JPH01287478A - Display device for ground-fault accident point survey - Google Patents

Abstract

PURPOSE:To prevent an excessive contact-pressing force from being applied to an end surface for coupling by applying a base body below a power distribution line, rotating a pressure body around a hinge part and covering the power distribution line with it, and coupling its free end with the base body by an engaging lever. CONSTITUTION:When a nut 26 is clamped, its movement by the clamping is limited to the position where the tip part of a main body 11 of the pressure body 10 abuts on a receiving seat 25. Consequently, the main body 11 of the pressure body 10 is prevented from moving toward the base body 4 excessively to press and crush an energizing spring 37. Further, when the pressure body 10 is open to the base body 4 when fitted to an electric conductor 95, a 2nd element 32 is held elastically by the energizing spring 37 even if leg parts 32a and 32b of the 2nd element 32 abuts on the power distribution line 95 and other foreign bodies, so the 2nd element is prevented from being broken with a large applied force.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is a method for detecting and displaying ground fault faults when an exploration signal current flows through the distribution line by being attached to the distribution line. Regarding a display device for point exploration.

[Conventional technology]

An annular core of a current transformer is attached to the distribution line in such a manner that the distribution line passes through it, and a detection coil is attached to the core, and a detection signal is obtained in the coil by causing a probe signal current to flow through the arrangement wire. There is a device that operates a display section using the detection signal.

However, since it is difficult to attach the annular core to the distribution line with the above structure, the present applicant filed Japanese Patent Application No. 62-206743 dated August 20, 1988 and August 2, 1988.
Japanese Patent Application No. 62-207476 dated 1982 discloses a detection section that is attached to a distribution line to detect the exploration signal current flowing through the distribution line and output a detection signal, and a detection section that outputs a detection signal by detecting the exploration signal current flowing through the distribution line. and a display section configured to operate the display when the power distribution line is received, and the detection section includes a base body and a presser body, which are positioned below and above the power distribution line, respectively, and the base body and the presser body. Two fasteners are provided on both sides of the distribution line storage space located between the two to tighten the presser bodies against the base, and the base has a space for the distribution line to be placed between the two. A U-shaped first element in the annular current transformer core for surrounding the periphery of the current transformer core is provided with its two connecting end faces facing upward, and
A detection coil is attached to the first element, and a second element in the shape of an inverted U in the annular current transformer core is attached to the presser body. An indicator for detecting a ground fault point is proposed in which the two connecting end surfaces of the two elements are in contact with the two connecting end surfaces of the first element.

[Problem to be solved by the invention]

However, with the above proposal, when performing installation work on live distribution lines, two fasteners must be tightened, which not only makes the work cumbersome, but also makes it difficult to tighten the fasteners on live distribution lines. When attempting to tighten a fastener on the opposite side of the operator's hand, the user must extend his/her wrist over the live power distribution line and reach the fastener on the opposite side. Therefore, there is a problem that is extremely dangerous.

Furthermore, if there is an imbalance in the tightening force of the two fasteners, one of the three connection end faces of the first and second elements that are in contact with each other will be pressed with a large force, and the other will have a gap. There is also the problem that the magnetic properties of the core may be disrupted.

Furthermore, if the clamping force of both wires is too strong, the tightening force will be applied to the above-mentioned end faces, and excessive pressure will be applied there, causing the problem that the first or second element will be damaged (chip). be.

The present invention has been made in view of the above points, and its purpose is to make the installation operation to the distribution line simple and safe, and to make the core exhibit predetermined magnetic characteristics in the installed state. Moreover, it is an object of the present invention to provide an indicator for detecting a ground fault point, which can also prevent unexpected damage to the core during installation.

[Means to solve problems]

In order to achieve the above object, the present invention takes the measures as described in the claims above, and its effects are as follows.

[Effect]

When attaching to a power distribution line, place the base body under the power distribution line, rotate the presser body around the hinge part to cover the power distribution line, and connect its free end to the base body with an engaging rod. do.

In the installation state performed in this way, the two connecting end surfaces of the second element are opposite to the two connecting end surfaces of the first element.
Both can be elastically pressed with appropriate pressure.

〔Example〕

The drawings showing the embodiments of the present application will be described below.

In the display shown in FIGS. 1 and 2, numeral 1 denotes a case, which is made of a metal material, such as an aluminum alloy, and has a shape that is open at the bottom. 2 is a detection unit provided on the upper part of the case 1, 3 is a display unit, and a drive circuit 3 provided in the case 1.
a and a display device 3b attached to the lower side of the case 1.

