JPH113764A - Discharge tube type surge absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discharge tube type surge absorber which is capable of preventing the deterioration in the surge protecting characteristic, effectively absorbing surges entering into electronic equipment and preventing the malfunction of an electronic circuit in the electronic equipment. SOLUTION: Four grooves 13 are threadedly provided at equal spaces on the side face of a cylindrical insulating material formed of corundum mullite to manufacture a base 11, which is disposed in a glass tube 14 and held between slag leads 12 to make the slag leads 12 adhere to both ends of the glass tube 14 into the condition that the inside of the glass tube 14 is sealed with Ar gas. In this way, a time from starting discharge until arc discharge is longer, so that the malfunction of an electronic circuit in electronic equipment due to high frequency current is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge tube type surge absorber that protects an electronic device from an abnormal voltage (surge) that enters the electronic device from the outside via a power supply line or the like attached to the electronic device.

[0002]

2. Description of the Related Art Conventionally, a surge absorber for absorbing a surge has been used to protect an electronic device from a surge. As the surge absorber, a varistor, a discharge tube type surge absorber and the like are known. The varistor is
The resistance decreases as the applied voltage increases.If a varistor is used as a surge absorber, if a surge enters an electronic device from the outside, the resistance of the varistor decreases due to the surge, and a large current flows through the varistor. Flows. Therefore, the surge is absorbed by the varistor,
Electronic equipment is protected from excessive surge.

A discharge tube surge absorber is a discharge tube that discharges when a voltage exceeding a predetermined voltage is applied.
As a discharge tube type surge absorber, a microgap type or the like is known. When a discharge tube type surge absorber is used for the surge absorber, similar to the case of the varistor,
When a surge enters an electronic device from the outside, the surge absorber discharges to absorb the surge,
Electronic equipment is protected from excessive surge.

[0004]

The above-mentioned varistor has a problem that the surge protection characteristic of the varistor is deteriorated because the residual voltage after absorbing the surge is higher than the operating voltage of the varistor. Further, in the discharge tube type surge absorber, an arc discharge is generated in a very short time after the discharge starts, so that a large current flows in a short time. Therefore, a high-frequency current is generated,
There is a problem that the electronic circuit of the electronic device may malfunction due to the current.

To prevent the generation of such a high-frequency current, a resistor may be connected in series to the discharge tube type surge absorber. However, if the resistor is connected, a voltage is generated in the resistor when the surge is absorbed, which also results in surge protection. There is a problem that characteristics are deteriorated. The present invention has been made in view of the above circumstances, and provides a discharge tube type surge absorber in which deterioration of surge protection characteristics is prevented, a surge invading an electronic device is effectively absorbed, and a malfunction of an electronic circuit in the electronic device is prevented. The purpose is to:

[0006]

A discharge tube type surge absorber according to the present invention, which achieves the above object, comprises an insulating base, a pair of conductive electrodes sandwiching the base from both ends, and an insulating base for sealing the base. And a groove formed as a spiral discharge path between the base and the inner wall of the outer tube, the base being screwed on the surface of the base.

[0007] If a spiral groove forming a discharge path is screwed on the surface of the base, the inductance between the electrodes at the time of discharge increases as compared with the case where the discharge path is linear. This makes it possible to lengthen the time required to perform the operation, suppress steep current changes, and reduce the occurrence of high-frequency current. Therefore, when the electronic device is protected from a surge by using the discharge tube type surge absorber of the present invention, malfunction of an electronic circuit of the electronic device due to a high-frequency current is prevented. Also, it is not necessary to connect a resistor to the discharge tube surge absorber to weaken the high-frequency current,
A discharge tube type surge absorber in which the deterioration of the surge protection characteristic is prevented can be obtained.

Here, in the discharge tube type surge absorber of the present invention, a plurality of grooves forming independent discharge paths may be screwed between the pair of electrodes on the surface of the base. Further, the discharge tube type surge absorber of the present invention may have a gap portion in which a pair of conductors face each other at a predetermined interval in a part of a discharge path in a sealed space surrounded by the outer tube. Good.

