes. Bushing as described in paragraph (1) of the claims for patent registration.