In the detection unit 2, 4 indicates a base body, and the case l
It consists of the upper part. Reference numeral 6 indicates a wire receiving portion formed to bulge upward in the base body 4, and reference numerals 7a and 7b indicate connecting pieces, respectively.

Next, reference numeral 10 indicates a presser body in the detection unit 2, and 11 is a main body of the presser body 10, which is formed by press-forming a metal plate into a U-shaped cross section as shown in FIGS. . In FIG. 3, reference numeral 12 indicates a bolt insertion hole formed at one end of the main body 11, 13 indicates an inlet, and 14 indicates a stopper. Next, reference numeral 15 denotes a mounting seat provided in the middle part of the main body 11, which is formed to project from the left and right as shown in FIG. 3.4.

Reference numeral 16 denotes a support body attached to the seat portion 15, which is made of polyethylene. Reference numeral 17 denotes a wire holder attached to the support body 16, which is made of an elastic rubber material, and has a recessed portion 18 on its lower surface for applying to the wire.

Next, two fasteners provided on both sides of the distribution line installation space 20 between the base body 4 and the presser body 10 in order to tighten the presser body IO to the base body 4 will be explained. Reference numeral 21 indicates one of the fasteners, which is composed of a hinge. This butterfly fitting 2
1 is a shaft pin, which allows the presser l
0th order 22 in which O is hinged to the base 4 so that it can be opened and closed.
1 indicates the other fastener, which is composed of an engaging rod whose negative end is connected to the base body 4 and whose other end is engaged with the presser body 10. In this fastener 22, 23 is a bolt, one end of which is pivoted to the connecting piece 7b with a shaft 24 as shown in FIG. 1.2. Reference numeral 25 denotes a seat formed in the middle part of the bolt 23, which is shaped like a flange as shown in the figure.

Reference numeral 26 indicates a tightening nut screwed onto the bolt 23.

Next, 28 is a current transformer for current detection in the detection unit 2, in which 30 is a current transformer core formed in an annular shape surrounding the distribution line installation space 20. The core 30 is made of ferrite. The core 30 is composed of a first element 31 in the shape of a 0 and a second element 32 in the shape of an inverted U. In the first element 31, 31a, 3
Reference numerals 1b and 31c respectively indicate leg portions and a connecting portion connecting the two leg portions, which are fixed to the base body 4. 31a', 31b'
respectively indicate the connecting end surfaces, and in the second element 32,
32a and 32b are leg parts, and 32c is a connecting part, which has a semicylindrical cross section as shown in FIG. is a curved surface. 32a', 32
b' indicates a connecting end surface.

Next, the attachment structure of the second element 32 to the presser body IO will be explained with reference to FIG. 1.4. 36 is a receiving member formed integrally with the support plate 16, and the upper surface thereof has a 7-shaped recess 36a.
By not fitting the lower surface 32c'' of the connecting portion 32C of the second element 32 therein,
The second element 32 is configured so that the tips of both legs can move 111 times in a direction perpendicular to a plane including both legs (horizontal direction in FIG. 4) about the base of the second element 32, that is, the connecting part 32C. be. The horizontal dimensions of the receiving member 36 in FIG. 1 are as follows:
The leg portions 32a, 32b of the second element 32 are formed to have substantially the same dimensions or to be slightly shorter than each other, so that the second element 32 can be positioned in the left-right direction in FIG. 1.

Reference numeral 37 denotes biasing springs, two #37a as shown in FIG.

A torsion coil spring 37b is used, one leg 37b of which is attached to the main body 11 of the presser foot 10 with a stop 38.
The other Mi 37a elastically abuts on the upper surface 320' of the second element 32 at the middle part of the leg in the direction in which it can tilt (the left-right direction in FIG. 4), and the second Mi 37a The element 32 is biased toward the base body 4. With such a configuration, the second element 32 can elastically move back and forth toward the base 4, and can be moved forward by the receiving member 3.
Uke is stopped at 6.

A guide member 40 is provided around the end surfaces 32a' and 32b' at the tips of the legs 32a and 32b of the second element 32, and is made of a synthetic resin material, and its inner surface is tapered as shown in FIG. It is a shaped guide surface 40a, and is attached to the legs 32a and 32b with an adhesive 40b. This guide member 40 may be provided on the leg portion of the first element 31 instead of the second element 32.

Next, reference numeral 42 shown in FIG. 1 indicates a coil assembly attached to the second element 28, which is composed of a coil case 43 and a detection coil 58 provided within the case 43. 6
A coil cover 1 is placed over the coil assembly 42 to protect the coil assembly 42 from rainwater. This cover also covers the top surface of the case l to prevent rainwater from directly splashing there.

