JPH017970Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial field of application The invention relates to a box-shaped high-voltage cutout with a lightning protection unit.

Prior Art Conventionally, a high-voltage cutout equipped with a lightning arrester unit has been proposed in which the lightning arrester unit is housed within the main body insulator. However, moisture intrudes into the lightning arrester unit and causes it to deteriorate, causing creepage of the element, and when it is no longer possible to cut off the follow-on current during operation, the internal pressure of the element rises, damaging the main body insulator and causing large-scale damage. There was a risk that it would lead to a public disaster.

Purpose of the invention The purpose of this invention was to address the above-mentioned problems and to simplify the support structure of the lightning arrester unit so that the lightning arrester unit can be easily assembled into a box-shaped high-voltage cutout. It also prevents the main insulator from being damaged when the non-linear resistance element deteriorates, causing element creepage, or when the internal pressure of the element increases due to failure of follow-on current interruption during operation. The object of the present invention is to provide a high-voltage cutout with a lightning protection unit that reduces public disasters as much as possible.

Composition of the Device In order to achieve the above-mentioned object, this device has a lightning arrester unit mounting portion consisting of a cylindrical recess at the lower part of the back side of the main insulator and an annular fitting protrusion provided at the inner bottom of the cylindrical recess. A through hole communicating with the load-side electrode chamber is bored in the lightning arrester unit mounting part, and when installing the lightning arrester unit formed with an insulating mold to the mounting part, a hole extending from the load-side fixed electrode is formed. The charging side electrode of the lightning arrester unit that passes through the through hole is attached to the conductor piece by screwing from the outside of the main insulator, and an annular fitting groove is provided at the base end of the lightning arrester unit. is closely supported by the fitting protrusion and electrically connected to expose most of the lightning arrester unit to the outside, through a through hole provided in the insulation protection cap that covers the ground side electrode of the lightning arrester unit. The gist is that the end of the grounding fitting extending from the back surface of the main body insulator is placed opposite to the end of the grounding fitting with a predetermined discharge gap.

Embodiment Hereinafter, an embodiment embodying this invention will be described with reference to the drawings. Inside the box-shaped main body insulator 1, a pair of power supply side electrode chambers 3 and load side electrode chambers 4 are divided vertically by partition walls 2. It is formed. In the electrode chambers 3 and 4 on the power supply side and the load side, arc extinguishing chambers 7 and 8 are fixedly installed together with the fixed electrodes 5 and 6, respectively. Each terminal is provided with a terminal to be connected to the side track.

A lid insulator 9 is pivotally attached to the ventral side of the main body insulator 1 so as to be openable and closable, and on the inside of the lid insulator 9 there are power supply side and load side insulators protruding from each of the fixed electrodes 5 and 6. Fuse tube 12 with contact blades 10, 11
is attached replaceably.

Further, because of the structure of this type of box-shaped cut-out switch, the lower part of the dorsal side of the main body insulator 1 is generally formed to have a shorter vertical length than the lower part of the ventral side. A lightning arrester unit attachment part 13 is recessed in the lower surface of the back side of the main body insulator 1, and is made up of a cylindrical recess and an annular fitting protrusion provided at the inner bottom of the cylindrical recess. An annular fitting protrusion 13a is formed therein. A through hole 1 communicating with the load-side electrode chamber 4 is provided at the center of the inner bottom of the lightning arrester mounting portion 13.
4 is formed.

The supporting metal fitting 15 for fixing the load-side fixed electrode 6 to the load-side electrode chamber 4 has its proximal end fixed to the bottom of the electrode chamber 4 with an adhesive 16, and there is a space between the tip and the load-side fixed electrode 6. One end of the conductor piece 18 is connected. The other end of the conductor piece 18 extends through the adhesive portion so as to correspond to the through hole 14.
Note that 19 is an elastic regulating member fitted into the deepest bottom of the load-side electrode chamber 4 corresponding to the through hole 14, and when the base end of the support fitting 15 is fixed with adhesive, the adhesive point is It is designed to be regulated and buried with the same adhesive 16.

A lightning arrester unit 21 is provided in the mounting portion 13, and the charging side electrode 20 thereof is electrically connected to the other end of the conductor piece 18 by screwing from the outside of the main insulator 1 through the through hole 14, and is supported and fixed. is attached.

To explain the lightning arrester unit 21, the lightning arrester unit 21 has a non-linear resistance element 23 having an annular end face, which is made mainly of zinc oxide (ZnO) with the addition of small amounts of several kinds of metal oxides, and is fired and has excellent non-linear resistance characteristics. A plurality of pieces are formed and stacked on each other, and the center hole 2
An insulating rod 25 made of synthetic resin, one end of which is screwed to the ground electrode 24, is inserted through the insulating rod 3a.
The other end is screwed onto the charging side electrode 20 to support the space between the electrodes 20 and 24, and the nonlinear resistance element 23 is held between the electrodes 20 and 24. Therefore, the nonlinear resistance elements 23 at both ends are electrically connected to both electrodes 20 and 24, respectively.

After the non-linear resistance element 23 is coated with a coating member (not shown) such as silicone rubber, the outer periphery of the non-linear resistance element 23 and the outer periphery of the central part of the charging side electrode 20 are coated with thermosetting epoxy resin. Insulating mold 27 is processed. The proximal end surface of the insulating mold 27 is formed to be able to fit tightly into the mounting portion 13, and has an annular fitting groove 27a closely fitted to the fitting protrusion 13a.

