阅读说明：本技术 电路断路器 (Circuit breaker ) 是由 上青木大 于 2021-05-21 设计创作，主要内容包括：电路断路器(100)具有手柄(2)、卡合销(3)、第1臂(4)、弹键(5)、弹键弹簧(6)、可动件(7)、固定件(8)、消弧室(10)、电弧滚环(11)、电磁铁部(13)和第2臂(14)。电磁铁部(13)在电路中流过短路电流的情况下对致动器(13g)进行驱动。第2臂(14)在致动器(13g)被驱动的情况下对抗由弹键弹簧(6)产生的弹键(5)的预紧力而驱动弹键(5),将卡合销(3)和第1臂(4)的卡合解除。而且,第2臂(14)以旋转轴(15)为中心进行旋转,向弹键(5)的抵接位置和旋转轴(15)之间的距离比通过致动器(13g)的驱动而被按压的位置和旋转轴(15)之间的距离更长。(The circuit breaker (100) is provided with a handle (2), a clamping pin (3), a 1 st arm (4), a latch (5), a latch spring (6), a movable piece (7), a fixed piece (8), an arc extinguishing chamber (10), an arc rolling ring (11), an electromagnet part (13) and a 2 nd arm (14). The electromagnet section (13) drives the actuator (13g) when a short-circuit current flows through the circuit. When the actuator (13g) is driven, the 2 nd arm (14) drives the latch (5) against the biasing force of the latch (5) by the latch spring (6), and releases the engagement between the engagement pin (3) and the 1 st arm (4). The 2 nd arm (14) rotates around a rotation shaft (15), and the distance between the position of contact with the latch (5) and the rotation shaft (15) is longer than the distance between the position pressed by the drive of the actuator (13g) and the rotation shaft (15).)

1. A circuit breaker, comprising:

a handle operated by a user;

an engagement pin rotatably attached to the handle;

a 1 st arm that engages with the engagement pin and is linked with the movement of the engagement pin;

a latch for holding the engagement between the 1 st arm and the engagement pin;

a latch spring that biases the latch in a direction in which the latch holds the engagement between the 1 st arm and the engagement pin;

a movable element attached to the 1 st arm and having a movable contact;

a fixed member having a fixed contact point contacting the movable contact point;

an arc extinguishing chamber that extinguishes an arc generated between the movable contact and the fixed contact when the movable contact is separated from the fixed contact;

an arc runner for moving the arc toward the arc extinguishing chamber;

an electromagnet unit that drives the actuator when a short-circuit current flows through the circuit; and

a 2 nd arm that drives the latch against a biasing force of the latch by the latch spring when the actuator is driven, and releases the engagement between the engagement pin and the 1 st arm,

the 2 nd arm rotates about a rotation axis, and a distance between an abutment position of the latch and the rotation axis is longer than a distance between a position pressed by the actuator and the rotation axis.

2. The circuit breaker of claim 1,

the 2 nd arm is formed of an insulating member.

3. The circuit breaker according to claim 1 or 2,

the 2 nd arm has:

an extension portion, a middle portion of which is rotatably supported on the rotating shaft; and

an abutting portion continuous with the extending portion and abutting against the latch,

the contact portion is opposed to the movable contact and the fixed contact.

4. The circuit breaker of claim 3,

the contact portion is formed in a concave shape with respect to the surfaces of the movable contact and the fixed contact.

5. Circuit breaker according to claim 3 or 4,

the length of the contact portion in the extending direction of the rotating shaft is longer than the length of the movable contact and the length of the fixed contact.

6. The circuit breaker according to any one of claims 3 to 5,

the length of the contact portion in the extending direction of the rotating shaft is 0.9 times or more the length of the circuit breaker in the extending direction of the rotating shaft.

Technical Field

The present invention relates to a circuit breaker that opens a circuit when a short-circuit current flows.

Background

There is known a circuit breaker that performs a breaking operation of breaking a circuit when a large current such as a short-circuit current flows through the circuit. In this circuit breaker, it is required to rapidly separate the movable contact from the fixed contact during the breaking operation and to eliminate the arc generated between these contacts.

