JPH097805A - Lightning arrester - Google Patents

Abstract

PURPOSE: To reduce the explosion power of a lightning arrester for suppressing the scattering or broken pieces of voltage non-linear resistor or electrode, etc. CONSTITUTION: A cylindrical body 6 with one end fixed to a voltage non-linear resistor 5 and the other end having a cover 6c is provided while an electrode 8 protruded from the cover 6c is contained inside the cylindrical body 6 making movable therein. On the other hand, the periphery of the resistor 5 and a part of both cylindrical bodies 6, 6 are encircled with a mold insulator 11 so as to move the electrode 8 in case of an inner explosion, thus providing pressure relieving means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightning arrester for protecting peripheral equipment or a person from an explosion accident caused by overvoltage such as lightning surge or switching surge, or insulation breakdown due to deterioration over time in a distribution line or distribution equipment. Is.

[0002]

2. Description of the Related Art FIG.
Sectional drawing which shows the structure of the conventional lightning arrester shown by the 4th publication.
FIG. 16 is a plan view of FIG. In FIGS. 15 and 16, reference numeral 1 denotes a cylindrical voltage nonlinear resistor (hereinafter simply referred to as a resistor) made of a sintered body containing zinc oxide as a main component. Reference numeral 2a is an electrode portion soldered to both end surfaces of the resistor 1, 2b is a round bar-shaped external terminal portion that is provided concentrically with the electrode portion 2a, and the electrode portion 2a and the external terminal portion 2b form the electrode 2
Is composed. 3 is a part of the external terminal portion 2b,
It is a mold insulator made of epoxy resin that surrounds a part of the resistor 1 and the electrode 2. It should be noted that the resistor 1, the electrode 2 and the mold insulator 3 constitute a lightning arrester 4.

Next, the operation will be described. When an overvoltage such as a lightning surge or a switching surge is applied to the electrode 2, a large current flows through the resistor 1. When the lightning arrester 4 exceeds the discharge withstand capability, the resistor 1 is broken and an arc discharge is generated inside or inside the resistor 1. For this reason, the resistor 1 instantly becomes high in temperature, undergoes rapid thermal expansion and becomes high pressure, and the lightning arrester 4 explodes. Then, the fragment of the resistor 1, the electrode 2 or the mold insulator 3 destroyed by this explosion
Could be destroyed and scattered, damaging peripheral equipment or people.

In addition, even if the surge arrester 4 is applied with an overvoltage such as a lightning surge or a switching surge that is less than the discharge withstand voltage, the surge arrester 4 is repeatedly exposed to the overvoltage and causes a dielectric breakdown, or due to deterioration over time, the electrode 2 and the mold insulator. There was a case in which a gap was formed between No. 3 and 3, and when rainwater penetrated into this gap and a dielectric breakdown occurred, an explosion occurred.

[0005]

In the conventional lightning arrester 4 as described above, a high pressure is generated in the resistor 1 due to the dielectric breakdown due to the overvoltage, and the resistor 1 explodes. There is a defect that the electrode 2 or the mold insulator 3 is broken and scattered to damage peripheral devices or people. In addition, there is a problem that a gap is created between the electrode 2 and the mold insulator 3 due to deterioration over time, and rainwater enters the gap to cause dielectric breakdown.

The present invention has been made to solve the above problems, and a first object thereof is to release high pressure generated in a resistor by dielectric breakdown and reduce the power of explosion. You get a lightning arrester.

A second object is to obtain a lightning arrester capable of suppressing the scattering of fragments or electrodes of a resistor destroyed by an explosion.

A third object is to obtain a lightning arrester capable of preventing rainwater from entering between the electrode and the mold insulator.

[0009]

In a lightning arrester according to the present invention, a tubular body is fixed to a resistor, and a first electrode electrically connected to one end of the resistor is moved inside the tubular body. The second electrode is electrically connected to the other end of the resistor, and when the pressure is applied between the resistor and the first electrode, the first electrode moves inside the tubular body. It is provided with a release means for releasing pressure.

Further, a stopper is provided to prevent the first electrode from separating from the cylindrical body when pressure is applied between the resistor and both electrodes.

