JPH0516848Y2 - - Google Patents

Description

[Detailed description of the invention] Purpose of the invention (industrial application field) This invention relates to a cylindrical cutout that protects transformers and prevents accidents on power lines, and in particular relates to a cylindrical cutout with a built-in lightning arrester unit. .

(Prior Art) Conventionally, a cavity is provided in a cylindrical cut-out body insulator, and the outer opening of the cavity is sealed.
It is known that a non-linear resistance element and a discharge gap part are housed in the cavity. (For example, Jikko Sho 60-
(Refer to No. 10261 and Utility Model Publication No. 61-15565) (Problem that the invention attempts to solve) However, with the conventional cylindrical cut-out, the linear resistance element of the lightning arrester unit is damaged due to excessive lightning surge, for example. If it becomes impossible to block the follow-on flow and a follow-on flow occurs, and high-temperature, high-pressure gas is generated in the cavity of the main insulator due to the follow-on flow, the main insulator is destroyed by the uneven heat and pressure shock, falling to the ground and scattering. This posed a public safety problem.

The object of this invention is to provide a cylindrical cutout that eliminates the above-mentioned problems.

Structure of the Device (Means for Solving the Problems) In order to solve the problems described above, this device has a cylindrical cut-out that defines the lower end of the main insulator with the inner cavity of the main insulator and penetrates the lower end of the main insulator. A storage cylinder having an inner cavity communicating through a hole is integrally formed, a pressure-resistant electrode is accommodated and fixed on the inner top surface of the inner cavity so as to be able to shield the through-hole, and the voltage-resistant electrode and the lower electrode are connected. death,
In the lumen, a cap unit having a pair of discharge electrodes and hermetically sealing a discharge space, and a cap unit disposed in contact with the front voltage-resistant electrode, and a non-linear resistor unit in contact with this unit are connected in series. further, a conductive tube is provided on the entire surface of the non-linear resistor unit at the outer opening edge of the storage tube;
A method is adopted in which a cap member that can release pressure is fitted and fixed opposite to this conductive cylinder.

(Function) In this invention, a pressure-resistant electrode is placed and shielded at the communication point with the fuse tube at the inner top of the housing tube formed integrally with the main body insulator, and the inner cavity of the housing tube is placed in front of the non-linear resistor unit. Since the gap unit and the non-linear resistor unit are connected in series, the follow-on current of the non-linear resistor unit is prevented by an excessive lightning surge. When the breaking ability decreases and high-temperature, high-pressure gas is generated in the inner cavity due to a follow-on arc, this high-temperature, high-pressure gas is transferred to the lower electrode side by the pressure-resistant electrode at the boundary between the insulator body and the housing cylinder. is prevented from moving and ejects from the inside of the housing cylinder toward the cap member, and is guided by the conductive cylinder in front of the nonlinear resistor unit, which opens the cap member and releases the pressure. Damage to the main insulator provided with the storage cylinder is prevented.

(Embodiment) Hereinafter, an embodiment embodying this invention will be described in detail with reference to the drawings.

An upper electrode 2 is provided on the upper side of the inner cavity 1a of the main insulator 1, which is made of porcelain and has a cylindrical shape, and a lower electrode 3 is provided on the lower side. A fuse tube 4 is attached so as to be removable downward. An upper lead wire 5 on the power supply side is connected to the upper electrode 2, and a lower lead wire 6 on the load side is connected to the lower electrode 3 and led out from the side of the main body insulator 1.

A cylindrical hook member 7 is fitted into the lower end opening of the main body insulator 1, and a seal plug 8 is removably attached to the lower end opening of the hook member 7 with an elastic stopper (not shown). It is connected to the hook member 7 by a string 9.

A storage tube 10 is integrally formed in the lower end side wall of the main insulator 1 in the vertical direction, and its inner cavity 10a is separated from the inner cavity 1a of the main insulator and opens to the outside at the lower part. The boundary portion is communicated with the inner cavity 1a through the hole 1b.

An attachment band 11 for attaching the cutout to an armrest (not shown) is fitted onto the outer peripheral surface of the main body insulator 1, and is tightened and fixed with a bolt 12.

A pressure-resistant electrode 13 made of conductive ceramic such as zirconium boride is provided on the inner top surface 1c of the inner cavity 10a.
is arranged to seal and shield the through hole 1b between the inner cavity 1a of the main body insulator 1 and the inner cavity 10a of the housing cylinder 10, and the voltage resistant electrode 13 and the lower electrode 3 are electrically connected by a connecting conductor 14. ing. A gap unit 15, a nonlinear resistor unit 19, and a conductive unit 25 are housed in series in series on the underside of the voltage-resistant electrode 13.

Note that the voltage-resistant electrode 13 is made of Fe-Ni with a thickness that does not easily break or melt away due to high temperature and high pressure gas.
An alloy or the like may also be used.

Here, the gap unit 15 and the nonlinear resistor unit 19 will be explained.