In a conventional circuit breaker, in order to quickly separate a movable contact from a fixed contact at the time of a breaking operation, the conventional circuit breaker is generally configured to have an electromagnet portion for driving an actuator by the large current. In the circuit breaker, the arc generated between the fixed contact and the movable contact is extinguished in the arc extinguishing chamber, but the arc needs to be guided to the arc extinguishing chamber. As a method of guiding an arc to an arc extinguishing chamber, a method of surrounding the periphery of a contact with an arc extinguishing chamber and an arc traveling method of moving an arc generated between contacts to an arc extinguishing chamber located at a distant position are known.

In the case of a small-sized circuit breaker often used for a distributor or the like, a configuration using both an electromagnet portion and an arc travel system is generally used as in the circuit breaker described in patent document 1 due to limitations in cost, outer dimensions, and the like.

Patent document 1: japanese laid-open patent publication No. 7-226143

In the circuit breaker using the arc traveling system, since there is no arc extinguishing chamber for extinguishing an arc in the periphery of the contact, it is preferable to further increase the separation speed and separation distance of the contacts in order to rapidly move the arc generated at the time of the breaking operation from the contact portion to the arc extinguishing chamber.

Disclosure of Invention

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a circuit breaker capable of further increasing the separation speed and separation distance of contacts during a breaking operation.

In order to solve the above problems and achieve the object, a circuit breaker according to the present invention includes a handle, an engaging pin, a 1 st arm, a latch spring, a movable member, a fixed member, an arc extinguishing chamber, an arc runner, an electromagnet portion, and a 2 nd arm. The handle is operated by the user. The engagement pin is rotatably attached to the handle. The 1 st arm is engaged with the engaging pin and interlocked with the movement of the engaging pin. The latch holds the 1 st arm and the engagement pin engaged with each other. The latch spring biases the latch in a direction in which the latch holds the engagement between the 1 st arm and the engagement pin. The movable element is attached to the 1 st arm and has a movable contact. The fixed member has a fixed contact point that contacts the movable contact point. The arc extinguishing chamber extinguishes an arc generated between the movable contact and the fixed contact when the movable contact is separated from the fixed contact. The arc runner moves the arc toward the arc extinguishing chamber. The electromagnet portion drives the actuator when a short-circuit current flows through the circuit. When the actuator is driven, the 2 nd arm drives the latch against the biasing force of the latch by the latch spring to release the engagement between the engagement pin and the 1 st arm. The 2 nd arm rotates about the rotation axis, and the distance between the position of abutment to the latch and the rotation axis is longer than the distance between the position pressed by the driving of the actuator and the rotation axis.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, the contact separation speed and the contact separation distance can be further increased during the circuit breaking operation.

Drawings

Fig. 1 is a diagram showing an example of an internal configuration in a case where the circuit breaker according to embodiment 1 is in a closed state.

Fig. 2 is a diagram showing an example of the structure of an electromagnet portion according to embodiment 1

Fig. 3 is a side view showing an example of the structure of the 2 nd arm according to embodiment 1

Fig. 4 is a front view showing an example of the structure of the 2 nd arm according to embodiment 1

FIG. 5 is a sectional view taken along line V-V of FIG. 4

Fig. 6 is a diagram showing an example of an internal configuration in a case where the circuit breaker according to embodiment 1 is in an open state

Fig. 7 is a perspective view showing an example of an internal configuration in a case where the circuit breaker according to embodiment 1 is in an open state

Detailed Description

Hereinafter, a circuit breaker according to an embodiment will be described in detail with reference to the drawings.

Embodiment 1.