Further, a tubular body having one end fixed to the resistor and a cover at the other end is provided, and an electrode portion electrically connected to one end of the resistor is provided. The first electrode having an external terminal portion projecting from the cover is housed so as to be movable inside the tubular body, and the second electrode is electrically connected to the other end of the resistor to connect the resistor and the first electrode. When a pressure is applied between the first electrode and the first electrode, the first electrode moves inside the tubular body so that the first electrode is ruptured to release the pressure, and the first electrode is separated from the tubular body. A stopper for preventing the above is provided on the cylindrical body, and the resistor and the cylindrical body are surrounded by the mold insulator.

Further, the rupture portion is provided with a cutout portion.

Further, a thin portion is provided at the rupture portion.

Further, a tubular body having one end fixed to the resistor and a cover at the other end is provided, and an electrode portion electrically connected to one end of the resistor is provided, and the tubular body is provided so as to project from the electrode portion. The first electrode having an external terminal portion projecting from the cover is housed so as to be movable inside the tubular body, and the second electrode is electrically connected to the other end of the resistor to connect the resistor and the first electrode. When the pressure is applied between the first electrode, the discharge path is formed by moving the first electrode inside the cylindrical body to provide the discharge means for discharging the pressure,
A stopper for preventing the first electrode from coming off the tubular body is provided on the tubular body, and the resistor and the tubular body are surrounded by a mold insulator.

Further, as a discharging means, a pressure releasing port is provided in the cylindrical body.

Further, a pressure release port is provided in the electrode as a release means.

Further, a sealing member is provided between the first electrode and the cylindrical body.

Furthermore, the tubular body is fixed to the resistor, the first electrode electrically connected to one end of the resistor is housed so as to be movable inside the tubular body, and the other end of the resistor is attached. The second electrode is electrically connected, and when the pressure is applied between the resistor and the first electrode, the first electrode moves inside the cylindrical body to release the pressure. A stopper is provided so as to surround the tubular body so as to prevent the water from scattering.

[0019]

In the lightning arrester configured as described above, the tubular body is fixed to the resistor, and the first electrode electrically connected to one end of the resistor is housed so as to be movable inside the tubular body. Therefore, when pressure is applied between the resistor and the first electrode, the first electrode moves inside the tubular body to release the pressure.

Further, when pressure is applied between the resistor and both electrodes, the first electrode moves inside the tubular body to release the pressure, and the first electrode collides with the stopper. The separation of one electrode from the cylindrical body is suppressed.

Further, when pressure is applied between the resistor and the first electrode, the first electrode moves inside the tubular body and collides with the ruptured portion of the tubular body, so that the ruptured portion is ruptured. The pressure is released and the detachment of the first electrode from the tubular body is suppressed.

Further, since the notch is provided at the rupture portion,
When the first electrode moves inside the tubular body and collides with the ruptured portion of the tubular body, the ruptured portion is easily ruptured and the pressure is released quickly.

Further, since the ruptured portion is provided with a thin portion,
When the first electrode moves inside the tubular body and collides with the ruptured portion of the tubular body, the ruptured portion is easily ruptured and the pressure is released quickly.

Also, when pressure is applied between the resistor and the first electrode, the first electrode moves inside the cylindrical body to form the discharge path, so that the pressure is discharged. Then, since the moved first electrode collides with the stopper, the first electrode is prevented from being separated from the tubular body.

Further, since the pressure releasing port is provided in the tubular body as the releasing means, the first electrode moves inside the tubular body when pressure is applied between the resistor and the first electrode. The pressure release port of the cylindrical body is opened to release the pressure.

Further, since the pressure releasing port is provided in the first electrode as the releasing means, when the pressure is applied between the resistor and the first electrode, the first electrode moves inside the cylindrical body. The pressure release port of the first electrode is opened to release the pressure.

Further, since the sealing member is provided between the first electrode and the cylindrical body, intrusion of rainwater is prevented.

Furthermore, since the first electrode electrically connected to one end of the resistor is housed so as to be movable inside the tubular body, when pressure is applied between the resistor and the first electrode. First, the pressure is released by the movement of the first electrode inside the cylindrical body. Further, since the stopper is provided so as to surround the cylindrical body, the first electrode moves and collides with the stopper, thereby preventing scattering of the first electrode.

