JP5891829B2 - Surge absorber and manufacturing method thereof - Google Patents

Description

  The present invention relates to a surge absorber used for protecting various devices from surges caused by lightning strikes and preventing accidents, and a method for manufacturing the same.

  Portions where electronic devices for communication equipment such as telephones, facsimiles, modems, etc. are connected to communication lines, power lines, antennas, CRT drive circuits, etc. A surge absorber is connected to prevent damage due to thermal damage or ignition of an electronic device or a printed circuit board on which the device is mounted due to an abnormal voltage.

  Conventionally, for example, as shown in Patent Document 1, a pair of terminal electrode members arranged opposite to each other, and an insulating tube that seals the discharge control gas inside by arranging the pair of terminal electrode members at both ends, A surge absorber is formed on the inner surface of the pair of terminal electrode members, and a bulge electrode material having a raised central portion is formed, and the bulge electrode material includes a metal having a higher electron emission capacity than the terminal electrode member. Proposed. In this surge absorber, the electric field concentrates on the raised central portion of the bulged electrode material and can be easily discharged, and can withstand a surge having a long wave tail. Further, since the bulging electrode material contains a metal having a higher electron emission capability than the terminal electrode member, it is not necessary to apply a discharge aid, and the discharge start voltage is stabilized.

  Further, in Patent Document 2, an insulating tube surrounding a discharge space is fixed between a pair of terminal electrode members by brazing, and the inner surface of the pair of terminal electrode members faces the other terminal electrode member. A surge absorber has been proposed in which protruding protruding electrodes are fixed, and concave portions are formed on the protruding electrodes as brazing material stopper means for restricting the rising of the molten brazing material to the discharge start surface.

  In this surge absorber, the brazing material that is in a molten state at the time of brazing tends to scoop up the surface of the terminal electrode member and adhere to the discharge start surface at the tip, and the material as the electrode member is changed to the brazing material. Therefore, the discharge start voltage is prevented from changing. That is, in this surge absorber, even when the molten brazing material reaches the base end portion of the protruding electrode during brazing, the creeping up to the discharge starting surface is regulated by the concave portion of the brazing material stopper means. It itself can be maintained as an electrode member.

JP 2010-170917 A JP 2007-329029 A

The following problems remain in the conventional technology.
That is, in the conventional structure, it is necessary to reduce the discharge gap when the distance between the electrodes is shortened to produce a discharge start voltage having a low voltage. However, in the technique of Patent Document 1, the surge absorber itself Therefore, there is a disadvantage that the discharge capacity is reduced and the surge resistance is reduced. There is also a method of shortening the distance between electrodes by forming a discharge electrode to form a protruding electrode provided with protrusions. In this method, however, the molten brazing material crawls up unevenly on the surface of the protruding electrode and discharges. The starting voltage could change. On the other hand, in the technique of Patent Document 2, a concave portion is formed on the outer surface of the protruding electrode as brazing material stopper means for restricting the rising of the molten brazing material, but in this case, the protruding electrode is configured. When the electron emission ability of the material is low, in order to improve the discharge characteristics, it is necessary to separately apply an electron emitting agent to the tip of the electrode, which causes a problem that the manufacturing process and the manufacturing cost increase.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a surge absorber having a stable low discharge start voltage and capable of being manufactured at low cost, and a method for manufacturing the same.

  The present invention employs the following configuration in order to solve the above problems. That is, the surge absorber according to the first invention includes an insulating tube, a pair of sealing electrodes that closes both ends of the insulating tube and seals the discharge control gas therein, and the pair of sealing members. A protruding electrode member having a base end fixed to one of the electrodes with a conductive adhesive and a tip protruding toward the other, the protruding electrode member having a groove or a hole formed from the base end to the tip. The conductive fusing material contains a metal having a higher electron emission capacity than the sealing electrode, and extends from the proximal end to the distal end in the groove or the hole.

