JPS642510Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a gas-entered lightning arrester as a communication safety element that reliably protects against open destruction.

[Prior Art] As this type of gas-filled lightning arrester element, a protector circuit is constructed by combining devices that discharge high voltage to the earth, such as a button-shaped gas-filled discharge tube. The above-mentioned gas lightning arrester element opens and breaks down in an overloaded state, resulting in a dangerous situation in which current flows into the extension line side. From the standpoint of fail-safety, it is desired to reliably detect open failure of gas-filled lightning protection elements and cause short-circuit failure.

[Problems to be Solved by the Invention] However, the gas-filled lightning arrester described above needs to be equipped with various short-circuit mechanisms to prevent open damage.
Currently proposed short-circuit mechanisms of this type include:
The heat generated during overload of gas-filled lightning protection elements melts the low-temperature molten alloy (for example, solder) inside the element, causing a short circuit, but as the discharge induces impure gas from the solder, the discharge Not only does it affect the characteristics, but if the lightning arrester element is heat-sealed with solder inside, impurity gas is likely to be generated during gas sealing, and degassing processing must be performed more than necessary. This complicated the manufacturing process. In particular, in this case, even when the lightning arrester itself is not destroyed by heat, it is susceptible to short-circuiting due to melting of the solder, making it impossible to make full use of the power of the gas lightning arrester.

In order to solve this problem, there are some devices in which solder is provided on the outer surface of the gas-entering lightning arrester element, and the melting of the solder short-circuits the metal pieces with a spring. Although it is not a gas-filled lightning arrester with a similar short-circuit structure, it is
As shown in Japanese Patent No. 121230, a structure is disclosed in which a varistor is covered with a half-cylindrical dish-shaped metal piece and pressurized from the outside with a spring.

In any case, it is easy to break down due to looseness in the installation or handling of the metal piece, the mounting structure for the external spring becomes large, and dust accumulates in the movement space of the metal piece during long-term use, preventing it from operating properly. An accident had occurred.

In addition, the structure and manufacturing and installation process are complicated, and the installation to the protector device is not universal.

Therefore, in order to eliminate the above drawbacks, the present invention has the following features:
The purpose of the present invention is to provide a shorting plate that can be detachably attached to a gas lightning arrester, has a simple structure, can be immediately attached to the gas lightning arrester of a communication safety device currently in use, and is easy to use. Its purpose is to make it possible to exchange it with other people.

[Means for Solving the Problems] The present invention for solving the above object is attached to a gas-entered lightning arrester which is formed by sealing the openings of an insulating tube with metal electrodes and sealing the inside with gas. It is a metal shorting plate, and the shorting plate is approximately U-shaped, consisting of a base along the insulating tube and a pair of springy contact pieces that are bent oppositely from the upper and lower edges of the base to press the end surface of the metal electrode. A low-temperature melting insulator is provided on the opposing surface of the contact piece, which is always separated from the end surface, melts by discharge heat during overload, and is brought into contact with the end surface when the pressure is applied. The configuration is as follows.

[Function] If a roughly U-shaped contact piece is applied to the end face of the metal electrode of the gas-entering lightning protection element, and pushed through the U-shaped opening against the spring force, they will be separated by the low-temperature melting insulator. It is installed in the same position. The separated state is maintained at all times.

If a high current is applied in such a separated state and discharge heat is generated due to continuous discharge of the gas lightning arrester element, the end face of the metal electrode, which is the discharge location, will generate heat and the low-temperature melting insulator will melt. Along with this, the shorting plate short-circuits both metal electrodes according to the spring force.

[Example] Figures 1 to 5 show an example implemented in a button-type gas-entering lightning arrester. Figure B is a side view showing a state in which the lightning arrester is attached to a gas-entered lightning arrester element at a pole, and Figure B is a side view showing the same in a short-circuited state.

In the figure, A is a two-pole gas lightning arrester, B is an insulated tube, C is a metal electrode that seals both end openings of the insulated tube B and gas is sealed inside, C1 is the end face of the metal electrode C, and C2 is the peripheral surface of the metal electrode C.

Therefore, 1 is a short circuit plate according to the present invention, and the short circuit plate 1
is formed of a metal plate with good conductivity, and has a U-shape consisting of a base 2 and contact pieces 3, 3, which are bent at approximately right angles from the upper and lower edges of the base 2 and placed facing each other.
The contact piece 3 has a spring property that presses the opposing surface,
A guide portion 4 is provided by curving its free end. The opposing surfaces of the contact pieces 3, 3 can be coated with insulating layers 5, 5, respectively, which are melted by discharge heat during overload. Here, the term "overload" refers to a state of destruction due to continued discharge, a state of deterioration of the discharge characteristics but not destruction, and a state immediately before deterioration of the discharge characteristics. Moreover, melting is a concept that includes softening. As the insulating layer 5, an insulating material such as a thermoplastic synthetic resin is selected which melts only when the gas lightning arrester A is on the verge of destruction due to discharge heat. Similarly,
The overload condition is determined by selecting an insulator that melts for the first time due to the discharge heat that degrades the discharge characteristics of the gas lightning arrester A, or the discharge heat just before that, or by determining the thickness of the insulating layer.

