JP2020004579A - Surge protection element - Google Patents

Abstract

To provide a surge protection element, which can be manufactured at a low cost, capable of suppressing short circuit due to adhesion of metal components scattered by arc discharge.SOLUTION: The surge protection element includes: an insulating tube 2; a pair of sealing electrodes 3 for closing both end openings of the insulating tube and sealing a discharge control gas therein; and an interval adjusting member 4 for defining an interval between the pair of sealing electrodes, by being sandwiched between opposing surfaces of the pair of sealing electrodes vertically arranged in a state where a part is left open as a discharge space S between the pair of sealing electrodes. The interval adjusting member includes at least one insulating thin plate 6 formed of an insulating material. A peripheral edge portion 6a of the insulating thin plate in contact with the discharge space S has a groove 6b extending along the discharge space at least on one of upper and lower surfaces. A discharge space side (wall portion 6c) of wall portions 6c and 6d on both sides constituting the groove is lower than the opposite wall portion 6d.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a surge protection element used to protect various devices from a surge generated by a lightning strike or the like and prevent an accident from occurring.

  Telecommunications equipment such as telephones, facsimiles, modems, etc., connected to communication lines, power lines, antennas or image display drive circuits such as CRTs, liquid crystal televisions and plasma televisions, abnormal voltages such as lightning surges and static electricity A surge protection element is connected to a part which is easily affected by electric shock due to (surge voltage) in order to prevent an electronic device or a printed circuit board on which the device is mounted from being damaged by heat or fire due to abnormal voltage.

  2. Description of the Related Art Conventionally, for example, Patent Literature 1 describes a microgap type surge protection element in which a member covered with conductive coating is sandwiched between metal members facing each other in a glass tube. This micro-gap type surge protection element has a structure in which a slit (gap) of several μm to several tens μm is provided at the center of a conductively coated member, and no current flows between opposing metal members below a specified voltage. . When the voltage exceeds the set voltage, an arc discharge occurs between the slits, and a current flows between the opposed metal members.

This surge protection element is a device that utilizes the shape changeability of a glass tube due to softening of glass and the characteristics of joining with a metal, and has excellent mass productivity, and is therefore used in a wide range of fields.
In addition, Patent Document 2 discloses a surge protection device including a cylindrical body formed of ceramics or glass, and a pair of electrodes facing each other with a predetermined space therebetween by interposing an electrically insulating ring-shaped spacer. An element is described. A surge protection element in which the opposing electrode is sealed with a ceramic cylindrical body such as alumina as in such a surge protection element is called an arrester.

JP-B-63-57918 JP-A-63-318085

The following problems remain in the above-described conventional technology.
In other words, the glass-coated microgap surge protection element has good bonding properties between glass and metal members, and has excellent reliability such as gas sealing properties and air and moisture blocking properties. However, since the slit width constituting the microgap is small and the thickness of the conductive coating forming the periphery of the microgap is as thin as several tens of μm, the surge withstand capability is limited to about 1500A. In addition, a film forming step of a conductive coating and a laser processing step for forming a micro gap are required, so that the steps become complicated, the production takes time, and the cost is increased.
On the other hand, the arrester-type surge protection element has a withstand capacity of 2000A for a product with a diameter of 5 mm and a resistance of 5000 A for a product with a diameter of 8 mm, and has a surge withstand characteristic higher than that of a glass-coated micro gap type surge protector. I have. Such an arrester-type surge protection element is used for infrastructure equipment such as large home appliances, solar power generation, and water and sewage that require high reliability. The arrester-type surge protection element requires an expensive bonding agent (silver-based brazing material) and an alumina cylindrical member that is more expensive than a glass cylindrical member in joining metal and ceramics. In addition, very high technology is required for joining ceramics and metal parts, and an auxiliary electrode material (such as graphite) is provided inside the electrode, and a dielectric material is applied to the surface of the counter electrode for the purpose of protecting the electrode and promoting discharge. And the production process is complicated. Therefore, the manufacturing cost tends to be significantly higher than that of the glass-coated micro gap type surge protection element. In particular, in the case of using for countermeasures against static electricity, it is necessary to separate electrodes facing each other at a very small interval such as the above-mentioned micro gap, and it has been difficult to set the gap with high accuracy.
Further, there is a problem in that the metal constituting the electrode portion is melted and scattered by the arc discharge, and the metal component adheres to the inner surface of the insulating tube, thereby deteriorating the insulating property between the pair of sealing electrodes. In particular, if a large amount of metal component adheres to the inner surface of the insulating tube, a current-carrying circuit may be formed on the inner peripheral surface of the insulating tube, causing a short circuit.In such a case, the life of the surge protection element is determined. There was an inconvenience. In the surge protection element described in Patent Document 2, the metal component does not adhere to the inner peripheral surface of the insulating tube because the ring spacer is interposed, but the metal component adheres to the inner peripheral surface of the ring spacer. As a result, there was a risk that a short circuit would occur.

