JPH0229675Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention is attached to the tip of an arcing horn, and when the arcing horn is struck by lightning on a power transmission line or distribution line and the arcing horn flashes, the device will fly out from the arcing horn and fall off. This invention relates to a flashover indicator that indicates a flashover location.

Conventional technology Generally, when a power line such as a power transmission line or distribution line is struck by lightning, the arcing horns installed as electrical weak points first cause a flashover, which subsequently forms a discharge path for alternating current, which then becomes a follow-on current. The arc discharge continues. Under normal natural conditions, this follow-on current continues uninterrupted and is accompanied by an arc, which can cause damage to insulators, power equipment, household electrical equipment, and even personal accidents. For this reason, power plants immediately open circuit breakers to cut off the following flow.

However, even in this case, the aforementioned insulators, etc. are expected to be damaged due to abnormal phenomena associated with the following current, resulting in a decline in insulation performance. This will inevitably result in a power outage, causing a great deal of trouble and damage to electricity consumers. Therefore, a flashback indicator was proposed as Japanese Patent Application No. 50-92185 (published in Japanese Patent Publication No. 57-16449) for the purpose of visually confirming flashback locations caused by lightning strikes from the ground. The proposed sparkling indicator has a structure as shown in Fig. 4, in which a small hole 42 is drilled through the center of the bottom of an insulating bottomed cylinder 41 made of synthetic resin, and a bottomed cylinder 41 is made of synthetic resin. There is a stepped portion 4 approximately in the center of the body 41.
3 and 44, the diameter of the cylinder gradually becomes thicker toward the opening of the cylinder, and the bottomed cylinder 4
A valve plate 45 having a diameter slightly smaller than the inner diameter is mounted inside the stepped portion 43 of No. 1, and a spherical indicator 46 is integrally secured to the outer periphery of the bottomed cylinder 41. If a flashover indicator with such a configuration is inserted and attached to the tip of the arc horn 47 connected to a suspension insulator, etc., when a power transmission line is struck by lightning, there will be no damage between the arc horn 47 and the other opposing arc horn. Electric discharge is generated, and a discharge path is formed from the small hole 42 at the center of the bottom of the bottomed cylinder 41 to the tip of the arc horn 47 through the small gap 48 between the outer periphery of the valve plate 45 and the inner surface of the stepped portion 43 . At this time, the area around the air path generates high heat due to the instantaneous large current, and the air in the air chamber 49 formed between the tip of the arc horn 47 and the bottom of the bottomed cylinder 41 is rapidly heated. The bottomed cylinder 41 is ejected from the arc horn 47 with the indicator 46 attached thereto due to the expansion pressure. Therefore, by visually recognizing the missing arc horn with the naked eye or binoculars, the location of the flashover can be easily identified from the ground.

Furthermore, a so-called follow-on flow cutoff type sparkling indicator, in which the air chamber 49 is filled with an arc extinguishing agent or the like to block follow-on flow, is also disclosed in Japanese Utility Model Publication No. 57-10074.
However, although these have a step part whose diameter is slightly enlarged on the outer peripheral surface of the insulating cylinder holding part,
These steps were simply formed for the convenience of holding the insulated arc extinguishing cylinder and attaching it to the arc horn.
It is not possible to generate enough air resistance to shorten the flight distance of the flashover indicator.

Problems to be Solved by the Invention The above-mentioned conventional flashover indicator is extremely effective in that it can reliably indicate the flashover location. However, if the indicator flies out from the arc horn due to a lightning strike and separates, the flight distance will be quite large (for example, about 27 to 37 meters), which is not a problem in mountainous areas with no human habitation, but when used in urban areas. It cannot be said that it is sufficient in terms of safety for the surrounding area.

