JP2000200535A - Circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To intend the reduction in size and in the number of part items by constituting an arc extinguishing device with an electromagnetic frame constituting a magnetic circuit of an electromagnetic coil. SOLUTION: In this circuit breaker provided with a case 1, a rotatable operation handle 2; a fixed contact 3 fixed to the case 1 and provided with a fixed contact; a movable contact disposed opposedly to the fixed contact on one end; a movable contact 4 having a rotational shaft support point on the other end; a bimetal trip device 5 for open-triggering the movable contact from the fixed contact and an electromagnetic trip device 6 by abnormal large current; and an open/close mechanism part that is manually openable by the operation handle 2 and forcedly operates the movable contact 4 in a open state by the bimetal trip device 5 and the electromagnetic trip device 6 by the operation handle 2 even if the contacts are in closed state, both ends of an electromagnetic coil of the electromagnetic trip device 6 are connected between a power source side connecting terminal 8 and the fixed contact 3, the electromagnetic trip device 6 is disposed in the space between a contact device constituted of the movable contact and the fixed contact and a handle operation face so that a part of the electromagnetic frame of the electromagnetic trip device 6 is to be an arc extinguishing device.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker,
The present invention relates to a technology for reducing the size and the number of parts without reducing performance.

[0002]

2. Description of the Related Art Conventionally, this type of circuit breaker has the configuration shown in FIG. 50 is a case 50a and a cover 5
Ob, a synthetic resin box, 51 is a movable contact set in the case and has a movable contact 51a, and 52 is a fixed contact fixed to the case and has a fixed contact 52a.
In the vicinity of the contact portion, an arc extinguishing plate 53 and an arc extinguishing wall 54 for sucking and cooling an arc generated between the contacts at the time of opening / closing and interruption constitute a known deion arc extinguishing device.

[0005] Reference numeral 55 denotes an electromagnetic coil, which forms an electromagnetic trip device by an electromagnetic frame 56, a movable iron piece 57 and the like. Reference numeral 58 denotes a handle, which is fixed to a mechanism (not shown). 59
Has a contact portion 59a with the movable iron piece and an engaging portion 59b engaged with the mechanism portion. The details of the ON / OFF operation by the handle and the trip operation by the electromagnetic trip device when an abnormal current flows in the circuit have already been described in many patents and utility model applications. Description is omitted. Conventionally, in the circuit breaker having the above-described configuration, the electromagnetic trip device and the arc extinguishing device are separately installed and have a structure including separate components.

[0004]

Since the electromagnetic trip device and the arc extinguishing device are separately configured, the number of components is large, and it is necessary to secure separate mounting spaces for each device, making it difficult to reduce the size. . Therefore, the present invention aims to provide a circuit breaker that integrates an electromagnetic trip device and an arc extinguishing device, reduces the number of parts without reducing the breaking performance, reduces the number of parts, and improves the assemblability. is there.

[0005]

In order to achieve the above object, first, in the first aspect, a rotatable operation handle for turning on and off a case and a contact device, and a fixed contact fixed to the case. The fixed contact provided, a movable contact disposed at one end opposed to the fixed contact, a movable contact having a rotating shaft support at the other end, and the movable contact is separated from the fixed contact by the magnitude of the abnormal current. Bimetal tripping device and electromagnetic tripping device that triggers opening can be manually opened and closed with an operation handle, and the operation handle allows the bimetal tripping device and the electromagnetic tripping device to trigger even when the contacts are closed. In a circuit breaker having an open / close mechanism for forcibly operating a movable contact in an open state, both ends of an electromagnetic coil of the electromagnetic trip device are connected between a connection terminal on a power supply side and a fixed contact. While, and electromagnetic tripping equipment placement in the space between the contact device and the steering surfaces constituting the fixed contact and the movable contact, a portion of the electromagnetic frame of the electric 磁引 release device was extinguishing device.

In the second aspect, the electromagnetic trip device is fixed by connecting the electromagnetic frame to the fixed contact by welding or riveting and fixing the fixed contact to the case 1.

[0007]

According to the configuration of the first aspect, the arc between the contacts generated when the contacts are opened is attracted and cooled by the electromagnetic frame by the electromagnetic frame constituting the electromagnetic tripping device. In addition, an arc-extinguishing plate to be incorporated in the arc-extinguishing device becomes unnecessary, and the number of parts can be reduced. In the past, the arc extinguishing device and the electromagnetic trip device were installed in separate mounting spaces, but an electromagnetic coil was placed between the connection terminal on the power supply side and the fixed contact,
Since the electromagnetic trip device is arranged between the contact device and the handle operation surface, the size can be significantly reduced.

