JP3520763B2 - Manufacturing method of chip type surge absorber - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a chip type surge absorber used to protect various devices from surges and prevent accidents.

[0002]

2. Description of the Related Art Conventionally, as a chip type surge absorber, as shown in FIG. 3, discharge electrodes 21A and 21B and terminal electrodes 22A and 22B are printed on one plate surface of an alumina substrate 21 and discharged in the atmosphere. However, in such a chip type surge absorber, the discharge start voltage is affected by atmospheric pressure, humidity, and dust because the discharge electrode and the insulating part for ensuring insulation are exposed to the atmosphere. It has the drawback of not being stable.

As a solution to this problem, as shown in FIG. 4, a pair of discharge electrodes 31A, 31 are provided with a discharge gap.
An alumina substrate 31 having B formed on the plate surface, an alumina substrate 32 having an opening 32A for forming a discharge chamber formed at the center of the plate, and an alumina substrate 33 having no holes (FIG. 4A) In order, a surge absorber body 34 is laminated and integrated by using a glass paste (FIG. 4B), and terminal electrodes 35A and 35B are formed on both end faces thereof (FIG. 4B).
(C)).

In this chip type surge absorber, the discharge gaps of the discharge electrodes 31A and 31B are arranged so as to face the opening 32A, and the opening 32A becomes a closed discharge chamber.

Further, a cylindrical rib material made of glass is placed on the alumina substrate on which the discharge electrodes are formed, and a glass sheet having a low softening point is placed on the rib material, and the rib material is integrated by heating to form a portion of the rib material. There is also a chip type surge absorber in which a discharge chamber is formed.

[0006]

A chip type surge absorber having a discharge chamber solves the problems of atmospheric pressure, humidity, dust, etc., and provides a chip type surge absorber having a stable discharge starting voltage. The manufacturing process has the following drawbacks.

(I) As shown in FIG. 4, when the three alumina substrates are laminated and integrated, or when the alumina substrate and the rib material are integrated by using a glass sheet, the positional displacement of the substrates easily occurs. In addition to the large variation in product dimensions, in the case of significant variation, it becomes impossible to seal the gas filled in the discharge chamber.

(Ii) When using a glass or glass sheet for fusion containing a binder, it is necessary to perform binder removal processing, but when this binder removal processing is incomplete, good sealing cannot be performed. There is.

In order to solve such a problem, the present applicant forms an electrode on a substrate and forms a wall for a discharge chamber by depositing glass powder on the electrode by an electrodeposition method, A patent application was previously filed for a method of manufacturing a chip type surge absorber having a discharge space by stacking this substrate on a substrate on which a discharge electrode and a terminal electrode are formed (Japanese Patent Application No. 10-45311), but the electrodeposition method is There is a problem that the operation is frequent and it is difficult to control the concentration of the electrodeposition liquid.

The present invention solves the above-mentioned conventional problems and is a chip type surge absorber having a discharge chamber in a sealed gas atmosphere, which does not require binder removal processing for sealing and prevents variations in product dimensions. An object of the present invention is to provide a method for manufacturing a chip type surge absorber that can be easily sealed.

[0011]

A method of manufacturing a chip type surge absorber according to the present invention has a glass tube whose both ends are sealed with an insulating substrate and which is filled with a sealed gas atmosphere. A chip type sir having a pair of discharge electrodes formed on a plate surface through a discharge gap facing the glass tube.
A method of manufacturing a disorber, the method comprising:
Insulating substrate on one side and recess for accommodating plate and glass tube
With a work hole having a step portion capable of accommodating
Heater, and the other side of the carbon heater
Put the edging substrate, then the other insulating substrate in this recess
Place the glass tube on top, and then place one on top of the step and the glass tube.
By placing the other insulating substrate, the carbon heater
Insulating board, glass tube, and insulation
After storing the flexible substrate, the gas inside the glass tube is replaced with the enclosed gas.
Then, by firing, the glass tube and both insulating substrates
It is characterized by joining and integrating .