The present invention was developed in view of the above circumstances, and as a result of various experiments, it was found that when the indicator jumps out from the arc horn due to arc energy and falls off, the shape and material of the indicator attached to the outside of the bottomed cylinder It was confirmed that the flying distance and falling speed were significantly reduced. This invention is based on these experimental facts,
To provide a spill indicator with a deceleration plate that can reliably indicate a spill point as in the past, and can be used safely even in urban areas by reducing flying distance and falling speed.

Means for Solving the Problems The present invention, as stated in the claims of the utility model registration, is a horn insertion tube into which an arcing horn is closely inserted, by connecting a half of a bottomed cylinder made of an insulating material such as synthetic resin to a horn insertion tube into which an arc horn is tightly inserted. The other half is a small diameter cylindrical part constituting an air chamber or an arc extinguishing agent chamber, and the boundary step between the horn insertion cylindrical part and the small diameter cylindrical part has a diameter slightly larger than the inner diameter of the horn insertion cylindrical part. In addition to carrying a small-diameter valve plate, a micro-diameter hole passing through the inside and outside is bored in the center of the bottom of the small-diameter cylinder, and a flexible material such as cross-linked polyethylene foam is placed at an appropriate position on the outer circumference of the bottomed cylinder. A disc-shaped indicator body made of a synthetic resin material that is heat resistant and has a required thickness and a diameter at least twice the maximum outer diameter of the bottomed cylinder is extended outward in the radial direction. By fixing them together, the above problem is solved.

Function The inventive flashover indicator with the above configuration has flexibility and heat resistance attached to the outer periphery of the bottomed cylinder when an arc is generated by a lightning strike and the flashover indicator jumps out from the tip of the arc horn. The disc-shaped sign is
It deforms in the opposite direction due to air pressure for a short time, but due to its flexibility and heat resistance, it immediately returns to its original shape and flies down, and its diameter is at least twice the diameter of the maximum outer diameter of the bottomed cylinder. Since the ball extends outward in the radial direction, it increases air resistance and reduces flight distance and fall speed. Therefore, the flashover point can be marked reliably, and the flight distance and falling speed can be reduced, so it can be used safely even in urban areas.

Embodiment An embodiment of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 is a bottomed cylinder made of an insulating material such as synthetic resin, and the left half of the cylinder 1 (in the illustrated arrangement) is The horn insertion cylinder part 2 is used to closely insert the arc horn, and the right half (in the arrangement shown) is a small diameter cylinder part 3 that constitutes an air chamber or an arc extinguishing agent chamber. A valve plate 5 having a diameter slightly smaller than the inner diameter of the horn insertion cylinder part 2 is mounted on the boundary step 4 with the small diameter cylinder part 3, and a valve plate 5 which penetrates inside and outside is mounted in the center of the bottom part 6 at the outer end of the small diameter cylinder part 3. Small diameter hole 7
Further, a recessed groove 7' is formed at an appropriate position on the outer periphery of the bottomed cylinder 1, that is, in the illustrated example, at a substantially central position on the outer periphery of the horn insertion cylinder part 2, and the recessed groove 7'
The required thickness of the synthetic resin material having both flexibility and heat resistance, such as cross-linked polyethylene foam, as shown in FIG. A disc-shaped indicator 8 having a diameter approximately twice that of the other is fitted and locked, protruding outward in the radial direction, and fixed together.

FIG. 3 shows the state in which the deceleration plate-equipped spillover indicator of the present invention constructed in this way is used.
In the figure, 9 is a power line conductor, 10 is an arc horn directly connected to the power line, and 12 is an opposite arc horn directly connected to a ground conductor 13.

Now, when the lightning surge charge discharges between the arc horns 10 and 12 and forms a discharge path 14, the bottomed cylinder 1
The air in the small diameter cylinder 3 is rapidly heated by the arc energy and expands instantaneously, and due to the expansion pressure, the bottomed cylinder 1 and the disc-shaped indicator 8 are integrated into one body, and the arc horn 10 Jump out. Unlike conventional rigid spherical signs, the flexible disc-shaped sign 8 deforms in the opposite direction due to air pressure for a short time after being ejected, but immediately returns to its original shape. Moreover, the flight speed is reduced due to air resistance due to the fact that the diameter is at least twice as large as the maximum outer diameter portion 11 of the bottomed cylinder 1 and extends outward in the radial direction. Flight distance and falling speed are reduced.

