JP2023044401A - circuit breaker - Google Patents

Abstract

To provide a circuit breaker capable of reducing the influence of electromagnetic repulsion that slows down the opening speed of a movable contact without requiring an additional component such as a magnetic shield material.SOLUTION: A circuit breaker includes a handle operated by a user, a crossbar that rotates in conjunction with the operation of the handle, a fixed contact having a fixed contact point, a flat plate-shaped movable contact in which a movable contact point provided at one end in conjunction with the movement of the crossbar contacts and separates from a fixed contact point, and has a connecting portion on the other end side from the portion sandwiched between the crossbars, and rotates around the portion as a rotation axis, a flexible conductor having one end electrically connected to the power supply side terminal and the other end connected to the connecting portion of the movable contact, a contact pressure spring that biases the rotation of the movable contact when the movable contact point and the fixed contact point are in contact, and has one end connected to the side of the movable contact that has the connecting portion from the rotation shaft of the movable contact and the other end connected to the crossbar.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to circuit breakers.

In conventional circuit breakers, there is a method of covering the peripheral surface of the flexible lead wire with a porcelain shielding material, etc., in order to reduce the influence of the electromagnetic force acting in the direction of decelerating the opening speed of the movable contact. . For example, by arranging a straight movable contact and a flexible conductor in a U shape and covering the peripheral surface of the flexible conductor with a magnetic shielding material, electromagnetic repulsion that reduces the opening speed of the movable contact Techniques have been disclosed for reducing the effects of forces. (For example, see Patent Document 1)

JP 2011-187415 A

In the above-described circuit breaker in which the linear movable contact and the flexible conductor are arranged in a U shape, the flexible conductor is provided with a Additional parts such as magnetic shielding materials are required.

The present disclosure has been made to solve the above-described problems, and aims to reduce the effect of electromagnetic repulsion that slows down the opening speed of the movable contact without the need for additional parts. .

A circuit breaker according to the present disclosure includes a handle operated by a user, a crossbar that rotates in conjunction with the operation of the handle, a fixed contact having a fixed contact, and one end in conjunction with the operation of the crossbar. A flat plate-shaped movable contact that has a connecting portion on the other end side from a portion sandwiched by the crossbar and rotates about the portion as a rotation axis; A flexible conductor, one end of which is electrically connected to a power supply side terminal and the other end of which is connected to a connecting portion of a movable contact, and one end of which is movable and which biases the movable contact to rotate when the movable contact and the fixed contact are in contact with each other. A contact pressure spring is connected to a side having a connecting portion from the rotating shaft of the contact, and the other end is connected to the crossbar.

According to the circuit breaker of the present disclosure, it is possible to reduce the influence of the electromagnetic repulsive force that slows down the opening speed of the movable contact without requiring an additional component such as a magnetic shield material.

FIG. 2 is a side view showing the main configuration of the circuit breaker in the open state according to the first embodiment of the present disclosure; FIG. 2 is a side view of the circuit breaker according to the first embodiment of the present disclosure, viewed from the side opposite to FIG. 1 , showing the main configuration in the open state; FIG. 2 is a side view showing the main configuration of the circuit breaker in the closed state according to the first embodiment of the present disclosure; 2 is an enlarged view corresponding to part A of FIG. 1 according to the first embodiment of the present disclosure; FIG. FIG. 4 is an enlarged view corresponding to part B of FIG. 3 according to the first embodiment of the present disclosure; FIG. 10 is a side view showing the main configuration of the circuit breaker in the open state according to the second embodiment of the present disclosure; FIG. 10 is a side view showing the main configuration of the circuit breaker in the closed state according to the second embodiment of the present disclosure; FIG. 10 is a side view showing the main configuration of the circuit breaker according to the second embodiment of the present disclosure in an overrun state;

Embodiments will be described in detail below with reference to the drawings. In addition, the embodiment described below is an example. Also, each embodiment can be executed in combination as appropriate.