[0009]

Embodiments of the present invention will be described below. FIG. 1 is a side view showing a discharge tube type surge absorber according to a first embodiment of the present invention. FIG. 2 is a side view of a base constituting the discharge tube type surge absorber shown in FIG.
Is a perspective view thereof.

A discharge tube type surge absorber 10 shown in FIG.
Has a columnar base 11. The base 11 is an insulating base. At both ends of the base 11, a pair of conductive slag leads 12 sandwiching the base 11 from both ends are provided. As shown in FIG. 3, four grooves 13 forming independent discharge paths are screwed between a pair of slag leads 12 on the side surface of the base 11. The discharge tube surge absorber 10 includes a glass tube 14 for sealing the base 11 in an inert gas in cooperation with a slag lead 12, as shown in FIG. The convex portion 15 between the adjacent grooves 14 on the side surface of 11
Is formed in a size to be in close contact with the inner wall of the glass tube 14.

In the discharge tube surge absorber 10 configured as described above, the grooves 13 forming a spiral discharge path are formed on the side surface of the base 11, so that the discharge tube surge absorber 10 has a discharge compared to a case where the discharge path is linear. The inductance between the pair of slag leads 12 at the time increases. Therefore, it takes a long time to reach the arc discharge from the start of the discharge, and the high-frequency current is weakened.

FIG. 4 is a side view showing a discharge tube surge absorber according to a second embodiment of the present invention. FIG. 5 is a side view of a base constituting the discharge type surge absorber shown in FIG.
Is a perspective view thereof. The same components as those of the embodiment shown in FIGS. 1 to 3 are denoted by the same reference numerals,
Only differences from the embodiment shown in FIGS. 1 to 3 will be described.

A discharge tube type surge absorber 20 shown in FIG.
As shown in FIG. 5, a conductive film 22 is formed on the inner wall of each of the four grooves 13 screwed on the side surface of the base body 11 to form a gap 21 extending in the width direction of the groove 13. I have. Here, only one gap 21 is shown, but other gaps are formed at positions that cannot be seen from FIGS. 4, 5, and 6.

As described above, when the conductive film sandwiching the gap is formed in the groove formed on the side surface of the base, the discharge starting voltage can be lower than that of the discharge tube type surge absorber shown in FIG. FIG. 7 is a side view showing a discharge tube type surge absorber according to a third embodiment of the present invention, FIG. 8 is a side view showing a base constituting the discharge tube type surge absorber shown in FIG. 7, and FIG. FIG.

A discharge tube surge absorber 30 shown in FIG.
Is, as shown in FIG. 8, a cylindrical insulating base 31;
It has two columnar insulating substrates 32 sandwiching the substrate 31 from both ends. As shown in FIGS. 7 to 9, the two bases 32 are provided so as to sandwich the base 31 from both ends, as shown in FIGS. 7 to 9. Further, as shown in FIG. A pair of conductive slag leads 33 sandwiched from both ends are provided. As shown in FIG. 9, each base 32 is provided with four grooves 34, each forming a discharge path independent of each other, on the side surface thereof, and a conductive film is formed on the inner wall of each of the four grooves 34. Are formed. In addition, a conductive film 36 is formed on the base 31 so as to sandwich a gap 35 provided so as to make a round around the side surface in the circumferential direction. The discharge tube surge absorber 30
As shown in FIG. 7, a glass tube 37 that seals the three substrates 31 and 32 in an inert gas in cooperation with a pair of slag leads 33 is provided. The convex portion 38 between the side grooves 34 is a glass tube 3
7 is formed to have a dimension to be in close contact with the inner wall.

