JP2001006839A - Spark discharge gap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent dynamic current, prevent consumption of a spark electrode, and furthermore enhance the performance of a composite low voltage circuit arrester by sloping the opposite surfaces facing slightly downward right and left from a portion of the longitudinal center line on the opposite surfaces. SOLUTION: Metal electrodes 30, 30a of a vertical square rod electrode spark gap 3 are press-inserted into metal electrode tubes 31, 31a, and pressed against the metal electrode tubes 31, 31a with pushing screws 32, 32a from the outside. Screw rods 33, 33a for a lead wire are installed in the metal electrode tubes 31, 31a, the metal electrodes 30, 30a pressed against the metal electrode tubes 31, 31a are faced at the micro distance (m), and fixed to a ceramic fixing board 35 having a recess in the central part with fixing screws 36, 36a. A spark electrode sloping the opposite surfaces facing slightly downward up and down from a portion of the lateral center line is installed in the electrode spark gap 3. As the electrode material, brass, a sintered alloy of copper and tungsten, molybdenum, carbon, and conductive ceramics can be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

When a spark discharge gap is used as a lightning arrester, there is some delay in operation, but since the voltage between the electrodes during discharge is low, even if a large current flows, the power consumption between the spark electrodes is reduced in the case of a shock voltage. Since the electrode is relatively small, the electrode is slightly consumed, so that it has a feature that the electrode can sufficiently withstand an excessively large impact large current.

In a lightning arrester for a composite low-voltage circuit as proposed in Japanese Patent No. 2628736, even when a semiconductor lightning arrester and a spark discharge gap are connected in parallel, both operations can be coordinated, so that both responsiveness and surge withstand capability are improved. An excellent low-voltage surge arrester can be obtained. Therefore, the problem of the operation delay of the spark discharge gap can be solved.

However, when used in a power supply circuit, when an excessive lightning surge arrives and the spark gap operates, a current from the power supply voltage may continuously flow due to a low discharge voltage between the electrodes. . This current is called a continuous flow, and in the case of a continuous flow, unlike a shock current, the current flows continuously, so that the electrode is greatly consumed. The present invention is proposed for the purpose of preventing such follow-up current, preventing the spark electrode from being worn, and further improving the performance of the combined type lightning arrester for low voltage circuit.

[0005]

[Industrial applications]

[0006] The present invention relates to a structure of a spark gap, in which even if a strong lightning surge enters, a spark flow does not cause a wake in the spark gap and the spark gap is not damaged by the wake.

[0007]

[Prior art]

[0008] The spark gap currently used in the compound type low voltage lightning surge arrester is shown in FIG.
A pair of square brass rods 1 and 1a are used facing each other. In this case, the discharge starts on the outer periphery of the facing surface, and the spark tends to spread along the outer periphery line. For this reason,
Since the arc due to the discharge is on the outer periphery of the electrode, the cooling effect by the electrode surface cannot be expected. Further, although a part of the arc enters the gap between the electrodes, the effect that the arc is diffused on the electrode surface is poor because the gap between the electrodes is narrow and parallel.

[0009]

[Problems to be solved by the invention]

That is, in order to prevent the follow-up current, the current is concentrated as much as possible on the electrode surface portions (anode point and cathode point) of the arc to increase the voltage drop between the electrodes, and the arc is diffused or cooled. The purpose is to prevent ionization of air between the electrodes.
Accordingly, it is an object of the present invention to obtain an electrode structure capable of preventing a downstream flow.

Further, in order to prevent the electrode from being worn, it is necessary to select an electrode material. Generally, a brass electrode is used, but an electrode using a copper-tungsten sintered alloy, molybdenum, carbon, a conductive ceramic, or the like can be used to further reduce damage to the electrode due to electric discharge.

[0012]

In order to prevent the follow-up current, the arc at the time of the discharge starts around the outer periphery of the counter electrode and does not run along the outer periphery. It is necessary to make the electrode structure run inside the counter electrode, and the arc running further inside is diffused along the internal electrode surface and cooled between them.

(1) In the spark discharge gap in which a pair of electrodes are opposed to each other, the opposed surfaces are slightly inclined left and right from the position of the vertical center line of each opposed surface. Spark discharge gap. (2) A spark discharge gap in which a pair of electrodes are opposed to each other, wherein the opposed surfaces are slightly inclined upward and downward from the center line beside each opposed surface. And so on.