Embodiment 1.
The circuit breaker of the present disclosure has a size that conforms to the dimensions specified in the agreement-type circuit breaker used for light distribution boards, etc. according to Japanese Industrial Standards JIS C 8201-2-1: 2011 Annex JC. It was made to

FIG. 1 is a side view showing the essential configuration of the circuit breaker according to the first embodiment of the present disclosure in the open state, and FIG. 2 shows the essential configuration of the circuit breaker according to the first embodiment of the present disclosure in the open state. FIG. 3 is a right side view showing the main configuration of the circuit breaker according to the first embodiment of the present disclosure in the closed state, and FIG. 4 is an embodiment of the present disclosure 1, and FIG. 5 is an enlarged view corresponding to the B part of FIG. 4 according to the first embodiment of the present disclosure.

1 and 2 are configuration diagrams of a circuit breaker according to Embodiment 1 of the present disclosure. The circuit breaker shown in FIG. The movable contact 8a provided at one end interlocks with the movement and contacts and separates from the fixed contact 9a. A flat plate-shaped movable contact 8 that rotates around a rotary shaft 13a, and a flexible conductor 7 electrically connected to a power supply terminal 5 on one side and connected to a connecting portion 8d of the movable contact 8 on the other side. , which urges the rotation of the movable contact 8 when the movable contact 8a and the fixed contact 9a are in contact with each other. and a contact pressure spring 2 connected to 13 .

The handle 4 is operated by the user to open or vice versa the circuit breaker. The latch portion 16 rotates in conjunction with the handle 4 by the user's operation.

The crossbar 13 is rotatably supported by a pin 12a within the frame 12. As shown in FIG. When the user operates the handle 4, the crossbar 13 rotates in conjunction with the rotation of the latch portion 16. As shown in FIG.

The fixed contact 9 has a fixed contact 9 a and is arranged at a position facing the movable contact 8 . The stationary contact 9 is electrically connected to a load-side terminal 11 via a flexible conductor 10 with a film.

Description will be made with reference to FIG. The movable contact 8 has a flat plate shape having a movable contact 8a at one end and a connecting portion 8d at the other end. The movable contact 8 is divided into a lower portion 8f on the side of the movable contact 8a and an upper portion 8e on the side having the connecting portion 8d, with the pivot shaft 13a interposed between the crossbars 13 as a reference. The upper portion 8e side of the movable contactor 8, that is, the end portion of the side having the connection portion 8d, is bent, and the connection portion 8d connected to the flexible conductor 7 is provided at the bent portion. Since the end portion of the movable contact 8 on the connecting portion side is bent, it is easy to connect with the flexible conductor 7 at the connecting portion 8d. The flexible conductor 7, one end of which is connected to the movable contactor 8 at the connecting portion 8d, is connected to the power supply side terminal 5 fixed to the base 1 via the bimetal 6. As shown in FIG.

The movable contactor 8 is brought into contact with and separated from the fixed contact 9a in conjunction with the rotation of the crossbar 13. As shown in FIG. Contact with and separation from the fixed contact 9 a are performed by rotating the movable contact 8 in conjunction with the rotation of the crossbar 13 . A stopper 17 is provided on the base 1 and has a bent end at one end. The bent end of the stopper 17 receives the opening of the movable contactor 8 .

One end of the flexible conductor 7 is connected to a connecting portion 8 d provided at the bent portion of the movable contact 8 , and the other end is connected to the power supply side terminal 5 fixed to the base 1 via the bimetal 6 . The connecting portion 8d may be provided on the upper portion 8e side of the rotating shaft 13a of the movable contactor 8. As shown in FIG.

One end of the contact pressure spring 2 is connected to the side of the movable contactor 8 having the connection portion 8 d from the rotating shaft 13 a , and the other end is connected to the crossbar 13 . When the movable contact 8a and the fixed contact 9a contact and separate, the movable contact 8 is urged to rotate about the rotating shaft 13a.

The flexible conductor 7 and the movable contactor 8 are arranged so that the distance between them is smaller in the portion closer to the connection portion 8d than in the portion farther from the connection portion 8d. 4 and 5, when the distances between the flexible conductor 7 and the movable contact 8 are D1 and D2 in order of proximity to the connecting portion 8d, the flexible conductor 7 and the movable contact 8 are movable so that D1<D2. A contactor 8 is arranged. Further, it is easier to obtain the effect by arranging so that the closer to the connecting portion 8d, the closer the mutual distance is to the maximum, and the farther from the connecting portion 8d, the farther the mutual distance is to the maximum.