In the discharge tube type surge absorber 30, a discharge is generated in a gap 35 between the conductive films 36 formed on the base 31, so that a discharge forming a linear discharge path in the part of the base 31 is generated. As a result, a discharge forming a spiral discharge path is generated at the base 32 portion. In this way, a discharge tube type surge absorber having a structure in which a discharge forming a spiral discharge path is generated may be provided in a part between the pair of slag leads 33.

FIG. 10 is a side view showing a discharge tube type surge absorber according to a fourth embodiment of the present invention. FIG. 11 is a side view showing two bases constituting the discharge tube type surge absorber shown in FIG. FIG. 12 is a perspective view thereof. The discharge tube surge absorber 40 shown in FIG. 10 includes two columnar insulating bases 41 as shown in FIG. A discharge electrode 42 is attached to one end of each of the two bases 41, as shown in FIGS. This 2
The two bases 41 are arranged so that the discharge electrodes 42 attached to their one ends face each other. Further, as shown in FIG. 10, a pair of conductive slag leads 43 are fixed to the base 41. ing. A groove 44 forming a discharge path is formed on the side surface of each of the two bases 41, as shown in FIG.
As shown in FIG. 2, four threads are provided, and a conductive film is formed on the surface of the base 41 on which the four grooves 44 are provided. This discharge tube surge absorber 30 is
In cooperation with the pair of slag leads 43, a glass tube 45 for sealing the two substrates 41, on which the discharge electrodes 42 are attached, in an inert gas is provided. Convex portion 46 between matching grooves 44
Are formed to have dimensions that are in close contact with the inner wall of the glass tube 45.

In this discharge tube type surge absorber 40, a discharge is generated between the discharge electrodes 42, so that a discharge forming a linear discharge path is generated at the discharge electrode 42,
Discharge forming a spiral discharge path is generated in the two base portions 41.

[0019]

An embodiment of the present invention will be described below.
As Examples 1, 2, 3, and 4, the discharge tube type surge absorbers 10, 20, 30, and 40 of the respective embodiments shown in FIGS. 1, 4, 7, and 10 were manufactured. And an arrester as Comparative Example 2 was manufactured. The following is the discharge tube type surge absorber 1
After the manufacturing processes of 0, 20, 30, and 40 are sequentially described, the manufacturing process of the discharge tube surge absorber of Comparative Example 1 and the arrester of Comparative Example 2 will be described. Then, Examples 1, 2, 3,
DC discharge start voltage, impulse discharge start voltage, discharge tube type surge absorber of Comparative Example 4, discharge tube type surge absorber of Comparative Example 1, and arrester of Comparative Example 2.
The result of measuring the impulse absorption time will be described.

In manufacturing the discharge tube type surge absorber 10 having the structure shown in FIG. 1, first, a cylindrical insulating material was prepared. In this example, corundum mullite was fired to produce an insulating material having a diameter of 3 mm at both ends and a length of 3 mm. Here, corundum mullite is used as the insulating material, but alumina, zirconia, corundum, mullite, or the like, or a mixture of materials having high magnetic permeability may be used.

Next, four sides of the insulating material are equally spaced.
The groove 13 of the book was screwed, and the base 11 as shown in FIG. 3 was manufactured. In this example, the depth and width of the groove were set to 1.2 mm and 0.75 mm, respectively, and the interval between adjacent grooves was set to 0.1 mm. Next, the base 11 is attached to the glass tube 14.
The glass tube 14 is disposed inside, the base 11 is sandwiched between slag leads 12, and the base 11 is sealed in Ar gas.
And the slag lead 12 were bonded. Ar gas pressure is 8
00 Torr.

Thus, a discharge tube type surge absorber 10 having the structure shown in FIG. 1 was manufactured. In manufacturing the discharge tube type surge absorber 20 having the structure shown in FIG. 4, first, the same material and the same dimensions as those of the base body having four grooves on the side surface manufactured in the process of manufacturing the discharge tube type surge absorber 10 shown in FIG. Was manufactured. Next, a conductive film is formed on the inner wall of each of the four grooves 13 formed on the side surface of the base 11, and the conductive film is cut in each of the conductive films in each groove in the width direction of the groove 13. Such a gap 21 was formed. In this embodiment, the width of the gap is set to 30 μm.