According to the present invention, two insulating substrates and a glass tube are prepared, a discharge electrode is formed on one of the insulating substrates in advance, and the both ends of the glass tube whose inside is replaced with a filling gas are used. Chip type surge absorber only by joining the insulating substrate
It can be easily manufactured.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 (a) is a perspective view showing an embodiment of a chip type surge absorber manufactured according to the present invention, and FIG. 1 (b) is a sectional view taken along the line BB of FIG. 1 (a). It is sectional drawing which follows the line.

This chip type surge absorber 1 comprises a glass tube 4 whose both ends are sealed by alumina substrates 2 and 3 and whose inside is filled with a sealed gas atmosphere. The discharge electrodes 5A, 5B are formed through a discharge gap provided so as to face the discharge chamber 6 surrounded by the glass tube 4. 7A and 7B are continuous with the discharge electrodes 5A and 5B, respectively, on both end surfaces of the alumina substrate 3,
It is a terminal electrode formed on the edge side of the surface opposite to the surface on which the discharge electrodes 5A and 5B are formed.

The plate surface of the alumina substrate 2 is a square whose one side is approximately the same size as the outer diameter of the glass tube 4. Hereinafter, the alumina substrate 2 may be referred to as a “sealing side alumina substrate”, and the alumina substrate 3 on which the discharge electrodes 5A and 5B are formed may be referred to as a “discharge side alumina substrate”.

Next, the tip type surge absorber 1 will be described .
The manufacturing method will be described with reference to FIG. 2 (a) ~ (f) .

First, the sealing side alumina substrate 2 and the glass tube 4
A carbon heater 10 having a work hole 11 having a concave portion 11A capable of accommodating a discharge hole and a step portion 11B capable of accommodating the discharge side alumina substrate 3 is used.
The alumina substrate 2 on the sealing side is put in the concave portion 11A of the
(A), (b)). Then, the glass tube 4 is placed on the sealing side alumina substrate 2 in the recess 11A (FIG. 1 (c),
(D)). The recess 11A has the same shape in plan view as the plate surface of the sealing-side alumina substrate 2, and the length of one side thereof is also substantially the same dimension. The depth of the recess 11A is the same as the thickness of the sealing-side alumina substrate 2. Since the height of the glass tube 4 is almost equal to the total height of the glass tube 4, the alumina substrate 2 on the sealing side and the glass tube 4 are not
1A, and the upper end surface of the glass tube 4 is stepped 1
1B or the end face of the glass tube is slightly protruding.

Next, the discharge side alumina substrate 3 is placed on the stepped portion 11B of the carbon heater 10 and the glass tube 4 (see FIG. 1).
(E), (f)). The stepped portion 11B has the same shape in plan view as the discharge side alumina substrate 3, and the length of one side thereof is also substantially the same size, and the depth thereof is slightly deeper than the thickness of the discharge side alumina substrate 3, and therefore the discharge side The alumina substrate 3 is completely contained in this step 11B.

After the sealing side alumina substrate 2, the glass tube 4 and the discharge side alumina substrate 3 are housed in the work hole 11 of the carbon heater 10 in this manner, the gas in the glass tube 4 is replaced with the enclosed gas. By firing at a high temperature of about 600 to 800 ° C., the glass tube 4 and both alumina substrates 2 and 3 are joined and integrated.