  The present invention has been made in view of the above-described problems, and has an object to provide a surge protection element that can be manufactured at low cost and that can suppress a short circuit due to adhesion of a metal component scattered by arc discharge. .

  The present invention has the following features to attain the object mentioned above. That is, a surge protection element according to a first aspect of the present invention includes an insulating tube, a pair of sealing electrodes for closing both ends of the insulating tube to seal a discharge control gas therein, and a pair of the sealing electrodes. A gap adjusting member that is interposed between opposing surfaces of the pair of sealing electrodes arranged vertically above and below a part of the stopping electrodes as a discharge space and defines a gap between the pair of sealing electrodes. The gap adjusting member includes at least one insulating thin plate formed of an insulating material, and a peripheral edge portion of the insulating thin plate in contact with the discharge space extends along at least one of upper and lower surfaces along the discharge space. Wherein the discharge space side is lower than the opposite wall portion among the wall portions on both sides constituting the groove portion.

In this surge protection element, the peripheral portion of the insulating thin plate that contacts the discharge space has a groove extending along the discharge space on at least one of the upper and lower surfaces, and the discharge space side of the walls on both sides constituting the groove is formed. , Since the metal component scattered by the arc discharge adheres to the wall portion of the insulating thin plate because it is lower than the opposite wall portion, it is difficult to form an energized circuit by the adhered metal, and it is possible to suppress a short circuit. it can. That is, since the groove which becomes a shadow of the wall is formed in the peripheral portion of the insulating thin plate, the wall makes it difficult for metal components to adhere to the groove. In addition, since the discharge space side is lower than the opposite wall among the walls on both sides constituting the groove, a gap is formed between the wall on the discharge space side and the sealing electrode or another member vertically stacked. This can prevent a short circuit even if a metal component adheres to the wall.
In addition, the creepage distance between the sealing electrodes via the peripheral edge of the insulating thin plate becomes longer due to the groove and the wall of the peripheral edge, and in this respect, it is difficult to form a current-carrying circuit by the adhered metal. In the conventional spacer, since the peripheral portion is a peripheral surface parallel to the axis of the insulating tube, the creepage distance between the sealing electrodes is short, and a current-carrying circuit using an attached metal is easily formed.
Further, by using the arrester-type counter electrode, high durability and high reliability can be obtained while being small.

A surge protection element according to a second aspect is characterized in that, in the first aspect, the wall on the discharge space side is inclined toward the bottom of the groove.
That is, in this surge protection element, since the wall on the discharge space side is inclined toward the bottom of the groove, the bottom of the groove becomes more shadowed by the inclined wall, and the metal component into the groove is formed. Can be further suppressed.

In the surge protection element according to a third aspect, in the first or second aspect, the insulating tube has a cylindrical shape, and the plurality of thin plate members have an outer peripheral edge formed on an inner peripheral surface of the insulating tube. It is characterized in that it is formed in an annular shape in contact.
That is, in this surge protection element, since the plurality of thin plate members are formed in an annular shape in which the outer peripheral edge is in contact with the inner peripheral surface of the insulating tube, the thin plate member is in contact with the inner peripheral surface of the insulating tube. By being annular, positioning can be performed, and a discharge space surrounded by a plurality of walls can be secured inside the interval adjusting member.