[0014] In addition, as an electrode material, experience from the past,
We proposed brass, copper-tungsten sintered alloy, molybdenum, carbon, conductive ceramic, etc.

[0015]

[Action]

Regarding the movement of the arc at the time of discharge in the spark discharge gap of the present invention, for example, as shown in FIG. Explain that the discharge starts at one of the upper and lower ends on the vertical center line, and the arc foot (cathode point, anode point) travels along the vertical center line and penetrates into the gap between the opposing electrodes. Since the wall is fan-shaped from the center to the left and right, the arc legs 21, 21a
The (cathode point, anode point) also moves from the center line of the electrode to the left and right surfaces, and current concentrates there, so that the potential drop increases, and the entire arc (22) is sandwiched between the electrodes and receives a cooling action. Since diffusion is performed while preventing ionization (thermal ionization), the formation of a new cathode point (the previous anode point) is also prevented, and the subsequent flow is interrupted.

[0017]

【Example】

FIG. 3 shows one embodiment of the vertical square rod electrode spark gap of the present invention. The metal electrodes 3, 3a of the spark gap main body 3 are press-fitted into metal electrode tubes 31, 31a. , 31a from outside the push screw 32, 3
2a.

The metal tubes 31, 31a are provided with screw rods 33, 33a for lead wires.

The metal electrodes 30, 30a pressed against the metal electrode tubes 31, 31a are opposed to each other with a small gap m.

Further, it is mounted and fixed to mounting bases 35 made of porcelain having a concave portion 34 at the center by mounting screws 36 and 36a.

FIG. 4 relates to a horizontal square bar electrode spark gap 4 having a gap m according to the present invention. 40 and 40a are spark electrodes,
From the location of the horizontal center line, the opposing surface is vertically inclined slightly downward.

[0023]

[Brief description of the drawings]

FIG. 1 shows a conventional spark gap.

FIG. 2 is a view showing the principle of the vertical square rod electrode spark gap of the present invention.

FIG. 3 is a perspective view of a vertical square rod electrode spark gap according to the present invention, in which a metal electrode tube is mounted on the outer periphery of an electrode, and a pair of electrodes pressed against each other are arranged to face each other.

FIG. 4 is a horizontal square bar electrode spark gap showing another embodiment of the present invention.

[Explanation of symbols]

1, square bar electrode spark gap 2, 3, vertical square bar electrode spark gap 4 of the present invention, horizontal square bar electrode spark gap 20, 20a 30, 30a of the present invention vertical square bar electrode 21, 21a arc foot ( (Cathode point, anode point) 22 Arc 31, 31a Metal electrode tube 32, 32a Push screw 33, 33a Screw rod 34 Recess 35 Mounting base 36, 36a Mounting screw 40, 40a Horizontal square rod electrode m Spark gap

[0023]

【The invention's effect】

According to the spark discharge gap of the present invention, the outer periphery of the discharge gap does not become a main discharge point as in the prior art, but the discharge starts almost at the center of the opposing electrode surface. , The anode point) moves from the center of the electrode to the outside on the electrode surface that spreads in a fan shape, so that the cooling and diffusion action is promoted by the electrode surfaces on both sides, and ionization between the electrodes is prevented, Subsequent flow from the power source is unlikely to occur.

Even if a follow-up current of about one or two cycles occurs, the current concentrates on the electrode surface, and the voltage drop in that part also becomes large. Therefore, a new cathode point (the conventional anode point) Is blocked and the following flow is cut off.

In the AC 100 V to 200 V circuit, the vertical current or the horizontal type brass square rod electrode extinguishes the follow current, but in the circuit of 200 V AC or more, it is also considered that about 1 to 2 cycles of the follow current occur. Since a sintered material of copper-tungsten, molybdenum, carbon, conductive ceramic, or the like is used as an electrode material, the electrode is not significantly damaged even if, for example, a continuous flow of about one to two cycles occurs.

Metals such as copper-tungsten sintered alloy and molybdenum have arc-extinguishing properties like brass. Further, the carbon electrode is capable of discharging at a low voltage and has a small variation in the operation start voltage. It also has arc-extinguishing properties only for weak current circuits. When a conductive ceramic electrode is used, heat resistance hardly causes a problem, but it is possible to improve the arc extinguishing property by devising a material.

