JP2009259609A - Switching mechanism for circuit breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a switching mechanism for circuit breaker greatly improved in assembling workability, using a switching mechanism in a prior art to advantage as much as possible, and improved in the yield rate. <P>SOLUTION: The switching mechanism includes an operating member 101 protruded in one part thereof outside a circuit breaker and a switching mechanism 100 to be operated, being linked with the operating member, by operating the operating member to forcibly bring a fixed contact point and a movable contact point in contact with each other and to separate them from each other. The switching mechanism is characterized by providing a turning member 102 integrally formed with the operating member and turnably arranged in a unit body, a latch member 104 connected to the turning member by a link 103 so as to be operated with the turning operation of the turning member through the link, an operating plate 105 engaged with one part of the latch member, and a cross bar 106 always biased by an elastic member 108 in a direction, in which the movable contact point is separated from the fixed contact point, and a nearly U-shape support 107 for supporting the described members structuring the switching mechanism. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a circuit breaker, and more particularly to a switching mechanism for a circuit breaker used for a low piezoelectric path.

A structural example of a conventional circuit breaker is shown in FIGS. 6, 10 and 21 are terminal plates, 11 and 12 are contacts, 13 is a movable contact plate, 14 is an engagement piece, 15 is a bimetal, 16 is a press plate, 17 is a link, 18 is a handle, 19 is a crossbar, Reference numeral 20 denotes a lead wire, which has an elastic movable contact plate 13 that constantly biases the movable contact 12 by its own force or other force, an engagement piece 14, a presser plate 16, a link 17, a handle 18, and not shown. An open / close mechanism composed of a frame or the like presses against the opening biasing force in the contact closing direction to close or close the contact, or releases the pressing force to release the contact force by the movable contact plate itself or by other force. It has a structure that separates the contacts.

Reference numeral 19 denotes a crossbar, which links the above-mentioned mechanism and the movable contact plate. In particular, the open and closed states of a single mechanism are simultaneously and electrically insulated by two independent movable contact plates. For the purpose of transmission, it is mounted in a sliding guide groove formed on the base that slides only in the vertical direction of FIG. 6 and prevents movement in the other directions.

More specifically, when the mechanism is working in the direction of closing the contacts, the crossbar abutting portion 1602 of the presser plate 16 presses the upper center of the crossbar 19 and the crossbar 19 has two movable contacts. The contact is moved by moving in the direction in which both the plates 13 and 13 are pressed evenly.

On the other hand, when the mechanism is working in the direction of releasing the contact, the pressing restraint at the center upper part of the crossbar 19 of the crossbar abutting portion 1602 of the presser plate 16 is released, and the movable contact plate 13, The contact force is released by lifting both the crossbar 19 and the crossbar contact portion 1602 by the opening force of 13.

There are two cases where the above-mentioned contacts are separated. One is an operation from on to off by a manual handle, and the other is trip-off due to an abnormal current from the normal on time.

In the case of trip-off, the current to be interrupted is a considerably large current such as an overcurrent or a short-circuit current. is there. Therefore, as shown in FIG. 5, the cross bar 19 extends from between the two movable contact plates 13 and 13 to the back side 1302 of the cross bar main body 1902 mounting surface 1301 of the movable contact plate and spreads outward. If one of the contacts is slightly welded and difficult to separate, the opening force of the other contact works on the welded contact side via the crossbar with the engaging claws. Consideration is made so that welding does not occur.
Japanese Patent Laid-Open No. 6-236729 FIG. 4 and FIG.

However, in the circuit breaker having such a structure, in particular, the crossbar constituting the main part of the circuit breaker linked to the switching mechanism is not held by the frame holding the link or the like but is provided on the base. The structure is mounted in the sliding guide groove, and the movable contact plate, crossbar, and switching mechanism are all separated. Therefore, the assembly performance when manufacturing circuit breakers is not excellent, resulting in a decrease in production yield. There was a problem of being connected.

For example, when assembling the circuit breaker, the movable contact plate is placed on the base while the movable contact plate is hooked on the engaging claw 1901 provided on the cross bar 19 and the cross bar 19 is slid. The frame, which is arranged on the guide portion and holds the link or the like in that state, is arranged at a predetermined position of the base, and is assembled so that the movable contact plate and the frame are screwed to the base.

In this case, since the movable contact plate is only inserted into the engaging claw that is open on one side of the crossbar, the movable contact plate is not attached when the movable contact plate is attached to the base. It is easy to come off from the crossbar, and it is necessary to place the movable contact plate, the crossbar, and the frame holding the link etc. on the base at the same time. It was not excellent and the work required skill.