Since the diameter of the maximum outer diameter portion of the bottomed cylinder 1 of this kind of known sparkling indicator is around 40 mm, this sparkling indicator is made of cross-linked polyethylene foam with a thickness of 5 mm, and the maximum outer diameter is approximately 40 mm. When a disk-shaped indicator with a diameter three times that of
It was about 11m. On the other hand, the aforementioned special public
When the same electric shock test was carried out with a spherical indicator having a diameter of 100 mm attached to the flashover indicators having the configurations shown in Publication No. 16449 and Publication No. 10074 of 1980, the above-mentioned one-wire ground fault current was 0.2. With KA, it was about 27 to 37 meters, and with this invention, the flight distance was reduced to about 1/3.

Furthermore, due to the arc heat during the electric shock, the disc-shaped indicator only partially discolored, and no plastic deformation occurred.

The above-mentioned tendency to decrease flight distance is manifested significantly when the diameter of the disc-shaped indicator is about twice or more the diameter of the maximum outer diameter of the bottomed cylinder, as shown in the figure.

Effects of the invention As explained above, according to the invention, when a lightning surge causes a flashover between the arc horns, the bottomed cylinder and the disc-shaped indicator unit fly out from the arc horn and fall. However, the disc-shaped indicator has a diameter that is at least twice as large as the maximum outer diameter of the bottomed cylinder and extends outward in the radial direction, and is both heat resistant and flexible. Because of this, it will not be thermally deformed even if it is affected by arc heat during electric shock, and due to air resistance during flight, the flight distance can be shortened compared to conventional ones, and the falling speed can be slowed down, so it can be used in urban areas. It can also be used in other areas, and has the excellent effect of being able to easily identify the location of the tangle with the naked eye or with binoculars or the like.

Furthermore, it is more effective if the disc-shaped indicator is colored in an easy-to-identify manner, and the color is changed depending on the year of installation, or if the color is the same color and the number of the year of installation is added.

[Brief explanation of drawings]

Fig. 1 is a sectional view of one embodiment of the deceleration plate-equipped spillover indicator according to the present invention, Fig. 2 a and b are structural examples of a disc-shaped indicator, and Fig. 3 is an explanation of how to use the inventive indicator. FIG. 4 is a sectional view showing an example of the structure of a conventional flashover indicator. 1: Bottomed cylinder, 2: Horn insertion cylinder, 3: Small diameter cylinder, 4: Boundary step, 5: Valve plate, 6: Bottom, 7:
Microdiameter hole, 8: disk-shaped indicator, 10, 12: arc horn, 11: maximum outer diameter portion, 14: discharge path.

Claims (1)

[Scope of utility model registration request] One half of the bottomed cylinder made of insulating material such as synthetic resin serves as the horn insertion tube into which the arc horn is tightly inserted, and the other half serves as the small diameter tube that constitutes the air chamber or arc extinguisher chamber. , a valve plate having a diameter slightly smaller than the inner diameter of the horn insertion tube is mounted on the boundary step between the horn insertion tube and the small diameter tube, and a small diameter hole is formed in the center of the bottom of the small diameter tube to penetrate inside and outside. A required thickness of a synthetic resin material having flexibility and heat resistance such as cross-linked polyethylene foam is provided at appropriate positions on the outer circumference of the bottomed cylinder, and the maximum outer diameter of the bottomed cylinder is 1. A spillover indicator with a deceleration plate, characterized in that a disc-shaped indicator with a diameter at least twice the outer diameter extends outward in the radial direction and is fixed integrally.