Next, the substrate 11 having the conductive film 22 formed on the inner wall of the groove 13 is placed inside the glass tube 14 and
1 was sandwiched between slag leads 12, and the glass tube 14 and the slag lead 12 were bonded together in a state where the substrate 11 was sealed in Ar gas. The pressure of the Ar gas was 800 Torr.
Thus, the discharge tube type surge absorber 20 having the structure shown in FIG. 4 was manufactured.

A discharge tube type surge absorber 30 shown in FIG.
First, two insulating bases 32 having the same material and the same dimensions as the insulating base having four grooves on the side surface manufactured in the manufacturing process of the discharge tube type surge absorber 10 shown in FIG. Then, a conductive film was formed on the inner walls of the four grooves 34 of each of the two insulating substrates 32. Separately from the insulating base 32, a cylindrical insulating base 31 made of corundum mullite having a diameter of both ends of 0.6 mm and a length of 1 mm is prepared. Was formed on the surface of the substrate 31, and a gap 35 was formed so as to circumnavigate the side surface of the base 31 in the circumferential direction so as to divide the conductive film into two. Gap 3
The width of 5 was 30 μm.

Next, the base 31 and the two bases 32 are
The substrate 31 is disposed in the glass tube 37 so as to sandwich the substrate 31 from both ends, and the three substrates 31 and 32 are further disposed.
The slag lead 33 was arranged so as to sandwich the entirety of the substrate from both sides, and the glass tube 37 and the slag lead 33 were bonded to each other while the substrates 31, 32 were sealed in Ar gas. The pressure of the Ar gas was 800 Torr.

Thus, a discharge tube type surge absorber 30 having the structure shown in FIG. 7 was manufactured. In manufacturing the discharge tube type surge absorber 40 having the structure shown in FIG. 10, first, the same material and the same dimensions as those of the insulating base having four grooves on the side surface manufactured in the process of manufacturing the discharge tube type surge absorber 10. Two insulating substrates 41 were manufactured. Next, a conductive film was formed on the surface of each of the two substrates 41.

Next, a discharge electrode 42 was attached to one end surface of each of the two substrates 41. Next, the two substrates 41 to which the discharge electrodes 42 are attached are separated from each other by one.
are disposed inside the glass tube 45 so as to face each other with an interval of mm, and slag leads 43 are arranged on both sides of the two bases 41 as a whole. In a state where these two bases 41 are sealed in Ar gas, The glass tube 45 and the slag lead 43 were bonded. The pressure of the Ar gas was 800 Torr.

Thus, a discharge tube type surge absorber 40 having the structure shown in FIG. 10 was manufactured. In manufacturing the discharge tube type surge absorber of Comparative Example 1, a cylindrical insulating material was prepared. Here, corundum mullite was fired as an insulating material, and both ends were 1 mm in diameter and 3 mm in length.
mm was prepared and used as a substrate.

Next, a conductive film was formed on the surface of the substrate. Further, cap-shaped cap electrodes were press-fitted at both ends of the base on which the conductive film was formed, and a gap was formed around the side surface of the base in a circumferential direction so as to divide the conductive film into two. The width of the gap was 30 μm. afterwards,
An insulating substrate having a gap formed therein is arranged inside a glass tube, slag leads are arranged on both sides, and the inside of the glass tube is A
A slag lead was bonded to the glass tube while being sealed in r gas. The pressure of the Ar gas was 800 Torr.

Thus, the discharge tube type surge absorber of Comparative Example 1 was manufactured. In manufacturing the arrester of Comparative Example 2, a sealing electrode having an outer diameter of 4 mm and a sealing portion having a thickness of 1 mm provided with a discharging portion having a diameter of 1 mm and a thickness of 0.5 mm was provided with an outer diameter of 4 mm and an inner diameter of 3 mm. The glass tube and the sealing electrode were adhered in a state where the inside of the glass tube was sealed with Ar gas. The pressure of Ar gas is 80
0 Torr.