The opening operation of the circuit breaker will be described with reference to FIGS. 1 and 2. FIG.
When the user operates the handle 4 , the latch portion 16 rotates in conjunction with the operation of the handle 4 . As the latch portion 16 rotates, the crossbar 13, which is rotatably supported by the pin 12a in the frame 12, also rotates in conjunction with the rotation. stops rotating. Since the movable contactor 8 is pivotally supported by the crossbar 13 with the rotation shaft 13a, the rotation thereof stops when it comes into contact with the stopper 17. As shown in FIG. In this manner, the movable contactor 8 is stably held at the open position shown in FIGS.

Next, the contact operation of the circuit breaker will be described with reference to FIGS. 3 and 5. FIG.
When the user operates the handle 4 , the latch portion 16 rotates in conjunction with the operation of the handle 4 . As the latch portion 16 rotates, the crossbar 13 also rotates in conjunction with the latch portion 16 . A movable contactor 8 is attached to the crossbar 13 by a contact pressure spring 2, and the crossbar 13 is rotatably supported by a pin 12a in the frame. After the movable contact 8a and the fixed contact 9a are brought into contact with each other, the contact pressure spring 2 urges the upper portion 8e of the movable contact 8 on the side having the connecting portion 8d from the rotating shaft 13a toward the power supply side terminal 5. , the movable contact 8 uses the pivot shaft 13a as a fulcrum, and a force is applied toward the load side terminal 11 to the lower portion 8f of the movable contact 8 on the movable contact 8a side from the pivot shaft 13a. As a result, a further force is applied between the movable contact 8a and the fixed contact 9a, resulting in a closed state.

A long time delay tripping operation when a current larger than the rated current flows in the main circuit will be described.
In the closed state shown in FIG. 3, Joule heat is generated in the bimetal 6 due to the current flowing through the main circuit. However, when the current flowing through the main circuit becomes larger than the rated current, the bimetal 6 is overheated by the generated Joule heat and the temperature rises. When the temperature reaches a predetermined temperature, the bimetal 6 operates and bends, so that the tip of the bimetal 6 pushes the latch portion 16 toward the load-side terminal 11 . As a result, the crossbar 13 rotates counterclockwise. As the crossbar 13 rotates, the movable contactor 8 is opened from the fixed contactor 9 to enter the open state shown in FIGS. 1 and 2 and is stably held.

A short time delay tripping operation when an overcurrent flows in the main circuit will be described.
When an overcurrent flows through the main circuit in the closed state shown in FIG. One end side of the armature 14 is attracted and the armature 14 rotates counterclockwise. As the rotation progresses, the other end of the armature 14 pushes the latch portion 16, causing the crossbar 13 to rotate counterclockwise. As the crossbar 13 rotates, the movable contactor 8 is opened from the fixed contactor 9 to enter the open state shown in FIGS. 1 and 2 and is stably held.

Next, the instantaneous tripping operation when a large short-circuit current flows in the main circuit will be described.
When a large short-circuit current flows in the main circuit when the circuit breaker shown in FIGS. Since the currents flow in opposite directions, the magnetic fields generate forces in the repelling directions between the two. Regarding the arrows shown in FIG. 6 , the direction of force between the flexible conductor 7 and the movable contact 8 is indicated by a dashed line, and the direction of force between the movable contact 8 and the fixed contact 9 is indicated by a solid line. Also, the length of each arrow simulates the magnitude of the force.

4 and 5, the repulsive force between the flexible conductor 7 and the movable contact 8 indicated by the dashed line is generated in the direction of opening the flexible conductor 7 and in the direction of closing the movable contact 8. . Since the repulsive force acting in the closing direction of the movable contact 8 is a force in the opposite direction to the force that opens the movable contact 8 from the fixed contact 9, it is a force that prevents the opening of the movable contact 8. Become.

