JPS60102821A - Flash indicator - 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 The present invention relates to a device for detecting flash faults in power transmission towers caused by lightning strikes.

In recent years, with the increase in demand for electricity, power transmission lines have become larger and more trunk lines, and due to social demands, power transmission routes are being installed mainly in mountainous areas, making it easier for lightning strikes to occur. As one of the lightning protection measures, an overhead ground wire (
(ground wire), but if an electric shock falls directly on the tower and a large current flows through the tower, an abnormally high voltage will occur in the tower, exceeding the insulator's insulation ability, and causing a lightning surge to the power line. A so-called reverse flash occurs. In addition, if the power line is struck directly by lightning without the ground wire's protection, the potential of the power line will rise significantly, and at this time too, it will exceed the insulating capacity of the insulator and cause a flash, causing the earth to fall along the tower. Current flows into. Insulators are often damaged by these flash-fault accidents, and once several electrical circuits are formed, the current being transmitted may flow into the ground along the discharge circuit, resulting in a power outage. It is necessary to promptly detect the flash-faulted steel towers that are the cause of these power outages. Conventionally, gunpowder is exploded during a lightning strike, and the gas pressure of the gunpowder is used to blow off the lid and release a red display cloth. A flash indicator is used that can be easily detected by aerial patrols.

However, the flash indicator is exempted from the Explosives Control Act, so although the product may be sold and handled as a general product, the manufacturing process is subject to the Explosives Control Act. Applicable and licensed equipment and equipment are required, and the product must be manufactured within various other restrictions. In addition, if the device is activated due to a flashover accident, it is impossible to reuse it and the entire flashlight display group must be replaced, which is disadvantageous in terms of cost.

The present invention seeks to overcome the above-mentioned drawbacks and to provide a flash-flash indicator which can be manufactured without any limitations and is only partially operative.

That is, the flash fault indicator of the present invention includes a coil in which a current is induced by a change in magnetic field lines caused by a surge current caused by a lightning strike, and a heating element electrically connected to the coil so as to generate heat due to the current induced in the coil. and a guide tube containing a vertically slidable display tube provided below the heating element. The device is characterized in that it is connected by a connecting device that can be slid on.

Typical heating elements include a nonflammable, thermally conductive container, and a heat-generating resistance wire that is housed in the container and electrically connected to the coil and becomes red-hot due to the current supplied from both ends of the coil. There are things like heating agents and flash bulbs that are activated by electric current induced in a coil.

The heating element is connected to the display tube by a connector. For example, a latch is attached to the top surface of the display tube, and the linear body is fixed around the heat generating element together with the latch of the heat generating element. The linear body is made of natural fiber yarn, synthetic fiber yarn, synthetic resin strip, etc., which melts and breaks when the heating element generates heat, or it is made of a shape-memory alloy that changes its shape when the heating element generates heat. etc. are used. Although typical examples of the connectors have been shown above, any type of connector having a structure that allows the connection between the heating element and the display tube to be released due to a change in the temperature of the heating element can be applied.

The present invention will be explained below with reference to the drawings.

Figure 1 shows an example in which the heating element consists of a nonflammable, thermally conductive container, a heating resistance wire and a heating agent housed in the container and electrically connected to the coil. When current flows from both ends of the coil to the heat generating resistance wire S of the heat generating element DA in the case 3 with a guide tube, the heat generating resistance wire S becomes red hot, the heating agent 6 burns, and the non-flammable container 7 is heated, causing the surface temperature to rise. rises. The heating resistance wire S is a platinum-iridium wire or a nichrome wire that becomes red hot due to the minute current induced in the coil L.
A diameter of ~25 microns is preferred. If it is smaller than 10 microns, the red heat energy will be small and it will be difficult to ignite the heating agent, and if it is larger than 25 microns, the minute current from the coil l may not cause it to become red hot. The heating agent 6 is
Optimum materials are those with good ignitability, such as barium chromate-boron type and copper oxide-aluminum type, which generate less gas during combustion and undergo redox reactions. Further, as the noncombustible container, a metal cylinder with good heat transfer, such as iron, aluminum, brass, etc., a ceramic cylinder, etc. can be used. When the surface temperature of the non-combustible container 7 rises, the connecting tool, that is, the linear body /θ that is fixed by wrapping the non-combustible container 7 and the latch 7 on the top surface of the display tube, melts or deforms, and the latch t The indicator tube slides down inside the guide tube λ and protrudes from the guide tube, indicating a failure. The linear body 10 may be a natural fiber thread such as cotton thread, woolen thread, etc., which melts and breaks depending on the surface temperature of the non-combustible container 70. 0-diameter, synthetic fiber yarn such as nylon, Tetron, etc.
2 to 1.0 m diameter, or synthetic resin strip such as nylon, Tetron, etc., 0.2 to 0.5 mm thick;
Widths of 1 to 5 fi can be used. Further, a thread-like or narrow strip-like material made of a shape memory alloy (for example, a nickel-titanium shape memory alloy) that has the property of returning to its original shape depending on temperature can also be used as the cotton material 7. The material of the guide tube, case 3, and display tube g is not particularly limited, but it is practically preferable to use synthetic resin. It is preferable to color them so that they can be easily spotted by aerial patrols. For example, it is preferable to color the guide and case 3 in white or yellow, and to color the display cylinder g in red.