  In this surge absorber, the conductive fusing material contains a metal having a higher electron emission capacity than the sealing electrode, and is formed in the groove or hole formed from the base end to the tip end of the protruding electrode member from the base end to the tip end. Because it extends, the conductive fusing material with high electron emission ability reaches the tip of the protruding electrode member that becomes the discharge start surface, and it is stable without the need to apply an electron emitting agent. A low discharge start voltage. That is, in the technique of the above-mentioned Patent Document 2, the brazing material that has crawled up in the middle of the protruding electrode is regulated so that the brazing material does not become a discharge start surface. Since the high conductive fusion material is positively extended to the tip of the protruding electrode member, it is possible to start discharge at a low voltage stably from the tip of the protruding electrode member.

The surge absorber according to a second aspect of the present invention is characterized in that, in the first aspect, a reservoir of the conductive fusion material is formed at the tip of the protruding electrode member.
That is, in this surge absorber, since the reservoir portion of the conductive fusing material is formed at the tip of the protruding electrode member, the metal having high electron emission ability is present at the tip, so that the stability can be further reduced. Discharge can be started with voltage.

A surge absorber according to a third invention is characterized in that, in the first or second invention, the protruding electrode member is a cylindrical member in which a through hole is formed as the hole.
That is, in this surge absorber, since the protruding electrode member is a cylindrical member having a through hole formed therein as a hole portion, the conductive melt extending into the through hole of the cylindrical member and reaching the tip is provided. It can be discharged by the deposit.

A surge absorber according to a fourth invention is characterized in that, in the first or second invention, the protruding electrode member is a column member in which the groove is formed on a side surface.
That is, in this surge absorber, since the protruding electrode member is a column member having a groove formed on the side surface, it can be discharged by the conductive fusion material extending into the groove and reaching the tip.

A surge absorber according to a fifth invention is characterized in that, in the first or second invention, the protruding electrode member is a metal plate member in which a gap is formed by bending a plate material.
That is, in this surge absorber, the protruding electrode member is a metal plate member in which a plate-like material is bent to form a gap-like groove, so that the conductive material extends into the gap-like groove of the plate and reaches the tip. It can be discharged by a fusing material.

A surge absorber according to a sixth invention is the surge absorber according to any one of the first to fifth inventions, wherein the protruding electrode member is formed of Cu, and the conductive fusion material is a brazing material containing Ag. It is characterized by.
That is, in this surge absorber, the protruding electrode member is made of Cu, and the conductive fusing material is a brazing material containing Ag. Therefore, the brazing material containing Ag having an electron emission ability higher than that of Cu is used. It can be discharged, and a low and stable low discharge start voltage can be obtained.

  A method for manufacturing a surge absorber according to a seventh invention is a method for manufacturing a surge absorber according to any one of the first to sixth inventions, wherein a discharge control gas and a protruding electrode member are placed inside. An assembly process of closing both end openings of the insulating tube with a pair of sealing electrodes, and the pair of sealing electrodes and the insulating tube with a conductive fusion material provided on the inner surfaces of the pair of sealing electrodes. And a fixing step of fixing one of the pair of sealing electrodes and the base end of the protruding electrode member, and the protruding electrode member has a groove or a hole formed from the base end to the tip. The conductive fusion material contains a metal having a higher electron emission capacity than the sealing electrode, and the conductive fusion material heated and melted in the fixing step is formed in the groove or by the capillary phenomenon. Inside the hole from the base end to the tip end of the protruding electrode member Field to be characterized be extended.

  That is, in this surge absorber manufacturing method, in the adhering step, the conductive fusion material heated and melted extends from the proximal end to the distal end of the protruding electrode member in the groove portion or the hole portion by capillary action. Before the process, there is no need to separately prepare a protruding electrode member provided with a conductive fusion material in the groove or hole, and the conductive fusion material is extended to the tip of the protruding electrode member at the same time in the fixing process. Can do. Therefore, it is possible to reduce the manufacturing process and the manufacturing cost.