A surge protection element according to a fourth aspect is the surge protection element according to the first or second aspect, wherein the insulating tube has a cylindrical shape, and the gap adjusting member is disposed at a central portion of the facing surface. The thin plate member is formed in a disk shape having a common axis.
That is, in this surge protection element, the interval adjusting member is disposed at the center of the opposing surface, and the plurality of thin plate members are formed in a disk shape having a common axis. A discharge space can be secured. Further, the gap adjusting member disposed at the center portion of the facing surface serves as a barrier, so that it is possible to suppress the metal component scattered by the arc discharge from scattering to the discharge space on the opposite side in the radial direction of the insulating tube.

A surge protection element according to a fifth aspect of the present invention is the surge protection element according to any of the first to fourth aspects, wherein the interval adjusting member is overlapped in an axial direction of the insulating tube, and at least one of the plurality is a thin insulating plate. A peripheral portion of the thin plate member, which is in contact with the discharge space, has a groove extending along the discharge space on at least one of the upper and lower surfaces, and a wall portion on both sides forming the groove portion The discharge space side is lower than the opposite wall portion.
That is, in this surge protection element, the interval adjusting member is formed of a plurality of thin plate members that are overlapped in the axial direction of the insulating tube, at least one of which is an insulating thin plate and has a groove and a wall. It is more difficult to form an energizing circuit by the adhered metal, and it is possible to suppress a short circuit.
Further, the gap between the pair of sealing electrodes can be easily adjusted by the number of the thin plate members, so that the manufacturing is easy and the cost is low.

The surge protection element according to a sixth aspect is characterized in that, in the fifth aspect, the gap adjusting member includes a functional thin plate as the thin plate member formed of a conductive material.
That is, in this surge protection element, since the gap adjusting member includes the functional thin plate which is a thin plate member formed of a conductive material, the insulating thin plate ensures insulation between the sealing electrodes and the conductive thin plate. The discharge characteristics can be adjusted by the functional thin plate having the property.

A surge protection element according to a seventh aspect is based on the sixth aspect, wherein the functional thin plate is formed of a metal.
That is, in this surge protection element, since the functional thin plate is formed of a metal, the scattered metal component easily adheres to the functional thin metal plate, and it is possible to suppress the metal component from adhering to the insulating thin plate.

The surge protection element according to an eighth aspect is characterized in that, in the sixth aspect, the functional thin plate is formed of an ion source material.
That is, in this surge protection element, since the functional thin plate is formed of the ion source material, it can be a functional thin plate having a discharge auxiliary function as a trigger of arc discharge.

A surge protection element according to a ninth invention is characterized in that, in any one of the first to eighth inventions, the insulating thin plate contains conductive particles in an insulating material.
That is, in this surge protection element, the insulating thin plate contains conductive particles in the insulating material, and the conductive thin particles of the ion source material in the insulating thin plate cause the insulating thin plate itself to be subjected to arc discharge. Can have a discharge assist function or the like as a trigger.

A surge protection element according to a tenth aspect is characterized in that, in any one of the first to ninth aspects, the insulating tube is a glass tube.
That is, in this surge protection element, since the insulating tube is a glass tube, it can be manufactured at a lower cost than ceramics such as alumina, and at the same time, has excellent reliability due to high gas sealing property and moisture blocking property. Can be

According to the present invention, the following effects can be obtained.
That is, according to the surge protection element of the present invention, the peripheral edge portion of the insulating thin plate in contact with the discharge space has a groove extending along the discharge space on at least one of the upper and lower surfaces, and both sides constituting the groove are provided. Since the discharge space side of the wall portion is lower than the opposite wall portion, it can be manufactured at low cost, and short-circuiting due to adhesion of metal components scattered by arc discharge can be suppressed.
Therefore, the surge protection device according to the present invention is suitable for a power supply circuit unit and a communication circuit unit of an electric device that requires a small, inexpensive, and highly reliable product. In particular, the surge protection element of the present invention is suitable for a wide range of applications including measures against static electricity for mounting on a substrate.

