JP2020155330A - Circuit breaker - Google Patents

Abstract

To provide a circuit breaker capable of restraining plastic-deformation of a bimetal.SOLUTION: A circuit breaker includes a contact part for opening and closing a circuitry, an attraction body becoming an electromagnet by the electric current of the circuitry, a movable body capable of switching to a holding state for holding closed state of the contact part and facing the attraction body with a space, and a release state for moving to the attraction body side and coming into contact with the attraction body, and making the contact part openable by releasing the holding to the closed state, a bimetal for moving the movable body to the attraction body side by deformation incident to rise of temperature, an attachment structure for attaching the attraction body into the case, and an energization member for energizing the attraction body to the movable body side. The attachment structure has a case side engagement part of engaging cases, and an attraction side engagement part of the attraction body, where the attraction side engagement part is energized to the movable body side by the energization member so that the engagement position with the case side engagement part displaces from the side close to the movable body to the side remote therefrom during deformation of the bimetal.SELECTED DRAWING: Figure 2

Description

The present invention relates to a circuit breaker for protecting a device or the like on the load side by interrupting the circuit when an overcurrent flows through the circuit connecting the power supply side and the load side.

The circuit breaker includes, for example, a circuit connected to a terminal on the power supply side and a terminal on the load side, and a movable contact provided on the circuit, as shown in FIGS. 7 to 9 of Patent Document 1. And the fixed contact, the opening / closing mechanism for switching the open / closed state of the movable contact and the fixed contact, the first iron core which is a magnetic material and becomes an electromagnet by the current flowing in the circuit, and the magnetic material and the first iron core. It is known that a second iron core is arranged so as to face each other with a space between them, and a strip-shaped bimetal arranged between the first iron core and the second iron core.

The opening / closing mechanism of the circuit breaker having the above configuration is capable of engaging with the first iron core, and by switching the engaging state with respect to the first iron core, an operating plate for switching the opening / closing state between the movable contact and the fixed contact is provided. It has a structure to have.

Further, in the circuit breaker having the above configuration, the operating plate is suspended from the first iron core when the movable contact and the fixed contact are closed, but when the bimetal generates heat due to the overcurrent flowing in the circuit, The bimetal bends toward the second core, and the first core moves toward the second core to release the engagement of the operating plate with respect to the first core. As a result, the movable contact and the fixed contact are opened (so-called time extension removal is performed).

Further, in the circuit breaker having the above configuration, when a magnetic force is generated in the first core due to an excessive current such as a short-circuit current flowing in the circuit, and the first core moves to the second core side before the bimetal bends. In this case as well, the actuating plate is released from the first iron core, and the movable contact and the fixed contact are opened (so-called instantaneous tripping is performed).

Japanese Unexamined Patent Publication No. 2002-25415

By the way, the second iron core of the circuit breaker having the above configuration is in a state of being urged toward the first iron core by a coil spring attached to the shaft portion inside the instrument, and rotates around the shaft portion. Although it is possible, the movement of the first core as well as the second core occurs when the movable contact and the fixed contact are opened, regardless of whether the time-extended trip is performed or the instantaneous trip is performed. As a result of being regulated, the movement of bimetal will also be regulated.

Therefore, in the circuit breaker having the above configuration, if the bimetal continues to bend while the movable contact and the fixed contact are opened and the movement of the respective iron cores is regulated, a part of the bimetal is generated by the force of the bimetal itself. In some cases, it bends greatly and causes plastic deformation.

Therefore, in view of such circumstances, it is an object of the present invention to provide a circuit breaker capable of suppressing plastic deformation of a bimetal.

