JPH0220741Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an auxiliary contact for a disconnector that can open and close a relatively large loop current many times, such as in a substation busbar circuit.

PRIOR ART When the bus configuration of a substation in which a disconnector is used is a double main bus system, the disconnector may open and close a loop current. The magnitude of this loop current that is opened and closed may be as large as the positive current value of a disconnector, and the recovery voltage increases as the system voltage of the substation increases or as the bus bar length increases.
If such a loop circuit is opened and closed using a normal disconnector, the main contact will be burnt out due to arcing, resulting in poor contact of the main contact and, ultimately, an overheating accident of the main contact when energized. Therefore, the disconnector for opening and closing the loop circuit is provided with an auxiliary contact near the main contact. In particular, auxiliary contacts made of arc-resistant metal are used for switching in high-voltage and large-current systems, but they still burn out considerably and affect the opening/closing operation of the disconnect switch, so in general, a butt contact is used instead of a sliding contact. A contact type auxiliary contact is installed.

As a disconnector equipped with the above-mentioned butt contact type auxiliary contactor, one shown in FIG. 3a has conventionally been used. To explain this, finger-shaped and block-shaped main contacts 22 and 23 are fixed to the tips of the disconnector blades 20 and 21, and similarly, the blades 20 and 21 are opposite to the opening direction of the blades 20 and 21. Brackets 24 are supported in a cantilevered manner in the direction, and arc-shaped auxiliary contacts 26 are rotatable at the tips of these brackets 24 via pins 25, and their convex surfaces are connected to the main contacts 22, 23. They are supported so as to be in contact with each other in the vicinity. Incidentally, a torsion spring (not shown) is provided between the bracket 24 and the auxiliary contact 26 so that both the auxiliary contacts 26 are pressed against each other. In such a conventional disconnector, the auxiliary contact 26 is attached in the vicinity of the main contacts 22 and 23 in a substantially human shape, and after the main contacts 22 and 23 are separated, the auxiliary contact 26
The structure is such that an arc is generated when the auxiliary contact 2 opens as shown in Figure 3b.
6 to locally form an annular path, and the area of the annular path is further expanded by electromagnetic force, thereby interrupting the above-mentioned loop current. However, the recovery voltage of the ring path is about 300V, the length of the arc is short, and the size of the arc is determined by the size of the loop current, so the main contacts 22 and 23 open and the current transfers to the auxiliary contact 26. Until the auxiliary contact 26 opens and an arc occurs, the current flowing through the auxiliary contact 26 becomes a reciprocating circuit as shown by the arrow i in FIG. The auxiliary contactor 26 is about to be opened by the electromagnetic force shown. In particular, when the current becomes large (5000A or more), the effect is large and the auxiliary contact repeatedly separates until it opens, and each time an arc is generated to interrupt the current and the auxiliary contact 2
6 is severely damaged and its lifespan is extremely shortened, and in some cases it is defective in that it becomes unusable after being shut off several times.

Purpose of the invention The present invention was made in order to eliminate the above-mentioned defects, and its purpose is to control the contact/disconnection operation before the auxiliary contact opens/disconnects due to the electromagnetic force based on the reciprocating current when the loop circuit is opened/closed. An object of the present invention is to provide an auxiliary contact for a disconnector that can improve durability by preventing repetition.

Structure of the invention In order to achieve the above object, the invention is structured so that a pair of blades supported by a support insulator are opened and closed in a double-door style, and an electric circuit is opened and closed between a pair of main contacts attached to the tips of the blades. In the disconnector, a first support member is attached to one of the blades in a circuit-opening direction substantially perpendicular to the blade, and a second support member is attached to the other blade in a circuit-closing direction substantially perpendicular to the blade. Attachment, first and second auxiliary contacts each having a substantially arc shape that are in contact with each other with their convex surfaces in a closed circuit state are cantilever-supported at the distal ends of both of the support members, and further, one of the two auxiliary contacts is At least one of them is rotatable and biased to rotate so as to come into pressure contact with the other auxiliary contact.

Embodiment Hereinafter, an embodiment embodying the present invention will be explained with reference to FIGS. 1 and 2. In the drawings, 1 indicates a frame;
2 is a base of a disconnector mounted on a frame; 3 is a lever rotatably supported on the left end of the base 2 via a bearing (not shown); 4 is also a base 2
A lever 5 is rotatably supported on the right end of the lever via a bearing (not shown); 5 is an interlocking link connected to the levers 3 and 4 by pins 6 and 7;
9 is a support insulator fixed on the levers 3 and 4, and a cap-shaped electrode portion 1 is provided on the top of the insulator.
0 is inserted.

11 and 12 are blades fixed to the electrode section 10, 13 is a finger-shaped main contact attached to the tip of one blade 11, and 14 is a block-shaped main contact attached to the tip of the other blade 12. It is a contact and is inserted into the main contact 13 and brought into contact therewith. Reference numeral 15 denotes an L-shaped first support member that is cantilevered perpendicularly to the blade 11 in the opening direction thereof.
b is provided. 16 is the bracket 15
The auxiliary contact is an arc-shaped first auxiliary contact rotatably supported by a pin 17 on the supporting pieces 15a, 15b, and a second auxiliary contact is supported by a torsion spring (not shown) wound around the pin 17. In figure a, it is biased counterclockwise. Reference numeral 18 denotes a bracket serving as a second support member in an L-shape, which is supported in a cantilever direction perpendicularly to the blade 12 in the direction of closing the blade, and reference numeral 19 is a circle supported in a cantilever manner to the upper end of the bracket 18. An auxiliary contact as a second auxiliary contact having an arc shape, FIG.
The auxiliary contact 16 is contacted in the closed state of the disconnector shown in FIG. I try to do that. Furthermore, in this closed state, the auxiliary contact 16 is pressed against the auxiliary contact 19 by a torsion spring (not shown), and when both the auxiliary contacts 16 and 19 are separated from each other in the open state of the disconnector, one of the auxiliary contacts The contactor 16 is rotated by a fixed angle around a pin 17 by a torsion spring, and then stopped at a predetermined position using a part of the bracket 15.