Thus, an arrester of Comparative Example 2 was manufactured. Table 1 shows the DC discharge start voltage, the impulse discharge start voltage, and the discharge tube type surge absorber of Examples 1, 2, 3, and 4, the discharge tube type surge absorber of Comparative Example 1, and the arrester of Comparative Example 2, respectively. The result of measuring the impulse absorption time is shown. The impulse absorption time is the time from the start of discharge to the time when the arc voltage is reached.

[0032]

[Table 1]

As can be seen from Table 1, Examples 1, 2 and
The impulse absorption times of the discharge tube type surge absorbers 3 and 4 are longer than the impulse absorption time of the discharge tube surge absorber of Comparative Example 1 and the impulse absorption time of the arrester of Comparative Example 2. That is, in the case of Examples 1, 2, 3, and 4, the time from the start of discharge to the arrival of arc discharge is longer than that of Comparative Examples 1 and 2. Therefore, when the electronic device is protected from surge by using the discharge tube type surge absorber of the present invention, malfunction of the electronic circuit of the electronic device due to high frequency current is prevented. Further, the discharge tube surge absorber according to the present invention does not require connection of a resistor for reducing high-frequency current, and a discharge tube surge absorber in which deterioration of the surge protection characteristic is prevented can be obtained.

[0034]

As described above, according to the discharge tube type surge absorber of the present invention, the deterioration of the surge protection characteristic is prevented, the surge that has entered the electronic device can be effectively absorbed, and the electronic device inside the electronic device can be absorbed. Malfunction of the circuit is prevented.

[Brief description of the drawings]

FIG. 1 is a side view showing a discharge tube type surge absorber according to a first embodiment of the present invention.

FIG. 2 is a side view of a base constituting the discharge tube type surge absorber shown in FIG.

FIG. 3 is a perspective view of a base constituting the discharge tube type surge absorber shown in FIG. 1;

FIG. 4 is a side view showing a discharge tube type surge absorber according to a second embodiment of the present invention.

FIG. 5 is a side view of a base constituting the discharge tube type surge absorber shown in FIG.

FIG. 6 is a perspective view of a base constituting the discharge tube type surge absorber shown in FIG.

FIG. 7 is a side view showing a discharge tube type surge absorber according to a third embodiment of the present invention.

FIG. 8 is a side view of a base constituting the discharge tube type surge absorber shown in FIG.

FIG. 9 is a perspective view of a base constituting the discharge tube type surge absorber shown in FIG. 7;

FIG. 10 is a side view showing a discharge tube type surge absorber according to a fourth embodiment of the present invention.

FIG. 11 is a side view of a base constituting the discharge tube type surge absorber shown in FIG.

FIG. 12 is a perspective view of a base constituting the discharge tube type surge absorber shown in FIG.

[Explanation of symbols]

 10, 20, 30, 40 Discharge tube type surge absorber 11, 31, 32, 41 Insulating substrate 12, 33, 43 Slag lead 13, 34, 44 Groove 14, 37, 45 Glass tube 15, 38, 46 Convex part 21, 35 gap 22, 36 conductive film 42 discharge electrode

Claims (3)

[Claims] An insulating base, a pair of conductive electrodes sandwiching the base from both ends, and an insulating sheath tube for sealing the base, wherein the base is screwed on a surface of the base. And a groove forming a spiral discharge path between the inner surface of the outer tube and the inner wall of the outer tube. 2. The discharge tube type surge absorber according to claim 1, wherein a plurality of grooves forming independent discharge paths are screwed between said pair of electrodes on said base surface. 3. A part of a discharge path in a sealed space surrounded by the outer tube has a gap portion in which a pair of conductors face each other at a predetermined interval. Discharge tube type surge absorber.