JP2900505B2 - Surge absorbing element - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a multi-pole tube surge absorbing element. In particular, the present invention relates to a triode or multi-pole surge absorbing element in which discharge initiation voltages between a desired number of terminals are all equal.

[Problems to be Solved by Conventional Techniques and Inventions] Conventionally, three- or multi-terminal surge absorbing elements include:
A gap type surge absorbing element such as a three-terminal arrester is used. However, this gap type surge absorbing element
Due to the length of the internal gap connected to each terminal due to its shape, there is a drawback that it is impossible to make all the firing voltages between the terminals equal.

That is, in the conventional technology, the discharge starting voltage between the two outer terminals of the surge absorber becomes approximately equal to the discharge starting voltage between the central and outer terminals due to the length of the distance between the terminals of the surge absorber caused by the shape factor. It had the disadvantage of being twice as large.

In this specification, the term “micro gap” refers to “a minute gap that divides a conductive thin film formed on the surface of a cylindrical insulator made of ceramic, and is usually formed through such a micro gap. A device having a function of absorbing a surge in which a conductive thin film divided into a plurality of layers is provided on the surface of a cylindrical insulator made of ceramic is called a microgap device, and cap-shaped electrodes are provided at both ends of the cylindrical insulator. A lead wire is attached to the electrode, and the whole is covered and insulated by an insulating jacket (sealing glass tube) such as glass, and an inert gas such as nitrogen gas is contained in the inner space of the jacket. Even if an electric field is applied to the lead wires at both ends, when the voltage is low, the micro gap does not conduct due to the micro gap, and when a voltage exceeding a certain level is applied, discharge starts between the micro gaps and The gas is ionized for the continuation of the discharge to form an arc discharge, and an overvoltage / overcurrent surge can flow to absorb the surge. It is used to protect these devices from destruction without causing surges to enter circuits such as electronic devices, and to prevent accidents.

In the present invention, in order to solve the above-described problems, a micro-gap is formed between the terminals even at these portions having different distances between the terminals, and the discharge starting voltage is controlled, so that the discharge between all the terminals is performed. An object of the present invention is to provide a surge absorbing element having the same starting voltage. Another object of the present invention is to provide a product having improved impulse discharge initiation characteristics by using a micro gap.

Means for Solving the Problems Here, the gist of the present invention is a conductive thin film formed on the surface of an insulating cylindrical body (1) having electrodes (7) at both upper and lower ends. (2) Inside micro gap (3)
And an insulating cylindrical body (4) provided concentrically and with an appropriate space around the cylindrical body (1) of the microgap element,
The cylindrical body (4) has a desired number of conductors (6) at equal intervals.
And a conductive thin film (2 ') is provided on the outer surface of the cylindrical body (4) in each of the divided regions, and the conductive thin film (2) in each of the divided regions is provided. ′)
Is provided with a microgap (3) at substantially the center thereof, and encloses the microgap element and an insulating cylinder (4) divided by the conductor (6), and a desired number of conductors ( 6) having an enclosed glass tube having an outer portion provided on the outer side, the number of each of the electric conductors (6) being equal to the number of each of the electrodynamic members provided at equal intervals, with the outer portion and the electrodes (7) at both ends being electrodes. This is a multi-terminal surge absorbing element having a number of electrode terminals. Further, according to the present invention, a micro gap (3) is formed in a conductive thin film (2) formed on the surface of an insulating cylindrical body (1) having electrodes (7) at both upper and lower ends. A gap element and an insulating cylinder (4) provided concentrically and with an appropriate space around a cylindrical body (1) of the microgap element. A conductor (6) is provided in the middle in the direction, the cylinder (4) is divided into two, and a conductive thin film (2 ') is formed on the outer surface of the cylinder (4) in each of the two divided regions. ), And the conductive thin film (2 ') in the two regions
Is provided with a microgap (3) at substantially the center thereof, and encloses the microgap element and an insulating cylinder (4) divided by the conductor (6). A three-terminal surge absorbing element, characterized in that it has a sealed glass tube provided with an outer part on the outside, and has an outer part of the conductor (6) and electrodes (7) at both ends as electrode terminals, and a three-electrode terminal. I will provide a.

[Operation] According to the present invention, a cylindrical element having a conductive film having a microgap in a portion having a different distance between terminal electrodes and a similar cylindrical element installed concentrically with the cylindrical element are connected and combined, and By enclosing in a tube,
By controlling the change in the discharge starting voltage caused by the difference in the distance between the terminal electrodes, the discharge starting voltage between all the terminals is made equal.

That is, in the conventional technology, three surge absorbing elements
When two terminal electrodes are provided, the distance between the outer two terminal electrodes differs from the distance between the center and the outer terminal electrodes due to the shape factor. Was about twice the firing voltage between the central and outer terminal electrodes.

On the other hand, in the present invention, by connecting a cylindrical or cylindrical element having a conductive coating surface with a microgap formed between terminals having different distances between the electrodes,
Discharge starts at the micro gap of the conductive film,
The characteristic of forming a main discharge between the terminal electrodes and the discharge starting voltage are determined by the micro gap of the conductive film. It is possible to make the firing voltage between all the terminal electrodes equal.

Furthermore, by using a microgap of a conductive film formed on the surface of the insulating cylindrical body, the impulse discharge starting voltage is improved.