The circuit breaker of the present invention
With the case
The circuit that connects the terminal on the power supply side and the terminal on the load side,
A contact part that opens and closes the circuit
An attractor that becomes an electromagnet due to the current flowing through the circuit,
A holding state in which the contact portion is held closed and the suction body is arranged so as to face the suction body with a space for movement toward the suction body, and a holding state in which the contact portion moves toward the suction body and comes into contact with the suction body. As a result, the movable body that can be switched to the released state in which the contact portion can be opened by releasing the holding of the contact portion in the closed state.
A bimetal that deforms to move the movable body toward the suction body when the temperature rises.
A mounting structure for mounting the suction body inside the case,
A urging member for urging the suction body in a direction approaching the movable body is provided.
The mounting structure has a case-side engaging portion provided on the case and a suction-side engaging portion provided on the suction body and engaged with the case-side engaging portion.
The suction side engaging portion is configured so that the engaging position moves with respect to the case side engaging portion in the direction of contacting and separating from the movable body.
In the urging member, the engaging position of the suction side engaging portion is located closer to the movable body, and the engaging position is displaced to the side farther from the movable body when the bimetal is deformed. Is urging the suction body,
Circuit breaker.

According to the circuit breaker having the above configuration, when the bimetal is deformed while the movable body is in contact with the suction body, the engagement position of the suction side engagement portion with respect to the case side engagement portion is changed by the urging force of the urging member. , Since the displacement is from the side close to the movable body to the side far from the movable body, the suction body and the movable body move in the deformation direction of the bimetal. Therefore, it is possible to prevent the deformation of the bimetal from being partially hindered until the engaging position of the suction side engaging portion is displaced from the side close to the movable body to the side far from the movable body. It is possible to prevent a part from being plastically deformed.

As described above, the circuit breaker of the present invention can exert an excellent effect of suppressing the 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 same embodiment. FIG. 3 is an enlarged view of the inside of the case of the circuit breaker according to the embodiment. FIG. 4 is an explanatory view of a mounting structure of a suction body of the circuit breaker according to the same embodiment. FIG. 5 is an explanatory view of a mounting structure of a movable body of the circuit breaker according to the same embodiment. FIG. 6 is a view of the suction body of the circuit breaker according to the same embodiment as viewed from the movable body side. FIG. 7 is a view of the suction body of the circuit breaker according to the same 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 same 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 operation explanatory view of the circuit breaker according to the same embodiment, and is an explanatory view of a state in which the contact portion is closed. FIG. 11 is an operation explanatory view of the circuit breaker according to the same embodiment, and is an explanatory view of a state in which the contact portion is open. FIG. 12 is an operation explanatory view of the circuit breaker according to the same embodiment, and is an explanatory view of a suction body and a movable body before breaking the circuit. 13A and 13B are explanatory views of a suction body and a movable body after the circuit is cut off, and FIG. 13B is an explanatory view of a state in which the suction body and the movable body move after the circuit is cut off.

Hereinafter, the circuit breaker according to the embodiment of the present invention will be described with reference to the accompanying drawings.

The circuit breaker is for protecting the equipment connected to the load side by interrupting the circuit when an abnormal current flows.

The circuit breaker 1 includes a case 2 as shown in FIG. 1, a circuit 3 that electrically connects the power supply side and the load side as shown in FIG. 2, and a current flowing through the circuit 3. A suction body 4 serving as an electromagnet and a holding state in which the contact portion 31 can be held in a closed state and are arranged so as to face the suction body 4 with a space for movement toward the suction body 4 side. The movable body 5 can be switched to a release state in which the contact portion 31 can be opened by releasing the holding of the contact portion 31 against the closed state by moving to the suction body 4 side and contacting the suction body 4. A bimetal 6 that deforms the movable body 5 so as to move toward the suction body 4 when the temperature rises, and an urging member that urges the suction body 4 toward the movable body 5 (hereinafter referred to as a contact urging member). (Referred to as) 7 and an operation mechanism 8 capable of opening and closing the contact portion 31.

In the case 2, as shown in FIG. 1, when the circuit breaker 1 is attached to the distribution board, the front surface 20 which is one surface arranged on the front side and the one surface opposite to the front surface 20 (used). It includes a back surface 21 (one surface that is sometimes arranged to face the mounting surface to the distribution board), and a pair of side surfaces 22 that are continuous with the front surface 20 and the back surface 21 and are arranged to face each other. The side surface 22 of the case 2 is a surface facing the side surface 22 of the case 2 of another circuit breaker 1 in a state where the circuit breaker 1 is installed on the distribution board.