It is an axial sectional view showing a 1st embodiment of a surge protection element concerning the present invention. FIG. 2 is an exploded perspective view showing the surge protection element in the first embodiment. FIG. 2 is an enlarged sectional view of a main part in the first embodiment. It is an axial sectional view showing a 2nd embodiment of a surge protection element concerning the present invention. It is an exploded perspective view showing a surge protection element in a 2nd embodiment. It is an axial sectional view showing a 3rd embodiment of a surge protection element concerning the present invention. It is an axial sectional view showing a 4th embodiment of a surge protection element concerning the present invention. It is an axial sectional view showing a 5th embodiment of a surge protection element concerning the present invention.

  Hereinafter, a first embodiment of a surge protection element according to the present invention will be described with reference to FIGS. In each drawing used in the following description, the scale is appropriately changed in order to make each member a recognizable or easily recognizable size.

  As shown in FIGS. 1 and 2, the surge protection element 1 of the present embodiment includes an insulating tube 2 and a pair of sealing members for closing the openings at both ends of the insulating tube 2 to seal the discharge control gas therein. The stop electrode 3 and the pair of sealing electrodes 3 are sandwiched between the opposing surfaces of the pair of sealing electrodes 3 arranged above and below with a part of the space being a discharge space S between the pair of sealing electrodes 3. And an interval adjusting member 4 for defining an interval.

The spacing adjusting member 4 includes at least one insulating thin plate 6 formed of an insulating material.
The spacing adjusting member 4 is composed of a plurality of thin plate members that are stacked in the axial direction of the insulating tube 2 and at least one of which is the insulating thin plate 6.
In the present embodiment, the interval adjusting member 4 is configured by stacking two thin plate members, and both of them are the insulating thin plates 6.

A peripheral edge portion 6a of the insulating thin plate 6 which contacts the discharge space S has a groove 6b extending along the discharge space S on at least one of the upper and lower surfaces, and the wall portions 6c, 6d on both sides constituting the groove portion 6b. The wall 6c on the discharge space S side is set lower than the wall 6d on the opposite side.
In the present embodiment, the peripheral portion 6a of the insulating thin plate 6 which is in contact with the discharge space S has the groove 6b only on the upper surface.

The wall 6c on the discharge space S side is inclined toward the bottom of the groove 6b.
In the present embodiment, as shown in FIG. 3, the wall 6c on the side of the discharge space S has a key-shaped cross-section that is folded toward the groove 6b to form a grooved groove 6b. .
Furthermore, in the present embodiment, the inner diameter of each insulating thin plate 6 is set to be the same, but at least one of the plurality of sheets may be set to a different inner diameter.

The insulating tube 2 has a cylindrical shape and is formed of a glass tube of lead glass or the like. Note that the insulating tube 2 is preferably formed of a glass tube which is inexpensive and has excellent sealing properties, but may be formed of a crystalline ceramic material such as alumina.
The plurality of insulating thin plates 6 (thin plate members) are formed in an annular shape in which the outer peripheral edge is in contact with the inner peripheral surface of the insulating tube 2, and the wall portion 6 c of one of the insulating thin plates 6 (thin plate members) and the other are overlapped. A gap is provided between the insulating thin plate 6 (thin plate member).
That is, the groove 6b and the wall 6c extend annularly around the discharge space S.

The discharge control gas sealed in the insulating tube 2 is an inert gas or the like, for example, He, Ar, Ne, Xe, Kr, SF ₆ , CO ₂ , C ₃ F ₈ , C ₂ F ₆ , CF ₄ , H ₂ , atmosphere, etc., and a mixed gas thereof are employed.
The sealing electrode 3 is formed of, for example, a dumet wire, a 42 alloy (Fe: 58 wt%, Ni: 42 wt%), Cu, or the like in a columnar shape.
In the present embodiment, the pair of sealing electrodes 3 enter the inside of the insulating tube 2 to close the openings at both ends.
The base end of the lead wire 5 projecting outward is embedded in each sealing electrode 3.