[0029]

【Example】

Embodiment 1 FIG. 1 is a sectional view showing the structure of a lightning arrester which is Embodiment 1 of the present invention, and FIG. 2 is a plan view of FIG. In FIGS. 1 and 2, reference numeral 5 denotes a cylindrical voltage nonlinear resistor (hereinafter simply referred to as a resistor) made of a sintered body containing zinc oxide as a main component. Reference numeral 6 is a cylindrical body made of metal such as aluminum, and has a large-diameter opening 6a having one end fixed to one end surface of the resistor 5 with an adhesive or the like (not shown), and a large-diameter opening 6a at the other end. It has a cover 6c as a stopper having a small diameter opening 6b concentrically with 6a, and a notch 6d as a rupture portion at the outer peripheral end of the cover 6c. Reference numeral 7 denotes a Z-shaped compression spring conductor made of a conductive metal, one of which is electrically connected to the resistor 5 and the other of which is electrically connected to an electrode 8 described later with respect to at least one end surface of the resistor 5.

Reference numeral 8 is a first electrode housed so as to be movable inside the cylindrical body 6, and is a disk-shaped electrode portion having a locking portion 8a facing the resistor 5 and locking the conductor 7. 8b, which protrudes from this electrode portion 8b and penetrates through the small-diameter opening 6b to cover 6
It has an external terminal portion 8c protruding from c. Reference numeral 9 is a void formed between the resistor 5 and the electrode portion 8b, and 10 is a packing provided between the outer peripheral surface of the electrode portion 8b and the inner peripheral surface of the large-diameter opening 6a of the tubular body 6, The void 9 is sealed. The large-diameter opening 6a of the tubular body 6 is continuous with an opening having a slightly smaller diameter, and a step 6e between the two openings causes
The movement of the electrode 8 having the packing 10 against the compression spring conductor 7 is blocked and held. The cylindrical body 6, the second electrode 8, and the compression spring conductor 7 are provided on the other end surface of the resistor 5, similarly to the one end surface. Reference numeral 11 is a mold insulator that surrounds the outer peripheral surface of the resistor 5 and a part of the outer peripheral surfaces of both the tubular bodies 6 and 6 and is made of epoxy resin or the like by casting. The resistor 5, the tubular body 6, the conductor 7, the electrode 8, the packing 10, and the mold insulator 11 constitute a lightning arrester 12.

Next, the operation will be described. When an overvoltage such as a lightning surge or a switching surge is applied to the electrode 8, a large current flows through the resistor 5. When the lightning arrester 12 exceeds the discharge withstand capability, the resistor 5 is destroyed, and an arc discharge is generated inside or inside the resistor 5. For this reason, the resistor 5 instantly becomes high in temperature and abruptly thermally expands to a high pressure. The pressure increase due to this high pressure is caused by the solid resistor 5
The void portion 9 which is a gas is transmitted faster than the void portion 9.
Then, when the pressure at the void 9 becomes greater than the holding force of the packing 10 that seals the void 9, the packing 10 bursts, and the electrode of the electrode 8 that is unsupported by the burst of the packing 10. The portion 8b is moved to the cover 6c side of the tubular body 6.

As a result, the electrode portion 8b collides with the inner surface of the cover 6c, and the notch 6d, which weakens the mechanical strength, ruptures and is generated in the resistor 5 as shown by the arrow A in FIG. Release high pressure. At this time, the cover stays in the open state as shown in FIG. 3, so that the electrode 8 is prevented from scattering. In this way, the lightning arrester 12 can reduce the power of explosion and prevent scattering of the components of the lightning arrester 12, such as the resistor 5, the tubular body 6, the conductor 7, the electrode 8, and the mold insulator 11.

Even if the surge arrester 12 has an overvoltage such as a lightning surge or a switching surge that is less than or equal to the discharge withstand voltage, the surge arrester 12 receives the overvoltage repeatedly or due to deterioration over time, or the tubular body 6 and the mold insulator 11 are deteriorated. Between, and electrode 8
A gap is created between the mold insulator 11 and the mold insulator 11. Even if rainwater enters the gap and causes an insulation breakdown and explodes,
The same operational effect as that of the first embodiment is obtained.

Further, in FIG. 1, the cover 6c of the tubular body 6 has a notch 6d at the outer peripheral end thereof, but the notch 6d may be provided at another portion of the cover 6c.