Therefore, in the present embodiment, the movable contact 8 is sandwiched between the crossbars 13, and the connecting portion between the flexible conductor 7 and the movable contact 8 is positioned further than the rotating shaft 13a serving as a fulcrum for rotating during contact and separation. By providing the contact 8d at one end opposite to the movable contact 8a, the influence of the electromagnetic repulsion between the flexible conductor 7 and the movable contact 8, which hinders the opening of the movable contact 8, is reduced. A specific description will be given below.

When a large short-circuit current flows through the main circuit when the circuit breaker is closed, current flows in opposite directions between the flexible conductor 7 and the movable contact 8 and between the movable contact 8 and the fixed contact 9, respectively. As they flow, their magnetic fields generate forces in the repelling directions between them. The repulsive force generated between the flexible conductor 7 and the movable contact 8 acting on the movable contact 8 in the closing direction is also applied in the closing direction to the upper part 8 e and the lower part 8 f of the movable contact 8 . force acts. However, the force acting on the upper portion 8e acts as a force that biases the lower portion 8f of the movable contact 8 in the opening direction through the rotating shaft 13a of the movable contact 8 according to the seesaw principle. . Therefore, the force that prevents the opening of the movable contactor 8 can be reduced by the repulsive force acting on the upper portion 8e of the movable contactor 8 acting as a force that promotes the opening through the rotating shaft 13a. .

In addition, the repulsive force generated between the movable contact 8 and the fixed contact 9 acts in the direction of contact opening, and is therefore a force that increases the opening speed of the movable contact 8 .

In this way, by providing the connecting portion 8d on the upper side 8e side of the rotating shaft 13a of the movable contact 8, the repulsive force generated between the flexible conductor 7 of the upper portion 8e and the movable contact 8 However, since this is a force that increases the opening speed of the movable contact 8, it is possible to reduce the effect of the electromagnetic repulsive force that slows down the opening speed of the movable contact.

Another example will be described with reference to FIG. As described above, the mutual distances between the flexible conductor 7 and the movable contact 8 are set to D1 and D2 in descending order from the connection portion 8d. By increasing D2, the repulsive force indicated by the dashed arrow that attenuates the opening speed of the movable contactor 8 decreases. On the other hand, by decreasing D1, the repulsive force between the flexible conductor 7 and the movable contact 8, which is generated between D1 and indicated by the dashed arrow, increases. As a result, the repulsive force generated in the upper portion 8e from the connecting portion 8d of the movable contact 8 to the rotating shaft 13a is applied to the lower portion 8f of the movable contact 8 via the rotating shaft 13a according to the seesaw principle. A force acts in the opening direction. Therefore, the repulsive force acting in the opening direction due to the seesaw principle is greater than the force shown by the dashed arrow generated between D2, so that the opening speed of the movable contact 8 is increased. acts on

A repulsive force acting between the movable contact 8 and the fixed contact 9 is indicated by solid arrows in FIG. Since the repulsive force acting on the lower portion 8f of the movable contact 8 acts toward the power source terminal 5, it is a force that increases the speed at which the movable contact 8 opens.

In this way, by arranging the flexible conductor 7 and the movable contactor 8 so that the distance between them is smaller in the portion closer to the connecting portion 8d than in the portion farther from the connecting portion 8d, the repulsive force acting on the lower portion 8f in the closing direction is small, and the repulsive force acting on the upper portion 8e in the closing direction can be increased. Since the repulsive force acting on the upper portion 8e in the closing direction acts on the lower portion 8f via the rotating shaft 13a as a repulsive force in the opening direction, the electromagnetic repulsion that decelerates the opening speed of the movable contact. It becomes easier to obtain the effect of reducing the influence of force.

As described above, the connection portion 8d between the flexible conductor 7 and the movable contactor 8 has the movable contactor 8 sandwiched between the crossbars 13, and is closer to the movable contact than the rotating shaft 13a serving as a fulcrum for rotating during contact and separation. By providing it on the one end side opposite to 8a, it is possible to reduce the influence of the electromagnetic repulsive force that slows down the opening speed of the movable contact without requiring an additional part such as a magnetic shield material.