According to an eighth aspect of the present invention, there is provided the surge absorber manufacturing method according to the seventh aspect, wherein the groove or the hole is formed by a path that is the shortest distance from the base end to the tip end of the protruding electrode member. Features.
That is, in this surge absorber manufacturing method, the groove or hole is formed by a path that is the shortest distance from the proximal end to the distal end of the protruding electrode member. Due to the phenomenon, it is possible to crawl up to the tip at the shortest distance, and the conductive adhesive can be reliably extended from the base end to the tip.

The present invention has the following effects.
That is, according to the surge absorber and the manufacturing method thereof according to the present invention, the conductive fusion material contains a metal having a higher electron emission capacity than the sealing electrode, and is formed from the base end to the tip end of the protruding electrode member. Since it extends from the proximal end to the distal end in the groove or hole, there is no need to apply an electron emitting agent, and a stable low discharge start voltage can be obtained.
Therefore, the discharge start voltage can be lowered and the response speed can be increased, and the device can be manufactured at low cost.

It is the perspective view (a) which shows 1st Embodiment of the surge absorber which concerns on this invention, and its manufacturing method, an exploded perspective view (b), and the longitudinal cross-sectional view (c) cut | disconnected in front of the protruding electrode member. It is the perspective view (a) which shows 2nd Embodiment of the surge absorber which concerns on this invention, and its manufacturing method, an exploded perspective view (b), and the longitudinal cross-sectional view (c) cut | disconnected in front of the protruding electrode member. It is the perspective view (a) which shows 3rd Embodiment of the surge absorber which concerns on this invention, and its manufacturing method, an exploded perspective view (b), and the longitudinal cross-sectional view (c) cut | disconnected in front of the protruding electrode member. It is the perspective view (a), the exploded perspective view (b), and the longitudinal cross-sectional view (c) which show the comparative example 1 of the surge absorber which concerns on this invention, and its manufacturing method. It is the perspective view (a) which shows the comparative example 2 of the surge absorber which concerns on this invention, and its manufacturing method, an exploded perspective view (b), and the longitudinal cross-sectional view (c) cut | disconnected in front of the protruding electrode member.

  A first embodiment of a surge absorber and its manufacturing method according to the present invention will be described below with reference to FIG. In each drawing used for the following description, the scale is appropriately changed in order to make each member recognizable or easily recognizable.

  As shown in FIG. 1, the surge absorber 1 according to the present embodiment includes an insulating tube 2 and a pair of sealing electrodes 3 that closes both ends of the insulating tube 2 and seals a discharge control gas therein. And a protruding electrode member 4 having a base end fixed to the conductive sealing material H on one of the pair of sealing electrodes 3 and a tip protruding toward the other.

The protruding electrode member 4 has a hole 4a formed from the proximal end to the distal end. In the present embodiment, the protruding electrode member 4 is a cylindrical member in which a through hole is formed on the central axis as a hole 4a, and is made of Cu.
The conductive fusing material H contains a metal having a higher electron emission capacity than the sealing electrode 3 and extends from the base end to the front end in the hole 4a. Further, a reservoir portion Ha of the conductive fusion material H is formed at the tip of the protruding electrode member 4. This conductive fusing material H is a brazing material containing Ag as a metal having a higher electron emission ability than the sealing electrode 3, and is formed of an Ag—Cu brazing material as a brazing material containing Ag, for example.

The insulating tube 2 is a ceramic casing, and is formed of a rectangular cylinder-shaped ceramic material whose outer shape is a prism and is hollow. The insulating tube 2 is preferably a crystalline ceramic material such as alumina, but a glass tube such as lead glass may be adopted.
Further, a trigger portion 5 made of a conductive material is provided on the inner peripheral surface of the insulating tube 2 and in the middle portion of the pair of sealing electrodes 3. The trigger unit 5 is a carbon trigger formed of, for example, a carbon material. In addition to the elliptical film shape as shown in FIG. 1, the trigger portion 5 may be formed in a dot shape or a linear shape in the axial direction or the circumferential direction of the insulating tube 2. The trigger portion 5 may not be formed according to desired characteristics.