The conductor 7 is replaced by a Z-shaped compression spring,
A compression spring such as a coil spring may be used.

When the lightning arrester 12 is used outdoors,
The small-diameter opening 6b of the tubular body 6 and the external terminal portion 8c of the electrode 8
A packing 13 as a sealing member as shown in FIG. 4 may be provided between the small-diameter opening portion 6b and the external terminal portion 8c in order to prevent rainwater or the like from entering through the gap between and.

Further, in FIGS. 1 and 4, the conductor 7 and the electrode 8 are provided at both ends of the resistor 5, but as shown in FIG. 5, the conductor 7 is provided at one end of the resistor 5. The electrode 8 electrically connected via the electrode 8 is provided, and the electrode 8 is directly electrically connected to the other end to connect the outer peripheral surface of the resistor 5 and a part of the outer peripheral surface of the tubular body 6 and a part of the electrode 8 at the other end. It may be surrounded by the mold insulator 11.

Example 2. FIG. 6 is a sectional view showing the structure of a lightning arrester according to a second embodiment of the present invention. In FIG. 6, 5 and 7 to 11 are the same as those in the first embodiment. Reference numeral 14 denotes a cylindrical body made of metal, such as aluminum, which has a large-diameter opening 14a whose one end is fixed to one end surface of the resistor 5 with an adhesive or the like (not shown) and which has a large-diameter opening at the other end. 14
It has a cover 14c as a stopper having a small diameter opening 14b concentrically with a. The cover 14c corresponds to a thin portion as a burst portion. The other end face of the resistor 5 has the same cylindrical body 14, electrode 8, and conductor 7 as the one end face.
Is provided. It should be noted that the resistor 5, the conductor 7, the electrode 8, the packing 10, the mold insulator 11 and the tubular body 14 constitute a lightning arrester 15.

With the above-mentioned structure, the high pressure generated in the resistor 5 due to the dielectric breakdown due to the overvoltage such as the lightning surge or the switching surge has the same action as that of the first embodiment, and the tubular shape is obtained. The thin portion (corresponding to the cover 14c) of the body 14 ruptures similarly to the tubular body 6 shown in FIG. Therefore,
The lightning arrestor 15 reduces the power of the explosion, the resistor 5, the electrode 6,
Lightning arrester 1 including conductor 7, molded insulator 11, tubular body 14, etc.
5 can be prevented from scattering.

When the lightning arrester 15 is used outdoors,
In order to prevent rainwater and the like from entering through the gap between the small diameter opening 14b of the tubular body 14 and the external terminal portion 8c of the electrode 8, as shown in FIG. 7, between the small diameter opening 14b and the external terminal portion 8c. You may provide the packing 16 as a different sealing member.

Further, in FIGS. 6 and 7, the conductor 7 and the electrode 8 are provided at both ends of the resistor 5, but as shown in FIG. 5, the conductor 7 is provided at one end of the resistor 5. An electrode 8 electrically connected through the electrode 8 is provided, the electrode 8 is directly electrically connected to the other end, and the outer peripheral surface of the resistor 5 and a part of the outer peripheral surface of the tubular body 14 and a part of the electrode 8 are molded insulators. You may be surrounded by 11.

Example 3. FIG. 8 is a sectional view showing the structure of a lightning arrester according to a third embodiment of the present invention. In FIG. 8, 5 and 7 to 11 are the same as those in the first embodiment. Reference numeral 17 denotes a cylindrical body made of metal, such as aluminum, which has a large-diameter opening 17a whose one end is fixed to one end surface of the resistor 5 with an adhesive or the like (not shown), and has a large-diameter opening at the other end. It has a cover 17c having an opening 17b having a small diameter concentrically with 17a, and at least one pressure release port 17d provided on the cover 17c side of the tubular electrode portion 8b. The other end face of the resistor 5 is also provided with the cylindrical body 17, the conductor 7, and the electrode 8 similar to the one end face. In addition, the resistor 5, the conductor 7,
The lightning arrester 18 is composed of the electrode 8, the packing 10, the mold insulator 11 and the tubular body 17.