In addition, the movable contact plate urges the crossbar in the opening direction at all times due to its elasticity, so that it exerts an urging force in the direction to remove the crossbar and frame from the base, making assembly workability difficult. Met.

Therefore, the present invention has been made in view of such problems, and the assembly work is performed while making the most of the open / close mechanism of the conventional circuit breaker as much as possible without impairing the effect of preventing contact welding by the engaging claws. It is an object of the present invention to provide a circuit breaker switching mechanism that can greatly improve the performance and improve the yield during production.

In order to achieve the above object, according to the first aspect of the present invention, in a circuit breaker interposed in an electric circuit and for supplying, energizing and interrupting a current, a container comprising a case and a cover constituting the outer periphery of the circuit breaker An operating member partially protruding outside the container, and an opening / closing mechanism that operates in conjunction with the operating member by operating the operating member and forcibly contacts and separates the fixed contact and the movable contact. A rotating member disposed in the container so as to be rotatable between an ON state and an OFF state of the circuit breaker by operating the operating member, and constituting the opening / closing mechanism; A latch member that is connected to the member by a link and that operates in conjunction with the turning operation of the turning member via the link; an operating plate that engages a part of the latch member; and supports the movable contact. The movable contact is always fixed from the fixed contact by the elastic member. And a cross bar that is biased in a direction to release is obtained by providing a switching mechanism of the circuit breaker is characterized by comprising by supporting the shape of the support of substantially U.

According to such a configuration, the rotating contact member, the latch member, the operation plate, the crossbar, and the like that constitute the opening / closing mechanism are supported by the support member, so that the movable contact plate is supported by the support member during assembly. Provided is a circuit breaker switching mechanism that can be placed on the base in a state of being hooked on the engaging claws of the crossbar supported by the base, reducing the complexity of assembly work and improving the yield. be able to.

The point of action of the latch portion on the crossbar, the point of action of the elastic body on the crossbar, and the support portion of the elastic body by the support are arranged on substantially the same straight line, and the movable contact is separated. In a state, the cross bar may be configured to be held in a state of being pressed against the support by the elastic body.

According to such a configuration, the crossbar can be driven by transmitting the pressing force of the latch portion and the elastic force of the elastic body most efficiently at the time of contact and separation of the contacts, and unexpectedly in the assembled state of the support body. Even when an external force is applied, the assembled parts can be prevented from coming off or coming apart.

In addition, a winding spring is used as the elastic body, and an engagement portion that engages with the inside of the winding spring is provided on the support body, and the crossbar of the crossbar pressed by the winding spring operates. May be formed by providing a locking portion that restricts the movement in the vertical direction.

According to such a configuration, both the ease of attaching the elastic body and the difficulty of detaching the crossbar pressed by the elastic body from the support body can be improved at the same time, thereby further improving the assembly workability. Can improve the production yield.

The circuit breaker may be a two-pole circuit breaker.

According to such a configuration, the assembly workability of the two-pole circuit breaker, which has been complicated in the conventional assembly, can be greatly improved, and the production yield can be improved.

According to the present invention, the assembly workability can be improved while making the most of the open / close mechanism of the conventional circuit breaker as much as possible without impairing the effect of preventing contact welding by the engaging claws provided in the cross bar provided in the circuit breaker. It is possible to provide a circuit breaker switching mechanism that can be significantly improved and that can improve the yield during production.

Hereinafter, a circuit breaker according to a first embodiment of the present invention will be described in detail with reference to the drawings.

1 and 2 are perspective views showing an opening / closing mechanism portion of a circuit breaker according to the present invention. The opening / closing mechanism 100 is configured to turn on, energize, and interrupt a current in an electric circuit including a circuit breaker by driving the opening / closing mechanism.

The opening / closing mechanism 100 is unitized by using a support body 107 formed in a substantially U-shape that supports each component constituting the opening / closing mechanism at a predetermined position.

The parts constituting the opening / closing mechanism 100 are formed integrally with the operation member 101 and a part of the operation member 101 that protrudes outside the body constituting the outline of the circuit breaker, and operate the operation member 101. As a result, the rotating member 102 is rotatably arranged between the ON state (current input and energization) and the OFF state (current interruption) of the circuit breaker, and the rotating member 102 is connected to the link 103. A latch member 104 that operates in conjunction with the pivoting operation of the pivoting member 102 via the link 103, and an operating plate 105 provided with an engaging portion with which a part of the latch member 104 is engaged. In the completed state, the movable contact is supported, and a cross bar 106 urged by an elastic member 108 in a direction in which the movable contact is separated from the fixed contact is provided.