FIG. 2 is a sectional view showing a state in which the flash indicator shown in FIG. 1 is activated and the display tube g has fallen, and the display tube g has protruded from the guide tube so that it can be easily found. If you want to reuse the flash indicator after it has been activated, remove the lid II of the case 3, replenish the worn parts of the heating element, such as heating agent, and slide the indicator tube upward in the guide tube, and then The display tube and the heating element may be fixed using a shaped body.

FIG. 6 shows a flash indicator of the present invention in which the heating element is a flash bulb, and its function is exactly the same as that of FIG. Also, connect both ends of the coil / to two electrodes /2,
The electrodes are coated with adhesive/3 to prevent deterioration due to rainwater, etc. Two terminals 15 of the flash bulb/4' are in contact with the electrodes. If a flashbulb is used as the heating element, replace the flashbulb with a new one after activation, and use the n shown in Figure 1 above.
The flash indicator can be easily reused by connecting the display tube and the flash bulb using the same process as the heating element.

Since the heating element reaches a considerably high temperature when the flasher is in operation, it is necessary to make contact with other members through a heat insulating material such as asbestos.

Next, the flashover indicator of the present invention was attached to a simulated lightning generator, and a high current was actually generated to confirm the effectiveness of the indicator.

Figure 4 is a schematic diagram of the simulated lightning generator. When a 1g capacitor is charged by the DC high voltage power generator /7 and the switch /9 is turned on, a high current is generated at the angle 20 of the simulated steel tower. The fault indicator / is activated. In addition, two resistors are inserted in the middle of the circuit to change the current waveform to iJ.
At the same time, the current waveform is recorded from both ends of the shunt resistor 23 using a synchroscope (not shown).

FIG. 5 shows an example of the current waveform generated in the above test, with the time taken to reach the maximum current set to 10 microseconds.

The following table shows the conditions for the simulated lightning test, the type of flash indicator, and the operating status.

Since the flash flash indicator of the present invention does not use explosives like conventional indicators, it is not subject to any legal regulations, has a simple structure, and operates correctly in the event of a lightning strike. It is also possible to easily know from a distance whether it has activated or not, and whether or not there has been a lightning strike. Once activated, there is no need to replace the display with a new one as in the past, and it is convenient for tasks such as replacing consumable parts in a short period of time, and can be reused immediately. A flash flash indicator is especially suitable when resource saving is strongly desired.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the structure of an example of the flash indicator of the present invention in which the heating element is a container containing a heating resistance wire and a heating agent, and FIG. 2 shows the flash indicator of FIG. FIG. 6 is a sectional view showing the structure of another example of the flash indicator of the present invention in which the heating element is a flash bulb. FIG. Figure 5 shows an example of the current waveform generated in the angle when tested using a simulated test device. l...coil, co...guide tube, 3...case,
DA...Heating element, 3...Heating resistance wire, 6...Heating agent, Ri...Nonflammable container, Z...Display tube, Ri...Latch,
10... Linear body, /l... Case lid, /lI...
・Flash ball. Patent applicant: NOF Corporation

Claims (2)

[Claims] (1) A coil in which a current is induced by a change in the magnetic field lines caused by a surge current caused by a lightning strike, a heating element electrically connected to the coil, and a heating element installed below the heating element so that the current induced in the coil generates heat. The guide tube has a built-in display tube that can be slid vertically, and the display tube and the heat generating element are connected by a coupling that can be disconnected due to a change in the temperature of the heat generating element and the display tube can be slid downward. Fraudulent flash indicator. (2) Claim 1 in which the heating element comprises a nonflammable, thermally conductive container, a heating resistance wire housed in the container and electrically connected to the coil, and a heating agent. Flash indicator as described. (3) The flash flash indicator according to claim 1, wherein the heating element is a flash bulb electrically connected to the coil.