The thickness and the number of the plurality of insulating thin plates 6 (thin plate members) to be stacked are set such that the thickness of the spacing adjusting member 4 is, for example, 200 to 800 μm. That is, the thickness of the gap adjusting member 4 becomes the distance between the sealing electrodes.
Further, it is preferable that the installation area of the space adjusting member 4 with respect to the facing surface of the sealing electrode 3 be set to 50% or less. That is, the reason why the installation area of the gap adjusting member 4 is set within 50% is that if it exceeds 50%, a sufficient discharge space S cannot be secured.

  As described above, in the surge protective element 1 of the present embodiment, the peripheral edge portion 6a of the insulating thin plate 6 that contacts the discharge space S has the groove 6b extending along the discharge space S on at least one of the upper and lower surfaces. Since the discharge space S side (wall portion 6c) is lower than the opposite wall portion 6d among the wall portions 6c and 6d on both sides constituting the 6b, the metal component scattered by the arc discharge is the wall portion of the insulating thin plate 6. Even if it adheres to 6c, it is difficult to form an energizing circuit by the adhered metal, and it is possible to suppress short circuit.

  That is, since the groove 6b, which becomes a shadow of the wall 6c, is formed in the peripheral edge 6a of the insulating thin plate 6, the metal component hardly adheres to the groove 6b. In addition, since the discharge space S side (wall part 6c) is lower than the opposite wall part 6d among the wall parts 6c and 6d on both sides constituting the groove part 6b, it is vertically overlapped with the wall part 6c on the discharge space side. Since a gap is formed between the sealing electrode 3 and the other insulating thin plate 6, even if a metal component adheres to the wall portion 6c, a short circuit can be prevented.

Further, the creepage distance between the sealing electrodes 3 via the peripheral portion 6a of the insulating thin plate 6 becomes longer due to the groove 6b and the wall portion 6c of the peripheral portion 6a.
In the conventional spacer, since the peripheral portion is a peripheral surface parallel to the axis of the insulating tube, the creepage distance between the sealing electrodes is short, and a current-carrying circuit using an attached metal is easily formed.

Further, by using the arrester-type counter electrode, high durability and high reliability can be obtained while being small.
In particular, since the insulating tube 2 is a glass tube, the insulating tube 2 can be manufactured at a lower cost than ceramics such as alumina, and excellent reliability can be obtained due to a high gas sealing property and a barrier property against moisture and the like.
Further, since the wall 6c on the side of the discharge space S is inclined toward the bottom of the groove 6b, the bottom of the groove 6b becomes more shadowed by the inclined wall 6c, and the metal component into the groove 6b is formed. Can be further suppressed.

Furthermore, since the spacing adjusting member 4 is formed of a plurality of thin plate members which are stacked in the axial direction of the insulating tube 2 and at least one of which is the insulating thin plate 6 and has a groove portion and a wall portion, the gap adjusting member 4 is made of an adhered metal. An energization circuit is more difficult to be formed, and short-circuiting can be suppressed.
Further, the gap between the pair of sealing electrodes 3 can be easily adjusted by the number of the thin plate members (insulating thin plates 6), so that the manufacturing is easy and the cost is low.

  Next, second to fourth embodiments of the surge protection element according to the present invention will be described below with reference to FIGS. In the following description of each embodiment, the same components described in the above embodiment will be denoted by the same reference numerals, and description thereof will be omitted.

The difference between the second embodiment and the first embodiment is that in the first embodiment, the interval adjusting member 4 is configured by stacking a plurality of annular thin plate members (insulating thin plates 6). As shown in FIGS. 4 and 5, the surge protection element 21 according to the second embodiment is configured such that a plurality of disk-shaped thin plate members (insulating thin plates 26) are overlapped to form an interval adjusting member 24. .
That is, in the second embodiment, the interval adjusting member 24 is disposed at the center of the opposing surface of the sealing electrode 3, and the plurality of insulating thin plates 26 are formed in a disk shape having a common axis.