Next, the operation will be described. When an overvoltage such as a lightning surge or a switching surge is applied to the electrode 8, a large current flows through the resistor 5. When the lightning arrester 18 exceeds the discharge withstand capability, the resistor 5 is destroyed, and an arc discharge is generated inside or inside the resistor 5. For this reason, the resistor 5 instantly becomes high in temperature and abruptly thermally expands to a high pressure. The pressure increase due to this high pressure is caused by the solid resistor 5
The void portion 9 which is a gas is transmitted faster than the void portion 9.
When the pressure at the void 9 becomes equal to or higher than the holding force of the packing 10 that seals the void 9, the packing 10 ruptures, and the electrode 8 that is unsupported by the rupture of the packing 10 is removed. The tubular body 17 is moved to the cover 17c side.

As a result, the electrode portion 8b moves inside the cylindrical body 17 to open the pressure release port 17d of the cylindrical body 17, and the high pressure generated in the resistor 5 as shown by the arrow B in FIG. Since the pressure is released, the power of explosion of the lightning arrester 18 is reduced. Then, the moved electrode portion 8b collides with the inner surface of the cover 17c and stops, and it is possible to prevent the constituents of the lightning arrester 18, such as the resistor 5, the conductor 7, the electrode 8, the mold insulator 11 and the tubular body 17, from scattering. it can.

In addition, even if the surge arrester 18 is applied with an overvoltage such as a lightning surge or a switching surge that is less than the discharge withstand voltage, the surge arrester 18 receives the overvoltage repeatedly or due to deterioration over time, and the tubular body 18 and the mold insulator 11 are deteriorated. Even when a gap is formed between the electrode 8 and the mold insulator 11, and rainwater enters the gap and causes an insulation breakdown to explode, the same effect as that of the first embodiment is obtained.

When the lightning arrester 18 is used outdoors,
In order to prevent rainwater and the like from entering through the gap between the small-diameter opening 17b of the tubular body 17 and the external terminal portion 8c of the electrode 8, as shown in FIG. 10, between the small-diameter opening 17b and the external terminal portion 8c. You may provide the packing 19 as a different sealing member.

Furthermore, in FIG. 8 and FIG.
And the electrodes 8 provided at both ends of the resistor 5 are shown.
As shown in FIG. 5, an electrode 8 electrically connected via the conductor 7 is provided at one end of the resistor 5, and the electrode 8 is directly electrically connected at the other end, and the outer peripheral surface of the resistor 5 and the tubular body 17 are connected. A part of the outer peripheral surface and a part of the electrode 8 at the other end may be surrounded by the mold insulator 11.

Example 4. FIG. 11 is a sectional view showing the structure of a lightning arrester according to a fourth embodiment of the present invention. In FIG. 11, 5
Is the same as that of the first embodiment. Reference numeral 20 is a tubular body made of metal such as aluminum or conductive rubber, and is a resistor 5
Has a large-diameter opening 20a, one end of which is fixed with an adhesive or the like (not shown) to one of the end faces, and has a small-diameter opening 20b concentrically with the large-diameter opening 20a at the other end. A narrow cover 20c is provided between the small diameter opening 20a and the small diameter opening 20b.

Reference numeral 21 denotes an electrode, which is housed so as to be movable inside the tubular body 20 and is electrically connected to one end surface of the resistor 5. The electrode 21 further has a disc-shaped electrode portion 21b having a pressure release hole 21a coaxially with the resistor 5, the electrode portion 21b is provided so as to project and penetrate the small-diameter opening 20b to form the pressure release hole 21a. The small diameter opening 20 is concentrically communicated with and bent.
It has an external terminal portion 21d having a pressure release hole 21c facing b. The pressure release holes 21a and 21c have a cylindrical body 20 with an electrode portion 21b.
When it moves inside and protrudes from the small-diameter opening 20b, it is opened to form a pressure release path. Reference numeral 22 denotes an electrode, which has a disc-shaped electrode portion 22a soldered to the other end surface of the resistor 5 and a round-bar-shaped external terminal portion 22b that is provided concentrically with the electrode portion 22a. . A mold insulator 23 surrounds the outer peripheral surface of the resistor 5 and a part of the outer peripheral surface of the tubular body 20 and a part of the electrode 22, and is made of epoxy resin or the like formed by casting. Incidentally, the resistor 5, the tubular body 20, the electrode 2
The lightning arrester 24 is composed of the first and second 22 and the molded insulator 23.