Fig. 1 is a diagram showing an example of an internal configuration in a case where the circuit breaker according to embodiment 1 is in a closed state. In fig. 1, a 3-dimensional orthogonal coordinate system including a Z axis in which an upper direction on a paper surface is a positive direction is illustrated for ease of understanding of the description. The orthogonal coordinate system is also shown in other drawings used in the following description, and when only a part of the structure of the circuit breaker is illustrated, each direction of the X-axis, the Y-axis, and the Z-axis is a state shown in fig. 1, that is, a direction in a state where the circuit breaker is assembled. Hereinafter, the Z-axis direction may be referred to as the vertical direction, the positive Z-axis direction may be referred to as the vertical direction, and the positive X-axis direction may be referred to as the vertical direction.

The circuit breaker 100 shown in fig. 1 is configured to be switched from a closed state to an open state by a current breaking operation when a short-circuit current or an overcurrent flows through an electric circuit. The closed state is a state in which the circuit breaker 100 connects the circuit, and is a state in which current flows in the circuit. The open state is a state in which the circuit breaker 100 opens the circuit, and is a state in which current does not flow in the circuit.

The circuit breaker 100 includes a housing 1, a handle 2, an engaging pin 3, a 1 st arm 4, a latch 5, a latch spring 6, a movable element 7, a fixed element 8, a main spring 9, an arc extinguishing chamber 10, an arc runner 11, an overload detecting device 12, an electromagnet portion 13, and a 2 nd arm 14.

The housing 1 is formed of an insulating member and has an opening 1a on a front surface thereof. The handle 2 is operated by a user to change the circuit breaker 100 from the open state to the closed state or from the closed state to the open state. The handle 2 has: an operating portion 2a protruding from the opening 1 a; a rotating portion 2c that rotates about the rotating shaft 2b by a user's operation on the operating portion 2 a; and a projection 2d projecting from the rotation portion 2 c.

The engagement pin 3 is rotatably attached to the protruding portion 2d of the handle 2. The engaging pin 3 is formed in a U shape, for example, and is also called a U pin. The shape of the engagement pin 3 is not limited to the U-shape. The 1 st arm 4 is rotatably supported by a frame fixed to the frame 1, and a base end portion thereof is engaged with the engagement pin 3. The 1 st arm 4 is interlocked with the movement of the engagement pin 3 in a state where the base end portion is engaged with the engagement pin 3.

The latch 5 has: a holding portion 5a for holding the engagement between the 1 st arm 4 and the engagement pin 3; and an abutting portion 5b abutting against the 2 nd arm 14, the latch 5 being rotatably supported by a frame fixed to the housing 1. The latch spring 6 biases the latch 5 in a direction in which the latch 5 holds the engagement between the 1 st arm 4 and the engagement pin 3. The direction in which the latch spring 6 biases the latch 5 is the counterclockwise direction in fig. 1.

The base end of the movable element 7 is fixedly attached to the tip end of the 1 st arm 4, and the tip end has a movable contact 7 a. The stator 8 has a fixed contact 8a that contacts the movable contact 7 a. In the example shown in fig. 1, the movable element 7 is formed in a crank shape. The base end of the fixed contact 8a is fixedly attached to the electromagnet portion 13, and the tip end is formed in a U shape.

The main spring 9 pretensions the 1 st arm 4 clockwise in fig. 1. In the state shown in fig. 1, the handle 2 is at a position for controlling the circuit breaker 100 to be in the closed state, and the 1 st arm 4 and the engaging pin 3 are engaged with each other by the holding portion 5a of the latch 5, so that the movable contact 7a and the fixed contact 8a are brought into contact, and the circuit breaker 100 is in the closed state.

The arc extinguishing chamber 10 extinguishes an arc generated between the movable contact 7a and the fixed contact 8a when the movable contact 7a is separated from the fixed contact 8 a. The arc runner 11 moves an arc generated between the movable contact 7a and the fixed contact 8a toward the arc extinguishing chamber 10.

The overload detecting means 12 is constituted by, for example, a bimetal, and bends by self-heating if an overcurrent flows, and acts on the latch 5 if the bending reaches a predetermined amount, and the movable contact 7a separates from the fixed contact 8a as described later.