The tip of the insulating mold 27 is formed to extend into a cylindrical shape so as to cover the ground-side electrode 24, and the ground-side electrode 24 is disposed within the tip of the insulating mold 27.
An insulating protective cap 28 tightly fitted around the outer periphery is adhered with an adhesive such as epoxy resin while maintaining watertightness.

A lightning arrester unit 21 is constituted by the non-linear resistance element 23, the charging side electrode 20, the grounding side electrode 24, the insulating rod 25, the protective cap 28 and the insulating mold 27. Note that when attaching the lightning arrester unit 21 to the mounting part 13 of the main body insulator 1, the insulation mold 2
Adhesive is injected between the base end surface of 7 and the mounting portion 13 to maintain watertightness.

Therefore, as shown in the figure, the lightning arrester unit 21 is installed so that most of it is exposed from the main insulator 1, and when it is installed, it can be easily attached by screwing from the outside of the main insulator 1. can.

A support metal fitting 31 for supporting a cutout with respect to a cross arm 30 is fixed to the back surface of the main body insulator 1, and a grounding metal fitting 32 is integrally formed at the tip of the support metal fitting 31. A protective cap 2 is attached to the tip of the grounding fitting 32 for the grounding side electrode 24 of the lightning arrester unit 21.
They extend from the back surface of the main insulator 1 so as to be opposed to each other with a predetermined discharge gap through a through hole 28a provided at the center of the insulator 8.

Now, even if a lightning surge enters the high-voltage cutout configured as described above, it will be discharged by the lightning arrester unit 21 via the grounding side electrode 24, the grounding metal fitting 32, and the support metal fitting 31. Protect power distribution equipment such as transformers connected to the load side from lightning surges.

As mentioned above, this high-voltage cutout is such that the lightning arrester unit 21 is mounted and fixed with most of it exposed from the lower back of the main insulator 1, so for example, moisture may infiltrate into the lightning arrester unit 21, or the lightning arrester unit 21 may be exposed to several discharges. When the non-linear resistance element 23 deteriorates due to
1, even if follow-on current interruption becomes impossible and the internal pressure of the lightning arrester unit 21 rises, only the lightning arrester unit is damaged, so the main insulator is not affected and a large-scale public disaster will not occur.

Effects of the invention As detailed above, this invention utilizes the space at the bottom of the back side of the main body insulator to form a lightning arrester unit mounting part, and the lightning arrester unit, which is insulated and molded in the lightning arrester mounting part, can be attached to its large size. The non-linear resistance element may deteriorate due to the part being exposed from the main insulator, or moisture may enter the element, causing creepage of the element, or it may be impossible to block follow-on current when the element is activated. If the internal pressure of the element increases when the lightning occurs, there is a risk of damage to the lightning arrester unit, but as most of the lightning arrester unit is located outside the main insulator, damage to the main insulator is prevented, minimizing public disasters. Not only can it be reduced, but by using the space of a normal box-shaped cut-out of this type, the size can be avoided without changing dimensions in terms of vertical length, etc., compared to conventional types with built-in surge arrester elements. Furthermore, when installing the lightning arrester unit, not only can it be easily installed by simply screwing the lightning arrester unit onto the conductor piece from the outside of the main body insulator, but the fitting groove and fitting protrusion provide sufficient adhesive strength. It is an excellent idea for industrial use because it has excellent effects such as being able to maintain the structure, simplifying the assembly work, and making it strong.

[Brief explanation of the drawing]

The figure is a sectional view of a high-pressure cutout showing an embodiment of this invention. 1... Main body insulator, 3... Power supply side electrode chamber, 4...
Load side electrode chamber, 5...Power supply side fixed electrode, 6...Load side fixed electrode, 9...Lid insulator, 12...Fuse tube, 13...Lightning arrester unit mounting part, 14...Through hole, 18... ...Conductor piece, 21...Lightning arrester unit, 2
3...Nonlinear resistance element, 25...Insulating rod, 20...
... Charging side electrode, 24... Grounding side electrode, 27... Insulating mold, 28... Protective cap, 31... Supporting metal fitting, 32... Grounding metal fitting.

Claims (1)

[Scope of utility model registration request] A pair of power supply side and load side electrode chambers are provided, and a lid insulator with a fuse tube inside is pivotally attached to the main body insulator, which has a fixed electrode and an arc extinguishing chamber inside the same electrode chamber, so that it can be opened and closed. In the cut-out, a lightning arrester unit mounting part consisting of a cylindrical recess and an annular fitting protrusion provided at the inner bottom of the cylindrical recess is formed in the lower part of the back side of the main body insulator, and the lightning arrester unit mounting part is A through hole communicating with the load-side electrode chamber is drilled, and when installing the lightning arrester unit formed with an insulation mold to the mounting portion, a conductor piece extending from the load-side fixed electrode is passed through the through-hole. The charging side electrode of the lightning arrester unit is attached to the conductor piece by screwing from the outside of the main insulator, and the annular fitting groove provided at the base end of the lightning arrester unit is brought into close contact with the fitting protrusion. A grounding fitting that extends from the back of the main body insulator through a through hole provided in the insulation protection cap that covers the ground side electrode of the lightning arrester unit and supports and electrically connects it to expose most of the lightning arrester unit to the outside. 1. A high-voltage cutout with a lightning protection unit, characterized in that the cutout is disposed opposite the end of the lightning protection unit with a predetermined discharge gap.