JPH03214580A - Micro-gap type surge absorbing element - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a micro-gap type surge absorption element, and in particular, to a method for producing a micro-gap type surge absorption element, which improves characteristics by changing the gas sealing method compared to conventional products. be. [Prior art] The conventional micro-gap type surge absorption element was
As shown in No. 3-57918, a conductive ceramic thin film is attached to the surface of an insulator, the conductive thin film is divided into a plurality of parts, and a metal or alloy with high electrical conductivity is coated on both ends of the conductive ceramic thin film. After fixing and forming electrodes, lead wires are attached to the electrodes by welding. Dumet lines are used as node lines. Since glass is used as the insulating coating material for airtightness to seal gas between the electrodes, Dumet wire is used as the glass-filled wire. That is, in the prior art, as shown in FIG. 2, lead wires are welded to the electrodes at both ends, and glass is sealed to the lead wires to maintain airtightness. As mentioned above, the conventional technology maintains airtightness by sealing the lead wire and glass. However, one of the surge protection characteristics is increased surge resistance. This surge resistance characteristic indicates how much surge energy the surge absorption element can withstand. One way to increase this surge resistance is to increase the space inside the glass. In this case, the conventional technology has the disadvantage that the larger the diameter of the glass, the more difficult it becomes to process the glass, and at the same time, the influence of heat such as distortion on the glass increases. [Problems to be Solved by the Invention] The present invention provides a micro-gap type surge absorbing element that aims to increase the surge resistance without significantly affecting the heat on glass unlike the prior art. The purpose is to [Structure of the Invention] [Means for Solving the Problems] The present invention provides a ceramic element in which a conductive thin film having a micro gap is formed on the surface of a cylindrical ceramic insulator, and a cylindrical ceramic insulator is provided at both ends of the ceramic element. A camp electrode having an inner diameter approximately the same as the outer diameter of the recess, a brim-shaped portion larger than that diameter, and a camp electrode having a structure in which the outer periphery of the brim is bent to an appropriate width is mechanically press-fitted or pressure-welded, and the bending is performed. This is a micro-gap type surge absorbing element f which has a structure in which a certain amount of gas is confined around the microphone I1 gap by rolling a cylindrical insulating exterior body that is slightly larger than the outer circumferential diameter of the part and a bent part. A micro-gap type surge absorbing element having a structure in which a lead wire of an appropriate diameter is attached to the cab/cab electrode part of the -7 microgap type surge absorbing element having a buckwheat-shaped camp electrode is suitable. Further, a micro-gap type surge absorbing element using a brim-shaped cap electrode having a structure having a lead portion of an appropriate width and length from a part of the brim-shaped cap electrode is suitable. [Function] According to the present invention, the shape of the electrodes in both chambers of the microgap conductive thin film is slightly smaller than the diameter of the ceramic cylindrical insulator, and when it is compressed to the Je edge body, it is difficult to fix the microgap conductive thin film with the insulator. It has a four-gun part that maintains sufficient strength, and a brim-like structure that is larger than its diameter, and the outer peripheral part of the brim structure has a part that is bent to an appropriate width. The feature is that it uses a cap electrode. Therefore, the diameter of the cap electrode with the brim-like structure is slightly smaller than the diameter of the insulating exterior body used for gas sealing, and the bent part of the outer periphery of the cap electrode with the brim-like structure and the It is designed to thermally seal the insulating exterior body and maintain gas tightness. A microgap type surge absorption element generates an initial discharge in a minute microgap area, and furthermore, when the energy of the surge is large, the discharge in the microgap area becomes a double discharge that transitions to an arc discharge between electrodes. It is characterized by having a relaxation mechanism. For this