JP7510212B2 - Circuit Breakers - Google Patents

Description

The present invention relates to a circuit breaker that protects equipment on the load side by interrupting a circuit connecting a power source and a load side when an overcurrent flows through the circuit.

As shown in Figures 7 to 9 of Patent Document 1, for example, the above circuit breaker includes a circuit connected to a terminal on the power supply side and a terminal on the load side, a movable contact and a fixed contact provided on the circuit, an opening/closing mechanism for switching the open/closed state of the movable contact and the fixed contact, a first core that is a magnetic material and becomes an electromagnet when a current flows through the circuit, a second core that is a magnetic material and is arranged opposite the first core with a space therebetween, and a strip-shaped bimetal that is arranged between the first core and the second core.

The opening and closing mechanism of the circuit breaker configured as above has an operating plate that can be latched to the first core, and switches the open and closed states of the movable contact and the fixed contact by switching the latched state to the first core.

In addition, in the circuit breaker with the above configuration, when the movable contact and the fixed contact are closed, the operating plate is hooked to the first core, but when the bimetal heats up due to an overcurrent flowing through the circuit, the bimetal bends toward the second core, and the first core moves toward the second core, releasing the hooking of the operating plate from the first core. This opens the movable contact and the fixed contact (so-called time-delay tripping is performed).

Furthermore, in a circuit breaker with the above configuration, even if an excessive current, such as a short-circuit current, flows through the circuit and generates a magnetic force in the first core, causing the first core to move toward the second core before the bimetal bends, the operating plate is released from the first core and the movable contact and fixed contact are opened (so-called instantaneous tripping is performed).

JP 2002-25415 A

In view of the above circumstances, an object of the present invention is to provide a circuit breaker that can more reliably interrupt a circuit when an abnormal current flows .

The circuit breaker of the present invention comprises:
Case and
A circuit connected to a terminal on the power supply side and a terminal on the load side;
A contact portion for opening and closing the circuit;
an attracting body which becomes an electromagnet by a current flowing through the circuit;
a movable body that can hold the contact portion in a closed state and is switchable between a holding state in which the contact portion is disposed opposite the attraction body with a gap therebetween to allow for movement of the contact portion toward the attraction body, and a release state in which the contact portion is released from the holding state against the closed state and can be opened when the movable body moves toward the attraction body and comes into contact with the attraction body;
The attraction body is configured to be movable in a direction opposite to the movable body,
a position of the attraction body in the opposing direction in the released state of the movable body is a position moved to the opposite side to the side where the movable body is disposed from a position of the attraction body in the held state of the movable body by rotating the attraction body relative to the case about an axis extending along a width direction perpendicular to the opposing direction and moving relative to the case in the opposing direction;
It is a circuit breaker.

As described above, the circuit breaker of the present invention has the excellent effect of suppressing plastic deformation of the bimetal.

FIG. 1 is a perspective view of a circuit breaker according to an embodiment of the present invention. FIG. 2 is an exploded view of the circuit breaker according to the embodiment. FIG. 3 is an enlarged view of the inside of a case of the circuit breaker according to the embodiment. FIG. 4 is an explanatory diagram of the mounting structure of the attraction body of the circuit breaker according to the embodiment. FIG. 5 is an explanatory diagram of a mounting structure of a movable body of the circuit breaker according to the embodiment. FIG. 6 is a view of the attraction body of the circuit breaker according to the embodiment as viewed from the movable body side. FIG. 7 is a view of the attraction body of the circuit breaker according to the embodiment as viewed from the front side of the case. FIG. 8 is a perspective view of a movable body of the circuit breaker according to the embodiment. FIG. 9 is a view of the movable body of the circuit breaker according to the embodiment as viewed from the front side of the case. FIG. 10 is an explanatory diagram of the operation of the circuit breaker according to the embodiment, illustrating a state in which the contact portion is closed. FIG. 11 is an explanatory diagram of the operation of the circuit breaker according to the embodiment, illustrating a state in which the contact portion is open. FIG. 12 is an explanatory diagram of the operation of the circuit breaker according to the embodiment, illustrating the attraction body and the movable body before the circuit is interrupted. In FIG. 13, (a) is an explanatory diagram of the attraction body and the movable body after the circuit is interrupted, and (b) is an explanatory diagram of the state in which the attraction body and the movable body have moved after the circuit is interrupted.

The following describes a circuit breaker according to one embodiment of the present invention with reference to the attached drawings.

A circuit breaker is used to protect equipment connected to the load side by cutting off the circuit when an abnormal current flows.

As shown in FIG. 1, the circuit breaker 1 includes a case (housing) 2, a circuit 3 that electrically connects the power supply side and the load side as shown in FIG. 2, an attracting body 4 that becomes an electromagnet when a current flows through the circuit 3, a movable body 5 that can hold the contact portion 31 in a closed state and can be switched between a holding state in which the attracting body 4 faces the attracting body 4 with a space for movement toward the attracting body 4, and a release state in which the contact portion 31 can be opened by moving toward the attracting body 4 and contacting the attracting body 4 to release the holding of the contact portion 31 in the closed state, a bimetal 6 that deforms when heated to move the movable body 5 toward the attracting body 4, a biasing member 7 (hereinafter referred to as a contact biasing member) that biases the attracting body 4 toward the movable body 5, and an operating mechanism 8 that can open and close the contact portion 31.

As shown in FIG. 1, the case 2 includes a front surface 20, which is a surface that is located on the near side when the circuit breaker 1 is attached to the distribution board, a back surface 21, which is a surface opposite the front surface 20 (a surface that is located opposite the surface that is attached to the distribution board during use), and a pair of side surfaces 22 that are continuous with the front surface 20 and the back surface 21 and are located opposite each other. The side surfaces 22 of the case 2 are surfaces that face the side surfaces 22 of the case 2 of another circuit breaker 1 when the circuit breaker 1 is installed in the distribution board.

In the following description of this embodiment, the direction in which the front 20 and back 21 of the case 2 are aligned is referred to as the front-to-rear direction, the direction in which the pair of side surfaces 22 are aligned is referred to as the width direction, and the direction perpendicular to both the front-to-rear direction and the width direction is referred to as the height direction.

As shown in FIG. 2, the circuit 3 has a pair of input terminals 30 connected to a distribution board, and a contact unit 31 capable of opening and closing an electrical circuit connecting the pair of input terminals 30. In addition, the circuit 3 is provided with one contact unit 31 for each input terminal 30.

In the following explanation, the state in which the contact portion 31 closes the electrical path (circuit) may be referred to as the closed state, and the state in which the contact portion 31 opens the electrical path (circuit) may be referred to as the open state.

Each contact portion 31 has a fixed terminal 310 that is fixed inside the case 2, and a movable terminal 311 that can be brought into contact with and separated from the fixed terminal 310.

The movable terminal 311 is made of a long, thin metal plate that can be elastically deformed. One end (base end) of the movable terminal 311 in the longitudinal direction is positioned (fixed) within the case 2.

The other end (tip) side in the longitudinal direction of the movable side terminal 311 is disposed at a distance from the fixed side terminal 310 on the near side in the front-rear direction when the contact portion 31 is switched to the open state. Therefore, the movable side terminal 311 is configured to bend (elastically deform) toward the fixed side terminal 310, so that the tip of the movable side terminal 311 abuts against the fixed side terminal 310 (i.e., the movable side terminal 311 is switched to the closed state).

The attracting body 4 is configured to generate a magnetic force according to the magnitude of the current flowing through the circuit. The attracting body 4 according to this embodiment has an attracting side facing surface 40 arranged facing the movable body 5. The attracting side facing surface 40 includes a contact portion (hereinafter referred to as the attracting side contact portion) 400 that contacts the movable body 5 (the movable side facing surface of the movable body 5 described later) on one side (the portion arranged on the side of the starting point (the rotation axis 220 described later) when the attracting body 4 moves) when the movable body 5 is in the holding state, and a contact-separation portion (hereinafter referred to as the attracting side contact-separation portion) 401 that can contact and separate from the movable body 5 (the movable side facing surface of the movable body 5 described later) on the other side.

As shown in FIG. 6, the suction body 4 according to this embodiment has a pair of side walls 41 that are spaced apart from each other in the width direction, and a connecting wall 42 that is connected to each of the pair of side walls 41.

The pair of side walls 41 are arranged so that they are parallel to each other with their wall surfaces facing the width direction. The suction side facing surface 40 is formed by the portion of the side walls 41 that is arranged toward the movable body 5.

The suction side opposing surface 40 is a flat surface, and in the normal state (when no action is being taken to switch from the holding state to the holding release state), it is inclined so that the suction side contact portion 401 is located farther from the movable body 5 in the vertical width direction than the suction side contact portion 400.

Furthermore, each of the pair of side walls 41 is rotatably attached to the inside of the side surface 22 of the case 2. More specifically, as shown in FIG. 4, each of the pair of side walls 41 is configured to be rotatable about an axis extending along the width direction. In this embodiment, a through hole 410 is formed in the side wall 41, and a rotation shaft 220 that protrudes from the inside of the side surface 22 of the case 2 toward the inside in the width direction is inserted into this through hole 410.

The through hole 410 is a round hole with a uniform or approximately uniform hole diameter around the entire circumference. The through hole 410 is formed at a position shifted from the suction side contact portion 400 to the other side, i.e., at a position shifted toward the suction side contact portion 401. In this embodiment, the through hole 410 is formed at a position shifted toward the suction side contact portion 401 from the center in the front-rear direction.

Here, we will explain the pivot shaft 220. At least the width of the tip of the pivot shaft 220 in the vertical width direction is smaller than the diameter of the through hole 410.

In this embodiment, the tip side of the pivot shaft 220 includes a guide surface 220a located on one side in the vertical width direction (the side opposite the movable body 5) and an escape surface 220b located on the other side in the vertical width direction (the side toward the movable body 5).

The guide surface 220a is arc-shaped. The curvature of the guide surface 220a is the same or approximately the same as the curvature of the through hole 410.

The escape surface 220b is formed so as to be located inside (towards the center of the pivot shaft 220) the extension line of the guide surface 220a.

As shown in FIG. 12, the escape surface 220b includes an arc-shaped curved surface 220ba located at the frontmost position in the vertical width direction, and a pair of inclined surfaces 220bb extending from both ends of the curved surface 220ba and continuing to the guide surface 220a, and the pair of inclined surfaces 220bb are inclined so as to face outward in the front-rear direction as they move from the curved surface 220ba side to the guide surface 220a side.

Therefore, when the guide surface 220a is in contact with the inner circumferential surface that defines the through hole 410 in the side wall portion 41, the pivot shaft 220 is configured so that a gap is formed between the escape surface 220b and the inner circumferential surface.

The suction body 4 can therefore rotate around the through hole 410 as the starting point (center) of rotation, and can also move in the width direction by the amount of the gap. When the entire suction body 4 rotates around the rotation shaft 220, the suction side contact portion 400 and the suction side approach/separation portion 401 rotate in the circumferential direction around the rotation shaft 220 inserted through the through hole 410.

Therefore, in the circuit breaker 1 according to this embodiment, an attachment structure for attaching the suction body 4 to the case 2 is configured by a case side engagement part formed by the pivot shaft 220 of the case 2 and a suction side engagement part formed by the through hole 410 of the suction body 4 and engaging with the case side engagement part, and further, the engagement position of the suction side engagement part is configured to change with respect to the case side engagement part in the direction of approaching and separating from the movable body 5.

As shown in FIG. 7, the connecting wall portion 42 is connected to the ends of each side wall portion 41 on the side opposite the movable body 5, and both the surface facing the movable body 5 (hereinafter referred to as the inner surface) and the surface facing the opposite side to the movable body 5 (hereinafter referred to as the outer surface) are flat.

As shown in FIG. 8, the movable body 5 has a movable side facing surface 50 that is arranged opposite the suction side facing surface 40.

This movable side opposing surface 50 includes a contact portion (hereinafter referred to as the movable side contact portion) 500 that contacts the suction side contact portion 400 when its state is switched to the holding state, and a contact-separation portion (hereinafter referred to as the movable side contact-separation portion) 501 that is arranged with a gap that allows it to contact and separate from the suction side contact-separation portion 401.

It is preferable that the suction side contact portion 400 and the movable side contact portion 500 are in point contact or approximately point contact.

The movable body 5 in this embodiment has a long, thin plate-like movable body main body part 51, an attachment part 52 that rotatably attaches the movable body main body part 51 to the case 2, and a push operation part 53 that is pushed toward the attracting body 4 by the bimetal 6.

The movable body main body 51 has one plate surface facing the suction body 4 and the other plate surface facing the opposite side to the suction body 4, and the one plate surface constitutes the movable side opposing surface 50.

In addition, the movable body main body 51 is normally positioned so that it extends straight along the front-to-rear direction, with the movable side contact portion 500 being formed by the area of one of the plate surfaces facing the back surface 21 of the case 2, and the movable side approach/separation portion 501 being formed by the area of one of the plate surfaces of the movable body main body 51 facing the front surface 20 of the case 2.

The movable body main body 51 is also formed with a hook retainer 54 that is used to keep the contact 31 in a closed state. The hook retainer 54 is a hole that penetrates from one plate surface to the other plate surface of the movable body main body 51, but may also be formed, for example, as a recess that opens only on the other plate surface side.

As shown in FIG. 5, the attachment portion 52 is connected to the end of the movable body main body 51 that is located on the rear surface 21 side of the case 2, and extends outward from both sides of the movable body main body 51 in the width direction. The attachment portion 52 is also rotatably inserted into a recessed receiving portion 221 formed on the inside of the side surface 22.

Furthermore, the attachment portion 52 is disposed at a position offset toward the rear surface 21 of the case 2 based on the contact position between the suction side contact portion 400 and the movable side contact portion 500. Therefore, the rotation starting point of the movable body 5 is also disposed at a position offset in the front-to-rear direction (a position offset toward the rear surface 21 of the case 2) with respect to the rotation starting point of the suction body 4. This allows the movable body 5 to rotate with the attachment portion 52 as the rotation starting point, moving the movable side contact-separation portion 501 toward and away from the suction side contact-separation portion 401.

As shown in FIG. 10, the bimetal 6 is heated by an overcurrent flowing through the circuit 3, and is formed so as to bend as a result of the heating. In this embodiment, the overcurrent refers to a current that heats the bimetal 6 so as to move the movable body 5 toward the attractor 4 as it deforms (the current that flows when performing so-called time-delay tripping), and the excessive current refers to a current that generates a magnetic force strong enough to attract the movable body 5 to the attractor 4 (the current that flows when performing so-called instantaneous tripping).

The bimetal 6 is in the form of a strip, with one side of the plate having a higher thermal expansion coefficient than the other side of the plate.

The bimetal 6 is disposed between the attracting body 4 and the movable body 5. More specifically, the bimetal 6 is disposed between a pair of side walls 41 of the attracting body 4, with one plate surface facing the movable body 5 and the other plate surface facing the connecting wall 42.

Of the two longitudinal ends of the bimetal 6, only one end 60 (hereinafter referred to as the fixed end) is fixed inside the case 2.

The other end (hereinafter referred to as the movable end) 61 of the two longitudinal ends of the bimetal 6 is disposed opposite the push operation part 53 of the movable body 5 in the vertical width direction. In addition, the movable end 61 of the bimetal 6 is disposed with the other plate surface side facing the push operation part 53 (see FIG. 9).

Therefore, when the bimetal 6 is heated by an overcurrent flowing through the circuit 3, the other plate surface bends and sinks in, and the movable end 61 pushes the push operation part 53 toward the attracting body 4.

The contact biasing member 7 is fixed in a position within the case 2 and is configured to bias the connecting wall portion 42 of the suction body 4 toward the movable body 5.

As shown in FIG. 3, the contact biasing member 7 is configured to bias the attraction body 4 toward the movable body 5 at a position shifted from the rotation starting point of the attraction body 4 toward the rotation starting point of the movable body 5 in the front-rear direction (in this embodiment, between the rotation starting point of the attraction body 4 and the rotation starting point of the movable body 5).

As a result, in the normal state, the suction body 4 is in an inclined position with the suction side contact portion 400 approaching the suction side contact-separation portion 401, and when the suction side contact portion 400 is pressed by the movable side contact portion 500, the suction side contact-separation portion 401 rotates to approach the movable side contact-separation portion 501 while maintaining the contact state between the suction side contact portion 400 and the movable side contact portion 500.

The contact biasing member 7 biases the attracting body 4 so that the engagement position of the attraction side engaging portion is located on the side closer to the movable body 5, and the engagement position is displaced away from the movable body 5 when the bimetal 6 is deformed.

As shown in FIG. 2, the operating mechanism 8 includes an operating unit 80 that can be operated from outside the case 2, and a switching structure 81 that switches the state of the circuit breaker 1 between an open state in which the contact unit 31 is open and a closed state in which the contact unit 31 is closed in response to operation of the operating unit 80.

The operating unit 80 has a base portion 800 that can rotate around a rotation axis 220 that extends along the width direction, and a lever portion 801 that extends from the base portion 800 to the outside of the case 2.

The switching structure 81 has a switching member 810 that switches the contact portion 31 between a closed state and an open state, i.e., that moves the movable side terminal 311 toward and away from the fixed side terminal 310, an opening biasing member 811 that biases the switching member 810, and an operating structure 812 for operating the switching member 810 by operating the operating portion 80.

The switching member 810 is slidable along the front-rear direction, and is configured to press the movable side terminal 311 against the fixed side terminal 310 as it slides rearward in the front-rear direction (direction from the front 20 toward the rear 21 of the case 2), and to release the pressing state against the movable side terminal 311 as it slides forward in the front-rear direction (direction from the rear 21 toward the front 20 of the case 2).

The opening biasing member 811 biases the switching member 810 toward the front side in the front-rear direction. The opening biasing member 811 may be configured to always apply a biasing force to the switching member 810, or may be configured to apply a biasing force to the switching member 810 when the switching member 810 slides from the front 20 side to the back 21 side of the case 2.

The actuation structure 812 has a link member 812a connected to the operating unit 80 and a push-in member 812b attached to the link member 812a.

The link member 812a has an operating unit side shaft portion 812aa that is inserted into the operating unit 80 along the width direction, and a pushing unit side shaft portion 812ab that is connected to the operating unit 80 side insertion portion and is inserted into the pushing member 812b along the width direction.

In addition, the link member 812a is configured to push the pushing member 812b rearward in the front-to-rear direction as the operating unit 80 rotates to one side, and to pull the pushing member 812b forward in the front-to-rear direction as the operating unit 80 rotates to the other side.

The pushing member 812b has a base portion 812ba through which the pushing portion side shaft portion 812ab is inserted, an insertion piece portion 812bb that extends from the base portion 812ba and can be inserted into the hook retaining portion 54, and a pushing piece portion 812bc that extends from the base portion 812ba to the opposite side to the insertion piece portion 812bb and can be used to push the switching member 810.

The base portion 812ba has the push-in portion side shaft portion 812ab inserted along the width direction, and can rotate around the push-in portion side shaft portion 812ab. Therefore, when the base portion 812ba rotates relative to the push-in portion side shaft portion 812ab, the insertion piece portion 812bb and the push-in piece portion 812bc also rotate in the same direction around the push-in portion side shaft portion 812ab.

When the insertion piece 812bb is inserted into the hook retaining portion 54 and the link member 812a is pulling up the base portion 812ba, it is hooked to the inner surface of the hook retaining portion 54 on the front-to-rear side in the front-to-rear direction, and when the insertion piece 812bb is inserted into the hook retaining portion 54 and the link member 812a is pushing the base portion 812ba, it is hooked to the inner surface of the hook retaining portion 54 on the rear side in the front-to-rear direction (see FIG. 10).

The configuration of the circuit breaker 1 according to this embodiment is as described above. Next, we will explain the operation of the circuit breaker 1.

When using the circuit breaker 1, the case 2 is attached to the distribution board, and then each contact portion 31 is closed. In this embodiment, as shown in FIG. 10, when the operating portion 80 is rotated, the link member 812a pushes the pushing member 812b toward the rear surface 21 of the case 2.

At this time, since the insertion piece 812bb is hooked to the hook retaining portion 54, the pushing piece 812bc moves rearward in the front-to-rear direction relative to the insertion piece 812bb.

The switching member 810 is then pushed rearward in the front-rear direction by the pushing portion 712a and moves, and the moving side terminal 311 is then pushed toward the fixed side terminal 310 by the switching member 810.

Then, when the movable terminal 311 and the fixed terminal 310 come into contact, the circuit 3 switches to a closed state.

The switching member 810 and the pushing member 812b are subjected to a biasing force (a biasing force toward the front in the front-rear direction) by the opening biasing member 811, but because the movement of the switching member 810 and the pushing member 812b toward the front in the front-rear direction is locked by the pushing of the link member 812a, the state in which the movable side terminal 311 and the fixed side terminal 310 are in contact (a state in which the circuit 3 is closed) is maintained. In other words, the movable body 5 switches to the holding state.

When the movable body 5 is switched to the holding state, the suction side contact portion 400 and the movable side contact portion 500 are in contact, while the suction side contact-separation portion 401 and the movable side contact-separation portion 501 are separated. In this way, the gap between the suction side opposing surface 40 (suction side first region 40a) and the movable side opposing surface 50 (movable side first region 50a) narrows toward the suction side contact portion 400 and the movable side contact portion 500 due to partial contact between the suction side contact portion 400 and the movable side contact portion 500. Therefore, the gap when the movable body 5 is in the holding state can be kept small while ensuring the movement of the movable body 5 toward the suction body 4.

The circuit breaker 1 according to this embodiment is configured to perform an operation in which the bimetal 6 bends to break the circuit 3 (time-delayed tripping), and an operation in which the movable body 5 is attracted to the attraction body 4 before the bimetal 6 bends to break the circuit 3 (instantaneous tripping). Note that in the normal state, the push operation part 53 is not pressed by the bimetal 6 (see FIG. 12).

When the circuit 3 is interrupted by time delay tripping, the bimetal 6 is first heated by the overcurrent flowing through the circuit 3. As a result, the bimetal 6 bends so that the other plate surface is recessed, and the movable end 61 pushes the pushing portion 53 toward the attracting body 4 (see Figures 11 and 13(a)). As a result, the movable body 5 rotates toward the attracting body 4 around its own rotation starting point.

When the movable body 5 rotates toward the attraction body 4, the movable side contact part 500 presses the attraction side contact part 400, causing the attraction body 4 to rotate around the rotation axis 220, and the attraction side contact part 401 moves toward the movable side contact part 501. Therefore, the attraction side contact part 401 and the movable side contact part 501 move in directions approaching each other.

When the insertion piece 812bb is released from the latch retainer 54, the locked state is released, and the biasing force of the release biasing member 811 pulls the switching member 810 and the pushing member 812b toward the front in the front-to-rear direction, and the movable terminal 311 moves away from the fixed terminal 310, thereby interrupting the circuit 3.

At this time, the movable body 5 and the suction body 4 are in contact with each other, but a gap is formed between the escape surface 220b of the rotating shaft and the inner circumferential surface that defines the through hole 410 in the side wall portion 41. Therefore, the suction body 4 is set with a movement margin toward the opposite side to the movable body 5 side in the vertical width direction.

Therefore, when the bimetal 6 is further deflected (deformed) while the movable body 5 and the attracting body 4 are in contact with each other, the movable body 5 and the attracting body 4 move within the gap in the direction in which the bimetal 6 is deflected (see FIG. 13(b)).

When the circuit 3 is interrupted by instantaneous tripping, the magnetic force generated in the attracting body 4 by the excessive current attracts the movable body 5 toward the attracting body 4. As a result, the insertion piece 812bb is released from the latching retaining portion 54, the movable side terminal 311 is separated from the fixed side terminal 310, and the circuit 3 is interrupted.

Even at this time, the movable body 5 and the suction body 4 are in contact with each other, but a gap is formed between the escape surface 220b of the pivot shaft 220 and the inner circumferential surface that defines the through hole 410 in the side wall portion 41. Therefore, the suction body 4 is set with a movement margin toward the opposite side to the movable body 5 side in the vertical width direction.

Therefore, when the bimetal 6 is further deflected (deformed) while the movable body 5 and the attracting body 4 are in contact with each other, the movable body 5 and the attracting body 4 move within the gap in the direction in which the bimetal 6 is deflected.

As described above, according to the circuit breaker 1 of this embodiment, even when the circuit 3 is interrupted and the movable body 5 and the suction body 4 are in contact, there is some room for movement of the movable body 5 and the suction body 4 in the amount of the gap between the case side engagement part and the suction side engagement part.

Therefore, when the bimetal 6 deforms while the movable body 5 is in contact with the attracting body 4, the engaging position of the attracting side engaging part relative to the case side engaging part is displaced from the side closer to the movable body 5 to the side farther from the movable body 5 due to the biasing force of the contact biasing member 7, so that the attracting body 4 and the movable body 5 move in the deformation direction of the bimetal 6.

As a result, the movement of the movable body 5 and the attraction body 4 is not locked until the engagement position of the attraction side engagement part is displaced from the side closer to the movable body 5 to the side farther from the movable body 5, and it is possible to prevent a portion of the bimetal 6 from bending significantly and causing plastic deformation.

The circuit breaker of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

In the mounting structure of the above embodiment, the case side engagement portion is the pivot shaft 220 and the suction side engagement portion is the through hole 410, but this configuration is not limited to this. For example, the mounting structure may be configured so that the suction side engagement portion is the pivot shaft and the case side engagement portion is a recess into which the pivot shaft can be inserted. In this way, the case side engagement portion and the suction side engagement portion of the mounting structure only need to be configured so that, when engaged with each other, their mutual engagement positions move (change) in the direction in which they approach and move away from the movable body 5 (the vertical width direction).

Although not specifically mentioned in the above embodiment, the movement of the suction body 4 may be in a direction along the vertical width direction, or in a direction inclined relative to the vertical width direction.

In other words, if the suction body 4 is designed to change its position in the vertical width direction, the movement of the suction body 4 may be set along the vertical width direction, or along a direction that is inclined toward the vertical width direction.

In the above embodiment, when the contact portion 31 is switched to the open state, the attractor 4 and the movable body 5 are in partial contact with each other, but this configuration is not limited thereto. For example, when the contact portion 31 is switched to the open state, the attractor 4 and the movable body 5 may be completely separated from each other.

In the above embodiment, the suction side facing surface 40 may be configured such that the suction side contact portion 401 is positioned farther from the movable body 5 than the suction side contact portion 400 by tilting the entire suction body 4, or the suction side facing surface 40 itself may be formed in an inclined shape.

In the above embodiment, the movable body 5 is configured to be rotatable by inserting the attachment parts 52 extending outward from both sides of the movable body main body part 51 in the width direction into the receiving part 221, but this configuration is not limited to this. For example, the movable body 5 may be configured to be rotatable by inserting a shaft protruding from the inner surface of the side surface 22.

In the above embodiment, the movable body main body 51 of the movable body 5 is plate-shaped, but is not limited to this configuration. For example, the movable body main body 51 of the movable body 5 may be column-shaped or frame-shaped.

In the above embodiment, the suction side facing surface 40 is inclined with respect to the front-rear direction, and the movable side facing surface 50 is arranged straight along the front-rear direction, but this configuration is not limited to this. For example, both the suction side facing surface 40 and the movable side facing surface 50 may be inclined with respect to the front-rear direction, or only the movable side facing surface 50 may be inclined with respect to the front-rear direction.

The circuit breaker of the above embodiment includes a case, a circuit connected to a terminal on the power supply side and a terminal on the load side, a contact portion for opening and closing the circuit, an attracting body which becomes an electromagnet when a current flows through the circuit, a movable body which is switchable between a holding state in which the contact portion is held in a closed state and which is disposed opposite the attracting body with a space therebetween for movement toward the attracting body, and a release state in which the contact portion is released from the holding state by moving toward the attracting body and coming into contact with the attracting body, thereby allowing the contact portion to be opened, a bimetal which deforms when heated so as to move the movable body toward the attracting body, and a bimetal which is connected to the case and which is switchable between a holding state in which the contact portion is held in a closed state and which is disposed opposite the attracting body with a space therebetween for movement toward the attracting body, and a release state in which the contact portion is released from the holding state by moving toward the attracting body and coming into contact with the attracting body, The circuit breaker includes an attachment structure that is attached to the case and a biasing member that biases the attraction body in a direction approaching the movable body, the attachment structure having a case side engagement part provided on the case and an attraction side engagement part provided on the attraction body and engaging with the case side engagement part, the attraction side engagement part is configured so that an engagement position of the attraction side engagement part moves relative to the case side engagement part in a direction approaching and moving away from the movable body, and the biasing member biases the attraction body so that the engagement position of the attraction side engagement part is located on the side closer to the movable body and is displaced away from the movable body when the bimetal is deformed.

In the circuit breaker of the above configuration, when the bimetal deforms while the movable body is in contact with the attracting body, the biasing force of the biasing member displaces the engagement position of the attraction side engagement part relative to the case side engagement part from the side closer to the movable body to the side farther from the movable body, so that the attraction body and the movable body move in the direction of deformation of the bimetal. Therefore, during the period until the engagement position of the attraction side engagement part displaces from the side closer to the movable body to the side farther from the movable body, it is possible to prevent partial obstruction of deformation of the bimetal, thereby preventing plastic deformation of a part of the bimetal.

The circuit breaker of the above embodiment includes a circuit connected to a terminal on the power supply side and a terminal on the load side, a contact portion for opening and closing the circuit, an attractor that becomes an electromagnet when a current flows through the circuit, and a movable body that can hold the contact portion in a closed state and can be switched between a holding state in which the attractor is disposed opposite the attractor with a gap therebetween that allows movement toward the attractor, and a release state in which the contact portion is released from the holding state when the attractor moves toward the attractor and comes into contact with the attractor, thereby allowing the contact portion to be opened. The attractor is configured to be movable in a direction opposite the movable body, and the position of the attractor in the opposing direction in the release state of the movable body is a position that is moved to the opposite side to the side where the movable body is disposed, relative to the position of the attractor in the holding state of the movable body.

1...circuit breaker, 2...case, 3...circuit, 4...attraction body, 5...movable body, 6...bimetal, 7...contact biasing member, 8...operation mechanism, 20...front, 21...back, 22...side, 30...input terminal, 31...contact portion, 40...attraction side facing surface, 41...side wall portion, 42...connected wall portion, 50...movable side facing surface, 51...movable body main body portion, 52...mounting portion, 53...push operation portion, 54...hook retaining portion, 61...movable end portion, 80...operation portion, 81...switching structure, 220...rotation shaft, 220a...guide surface, 220b...relief surface, 220ba...curved surface, 220b b...inclined surface, 221...receiving portion, 310...fixed side terminal, 311...movable side terminal, 400...suction side contact portion, 401...suction side contact portion, 410...through hole, 500...movable side contact portion, 501...movable side contact portion, 712a...push portion, 800...base portion, 801...lever portion, 810...switching member, 811...opening biasing member, 812...operation structure, 812a...link member, 812aa...operation portion side shaft portion, 812ab...push portion side shaft portion, 812b...push member, 812ba...base portion, 812bb...insertion piece portion, 812bc...push piece portion

Claims (1)

Case and
A circuit connected to a terminal on the power supply side and a terminal on the load side;
A contact portion for opening and closing the circuit;
an attracting body which becomes an electromagnet by a current flowing through the circuit;
a movable body that can hold the contact portion in a closed state and is switchable between a holding state in which the contact portion is disposed opposite the attraction body with a gap therebetween to allow for movement of the contact portion toward the attraction body, and a release state in which the contact portion is released from the holding state against the closed state and can be opened when the movable body moves toward the attraction body and comes into contact with the attraction body;
The attraction body is configured to be movable in a direction opposite to the movable body,
a position of the attraction body in the opposing direction in the released state of the movable body is a position where the attraction body moves to the opposite side to the side where the movable body is disposed, as a result of the attraction body rotating with respect to the case about an axis extending along a width direction perpendicular to the opposing direction and moving with respect to the case in the opposing direction, from a position of the attraction body in the held state of the movable body.
Circuit breaker.