Embodiment 2.
In the circuit breaker of the first embodiment, the stopper 17 is provided for stably stopping the movable contact 8 when the movable contact 8 is moved from the closed state to the open state. 2, the stopper 17 is made of an elastic member, and when the movable contactor 8 is operated from the closed state to the open state, it overruns to a position further separated from the normal open state position. It is a thing.

FIG. 6 is a side view showing the essential configuration of the circuit breaker according to the second embodiment of the present disclosure in the open state, and FIG. 7 shows the essential configuration of the circuit breaker according to the second embodiment of the present disclosure in the closed state. FIG. 8 is a side view showing the main configuration of the circuit breaker according to the second embodiment of the present disclosure in an overrun state.

As shown in FIG. 6, the stopper 17a in this embodiment is made of an elastic member and is held at one end by a rib 18 provided on the base 1. As shown in FIG. The tip of the other end of the stopper 17a is bent so as to receive the movable contact 8. As shown in FIG. Since the rest of the configuration is the same as that of the first embodiment, description thereof is omitted.

Next, the opening operation of the movable contactor 8 will be described.
When the opening operation is performed from the closed state shown in FIG. 7, the movable contactor 8 further overruns from the open state shown in FIG. 6 and opens to the state shown in FIG. 8 in which the contact distance increases. At this time, the movable contact 8 abuts against the stopper 17a, but since the stopper 17a is made of an elastic member, it bends in the direction of the flexible conductor 7, and the movable contact 8 once passes the open state shown in FIG. state, and then returns to the open state shown in FIG.

In this manner, the connecting portion 8d between the flexible conductor 7 and the movable contactor 8 is movable relative to the rotating shaft 13a, which serves as a fulcrum for rotating the movable contactor 8 between the crossbars 13 during contact and separation. An embodiment in which the effect of the electromagnetic repulsion that slows down the opening speed of the movable contact can be reduced without the need for additional parts such as a magnetic shielding material by providing the contact on the side opposite to the contact 8a. In addition to the same effects as in 1, the separation distance between the movable contact 8a and the fixed contact 9a can be increased when the movable contactor 8 is opened, so that the breaking performance can be improved.

In addition, if the stopper 17a is made of a metal plate spring and is provided above the arc-extinguishing chamber, and if a metal plate is provided below the arc-extinguishing chamber, it is possible to form an arc running path. Breaking performance can be further improved.

1 base, 2 contact pressure spring, 4 handle, 5 power supply side terminal, 6 bimetal, 7 flexible conductor, 8 movable contact, 8a movable contact, 8d connecting part, 8e upper part, 8f lower part, 9 fixed contact , 9a fixed contact, 10 coated flexible conductor, 11 load side terminal, 12 frame, 12a pin, 12b one end, 13 crossbar, 13a rotating shaft, 14 armature, 14a armature pin, 15 yoke, 16 latch portion, 17, 17a stopper, 18 rib

Claims (4)

a handle operated by a user;
a crossbar that rotates in conjunction with the operation of the handle;
a fixed contact having a fixed contact;
A movable contact provided at one end contacts and separates from the fixed contact in conjunction with the operation of the crossbar, and has a connecting portion on the other end side of the portion sandwiched between the crossbars to rotate the portion. a flat plate-shaped movable contact that rotates as an axis;
a flexible conductor having one end electrically connected to a power supply side terminal and the other end connected to the connecting portion of the movable contact;
When the movable contact and the fixed contact are in contact with each other, the movable contact is urged to rotate. One end of the movable contact is connected to the side of the movable contact having the connecting portion from the rotating shaft, and the other end is the crossbar. a contact pressure spring connected to
circuit breaker. 2. The circuit breaker according to claim 1, wherein the movable contact has a bent portion at the end on the side having the connecting portion, and the connecting portion is provided on the bent portion. 3. The circuit according to claim 1, wherein the distance between the flexible conductor and the movable contact is arranged so that a portion closer to the connecting portion is smaller than a portion farther from the connecting portion. circuit breaker. 4. The circuit breaker according to any one of claims 1 to 3, further comprising a stopper made of an elastic member for stopping the movement of the movable contact when the movable contact and the fixed contact are separated. vessel.

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