Next, the display section 3 will be explained. The drive circuit 3a
is constructed by attaching well-known circuit elements to a printed circuit board, and is attached to a mounting frame (not shown) fixed to the case l. Reference numeral 71 denotes a drive body in the display device 3b, which has a rotating wheel for driving the display body, although not shown, and is attached to the above-mentioned mounting frame. Reference numeral 72 denotes a display body, which is attached to the rotating wheel of the drive body 71. This display body 72 is formed into a cup shape, and its lower surface and peripheral side surfaces are painted differently into a white portion 72a and a black portion 72b, as shown in FIG. Reference numeral 73 denotes a cover for the display device, which is made of a transparent material, and is attached to the case 1 with a fastening ring 74.
It is fixed to . 75 indicates a watertight O-ring.

A shielding frame 80 serves to shield the display 72 from a part of the cover 73, and is black in color, with windows 81 and 82 formed on the side and bottom surfaces, respectively.

Next, the attachment of the display having the above configuration to the high voltage distribution line 95 will be explained. As shown in FIG. 2, with the holding body 10 open to the base 4,
5, a presser body 10 that applies the base 4 from the bottom side thereof
is placed over the distribution line 95. This operation can be easily carried out by slightly pushing up the presser foot 10 in the direction of arrow 96 in FIG. When the presser body 10 is placed over the power distribution line 95 in this way, the guide member 4
With the tapered guide surface 40a at 0, the connecting end surfaces 32a'' and 32b'' of the second element 32 are properly positioned with respect to the connecting end surfaces 31a' and 31b' of the first element 31, and the end surfaces 31a'' and 32a ' and end surfaces 31b' and 32b' overlap each other tightly without any displacement. Raise the bolt 23 as shown by arrow 97 in FIG. 2 and position it in the insertion hole 12 through the introduction port 13. After that, the Nand 26 is tightened and the presser body 10 is sequentially moved to the side of the base body 4, and the distribution line 95 is connected to the distribution line mounting portion on the top surface of the wire receiving portion 6 and the wire presser 17 through the cover 61.
and the contact portion 18 in the state. In this case, even if the main body 11 of the presser lO moves toward the base 4, the second element 32 whose end face is already in contact with the first element 31 as described above does not move in the same direction, but is attached. Only the force spring 37 is bent. In the subordinate lever state, the second element 32 is pressed against the first element 31 by the urging force of the urging spring 37. As a result of the above, the second element 3
As shown in FIG. 1, a gap is created between the lower surface 32c'' of the connecting portion of No. 2 and the receiving member 36.

When tightening the nut 26 as described above, movement due to the tightening is limited to a position where the tip of the main body 11 of the presser 10 comes into contact with the seat 25.

This can prevent the main body 11 of the presser lO from moving excessively toward the base 4 and causing the biasing spring 37 to be crushed (incapable of exhibiting its elasticity).

Further, when attaching to the electric wire 95 as described above, when the presser body 10 is in an open state with respect to the base body 4 as shown in FIG. Even if the second element 32 is hit by a foreign object, the second element 32 is elastically held by the biasing spring 37, so the second element 32 can be tilted as shown by the imaginary line in FIG. This prevents it from being damaged by applying a large force to it.

Next, the operation of the display device having the above configuration will be explained. The above installation is in high voltage power distribution condition! When the exploration signal current flows through 95,
The resulting magnetic flux is generated in the core 30.

The magnetic flux is detected by the detection coil 58, and the detection signal is transmitted to the drive circuit 3a. Then, the drive circuit 3a outputs a drive signal, which is applied to the drive body 71 of the display device 3b. Then, the driving body 71 rotationally drives the display body 72.

As a result, the display 72 is previously in its normal position relative to the cover 73 as shown in FIG.
As shown in FIG. 10, the black portion 72b is positioned in the display position relative to the cover 73, and the white portion 72a is positioned in the window 81.82.

That is, until then, the display device 3b appeared to be completely black as shown in FIG. 9, but by changing the position of the display body 72, the display color changed to white inside the black part as shown in FIG. becomes visible. The above-mentioned display device performs the same operation as described above when a short-circuit current flows through the high-voltage power distribution line 95, and when a return signal current flows through the high-voltage power distribution line 95, the display body 72 performs a return operation. There is.

