JPS63294639A - Cutout - Google Patents

Abstract

PURPOSE:To absorb and relieve pressure impact applied by excessively severe thunder purge and coming from lightning arrester units so as to enhance impact resisting property of a main insulator by housing the lightning arrester units inside a cavity provided on the main insulator and leading from the outside to a load side electrode chamber and arranging an impact relieving member between a step part inside the cavity and the lightning arrester units. CONSTITUTION:A cavity 21a leading from the outside to a load side electrode chamber is provided on a main insulator, lightening arrester units 23, 24 are housed in the cavity 21a and also a contractor 37 energized by a compression spring 38 is disposed between a pressure-proof electrode 35 and a step part 21b inside the cavity 21a. Accordingly, if any large gas pressure for separating the pressure-proof electrode 35 from an insulating layer 28 is applied to the pressure-proof electrode 35, this electrode 35 and a conductive plate 34 move to the side of step part 21b within a range for forming a clearance S, namely within a range where an elastic repulse force toward a cylindrical supporting body 33 can be maintained by the energizing force of the compression spring 38. Thereby, any pressure impact can be prevented from being directly applied to the step part 21b, thus the impact resisting property of the man insulator can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION OBJECTS OF THE INVENTION (INDUSTRIAL APPLICATION) The present invention relates to a cutout incorporating a lightning protection unit.

(Conventional technology) As a cutout with a built-in lightning protection unit,
There is one in which a main body insulator is provided with a cavity that communicates with the load-side electrode chamber from the outside, and a lightning arrester unit housed in the cavity is connected to a fixed electrode on the load side by a connecting conductor. However, with this conventional cutout, when the lightning arrester becomes unable to interrupt the follow-on current due to an excessive lightning surge, and high-temperature, high-pressure gas is generated due to the follow-on arc, the gas blows out into the fuse tube, causing damage to the fuse tube. There were problems with the insulators becoming rough, and the main insulators breaking due to uneven heat and pressure shock from the ejected gas, causing them to scatter and fall to the ground.

Therefore, in order to solve the above problems, the applicant has devised a cutout as shown in FIG. The cut-out will be explained using the reference numerals in the embodiments to be described later. In the cavity 21a of the storage cylinder 21 formed at the center of the back side of the main body drawer 1, there is a gap unit 23 having a discharge electrode 27 and a gap unit 23 having a discharge electrode 27. , a non-linear resistor unit 24 having a cylindrical non-linear resistive element 29, and a lightning arrester unit 24 are connected in series and are respectively enclosed in an insulating layer 28, 31. A pressure-resistant electrode 35 made of conductive ceramics and a metal bottom plate 55 are disposed between the step portion 21b formed on the inner circumferential surface of the cavity 21a and the gap unit 23, and both 35.55 are connected to each other. In the joined state, the voltage-resistant electrode 35 is joined to the lower surface of the non-linear resistance body unit 24, and the bottom plate 55 is joined to the step portion 21b via the sheet 56. Further, the voltage-resistant electrode 35 is enclosed in the insulating layer 28, and a string-like base material 39 is filled between the bottom plate 55 and the inner surface of the cavity 21a.

A connecting terminal 57 is provided protruding from the bottom plate 55 and is connected to the stepped portion 2.
It is inserted into the opening of 1b. A conductive plate 58 fixed to the upper end of the connection terminal 57 connects the voltage-resistant electrode 35 and the bottom plate 55.
The lower end of the connection terminal 57 is connected to the load-side fixed electrode by a lead wire 44. Further, a compression spring 52 whose upper and lower ends are connected by a flexible conductor 52a is interposed between the cap fitting 51 attached to the periphery of the upper opening of the storage tube 21 and the non-linear resistor unit 24 via a spring receiver 64. The non-linear resistor unit 24 is grounded via the compression spring 52 and the terminal fitting 53 on the cap fitting 51.

Further, the gap unit 23 includes an outer cylinder 26a,
Two inner cylinders 26b are disposed inside thereof. The discharge electrodes 27 are fixed to the upper and lower end surfaces of both inner cylinders 26b, and a pair of discharge electrodes 27 facing each other between both inner cylinders 26b. A compression spring 59 made of a conductive material is interposed between them.

Further, the non-linear resistor unit 24 includes two non-linear resistive elements 29, and an upper electrode 60. It includes an intermediate electrode 61 and a lower electrode 62. A conductive spacer 63 made of conductive ceramic and having an opening in the center is interposed between both units 23 and 24.