The sealing electrode 3 is a square plate-like electrode part, and is fixed in close contact with the opening at both ends of the insulating tube 2 by a heat treatment with the conductive fusing material H.
The discharge control gas sealed in the insulating tube 2 is an inert gas or the like, for example, He, Ar, Ne, Xe, Kr, SF ₆ , CO ₂ , C ₃ F ₈ , C ₂ F ₆ , CF ₄ , H ₂ , the atmosphere, etc. and a mixed gas thereof are employed.

Next, the manufacturing method of the surge absorber 1 of this embodiment is demonstrated.
The manufacturing method of the surge absorber 1 includes an assembling step of closing the opening portions at both ends of the insulating tube 2 with a pair of sealing electrodes 3 with the discharge control gas and the protruding electrode member 4 inside, and a pair of sealing members. The pair of sealing electrodes 3 and the insulating tube 2 are fixed to each other by the conductive fusing material H provided on the inner surface of the stop electrode 3 and one of the pair of sealing electrodes 3 and the base end of the protruding electrode member 4 are fixed to each other. Fixing process.

In order to produce this surge absorber 1, first, an insulating tube 2 having a trigger portion 5 formed on the inner surface is prepared, and a cylindrical shape in which a through hole is formed as a hole portion 4 a formed from the proximal end to the distal end. The protruding electrode member 4 is prepared.
Next, a conductive fusing material H having a predetermined thickness is disposed on the joint surface of the insulating tube 2 and the inner surface of the sealing electrode 3, and the protruding electrode member 4 is electrically conductive on the inner surface of one sealing electrode 3. After the air in the insulating tube 2 is replaced with a predetermined discharge control gas (for example, Ar) while standing on the dressing H, it is closely fixed by heat treatment.

  That is, one sealing electrode 3, plate-like conductive fusing material H, insulating tube 2, protruding electrode member 4, plate-like conductive fusing material H and the other sealing electrode are placed in the hole of the heater. Insert in order of 3. In this state, the air in the insulating tube 2 is replaced with a predetermined discharge control gas (for example, Ar), and then the sealing electrode 3 is pressed and adhered to both ends of the insulating tube 2 and heated.

At this time, the conductive melt H heated and melted extends from the proximal end to the distal end of the protruding electrode member 4 in the hole 4a by capillary action. That is, the hole 4a of the protruding electrode member 4 is set to an inner diameter that allows the molten conductive fusion material H to climb up to the tip by capillary action. In addition, it is preferable that the conductive fusing material H is crawled up until a brazing material puddle is formed at the tip of the protruding electrode member 4.
Accordingly, the sealing electrode 3 and the insulating tube 2 are sealed with the conductive fusion material H, thereby sealing the discharge control gas in the insulating tube 2 and fixing the protruding electrode member 4. Then, the surge absorber 1 is manufactured by further increasing the conductive fusion material H to the tip of the protruding electrode member 4.

  In this surge absorber 1, when an overvoltage or overcurrent enters, trigger discharge is first performed between the trigger portion 5 and the conductive fusion material H (reservoir portion Ha) at the tip of the protruding electrode member 4. As a result, the discharge further progresses and the discharge is performed between the pair of sealing electrodes 3 to absorb the surge.

  As described above, in the surge absorber 1 of the present embodiment, the conductive fusion material H contains a metal having a higher electron emission capacity than the sealing electrode 3 and is formed from the base end to the tip end of the protruding electrode member 4. Since it extends from the base end to the tip in the portion 4a, the conductive fusion material H having a high electron emission ability reaches and reaches the tip of the protruding electrode member 4 serving as a discharge start surface. There is no need to apply an electron emitter, and a stable low discharge start voltage can be obtained.

That is, since the protruding electrode member 4 is a cylindrical member having a through hole formed therein as a hole 4a, it has a high electron emission ability extending into the hole 4a of the cylindrical member and reaching the tip. The conductive fusion material H can be discharged.
In particular, since the reservoir portion Ha of the conductive fusing material H is formed at the tip of the protruding electrode member 4, the presence of a metal having a high electron emission ability at the tip makes it possible to achieve a more stable and low voltage. Discharging can be started.