〔Effect of the invention〕

As described above, in the present invention, when the detection unit 2 is attached to the power distribution line 95 so that the current transformer core 30 surrounds the power distribution NIA 95, the exploration signal tl flowing through the power distribution line 95 is
Of course, it is possible to detect the current and operate the display unit 3 using the detection signal, and when the detection unit 2 is attached to the wire 95 in a live wire state, it is possible to tighten the fasteners. Since the operation only needs to be performed on one side of the fastener 22, the work is extremely simple and safe (as in the prior art, the user simply moves his/her wrist over the power distribution line and operates the fastener on the opposite side). This has the effect of eliminating the need for such dangerous work.

Moreover, even when tightening is performed by only one operation as described above, in the tightened state, the connecting end surfaces 32a' and 32b' of the second element 32 in the current transformer core 30 are the connecting end surfaces of the first element 31. 31a' and 31b', so that the first. The two connecting end surfaces of the second elements 31 and 32 (the connecting end surfaces 31a° and 32a'' and the connecting end surfaces 31b° and 32b') are brought into substantially equal pressure contact to exhibit the planned magnetic properties. It has the effect of

Furthermore, in the case of the tightening operation, even if the force is strong, the connection end surfaces 31a', 31b', 32a', 32b
The elasticity prevents an excessive pressing force from being applied to the element, and has the effect of preventing the element from chipping due to over-tightening as in the prior art.

Furthermore, in the case of attachment to the power distribution line 95 as described above, the presser body 10 can be rotated around its hinge to attach the second
When the connecting end surfaces 32a' and 32b' of the element 32 are brought into contact with the connecting end surfaces 31a' and 31b' of the first element 31, there is a play in the hinge, and the presser body 10 is moved as shown in FIG. Even if it is in a tilted state, the second element 32, which is pushed only at the middle part in the direction in which it can tilt, will be lightly tilted as shown in FIG. 6 when the guide member 40 comes into contact with the first element 31. The orientation can be changed to match the first element 31, and as a result, the second element 32
The connecting end surface 32a'' at.

32b° is the connecting end surface 31a' of the first element 31,
There is also the effect that it can be polymerized tightly to 31b' to exhibit the predetermined magnetic properties as described above.

[Brief explanation of the drawing]

The drawings show an embodiment of the present application, and Fig. 1 is a partially cutaway front view of an indicator for detecting ground fault points, Fig. 2 is a front view to explain how it is attached to electric wires, and Fig. 3 is a presser foot. top view of the body,
Fig. 4 is a sectional view taken along the line IV-IV, Fig. 5.6 is a schematic sectional view illustrating the state of the current transformer core in the process of placing the presser over the distribution line, and Fig. 7 is a perspective view of the biasing spring. 8 is an exploded perspective view of the display device, FIG. 9 is a perspective view of the display device in a normal state, and FIG. 10 is a perspective view of the display device in a display state. 2...Detection section, 3...Display section, 4...Base, 10
... Presser body, 30... Core of current transformer, 31... First element, 32... Second element, 37... Biasing spring. Figure 1 Figure 2 1/'1 Figure 3 ■ Figure 4 Figure 5 Figure 8 Figure 9 Figure 10

Claims (1)

[Claims] 1. A detection section that is attached to a distribution line to detect the exploration signal current flowing through the distribution line and output a detection signal, and a display section that operates to display in response to the detection signal. The detection unit has a base body and a holding body positioned below and above the power distribution line, respectively, and a space in which the power distribution line is placed between the base body and the holddown body. It has two fasteners on both sides of the body for tightening the presser body against the base body, and the base body is equipped with an annular current transformer for surrounding the space where the distribution line is placed. The U-shaped first element in the core is
The first element is provided with the two connecting end faces facing upward, and the first element is provided with a detection coil, while the holding body is provided with an inverted U in the annular current transformer core. The second element having a letter shape is provided so that the two connecting end surfaces of the second element come into contact with the two connecting end surfaces of the first element due to the fastening of the presser body to the base body. In the display for fault point detection,
One of the fasteners is configured with a hinge that hinges the presser body to the base so that it can be opened and closed, and the other has one end connected to the base and the other end that engages the presser body. Further, the state of attachment of the second element to the presser body is such that the second element can freely move forward and backward toward the base body with respect to the presser body, and the second element is attached to the presser body so that the second element is attached to the presser body. The tip of both legs is configured to be able to tilt in a direction perpendicular to a plane including both legs about the base part, and the back of the second element is on the opposite side from the connecting end surface. In this case, a second
A biasing spring that biases the element toward the base body is elastically abutted, and the connecting end surface of the second element or the first element is further provided with a biasing spring that biases the element toward the base body. An indicator for detecting a ground fault point, which is provided with a guide member that guides the second element to a state where the connecting end surface of the second element overlaps the connecting end surface.