Therefore, with this cutout, when the lightning arrester unit becomes unable to interrupt the follow-on current due to an excessive lightning surge, and high-temperature, high-pressure gas is generated due to the follow-on arc, the gas has a high melting point and is difficult to sustain arc damage. One side is blocked by the electrode 35 and ejected to the other cap metal fitting 51 side, and the cavity 21a is depressurized via the cap metal fitting 51.
This prevents the fuse tube from becoming rough and the main insulator from scattering or falling.

However, in this cutout, the pressure shock of high temperature and high pressure gas generated in the cavity 21a is directly applied to the step portion 21b via the pressure-resistant electrode 35 and the bottom plate 55, so that the step portion 21b may be missing or the main body may be damaged. There was a risk that cracks would occur throughout the insulator 1.

This invention was made in consideration of the above circumstances,
Its purpose is to provide a cutout that can absorb and alleviate the pressure impact from the lightning arrester unit that is applied to the main insulator 1 when it becomes unable to interrupt the follow-on current due to an excessive lightning surge, thereby improving its impact resistance. It's about doing.

Structure of the Invention (Means for Solving the Problems) In order to achieve the above object, the present invention provides a cavity communicating with the load-side electrode chamber from the outside in the main insulator, and a lightning protection is provided in the cavity. A shock absorbing member is disposed between the lightning arrester unit and a stepped portion formed inside the cavity, and the shock absorbing member is connected to a cylindrical support supported by the stepped portion. , a conductive plate disposed between the lightning arrester unit and the cylindrical support, a conductive rod penetrating the step and into the cylindrical support, and a conductive rod inserted through the conductive plate. A contact element is placed in close contact with the lightning arrester unit and is biased by a compression spring that makes the connection between the conductive plate and the cylindrical support body spring. The system uses a configuration in which it is connected to.

(Function) Therefore, when the lightning arrester unit becomes unable to interrupt the follow-on current due to an excessive lightning surge and high-temperature, high-pressure gas is generated in the cavity due to the follow-on arc, one side of the gas is shielded by the shock absorbing member, and the shock The pressure impact applied to the conductive plate of the relaxation member is absorbed or alleviated by the biasing force of the spring within the range of maintaining the elastic force between it and the cylindrical support, thereby preventing the pressure impact from being applied directly to the stepped portion. The insulator itself is protected.

(Example) Hereinafter, an example embodying the present invention will be described in detail with reference to the drawings.

A power source side electrode chamber 3 and a load side electrode chamber 4 are formed within the main body insulator 1 made of porcelain, which are partitioned by a partition wall 2.2. A fixed electrode 5.6 and an arc extinguishing chamber 7.8 are embedded and fixed in the electrode chambers 3 and 4 at their base end portions with a filler 9, respectively. Connecting terminals 10.11 are attached to the fixed electrodes 5.6, respectively, and are respectively connected to a power supply side lead wire and a load side lead wire (not shown).

An insulating cover 12 is pivotally attached to the open side (lower side in FIG. 1) of the main body holder 1 so as to be openable and closable, and a pair of fixed electrodes 5.6 are provided inside the insulating cover 12 to connect or open the fixed electrodes 5.6. A fuse tube 13 equipped with contact blades 13a and 13b is removably attached.

A housing cylinder 21 is integrally formed in the center of the back side (upper side in FIG. 1) of the main insulator 1, and a cavity 21 is formed inside the housing cylinder 21.
a is formed. The cavity 21a is open at the upper part and opened at the lower part to the open side,
It communicates with the load-side electrode chamber 4 via a guide hole 2a provided in the partition wall 2. Further, a stepped portion 21b having an opening having an inner diameter smaller than the upper opening is formed on the inner circumferential surface of the cavity 21a.

Inside the cavity 21a is a lower conductive unit 22 constituting a shock absorbing member. A gap unit 23°, a nonlinear resistor unit 24, and an upper conductive unit 25 are housed in this order.

Here, the gap unit 23 and the nonlinear resistor unit 24 will be explained. As shown in FIG. 2, the gap unit 23 includes an outer cylinder 26a made of an inorganic material such as porcelain, and the inside thereof is made of quartz glass having heat resistance and impact resistance.