The gap unit 15 includes an insulating cylinder 16 made of a heat-resistant inorganic material such as alumina porcelain.
and a pair of discharge electrodes 17, 17 fixed to both upper and lower end surfaces of the insulating cylinder 16 by silver soldering or the like to form a discharge gap G. or,
An insulating layer 1 formed by heating and welding an insulating material such as low melting point glass between the outer circumferential surfaces of the voltage-resistant electrode 13 and the gap unit 15 and the inner circumferential surface of the inner cavity 10a.
8 is provided, and fixes the voltage-resistant electrode 13 and gap unit 15 to the inner cavity 10a. The discharge electrode 17 is made of a thin metal plate such as a low melting point alloy, and
Notches and the like are provided as appropriate to enable melting and fracture by hot gas such as follow-on arc.

The nonlinear resistor unit 19 is made of a sintered material mainly made of zinc oxide (ZnO) and has a through hole 20a.
The non-linear resistance elements 20 are provided with a predetermined number of non-linear resistance elements 20 each having a thickness of 100 μm and a thickness of 100 μm. Electrode plates 21 made of soft metal such as lead are disposed on the upper and lower surfaces of the non-linear resistance elements 20 or between the non-linear resistance elements 20, and the non-linear resistance elements 20 are joined to each other.
The non-linear resistor unit 19 is connected in series to the gap unit 15 via the upper electrode plate 21. The outer periphery of the non-linear resistor unit 19 is made of a heat-shrinkable tube 2 made mainly of EPR (ethylene propylene rubber) or polyethylene.
2 and is insulated and enclosed in a silicone rubber tube having excellent heat resistance.

A cap fitting 24 as a cap member is caulked to the lower end of the storage tube 10 via a sealing material 23 to close the lower opening of the inner cavity 10a. A conductive unit 25 is interposed between the cap metal fitting 24 and the front surface of the non-linear resistor unit 19. This conductive unit 25
A conductive cylinder 26 disposed on the lower front surface of the non-linear resistor unit 19 in 0a, and a coil-shaped compression interposed between the upper surface 26a of the conductive cylinder 26 and the breakable cap fitting 24. spring 27
and a flexible conductor 28 for energization attached to the compression spring 27.

The cap metal fitting 24 has a thin metal plate such as a copper plate with a cap-shaped central surface protruding from its central surface so that the cap fitting 24 can bulge and deform due to the internal gas pressure caused by the short-circuit current arc when the follow-on current cannot be interrupted. It is formed with a notch (not shown) for breaking the hole, etc.

The non-linear resistor unit 19 and the conductive tube 26
An insulating layer 29 made of silicone rubber, urethane rubber, RTV silicone rubber, or the like is adhesively formed between the outer peripheral surface of the lumen 10a and the inner peripheral surface of the inner cavity 10a. A terminal fitting 30 for connecting a ground wire is provided on the upper surface of the cap fitting 24, and is connected to the mounting band 11 by a lead wire 31.

Next, the operation of the cylindrical cutout configured as described above will be explained.

When a lightning surge enters the fuse tube 4 disposed in the inner cavity 1a of the main body insulator 1, the lightning surge is discharged to the ground through the nonlinear resistance element 20 of the nonlinear resistance unit 19 and the gap unit 15, causing a voltage increase. Since the current is suppressed and the follow-on current is instantaneously cut off, line failures due to cylindrical cutouts, flash shorts in transformers, etc. are prevented.

In this embodiment, the nonlinear resistor unit 19 is covered with a heat-shrinkable tube 22 and an insulating layer 29, and the gap unit 15 and the conductive unit 25 are sealed in the inner cavity 10a via the insulating layers 18 and 29. Furthermore, a cap fitting 2 is attached to the lower end of the inner cavity 10a.
4 is attached, there is no intrusion of wind and rain, and deterioration of the non-linear resistance element 20 due to moisture absorption and fluctuation of the discharge voltage characteristics of the gap unit 15 can be prevented. Even if the non-linear resistance element 20 becomes unable to interrupt the follow-on current due to an excessive lightning surge and the high-temperature, high-pressure gas of the follow-on arc is generated, the main body insulator 1 absorbs or alleviates the impact and shields the high heat. can prevent the impact on

Furthermore, in this embodiment, the nonlinear resistor unit 19
A voltage-resistant electrode 13 made of conductive ceramics with a high melting point is arranged on the upper side, and a gap unit 15 and a non-linear resistor unit 19 having a through hole 20a, which can be opened by melting both discharge electrodes 17, are arranged. Therefore, even if the non-linear resistor unit 19 becomes unable to interrupt the following flow and an arc occurs in the gap unit 15 as described above, the high-temperature, high-pressure gas will interrupt the arc from the voltage-resistant electrode 13. Since it is not ejected into the inner cavity 1a of the main insulator 1, the insulator main body 1, the storage tube 10, and the fuse tube 4 are protected and prevented from falling off. The high-temperature, high-pressure gas, which is prevented from being ejected upward by the pressure-resistant electrode 13, heats and expands the air in the lumen 10a, is pressure accelerated, and reaches the front surface of the non-linear resistor unit 19 in the lumen 10a. The cap metal fitting 24 is guided by the conductive cylinder 26 facing the conductive cylinder 26 and ejects through the conductive cylinder 26 through bulging deformation or partially melting and rupturing, thereby alleviating the uneven heat and pressure impact of the main body insulator 1. It can prevent scattering and falling due to damage.