According to the second aspect of the present invention, since the fixed contact fixed to the case is connected to the electromagnetic trip device by welding or swaging, the fixed contact is fixed to the case and the electromagnetic trip device is fixed. Can be positioned and fixed, and the number of assembling steps can be reduced by improving the assembling workability as compared with the case of separately fixing to the case.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to FIGS. FIG. 2 shows the configuration of the first embodiment of the present invention. This circuit breaker includes a case, a contact device,
Opening / closing mechanism, electromagnetic trip device, bimetal trip device,
FIG. 2 is a cross-sectional view of a circuit breaker, and FIG. 3 is a front view and a side view of an electromagnetic trip device. The case 1 includes a base 1a and a cover 1b, and is formed in a substantially box shape with an insulating material such as a phenol resin, for example, and incorporates a power supply side connection terminal 8 outside a pair of left and right side walls 1c and 1d in FIG. It has a terminal device mounting portion 1f for incorporating the mounting portion 1e of the terminal device and the connection terminal 9 on the load side.
The terminal devices on the power supply side and the load side have a terminal fitting 10 of a box body and a terminal screw 11 screwed to the terminal fitting.

The contact device opens and closes an electric circuit, and includes a fixed contact 3 and a movable contact 4. The fixed contact 3 is formed by bending a conductive material. The fixed contact 3 is attached to the fixed contact 3 a, the electromagnetic coil 6 a of the electromagnetic tripping device 6 is connected to the electromagnetic coil 6 a, and the electromagnetic frame 6 c constituting the electromagnetic tripping device 6. And a connection portion 3c for the power supply, and is disposed in the vicinity of the bottom surface side 1h on the power supply side. The fixed contact 3 is arranged such that the contact surface faces from the bottom surface of the circuit breaker to the handle operation surface side.

The movable contact 4 has a movable contact 4a at one end and a rotating shaft support 4b at the other end. At a substantially central portion, a contact portion 4c with a pressing member 12 that moves back and forth between the handle operation surface and the case bottom surface by an opening / closing mechanism that interlocks with the operation handle 2 is provided. The rotary shaft support 4b is provided with a contact spring 13 which is fixed to the case by a shaft 14 and applies a rotational force in a direction to open the movable contact 4a from the fixed contact 3a.

The opening / closing mechanism has a mechanism for opening and closing the fixed contact 3a and the movable contact 4a by the operating handle 2, and forcibly opening the contact when an abnormal current flows.

The electromagnetic trip device 6 operates an opening / closing mechanism when a short-circuit current is detected to open the movable contact 4a from the fixed contact 3a. The electromagnetic coil 6a, the electromagnetic frame 6
b, 6c, a suction member 6b, and an interlocking member 16 for operating the tripping member 15. One end of the electromagnetic coil 6a is connected to the connection terminal 8 on the power supply side, and the other end is connected to the fixed contact 3b. ing.

More specifically, the electromagnetic frame 6b is formed in an inverted U-shape, houses the suction member 6d and the electromagnetic coil 6a, and is connected to another electromagnetic frame 6c by welding or caulking. The electromagnetic trip device including the electromagnetic frames 6b and 6c is disposed in a space between the contact device including the movable contact 4a and the fixed contact 3a and the handle operation surface 1b.

The electromagnetic frame 6c greatly extends from the electromagnetic trip device 6 to the fixed contact 3c side, and is connected to the fixed contact 3c near the fixed contact 3a by welding or swaging. Therefore, first, the electromagnetic trip device 6 can be positioned and fixed to the case by fixing the fixed contact 3 to the case.

Second, the electromagnetic frame 6c generates an arc generated between the contacts when the short-circuit current is interrupted by the magnetism of the electromagnetic frame 6c.
As shown in FIG. 4 and FIG.
The process is shifted to the electromagnetic frame 6C to cool and extinguish the arc. That is, a part of the electromagnetic frame 6c can be used as an arc extinguishing device.

The interlocking member 16 has, at one end, an engaging portion 16a which engages with the suction member 6d, and at the other end, a contact portion 16b which trips the opening / closing mechanism and contacts the tripping member 15a. A rotation shaft support 1 serving as a fulcrum of rotation is provided substantially in the center.
6c is provided.

The tripping member 15 mainly comes into contact with a contact portion 15b which comes into contact with the bimetal tripping element 5 operated by overcurrent, and a contact with an interlocking member 16b attached to the electromagnetic tripping device 6 operated by short-circuit current. A portion (not shown) having a portion 15a and an engaging portion (not shown) that engages with the opening and closing mechanism at a substantially central portion, and a rotating shaft support portion on the bottom side of the case 1 to constitute the opening and closing mechanism. It is fixed to the shaft. An adjusting member 17 for adjusting the distance from the bimetal is screwed into the contact portion 15b with the bimetal.