Further, as shown in FIG. 3, the short circuit board 1 has auxiliary metal plates 6, 6 interposed between the insulating layers 5, 5, respectively, and a display device X1 for displaying the short circuit state on the auxiliary metal plates 6, 6. , X2. In this case, if the insulating layers 5, 5 are melted, the metal electrodes C,
C, the auxiliary metal plates 6, 6, and the shorting plate 1 come into contact with each other and short-circuit, and at the same time, the short-circuit condition is electrically displayed by the display device.

As shown in FIG. 4, when implementing a short circuit plate in a multi-pole gas lightning arrester, clamping pieces 7 and 8 are provided facing each other from the left and right edges of the base 2, and between the clamping pieces 7 and 8, The intermediate electrode D is directly contacted and held between the electrodes. In this case, if any one of the metal electrodes C and the contact piece 3 come into contact, a short circuit can be established immediately, and the metal electrode C can be held between the four pieces to ensure reliable attachment.

Next, to install the shorting plate 1, apply the guide parts 4, 4 to the end face parts C1, C1 of the gas lightning arrester A, and press the base 2. Using the guide parts 4, 4 as a guide, insulating layers 5, The contact pieces 3, 3 isolated from each other are connected to the end face C
1, it is installed in a state where C1 is sandwiched. If a sustained current is applied in this state and discharge heat is generated, the insulating layers 5, 5 will melt when the gas lightning arrester A is overloaded, and the contact pieces 3, 3 will be compressed by the clamping force between the metal electrodes C,
C and short circuit. Since the short-circuit condition is visible to the naked eye, it is possible to replace it. If a short circuit occurs before destruction, the short-circuited short-circuit plate 1 is removed from the gas lightning arrester element, and a new short-circuit plate 1 is attached to restore the insulation state.

Furthermore, as shown in FIG. 5, a gas lightning arrester having a terminal E is implemented by providing a terminal gap 9 in the contact piece 3. In this case, the insulating layer 5 is exposed from the terminal gap 9 into the gap to achieve complete insulation.

[Effects of the Invention] According to the present invention, the following effects are achieved when the gas lightning arrester element is provided with fail-safe properties.

Since the shorting plate is U-shaped, it can be easily installed by simply pressing it against the end of the electrode.There is no need to make any modifications to existing gas lightning arresters or various protectors, and it can be used exclusively for gas lightning arresters. We were able to put this into practical use as an adapter with a fail-safe mechanism.

Since the low-temperature melting insulator is directly and closely pressed with a contact piece to the electrode end surface, which is the discharge point, there is no need to use heat to operate other mechanisms. Since there are no short circuits, highly accurate short circuits can be performed.

Since the shorting plate is formed into a substantially U-shape, it can be miniaturized along the outside of the gas lightning arrester element and can be installed without wasting space.

Since the short-circuit state of the short-circuit plate can be visually observed, it can be distinguished from other non-faulty gas lightning arresters, and the burden of periodic inspection work can be reduced.

[Brief explanation of the drawing]

The drawings show an embodiment of the shorting plate of the gas lightning arrester according to the present invention, in which Fig. 1 is a perspective view thereof, Fig. 2A is a side view showing the installed state, and Fig. 2B is a side view showing the shorted state. Figure 3 is a side view showing the state in which it is connected to another display device, Figure 4 is a side view showing the state in which it is attached to a three-pole gas lightning arrester, and Figure 5 is a gas lightning arrester with terminals. FIG. 3 is a perspective view showing a state where the device is attached. A... Gas lightning arrester element, C... Metal electrode, C1...
... End face part, 1 ... Short circuit plate, 2 ... Base, 3 ... Contact piece, 4 ... Guide part, 5 ... Low temperature melting insulator.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A metal short-circuit plate attached to a gas-entry lightning arrester formed by sealing the openings of an insulating tube with metal electrodes and sealing the inside with gas, This short-circuiting plate has a substantially U-shape consisting of a base along the insulating tube and a pair of contact pieces bent oppositely from the upper and lower edges thereof and having spring properties to press the end face of the metal electrode. A gas-filled lightning protection element for communications, in which a low-temperature melting insulator is provided on the face, which is always spaced apart from the end face, melts by discharge heat during overload, and comes into contact with the end face as the pressure is applied. Short circuit board. (2) The short-circuiting plate for a communication gas lightning arrester according to claim 1, wherein a guide portion is provided at the free end of the contact piece.