JP2009069060A - Overcurrent passage indicator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an overcurrent passage indicator which prevents an effect of magnetic fields generated by pieces of electric wire of the other phases. <P>SOLUTION: The overcurrent passage indicator 1 is attached in a hung down state holding a piece of electric wire 2 between, detects a current flowing in the electric wire 2, and when an overcurrent flows, an indicator 25 reverses from a normality indicating state to an abnormality indicating state with rotating shafts 24a, 24b serving as the centers of rotation. The overcurrent passage indicator 1 includes magnetic rotating elements 26a, 26b fixed on both sides of the rotating shafts 24a, 24b of the indicator 25, and electromagnets 27a, 27b provided so that they face the magnetic rotating elements 26a, 26b and their central axis becomes parallel to the axial direction of the electric wire 2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an overcurrent passage indicator.

  The overcurrent passage indicator is supported in a suspended state on wires such as distribution lines, so that when an overcurrent flows through the wire due to an accident such as a ground fault or short circuit, it is promptly displayed. (For example, refer to Patent Document 1).

In the overcurrent passage indicator described in Patent Document 1, a detection unit including a core and a coil is disposed so as to surround the electric wire, and a current flowing through the electric wire is detected by the detection unit. In addition, a display unit is disposed adjacent to the detection unit, and the display unit is provided with a display body and driving means including an electromagnet and a magnetic rotating element for driving the display body. When an overcurrent flows through the electric wire, a detection signal is output from the detection unit, and the driving means is operated by the detection signal, so that the display body is inverted from the normal state to the abnormal display state.
JP-A-11-142443

  By the way, as shown in FIG. 8, the overcurrent passage indicator described above includes the U-phase 102 u and the W-phase 102 w at both ends of the three-phase wires of the U-phase 102 u, the V-phase 102 v and the W-phase 102 w from the left. It was used to detect the faulty part of the distribution line. However, as shown in FIG. 9, the overcurrent passage indicator 101 is attached to all the three-phase wires of the U-phase 102u, the V-phase 102v, and the W-phase 102w from the left, and the failure location of the distribution line is detected. It can be used to discover phases.

  Thus, when the overcurrent passing indicator 101 is attached to all the three-phase electric wires 102u, 102v, and 102w, for example, if the U-phase 102u and the W-phase 102w at both ends are short-circuited, the U-phase 102u and the W-phase 102w A short-circuit current larger than the normal current value flows through. That is, an overcurrent in the back direction of the paper flows in the U phase 102u, and an overcurrent in the front direction of the paper flows in the W phase 102w. Then, a magnetic field as indicated by a broken line in the figure is generated in the U phase 102u and the W phase 102w. As shown in FIG. 9, an external magnetic field from the upper side to the lower side passes through the overcurrent passing indicator 101 attached to the V phase 102v. Therefore, the electromagnet 127 constituting the driving means for driving the display 125 in the overcurrent passage display 101 is attached to the V-phase 102v because the electromagnet 127 differs in the direction of the magnetic field passing through the core 128 from the bottom to the top. There is a possibility that the magnetic rotating element 126 of the overcurrent passing indicator 101 may be rotated or become unstable. Further, the overcurrent passage indicator 101 attached to the U phase 102u and the W phase 102w is not limited to the central V phase 102v, but is not as large as the overcurrent passage indicator 101 attached to the V phase 102v. The influence of the magnetic field due to the electric wire is considered.

  Therefore, in the overcurrent passage indicator described in Patent Document 1, a magnetic field made of a metal material such as a silicon steel plate is attached to the lower surface of the mounting plate on which the support member 123 to which the electromagnet 127 is fixed is attached so as to surround the electromagnet 127. A shielding plate is attached. However, the magnetic field shielding plate attached in this way is effective because it can shield the external magnetic field from the lateral method and oblique direction, but cannot shield the external magnetic field from the upper side to the lower side. In addition, when the magnetic field shielding plate is attached, the number of parts and work man-hours increase, resulting in an increase in cost.

For this reason, an overcurrent passage indicator in which the influence of the magnetic field due to the wires of the other phase is prevented has been demanded.
The present invention has been made in view of such circumstances, and an object of the present invention is to provide an overcurrent passing indicator in which the influence of a magnetic field by an electric wire of another phase is prevented.

Hereinafter, means for achieving the above-described object and its operation and effects will be described.
The invention according to claim 1 is attached in a suspended state with the distribution line sandwiched therebetween, detects the current flowing through the distribution line, and displays the abnormality from the normal display state to the abnormal state by the driving means when an overcurrent occurs. In the overcurrent passing indicator which is reversed to the state around the rotation axis, the driving means includes a magnetic rotation element fixed to at least one of both sides of the rotation axis of the display body, and the magnetic rotation element And an electromagnet provided so that its central axis is parallel to the axial direction of the distribution line.