A peripheral portion 26a of the insulating thin plate 26 which is in contact with the discharge space S has a groove 26b extending along the discharge space S on at least one of the upper and lower surfaces, and the wall portions 26c, 26d on both sides constituting the groove 26b. The wall 26c on the discharge space S side is set lower than the wall 26d on the opposite side.
In the second embodiment, the interval adjusting member 24 is configured by two thin plate members (insulating thin plates 26) that are stacked.
By arranging the gap adjusting member 24 at the center of the facing surface in this way, a substantially annular discharge space S is formed outside the gap adjusting member 24.
In the present embodiment, the outer diameter of each insulating thin plate 26 is set to be the same, but at least one of the plurality of sheets may be set to a different outer diameter from the others.

  As described above, in the surge protection element 21 of the second embodiment, the plurality of thin plate members (insulating thin plates 26) arranged in the central portion of the opposing surface of the sealing electrode 3 are formed in a disk shape having a common axis. Since a gap is provided between the wall portion 26c on the discharge space S side of one overlapping thin plate member (insulating thin plate 26) and the other thin plate member (insulating thin plate 26), the gap adjusting member 24 The discharge space S can be secured outside. In addition, the gap adjusting member 24 disposed at the center portion of the facing surface serves as a barrier, so that the metal component scattered by the arc discharge can be prevented from scattering to the discharge space S on the opposite side in the radial direction of the insulating tube 2.

  Next, the difference between the third embodiment and the first embodiment is that, in the first embodiment, all the thin plate members are insulating thin plates 6, whereas in the surge protection element 31 of the third embodiment, As shown in FIG. 6, the interval adjusting member 34 includes an insulating thin plate 6 which is a thin plate member formed of an insulating material, and a functional thin plate 36 which is a thin plate member formed of a conductive material. Is a point.

In particular, in the third embodiment, the functional thin plate 36 is formed of metal.
The functional thin plate 36 is formed of, for example, the same metal as the sealing electrode 3 such as 42 alloy or Cu.
In the present embodiment, the functional thin plate 36 is formed in the same shape as the insulating thin plate 6, and is sandwiched between the pair of insulating thin plates 6 and stacked.

As described above, in the surge protection element 31 of the third embodiment, since the interval adjusting member 34 includes the functional thin plate 36 which is a thin plate member formed of a conductive material, the sealing electrode 3 is formed by the insulating thin plate 6. In addition to ensuring the insulation between them, the discharge characteristics can be adjusted by the functional thin plate 36 having conductivity.
In particular, in the third embodiment, since the functional thin plate 36 is formed of metal, the scattered metal component easily adheres to the metallic functional thin plate 36 and can be suppressed from adhering to the insulating thin plate 6. It is.

Next, the difference between the fourth embodiment and the third embodiment is that, in the third embodiment, the metal functional thin plate 36 is adopted, whereas in the surge protection element 41 of the fourth embodiment, As shown in FIG. 7, the functional thin plate 46 of the gap adjusting member 44 is formed of an ion source material.
That is, the functional thin plate 46 of the fourth embodiment is an annular discharge assisting portion formed of, for example, a carbon material.

In the surge protection element 41, when an overvoltage or an overcurrent enters, an initial discharge is first performed between the functional thin plate 46 serving as a discharge auxiliary portion and the sealing electrode 3, and further discharge is triggered by the initial discharge. As it progresses, an arc discharge is performed from one sealing electrode 3 to the other sealing electrode 3.
Thus, in the surge protection element 41 of the fourth embodiment, since the functional thin plate 46 is formed of the ion source material, it can be a functional thin plate having a discharge auxiliary function as a trigger of arc discharge. .

Next, the difference between the fifth embodiment and the first embodiment is that, in the first embodiment, the interval adjusting section 4 is constituted by insulating thin plates 6 a and 6 b laminated in the axial direction of the insulating tube 2. On the other hand, in the surge protection element 51 of the fifth embodiment, as shown in FIG. 8, the gap adjusting portion 54 is formed by a single insulating thin plate formed on the surface facing one sealing electrode 3. This is a point composed of only 56.
That is, in the fifth embodiment, the gap is constituted only by the thickness of one insulating thin film 56.