Next, the operation will be described. When an overvoltage such as a lightning surge or a switching surge is applied to the electrode 21 or the electrode 22, a large current flows through the resistor 5. When the surge arrester 24 exceeds the discharge withstand capability, the resistor 5 breaks down and arc discharge occurs on the inside or inside of the resistor 5. For this reason, the resistor 5 instantly becomes high in temperature and abruptly thermally expands to a high pressure.

As a result, the electrode portion 21b moves inside the tubular body 20 to open the pressure release holes 21a and 21c of the electrode 21 to form a pressure release path, as shown by an arrow C in FIG. Since the high pressure generated in the resistor 5 is released, the power of explosion of the lightning arrester 24 is reduced. Then, the moved electrode portion 21b
Can be stopped by colliding with the inner surface of the cover 20c, and scattering of the components of the arrester 24 such as the resistor 5, the tubular body 20, the electrodes 21, 22, and the mold insulator 23 can be prevented.

Further, the lightning arrester 24 has the tubular body 20 and the mold insulator 23 when the overvoltage such as the applied lightning surge or open / close surge is less than the discharge withstand voltage, when the overvoltage is repeatedly received or due to deterioration over time. Even when a gap is formed between the electrode 22 and the mold insulator 23, and rainwater enters the gap and causes an insulation breakdown and explodes, the same effect as that of the first embodiment is obtained.

When conductive rubber is used for the tubular body 19, the epoxy resin is hardened at 120 ° C., for example, when the lightning arrester 24 is manufactured, as compared with the case where a metal such as aluminum is used for the tubular body 19. When cooled at room temperature 20 ° C,
Since the stress generated between the tubular body 20 and the mold insulator 22 is about ⅕, it is possible to suppress the occurrence of cracks in the mold insulator 23, and it is possible to manufacture a lightning arrester with good insulation.

Further, in FIG. 11, the cylindrical body 20 and the electrode 2 are
1 is provided at one end of the resistor 5 and the electrode 22 is provided at the other end, but the cylindrical body 20 and the electrode 2 are provided at both ends of the resistor 5.
1 is provided, and the outer peripheral surface of the resistor 5 and the cylindrical bodies 20, 20 at both ends are provided.
A part of the outer peripheral surface of the above may be surrounded by the mold insulator 23.

Furthermore, when the lightning arrester 24 is used outdoors, in order to prevent rainwater or the like from entering through the gap between the small-diameter opening 20b of the tubular body 20 and the external terminal portion 21d of the electrode 21, the small-diameter opening 20b is provided. Between the external terminal portion 21d and
You may provide the packing 25 as a sealing member as shown in FIG.

Example 5. FIG. 14 is a fifth embodiment of the present invention.
2 is a cross-sectional view showing the configuration of the lightning arrester. In FIG.
5 and 7 to 10 are the same as those in the first embodiment. Reference numeral 26 is a cylindrical body made of metal such as aluminum, and has a large diameter opening 26a whose one end is fixed to one end surface of the resistor 5 with an adhesive or the like (not shown), and the other end has a slightly smaller diameter. The openings are continuous, and the step 26 between the openings is
By b, the movement of the electrode 8 having the packing 10 against the compression spring conductor 7 is blocked and held. Reference numeral 27 denotes an insulating cylinder made of an insulating material such as epoxy resin, which has a large-diameter opening 27a on one side so as to surround the outer periphery of the cylindrical body 26 and is concentric with the large-diameter opening 27a at the other end. It has a cover 27c as a stopper having an opening 27b having a small diameter larger than the external terminal portion 8c of the electrode 8. A discharge gap, which is connected to an insulator (not shown) coaxially with the small-diameter opening 27b, is provided on the outer side of the insulating cylinder 27. A discharge arc is formed between them and a large current flows. Reference numeral 28 denotes a mold insulator surrounding the outer peripheral surface of the resistor 5 and a part of the insulating cylinder 27 and a part of the electrode 8 and made of epoxy resin or the like formed by casting. The resistor 5, the conductor 7, the electrode 8, the packing 10, the cylindrical body 26, the insulating cylinder 27, and the mold insulator 28 constitute a lightning arrester 29.