reason, while retaining the fast response characteristics of the microgap, in response to large surges, the device shifts to an interelectrode opening, resulting in less damage to the microgap element. However, because the area of the electrode was small, arcing occurred on the surface of the conductive thin film, and therefore the damage to the conductive thin film caused by the arc discharge was considerable. In the micro-gap type surge absorbing element of the present invention, since a flange-like structure is used as the cap 1l electrode, the area of the electrode is significantly larger than that of the conventional technology. This makes it possible to disperse the current density of the arc furnace and keep it away from the surface of the conductive thin film. In other words, the present invention makes it possible to reduce damage to the conductive coating during arc discharge and increase surge resistance by using a cap electrode with a brim-like structure. Next, the microgap type surge absorbing element of the present invention will be explained using specific examples, but the present invention is not limited by the explanation. [Example 1] This example is shown in Figures 1A and B. As shown in Figure 1A, diameter 1.7mΦ, length 5.5
A TiN thin film 22 is deposited on the entire surface of the cylindrical mullite element 21 by sputtering, and then a flange-shaped film with an inner diameter of 1.681111 mm and an outer diameter of 10.0 Φ is formed on both ends of the mullite element 21. After mechanically enlarging the cap electrodes 24a and 24b made of Kovar metal, a YAG laser is used to spread the TiNM film 22 formed on the surface of the mullite element 21 to a width of about 30 μm in the circumferential direction. The inner diameter 10.5 Φ, the outer diameter 12.5 Φ, and the length g 6.01 are cut with 1 microgap (23).
Using a No. 111 cylindrical lead glass 25, the outer periphery of the cap electrodes 24a, 24b having a collar-like structure made of Fvar metal and both ends of the cylindrical lead glass 25 are heated by high frequency heating in an argon gas atmosphere. The micro gap 23 is sealed with argon gas 27 around the micro gap 23. The state of sealing between the bent outer peripheral portion of the cap electrode 24a having a brim-like structure and the cylindrical lead glass 25 is retracted as shown in FIG. 1B. Table 1 shows the results of measuring and comparing the surge resistance of the product manufactured according to this example and the product manufactured using the conventional technique. In addition, the surge resistance is measured by JE
Measurement was performed using a current surge of (8 x 20) microseconds as specified in C-212 (Tekki Gakkai, Electrical Standards Committee Standard). As shown in Table 1, in the conventional technology, the surge withstand capacity was limited to about 3000A, but the surge absorption element of the present invention can easily withstand up to 400OA. Table 1 Conventional product A 1 raw seedling Example 1 1 ceramic body Mullite Mullite Mullite film
TiN TiN TiN node wire diameter 0.411m 0.6 ■Main body outer cover diameter
6,0■ 6,0■ Body outer cover length 21.0■
2l,0■Surge resistance 1500A 300
0A firing starting voltage 300V 300V [Example 2] This example is shown in Fig. 3A and B. As shown in Figure 3A, first, diameter 1.7cm x length 5.5mm
The entire surface of the mullite element 31 of No. 111 is coated with SnO. A thin film 32 is deposited and the mullite element 31
At both ends, the inner diameter is 1.681111, and the outer diameter is 12.
．． After mechanically press-fitting and fixing cap electrodes 34a and 34b made of 42 alloy with a brim-like structure of 0.0 mm, YA
Using a G laser, the S n O .5 cabinets, outer diameter 14.5 cabinets, length 6.0
Using the cylindrical lead glass 35 of (3), the cap-like structure cap electrode 3 is heated by high frequency heating in an atmosphere of Ar gas 37.
The cylindrical lead glass 35 is sealed around the outer peripheries of the 4a and 34b, and the periphery of the micro gap 33 is sealed with Ar gas 37. The state of enclosing between the bent outer peripheral portion of the cap electrode 34a having a brim-like structure and the cylindrical ship glass 35 is retracted as shown in FIG. 3B. Furthermore, a solder-plated mild steel wire 38 with a diameter of 0.5 cm is electrically welded and attached as a lead wire 38 to the center of the electrode portion 34a of the gas-sealed main body. Table 2 shows the comparison results of the surge resistance of the device manufactured by this example and the device manufactured by the conventional technology. Note that the surge resistance was measured in the same manner as in Example 1.