The electromagnet portion 13 drives the actuator 13g when a short-circuit current flows through the circuit. The 2 nd arm 14 is interlocked with the action of the actuator 13 g. The structure and operation of the electromagnet portion 13 and the 2 nd arm 14 will be described in detail later.

When the circuit breaker 100 is in the open state, if the user rotates the handle 2 to a position at which the circuit breaker 100 is in the closed state, the 1 st arm 4 connected to the handle 2 via the engaging pin 3 rotates, and the movable element 7 rotates in accordance with the rotation of the 1 st arm 4. As a result, the movable contact 7a and the fixed contact 8a come into contact with each other, and the state shown in fig. 1 is obtained, and the electric circuit is closed. The circuit breaker 100 is in a closed state, and thus can flow a current in an electric circuit.

In addition, in the case where the circuit breaker 100 is in the state shown in fig. 1, if an overcurrent flows in the circuit, the overload detection apparatus 12 is bent by self-heating. When the amount of the bending reaches a predetermined amount, the latch 5 is actuated by a force exceeding the biasing force of the latch spring 6. Thereby, the engagement between the 1 st arm 4 and the engagement pin 3 is released, and the movable contact 7a is separated from the fixed contact 8a by the force of the main spring 9. Therefore, the circuit breaker 100 is in the open state.

When the circuit breaker 100 is in the state shown in fig. 1, if a short-circuit current flows through the circuit, the electromagnet portion 13 and the 2 nd arm 14 release the engagement between the 1 st arm 4 and the engagement pin 3, and the movable contact 7a is separated from the fixed contact 8a by the force of the main spring 9. Therefore, the circuit breaker 100 is in the open state. Next, the electromagnet portion 13 and the 2 nd arm 14 will be specifically described.

First, the electromagnet portion 13 will be explained. Fig. 2 is a diagram showing an example of the structure of the electromagnet portion according to embodiment 1. As shown in fig. 2, the electromagnet portion 13 includes a coil 13a, yoke portions 13b and 13c, a tube 13d, a fixed core 13e, a movable core 13f, an actuator 13g, and a hook 13 h.

The yoke portions 13b and 13c are formed of a magnetic material, and the fixed core 13e and the movable core 13f are formed of a conductive member such as iron. One end of the actuator 13g is fixed to the movable core 13f, and one end of the hook 13h is fixed to the other end of the actuator 13 g.

As shown in fig. 2, the hook 13h is formed in an L shape. The hook 13h has: a 1 st extending portion 13h1 that extends in an upward direction, which is a direction perpendicular to the moving direction of the movable core 13f and is close to the handle 2; and a 2 nd extending portion 13h2 extending in the moving direction of the movable core 13f and in the direction away from the movable core 13 f. The 1 st extension 13h1 is fixed to the other end of the actuator 13 g.

The coil 13a is connected to the stator 8, and constitutes a part of an electric circuit between the power source side conductor and the load side conductor in the circuit breaker 100. If a short-circuit current flows through the coil 13a, a magnetic flux is generated.

The magnetic flux generated by the short-circuit current flowing through the coil 13a passes through the yoke portions 13b and 13c, and penetrates the fixed core 13e and the movable core 13f incorporated in the tube 13 d. Thereby, the fixed core 13e and the movable core 13f are magnetized, and the movable core 13f is attracted by the fixed core 13e and moves toward the fixed core 13 e. Further, as described above, since the actuator 13g is fixed to the movable core 13f and the hook 13h is fixed to the actuator 13g, the actuator 13g and the hook 13h also move toward the fixed core 13 e.

The movable core 13f is biased in a direction away from the fixed core 13e by biasing means, not shown, and the movable core 13f does not move toward the fixed core 13e when a large current is not applied and a magnetic force is generated in the coil 13 a. The biasing means, not shown, is, for example, a cylindrical coil spring or the like disposed in the tube 13 d.