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] September 19, 1999 (September 9, 1999
9)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Detailed description of the invention

[Correction method] Change

[Correction contents]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

When a spark discharge gap is used as a lightning arrester, there is some delay in operation, but since the voltage between the electrodes during discharge is low, even if a large current flows, the power consumption between the spark electrodes is reduced in the case of a shock voltage. Since the electrode is relatively small, the electrode is slightly consumed, so that it has a feature that the electrode can sufficiently withstand an excessively large impact large current.

In a lightning arrester for a composite low-voltage circuit as proposed in Japanese Patent No. 2628736, even when a semiconductor lightning arrester and a spark discharge gap are connected in parallel, both operations can be coordinated, so that both responsiveness and surge withstand capability are improved. An excellent low-voltage surge arrester can be obtained. Therefore, the problem of the operation delay of the spark discharge gap can be solved.

However, when used in a power supply circuit, when an excessive lightning surge arrives and the spark gap operates, a current from the power supply voltage may continuously flow due to a low discharge voltage between the electrodes. . This current is called a continuous flow, and in the case of a continuous flow, unlike a shock current, the current flows continuously, so that the electrode is greatly consumed. The present invention is proposed for the purpose of preventing such follow-up current, preventing the spark electrode from being worn, and further improving the performance of the combined type lightning arrester for low voltage circuit.

[0005]

[Industrial applications]

[0006] The present invention relates to a structure of a spark gap, in which even if a strong lightning surge enters, a spark flow does not cause a wake in the spark gap and the spark gap is not damaged by the wake.

[0007]

[Prior art]

[0008] The spark gap currently used in the compound type low voltage lightning surge arrester is shown in FIG.
A pair of square brass rods 1 and 1a are used facing each other. In this case, the discharge starts on the outer periphery of the facing surface, and the spark tends to spread along the outer periphery line. For this reason,
Since the arc due to the discharge is on the outer periphery of the electrode, the cooling effect by the electrode surface cannot be expected. Further, although a part of the arc enters the gap between the electrodes, the effect that the arc is diffused on the electrode surface is poor because the gap between the electrodes is narrow and parallel.

[0009]

[Problems to be solved by the invention]

That is, in order to prevent the follow-up current, the current is concentrated as much as possible on the electrode surface portions (anode point and cathode point) of the arc to increase the voltage drop between the electrodes, and the arc is diffused or cooled. The purpose is to prevent ionization of air between the electrodes.
Accordingly, it is an object of the present invention to obtain an electrode structure capable of preventing a downstream flow.

Further, in order to prevent the electrode from being worn, it is necessary to select an electrode material. Generally, a brass electrode is used, but an electrode using a copper-tungsten sintered alloy, molybdenum, carbon, a conductive ceramic, or the like can be used to further reduce damage to the electrode due to electric discharge.

[0012]

[Means for Solving the Problems]

[0013] In order to prevent the continuation of current, the arc at the time of discharge starts around the outer periphery of the counter electrode and does not run along the outer periphery. As you run, the arc that ran further inside,
The electrode structure needs to be diffused along the internal electrode surface and cooled between them.

(1) In the spark discharge gap in which a pair of electrodes are opposed to each other, the opposed surfaces are slightly inclined left and right from the position of the vertical center line of each opposed surface. Spark discharge gap. (2) In a spark discharge gap in which a pair of electrodes are opposed to each other, a spark discharge gap is characterized in that the opposed surfaces are sloped downward from the location of the center line beside each opposed surface, not vertically. . And so on.

[0015] Also, as an electrode material, based on experience from the past,
We proposed brass, copper-tungsten sintered alloy, molybdenum, carbon, conductive ceramic, etc.

[0016]

[Operation]

Regarding the movement of the arc at the time of discharge in the spark discharge gap of the present invention, for example, as shown in FIG. Explain that the discharge starts at one of the upper and lower ends on the vertical center line, and the arc foot (cathode point, anode point) travels along the vertical center line and penetrates into the gap between the opposing electrodes. Since the wall is fan-shaped from the center to the left and right, the arc legs 21, 21a
The (cathode point, anode point) also moves from the center line of the electrode to the left and right surfaces, and current concentrates there, so that the potential drop increases, and the entire arc (22) is sandwiched between the electrodes and receives a cooling action. Since diffusion is performed while preventing ionization (thermal ionization), the formation of a new cathode point (the previous anode point) is also prevented, and the subsequent flow is interrupted.