Next, the operation when the circuit breaker is opened will be described below. When a short-circuit current flows through the circuit breaker of FIG. 2 in which the movable contact 4a and the fixed contact 3a are closed,
An electric current flows through the electromagnetic coil section 6a, and a strong magnetic flux is generated, and the suction member 6d performs a suction operation. At the same time, the interlocking member 16a engaged with the suction member 6d rotates counterclockwise around the rotation shaft support 16c as a fulcrum, and moves the tripping member 15 engaged with the opening / closing mechanism toward the case 1d on the load side. Let it work,
At the same time as the operation handle 2 rotates in the opening direction, the movable contact 4 rotates clockwise by the urging force of the contact spring 13 with the movable contact 4 being the fulcrum, and the movable contact 4 a and the fixed contact 3 a are opened. You.

The occurrence of an arc when the movable contact 4a and the fixed contact 3a are opened will be described in more detail with reference to FIGS. FIG. 4 shows a state diagram when the movable contact 4a and the fixed contact 3a start opening. In this state, the distance L2 between the movable contact 4a and the fixed contact 3a is smaller than the distance L1 between the electromagnetic frame 6c constituting the electromagnetic trip device and the movable contact 4, and the arc resistance is also small. Therefore, the movable contact 4a and the fixed contact 3a are small. An arc occurs between them.

FIG. 5 shows a state in which the movable contact 4a and the fixed contact 3a are completely opened. In this state, the movable contact 4
The distance L2 between the fixed contact 3a and the fixed contact 3a is larger than the distance L1 between the electromagnetic frame 6c and the movable contact 4 constituting the electromagnetic trip device 6, and the arc resistance is large. Therefore, in FIG. 4, the distance between the movable contact 4a and the fixed contact 3a is large. The generated arc moves to the movable contact 4 and the electromagnetic frame 6c, and is cooled and extinguished. Therefore, the arc generation time between the movable contact 4a and the fixed contact 3a is short, and the effect of reducing contact wear is obtained. The electromagnetic frame 6c has a function of configuring a magnetic circuit of the electromagnetic trip device 6, and also has a function of an arc extinguishing device that extinguishes an arc generated when a contact is opened.

FIG. 6 shows a state where the arc extinguishing wall 18 is incorporated in the arc extinguishing device 7. The arc-extinguishing wall 18 prevents the case from burning due to the arc generated when the contacts are opened and closed, and prevents the insulation performance from deteriorating due to the generation of conductive decomposed substances (eg, carbides). FIG. 7 shows another embodiment, which shows an electromagnetic trip device in which the electromagnetic frames 6b and 6c are integrated.

[0023]

According to the first aspect of the present invention, the electromagnetic frame of the electromagnetic tripping device and the magnetic member constituting the arc extinguishing device, which have been conventionally separately constructed, are integrated, and the contact device and the handle are provided. Since the components are integrated in a space with the operation surface, the number of parts can be reduced and the outer shape can be significantly reduced.

According to the second aspect of the present invention, since the electromagnetic trip device is connected to the fixed contact fixed to the case, the fixed contact and the electromagnetic trip device which had to be separately attached to the case in the past can be used once. And the number of assembling steps can be reduced.

[0025]

[Brief description of the drawings]

FIG. 1 shows an embodiment of a conventional circuit breaker.

FIG. 2 is a sectional view of a circuit breaker showing a first embodiment of the present invention.

FIG. 3 is a front view and a side view of an electromagnetic trip device.

FIG. 4 is a state diagram of a contact opening start

FIG. 5 is a state diagram when a contact is opened.

FIG. 6 is a state diagram in which an arc-extinguishing wall is incorporated.

FIG. 7 is a front view and a side view of another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Case 2 Handle 3 Fixed contact 4 Movable contact 5 Bimetal 6 Electromagnetic tripping device 7 Arc extinguishing device 8 Power supply side connection terminal 9 Load side connection terminal 10 Terminal fitting 11 Terminal screw 12 Pressing member 13 Contact spring 14 Rotating shaft 15 Tripping member 16 Interlocking member 17 Adjusting member 18 Arc extinguishing wall

Claims (2)

[Claims] A rotatable operation handle for turning on and off the case and the contact device; a fixed contact fixed to the case and provided with a fixed contact; and a movable contact disposed at one end against the fixed contact. A movable contact having a rotating shaft support at the other end,
Depending on the magnitude of the abnormal current, a bimetal trip device and an electromagnetic trip device that trigger the opening of the movable contact from the fixed contact can be manually opened and closed with an operation handle. In a circuit breaker having an opening / closing mechanism for forcibly operating a movable contact in an open state by a trigger of a bimetal trip device and an electromagnetic trip device, the circuit breaker is provided between a connection terminal on a power supply side and a fixed contact. While connecting both ends of the electromagnetic coil of the electromagnetic trip device, an electromagnetic trip device is disposed in a space between the contact device constituted by the movable contact and the fixed contact and the handle operation surface, and the electromagnetic frame of the electromagnetic trip device is A circuit breaker characterized in that a part thereof is an arc extinguishing device. 2. The circuit according to claim 1, wherein said electromagnetic frame is connected to a fixed contact by welding or swaging, and said fixed contact is fixed to a case, thereby fixing an electromagnetic trip device. Circuit breaker. [0001]