Next, the structure of the 2 nd arm 14 will be explained. Fig. 3 is a side view showing an example of the structure of the 2 nd arm according to embodiment 1. Fig. 4 is a front view showing an example of the structure of the 2 nd arm according to embodiment 1. Fig. 5 is a sectional view taken along line V-V shown in fig. 4.

The 2 nd arm 14 shown in fig. 3 to 5 is formed of an insulating member such as resin, for example, but may be formed of a material other than the insulating member. The 2 nd arm 14 has an extended portion 14a and an abutting portion 14b, and rotates about a rotation axis 15 shown in fig. 1.

The extending portion 14a extends in the vertical direction when the circuit breaker 100 is in the closed state, and the middle portion is rotatably supported by the rotating shaft 15 shown in fig. 1. The base end portion of the extension portion 14a is rotatably connected to the hook 13h of the electromagnet portion 13. The distal end of the extending portion 14a is continuous with the proximal end of the abutting portion 14 b. The contact portion 14b has a shape expanding from the base end toward the tip end in the direction orthogonal to the extending direction of the rotary shaft 15, and is formed in a semicircular shape when viewed from the extending direction of the rotary shaft 15.

The contact portion 14b has a contact surface 14b1 that contacts the contact portion 5b of the latch 5 shown in fig. 1, and the contact surface 14b1 is formed in an arc shape. Further, a notch portion 14b2 is formed at the tip end of the contact portion 14b at a position facing the movable element 7. The cutout portion 14b2 is formed at the center of the distal end of the contact portion 14b in the extending direction of the rotating shaft 15. The contact portion 14b has a concave space 14c recessed upward therein. The length of the contact portion 14b in the extending direction of the rotating shaft 15 is longer than the length of the movable contact 7a and the fixed contact 8a in the extending direction of the rotating shaft 15.

Next, the operation of the electromagnet portion 13 and the 2 nd arm 14 will be described. Fig. 6 is a diagram showing an example of an internal configuration in a case where the circuit breaker according to embodiment 1 is in an open state.

When the circuit breaker 100 is in the state shown in fig. 1, if a short-circuit current flows through the circuit, the electromagnet portion 13 drives the actuator 13g, and the actuator 13g and the hook 13h move in the right direction in fig. 1. The 2 nd arm 14 is rotatably connected to the hook 13 h. Therefore, when the actuator 13g is driven, the 2 nd arm 14 rotates clockwise in fig. 1, and the latch 5 rotates clockwise in fig. 1 against the biasing force of the latch 5 by the latch spring 6.

Then, if the engagement between the 1 st arm 4 and the engagement pin 3 is released, the movable contact 7a is separated from the fixed contact 8a by the force of the main spring 9, and the circuit breaker 100 is in the open state as shown in fig. 6. Further, the cutout portion 14b2 is formed in the 2 nd arm 14 as described above, and the 2 nd arm 14 does not contact the movable element 7 when the 2 nd arm 14 is rotated by the cutout portion 14b 2.

As shown in fig. 6, the distance L2 between the contact position of the 2 nd arm 14 with the latch 5 and the rotation shaft 15 is longer than the distance L1 between the position pressed by the drive of the actuator 13g and the rotation shaft 15. Thereby, the latch 5 side of the 2 nd arm 14 can rotate the latch 5 at an operation speed faster than the operation speed of the movable core 13f by the electromagnet portion 13.

In the circuit breaker 100, even if the operation stroke of the actuator 13g of the electromagnet portion 13 is not increased, a large operation stroke can be generated at a position where the 2 nd arm 14 abuts against the latch 5. Since the 1 st arm 4 rotates in accordance with the rotation of the latch 5, the circuit breaker 100 can increase the moving distance of the 1 st arm 4 and the moving distance of the movable element 7 fixed to the 1 st arm 4. Therefore, in the circuit breaker 100, the distance separating the movable contact 7a and the fixed contact 8a can be increased without increasing the size of the electromagnet portion 13.

In the above example, the position pressed by the driving of the actuator 13g is the connection position of the hook 13h and the 2 nd arm 14, but the present invention is not limited to this example. For example, in the case of a configuration in which the 2 nd arm 14 is directly connected to the actuator 13g, the position pressed by the driving of the actuator 13g is the connection position of the actuator 13g and the 2 nd arm 14.

The 2 nd arm 14 may be configured to engage with the 1 st arm 4 when rotated clockwise in fig. 1 from the state shown in fig. 1. Thereby, the movable contact 7a can be separated from the fixed contact 8a by the rotational force of the 2 nd arm 14 in addition to the force of the main spring 9.

Fig. 7 is a perspective view showing an example of an internal configuration in a case where the circuit breaker according to embodiment 1 is in an open state. In fig. 7, an arc 16 generated between the movable contact 7a and the fixed contact 8a at the time of the breaking action is simply shown. As shown in fig. 7, the contact portion 14b of the 2 nd arm 14 is disposed so as to face the movable contact 7a and the fixed contact 8a, and covers the upper sides of the movable contact 7a and the fixed contact 8 a. Therefore, it is possible to suppress the arc gas or the melt generated during the circuit breaking operation from flying and adhering to the internal mechanisms such as the 1 st arm 4 and the latch 5, and to suppress the performance of the circuit breaker 100 after the short-circuit current is broken from decreasing.

When it is desired to prevent the adhesion of arc gas, molten material, or the like as much as possible, it is preferable that the 2 nd arm 14 is present until the positions of the movable element 7 and the fixed element 8 reach the limit, but when the 2 nd arm 14 is formed of metal, the insulation distance may be insufficient. By forming the 2 nd arm 14 from an insulating member, the 2 nd arm 14 can be held until the positions of the movable element 7 and the fixed element 8 reach the limit. Therefore, by forming the 2 nd arm 14 from an insulating member, adhesion of arc gas, molten material, or the like can be further suppressed as compared with a case where the 2 nd arm 14 is formed from metal.

In order to prevent the arc gas, the melt, and the like from flying to the internal mechanism by the 2 nd arm 14, the contact portion 14b of the 2 nd arm 14 is preferably the same size as the width of the inside of the circuit breaker 100 in the extending direction of the rotating shaft 15, but if it is completely the same, the 2 nd arm 14 cannot be rotated. Therefore, the length of the contact portion 14b of the 2 nd arm 14 in the extending direction of the rotary shaft 15 is preferably designed to be as close as possible to the width dimension of the inside of the circuit breaker 100 in a range not interfering with the rotational movement. The width dimension is a length in the extending direction of the rotation shaft 15. For example, the length of the contact portion 14b in the extending direction of the rotating shaft 15 is preferably set to be 0.9 times or more the length of the rotating shaft 15 in the extending direction inside the circuit breaker 100.

The contact portion 14b of the 2 nd arm 14 has a concave space 14c recessed upward therein, and the opposing surfaces 14d of the fixed contact 8a and the movable contact 7a are formed in a concave shape. This enables the 2 nd arm 14 to more effectively suppress the arc gas, the melt, and the like from flying toward the internal mechanism.

The 2 nd arm 14 is not limited to the shape shown in fig. 3 to 5 as long as it is a shape capable of suppressing the flying of the arc gas, the melt, or the like to the internal mechanism, and may be configured without the notch portion 14b2 and the concave space 14c, for example. For example, the 2 nd arm 14 may be configured to abut the 1 st arm 4 in addition to the latch 5, and rotate both the latch 5 and the 1 st arm 4.

As described above, the circuit breaker 100 according to embodiment 1 includes the handle 2, the engaging pin 3, the 1 st arm 4, the latch 5, the latch spring 6, the movable element 7, the fixed element 8, the arc extinguishing chamber 10, the arc runner 11, the electromagnet portion 13, and the 2 nd arm 14. The handle 2 is operated by a user. The engagement pin 3 is rotatably attached to the handle 2. The 1 st arm 4 engages with the engagement pin 3 and is interlocked with the movement of the engagement pin 3. The latch 5 holds the 1 st arm 4 and the engagement pin 3 in engagement with each other. The latch spring 6 biases the latch 5 in a direction in which the latch 5 holds the engagement between the 1 st arm 4 and the engagement pin 3. The movable element 7 is attached to the 1 st arm 4 and has a movable contact 7 a. The stator 8 has a fixed contact 8a that contacts the movable contact 7 a. The arc extinguishing chamber 10 extinguishes an arc 16 generated between the movable contact 7a and the fixed contact 8a when the movable contact 7a is separated from the fixed contact 8 a. The arc runner 11 moves towards the arc 16 towards the extinguishing chamber 10. The electromagnet portion 13 drives the actuator 13g when a short-circuit current flows through the circuit. When the actuator 13g is driven, the 2 nd arm 14 drives the latch 5 against the biasing force of the latch 5 by the latch spring 6, and releases the engagement between the engagement pin 3 and the 1 st arm 4. The 2 nd arm 14 rotates about the rotation shaft 15, and the distance L2 between the position of contact with the latch 5 and the rotation shaft 15 is longer than the distance L1 between the position pressed by the drive of the actuator 13g and the rotation shaft 15. Thus, in the circuit breaker 100, the contact separation speed and the contact separation distance can be further increased during the circuit breaking operation, and the current breaking performance in the circuit breaker 100 can be easily improved.

The 2 nd arm 14 is formed of an insulating member. Thus, in the circuit breaker 100, the 2 nd arm 14 can be located until the positions of the movable element 7 and the fixed element 8 reach the limit, and adhesion of arc gas, molten material, or the like can be further suppressed as compared with a case where the 2 nd arm 14 is formed of metal.

In addition, the 2 nd arm 14 has an extended portion 14a and an abutting portion 14 b. The middle portion of the extending portion 14a is rotatably supported by the rotating shaft 15. The contact portion 14b is continuous with the extension portion 14a and contacts the latch 5. The contact portion 14b faces the movable contact 7a and the fixed contact 8 a. Accordingly, in the circuit breaker 100, it is possible to suppress the arc gas or the melt generated during the breaking operation from flying and adhering to the internal mechanisms such as the 1 st arm 4 and the latch 5, and to suppress the performance of the circuit breaker 100 after the short-circuit current is broken from decreasing.

The contact portion 14b has a concave shape on its surface 14d facing the movable contact 7a and the fixed contact 8 a. This can more effectively suppress the arc gas, the melt, and the like from flying toward the internal mechanism in the circuit breaker 100.

The length of the contact portion 14b in the extending direction of the rotating shaft 15 is longer than the movable contact 7a and the fixed contact 8 a. This can more effectively suppress the arc gas, the melt, and the like from flying toward the internal mechanism in the circuit breaker 100.

The length of the contact portion 14b in the extending direction of the rotating shaft 15 is 0.9 times or more the length of the circuit breaker 100 in the extending direction of the rotating shaft 15. This can more effectively suppress the arc gas, the melt, and the like from flying toward the internal mechanism in the circuit breaker 100.

The configuration described in the above embodiment is an example, and may be combined with other known techniques, and a part of the configuration may be omitted or modified without departing from the scope of the invention.

Description of the reference numerals

1 frame, 1a opening, 2 handle, 2a operation part, 2b, 15 rotation shaft, 2c rotation part, 2d protrusion part, 3 engagement pin, 4 1 st arm, 5 latch, 5a holding part, 5b, 14b contact part, 6 latch spring, 7 movable piece, 7a movable contact, 8 fixed piece, 8a fixed contact, 9 main spring, 10 arc extinguishing chamber, 11 arc rolling ring, 12 overload detection device, 13 electromagnet part, 13a coil, 13b, 13c yoke part, 13d tube, 13e fixed iron core, 13f movable iron core, 13g actuator, 13h hook, 13h 11 extension part, 13h 22 extension part, 14 nd arm, 14a extension part, 1 contact surface, 14b2 notch part, 14c recess space, 14d opposite surface, arc 16, 100 circuit breaker.