JP2001135454A - Surge absorber and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surge absorber and its manufacturing method easy in assembling the absorber in which positioning of a surge absorber element in a tube can be made precisely. SOLUTION: A surge absorbing element 15 comprising an electro-conductive membrane 30 that has a discharge trigger gap 31 on the surface of an insulator 20 and terminal electrodes 23, 23 installed at the terminals of the membrane is housed in a tube 40 filled with inert gas, and terminals of the tube 40 are sealed with sealing electrodes 50, 50, and the sealing electrodes 50, 50 are connected to the terminal electrodes 23, 23, and thus the surge absorber 10 is constructed. The terminal electrodes 23, 23 and the sealing electrodes 50, 50 are connected integrally by welding. The terminal electrodes 23, 23 are provided with projections 25 for welding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surge absorber having a surge absorbing element sealed in a tube and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, there is a risk that a surge current due to lightning or the like may enter an electronic device and destroy it. For this reason, a surge absorber is attached to release the surge current by discharging, thereby protecting the electronic device.

In this surge absorber, as shown in FIG. 5, a surge absorbing element 100 is housed in a glass tube 110 filled with an inert gas, and both ends of the tube 110 are sealed with sealing electrodes 12.
0, 120 and sealing electrodes 120, 120
Terminal electrodes 1 attached to both ends of surge absorbing element 100
08, 108.

The surge absorbing element 100 is a rod-shaped insulator 1
01, a conductive film 103 is formed on the surface thereof, and a discharge trigger gap 105 for dividing the conductive film 103 in the center thereof.
And cap-shaped terminal electrodes 108, 1 at both ends.
08 is attached.

[0005] When a surge current is applied between the lead terminals 121 attached to the sealing electrodes 120, 120, a discharge is first generated in the discharge trigger gap 105, and the insulation in the tube 110 is destroyed. 10
Discharge starts between 8,108.

By the way, as shown in FIG. 6, a method of manufacturing the surge absorber is as follows. A glass tube 110 is inserted into a concave portion 61 of a carbon heater 60, and a lead terminal 1 is previously inserted therein.
21 is inserted in this order, the other sealing electrode 120 to which the surge absorbing element 100 and the lead terminal 121 are attached, and the surrounding atmosphere is evacuated and then inert. By introducing gas and heating the carbon heater 60, the glass tube 110 is sealed with the sealing electrode 12.
This is carried out by welding and sealing the outer periphery of 0,120.

[0007] However, when the surge absorber is assembled by the above method, the four parts are connected to the carbon heater 6.
Since it is necessary to assemble them into the recesses 61 of 0, the work is complicated and the assembling time becomes longer.

On the other hand, in the above-described assembling method, the surge absorbing element 100 cannot be positioned in the glass tube 110 when the surge absorbing element 100 is inserted into the concave portion 61, so that the surge absorbing element 100 is not necessarily located at the center of the glass tube 110, but is located in the glass tube 110. In many cases, the glass tube 110 is sealed while being moved to one side or tilted and in contact with the inner wall of the glass tube 110. When the terminal electrode 108 comes into contact with the inner wall of the glass tube 110, the glass tube 110 is damaged when the surge is absorbed. Therefore, the glass tube is broken when a surge current is repeatedly applied. was there.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to provide a surge absorber which is easy to assemble and can accurately position a surge absorbing element in a pipe, and a method of manufacturing the same. Is to provide.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a surge absorbing element comprising a conductive film having a discharge trigger gap formed on the surface of an insulator and a terminal electrode provided at an end thereof. Is housed in a tube filled with an inert gas, the end of the tube is sealed with a sealing electrode, and the sealing electrode is connected to the terminal electrode. It was configured to be connected and integrated by welding. Here, it is preferable that a projection for welding is provided on at least one of the opposing surfaces of the terminal electrode and the sealing electrode. Further, the present invention provides a surge absorbing element having a conductive film having a discharge trigger gap formed on a surface of an insulator and a terminal electrode provided at an end thereof, a pipe for housing the surge absorbing element, and an end of the pipe. A sealing electrode for sealing the portion is prepared, a sealing electrode is connected and fixed in advance to a terminal electrode of the surge absorbing element, and then the tube is provided around the surge absorbing element to which the sealing electrode is connected and fixed. Then, the surge absorbing element covered with the tube was heated to seal between the tube and the sealing electrode.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view showing a surge absorber 10 according to the present invention. As shown in the figure, the surge absorber 10 has a conductive film 30 formed on a surface (peripheral surface) of an insulator 20 made of a cylindrical ceramic body, and a discharge trigger gap 31 for dividing the conductive film 30 is provided. A pair of cap-shaped terminal electrodes 23, 23 are attached to both ends of the insulator 20 to constitute the surge absorbing element 15, and the surge absorbing element 15 is made of a glass tube filled with an inert gas such as argon gas. The tube 40 is housed, and both ends of the tube 40 are sealed with sealing electrodes 50, 50. At this time, the sealing electrodes 50, 50 are connected to the terminal electrodes 23, 23.

Here, the sealing electrodes 50, 50 are formed of a dumet wire which is a special metal (copper-coated iron-nickel alloy wire) having a high degree of adhesion to glass. The terminal electrodes 23 are made of, for example, stainless steel.

In the present invention, the terminal electrodes 23,
Both end surfaces of the sealing electrode 50 are integrally connected to both end surfaces of the sealing electrodes 50 by welding. Particularly in this embodiment,
At the center of both end surfaces of the terminal electrodes 23, 23, welding projections 25 projecting outward (toward the sealing electrodes 50, 50).
25 is provided so that the welding energy is concentrated on the projections 25 and 25 and the welding is reliably performed on the sealing electrodes 50 and 50.

