JP7172267B2 - Disconnector - Google Patents

Description

The present invention relates to disconnectors.

A fuse is inserted in the electrical path between the primary side of the transformer and the power supply to protect the transformer in the event of a transformer accident. For example, as a means to protect the fuse from the inrush current that occurs when the power is turned on, an inrush current suppression resistor is connected to the primary side of the transformer, and the inrush current is suppressed by the inrush current suppression resistor when the power is turned on. 2. Description of the Related Art There is known a technique of short-circuiting an inrush current suppression resistor in order to operate a transformer normally when a load starts operating (see, for example, Patent Document 1).

JP-A-58-179128

However, in the case of Patent Document 1, there was a problem that a relay circuit for short-circuiting the inrush current suppression resistor and a relay control circuit for controlling the relay circuit had to be mounted.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a disconnector having a simple mechanical structure for protecting a fuse from a rush current generated when power is turned on.

The main invention that solves the above-mentioned problems is a disconnector that opens and closes an electric circuit between a first conductor connected to the primary side of a transformer and a second conductor provided on the upstream side of the first conductor. a third conductor rotatably supported with respect to the first conductor for opening and closing an electric path between the first conductor and the second conductor; and When connecting the fuse, the resistor, and the third conductor interposed in the electric circuit to the second conductor, the resistor is connected to the fuse by contacting the second conductor before the third conductor. a fourth conductor connected in series and then short-circuiting the resistor by contacting the third conductor with the second conductor , the third conductor being closer to the first conductor than the fuse; and a sixth conductor closer to the second conductor than the fuse, one end of the fourth conductor is rotatably supported with respect to the sixth conductor, and the fourth conductor The other end of the conductor is slidably inserted into a hole formed in the sixth conductor toward the second conductor while being insulated from the sixth conductor. It is interposed in the electric path of the fourth conductor .

Other features of the present invention will become apparent from the accompanying drawings and the description herein.

According to the present invention, it is possible to protect the fuse from the inrush current generated when the power is turned on with a simple mechanical structure.

It is a block diagram which shows the example of installation of the disconnecting switch which concerns on this embodiment. It is a side view which shows the state which interrupted the electric circuit by the disconnecting switch which concerns on this embodiment. It is a side view which shows the state which connected the electric circuit by the disconnecting switch which concerns on this embodiment. It is a side view which shows the other state which connected the electric circuit by the disconnecting switch which concerns on this embodiment.

At least the following matters will become apparent from the description of the present specification and the accompanying drawings.

===Installation example of disconnecting switch===
FIG. 1 is a block diagram showing an installation example of a disconnecting switch according to this embodiment. In FIG. 1, only the transformer 1, the rectifier circuit 2, the smoothing capacitor 3, the load 4, and the disconnecting switch 5 are taken up in order to simplify the explanation.

The transformer 1 has a primary winding 1A and a secondary winding 1B. According to the turns ratio of the primary winding 1A and the secondary winding 1B, the power is supplied from the upstream transmission/distribution line to the primary winding 1A. It is a voltage conversion device that steps down the supplied AC voltage and outputs the stepped-down AC voltage from the secondary winding 1B.

The rectifier circuit 2 is a circuit that, for example, full-wave rectifies the AC voltage output from the secondary winding 1B of the transformer 1 .

The smoothing capacitor 3 is an element that smoothes the full-wave rectified voltage output from the rectifier circuit 2 so that the load 4 in the subsequent stage operates.

The disconnecting switch 5 is a device that disconnects an electric circuit between the transformer 1 and a transmission/distribution line on the upstream side of the transformer 1 . Therefore, the disconnector 5 is inserted in the electric path between the first conductor 6 connected to the primary winding 1A and the second conductor 7 provided upstream of the first conductor 6. . The disconnecting switch 5 includes a fuse for protecting the transformer 1, but there is a risk that the fuse will blow due to the inrush current generated when the electric circuit between the first conductor 6 and the second conductor 7 is closed. . Therefore, in order to solve this problem, the disconnector 5 connects the resistor in series with the fuse when the electric path between the first conductor 6 and the second conductor 7 is closed, and then short-circuits the resistor. It has a mechanical structure that realizes Details of the disconnector 5 will be described later.