  According to this configuration, the driving means is configured to be fixed to at least one of both sides of the rotating shaft provided on the display body, and to face the magnetic rotating element and to be parallel to the axial direction of the electric wire. An electromagnet provided. Therefore, even if a magnetic field is generated by an electric wire of another phase when an overcurrent flows in the electric wire of another phase different from the attached electric wire, the direction of the same magnetic field and the direction of the magnetic field of the electromagnet are substantially perpendicular, which affects the influence. I do not receive it. As a result, it is possible to prevent the influence of the magnetic field due to the wires of the other phase.

  When magnetic rotating elements are provided on both sides of the rotating shaft of the display body, the electromagnet can be arranged as follows. As described in claim 2, they are arranged in parallel and facing the same direction. Further, as described in claim 3, they are arranged in parallel while facing the opposite direction.

  ADVANTAGE OF THE INVENTION According to this invention, in the overcurrent passage indicator, the influence of the magnetic field by the electric wire of another phase can be prevented.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the overcurrent passage indicator 1 is attached in a suspended state to an electric wire 2 such as a distribution line, and a detection unit 10 that detects a current flowing through the electric wire 2 and an overcurrent is detected in the electric wire 2. And a display unit 20 for displaying the information when it flows.

The detection unit 10 includes a core, a coil, and the like, is disposed so as to surround the electric wire 2, and is clamped and fixed with bolts and nuts while the electric wire 2 is sandwiched.
The display unit 20 is attached to the lower part of the detection unit 10. A case 21 as a casing of the display unit 20 is formed in a cylindrical shape from a synthetic resin, and a transparent cover 30 is attached to the lower part thereof.

  A mounting plate 22 is disposed in the case 21, and a pair of support members 23a and 23b made of synthetic resin are mounted on the left and right sides of the lower surface thereof. A substrate is disposed on the upper surface of the mounting plate 22, and a control circuit including a detection control unit is mounted on the substrate.

  The display body 25 is formed in a disc shape from a synthetic resin. The display body 25 is orthogonal to the extending direction of the electric wire 2 with the rotating shafts 24a and 24b inserted into the bearing holes of the support members 23a and 23b at both ends. It is supported rotatably about a horizontal axis extending in the direction. Further, the outer surface of the display body 25 is divided into two parts, a normal display part 25a and an abnormal display part 25b. During normal power transmission, the white normal display portion 25a is arranged on the lower side, and the red abnormality display portion 25b is arranged on the upper side.

  As shown by the arrow A in FIG. 1 shown in FIG. 2, the right electromagnet 27 a and the left electromagnet 27 b are parallel to the axial direction of the electric wire 2 in both the support members 23 a and 23 b. Further, they are respectively arranged behind the central axis of the display body 25. The right electromagnet 27a includes a right core 28a and a right coil 29a. The left electromagnet 27b includes a left core 28b and a left coil 29b. Both electromagnets 27a and 27b are of a magnetic holding type, and once current flows through the coils 29a and 29b and magnetic poles in the front-rear direction are generated in the cores 28a and 28b, energization of the coils 29a and 29b is stopped. Even later, the magnetic poles of the cores 28a and 28b are held. In the present embodiment, during normal power transmission, the front side of the right core 28a is set to the S pole and the rear side is set to the N pole, and the front side of the left core 28b is set to the S pole and the rear side is set to N. It is set to be the magnetic pole of the pole. In addition, when the passage of overcurrent is detected, the right coil 29a is excited, the front side of the right core 28a is converted to the N pole, and the rear side is changed to the S pole, and the left coil 29b is excited and the left core 28b is excited. The front side is converted to a magnetic pole of N pole and the rear side is changed to S pole. That is, the electromagnets 27a and 27b are set so that the magnetic poles are the same on the left and right sides.

  As shown in FIG. 1, the right magnetic rotating element 26a is fixed to the rotating shafts 24a and 24b on both sides of the display body 25 so as to be close to and opposed to the right core 28a of the right electromagnet 27a, and the left electromagnet 27b. The left magnetic rotating element 26b is fixed so as to face and face the left core 28b. As shown in FIG. 3, a pair of semicircular arc magnet layers having different polarities are formed on the outer periphery of the magnetic rotating element 26a (26b). In the present embodiment, as shown in FIG. 1, driving as driving means for inverting the display body 25 from the normal display state to the abnormal display state by the electromagnets 27a and 27b and the magnetic rotating elements 26a and 26b. The part is composed.