As shown in this example, the surge resistance of Example 1 can be increased to 400 by increasing the diameter of the rib-shaped structure key electrode.
It is possible to obtain a surge withstand capacity of 5000A, which is even greater than that of OA. Table 2 Conventional product C
S n O t S n O * S
n O *Node wire diameter 0.4111 0
．． 6ml O. 5-Main body outer cover diameter 5,Qm
6.0 ■ 14.5 ■ Body outer cover length 21.0
■ 21.0 ■ 6. Olll surge resistance
1500A 3000A 5000A Discharge start tolerance 300V 300V 300V [
Example 3] Figure 4 shows this example. As shown in Figure 4, the diameter is 1.7aox, the length is 5.51
, S is applied to the entire surface of the lie 1 and element 41 using a spraying method.
nO. A thin film 42 is deposited and SU is applied to both ends of the mullite element.
After mechanically compressing and fixing S-kiss A and knobs 43a and b, Y
Using an AG laser, the SnQ. The thin film 42 is canted in the circumferential direction with a width of about 50 μm, and the micro gap 44 is
After the final formation, cap electrodes 45a with a flange-like structure made of 42 alloy having an inner diameter slightly larger than the outer diameter of the SUS caps are attached to both ends of the SUS caps 43a and 43b.
A cylindrical lead glass 46 having an inner diameter slightly larger than the outer diameter of the flange-shaped cap electrode is installed on the outside of the b-shaped cap electrode, and using high frequency heating in an Ar gas 47 atmosphere,
The cylindrical lead glass 46 is connected to the brim-like structured cap electrode 45.
Sealing the bent outer peripheral portions 48a and 48b of a and b,
In this case, At gas is sealed around the micro gap 44. Table 3 shows the comparison results of the surge resistance of the device manufactured by this example and the device manufactured by the conventional technique.

Incidentally, the measurement of Cern resistance was carried out in the same manner as in Example 1.
As shown in this example, in the conventional technology, the limit of the load bearing resistance was about 3000A, but in the sash absorbing element of the present invention, as in Example 1, the load resistance can easily be 4000A.
It is possible to withstand up to A. Spoon E 1 Saramai Violet 1 Example 3 Ceramic body Mullite Mullite Mullite film
S n O * S n O t Lead wire diameter 0.4■ 0. 6111 Main body outer cover diameter
6.0 ■ 6.0 ■ Body outer cover length 21.0 ■
21.0■Surge resistance 1500A 3000
A release start voltage 300V 300V [Example 4] Figure 5 shows this example. As shown in FIG. 5, SnO.
A thin film 52 is deposited, and SUS caps 53a. After fixing b mechanically, the SnO thin film 52 was cut in the circumferential direction to a width of about 50 μm using a YAG laser to form one microphone [I gap 54]. .5 ■ 4000A 300v SnO. After that, the SUS caps 53a, b and the mullite element 51 having the micro gap 54, an inner diameter of 10.5 Φ,
Cylindrical lead glass 56 with outer diameter 12.5mm and length 6.01mm
A cap electrode 55@,b with a flange-like structure made of 42 alloy designed to mechanically press the mullite element 51 and the cylindrical lead glass 56 is pressed against both ends of the mullite element 51 and the cylindrical lead glass 56, and a high-frequency wave is applied in an Ar gas atmosphere. Using heating, the end surfaces 58a, b of the cylindrical lead glass 56 and the outer periphery of the brim-shaped structure cap electrode are sealed, and the periphery of the micro gap 54 is sealed with Ar gas 57. In this embodiment, the end face of the cylindrical lead glass 56 is covered with the brim-shaped cap electrode 55aXb, thereby preventing mechanical damage to the cylindrical lead glass 56. Table 4 shows the comparison results of the surge resistance of the product manufactured by this example and the product manufactured by the conventional technology. The surge resistance was measured in the same manner as in Example 1.