=== Configuration of Disconnecting Switch ===
FIG. 2 is a side view showing a state in which an electric circuit is cut off by the disconnecting switch according to this embodiment. FIG. 3 is a side view showing one state in which the electric circuit is connected by the disconnecting switch according to the present embodiment. FIG. 4 is a side view showing another state in which the electric circuit is connected by the disconnecting switch according to this embodiment.

The disconnector 5 includes a third conductor 51 , a fuse 52 , a resistor 53 , a fourth conductor 54 and a spring body 55 .

The third conductor 51 is a conductor that is rotatably supported with respect to the first conductor 6 in order to connect or disconnect the electric path between the first conductor 6 and the second conductor 7 . For example, when the third conductor 51 rotates clockwise around the support shaft S1, the disconnector 5 cuts off the electric circuit between the first conductor 6 and the second conductor 7, while the third conductor 51 is supported. When rotated counterclockwise about the axis S1, the disconnector 5 connects the electrical path between the first conductor 6 and the second conductor 7 . The third conductor 51 is composed of a fifth conductor 51A and a sixth conductor 51B, and the fifth conductor 51A and the sixth conductor 51B are connected via a fuse 52. The fifth conductor 51A is closer to the first conductor 6 than the fuse 52 and is connected to the first conductor 6 via the support shaft S1. The sixth conductor 51B is closer to the second conductor 7 than the fuse 52, and connects or disconnects the electric path with the second conductor 7 as the fifth conductor 51A rotates. For example, the tip of each of the sixth conductor 51B and the second conductor 7 presents a shape of the knife switch insertion side and the insertion side, and when the sixth conductor 51B is inserted into the second conductor 7, the sixth conductor 51B 2 maintains a state of being connected to the conductor 7. For example, by operating an insulating lever (not shown) coupled to the fifth conductor 51A or the sixth conductor 51B, the fifth conductor 51A is rotated and the sixth conductor 51B is connected to the second conductor 7. connect or disconnect

Resistor 53 is an element that is connected in series with fuse 52 or short-circuited depending on the operation of third conductor 51 and fourth conductor 54 .

The fourth conductor 54 connects the resistor 53 in series with the fuse 52 by contacting the second conductor 7 before the third conductor 51 when connecting the third conductor 51 to the second conductor 7, After that, the third conductor 51 is a conductor that short-circuits the resistor 53 by contacting the second conductor 7 . The fourth conductor 54 consists of a seventh conductor 54A and an eighth conductor 54B. The seventh conductor 54A is connected to the sixth conductor 51B via a support shaft S2 and is rotatably supported with respect to the sixth conductor 51B. The seventh conductor 54A rotates around the spindle S2 on the opposite side of the sixth conductor 51B to the second conductor 7 . The eighth conductor 54B consists of a ninth conductor 54C and a tenth conductor 54D. The ninth conductor 54C is a conductor closer to the seventh conductor 54A than the resistor 53, is connected to the seventh conductor 54A via a support shaft S3, and is rotatable with respect to the seventh conductor 54A. supported. The tenth conductor 54D is a conductor closer to the second conductor 7 than the resistor 53, and protrudes toward the second conductor 7 with respect to the hole 51C formed in the sixth conductor 51B. It is slidably inserted. The outer peripheral surface of the tenth conductor 54D is insulated from the inner peripheral surface of the hole 51C. For example, a member made of an insulating material may be attached to the outer peripheral surface of the tenth conductor 54D or the inner peripheral surface of the hole 51C. Note that the resistor 53 is provided on the opposite side of the sixth conductor 51B to the side where the tenth conductor 54D protrudes.