Next, a method of manufacturing the surge absorber 10 will be described. First, as shown in FIG. 2, sealing electrodes 50, 50 are previously connected to both ends of the terminal electrodes 23, 23 of the surge absorbing element 15 formed by press-fitting the terminal electrodes 23, 23 to both ends of the insulator 20 by welding. Fix it. Sealing electrode 5
Lead terminals 55, 55 are previously attached to the center of the outer sides of 0, 50 by spot welding.

The surge absorbing element 15 and the sealing electrodes 50, 50
The welding between them can be performed by a normal welding machine (not shown). At this time, the surge absorbing element 15 and the sealing electrodes 50 and 50 are welded.
Can be welded in a state where both are securely held on the jig, so that the surge absorbing element 15 can be reliably welded to the central portions of the sealing electrodes 50, 50. This welding is usually performed automatically and continuously by a welding machine.

In this embodiment, in particular, since the projections 25 are provided on both terminal electrodes 23, the energy at the time of welding is concentrated on this portion, and the surge absorbing element 15
Is more accurately and reliably welded to the central portions of the sealing electrodes 50, 50.

Next, as shown in FIG.
The tube 40 and the surge absorbing element 15 to which the sealing electrodes 50 and 50 are attached are housed in the concave portion 61 of FIG. 0, the lid 65 is closed as shown in FIG. An inert gas such as a gas is introduced, and the carbon heater 60 is heated in the atmosphere for a predetermined time (for example, 700
° C). As a result, the tube 40 softens and contracts, and the sealing electrode 5
0 and 50 are welded, the both ends of the tube 40 are sealed, the surge absorbing element 15 is completely shut off from the outside and hermetically sealed, and the surge absorber 15 shown in FIG. 1 is completed.

In the present invention, the surge absorbing element 1
5 is welded to the center of the sealing electrodes 50, 50,
At the time of assembling parts into the concave portion 61 of the carbon heater 60, the surge absorbing element 15 does not tilt in the tube 40 or the center axis does not become eccentric from the center axis of the tube 40.
It is not possible for the contact to occur.

Therefore, even if a surge current is repeatedly applied to the surge absorbing element 15, the tube 40 will not be damaged, and the surge life can be improved.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications may be made within the scope of the claims and the technical idea described in the specification and the drawings. Deformation is possible. It should be noted that any shape or material not directly described in the specification and the drawings is within the scope of the technical idea of the present invention as long as the effects and effects of the present invention are exhibited.

For example, in the above embodiment, the terminal electrodes 23, 2
3, the projections 25, 25 for welding are provided. Alternatively, the projections 25, 25 may be provided on the sealing electrodes 50, 50 side. The projections 25 may be provided on both. Further, the protrusion 25 does not necessarily need to be provided at the center position of the terminal electrode 23 or the sealing electrode 50, and may be provided at another position or a plurality of protrusions may be provided. In short, it may be provided on at least one of the opposing surfaces of the terminal electrodes 23, 23 and the sealing electrodes 50, 50.

[0022]

As described in detail above, the present invention has the following excellent effects. Since the terminal electrode and the sealing electrode are connected and integrated by welding, positioning in the pipe when the surge absorbing element is inserted into the pipe can be performed accurately, and therefore, the surge absorbing element does not tilt in the pipe. It cannot happen that the terminal electrode or the like contacts the tube. Therefore, even if the surge current is repeatedly applied to the surge absorbing element, the tube is not damaged and the surge withstand amount (withstand current) is not reduced, and the surge life can be improved.

Since the terminal electrode and the sealing electrode are connected and integrated by welding, the number of parts at the time of assembling the parts into the carbon heater is limited to the two parts of the surge absorbing element with the sealing electrode and the tube. Thus, the assembling is easy, the assembling time is shortened, and the mass production can be simplified.

In particular, when a projection for welding is provided on at least one of the opposing surfaces of the terminal electrode and the sealing electrode, the surge absorbing element can be more accurately and reliably welded to the central portion of the sealing electrode.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a surge absorber 10 according to the present invention.

FIG. 2 is a diagram illustrating a method of manufacturing the surge absorber 10;

FIG. 3 is a view showing a method of manufacturing the surge absorber 10;

FIG. 4 is a diagram illustrating a method of manufacturing the surge absorber 10.

FIG. 5 is a view showing a conventional surge absorber.

FIG. 6 is a diagram illustrating a method for manufacturing a conventional surge absorber.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Surge absorber 15 Surge absorption element 20 Insulator 23 Terminal electrode 25 Projection 30 Conductive film 31 Discharge trigger gap 40 Tube 50 Sealing electrode 55 Lead terminal 60 Carbon heater

Claims (3)

[Claims] 1. A surge absorbing element comprising a conductive film having a discharge trigger gap formed on a surface of an insulator and a terminal electrode provided at an end thereof is accommodated in a tube filled with an inert gas. A surge absorber having an end sealed with a sealing electrode and connecting the sealing electrode to a terminal electrode, wherein the terminal electrode and the sealing electrode are integrally connected by welding. Absorber. 2. The surge absorber according to claim 1, wherein a projection for welding is provided on at least one of the opposing surfaces of the terminal electrode and the sealing electrode. 3. A surge absorbing element comprising: a conductive film having a discharge trigger gap formed on a surface of an insulator; and a terminal electrode provided at an end thereof; a tube for accommodating the surge absorbing element; A sealing electrode for sealing the portion, and a sealing electrode is connected and fixed in advance to a terminal electrode of the surge absorbing element, and then the tube is provided around the surge absorbing element to which the sealing electrode is connected and fixed. And heating the surge absorbing element covered with the tube to seal the space between the tube and the sealing electrode.