The peripheral wall of the conductive cylinder 26 of the conductive unit 25 shields the ejected gas from the peripheral wall of the inner cavity 10a, prevents uneven heat and pressure impact on the housing cylinder 10, and reduces damage to the main body insulator 1.

Further, in the above embodiment, the nonlinear resistor unit 19
Since the outer peripheral surface of the non-linear resistance element 20 is covered with a heat-shrinkable tube 22 and a flexible or elastic insulating layer 29 is provided between the tube 22 and the inner cavity 10a, expansion due to discharge heat of the non-linear resistance element 20 is prevented. In addition, stress on the housing cylinder 10 can be prevented, and even if the non-linear resistance element 20 is crushed by the following flow, the pressure impact on the main insulator 1 is alleviated, thereby providing an explosion-proof effect.

Note that the present invention can also be embodied as follows.

As shown in FIG. 3, a housing cylinder 10 is integrally formed so as to protrude horizontally from the lower side surface of the main body insulator 1, and a pressure-resistant electrode 13 is provided in the inner cavity 10a of the housing cylinder 10.
Gap unit 15, nonlinear resistance unit 1
9, conductive unit 25, etc., and fit the cap fitting 24.

Effects of the invention As detailed above, this invention forms a storage cylinder in the insulator body, places a pressure-resistant electrode on the top of the inside to shield the arc, and uses a conductive cylinder to guide the arc through the inner cavity of the storage cylinder. Since it is sealed with the opposed cap member that can release the pressure, the following current blocking ability of the non-linear resistor unit is reduced, and when high temperature and high pressure gas is generated in the internal cavity of the gap unit due to the following current arc, this high temperature,
The high-pressure gas is prevented from moving toward the lower electrode of the cutout by the pressure-resistant electrode, and the boundary between the insulator body and the storage cylinder is protected, and the gas ruptures the cap member and is released from the storage cylinder. As a result, by protecting the insulator body and the fuse tube and preventing damage, it is possible to prevent the main insulator body from scattering or falling. In addition, in this design, the gap unit and the non-linear resistor unit are enclosed in the lumen of the storage cylinder, which is separated from the lumen of the main insulator, so wind and rain do not enter into these parts, preventing deterioration of the non-linear element due to moisture absorption. This has the effect of preventing fluctuations in discharge voltage characteristics of the gap unit.

[Brief explanation of the drawing]

Figure 1 is a vertical sectional view of the center of only the essential parts of a cylindrical cutout embodying this invention, Figure 2 is a front view showing the entire cylindrical cutout, and Figure 3 is a sectional view showing another example of the invention. It is. 1...Body insulator, 1a, 10a...Inner cavity, 1b
...Through hole, 2...Top electrode, 3...Bottom electrode,
4...Fuse pipe, 5...Upper lead wire, 6...
Lower lead wire, 10... Storage tube, 10b... Step part, 13... Voltage resistant electrode, 15... Gap unit, 18, 29... Insulating layer, 19... Non-linear resistor unit, 20... Non-linear resistance Motoko, 24...
A cap metal fitting as a cap member, 25... conductive unit, 26... conductive cylinder, 27... compression spring, 28... flexible conductor, 29... insulating layer.

Claims (1)

[Claim for Utility Model Registration] An upper electrode 2 and a lower electrode 3 are arranged in the inner cavity 1a of a cylindrical porcelain main body insulator 1, and both electrodes 2 and 3 are connected or opened. In a cylindrical cut-out in which a fuse tube 4 is removably attached to the lower end opening of the main insulator 1, an inner lumen is defined from the inner lumen 1a of the main insulator 1 and communicated with the lower end of the main insulator 1 through a through hole 1b. 10a is integrally formed, and a voltage-resistant electrode 13 is housed and fixed in the inner top surface 1c of the inner cavity 10a so as to be able to shield the through-hole 1b, and the voltage-resistant electrode 13 and the lower electrode 3 connect,
A pair of discharge electrodes 17, 17 are provided in the inner cavity 10a.
The discharge space G is hermetically sealed, and a gap unit 15 disposed in contact with the front voltage-resistant electrode 13 and a non-linear resistor unit 19 in contact with this unit are stacked and housed in series, moreover,
A conductive tube 26 is provided on the entire surface of the non-linear resistor unit 19 at the outer opening edge of the housing tube 10, and a cap member 24 that is capable of releasing pressure faces the conductive tube.
A cylindrical cutout characterized by being fitted and fixed.