The spring body 55 is arranged such that when the sixth conductor 51B is not in contact with the second conductor 7, the tenth conductor 54D protrudes from the hole 51C in the direction of the second conductor 7. It is a coil spring that elastically urges between the conductor 54A.

=== Connection operation of the disconnecting switch ===
First, in order to connect the electric circuit between the first conductor 6 and the second conductor 7 , the operator operates the insulation lever in a direction approaching the second conductor 7 .

As the insulation lever is operated, the fifth conductor 51A rotates counterclockwise around the support shaft S1, and the sixth conductor 51B approaches the second conductor .

The tenth conductor 54</b>D protrudes from the hole 51</b>C of the sixth conductor 51</b>B by the elastic force of the spring body 55 . Therefore, when the sixth conductor 51B approaches the second conductor 7 , the tenth conductor 54D contacts the second conductor 7 before the sixth conductor 51B contacts the second conductor 7 . This contact connects the resistor 53 in series with the fuse 52 in the electrical path between the first conductor 6 and the second conductor 7 . Therefore, it is possible to protect the fuse 52 from the rush current. After that, the sixth conductor 51B contacts the second conductor 7 against the elastic force of the spring body 53 . This contact short-circuits the resistor 53 in the electrical path between the first conductor 6 and the second conductor 7 . Therefore, since current flows only through the fuse 52, the transformer 1 can operate normally. The second conductor 7 and the sixth conductor 51B maintain a connected state by fitting the shape of the inserting side of the knife switch to the inserting side.

=== Breaking operation of disconnecting switch ===
First, in order to cut off the electric circuit between the first conductor 6 and the second conductor 7 , the operator operates the insulation lever away from the second conductor 7 .

As the insulation lever is operated, the fifth conductor 51A rotates clockwise around the support shaft S1, and the sixth conductor 51B moves away from the second conductor 7. As shown in FIG. At the same time, the tenth conductor 54D protrudes from the hole 51C of the sixth conductor 51B by the elastic force of the spring body 55. As shown in FIG.

===Summary===
As described above, the disconnecting switch 5 according to the present embodiment includes the first conductor 6 connected to the primary side of the transformer 1, the second conductor 7 provided upstream of the first conductor 6, In order to open and close the electric circuit between the third conductor 51 rotatably supported with respect to the first conductor 6, the fuse 52 interposed in the electric circuit of the third conductor 51, the resistor 53, and the third When connecting the third conductor 51 to the second conductor 7, the resistor 53 is connected in series with the fuse 52 by contacting the second conductor 7 before the third conductor 51, and then the third conductor 51 is connected in series. and a fourth conductor 54 that short-circuits the resistor 53 by contacting the second conductor 7 .

In addition, in the present embodiment, the third conductor 51 includes a fifth conductor 51A closer to the first conductor 6 than the fuse 52 and a sixth conductor 51B closer to the second conductor 7 than the fuse 52. One end of the fourth conductor 54 is rotatably supported with respect to the sixth conductor 51B, and the other end of the fourth conductor 54 is connected to the hole 51C formed in the sixth conductor 51B. The resistor 53 is slidably inserted in the direction of the second conductor 7 while being insulated from 51B, and the resistor 53 is interposed in the electric path of the fourth conductor 54 .

Further, in this embodiment, an insulator made of a rubber member, a resin member, or the like is provided on the outer peripheral surface of the other end of the fourth conductor 54 or the inner peripheral surface of the hole 51C.

In addition, in the present embodiment, the third conductor 51 includes a fifth conductor 51B closer to the first conductor 6 than the fuse 52 and a sixth conductor 51B closer to the second conductor 7 than the fuse 52. The fourth conductor 54 includes a seventh conductor 54A rotatably supported with respect to the sixth conductor 51B, and a 7th conductor 54A rotatably supported with respect to the seventh conductor 54A. and an eighth conductor 54B slidably inserted in the hole 51C in the direction of the second conductor 7 while being insulated from the sixth conductor 51B. It intervenes in the electric path of the conductor 54A or the eighth conductor 54B.