Next, the operation will be described. When a large current flows through the resistor 5 through the electrode 8 and the conductor 7 due to an overvoltage such as a lightning surge, when the lightning arrester 29 exceeds the discharge withstand capability, the resistor 5 is destroyed, and an arc is generated inside or inside the resistor 5. Electric discharge occurs. Therefore, the resistor 5 instantly becomes high in temperature and undergoes rapid thermal expansion to become high pressure. The pressure increase due to this high pressure is transmitted faster in the void portion 9 which is a gas than in the resistor 5 which is a solid. Then, when the pressure at the void 9 becomes equal to or higher than the holding force of the packing 10 that seals the void 9, the packing 10 ruptures, and the rupture of the packing 10 makes the electrode 8 unsupported.
The electrode part 8b is moved to the cover 27c side of the insulating cylinder 27 inside the cylindrical body 26 to release the high pressure generated in the resistor 5. Further, since the electrode portion 8b collides with the inner surface of the cover 27c and stays there, scattering of fragments of the electrode 8 and the resistor 5 and the like is prevented.

[0058]

Since the present invention is configured as described above, it has the following effects.

The tubular body is fixed to the resistor, and the first electrode electrically connected to one end of the resistor is housed so as to be movable inside the tubular body. When pressure is applied between the first electrode and the electrode, the first electrode moves inside the cylindrical body to release the pressure, and it is possible to prevent scattering of debris such as resistors scattered in the cylindrical body to the outside. it can.

When pressure is applied between the resistor and both electrodes, the first electrode moves inside the tubular body to release the pressure and collides with the stopper, so that the first electrode is tubular. It is possible to prevent separation from the state.

When pressure is applied between the resistor and the first electrode, the first electrode moves inside the tubular body and collides with the ruptured portion of the tubular body. As a result, the pressure can be released and the first electrode can be prevented from separating from the tubular body.

Since the notch is provided at the rupture portion,
When pressure is applied between the resistor and the first electrode, when the first electrode moves inside the tubular body and collides with the ruptured portion of the tubular body, the ruptured portion is easily ruptured and pressure is applied. Can be released early to reduce the power of the explosion.

Since the thin portion is provided at the rupture portion,
When pressure is applied between the resistor and the first electrode, when the first electrode moves inside the tubular body and collides with the ruptured portion of the tubular body, the ruptured portion is easily ruptured and pressure is applied. Can be released early to reduce the power of the explosion.

Further, when pressure is applied between the resistor and the first electrode, the first electrode moves inside the cylindrical body to form the discharge path, so that the pressure can be discharged. And
When the moved first electrode collides with the stopper, it is possible to prevent the first electrode from coming off the tubular body.

Further, since the pressure releasing port is provided in the tubular body as the releasing means, the first electrode moves inside the tubular body when pressure is applied between the resistor and the first electrode. By releasing the pressure relief port of the cylindrical body to release the pressure, the power of the explosion can be reduced.

Further, since the pressure releasing port is provided in the first electrode as the discharging means, the first electrode moves inside the cylindrical body when pressure is applied between the resistor and the first electrode. The pressure release port of the first electrode is opened to release the pressure, and the power of the explosion can be reduced.

Further, since the sealing member is provided between the electrode and the cylindrical body, it is possible to prevent rainwater from entering and suppress deterioration of insulation of the lightning arrester.

Furthermore, since the first electrode electrically connected to one end of the resistor is housed so as to be movable inside the tubular body, pressure is applied between the resistor and the first electrode. At times, the pressure can be released by moving the first electrode inside the tubular body. Further, since the stopper is provided so as to surround the cylindrical body, it is possible to prevent the first electrode from scattering due to the movement of the first electrode and the collision with the stopper.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a lightning arrester according to a first embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a cross-sectional view showing a main part at the time of releasing pressure in FIG.

FIG. 4 is a sectional view showing a modification of FIG.

FIG. 5 is a sectional view showing another modification of FIG. 1;

FIG. 6 is a cross-sectional view showing a configuration of a lightning arrester according to a second embodiment of the present invention.

7 is a cross-sectional view showing a modified example of FIG.

FIG. 8 is a cross-sectional view showing a configuration of a lightning arrester according to a third embodiment of the present invention.

9 is a cross-sectional view showing a main part at the time of releasing pressure in FIG.

10 is a cross-sectional view showing a modified example of FIG.

FIG. 11 is a cross-sectional view showing the configuration of the lightning arrester of Embodiment 4 of the present invention.