Further, the fifth embodiment is different from the first embodiment in that one insulating thin plate 56 constituting the gap adjusting member 54 contains conductive particles C in an insulating material.
That is, the insulating thin plate 56 of the fifth embodiment contains the conductive particles C such as the ion source material in a dispersed state while maintaining the insulating properties as a whole.
For example, the insulating thin plate 56 contains carbon particles as an ion source material as conductive particles C in the insulating material, and some of the conductive particles C are exposed on the inner peripheral surface.

As described above, in the surge protection element 51 of the fifth embodiment, a gap corresponding to the thickness of the insulating thin plate 56 can be provided between the pair of sealing electrodes 3 even with one insulating thin plate 56. .
Further, since the insulating thin plate 56 contains the conductive particles C in the insulating material, the insulating thin plate 56 itself is subjected to arc discharge by the conductive particles C such as the ion source material in the insulating thin plate 56. A discharge assist function or the like as a trigger can be provided.

  Note that the technical scope of the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention.

  1, 21, 31, 41, 51 ... surge protection element, 2 ... insulating tube, 3 ... sealing electrode, 4, 24, 34, 44, 54 ... spacing adjusting member, 6, 66 ... insulating thin plate, 6a, 26a: peripheral portion, 6b, 26b: groove portion, 6c, 6d, 26c, 26d: wall portion, 46, 56: functional thin plate, C: conductive particles, S: discharge space

Claims (10)

An insulating tube;
A pair of sealing electrodes for closing the opening at both ends of the insulating tube and sealing the discharge control gas inside,
An interval adjustment for defining the interval between the pair of sealing electrodes sandwiched between opposing surfaces of the pair of sealing electrodes arranged vertically with a part of the sealing electrodes being left as a discharge space between the pair of sealing electrodes. And a member,
The gap adjusting member includes at least one insulating thin plate formed of an insulating material,
A peripheral portion of the insulating thin plate in contact with the discharge space has a groove extending along the discharge space on at least one of upper and lower surfaces,
The surge protection element according to claim 1, wherein the discharge space side of the wall portions on both sides constituting the groove portion is lower than the opposite wall portion. The surge protection device according to claim 1,
The wall portion on the side of the discharge space is inclined toward the bottom of the groove. The surge protection device according to claim 1 or 2,
The insulating tube is cylindrical,
A surge protection element, wherein the insulating thin plate is formed in an annular shape in which an outer peripheral edge is in contact with an inner peripheral surface of the insulating tube. The surge protection device according to claim 1 or 2,
The insulating tube is cylindrical,
The interval adjusting member is disposed at a central portion of the facing surface,
The said insulating thin plate is formed in the disk shape which the axis line mutually common, The surge protection element characterized by the above-mentioned. The surge protection device according to any one of claims 1 to 4,
The interval adjusting member is constituted by a plurality of thin plate members which are stacked in the axial direction of the insulating tube and at least one of which is the insulating thin plate,
A peripheral portion of the thin plate member contacting the discharge space has a groove extending along the discharge space on at least one of upper and lower surfaces,
The surge protection element according to claim 1, wherein the discharge space side is lower than the opposite wall part among the wall parts on both sides constituting the groove. The surge protection device according to claim 5,
The said gap adjustment member is provided with the functional thin plate which is the said thin plate member formed with the conductive material, The surge protection element characterized by the above-mentioned. The surge protection device according to claim 6,
The said functional thin plate is formed of metal, The surge protective element characterized by the above-mentioned. The surge protection device according to claim 6,
The surge protective element, wherein the functional thin plate is formed of an ion source material. The surge protection device according to any one of claims 1 to 8,
A surge protection element, wherein the insulating thin plate contains conductive particles in an insulating material. The surge protection device according to any one of claims 1 to 9,
2. The surge protection device according to claim 1, wherein the insulating tube is a glass tube.

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