In addition, since the conductive fusing material H that has been heated and melted in the fixing process extends from the proximal end to the distal end of the protruding electrode member 4 by capillarity, the holes are separately provided before the assembling process. There is no need to produce the protruding electrode member 4 provided with the conductive bonding material H in the portion 4a, and the conductive bonding material H can be extended to the tip of the protruding electrode member 4 simultaneously in the fixing step. Therefore, it is possible to reduce the manufacturing process and the manufacturing cost.
Furthermore, since the hole 4a is formed in a path that is the shortest distance from the base end to the tip of the protruding electrode member 4, the conductive fusing material H melted in the fixing process reaches the tip at the shortest distance by capillary action. It is possible to crawl up and to reliably extend the conductive fusion material H from the proximal end to the distal end.

  Next, 2nd and 3rd embodiment of the surge absorber which concerns on this invention is described below with reference to FIG.2 and FIG.3. In the following description of each embodiment, the same constituent elements described in the above embodiment are denoted by the same reference numerals, and the description thereof is omitted.

The difference between the second embodiment and the first embodiment is that, in the first embodiment, the protruding electrode member 4 is a cylindrical member in which a through hole is formed as a hole portion 4a. In the surge absorber 21 of the embodiment, as shown in FIG. 2, the protruding electrode member 24 is a column member in which a groove portion 24 a is formed on a side surface. That is, in the protruding electrode member 24 of the second embodiment, a groove portion 24a cut into a substantially V-shaped cross section is formed along the central axis on the outer peripheral surface of a columnar member, and the groove portion 24a The conductive fusing material H that has been melted in the fixing process and crawled up by the capillary phenomenon extends.
Therefore, in the surge absorber 21 of the second embodiment, since the protruding electrode member 24 is a column member having a groove portion 24a formed on the side surface, it has a high electron emission ability that extends into the groove portion 24a and reaches the tip. The conductive fusion material H can be discharged.

  The difference between the third embodiment and the first embodiment is that the protruding electrode member 4 is a cylindrical member in which a through hole is formed as a hole 4a inside, whereas the surge absorber 31 of the third embodiment. Then, as shown in FIG. 3, the protruding electrode member 34 is a metal plate member formed by bending a plate material to form a gap-shaped groove 34 a.

  The protruding electrode member 34 of the third embodiment is formed by bending a rectangular Cu plate at two locations so as to obtain a gap-shaped groove portion 34a in which the molten conductive adhesive H is scooped up by capillary action. ing. In other words, the Cu plate is folded by performing a folded fold by performing a mountain fold and a valley fold. Thus, the protruding electrode member 34 is obtained. In addition, when the Cu plate is bent, the bending angle is set so that at least one gap-like groove portion 34a from which the conductive fusion material H scoops up by capillary action is obtained, and the protruding electrode member 34 can be erected. Bend like so.

  Therefore, in the surge absorber 31 of the third embodiment, the protruding electrode member 34 is a metal plate member formed by bending a plate material to form a gap-like groove portion 34a, and thus extends into the gap-like groove portion 24a of the plate material. Then, it can be discharged by the conductive fusing material H having a high electron emission ability reaching the tip.

  Next, the results of evaluating the surge absorber according to the present invention and the method for manufacturing the same according to an example actually produced based on the above embodiment will be specifically described.

Typically, as an example of the surge absorber 31 of the third embodiment, a protruding electrode member 34 having a height of 2.8 mm is provided in the insulating tube 2 having a length of 3.3 mm and a cross-sectional dimension of 3.2 mm × 2.3 mm. Example 1 was made upright. In addition, the distance from the front-end | tip of the protruding electrode member 34 to the electroconductive fusion material H which opposes is 0.5 mm.
For Example 1, a DC discharge start voltage V _s (unit V) and a discharge start voltage V _imp (unit V) when 1.2 / 50 6 kV was applied were measured, and V _imp / I was asked to V _s. Note that V _imp / V _s is more excellent in response as it is closer to “1”.