An inner cylinder 26b made of an inorganic material such as alumina porcelain or sound-absorbing porous ceramics is provided. Discharge electrodes 27 are fixed to both upper and lower end surfaces of the outer cylinder 26a or the inner cylinder 26b, respectively. Further, an insulating layer 28 is provided between the outer circumferential surface of the gap unit 23 and the inner circumferential surface of the cavity 21a, which is formed by filling an inorganic material such as low-melting point glass and heating and melting it together with the main body insulator 1 in a furnace. It is being This insulation Ji 128 is welded and formed between both 23 and 21a without a gap, and insulates and encapsulates the gap unit 23.

The non-linear resistor unit 24 includes a non-linear resistor element 29 which is made of sintered material mainly made of zinc oxide (ZnO) and is formed into a cylindrical shape having an inner cavity 29a.
Lead plate type current collecting electrodes 30 are connected to the upper and lower surfaces of the electrodes 9 and between them. The non-linear resistor unit 24 is connected to the gap unit 23 via the lower current collecting electrode 30.
are connected in series. Said non-linear resistor unit 2
An insulating layer 31 is formed by filling an insulating material with high elasticity such as closed foam rubber between the outer circumferential surface of the cavity 21a and the inner circumferential surface of the cavity 21a. 24 is insulated.

The lower conductive unit 22 is disposed between the gap unit 23 and the stepped portion 21b of the storage tube 21. The lower conductive unit 22 is made of a conductive material such as copper or brass, and includes a spring receiver 32 joined to the step portion 21b, with a conductive hole 32a formed in the center thereof. A cylindrical support 33 made of a conductive material is bonded onto the spring receiver 32, and a conductive plate 34 is disposed on the cylindrical support 33 to cover its upper opening. A voltage-resistant electrode 35 made of conductive ceramics such as zirconium boride is bonded between the conductive plate 34 and the gap unit 23 and can electrically connect both the plates 34 and 23.

The conductive rod 36 is inserted through the opening of the stepped portion 21b, and a cylindrical contact 37 made of a conductive material is soldered to the upper end of the conductive rod 36, with the cylindrical contact 37 fitted in the central opening. A compression spring 38 made of a conductive material is interposed between the contactor 37 and the conductive plate 34, and the spring force causes the conductive plate 3 to
4 is pressed against the voltage-resistant electrode 35 to establish electrical continuity between the two, and the conductive plate 34 and the cylindrical support 33
A gap S is formed between them.

A string-like base material 39 made of glass wool is wound around the outer periphery of the lower conductive unit 22, and glass beads 40 are filled between the conductive unit 22 and the inner surface of the cavity 21a. There is. The base material 39 has an insulating layer 2 between the outer periphery of the gap unit 23 and the cavity 21a.
This prevents the inorganic insulating material filled to form the lower conductive unit 8 from entering the inside and outside of the lower conductive unit 22. An O-ring 41 is interposed between the opening of the stepped portion 21b and the conductive rod 36. The lower part of the cavity 21a is filled with an insulator 42, and a silicon sealant 43 filled between the insulator 42 and the O-ring 41 closes the opening of the stepped portion 21b. A lead wire 44 for connecting the conductive unit 22 to the load-side fixed electrode 6 is attached to the lower end of the conductive rod 36 of the lower conductive unit 22.

Next, the upper conductive unit 25 will be described. The unit 25 is disposed above the non-linear resistor unit 24 in the cavity 21a, and includes a pair of inner and outer conductive spacers 45 and 46 in the shape of a cylinder. . The leg plate 45a of the outer conductive spacer 45 is connected to the collector electrode 30 of the non-linear resistor unit 24, and an opening 45b is formed in the center thereof, and a shelf plate 46a is formed on the upper part of the inner conductive spacer 46. and the leg plate 4 of the outer conductive spacer 45
A desiccant 47 is housed in the space between the cylindrical member 5a and the cylindrical member 5a.

On the shelf board 46a of the inner conductive spacer 46 is a bowl-shaped spring receiver 4 made of a conductive material and having an opening 48a at the bottom.
8 is joined, and the opening 48a is made of lead.

It is closed with a lid 49 made of copper or the like. A compression spring 52 whose upper and lower ends are connected by a flexible conductor 52a is interposed between the cap metal fitting 51 which is caulked to the upper end of the storage tube 21 via a cushion material 5o and the spring receiver 48. , the spring 52 is locked to a hook 51a protruding from the inner surface of the cap metal fitting 51.