Further, in this embodiment, an insulator made of a rubber member, a resin member, or the like is provided on the outer peripheral surface of the eighth conductor 54B or the inner peripheral surface of the hole 51C.

Further, in this embodiment, when the third conductor 51 is not connected to the second conductor 7, the sixth conductor 51B and the second conductor 7 are arranged so that the eighth conductor 54B protrudes in the direction of the second conductor 7 through the hole 51C. A spring body 55 that elastically urges between the seventh conductors 54A is further provided.

In this embodiment, the resistor 53 is a coil spring that is interposed in the electric path of the eighth conductor 54B and elastically urges the sixth conductor 51B and the seventh conductor 54A to approach each other.

According to this embodiment, by providing a simple mechanical structure, it is possible to protect the fuse 52 from a rush current that occurs when the power is turned on. Also, the life of the fuse 52 can be extended. Also, by setting the capacity of the fuse 52 to be small, it is possible to reliably cut off the current immediately after the occurrence of an accident in the transformer 1 .

It should be noted that the above-described embodiments are intended to facilitate understanding of the present invention, and are not intended to limit and interpret the present invention. The present invention may be modified and improved without departing from its spirit, and the present invention also includes equivalents thereof.

1 transformer 2 rectifier circuit 3 smoothing capacitor 4 load 5 disconnecting switch 6 first conductor 7 second conductor 51 third conductor 51A fifth conductor 51B sixth conductor 52 fuse 53 resistor 54 fourth conductor 54A seventh conductor 54B eighth Conductor 54C Ninth conductor 54D Tenth conductor 55 Spring bodies S1, S2, S3 Spindle

Claims (6)

A disconnecting switch for opening and closing an electric circuit between a first conductor connected to the primary side of a transformer and a second conductor provided upstream of the first conductor,
a third conductor rotatably supported with respect to the first conductor for opening and closing an electric path between the first conductor and the second conductor;
a fuse interposed in the electric path of the third conductor;
a resistor;
When connecting the third conductor to the second conductor, the resistor is connected in series with the fuse by contacting the second conductor before the third conductor, and then the third conductor. a fourth conductor shorting the resistor by contacting the second conductor;
with
the third conductor comprises a fifth conductor closer to the first conductor than the fuse and a sixth conductor closer to the second conductor than the fuse;
one end of the fourth conductor is rotatably supported with respect to the sixth conductor;
the other end of the fourth conductor is slidably inserted into a hole formed in the sixth conductor toward the second conductor while being insulated from the sixth conductor;
The resistor is interposed in the electric path of the fourth conductor
A disconnector characterized by: The disconnecting switch according to claim 1 , further comprising an insulator provided on the outer peripheral surface of the other end of the fourth conductor or the inner peripheral surface of the hole. the third conductor comprises a fifth conductor closer to the first conductor than the fuse and a sixth conductor closer to the second conductor than the fuse;
The fourth conductor includes a seventh conductor rotatably supported with respect to the sixth conductor, and a hole formed in the sixth conductor rotatably supported with respect to the seventh conductor. and an eighth conductor that is slidably inserted in the direction of the second conductor while being insulated from the sixth conductor,
The disconnecting switch according to claim 1, wherein the resistor is interposed in the electric circuit of the seventh conductor or the eighth conductor. The disconnecting switch according to claim 3 , further comprising an insulator provided on the outer peripheral surface of the eighth conductor or the inner peripheral surface of the hole. between the sixth conductor and the seventh conductor so that the eighth conductor protrudes in the direction of the second conductor through the hole when the third conductor is not connected to the second conductor; 4. The disconnecting switch according to claim 3 , further comprising an elastically biasing spring body. The resistor is interposed in the electric path of the eighth conductor,
The disconnecting switch according to claim 5 , wherein the spring body is a coil spring that elastically urges the sixth conductor and the seventh conductor to approach each other.

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