For comparison, as a surge absorber 101 described in Patent Document 1, as shown in FIG. 4, a swelled electrode material made of a conductive fusing material H whose center portion is raised on the inner surface of the sealing electrode 3. Comparative Example 1 in which was formed. In addition, as Comparative Example 2, a pair of Cu columnar electrode members 104 protruding in an opposed state and standing on the inner surfaces of the pair of sealing electrodes 3 via an inner electrode 106 are provided. A surge absorber 121 having an electron emitting agent (cesium compound) coated on the surface was also produced. And also about these comparative examples, the same measurement as Example 1 was performed.
The dimensions of the insulating tube 2 of Comparative Examples 1 and 2 are the same as those of Example 1. The pair of columnar electrode members 104 of Comparative Example 2 had a height of 1.4 mm and a diameter of 1.0 mm, and the distance between them was 0.5 mm. These results are shown in Table 1.

As can be seen from these results, only there is no protruding electrode member 4, as compared with Comparative Example 1 is substantially the same structure, the first embodiment DC discharge starting voltage V _s and 6kV is applied at the discharge starting voltage of the present invention V _imp has dropped significantly. In addition, when Example 1 of the present invention is compared with Comparative Example 2, in Example 1, the discharge start voltage V _imp when 6 kV is applied is low although the DC discharge start voltage V _s is about 100 V high. It can be seen that the response is excellent.

  The technical scope of the present invention is not limited to the above embodiments and examples, and various modifications can be made without departing from the spirit of the present invention.

  1, 21, 31, 101, 121 ... surge absorber, 2 ... insulating tube, 3 ... sealing electrode, 4, 21, 31 ... projecting electrode member, 4a ... hole, 24a, 34a ... groove, 5 ... trigger part , H: conductive adhesive, Ha: reservoir

Claims (8)

An insulating tube;
A pair of sealing electrodes for closing the opening at both ends of the insulating tube and sealing the discharge control gas inside;
A projecting electrode member having a proximal end fixed to one of the pair of sealing electrodes with a conductive adhesive and a distal end projecting toward the other;
The protruding electrode member has a groove or a hole formed from the base end to the tip,
The surge absorber, wherein the conductive fusing material contains a metal having a higher electron emission capacity than the sealing electrode, and extends from the base end to the tip end in the groove or the hole. The surge absorber according to claim 1,
A surge absorber characterized in that a reservoir of the conductive fusion material is formed at the tip of the protruding electrode member. The surge absorber according to claim 1 or 2,
A surge absorber, wherein the protruding electrode member is a cylindrical member having a through hole formed therein as the hole. The surge absorber according to claim 1 or 2,
The surge absorber according to claim 1, wherein the protruding electrode member is a column member having the groove formed on a side surface. The surge absorber according to claim 1 or 2,
The surge absorber according to claim 1, wherein the protruding electrode member is a metal plate member in which the groove-like groove is formed by a bent plate material . In the surge absorber according to any one of claims 1 to 5,
The protruding electrode member is made of Cu;
A surge absorber, wherein the conductive fusing material is a brazing material containing Ag. A method of manufacturing the surge absorber according to any one of claims 1 to 6,
An assembly process of closing both ends of the insulating tube with a pair of sealing electrodes in a state where the discharge control gas and the protruding electrode member are placed inside,
The conductive sealing material provided on the inner surfaces of the pair of sealing electrodes secures the pair of sealing electrodes and the insulating tube, and one of the pair of sealing electrodes and the base end of the protruding electrode member A fixing process for fixing
The protruding electrode member has a groove or a hole formed from the base end to the tip,
The conductive fusion material contains a metal having a higher electron emission capacity than the sealing electrode,
A surge absorber characterized in that, in the fixing step, the conductive fusion material heated and melted extends from the proximal end to the distal end of the protruding electrode member in the groove or the hole by a capillary phenomenon. Production method. In the manufacturing method of the surge absorber according to claim 7,
The method of manufacturing a surge absorber, wherein the groove or the hole is formed by a path having a shortest distance from a base end to a tip end of the protruding electrode member.

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