The operation member 101, the link 103, the latch member 104, and the operating plate 105 are pivotally supported by holes a provided at predetermined positions of the support body 107 with axes a to d, and are supported rotatably. Has been.

Further, the support 107 is provided with a guide hole having a meandering shape so as to restrict the movement trajectory of the link 103 and the latch member 104. When the operation member 101 is operated, the movement of the link 103 and the latch member 104 along the guide hole is restricted by a shaft c provided so as to penetrate each other. For example, the operation member 101 is connected to the circuit breaker. When operated in the ON direction, the rotating member rotates counterclockwise in the figure, and the latch member 104 operates to push down the cross bar 106.

At this time, the point of application of the latch member 104 to the cross bar 106, the point of action of the elastic body 108 to the cross bar, and the support portion of the elastic body 108 by the support 107 are arranged on substantially the same straight line. When the cross bar 106 is pushed down by the latch member 104 and the cross bar 106 is pushed up by the elastic body 108, the direction of the push down and the component force in the push up direction are minimized. The force in the push-down direction and the force in the push-up direction by the elastic body 108 are efficiently transmitted and driven.

As the elastic body 108, a winding spring is used, and the support 107 is provided with an engaging portion 1071 that engages with the inside of the winding spring, and the crossbar 106 pressed against the winding spring. A locking portion 1072 is provided to restrict movement in a direction perpendicular to the direction in which the cross bar 106 operates.

The operation plate 105 is pivotally supported by a shaft d in the figure, and is always urged in a direction (left direction in the figure) in which engagement with the latch member 104 is performed by a winding spring provided in the shaft portion. ing. When the tripping operation is performed by a tripping device (for example, an electromagnetic tripping device or a trip coil) provided in the circuit breaker in the on state, The engagement with the end of the latch portion 104 is released, the contact is released, and the state shifts to the off state. At this time, the shaft c in the figure connecting the latch member 104 and the link 103 is restricted in movement along the meandering guide hole provided in the support body 107, and when moving from the on state to the off state, While moving in the middle-up direction, it moves so as to slide in a direction (left direction in the figure) in which the engagement portion between the operating plate 105 and the latch member 104 is reduced. This is because, as will be described later, the engagement with the operation plate 105 is more reliably performed when the state is shifted to the OFF state. Note that the shape of the guide hole is not limited to a meandering shape, and may be appropriately determined according to the movement of the link shaft, such as an arc shape. For example, it may be configured as a gentle zigzag shape.

When an abnormal current is generated in the electric circuit and the circuit breaker itself interrupts the current, when the circuit breaker shifts from the on state to the off state, the latch member 104 and the operation plate 105 are temporarily engaged. However, in the off state, it is necessary to engage (reset) again in preparation for the transition to the on state. As described above, since the operating plate 105 is always urged in the direction in which the engagement is made by the winding spring, the latch member 104 needs to be reset against the urging force of the operating plate 105. In order to make the reset more reliable, the engagement portion between the operating plate 105 and the latch member 104 is reduced while moving upward in the figure during the transition to the OFF state (see FIG. The shape of the guide hole 1073 of the support is provided so as to slide in the middle left direction), and is configured so as not to receive the urging force by the winding spring of the operating plate 10 as much as possible.

Next, the assembly of the circuit breaker will be described with reference to FIGS. 3 and 4 show, as circuit breakers, examples of components such as a two-pole earth leakage breaker switching mechanism and tripping device used in single-phase two-wire and single-phase three-wire electric circuits. The exploded perspective view is shown.

Reference numeral 10 denotes a case of a part of the body constituting the outline of the circuit breaker. The case 10 has a load-side electric circuit configured to include a terminal 203 attached with a contact constituting an electric circuit, which will be described later, an opening / closing mechanism 100, and a thermal element 202 that acts on the opening / closing mechanism 100 to detach the opening / closing mechanism. Various parts constituting the circuit breaker are attached.

The load-side electric circuit includes a movable contact plate 201 that is elastically provided with a movable contact attached thereto, a bimetal 202 that is a thermal element electrically connected to the movable contact plate 201, and an electric power to the bimetal 202. The lead wire 2021 that constitutes the load side conductor connected to the lead wire 202, and the load side terminal 204 that is electrically connected to the lead wire 2021.

Further, since this circuit breaker is a leakage breaker, the lead wire is passed through a zero-phase current transformer (ZCT) 205 that detects a leakage current. Further, the output signal from the ZCT 205 is processed to determine whether or not a leakage current having a predetermined magnitude has occurred in the electric circuit. When a leakage current having a predetermined magnitude has occurred, a trip means described later is provided. A detection circuit 207 for applying a voltage to the trip coil 206 and driving the trip coil is provided.