Next, the operation of the disconnector configured as described above will be explained.

In FIG. 1, when the lever 3 is rotated counterclockwise by the operating device, the lever 4 is rotated clockwise via the pin 6, the interlocking link 5, and the pin 7, so that the support insulator 8 and blade 11
is rotated counterclockwise, and the support insulator 9 and blade 12 are rotated clockwise, respectively, so that both blades 11 and 12 are opened double. both blades 1
By rotating the main contacts 1 and 12, the main contacts 13 and 14 provided at their tips are released from contact, and the electrical circuits of the main contacts 13 and 14 are opened. In this state, the current flows along the path of blade 11 → bracket 15 → pin 17 → auxiliary contact 16 → auxiliary contact 19 → bracket 18 → blade 12.

The auxiliary contact 16 is pressed against the auxiliary contact 19 by a torsion spring (not shown) provided at the pin 17 position while the main contacts 13 and 14 are moved to a predetermined separation position. When contacts 11 and 12 are opened, the auxiliary contact 16 engages a stopper (bracket 1) that prevents its rotation in the counterclockwise direction.
5), it will no longer rotate around the pin 17 and will be separated from the auxiliary contact 19.
And when both auxiliary contacts 16 and 19 are separated,
The current is cut off and the opening operation ends.

Note that the circuit-closing operation is the opposite of the aforementioned circuit-opening operation, and the auxiliary contacts 16 and 19 first come into contact with each other, and then the main contacts 13 and 14 come into contact, resulting in a closed circuit state.

Now, in the embodiment of the present invention, a bracket 15 is attached to one blade 11 in a direction perpendicular to the blade 11 to open the circuit, and a bracket 18 is attached to the other blade 12 in a direction perpendicular to the blade 12 to close the circuit. Furthermore, both brackets 1
At the tips of 5 and 18, there is an auxiliary contact 1 having a substantially arc shape whose convex surfaces are in contact with each other in a closed circuit state.
6 and 19 are each supported in a cantilever manner, and furthermore, the auxiliary contact 16 is rotatable and biased to rotate so as to come into pressure contact with the auxiliary contact 19 by a torsion spring provided at the position of the pin 17. Therefore, main contact 1
It is possible to eliminate the generation of electromagnetic force due to the reciprocating current while the auxiliary contacts 16 and 19 are opened after the auxiliary contacts 3 and 14 are opened, and therefore, the repeated contact and separation of both the auxiliary contacts 16 and 19 can be eliminated and damage to them can be avoided. This can be significantly reduced.

In addition, in the embodiment of the present invention, the brackets 15, 18 and the auxiliary contacts 16,
19 through a substantially S-shaped path, repulsive electromagnetic force q acts between the bracket 15 and the auxiliary contact 16 and between the bracket 18 and the auxiliary contact 19, as shown by the arrows in the figure. As a result, a force pressing against each other acts between the auxiliary contacts 16 and 19, and there is an advantage that poor contact between the auxiliary contacts during the circuit opening or closing operation can be eliminated.

Note that the present invention can also be embodied in the following embodiments.

Either the auxiliary contact 16 is cantilevered and fixed to the bracket 15 mounted in the opening direction, and the auxiliary contact 19 is rotatably supported on the bracket 18 mounted in the closing direction, or furthermore, the auxiliary contact 16 is ，
19 shall be rotatably supported.

Effects of the Invention As detailed above, the present invention eliminates the electromagnetic force acting on the auxiliary contact that tends to separate the contact during the opening/closing operation of the electric circuit, and repeatedly connects and disconnects the auxiliary contact. This invention is excellent as an auxiliary contact for a disconnector because it can prevent this, improve the durability of the auxiliary contact, and enable smooth circuit operation.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment embodying the present invention, FIG. 2a is a plan view of the main part showing a closed circuit state,
Fig. 2b is a plan view of the main part showing the main contact in the open state and the auxiliary contact in the closed state, Fig. 2c is a plan view showing the state of action of electromagnetic force during the opening operation, and Figs. 3a to 3 c is a partial plan view for explaining the circuit-opening operation of the auxiliary contact of the conventional disconnector. 11, 12...blade, 13, 14...main contactor, 15...bracket as first support member, 16...first auxiliary contactor, 18...bracket as second support member, 19...Second auxiliary contact.

Claims (1)

[Claims for Utility Model Registration] A pair of blades 1 supported by support insulators 8 and 9
1 and 12 are opened and closed in a double-door style to open and close an electric circuit between a pair of main contacts 13 and 14 attached to their tips, one of the blades 11 has its blade 11
The first support member 15 is installed in the opening direction substantially orthogonal to the other blade 12, and
A second support member 18 is attached in the closing direction substantially orthogonal to
First and second auxiliary contacts 16, 19 having substantially arc shapes whose convex surfaces are in contact with each other in a closed circuit state.
are each supported in a cantilever manner, and furthermore, at least one of the auxiliary contacts 16 and 19 is rotatably biased so as to be in pressure contact with the other auxiliary contact 19. Auxiliary contact for disconnector.