JPS61227387A - Surge absorption element and manufacture thereof - 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 [Field of Industrial Application] The present invention relates to a structure for absorbing surge current applied to a surge absorbing element by discharging.

[Conventional technology]

A conventional surge absorbing element is, for example, disclosed in Japanese Utility Model Application No. 57-2218.
As described in Publication No. 6, a thin conductive film (carbon film) is formed on the outer surface of a cylindrical insulator, cap-shaped electrodes are fitted on both ends, lead wires are connected, and the conductive film is thinned in the middle. An annular discharge section is formed by cutting into an annular shape, and the whole is enclosed in a glass covering material filled with gas, so that a surge current is discharged at the annular cut section. When manufacturing this type of insulator, it takes time and effort to form a conductive film on the entire surface of each cylindrical insulator, fit electrodes on both ends, and cut the discharge part into an annular shape. Since the discharge occurs between the electrolytic coatings, there is a problem in that an excessive current flows during discharge. Furthermore, since the discharge occurs around the entire circumference of the annular cut portion of the opposing conductive coatings, the discharge is unevenly distributed over the entire area, and furthermore, since the discharge portion is a thin metal film, there is a problem that wear and tear during discharge is severe.

[Problem that the invention seeks to solve]

In view of the above-mentioned problems, the present invention enables Inuyama production by making it possible to form electrodes and resistive films by printing without making elements one by one, and prevents excessive current from flowing during discharge, and also prevents damage caused by discharge. The aim is to reduce the amount of discharge and ensure uniform discharge.

[Means for solving problems]

In the present invention, a resistive film is formed between a pair of electrodes formed on an insulating unit substrate, both ends of which are connected to the electrode, the resistive film is separated in the middle, and a small amount of discharge is generated from each of the separated resistive films. By protruding a plurality of discharge parts having pointed tips facing each other with gaps in between, a resistive film is interposed between the electrodes to prevent excessive current from flowing, and furthermore, the resistive film separated in the middle By making the discharge portions having a plurality of sharp ends protrude relative to each other, discharge is made uniform and accurate. In addition, the manufacturing method includes a process of printing and forming a pair of electrodes on each of a large number of unit boards of an insulating board made up of a collection of insulating unit boards, and a process of forming a pair of electrodes by printing a discharge interval in the middle between each pair of electrodes. This process involves printing the film and dividing the insulating substrate on which the large number of electrodes and resistance films are printed into the required number of unit boards, so a large number of electrodes and resistance films are formed at once by printing. The aim is to enable production.

[Effect]

According to the present invention, electrodes and a resistive film are formed in large quantities and with uniform thickness on an insulating substrate by printing, and the discharge portion is also formed at the same time as printing the resistive film. Furthermore, the resistive film formed between the electrodes prevents excessive current from flowing during discharge. In addition, a plurality of opposed sharp tip portions are formed in the discharge portion of the resistive film, so that the discharge is uniform and accurately performed.

〔Example〕

Example 1 An example of the present invention will be described with reference to the manufacturing process diagrams shown in FIGS. 1 to 9.

a. A pair of electrodes 3, 3 made of Pa-Ag glaze paste are printed and baked for each unit substrate 1 on a ceramic flat insulating substrate 2 consisting of an assembly of a large number of unit substrates 1. (Fig. 1) 68 Next, resistor Il made of Ru-Ag glaze paste between electrodes 3.3! 4 is printed and baked, and both ends are electrodes 3.
, 3 are partially overlapped and connected. (The resistive film 4 may be made of TaN or TiN.) At this time, the longitudinal center portion of the resistive film 4 is spaced apart, and a plurality of discharge portions having sharp tip portions 5 are formed facing each other from the separated ends. 6 are formed in a sawtooth shape, and a small discharge gap 7 is interposed between the distal end portions 5, 5 of the opposing discharge portions 6, 6. The formation of the discharge portions 6, 6 is also printed at the same time as the resistor WA4.

(Figure 2 shows a plan view, and Figure 3 shows a longitudinal cross-sectional view) C1 Next, the insulating substrate 2 is divided into unit substrates 1.

(FIG. 4 shows a plan view, and FIG. 5 shows a vertical cross-sectional view.) 60 Next, lead wires 8, 8 are connected to the electrodes 3, 3.

(FIG. 6 shows a plan view, and FIG. 7 shows a vertical cross-sectional view.) e. The element piece 9 obtained as described above is sealed in a glass insulating cover 10, and a gas such as argon gas is Product A
t7. (FIG. 8 shows a plan view, and FIG. 9 shows a vertical cross-sectional view.) The obtained product A is an electrode 3 formed on a unit insulating substrate 1.
, 3, there is a resistive film 4 connected at both ends to the electrodes 3, 3.
is formed, and a plurality of sawtooth-shaped discharge portions 6, 6 are provided in the middle of the resistive film 4, spaced apart across the width direction, and protrude from the left and right resistive films 4°4. A small discharge gap 7 is interposed between the sharp tip portions 5, 5. Furthermore, lead wires 8.8 are connected to the electrodes 3, 3 to form an element piece 9, and this element piece 9 is enclosed in an insulating cover 10 filled with gas.