By using the carbon heater 10 in which such a work hole 11 is formed and forming a discharge electrode at a predetermined position on one of the alumina substrates in advance, the alumina substrates 2 and 3 and the glass tube 4 are separated. Alignment becomes easier,
To manufacture a chip type surge absorber 1 in which a sealed discharge chamber 6 facing a discharge gap between discharge electrodes 5A and 5B is formed between alumina substrates 2 and 3 and a glass tube 4 based on good workability. You can

The discharge electrode 5 of the discharge side alumina substrate 3
A, 5B and the terminal electrodes 7A, 7B can be formed by a conventional method by printing and firing a conductive paste.
The discharge electrodes 5A, 5B and the terminal electrodes 7A, 7B are generally formed to have a thickness of about 1 to 100 μm.
The discharge gaps of A and 5B are set to about 0.005 to 0.5 mm depending on the required discharge characteristics. Although Ag is generally used as the conductive material of the conductive paste, other materials such as Ag-Pt and Ti may be used.

The enclosed gas is He, N ₂ , A
One of r, Ne, Xe, SF ₆ , CO ₂ , H _{2 and the} like can be used alone or in combination of two or more.
In addition, the pressure of the enclosed gas is usually 100 to 1
It is set to about 000 Torr.

Although an alumina substrate is used as the insulating substrate in the description of FIGS. 1 and 2, an insulating substrate other than the alumina substrate may be used. As this insulating substrate, normally, 2.0 to 3.2 mm × 1.25 mm on the discharge electrode side.
.About.1.6 mm × 0.5 to 1.5 mm thickness is used, and 1.0 to 2.0 mm × 1.
A size of 0 to 2.0 mm × 0.5 to 1.5 mm is used. As the glass tube, one having an outer diameter equal to the length of one side of the insulating substrate on the sealing side and having a thickness of 0.1 to 0.5 mm and a length of 0.5 to 1.0 mm is used. To be done.

[0025]

EXAMPLES The present invention will be described more specifically with reference to Examples and Comparative Examples below.

Example 1 In accordance with the method shown in FIGS. 2 (a) to 2 (f), FIG.
The chip type surge absorber shown in (b) was manufactured.

The outer diameter of the glass tube 4 is 1.5 m.
m, thickness 0.15 mm, and length 1 mm were used. Moreover, as the sealing side alumina substrate 2, 1.5 mm × 1.5
The thickness of the discharge side alumina substrate 3 was 1.6 mm × 3.2 mm × 0.5 mm, and the thickness of the discharge side alumina substrate 3 was 1.6 mm × 3.2 mm × 0.5 mm. Ag on the discharge side alumina substrate 3
The paste has a width of 0.1 mm through a discharge gap of 0.1 mm.
mm discharge electrodes (thickness 10 μm) 5A, 5B were formed and terminal electrodes (thickness 10 μm) 7A, 7B were formed.

After inserting the sealing side alumina substrate 2, the glass tube 4 and the discharge side alumina substrate 3 into the work hole 11 of the carbon heater 10, the gas inside the glass tube 4 is changed to Ar gas (200
Torr), and baked at 800 ° C. to integrate the alumina substrates 2 and 3 and the glass tube 4.

The discharge characteristics of the chip-type surge absorber 1 thus obtained and variations in external dimensions were examined, and the results are shown in Table 1. The discharge start voltage was obtained by applying a DC voltage and determining the voltage at the time when the discharge current reached 1 mA.

Comparative Example 1 In Example 1, a chip type surge absorber having no discharge chamber as shown in FIG. 3 was formed by using only the alumina substrate on which the terminal electrodes and the discharge electrodes were formed. The discharge characteristics of the surge absorber and variations in outer dimensions were examined, and the results are shown in Table 1.

Comparative Example 2 A chip type surge absorber was manufactured by the method shown in FIGS.

An alumina substrate having discharge electrodes of the same dimensions as in Example 1, an alumina substrate having a hole with a diameter of 1 mm in the center of the plate, and a flat alumina substrate (the dimensions of the alumina substrate are 1.6 mm × 3.2mm x 0.5mm thickness)
, A glass paste containing a binder is printed on the plate surface, the binder is removed at 400 ° C., the atmosphere in the discharge chamber is replaced with Ar gas (200 Torr), and the mixture is fired at 800 ° C. to be laminated and integrated. By forming terminal electrodes, a chip type surge absorber was obtained.

