JPH0614375Y2 - Insulation deterioration detector for electric switch - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention (Industrial Application Field) The present invention relates to an electric switch provided with a means for supporting the opening / closing part of an electric circuit and detecting insulation deterioration in an insulator housed in a case. Is.

(Prior art) Since insulators such as insulators in electric circuits may deteriorate due to secular deterioration, external damage or cracks, and cause intermittent ground faults, various detectors detect insulation defects. The insulator is being replaced.

(Problems to be solved by the invention) However, in many cases, switches for overhead lines have an insulator housed in a sealed case. There was a maintenance problem that it could not be done.

It is an object of the present invention to provide an electric switch which can detect a discharge sound due to deterioration of an insulator in the case from the outside of the case in a live state.

Configuration of the Invention (Means for Solving Problems) A through-hole is provided in a case accommodating a plurality of insulators forming an opening / closing part of an electric path, and a spherical portion having a projecting connection terminal is provided at the through-hole. A microphone head is provided, and the spherical portion is supported on a spherical surface of a support which is clamped and fixed to the outside of the case, and the microphone head is rotatably sealed in the case.

(Operation) In the live state of the electric circuit, connect the measuring device to the connection terminal of the microphone head on the outside of the case, and operate the direction of the microphone head from the outside to detect the frequency of the vibration sound wave generated by the discharge of the insulator. An insulator whose insulation has deteriorated can be discriminated from a plurality of insulators with one microphone head.

(Embodiment) Hereinafter, the present invention will be described in detail based on an illustrated embodiment.

As an example of the electric switch in this invention, a line switch is shown in FIG.

This switch for railroad track is equipped with a metal case 3 provided with a mounting member 2 for tightening and fixing to a arm 1 of a utility pole (not shown),
On one side wall of the case 3, bushings 5A, 5B, 5C on the power source side for pulling the three-phase electric lines 4A, 4B, 4C into the case 3 for each phase as opening / closing portions S of the electric line are fixed through the case 3. Bushings 6A, 6B, 6C on the load side for pulling out the three-phase electric circuits 4A, 4B, 4C to the outside of the case 3 are also fixedly provided to penetrate through the case 3 on the opposite side walls. , In the middle,
A movable electrode 8 is provided for each phase on a rotary insulator 7 that is axially supported by the case 3.
A, 8B, 8C are attached and configured, and the rotary insulator 7
When the rotating electrodes are rotated by human power or power, the movable electrodes 8A, 8B, 8C are connected to the fixed electrode members 9A, 9B, 9C and 10A, 10B, 10C connected to the ends of the bushings on the power source side and the load side. Each of them goes in and out to open / close the three-phase electric circuits 4A, 4B, 4C collectively. The case 3 is sealed by a hermetic cover 3a. In the above, each of the bushings 5A to 6C, the rotary insulator 7 and the like are made of a porcelain or an insulator made of synthetic resin. In the present invention, a microphone head 11 for detecting a discharge sound wave generated from the insulator is attached to the bottom surface of the case 3.

As shown in FIG. 2, the microphone head 11 includes a head body 11a and a pair of connection terminals 11b and 11b pulled out from the head body 11a, and the bottom surface side of the head body 11a has connection terminals 11b and 11b. A shaft-shaped holder 12 having a spherical portion 12a formed of hard rubber or plastic that encloses
The connection terminals 11b, 11b are projected at the tip end thereof.

The case 3 has a through hole 3b and a packing groove 3c on the outer periphery thereof.

The through hole 3b is provided with bearing portions 13a and 13b formed so as to match the spherical portion 12a of the holder 12, and a pair of vertically-divided support tools 13 and 13 for slidably supporting the holder 12 are provided. Implant bolt 14 erected on case 3
The other end of the cylindrical rubber bellows 15 that is sealed by being fixed by being fastened via the one end and is further elastically fitted and adhered to the peripheral wall surface of the head body 11a of the microphone head 11. Is sealed between the support groove 13 and the support groove 13 in the packing groove 3c, so that the case 3 is kept airtight.

A recess 13b is formed at an end of the support 13, and a part of the spherical portion 12a and the connection terminals 11b and 11b of the microphone head 11 are housed in the recess 13b so as to project therefrom.

The concave portion 13b is provided with a protective cap 16 and supports 13 and 1
It is screwed onto 3 and sealed. Reference numeral 16a is a knob for attaching and detaching the protective cap 16.

In the electric switch configured as described above, the microphone head 11 is fixedly mounted on the holder 12 having the spherical portion 12a at the mounting portion, and the holder 12 is mounted on the case 3 so that the pair of supporting members 13 and 13 are fixed. Supporting part 13
Since the spherical body portion 12a is supported by a and 13a, the spherical body portion 12a can be freely rotated from the side of the connection terminals 11b and 11b outside the case with the center P of the spherical body portion 12a as a reference within a rotation field at a predetermined inclination angle θ. Since the direction can be changed, it can be held without coming off, and the airtightness is held by the rubber bellows 15, so that the bushings 5A to 6C in the case 3 and the insulator such as the rotary insulator 7 can be protected. Since the microphone head 11 can be arbitrarily deflected while the case 3 is hermetically sealed, sound waves due to discharge of the bushings 5A to 6C as a plurality of insulators can be reliably generated from the outside of the case by one microphone head. Can be detected.

In addition, the discharge vibration of the surrounding gas due to the insulation deterioration of the insulator covers a wide frequency band from the audible frequency to about 100 KHz, but if it is less than 20 KHz, it is mixed because of mechanical vibration of the device side, so it is practical. If it is detected in the ultrasonic region of 40 KHz or higher, it is easy to detect insulation deterioration or identify the degree of insulation deterioration without being affected by external noise.

Therefore, also in the present invention, it is of course effective to use an ultrasonic microphone as the microphone.

In the present invention, by simply connecting the measuring device to the connection terminal of the microphone head outside the grounded case of an electric switch such as an air switch or a gas switch, deterioration of the insulator housed in the case is released. Can be measured without

Effect of the Invention As described in detail above, the present invention detects the electric discharge radio wave of the insulator from the outside of the case safely by operating the microphone head in the case from the outside and housing it inside the case. Since a single microphone head can identify the insulator that has deteriorated from multiple insulators, maintenance work on the line can be performed easily without the need for inspection work within the limited power outage time. effective.

[Brief description of drawings]

1 and 2 show an embodiment in which the present invention is embodied in a line switch, FIG. 1 is a front view of the line switch with a part thereof being cross-section, and FIG. 2 is a cross-sectional view of a main part. 3 ... Case, 5A, 5B, 5C, 6A, 6B, 6C ...
… Bushings, 7 …… Rotating insulators, 8 …… Movable electrodes, 9
A, 9B, 9C, 10A, 10B, 10C ... Fixed electrode part, 11 ... Microphone head, 11b ... Connection terminal, 12 ... Holder, 13 ... Supporting device, 15 ... Bellows.

Claims (1)

[Scope of utility model registration request] 1. A through-hole is provided in a case accommodating a plurality of insulators forming an opening / closing part of an electric path, and a microphone head having a spherical portion with a connecting terminal projected is disposed in the through-hole, An insulation deterioration detecting device for an electric switch, characterized in that a spherical portion is supported on a spherical surface of a support member which is fixed to the outside of the case, and a microphone head is rotatably sealed inside the case.