[0018]

【Example】

FIG. 3 shows an embodiment relating to a vertical square rod electrode spark gap of the present invention. Metal electrodes 3, 3a of a spark gap main body 3 are press-fitted into metal electrode tubes 31, 31a. , 31a from outside the push screw 32, 3
2a.

The metal tubes 31, 31a are provided with screw rods 33, 33a for lead wires.

The metal electrodes 30, 30a pressed against the metal electrode tubes 31, 31a are opposed to each other with a small gap m.

Further, it is mounted and fixed to mounting bases 35 made of porcelain having a concave portion 34 at the center by mounting screws 36 and 36a.

FIG. 4 relates to a horizontal square bar electrode spark gap 4 with a gap m according to the present invention. 40 and 40a are spark electrodes,
From the location of the horizontal center line, the opposing surface is vertically inclined slightly downward.

[0024]

【The invention's effect】

According to the spark discharge gap of the present invention, the outer periphery of the discharge gap does not become a main discharge point as in the prior art, but the discharge starts almost at the center of the opposite electrode surface, as described above. , The anode point) moves from the center of the electrode to the outside on the electrode surface that spreads in a fan shape, so that the cooling and diffusion action is promoted by the electrode surfaces on both sides, and ionization between the electrodes is prevented, Subsequent flow from the power source is unlikely to occur.

Even if a follow-up current of about one or two cycles occurs, the current concentrates on the electrode surface, and the voltage drop at that part also becomes large. Therefore, a new cathode point (the conventional anode point) Is blocked and the following flow is cut off.

In the AC 100 V to 200 V circuit, the vertical flow or the horizontal type brass square rod electrode extinguishes the arc, but in the circuit of 200 V AC or more, it is also considered that about 1 to 2 cycles of the arc flow are generated. Since a sintered material of copper-tungsten, molybdenum, carbon, conductive ceramic, or the like is used as an electrode material, the electrode is not significantly damaged even if, for example, a continuous flow of about one to two cycles occurs.

Metals such as copper-tungsten sintered alloy and molybdenum have arc-extinguishing properties like brass. Further, the carbon electrode is capable of discharging at a low voltage and has a small variation in the operation start voltage. It also has arc-extinguishing properties only for weak current circuits. When a conductive ceramic electrode is used, heat resistance hardly causes a problem, but it is possible to improve the arc extinguishing property by devising a material.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of the drawings]

FIG. 1 shows a conventional spark gap.

FIG. 2 is a view showing the principle of the vertical square rod electrode spark gap of the present invention.

FIG. 3 is a perspective view of a vertical square rod electrode spark gap according to the present invention, in which a metal electrode tube is mounted on the outer periphery of an electrode, and a pair of electrodes pressed against each other are arranged to face each other.

FIG. 4 is a horizontal square bar electrode spark gap showing another embodiment of the present invention.

DESCRIPTION OF THE SYMBOLS 1, square bar electrode spark gaps 2, 3, vertical square bar electrode spark gap 4 of the present invention, horizontal square bar electrode spark gap 20, 20a 30, 30a of the present invention vertical square bar electrode 21, 21a Arc foot (cathode point, anode point) 22 Arc 31, 31a Metal electrode tube 32, 32a Push screw 33, 33a Screw rod 34 Recess 35 Mounting base 36, 36a Mounting screw 40, 40a Horizontal square rod electrode m Spark gap

Claims (7)

[Claims] 1. A spark discharge gap in which a pair of electrodes are opposed to each other, wherein the opposed surfaces are inclined slightly downward left and right from the position of the vertical center line of each opposed surface. . 2. A spark discharge gap in which a pair of electrodes are opposed to each other, characterized in that the opposed surfaces have a slight downward and upward slope from the center line beside each opposed surface. . 3. A spark discharge gap using a brass electrode as the electrode according to claim 1.2. 4. A spark discharge gap according to claim 1.2, wherein the electrode is made of a sintered copper tungsten alloy. 5. The spark discharge gap according to claim 1.2, wherein molybdenum is used for the electrode. 6. The spark discharge gap according to claim 1.2, wherein carbon is used for the electrode. 7. A spark discharge gap according to claim 1.2, wherein said electrode is made of a conductive ceramic.