It is preferable that the cap fitting 51 is provided with a notch or the like so that it can be partially melted or ruptured by high-temperature, high-pressure gas such as a follow-on arc generated within the cavity 21a to release gas.

The upper conductive unit 25 is connected to the non-linear resistor unit 2.
4 is enclosed by the insulation 1i31, and a silicon sealant 43 is filled between the outer periphery of the upper end of the upper conductive unit 25 and the inner surface of the cavity 21a, and is attached to the main insulator 1.

Furthermore, a terminal fitting 53 for connecting a grounding line is provided on the upper surface of the camping fitting 51.

In the cutout configured as described above, when a lightning surge enters the lightning protection unit placed between the load side fixed electrode 6 and the grounding wire terminal fitting 53, nonlinearity in the nonlinear resistor unit 24 occurs. Lightning surges are discharged to the ground through the resistor element 29 and the gap unit 23, suppressing voltage rise and preventing line failures due to cutouts, flash shorts in transformers, etc.

In this embodiment, each unit 22, 23, 24
．． 25 is sealed in the cavity 21a via the insulating layer 28.31, moisture absorption is prevented, and fluctuations in discharge voltage characteristics in the gap unit 23 and non-linear resistor unit 24 are prevented.
It is possible to prevent deterioration due to creepage leakage current, and improve the reliability and durability of the lightning arrester unit.

In addition, if the lightning arrester unit becomes unable to interrupt the follow-on current due to excessive lightning surge, etc., and a follow-on arc is generated, the air in the inner cavity 29a of the non-linear resistor unit 24 is heated and expanded, resulting in high temperature and high pressure. In this embodiment, the nonlinear resistor unit 2
4, that is, on the side of the fuse tube 13, a voltage-resistant electrode 35 made of conductive ceramics that has a high melting point and is not easily damaged by arcs is disposed, so that gas is not blown out downward from the voltage-resistant electrode 35. Therefore, the insulating lid 12 and the fuse tube 13 are protected and roughness is prevented. The high-temperature, high-pressure gas that is prevented from ejecting downward by the pressure-resistant electrode 35 melts the lid 49 on the spring receiver 48 facing the inner cavity 29a, and
The cap metal fitting 51 is bulged and deformed to eject from the gap between the cushioning materials 50, or the cap metal fitting 51 is partially melted and ruptured to eject and reduce uneven heat and pressure impact on the main body insulator 1, and then cut out. This prevents the objects from scattering and falling.

Note that the upper conductive unit 25 is connected to the openings 45b and 4.
Gas is released from 8a, but at this time, damage to the main insulator 1 is reduced by shielding heat and pressure impact to the opening of the main insulator 1.

Furthermore, in this embodiment, since the contactor 37 biased by the compression spring 38 is disposed between the voltage-resistant electrode 35 and the step portion 21b in the cavity 21a, the voltage-resistant electrode 35 can be easily peeled off from the insulating layer 28. When a large gas pressure is applied to the voltage-resistant electrode 35, the voltage-resistant electrode 35 and the conductive plate 34 are in the range where the gap S is formed, that is, the elastic force between the pressure-resistant electrode 35 and the cylindrical support body 33 is maintained by the biasing force of the compression spring 38. It moves toward the stepped portion 21b within the possible range, thereby preventing pressure shock from being directly applied to the stepped portion 21b, thereby increasing the impact resistance of the main body insulator 1.

Furthermore, since the desiccant 47 is stored in the upper conductive unit 25 provided above the non-linear resistor unit 24, even if moisture is absorbed into the upper conductive unit 25, the desiccant 47
This can contribute to suppressing the deterioration factors of the nonlinear resistance element 29.

In addition, in this embodiment, the gap unit 23 is placed closer to the voltage-resistant electrode 35 than the non-linear resistor unit 24, so that the high temperature, high pressure gas generated within the gap unit 23 is instantaneously directed in one direction. By doing so, the pressure can be accelerated and released effectively.

In this embodiment, when the lower conductive unit 22 and the gap unit 23 are installed in the cavity 21a, the spring receiver 32, the cylindrical support 33, and the compression spring 38 are sequentially housed in the cavity 21a, Next, the conductive rod 36 and the contact 37 that have been integrated in advance are inserted into the cavity 21a, and the conductive rod 36 is inserted into the guide hole 32a of the spring receiver 32 and the step. 21b, and the contact 37 is engaged with the upper end of the compression spring 38. In this state, the contact 37 is held in a position protruding upward from the upper end of the cylindrical support 33 by the spring force of the compression spring 38.