  That is, during normal power transmission, the right magnetic rotating element 26a attracted to the front S pole of the right core 28a of the right electromagnet 27a is set to a position with the N pole magnet layer as the rear side, and the left electromagnet 27b. The left magnetic rotating element 26b attracted to the front S pole of the left core 28b is set at a position where the N pole magnet layer is the rear side. Thereby, the white normal display part 25a on the display body 25 is arrange | positioned in the lower position exposed to the transparent cover 30 side.

  On the other hand, when an overcurrent exceeding a predetermined value is detected due to a short circuit or the like, the right coil 29a of the right electromagnet 27a is excited and the front side of the right core 28a is changed to the N pole and the rear side is changed to the S pole. The N-pole magnet layer of the element 26a repels the front magnetic pole of the right core 28a, and a rotational force is induced in the right magnetic rotating element 26a. Also, the left coil 29b of the left electromagnet 27b is excited, the front side of the left core 28b is converted to the N pole and the rear side is changed to the S pole, and the N pole magnet layer of the left magnetic rotating element 26b is the front side of the left core 28b. A repulsive force is induced in the left magnetic rotating element 26b in a repulsive manner with respect to the magnetic pole. As a result, the magnetic rotating elements 26a and 26b and the display body 25 are rotated so that the S pole magnet layer of the right magnetic rotating element 26a is disposed on the rear side, and the S pole magnet layer of the left magnetic rotating element 26b is Arranged on the rear side. That is, the right magnetic rotating element 26a attracted to the front north pole of the right core 28a of the right electromagnet 27a is held at a position with the south pole magnet layer as the rear side, and the left core of the left electromagnet 27b. The left magnetic rotating element 26b attracted to the front N pole 28b is held at a position where the S pole magnet layer is the rear side. Therefore, the red abnormality display part 25b on the display body 25 is arranged in a state exposed to the transparent cover 30 side.

  Next, the operation of the overcurrent passage indicator 1 configured as described above will be specifically described. As shown in FIG. 4, the overcurrent passing indicator 1 is attached in a suspended state to all three-phase electric wires of the U phase 2u, the V phase 2v, and the W phase 2w from the left. During normal power transmission, as shown in FIG. 2, the N pole of the right magnetic rotating element 26a and the S pole of the right electromagnet 27a attract each other, and the N pole of the left magnetic rotating element 26b and the S pole of the left electromagnet 27b. Are in a state of being sucked. For this reason, the white normal display part 25a on the display body 25 is held in the state exposed to the transparent cover 30 side, and the normal state is displayed.

  Here, as shown in FIG. 4, when an overcurrent exceeding a predetermined value flows in the U phase 2u and the W phase 2w due to a short circuit or the like, a magnetic field is generated around the U phase 2u and the W phase 2w. In the drawing, an overcurrent in the U direction 2u flows in the rear direction (rear side) of the paper surface, and an overcurrent in the W phase 2w flows in the front direction of the paper surface (front side). A clockwise magnetic field is generated by the overcurrent flowing through the U phase 2u, and a magnetic field from the top to the bottom passes through the overcurrent passing indicator 1 attached to the V phase 2v. Further, a counterclockwise magnetic field is generated by the overcurrent flowing in the W phase 2w, and an external magnetic field from the upper side to the lower side passes through the overcurrent passing indicator 1 attached to the V phase 2v. Therefore, as shown in FIG. 5, the magnetic field direction from the front side (front side) to the back side (rear side) of the paper passing through the cores 28a and 28b of the electromagnets 27a and 27b on both sides, the wire U phase 2u, and the wire The direction of the external magnetic field from the top to the bottom generated by the W phase 2w is perpendicular. That is, in the direction of the external magnetic field from the upper side to the lower side generated by the electric wire U phase 2u and the electric wire W phase 2w, from the front side (front side) of the paper passing through the cores 28a, 28b of the electromagnets 27a, 27b on both sides, There is no component of the magnetic field direction in the direction (rear side). As a result, the magnetic rotating elements 26a and 26b are not affected by the external magnetic field generated by the electric wire U phase 2u and the electric wire W phase 2w, so that the display body 25 does not rotate and is stabilized.

As described above, according to the embodiment described above, the following effects can be obtained.
(1) A magnetic rotating element fixed on both sides of the rotating shafts 24 a and 24 b provided on the display body 25, and the magnetic rotating elements 26 a and 26 b are opposed to each other and parallel to the axial direction of the electric wire 2. Electromagnets 27a and 27b. Therefore, even if a magnetic field is generated by the wire U phase 2u and the wire W phase 2w when an overcurrent flows through the wire U phase 2u and the wire W phase 2w different from the attached wire V phase 2v, the overcurrent The direction of the same magnetic field passing through the passage indicator 1 and the direction of the magnetic field passing through the cores 28a, 28b of the electromagnets 27a, 27b are substantially perpendicular and are not affected. As a result, it is possible to prevent the influence of the magnetic field due to the wires of the other phase.

Moreover, since it comprised in this way, it is not influenced by an external magnetic field and it is not necessary to attach a magnetic field shielding board. Therefore, there is no increase in the number of parts and work man-hours due to the attachment of the magnetic shielding plate.
(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to FIG. The overcurrent passage indicator 1 of this embodiment is different from the first embodiment in that the right electromagnet 27a is located in front of the magnetic rotating element 26a. Hereinafter, a description will be given focusing on differences from the first embodiment.

  As shown in FIG. 7, the right electromagnet 27 a and the left electromagnet 27 b are parallel to the axial direction of the electric wire 2 and both are in opposite directions, that is, front and rear. It arrange | positions so that it may face in each direction. Specifically, the right electromagnet 27a is disposed on the front side of the right magnetic rotating element 26a, and the left electromagnet 27b is disposed on the rear side of the left magnetic rotating element 26b. In the present embodiment, during normal power transmission, the front side of the right core 28a is set to the S pole and the rear side is set to the N pole, and the front side of the left core 28b is set to the S pole and the rear side is set to N. It is set to be the magnetic pole of the pole. In addition, when the passage of overcurrent is detected, the right coil 29a is excited, the front side of the right core 28a is converted to the N pole, and the rear side is changed to the S pole, and the left coil 29b is excited and the left core 28b is excited. The front side is converted to a magnetic pole of N pole and the rear side is changed to S pole. That is, the electromagnets 27a and 27b are set so that the magnetic poles are the same on the left and right sides.

  Thus, by arranging the electromagnets 27a and 27b one by one in the front-rear direction and one by one in the left-right direction, the weight balance can be improved in the front-rear direction and the left-right direction.

  During normal power transmission, the right magnetic rotating element 26a attracted to the rear north pole of the right core 28a of the right electromagnet 27a is set to a position where the south pole magnet layer is the front side, and the left side of the left electromagnet 27b. The left magnetic rotating element 26b attracted to the front S pole of the core 28b is set at a position where the N pole magnet layer is the rear side. Thereby, the white normal display part 25a on the display body 25 is arrange | positioned in the lower position exposed to the transparent cover 30 side.

  On the other hand, when an overcurrent exceeding a predetermined value is detected due to a short circuit or the like, the right coil 29a of the right electromagnet 27a is excited and the front side of the right core 28a is changed to the N pole and the rear side is changed to the S pole. The S pole magnet layer of the element 26a repels the rear magnetic pole of the right core 28a, and a rotational force is induced in the right magnetic rotating element 26a. Also, the left coil 29b of the left electromagnet 27b is excited, the front side of the left core 28b is converted to the N pole and the rear side is changed to the S pole, and the N pole magnet layer of the left magnetic rotating element 26b is the front side of the left core 28b. A repulsive force is induced in the left magnetic rotating element 26b in a repulsive manner with respect to the magnetic pole. Thereby, the magnetic rotating elements 26a and 26b and the display body 25 are rotated so that the N pole magnet layer of the right magnetic rotating element 26a is arranged on the front side, and the S pole magnet layer of the left magnetic rotating element 26b is moved to the rear side. Placed on the side. That is, the right magnetic rotating element 26a attracted to the rear S pole of the right core 28a of the right electromagnet 27a is held at the position where the N pole magnet layer is the front side, and the left core of the left electromagnet 27b. The left magnetic rotating element 26b attracted to the front N pole 28b is held at a position where the S pole magnet layer is the rear side. Therefore, the red abnormality display part 25b on the display body 25 is arranged in a state exposed to the transparent cover 30 side.

  Even in such a configuration, as in the first embodiment, the magnetic field direction from the front side (front side) of the paper passing through the cores 28a, 28b of the electromagnets 27a, 27b on both sides to the back side (rear side) of the paper surface The direction of the external magnetic field from the upper side to the lower side generated by the electric wire U phase 2u and the electric wire W phase 2w is perpendicular. That is, in the direction of the external magnetic field from the upper side to the lower side generated by the electric wire U phase 2u and the electric wire W phase 2w, from the front side (front side) of the paper passing through the cores 28a, 28b of the electromagnets 27a, 27b on both sides, There is no component of the magnetic field direction in the direction (rear side). As a result, the magnetic rotating elements 26a and 26b are not affected by the external magnetic field generated by the electric wire U phase 2u and the electric wire W phase 2w, so that the display body 25 does not rotate and is stabilized.

As described above, according to the embodiment described above, in addition to the function and effect of (1) of the first embodiment, the following function and effect can be achieved.
(2) Since the electromagnets 27a and 27b are arranged one by one in the front-rear direction and one by one in the left-right direction, the weight balance can be improved in the front-rear direction and the left-right direction.

In addition, the said embodiment can be implemented with the following forms which changed this suitably.
In the first embodiment, the electromagnets 27a and 27b are arranged on the rear side of the central axis of the display body 25, but the electromagnets 27a and 27b are arranged on the front side of the central axis of the display body 25, respectively. You may make it install.

  In the second embodiment, the right electromagnet 27a is disposed on the front side of the right magnetic rotating element 26a, and the left electromagnet 27b is disposed on the rear side of the left magnetic rotating element 26b. 27a may be disposed behind the right magnetic rotating element 26a, and the left electromagnet 27b may be disposed in front of the left magnetic rotating element 26b.

  In the above embodiment, the electromagnets 27a and 27b and the magnetic rotating elements 26a and 26b are provided on both sides of the display body 25. However, the electromagnets 27a and 27b and the magnetic rotating elements 26a and 26b are provided on the left and right sides of the display body 25. It may be provided only on one side. For example, as shown in FIG. 6, the left electromagnet 27b of the first embodiment is not provided.

  In the above embodiment, the magnetic poles of the right electromagnet 27a and the left electromagnet 27b are normally the S pole on the front side and the N pole is the rear side, but the magnetic poles of the right electromagnet 27a and the left electromagnet 27b are normally the N pole on the front side. The rear side may be the S pole.

  In the above embodiment, the magnetic poles of the right electromagnet 27a and the left electromagnet 27b are normally oriented in the same direction with the front side being the S pole and the rear side being the N pole. You may make it become a different direction.

In the above embodiment, one electromagnet and a magnetic rotating element are provided on one side, but a plurality of electromagnets and a plurality of magnetic rotating elements may be provided on one side.
In the above embodiment, the overcurrent passage indicator 1 is attached to all the three-phase electric wires, but it can be attached to any two phases of the three phases. Even in this way, the same effect can be obtained.

The partially broken front view of an overcurrent passage indicator. The A arrow directional view of the display part of an overcurrent passage indicator. The perspective view of a magnetic rotating element. The perspective view which shows the magnetic field at the time of the attachment to the distribution line of an overcurrent passage indicator. The side view which shows the magnetic field at the time of the attachment to the distribution line of an overcurrent passage indicator. The figure which shows the display part of an overcurrent passage indicator. The figure which shows the display part of an overcurrent passage indicator. The perspective view which shows the attachment to the distribution line of an overcurrent passage indicator. The figure which shows the magnetic field at the time of the attachment to the distribution line of an overcurrent passage indicator.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,101 ... Overcurrent passage indicator, 2, 2u, 2v, 2w, 102u, 102v, 102w ... Electric wire, 10 ... Detection part, 20 ... Display part, 21 ... Case, 22 ... Mounting plate, 23a, 23b, 123 ... support member, 24a, 24b, 124 ... rotating shaft, 25, 125 ... display, 26a, 26b, 126 ... magnetic rotating element, 27a, 27b, 127 ... electromagnet, 28a, 28b, 128 ... core, 29a, 29b, 129 ... Coil, 30 ... Transparent cover.

Claims (3)

It is mounted in a suspended state with the distribution line clamped, and the current flowing through the distribution line is detected, and when an overcurrent occurs, the display body is reversed from the normal display state to the abnormal display state with the rotation axis as the center. In the overcurrent passage indicator,
The driving means includes a magnetic rotating element fixed to at least one of both sides of the rotating shaft of the display body, and faces the magnetic rotating element and has a central axis parallel to the axial direction of the distribution line. An overcurrent passage indicator, comprising: an electromagnet provided to be. The overcurrent passage indicator according to claim 1,
The magnetic rotating element is provided on both sides of the rotating shaft of the display body,
Each of the electromagnets arranged to face the magnetic rotating element faces the same direction and is arranged in parallel. The overcurrent passage indicator according to claim 1 or 2,
The magnetic rotating element is provided on both sides of the rotating shaft of the display body,
Each of the electromagnets arranged to face the magnetic rotating element faces in the opposite direction and is arranged in parallel.

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