In the present embodiment, the direction in which the front surface 20 and the back surface 21 of the case 2 are lined up is the front-rear direction, the direction in which the pair of side surfaces 22 are lined up is the width direction, and the direction orthogonal to each of the front-back direction and the width direction is the vertical width direction. The following explanation will be given in the name of.

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

In the following description, the state in which the contact portion 31 closes the electric circuit (circuit) is referred to as a closed state, and the state in which the contact portion 31 opens the electric circuit (circuit) is referred to as an open state. is there.

Each contact portion 31 has a fixed side terminal 310 fixed in the case 2 and a movable side terminal 311 that can be brought in and out of the fixed side terminal 310.

The movable side terminal 311 is made of an elongated metal plate that can be elastically deformed. One end (base end) side of the movable side terminal 311 in the longitudinal direction is positioned (fixed) in the case 2.

The other end (tip) side of the movable side terminal 311 in the longitudinal direction is spaced from the fixed side terminal 310 on the front side in the front-rear direction when the contact portion 31 is switched to the open state. Are arranged. Therefore, the movable side terminal 311 bends (elastically deforms) toward the fixed side terminal 310, so that the tip end portion of the movable side terminal 311 comes into contact with the fixed side terminal 310 (that is, it switches to the closed state). ) Is configured.

The attracting body 4 is configured to generate a magnetic force according to the magnitude of the current flowing through the circuit. The suction body 4 according to the present embodiment has a suction side facing surface 40 arranged toward the movable body 5. In the state where the movable body 5 is in the holding state, the suction side facing surface 40 is movable at a portion on one side (a portion arranged on the starting point (rotating shaft 220) side when the suction body 4 moves). A contact portion (hereinafter referred to as a suction side contact portion) 400 that contacts the body 5 (movable side facing surface of the movable body 5 described later) and a movable body 5 (movable side facing surface of the movable body 5 described later) at the other side portion. The surface) includes a contact / detachment portion (hereinafter, referred to as a suction side contact / detachment portion) 401.

As shown in FIG. 6, the suction body 4 according to the present embodiment is a series of a pair of side wall portions 41 arranged to face each other at intervals in the lateral width direction and a series connected to each of the pair of side wall portions 41. It has a wall portion 42.

The pair of side wall portions 41 are arranged so as to be parallel to each other with the wall surfaces facing in the lateral width direction. The suction side facing surface 40 is composed of a portion of the side wall portion 41 that is arranged toward the movable body 5 side.

The suction side facing surface 40 is a flat surface, and in a normal state (a state in which the operation of switching from the holding state to the holding release state is not taken), the suction side contact / detachment portion 401 is the suction side contact portion in the vertical width direction. It is tilted so as to be located farther from the movable body 5 than the 400.

Further, each of the pair of side wall portions 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 wall portions 41 is configured to be rotatable about an axis extending along the lateral width direction. In the present embodiment, a through hole 410 is formed in the side wall portion 41, and a rotation shaft 220 projecting from the inside of the side surface 22 of the case 2 toward the inside in the lateral width direction is inserted into the through hole 410. ing.

The through hole 410 is a round hole having a uniform or substantially uniform hole diameter over the entire circumference. The through hole 410 is formed at a position deviated from the suction side contact portion 400 to the other side, that is, a position deviated to the suction side contact / detachment portion 401 side. In the present embodiment, the through hole 410 is formed at a position shifted from the central portion in the front-rear direction to the suction side contact / separation portion 401 side.

Here, the rotation shaft 220 will be described. On the tip end side of the rotating shaft 220, at least the horizontal width in the vertical width direction is smaller than the hole diameter of the through hole 410.

On the tip end side of the rotation shaft 220 of the present embodiment, a guide surface 220a located on one side (opposite side to the movable body 5 side) in the vertical width direction and the other side (movable body 5) in the vertical width direction. The flank 220b located on the side) is included.

The guide surface 220a has an arc shape. Further, the curvature of the guide surface 220a is the same as or substantially the same as the curvature of the through hole 410.

The flank surface 220b is formed so as to be located inside (the center side of the rotation shaft 220) from the extension line of the guide surface 220a.

Further, as shown in FIG. 12, the flank surface 220b extends from both ends of the arcuate curved surface 220ba located at the frontmost position in the vertical width direction and the curved surface 220ba and is continuous with the guide surface 220a. A pair of inclined surfaces 220bb and a pair of inclined surfaces 220bb are included, and the pair of inclined surfaces 220bb are inclined toward the outside in the front-rear direction from the curved surface 220ba side to the guide surface 220a side.

Therefore, the rotating shaft 220 has a gap between the flank surface 220b and the inner peripheral surface when the guide surface 220a is in contact with the inner peripheral surface defining the through hole 410 in the side wall portion 41. Is configured to allow

Therefore, the suction body 4 can rotate with the through hole 410 as the rotation starting point (center), and can also move in the lateral width direction by the amount of the gap. When the entire suction body 4 rotates about the rotation shaft 220, the suction side contact portion 400 and the suction side contact / detachment portion 401 are centered on the rotation shaft 220 inserted through the through hole 410. It is designed to rotate along the circumferential direction.

Therefore, in the circuit breaker 1 according to the present embodiment, the case-side engaging portion formed of the rotating shaft 220 of the case 2 and the through hole 410 of the suction body 4 are formed and engaged with the case-side engaging portion. A mounting structure for mounting the suction body 4 to the case 2 is configured by the suction side engaging portion, and further, the suction side engaging portion is engaged with the case side engaging portion in the direction of contacting and separating from the movable body 5. It is configured so that the engaging position of the portion changes.

As shown in FIG. 7, the continuous wall portions 42 are connected to each other at the ends of each side wall portion 41 on the side opposite to the movable body 5 side, and are arranged toward the movable body 5 side. Both the inner surface (hereinafter referred to as the inner surface) and the surface (hereinafter referred to as the outer surface) arranged toward the side opposite to the movable body 5 side are flat.

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

The movable side facing surface 50 has a contact portion (hereinafter, referred to as a movable side contact portion) 500 that contacts the suction side contact portion 400 in a state where its own state is switched to the holding state, and the suction side contact / separation. A contact / detachment portion (hereinafter, referred to as a movable side contact / detachment portion) 501, which is arranged with a gap that allows contact / detachment with respect to the portion 401, is included.

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

The movable body 5 according to the present embodiment includes an elongated plate-shaped movable body main body 51, a mounting portion 52 to which the movable body main body 51 is rotatably attached to the case 2, and a suction body 4 by a bimetal 6. It has a push operation unit 53 that is pushed toward the side.

One plate surface of the movable body main body 51 is arranged toward the suction body 4 side, and the other plate surface is arranged toward the side opposite to the suction body 4 side, and the movable body main body 51 is movable by the one plate surface. The side facing surface 50 is configured.

Further, in the normal state, the movable body main body 51 is arranged so as to be in a posture extending straight along the front-rear direction, and is movable by the region on the back surface 21 side of the case 2 on one plate surface. The side contact portion 500 is configured, and the movable side contact / detachment portion 501 is configured by the region on the front surface 20 side of the case 2 in one plate surface of the movable body main body portion 51.

Further, the movable body main body 51 is formed with a hook holding portion 54 used for holding the closed state of the contact portion 31. The hook holding portion 54 is a hole formed through one plate surface and the other plate surface of the movable body main body 51, and is composed of, for example, a recess that opens only on the other plate surface side. You may be.

As shown in FIG. 5, the mounting portions 52 are continuously provided at the ends of the movable body main body 51 arranged on the back surface 21 side of the case 2, and are connected from both sides of the movable body main body 51 in the lateral width direction. It extends outward. Further, the mounting portion 52 is rotatably inserted into the concave receiving portion 221 formed inside the side surface 22.

Further, the mounting portion 52 is arranged at a position shifted to the back surface 21 side of the case 2 with reference to 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 arranged at a position shifted in the front-rear direction (a position shifted to the back surface 21 side of the case 2) with respect to the rotation starting point of the suction body 4. As a result, the movable body 5 can rotate with the attachment portion 52 as the rotation starting point so that the movable side contact / detachment portion 501 is brought into contact with and separated from the suction side contact / detachment 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 with the heating. In the present embodiment, the overcurrent is a current that heats the bimetal 6 so as to move the movable body 5 toward the suction body 4 due to deformation (so-called current that flows when the time-extended trip is performed). The excessive current is a current that generates a magnetic force having a strength that attracts the movable body 5 to the attracting body 4 (so-called current that flows when performing instantaneous tripping).

The bimetal 6 has a strip-like shape, and the coefficient of thermal expansion on one plate surface side is higher than the coefficient of thermal expansion on the other plate surface side.

The bimetal 6 is arranged between the suction body 4 and the movable body 5. More specifically, the bimetal 6 is arranged between the pair of side wall portions 41 of the suction body 4, one of the plate surfaces faces the movable body 5, and the other plate surface is continuously provided. The posture is such that it faces the wall portion 42 side.

Only one end (hereinafter, referred to as a fixed end) 60 of both ends of the bimetal 6 in the longitudinal direction is fixed in the case 2.

The other end (hereinafter, referred to as a movable end) 61 of both ends of the bimetal 6 in the longitudinal direction is arranged to face the pushing operation portion 53 of the movable body 5 in the vertical width direction. Further, the movable end portion 61 of the bimetal 6 is arranged with the other plate surface side facing the pushing operation portion 53 (see FIG. 9).

Therefore, when the bimetal 6 is heated by the overcurrent flowing through the circuit 3, the other plate surface bends in a concave shape, and the movable end portion 61 pushes the pushing operation portion 53 toward the suction body 4 side accordingly. It is configured to be pushed toward.

The contact urging member 7 is fixed in the case 2 in a positioned state, and is configured to urge the continuous wall portion 42 of the suction body 4 toward the movable body 5.

Further, as shown in FIG. 3, the contact urging member 7 is located at a position deviated from the rotation starting point of the suction body 4 to the rotation starting point side of the movable body 5 in the front-rear direction (in the present embodiment, the suction body). (Between the rotation starting point of 4 and the rotation starting point of the movable body 5), the suction body 4 is configured to be urged toward the movable body 5.

As a result, in the normal state, the suction body 4 is in an inclined posture so that the suction side contact portion 400 approaches the suction side contact / detachment portion 401, and the suction side contact portion 400 is in a movable side contact portion 500. When pushed to, the suction side contact / detachment portion 401 rotates so as to approach the movable side contact / detachment portion 501 while maintaining the contact state between the suction side contact portion 400 and the movable side contact portion 500.

Further, in the contact urging member 7, the engaging position of the suction side engaging portion is located closer to the movable body 5, and the engaging position is far from the movable body 5 when the bimetal 6 is deformed. The suction body 4 is urged so as to be displaced to.

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

The operation unit 80 has a base unit 800 that can rotate about a rotation shaft 220 that extends along the lateral width direction, and a lever unit 801 that extends from the base unit 800 to the outside of the case 2.

The switching structure 81 switches the contact portion 31 between the closed state and the open state, that is, the switching member 810 that brings the movable side terminal 311 into contact with and the fixed side terminal 310, and the opening urging that urges the switching member 810. It has a member 811 and an operating structure 812 for operating the switching member 810 by operating the operating unit 80.

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

The opening urging member 811 urges the switching member 810 toward the front side in the front-rear direction. The opening urging member 811 may be configured to always apply an urging force to the switching member 810, or is switched when the switching member 810 slides from the front 20 side to the back 21 side of the case 2. The member 810 may be configured to give an urging force.

The operating structure 812 has a link member 812a connected to the operation unit 80 and a pushing member 812b attached to the link member 812a.

The link member 812a is connected to the operation unit side shaft portion 812aa that is inserted into the operation unit 80 along the lateral width direction and the insertion portion that is connected to the operation unit 80 side insertion portion and is inserted into the push member 812b along the lateral width direction. It has a portion side shaft portion 812ab.

Further, the link member 812a pushes the pushing member 812b to the rear side in the front-rear direction as the operation unit 80 rotates to one side, and pushes the pushing member 812b as the operating unit 80 rotates to the other side. It is configured to be pulled toward the front side in the front-rear direction.

The pushing member 812b includes a base portion 812ba into which the pushing portion side shaft portion 812ab is inserted, an insertion piece portion 812bb extending from the base portion 812ba and capable of being inserted into the hook holding portion 54, and the base portion. It has a pushing piece portion 812bc that extends from 812ba to the side opposite to the insertion piece portion 812bb and is capable of pushing the switching member 810.

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

When the insertion piece portion 812bb is inserted into the hook holding portion 54 and the link member 812a is pulling up the base portion 812ba, the insertion piece portion 812bb is on the front side in the front-rear direction with respect to the inner surface of the hook holding portion 54. In a state where the hook is stopped, inserted into the hook holding portion 54, and the link member 812a pushes the base portion 812ba, the hook is stopped on the rear side in the front-rear direction with respect to the inner surface of the hook holding portion 54. (See FIG. 10).

The configuration of the circuit breaker 1 according to the present embodiment is as described above. Subsequently, the operation of the circuit breaker 1 will be described.

When the circuit breaker 1 is used, each contact portion 31 is closed after the case 2 is attached to the distribution board. In this embodiment, as shown in FIG. 10, when the operation unit 80 is rotated, the link member 812a pushes the pushing member 812b toward the back surface 21 side of the case 2.

At this time, since the insertion piece portion 812bb is hooked on the hook holding portion 54, the push piece portion 812bc moves to the rear side in the front-rear direction with respect to the insertion piece portion 812bb.

Further, the switching member 810 is pushed to the rear side in the front-rear direction by the pushing portion 712a to move, and further, the movable side terminal 311 is pushed toward the fixed side terminal 310 by the switching member 810.

Then, when the movable side terminal 311 and the fixed side terminal 310 come into contact with each other, the circuit 3 is switched to the closed state.

The switching member 810 and the pushing member 812b are subjected to the urging force by the opening urging member 811 (the urging force toward the front side in the front-rear direction), but the switching member 810 and the pushing member 812b are said to be pushed by the link member 812a. Since the movement toward the front side in the front-rear direction is locked, the state in which the movable side terminal 311 and the fixed side terminal 310 are in contact with each other (the state in which the circuit 3 is closed) is maintained. That is, the movable body 5 switches to the holding state.

In the state where 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 with each other, while the suction side contact / separation portion 401 and the movable side contact / separation portion 501 are separated from each other. There is. As described above, the gap between the suction side facing surface 40 (suction side first region 40a) and the movable side facing surface 50 (movable side first region 50a) is formed between the suction side contact portion 400 and the movable side contact portion 500. Is partially contacted, so that it becomes narrower toward the suction side contact portion 400 and the movable side contact portion 500 side. Therefore, it is possible to keep the gap small when the movable body 5 is in the holding state while ensuring the movement allowance of the movable body 5 toward the suction body 4.

In the circuit breaker 1 according to the present embodiment, the circuit 3 is interrupted by the bending of the bimetal 6 (time-extended tripping), and the movable body 5 is moved to the suction body 4 side before the bimetal 6 is bent. It is configured to perform an operation (instantaneous disconnection) in which the circuit 3 is interrupted by being attracted. In the normal state, the push operation unit 53 is not pressed by the bimetal 6 (see FIG. 12).

When the circuit 3 is cut off by the time-extended trip, the bimetal 6 is first heated by the overcurrent flowing through the circuit 3. Along with this, the bimetal 6 bends so that the other plate surface is recessed, and the movable end portion 61 pushes the pushing operation portion 53 toward the suction body 4 side (see FIGS. 11 and 13A). As a result, the movable body 5 rotates toward the suction body 4 side around its own rotation starting point.

When the movable body 5 rotates toward the suction body 4, the movable side contact portion 500 pushes the suction side contact portion 400, so that the suction body 4 rotates around the rotation shaft 220, and the suction side contact / detachment portion 401. Moves toward the movable side contact / detachment portion 501. Therefore, the suction side contact / separation portion 401 and the movable side contact / separation portion 501 move in a direction approaching each other.

Then, when the insertion piece portion 812bb is released from the hook holding portion 54, the locked state is released, so that the switching member 810 and the pushing member 812b are moved to the front side in the front-rear direction by the urging force of the opening urging member 811. The movable terminal 311 is separated from the fixed terminal 310, and the circuit 3 is cut off.

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 peripheral surface defining the through hole 410 in the side wall portion 41. Has been done. Therefore, the suction body 4 is set with a movement allowance to the side opposite to the movable body 5 side in the vertical width direction.

Therefore, when the bimetal 6 is further bent (deformed) while the movable body 5 and the suction body 4 are in contact with each other, the movable body 5 and the suction body 4 are bent in the direction in which the bimetal 6 is bent within the range of the gap. Move (see FIG. 13B).

When the circuit 3 is cut off by instantaneous disconnection, the movable body 5 is attracted to the suction body 4 side by the magnetic force generated in the suction body 4 due to the excessive current. Along with this, the insertion piece portion 812bb is detached from the hook holding portion 54, the movable side terminal 311 is separated from the fixed side terminal 310, and the circuit 3 is cut off.

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

Therefore, when the bimetal 6 is further bent (deformed) while the movable body 5 and the suction body 4 are in contact with each other, the movable body 5 and the suction body 4 are bent in the direction in which the bimetal 6 is bent within the range of the gap. Moving.

As described above, according to the circuit breaker 1 according to the present embodiment, even when the circuit 3 is interrupted and the movable body 5 and the suction body 4 are in contact with each other, the case side engaging portion and the suction body 4 are sucked. A movement allowance is created in the movable body 5 and the suction body 4 by the amount of the gap between the side engaging portion.

Therefore, if the bimetal 6 is deformed while the movable body 5 is in contact with the suction body 4, the engagement position of the suction side engagement portion with respect to the case side engagement portion is movable by the urging force of the contact urging member 7. Since the suction body 4 and the movable body 5 are displaced from the side closer to the body 5 to the side farther from the movable body 5, the suction body 4 and the movable body 5 move in the deformation direction of the bimetal 6.

Therefore, the movements of the movable body 5 and the suction body 4 are not locked until the engaging position of the suction side engaging portion is displaced from the side close to the movable body 5 to the side far from the movable body 5, and the bimetal 6 is used. It is possible to prevent a part from being greatly bent and causing plastic deformation.

It should be noted that the circuit breaker of the present invention is not limited to the above embodiment, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

In the mounting structure of the above embodiment, the case-side engaging portion is the rotating shaft 220 and the suction-side engaging portion is the through hole 410, but the present invention is not limited to this configuration. For example, the mounting structure may be configured such that the suction side engaging portion is a rotating shaft and the case side engaging portion is a recess into which the rotating shaft can be inserted. In this way, the case-side engaging portion and the suction-side engaging portion of the mounting structure move in a state of being engaged with each other in a direction of contacting and separating from the movable body 5 (the vertical width direction). It suffices if it is configured to (change).

Although not particularly mentioned in the above embodiment, the movement allowance of the suction body 4 may be a movement allowance in a direction along the vertical width direction, or a direction in which the suction body 4 is inclined with respect to the vertical width direction. May be good.

That is, as long as the position of the suction body 4 changes in the vertical width direction, the movement allowance of the suction body 4 may be set along the vertical width direction, or in the vertical width direction. It may be set along the direction of inclination.

In the above embodiment, in the state where the contact portion 31 is switched to the open state, the suction body 4 and the movable body 5 are partially in contact with each other, but the present invention is not limited to this configuration. For example, the suction body 4 and the movable body 5 may be completely separated from each other in a state where the contact portion 31 is switched to the open state.

In the above embodiment, as for the suction side facing surface 40, the suction side contact / detachment portion 401 may be arranged at a position farther from the movable body 5 than the suction side contact portion 400 by tilting the entire suction body 4. The side facing surface 40 itself may have an inclined shape.

In the above embodiment, the movable body 5 can be rotated by inserting the mounting portions 52 extending outward from both sides of the movable body main body 51 in the lateral width direction into the receiving portion 221. It was configured, but is not limited to this configuration. For example, the movable body 5 may be configured to be rotatable by having a structure in which a shaft projecting from the inner surface of the side surface 22 is inserted.

In the above embodiment, the movable body main body 51 of the movable body 5 has a plate shape, but the present invention is not limited to this configuration. For example, the movable body main body 51 of the movable body 5 may have a columnar shape or a frame shape.

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 the present invention is not limited to this configuration. For example, both the suction side facing surface 40 and the movable side facing surface 50 may be tilted with respect to the front-rear direction, or only the movable side facing surface 50 may be tilted with respect to the front-rear direction.

1 ... circuit breaker, 2 ... case, 3 ... circuit, 4 ... suction body, 5 ... movable body, 6 ... bimetal, 7 ... contact urging member, 8 ... operation mechanism, 20 ... front, 21 ... back, 22 ... Side surface, 30 ... Input terminal, 31 ... Contact part, 40 ... Suction side facing surface, 41 ... Side wall part, 42 ... Continuous wall part, 50 ... Movable side facing surface, 51 ... Movable body body part, 52 ... Mounting part , 53 ... Pushing operation part, 54 ... Hook holding part, 61 ... Movable end part, 80 ... Operating part, 81 ... Switching structure, 220 ... Rotating shaft, 220a ... Guide surface, 220b ... Escape surface, 220ba ... Curved surface , 220bb ... Inclined surface, 221 ... Receiving part, 310 ... Fixed side terminal, 311 ... Movable side terminal, 400 ... Suction side contact part, 401 ... Suction side contact / separation part, 410 ... Through hole, 500 ... Movable side contact part, 501 ... Movable side contact / detachment part, 712a ... Pushing part, 800 ... Base part, 801 ... Lever part, 810 ... Switching member, 811 ... Opening urging member, 812 ... Acting structure, 812a ... Link member, 812aa ... Operation part Side shaft part, 812ab ... Pushing part Side shaft part, 812b ... Pushing member, 812ba ... Base part, 812bb ... Inserting piece part, 812bc ... Pushing piece part

Claims (1)

With the case
The circuit that connects the terminal on the power supply side and the terminal on the load side,
A contact part that opens and closes the circuit
An attractor that becomes an electromagnet due to the current flowing through the circuit,
A holding state in which the contact portion is held closed and the suction body is arranged so as to face the suction body with a space for movement toward the suction body, and a holding state in which the contact portion moves toward the suction body and comes into contact with the suction body. As a result, the movable body that can be switched to the released state in which the contact portion can be opened by releasing the holding of the contact portion in the closed state.
A bimetal that deforms to move the movable body toward the suction body when the temperature rises.
A mounting structure for mounting the suction body inside the case,
A urging member for urging the suction body in a direction approaching the movable body is provided.
The mounting structure has a case-side engaging portion provided on the case and a suction-side engaging portion provided on the suction body and engaged with the case-side engaging portion.
The suction side engaging portion is configured so that the engaging position moves with respect to the case side engaging portion in the direction of contacting and separating from the movable body.
In the urging member, the engaging position of the suction side engaging portion is located closer to the movable body, and the engaging position is displaced to the side farther from the movable body when the bimetal is deformed. Is urging the suction body,
Circuit breaker.