Glass, fired ceramics, organic substances, and the like can be used as the cylindrical insulating material used in the present invention. Further, it is preferable to use a glass or ceramic envelope for enclosing these elements.

As the conductive film formed on the surface of the cylindrical body, a film obtained by sputtering a metal such as TiN, various nitrides, carbides, or BaAl is preferable. The microgap can be formed by cutting this film with a laser.

In addition, a metal material such as stainless steel, Fe, an iron-nickel alloy, or a Ni—Cr—Fe alloy can be used as an electrode of the microgap element.

Next, the multi-terminal surge absorbing element of the present invention will be described with reference to specific examples, but the present invention is not limited to the description.

Example The structure of the surge absorbing element of the present invention is shown in the sectional view of FIG. That is, an 11 mm long alumina insulator (cylindrical) sealed with argon gas 9 in a lead glass cylindrical exterior body 8
1. A conductive film 2 made of TiN is formed on the outer surface and an end surface of a cylindrical alumina insulator 4 having a length of 5.5 mm on the surface of the substrate 1. As described above, one micro gap 3 was formed. A hemispherical stainless steel cap 5 is joined to both ends of the cylindrical insulator 1 having a conductive film having a macro gap 3 on each surface, and further, as shown in FIG. On the other hand, a cylindrical insulator 4 is installed outside the concentric circle, and a central electrode 6 is provided at the center of the cylindrical insulator 4 so as to penetrate from the glass exterior body 8 to the cylindrical insulator 4 as shown in the figure. Further, at both ends of the glass exterior body 8, outer electrodes 7 are provided and sealed.

The conventional product has, for example, a structure as shown in the cross-sectional view of FIG. 2, and encloses a structure provided with a central terminal electrode 11 almost in the middle between the outer terminal electrodes 10 with an insulating outer case 12, It is filled with an inert gas 13 therein.

On the other hand, when a single gap is used in the surge absorbing element of the present invention, the discharge start voltage and the impulse discharge start voltage between the terminals in the present embodiment are shown together with the conventional product for comparison. , Are shown in Table 1.

As can be seen from Table 1, in the prior art, the firing voltage between the outer terminals is about twice the firing voltage between the center and the outer terminals. On the other hand, according to the present invention, the discharge starting voltage between the terminal electrodes 6-7 and 7-7 is:
Became equal.

Further, as shown in Table 1, it was confirmed that the impulse discharge starting voltage was reduced by using the micro gap.

[Effects of the Invention] In the multi-terminal surge absorbing element of the present invention, first, by forming a micro gap between the terminal electrodes, it is possible to equalize the firing voltage even in a portion where the distance between the terminals is different. It is a thing.

Second, in particular, a three-terminal type surge absorbing element having the same discharge starting voltage between the three terminals has been provided, and technical effects such as being provided.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the structure of the surge absorbing element of the present invention. FIG. 2 is a sectional view showing a conventional surge absorbing element. [Description of Signs of Main Parts] 1 ... Cylindrical alumina insulator 2,2 '... Conductive film 3 ... Insulating groove or micro gap 4 ... Outer cylindrical alumina insulator 5 ... Cab 6 ... Central terminal Electrode 7: Outer terminal electrode 8: Insulating sheath or glass tube 9: Argon gas

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takaaki Ito 2270 Yokoze, Yokoze-cho, Chichibu-gun, Saitama Pref. Ceramics Laboratory, Mitsubishi Mining Cement Co., Ltd. Sho 62-64987 (JP, U) Shokai Sho 55-14212 (JP, U) Shosho 58-43790 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01T 1 / 00-4/20

Claims (2)

(57) [Claims] A conductive thin film (2) formed on the surface of an insulating cylindrical body (1) having electrodes (7) at both upper and lower ends.
A micro-gap element having a micro-gap (3) formed therein, and an insulating cylinder (4) provided concentrically and with an appropriate space around a cylindrical body (1) of the micro-gap element. The cylinder (4) is provided with a desired number of conductors (6) at equal intervals, divided by the conductor (6), and divided into cylinders (4) in respective divided regions. A conductive thin film (2 ') is provided on the outer surface, and the conductive thin film (2') in each region is provided with a microgap (3) substantially at the center thereof. An insulating glass body (4) divided by the body (6) is sealed, and a sealed glass tube provided with an outer portion of a desired number of conductors (6) on the outside is provided. And the number of terminals of the electromotive bodies provided at equal intervals and the number of terminals of 2 using the electrodes (7) at both ends as electrodes Multi-terminal surge absorber characterized by having an electrode terminal. 2. A conductive thin film (2) formed on the surface of an insulating cylindrical body (1) having electrodes (7) at both upper and lower ends.
A micro-gap element having a micro-gap (3) formed therein, and an insulating cylinder (4) provided concentrically and with an appropriate space around a cylindrical body (1) of the micro-gap element. A conductor (6) is provided in the middle of the cylindrical body (4) in the vertical direction, and the cylindrical body (4) is
The conductive thin film (2 ') is provided on the outer surface of the cylindrical body (4) in each of the two divided areas.
The micro-gap (3) is provided substantially in the center of the conductive thin film (2 ') in one region, and the insulating cylinder (4) divided by the micro-gap element and the conductor (6) And a sealed glass tube in which the outer portion of the conductor (6) is provided on the outside, the outer portion of the conductor (6) and the electrodes (7) at both ends are used as electrode terminals, and three electrode terminals are provided. A three-terminal surge absorbing element, characterized in that: