JP2955104B2 - Cable head for device connection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable head for connecting equipment between a cable line and equipment.

[0002]

2. Description of the Related Art When high-voltage devices such as GIS (gas-insulated circuit breakers) are connected to each other by cable lines, the following configuration is generally employed. FIG. 2 shows a side view of a conventional device and a cable head for device connection. In the figure, a device 1 is, for example, a high-voltage device such as the GIS described above, and a cable line 4 is connected to a wall surface 2 of the device 1 via a bushing 3. An internal device 5 of the device 1 is electrically connected to the bushing 3 via a bus 6. Also, device 1
Is insulated by an insulating gas 7 such as sulfur hexafluoride. When installing such equipment, it is necessary to conduct an electrical test of the entire apparatus after completing the installation of the bushing 3 and the like, in addition to individually performing an electrical test on the device 1 and the cable line 4 in advance. In this case, an AC voltage for testing is applied through the cable line 4, so-called A
A C pressure resistance test and the like are performed.

[0003]

Generally, the cable line 4 has an extremely large capacitance as compared with the equipment 1 or the like. Accordingly, when a so-called DC withstand voltage test in which a high DC voltage is applied is performed, the electrical characteristics of the cable line 4 can be accurately grasped. However, when the DC withstand voltage test is performed after the cable line 4 is connected to the device 1, the following problem occurs. That is, the inside of the device 1 is filled with the insulating gas 7, and a considerable amount of dust is floating in the insulating gas 7. Therefore, when a high DC voltage is applied to the bus 6 or the like through the cable line 4, dust is intensively adhered to the inside of the device by the so-called electric precipitator principle. For this reason, there is a possibility that the insulation performance in the device 1 may be reduced. As described above, conventionally, there is a problem that it is difficult to perform the DC withstand voltage test on the cable line 4 after the cable line 4 is attached to the device 1. The present invention has been made in view of the above points, and can perform a DC withstand voltage test of a cable line connected to a device with good workability while preventing a DC voltage from being applied to the inside of the device. It is an object of the present invention to provide a device connection cable head.

[0004]

A cable head for connecting a device according to the present invention is electrically connected to an internal circuit of the device and is connected to the device.
A device side terminal disposed in the device, protrudingly provided in the device,
The cable line for energizing the internal circuit is electrically connected
A cable bushing having a conductor withdrawal rod
One end is swingably attached to the conductor drawing rod, and the other end is
Is electrically conductive and detachably connected to the device side terminal.
To the cable line
The power application cable for applying the test voltage is electrically connected.
A test bushing having internal electrodes
Electrical connection to the poles and from the test bushing to the
It protrudes into the device and is connected to the movable piece.
To separate the other end of the movable piece from the device-side terminal.
And a stick.

[0005]

[Function] This cable head has an electric cable
A cable bushing having a conductor withdrawal rod connected thereto;
Test with internal electrodes electrically connected to the power application cable
A bushing is provided. Pull out conductor of cable bushing
A movable piece is attached to the rod, and this movable piece
Electrically connected to the device side terminal connected to the
It is. The operation provided on the test bushing so that it can be advanced
The rod is connected to the movable piece, and the movable piece is
Disconnect from side terminal. As a result, from the voltage application for cable
When applying high DC voltage to the cable line,
Disconnect from the device side terminal and apply DC high voltage to the internal circuit of the device.
Block application. Also, during normal use, move the movable piece
To the cable terminals and the internal circuit of the equipment.
Make an electrical connection.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. FIG. 1 is a longitudinal sectional view showing an embodiment of a cable head for device connection according to the present invention. FIG. 1 (a) is a longitudinal sectional view of the cable head, and FIG. FIG. 1C is a perspective view of a main part of the switch. In FIG. 1A, a cable bushing 21 for accommodating the end of a cable line 20 is attached to the inside of the wall surface 2 of the device . On the other hand, cable line 2
0 is fixed to the outside of the wall surface 2 of the device using the protective case 22. A conductor lead bar 23 electrically connected to the conductor of the cable line 20 is drawn from the tip of the cable bushing 21.

[0007] In addition, a test bushing 31 for accommodating the end of the power application cable 30 is attached to the wall surface 2 of the device. The test bushing 31 is attached to and detached from the cable line 20 only at the end of a DC withstand voltage test for applying a high DC voltage to the cable line 20 and the wall surface 2 of the device.
And a fixing portion 31B which is fixed to the fixing portion 31B. The conductor sleeve 32 is provided on the right end face of the fixing portion 31B in the drawing.
Is provided. The internal electrode 33 is arranged so as to surround the conductor sleeve 32. The terminal of the power application cable 30 is surrounded by a spacer 34, and a terminal 36 is compression-connected to the exposed conductor 35. FIG.
As shown in (b), the terminal 36 includes a compression section 36A and a terminal section 36B. The terminal portion 36B is provided with a through hole 36C, and the conductor sleeve 32 is inserted into the through hole 36C.

Further, through holes are provided at the center of the fixing portion 31B and the center of the conductor sleeve 32, and the operating rod 37 is slidably inserted into these through holes. This operation
The working rod 37 is a through hole of the conductor sleeve 32 and is slidably attached in the axial direction. On the other hand, inside the device, a knife-shaped movable piece 10 that swings in the direction of arrow 11 is pivotally supported by the conductor extraction rod 23 of the cable bushing 21. The central portion of the knife-shaped movable piece 10 is pivotally supported via a shaft 37A to the tip of an operation rod 37 projecting from a fixed portion 31B of the test bushing 31 and is thereby connected to each other. In addition, the movable piece 1
A contact 12 for reducing the contact resistance at the time of electrical connection is attached to the tip of 0.

On the other hand, a device-side terminal 13 is fixed via an insulator 14 to the inside of the wall surface 2 of the device. FIG. 1 (c)
As shown in FIG. 2, the device-side terminal 13 is provided with a groove 13A, and the distal end of the movable piece 10 is fitted into the groove 13A to establish electrical connection with the device-side terminal 13 by the contact 12. It is configured to be turned on and off via a switch. A push fitting 41 that is screwed into a thread groove 32A formed on the outer periphery of the conductor sleeve 32 is provided on the attaching / detaching portion 31A of the test bushing 31. While rotating the press fitting 41, when screwed into the conductor sleeve 32, projections 41A provided at the center to press the end surface of the operating rod 37, fixed to push toward the operating rod 37 inside the equipment It slides with respect to the part 31B. Therefore, when the push fitting 41 is screwed into the state as shown in FIG. 1A, the operating rod 37 rotates the movable piece 10 to rotate the device-side terminal 1.
Turn off between 3. Further, the press fitting 41 is integrated with a tapered insulating portion 42 made of EP rubber or the like. A buried nut 43 is buried and fixed on the enlarged diameter side of the insulating portion 42. The push fitting 41 forms an off-operation blind plug 40 together with the insulating portion 42 and the embedded nut 43. That is, by rotating the embedded nut 43, the push fitting 41 is rotated, and the operation rod 37 is protruded to the inside of the device as described above.
Then, when the pressing fitting 41 is sufficiently fastened to the conductor sleeve 32, the insulating portion 42 is pressed against the tapered inner wall surface of the attaching / detaching portion 31A with a constant pressure, thereby securing electrical insulation from the outside.

The above-described device connecting cable head is connected to a cable line 20 as shown in FIG.
When performing the pressure resistance test, the attaching / detaching portion 31A to which the power application cable 30 is attached is attached to the fixing portion 31B, and the turning-off blind plug 40 is attached while rotating as described above. As a result, the operation rod 37 rotates and pushes up the movable piece 10 , and cuts off the electrical connection between the conductor extraction rod 23 of the cable line 20 and the device-side terminal 13. on the other hand,
The conductor 35 of the power application cable 30 is electrically connected to the operation rod 37 via the conductor sleeve 32 and the like. Therefore, the power supply cable 30 is electrically connected to the cable line 20 through the operation rod 37, the movable piece 10, and the conductor extraction rod 23 of the cable line 20, so that a high DC voltage can be applied to the cable line 20. it can. After the above-described DC withstand voltage test is completed, first, the blind plug for off operation 40 is rotated in a direction opposite to the direction in which the blind plug 40 is mounted, so that the conductor sleeve 32 and the press fitting 41 are separated. After that, the detachable portion 31A is
When the terminal 36 is moved rightward in FIG. 1A, the terminal 36 shown in FIG. 1B is detached from the conductor sleeve 32, and the attaching / detaching portion 31A and the power application cable 30 are detached from the fixing portion 31B.
Thereafter, electrical protection is performed by attaching the following members to this portion.

FIG. 3A is a longitudinal sectional view of the cable head of the present invention in a normal use. In the drawing, the blind lid 50 is attached to the fixing portion 31B during normal use. The blind lid 50 includes an internal electrode 51 surrounding the conductor sleeve 32, an insulator 52 insulating the outer periphery thereof, and a protective coating 53. In addition, the attachment / detachment portion 31A and the blind cover 50 shown in FIG. 1 have portions surrounding the internal electrodes made of insulating EP rubber or the like. At the right end of the blind lid 50, an on-operation blind plug 60 is attached. An operation section 61 is embedded in the inner end face of the ON operation blind plug 60. A buried nut 63 is provided on the outer end face, and the remaining part is integrally molded by the insulating part 62. FIG. 3B shows the end surface of the operation rod 37.
FIG. 3 shows an enlarged cross-sectional view of the operation unit 61. As shown in the figure, a spring-like contact 37B is attached to the end of the operating rod 37 in order to reduce the contact resistance at the time of electrical connection between the outer peripheral surface and the conductor sleeve 32. . The spring-like contact 37B ensures the electrical connection between the conductor 35 of the power application cable 30 and the operating rod 37 during the DC withstand voltage test shown in FIG.

On the other hand, a screw hole 37C is provided at the end of the operation rod in the axial direction. And this screw hole 37C
, One end of the operation unit 61 is screwed. That is, when the embedded nut 63 shown in FIG. 3A is rotated, the insulating part 62 and the operating part 61 integrated therewith rotate. As a result, the tip of the operation unit 61 is operated.
The rod 37 is screwed into the screw hole 37C. The on-operation blind plug 60, which is prevented the movement by blind lid 50, operating rod 37 by the rotation of the operation unit 61 is gradually attracted to the right in FIG. 3 (a). Therefore, the movable piece 1
0 is the device-side terminal 13 as shown in FIG.
In the groove 13A described with reference to FIG. Therefore, the cable line 20 is electrically connected to the device-side terminal 13 via the conductor pullout bar 23 of the cable bushing 21 that receives the end of the cable line 20 and the movable piece 10. The present invention is not limited to the above embodiments. Above movable
The mechanism for operating the piece 10, the connection mechanism for the power application cable, the removal mechanism, and the like are not limited to the above-described embodiment, and may be variously modified. Also, the direction of relative movement of the operating rod 37 to the device wall surface 2 is not necessarily perpendicular to the device wall surface 2,
For example, rotation or other movement may be used.

[0013]

According to the cable head for device connection of the present invention described above, the movable piece is operated by the operating rod,
Switch between the power supply cable and the internal circuit of the equipment on the track
As a result, a high DC voltage applied to the cable line is not applied to the inside of the device during the DC withstand voltage test. The on the movable piece, off operation may be on can be performed safely from the outside, as also high electrical reliability from the movable piece itself is provided inside the device. Thereby, at the time of the DC withstand voltage test of the cable line, it is possible to prevent a high DC voltage from being applied inside the device and to prevent dust from adhering to the inner wall or the like of the device. In addition, the use of an insulating plug instead of a simple insulating gas eliminates the need for degassing or other processing inside the bushing.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a cable head for device connection of the present invention.

FIG. 2 is a longitudinal sectional view of a conventional general device and a cable head.

FIG. 3 is a longitudinal sectional view of the cable head for device connection of the present invention at the time of normal use.

[Explanation of symbols]

2 Wall surface of equipment 10 Knife-shaped movable piece 20 Cable line 21 Cable bushing 23 Conductor lead-out rod 30 Cable for power application 31 Test bushing 32 Conductor sleeve 36 Terminal 40 Off-operation blind plug 41 Push fitting 50 Blind lid 60 On-operation blind plug

──────────────────────────────────────────────────続 き Continuation of the front page (72) Tadashi Kase 2-1, 1-1 Sakae Oda, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside Showa Electric Cable Co., Ltd. (56) References JP-A-4-265617 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) H02G 15/00-15/196

Claims (1)

(57) [Claims] An electronic circuit connected to an internal circuit of the device;
Device side terminals arranged in the device, and protrudingly provided in the device to supply current to the internal circuit.
Cable conductors have conductor draw-out rods that are electrically connected
A cable bushing, one end of which is swingably attached to the conductor drawing rod, and
A conductive terminal whose end is detachably connected to the device side terminal.
A test piece attached to the moving piece and the equipment and connected to the cable line.
Inside the power supply cable for applying voltage
A test bushing having an internal electrode; and the test bushing electrically connected to the internal electrode.
Projecting into the device from the
Moving the other end of the movable piece from the device side terminal
And an operating rod for disconnecting.
Table head.