These load side electric circuit and detection circuit are previously unitized.

First, the power supply side terminal 203 provided with the fixed contact is disposed on the case 10. Subsequently, a trip coil 206 that is driven by the detection circuit 207 and acts on the above-described operation plate to detach the opening / closing mechanism when a leakage occurs is disposed.

Subsequently, the movable contact plate 201 provided with the movable contact is inserted into the engaging claw 1061 provided on the cross bar of the unitized opening / closing mechanism so as to be sandwiched from both sides of the opening / closing mechanism, and the bimetal 202 is moved to the operation plate. Assembled so as to be closer to the power supply side than 105, and arranged in the case 10 in that state. Then, the support 107 is screwed with the screw 11 from below the case, and the bimetal 202 and the movable contact plate 201 are screwed with the screw 12 from above the case to complete the attachment of various components to the case.

In conventional circuit breakers, the movable contact plate, the crossbar, and the frame that holds the link, etc. are provided separately, and it is necessary to place them on the base at the same time. Although this circuit breaker was difficult, it was only necessary to combine the unitized switching mechanism and load side circuit in the case, which greatly improved the assembly workability and improved the production yield. Improvements can be made.

The trip coil and detection circuit are electrically connected separately. Then, attach the cover to the case and complete the circuit breaker assembly.

In addition, the circuit breaker switching mechanism has been configured as a unit, which has the accompanying effect that the size of the switching mechanism in the direction of the power supply-load side can be made more compact than before. A circuit breaker can be provided. In addition, in order to maintain compatibility with conventional circuit breaker dimensions, a high-performance circuit breaker can be built by incorporating an additional function such as a leakage alarm device, an overvoltage detection device, or a break alarm device in the empty space inside the device body. Can be provided.

As described above, the circuit breaker switching mechanism of the present invention is configured by unitizing the parts necessary for switching as much as possible, so that the assembly workability is greatly improved while utilizing the conventional circuit breaker switching mechanism as much as possible. It is possible to provide a circuit breaker switching mechanism that can be improved and can improve the yield during production.

It is the figure which showed the switching mechanism of the circuit breaker of this invention. It is the figure which looked at the switching mechanism of the circuit breaker of the present invention from the lower part. It is an assembly drawing using the switching mechanism of the circuit breaker of the present invention. It is an assembly drawing using the switching mechanism of the circuit breaker of the present invention. It is a figure explaining background art. It is a figure explaining background art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Opening / closing mechanism 101 Operation member 102 Rotating member 1021 Energizing spring 103 of rotating member Link 104 Latch member 105 Actuating plate 106 Crossbar 107 Support body 1071 Engaging portion 1072 Engaging portion 1073 Guide hole 108 Winding spring 201 Movable contact plate 202 Bimetal 203 Power supply side terminal 204 Load side terminal 205 Zero phase current transformer 206 Trip coil 207 Detection circuit 11 Screw 12 Screw

Claims (4)

In a circuit breaker that intervenes in an electric circuit and supplies current, energizes, and interrupts it.
A container comprising a case and a cover constituting the outline of the circuit breaker;
An operation member partially protruding from the body;
An open / close mechanism that operates in conjunction with the operation member by operating the operation member and forcibly contacts and separates the fixed contact and the movable contact, and constitutes the open / close mechanism.
A rotating member disposed in the container so as to be rotatable between an on state and an off state of the circuit breaker by operating the operation member;
A latch member connected to the rotating member by a link, and operating in conjunction with a rotating operation of the rotating member via the link;
An actuating plate with which a portion of the latch member engages;
A cross bar that supports the movable contact and is constantly biased by an elastic member in a direction in which the movable contact is separated from the fixed contact;
An opening / closing mechanism for a circuit breaker, characterized in that it is supported by a substantially U-shaped support.
The point of action of the latch on the crossbar;
The point of action of the elastic body on the crossbar;
And the support part of the elastic body by the support body is arranged on substantially the same straight line,
In the open state of the movable contact, the crossbar is
The circuit breaker switching mechanism according to claim 1, wherein the circuit breaker is held in a state of being pressed against the support by the elastic body.
A winding spring is used as the elastic body, and the support body is provided with an engaging portion that engages with the inside of the winding spring, and the direction in which the cross bar of the cross bar pressed by the winding spring operates 3. The circuit breaker switching mechanism according to claim 2, wherein a locking portion for restricting the movement in the vertical direction is provided.
4. The circuit breaker switching mechanism according to claim 3, wherein the circuit breaker is a two-pole circuit breaker.

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