As shown in this example, in the conventional technology, the surge withstand capacity is
Although the limit was about 3000A, the surge absorbing element of the present invention can easily withstand up to 4000A as in Example 1. Table 4 Conventional product A Conventional product BIu ``Ceramic body Mullite Mullite Mullite film
S n O * S n O * Lead wire diameter Q, 4m 0.6■Main body outer cover diameter 6.
0+111 6.0 Garden body outer cover length 21. 0
m21. 0■Surge resistance 1500A
3000A discharge starting pressure 300V 300
V [Effects of the Invention] The microgap surge absorbing element of the present invention has a brim-shaped arc discharge portion larger than the diameter of the insulating ceramic element, and furthermore, the outer peripheral portion of the brim-like structure has an appropriate width. Microgap type SnO. using a cap electrode with a bent structure. 12.5 ■ 6.5 ■ It is a 4000A 300v surge absorption element, and for this reason, firstly, it is possible to increase the area of the arc discharge part compared to the conventional technology, and therefore, the arc discharge By dispersing the current density and moving it away from the surface of the conductive film, we were able to provide a micro-gap type surge absorption element with increased surge resistance. Secondly, the outer peripheral part of the electrode with a brim-like structure is bent to an appropriate width, and this part is used to seal it with an insulating covering material such as glass, making it possible to confine a certain amount of gas inside, To provide a micro-gap type surge absorbing element which makes it possible to easily enlarge the internal space of the surge absorbing element without causing thermal effects such as distortion on an insulating covering material, as compared to conventional ones. Therefore, the present invention makes it possible to increase the surge withstand capacity without impairing the double discharge mechanism of the conventional micro-gap type surge absorption element, and significantly improves its characteristics. Remarkable technical effects were obtained.

[Brief explanation of drawings]

FIGS. 1A and 1B are a cross-sectional view showing the structure of the micro-gap type surge absorbing element of the present invention, and a perspective view showing the structure of the brim-like structure electrode. Figure 2 is a cross-sectional view of a conventional micro-gap surge absorption element. FIG. 3A%B is a cross-sectional view showing the structure of another example of the micro-gap type surge absorbing element of the present invention, and a perspective view showing the structure of the brim-like structured electrode therefor. 4 and 5 are cross-sectional views showing the structure of other examples of the micro-gap type surge absorbing element of the present invention. [Explanation of symbols of main parts 21, 31, 4 1. ．． ．． ．． ．． ．． ．． ．． Mullite element 2
2, 3 2. ．． ．． ．． ．． ．． ．． ．． T i N thin film or S n
Oz thin film 23, 33, 4 3. ．． ．． ．． ．． ．． ．． Micro gap 24a, b, 31a, b, 45a, b, 5
5a,b. ．． ．． ．． ．． ．． ．． ．． Buckwheat cap electrode 2 5
, 3 5, 4 6, 5 6. ．． ．． ．． ．． ．． ．． Lead glass 3 6 a5 b. ．． ．． ．． ．． ．． ．． Solder plated mild steel wire

Claims (1)

[Claims] 1. At both ends of a cylindrical ceramic insulator element having a conductive thin film with a micro gap formed on its surface, a recess with an inner diameter approximately the same as the outer diameter of the cylindrical ceramic element, and a recess with an inner diameter that is larger than the outer diameter of the cylindrical ceramic insulator element. A large, brim-shaped part, and furthermore,
A cap electrode having a structure in which the outer periphery of the brim portion is bent to an appropriate width is mechanically press-fitted or pressed into contact with each other, and an insulating exterior body is provided with a diameter slightly larger than the diameter of the outer periphery of the bent structure of the cap electrode. A micro-gap type surge absorption element having a structure in which a certain amount of gas is sealed around the cylindrical ceramic insulator having the micro-gap by sealing the insulating exterior body and the outer peripheral portion of the folded structure. 2. The micro-gap surge absorbing element according to claim 1, having a structure in which a lead wire of an appropriate diameter is attached to the cap electrode portion of the brim-like structure. 3. The microgap type surge absorbing element according to claim 1, further comprising a lead portion having an appropriate width and length from a part of the cap electrode having the brim-like structure.