Regarding this chip type surge absorber,
In the same manner as in Example 1, the discharge characteristics and variations in external dimensions were examined, and the results are shown in Table 1.

[0034]

[Table 1]

[0035]

As described in detail above, according to the method of manufacturing a chip type surge absorber of the present invention, a chip type surge absorber having a discharge chamber in a filled gas atmosphere can be easily manufactured without the need for binder removal processing. And it can be manufactured efficiently. Therefore, according to the present invention, it is possible to manufacture a high-quality chip type surge absorber having a stable discharge starting voltage with a high yield.

[Brief description of drawings]

FIG. 1 (a) is a perspective view showing an embodiment of a chip type surge absorber manufactured according to the present invention, and FIG. 1 (b) is a cross section taken along line BB of FIG. 1 (a). It is a figure.

[Figure 2] manufacturing method of a chip type surge absorber of the present invention
3 is a schematic cross-sectional view illustrating the embodiment of FIG.

FIG. 3 is a perspective view showing a conventional chip type surge absorber.

FIG. 4 is a perspective view showing a conventional chip type surge absorber.

[Explanation of symbols]

1 chip type surge absorber 2-3 alumina substrates 4 glass tubes 5A, 5B discharge electrode 6 discharge chamber 7A, 7B terminal electrode

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-7-245878 (JP, A) JP-A-62-283583 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01T 4/10 H01T 4/12

Claims (5)

(57) [Claims] 1. A glass tube, both ends of which are sealed with an insulating substrate and the inside of which is a sealed gas atmosphere, and a pair of insulating substrates are provided on a plate surface of the insulating substrate with a discharge gap facing the glass tube. Chip type surge absorber with discharge electrode
A method for manufacturing the same, comprising: a concave portion capable of accommodating the other insulating substrate and the glass tube;
Work hole having a step part that can accommodate the other insulating substrate
Using the formed carbon heater , put the other insulating substrate in the recess of this carbon heater,
Next, place the glass tube on the other insulating substrate in the recess.
It can, then, put one of the insulating substrate in the step portion and the glass tube
This allows the insulation of the other inside the work hole of the carbon heater.
Flexible substrate, glass tube and one insulating substrate
By replacing the gas in the lath tube with the fill gas and firing
A method of manufacturing a chip type surge absorber , characterized in that a glass tube and both insulating substrates are joined and integrated . 2. The recess of the carbon heater according to claim 1.
Part has the same shape in plan view as the plate surface of the other insulating substrate
The length of one side is almost the same, and the depth of the recess is
The total of the thickness of the other insulating substrate and the height of the glass tube is approximately
The insulating substrate and glass tube on the other
The upper end surface of the glass tube is flush with the step.
The end surface of the glass tube is slightly protruding.
Manufacturing method of chip type surge absorber characterized by
Law. 3. The carbon heater according to claim 1 or 2.
The step part of the switch has the same shape in plan view as one insulating substrate.
The length of one side is almost the same, and the depth of one side is
A little deeper than the thickness of the insulating substrate, one insulating substrate is
A chip characterized by being completely contained in this step
Type surge absorber manufacturing method. 4. The odor according to any one of claims 1 to 3.
The other insulating board has a glass tube with a side length of
The square shape is approximately the same size as the outer diameter of
Method of manufacturing up-type surge absorber. 5. The insulating substrate according to claim 4,
2.0-3.2 mm x 1.25-1.6 mm x 0.5-
It has a thickness of 1.5 mm and the other insulating substrate
Plate is 1.0 to 2.0 mm x 1.0 to 2.0 mm x 0.5
~ 1.5 mm thick, outside the glass tube
The diameter is equal to the length of one side of the other insulating substrate, and the thickness is 0.
1-0.5 mm, length 0.5-1.0 mm
A method of manufacturing a characteristic chip type surge absorber.