FIG. 12 is a cross-sectional view showing a main part at the time of releasing pressure in FIG.

FIG. 13 is a cross-sectional view showing the main parts of the modified example of FIG.

FIG. 14 is a cross-sectional view showing the structure of the lightning arrester of Embodiment 5 of the present invention.

FIG. 15 is a sectional view showing a configuration of a conventional lightning arrester.

FIG. 16 is a plan view of FIG.

[Explanation of symbols]

 5 Voltage Non-Linear Resistor 6,14,17,20,26 Cylindrical Body 6c, 14c, 17c, 20c, 27c Cover 6d Notch 8,21,22 Electrode 8b, 21b, 22a Electrode 8c, 21d, 22b External Terminal part 11,23,28 Mold insulator 13,16,19,25 Packing 17d Pressure release port 21a, 21c Pressure release hole 27 Insulation cylinder

Claims (10)

[Claims] 1. A voltage non-linear resistor, a cylindrical body fixed with respect to the voltage non-linear resistor, a movable body housed so as to be movable inside the cylindrical body, and an electric wire is provided at one end of the voltage non-linear resistor. The first electrode connected, the second electrode electrically connected to the other end of the voltage nonlinear resistor, and the first electrode when pressure is applied between the voltage nonlinear resistor and the first electrode A lightning arrester provided with a discharge means that moves inside the cylindrical body to discharge pressure. 2. The first electrode which moves inside the tubular body to release the pressure when pressure is applied between the voltage non-linear resistor and both electrodes is the tubular body. The lightning arrester according to claim 1, further comprising a stopper that prevents the lightning arrestor from being separated from the lightning arrester. 3. A voltage non-linear resistor, a tubular body having one end fixed to the voltage non-linear resistor and a cover at the other end,
A first electrode having an electrode portion housed so as to be movable inside the tubular body and electrically connected to one end of the voltage nonlinear resistor; and an external terminal portion protruding from the electrode portion and protruding from the cover. One electrode, a second electrode electrically connected to the other end of the voltage nonlinear resistor, the first electrode is the tubular body when pressure is applied between the voltage nonlinear resistor and the first electrode A rupture portion provided on the tubular body that ruptures by moving inside to release the pressure, and the first electrode that moves inside the tubular body and releases the pressure is the tubular body. A lightning arrester comprising a stopper provided on the tubular body for preventing the tubular body from being detached from the cylindrical body, and a mold insulator surrounding the voltage nonlinear resistor and the tubular body. 4. The arrester according to claim 3, wherein the rupture portion has a cutout portion. 5. The arrester according to claim 3, wherein the rupture portion has a thin portion. 6. A voltage non-linear resistor, a tubular body having one end fixed to the voltage non-linear resistor and a cover at the other end,
A first electrode having an electrode portion housed so as to be movable inside the tubular body and electrically connected to one end of the voltage nonlinear resistor; and an external terminal portion protruding from the electrode portion and protruding from the cover. One electrode, a second electrode electrically connected to the other end of the voltage nonlinear resistor, the first electrode is the tubular body when pressure is applied between the voltage nonlinear resistor and the first electrode The discharge means for discharging the pressure by forming the discharge path by moving inside the tube, and the first electrode moving inside the cylindrical body and discharging the pressure to separate from the cylindrical body. A lightning arrester comprising a stopper provided on the cylindrical body for blocking, and a mold insulator surrounding the voltage nonlinear resistor and the cylindrical body. 7. The lightning arrester according to claim 6, wherein the cylindrical body is provided with a pressure release port as the release means. 8. The arrester according to claim 6, wherein the first electrode is provided with a pressure release hole as the emission means. 9. The lightning arrester according to claim 1, further comprising a sealing member that prevents rainwater from entering between the first electrode and the tubular body. 10. A voltage non-linear resistor, a tubular body fixed to the voltage non-linear resistor, and a movably accommodated inside the tubular body. The first electrode connected, the second electrode electrically connected to the other end of the voltage nonlinear resistor, the first electrode when the pressure is applied between the voltage nonlinear resistor and the first electrode A discharge means that moves inside the tubular body to release the pressure, and a surrounding the tubular body that prevents the first electrode that moves to release the pressure from scattering the first electrode. Lightning arrester with a stopper provided.