Next, the operation of the above embodiment will be explained.

When a surge voltage is applied between the electrodes 3, 3, a discharge occurs between the mutually opposing sharp tips 5, 5 of the plurality of discharge portions 6.6 in the discharge gap 7 of the resistive film 4.
, 4 is discharged evenly and reliably in the width direction. Moreover, since the resistive film 4 is formed between the electrodes 3, 3, it functions in the same way as resistors connected in series, and prevents excessive current from flowing during discharge. In addition, if the resistive film 4 is made of metal glaze, printing becomes possible and the film becomes thicker, making it suitable for large current M currents.If the film thickness is made thinner by using TaN, TiN, etc., it becomes suitable for micro currents. Accuracy can be increased.

Example 2 This will be explained with reference to FIG. Discharge portions 6, 6 of resistive film 4
Conductive films 11 and 11 are respectively formed thereon. The conductive film 11.11 is also formed with a serrated sharp tip 12.12 having the same shape as the resistance skin g14.

The formation of the conductive film 11.11 makes the discharge more reliable.

The other structures and operations are the same as in the first embodiment.

Example 3 This will be explained with reference to FIG. Electrode 1 on the back side of unit substrate 1
3.13 and a resistive film 14 are formed, and the electrode 3 on the front surface and the electrode 13 on the back surface are connected with a conductive film 15 such as solder.

In this embodiment, the resistance mechanism on the back side is connected in parallel to the element piece 9 on the front side.

Note that the other configurations and operations are the same as in the first embodiment.

Example 4 This will be explained with reference to FIG. Two element pieces 9°9 are electrically connected. Therefore, during manufacturing, the insulating substrate 2
When dividing, two unit substrates 1 each having an electrode 3 and a resistive film 4 formed thereon are divided into one composite substrate 18, and two electrodes at one end are connected to form one electrode 16 as a lead l!
It can be easily manufactured by connecting 11.

As shown in the above embodiments, the element piece 9 on which the surge function part is formed on the front surface can exhibit various functions by adding other functions to the back surface or by making the unit substrates 1 continuous. .

Next, Figure 13 shows resistance skin 11! Cut J4 and discharge part 6
This is an explanatory diagram for forming a kerf 19 by first cutting the resistive film 4 in a lightning bolt shape as shown in figure a with a laser beam, and then cutting it in a reverse lightning shape as shown in figure b to form a groove 20. By forming this, the sharp tip portion 5 of the discharge portion and the discharge portion gap 7 can be formed.

(Effects of the Invention) According to the present invention, a resistive film is formed between a pair of electrodes formed on an insulating unit substrate, with both ends connected to the electrode,
This resistive film is separated in the middle, and a plurality of discharge parts each having a logarithmic sharp tip are provided protruding from the separated resistive film through a small discharge gap. Since a discharge is generated, a uniform discharge can be generated between the left and right resistive films. Also, since the discharge part is not metal, there is less wear and tear on the coating. Furthermore, since a resistive film is interposed between the electrodes, excessive current can be prevented from flowing during discharge.

In addition, during manufacturing, there is a process of printing and forming a pair of electrodes on each of a large number of unit boards of an insulating board made of a collection of insulating unit boards, and a process of forming a resistive film by separating a discharge interval between each pair of electrodes. A large number of electrodes and resistance films are formed on the insulating substrate at once by printing. It is suitable for Inuyama production, and since the resistor film v1 is formed by printing, the discharge gap can be formed at the same time as printing, which saves the effort of forming the discharge gap by cutting after forming the resistor film. The shape of the discharge portion can be accurately formed into any shape suitable for discharge. Furthermore, since the insulating substrate is made up of a large number of unit substrates, it is possible to divide the insulating substrate into the required number of unit substrates to continuously obtain 2 or 3 WA element pieces.

[Brief explanation of drawings]

1 to 9 are explanatory diagrams of the manufacturing process of a surge absorbing element showing one embodiment of the present invention, FIGS. 10 and 11 are front views showing another embodiment of the present invention, and FIG. 12 is a further FIGS. 13a and 13b are longitudinal sectional plan views showing another embodiment, and are diagrams showing the process of cutting the resistive film. 2. Unit substrate, 3. Electrode, 4. Resistive film, 5. Sharp tip, 6. Discharge portion, 7. Discharge gap.

Claims (2)

[Claims] (1) A resistive film is formed between a pair of electrodes formed on an insulating unit substrate, with both ends connected to this electrode, and the resistive film is separated in the middle, and a small amount of discharge is generated from each separated resistive film. A surge absorbing element characterized by having a plurality of protruding discharge parts each having a sharp tip disposed opposite to each other with a gap therebetween. (2) A step of printing and forming a pair of electrodes on each of a large number of unit boards of an insulating board made up of a collection of insulating unit boards, and printing and forming a resistive film with a discharge interval separated midway between each pair of electrodes. and dividing the insulating substrate on which the large number of electrodes and resistive films are printed into the required number of unit substrates.