Next, the conductive plate 34 and the voltage-resistant electrode 35 are superimposed on the contactor 37, and a string-like base material 39 and a glass bead are placed between the voltage-resistant electrode 35 and the outer periphery of the cylindrical support 33 and the inner surface of the cavity 21a. Fill 40. After disposing the gap unit 23 on the voltage-resistant electrode 35, the conductive rod 36 is pulled downward against the spring force of the compression spring 38, and the contact 37 is pulled downward against the spring force of the compression spring 38.
- Insulating N between the gap unit 23 and the cavity 21a with the conductor 1i34 and the opposing end of the cylindrical support 33 in contact with each other while being separated from the conductive plate 34.
Fill with 28 inorganic materials. At this time, even if the material melts as will be described later, it is blocked by the string-like base material 39, so that it will not invade the inside or outside of the lower conductive unit 22.

When the inorganic material is heated and melted in the above state, an insulating layer 2 is formed between the gap unit 23 and the cavity 21a.
8 is formed, the gap unit 23 is fixed, and the cylindrical support 33 and the conductive plate 34 are
A gap S is formed between them. Note that a glass cloth with a high melting point or the like is interposed in advance between the opposing ends of the cylindrical support 33 and the conductive plate 34 to enlarge this gap S, expand the elastic force maintenance range, and absorb pressure shock. It can also enhance the effect.

Effects of the Invention As detailed above, the present invention provides a main body insulator with a cavity that communicates with the load-side electrode chamber from the outside, houses a lightning arrester unit in the cavity, and has a lightning protection unit formed inside the cavity. Since a shock-reducing member is placed between the stepped section and the lightning arrester unit, it can be used to reduce the impact when the lightning arrester unit becomes unable to cut off the follow-on current due to excessive lightning surge and high-temperature, high-pressure gas is generated due to the follow-on arc. The member prevents high-temperature, high-pressure gas from blowing out toward the fuse part, and also absorbs and alleviates the pressure impact applied to the stepped part in the cavity, improving the impact resistance of the insulator body. It is possible to prevent the insulator from blowing out toward the fuse portion and causing the fuse tube to become rough and the main insulator from scattering and falling.

In addition, since the pressure shock transmitting member is elastically supported by the spring, the impact mitigation ability can be significantly improved compared to a cushion run sheet or the like.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a cutout embodying the present invention, FIG. 2 is an enlarged sectional view of a main part, and FIG. 3 is a view corresponding to FIG. 2 of a conventional cutout. In the figure, 1... main body insulator, 3... power supply side electrode chamber, 4...
...Load side electrode chamber, 5.6...Fixed electrode, 13...
Fuse tube, 22... Lower conductive unit as a shock absorbing member, 23... Gap unit, 24... Non-linear resistor unit (a lightning arrester unit is constituted by the above 23.24), 33. ...Tubular support, 34
...Conductive plate, 36... Conductive rod, 38... Compression spring, S... Gap. Patent applicant Chubu Electric Power Co., Ltd. Nippon Insulators Co., Ltd. Takamatsu Electric Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. A main body insulator (1) made of porcelain, which is provided with fixed electrodes (5, 6) in electrode chambers (3, 4) on the power supply side and the load side, respectively;
In the cutout having a fuse tube (13) that connects or opens the two fixed electrodes (5, 6), a cavity (21a) is provided in the main body insulator (1) that communicates with the load side electrode chamber (4) from the outside. ), and the lightning arrester unit (23, 24) is accommodated in the cavity (21a), and a stepped portion (21b) formed inside the cavity (21a) and the lightning arrester unit (23, 24) are provided. There is a shock absorbing member (2
2), and the shock absorbing member (22) is placed in the step portion (
21b), a conductive plate (34) disposed between the lightning arrester unit (23, 24) and the cylindrical support (33), and the stepped portion (21b). ) and into the cylindrical support (33).
6), the conductive rod (36) is brought into close contact with the lightning arrester unit (23, 24) via the conductive plate (34), and the distance between the conductive plate (34) and the cylindrical support (33) is The lightning arrester unit (23, 24) is connected to the fixed electrode (6) on the load side via the conductive rod (36). A cutout featuring the following.