JP2002093299A - Circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-cost circuit breaker capable of easily setting the positional relation between a trip bar and a trip button and having a simple constitution of the trip bar and the trip button even in a circuit breaker having different number of poles such as a two-pole and a three-pole. SOLUTION: This circuit breaker is provided with the trip bar 20 driven by the operation of a thermal tripper 31 and a electromagnetic tripper 32, a switch mechanism part 12 operated by the turning trip bar, and a manual tripping means turning the trip bar by the external manual operation. The manual tripping means is constituted of the trip bar 20 formed of a round rod and the trip button 22 abutting on the trip bar and turning the trip bar 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker, and more particularly to a tripping device for a circuit breaker having a trip button which can be manually tripped.

[0002]

2. Description of the Related Art FIG. 4 is a side sectional view showing the inside of a conventional circuit breaker shown in, for example, Japanese Patent Application Laid-Open No. 8-96689, with a part thereof broken. In the figure, 1 is a base and 2 is a cover. Reference numeral 3 denotes an overcurrent trip device, which is attached to the base 1 via a relay terminal 4 with screws 5. The overcurrent tripping device 3 includes a heater 6 electrically connected to the relay terminal 4 by a screw 14, a thermal tripping device 31 including a yoke 8 and a bimetal 9 fixed to the heater 6 with rivets 7, The yoke 8 is arranged to face the yoke 8 by an electromagnetic force generated by a current flowing through the heater 6.
And an electromagnetic trip device 32 including a spring 11 for returning the armature 10 to the armature 10.

Reference numeral 12 denotes an opening / closing mechanism, which comprises a trip bar 12a rotatably held by a latch (not shown), a latch 12c, a lever 12d, and the like. Further, in such a circuit breaker, an operation of releasing the set state of the overcurrent trip device 3 without actually flowing an overcurrent is performed in order to test whether the switching mechanism unit 12 operates normally. A trip button (not shown) is provided near the upper portion of the cover 2 as a manual tripping means that can be manually tripped from the outside of the cover 2 so as to perform the operation.

In such a conventional circuit breaker,
Normally, a current equal to or less than the rated current value flows through the overcurrent trip device 3. Here, if the current flowing through the overcurrent trip device 3 rises above the rated current for some reason, the bimetal 9 is heated by the Joule heat generated from the heater 6, and the open end 9a is bent in the direction of arrow A. Press the trip bar 12a. When the trip bar 12a is pressed by a predetermined amount or more, the trip bar 12a rotates to operate the opening / closing mechanism unit 12, and the movable contact 13a is fixed to the fixed contact 13b.
And the circuit is interrupted.

When the current flowing in the overcurrent tripping device 3 is equal to or higher than the rated current and equal to or higher than a predetermined value, the magnetic flux generated by the current flowing through the heater 6 and passing through the yoke 8 and the armature 10 causes Is generated in the direction of the yoke 8. This suction force exceeds the urging force of the spring 11 for returning the armature 10, sucks the armature 10, pushes the trip bar 12a at the tip end 10a, rotates the trip bar 12a clockwise, and the opening / closing mechanism 12 moves. Activated, the movable contact 13a is separated from the fixed contact 13b, and the circuit is cut off.

Further, by pushing down a trip button (not shown), which is not shown, but can be operated manually, against the urging force of a return spring (not shown),
By pushing the trip bar 12a and rotating the trip bar 12a to activate the opening / closing mechanism 12, the movable contact 13a is separated from the fixed contact 13b.
Can be tested without actually passing current.

[0007]

In the conventional circuit breaker as described above, a thermal trip device 31, an electromagnetic trip device 32, a manual trip means (not shown) using a trip button and an accessory device (FIG. In order to cope with various types of tripping means such as tripping (not shown), it is necessary to form a trip bar of a complicated shape. In a multi-pole circuit breaker having a different number of poles, such as a two-pole product or a three-pole product, the position or shape of the contact surface must be changed for each different number of poles. Was.

The present invention has been made in order to solve such a problem. Even in a multi-pole circuit breaker having a different number of poles, such as a two-pole product or a three-pole product, the relationship between the trip bar and the trip button is determined. It is an object of the present invention to provide an inexpensive circuit breaker that can be easily set and has a simple configuration of a trip bar and a trip button.

[0009]

A circuit breaker according to the present invention is operated by a thermal trip device which bends in response to an electric current and an electromagnetic force generated when the electric current exceeds a predetermined value. An electromagnetic trip device, a trip bar driven by the operation of the thermal trip device and the electromagnetic trip device, an opening / closing mechanism operated by rotation of the trip bar, and turning of the trip bar by manual operation from outside. In the circuit breaker provided with a manual tripping means for moving the trip bar, the manual tripping means comprises a trip bar formed of a round bar, and a trip button which comes into contact with the trip bar and rotates the trip bar. is there.

Further, the trip button is provided with an inclined surface for rotating the trip bar by contacting the trip bar when the trip button is pressed.

Further, the trip button is formed with a semi-cylindrical portion, and the semi-cylindrical portion is provided with a concave portion and a projection for receiving a return spring for returning the trip button to a predetermined position.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a front view showing the inside of a circuit breaker according to an embodiment of the present invention with a part broken away. FIGS. 2A and 2B are enlarged cross-sectional views of a main part showing a relationship between a trip button and a trip bar, where FIG. 2A is a front view and FIG. 2B is a left side view. FIG. 3 is an enlarged perspective view showing the trip button. In the figure, reference numerals 1 to 14 are the same as those of the above-mentioned conventional apparatus, and the description thereof is omitted.

Reference numeral 20 denotes a trip bar, as shown in FIG. 2, which is formed of a round bar made of an insulating material such as synthetic resin or ceramics. Reference numeral 21 denotes a latch, which is fitted into the trip bar 20 as shown in FIG. 2 and is fixed to a predetermined position of the trip bar 20 in the axial direction.

Reference numeral 22 denotes a trip button. As shown in FIG. 3, a cylindrical head 22a and a semi-cylindrical body 22b are provided.
A concave portion 22c formed in the body portion 22b, into which a return spring 23 described later is inserted, projections 22d, 22e holding both ends of the return spring 23, and a stopper 22f for retaining the protrusion from the body portion 22b; An inclined surface 22g is formed at the end of the body portion 22b to contact and press the circumferential surface of the trip bar 20 when the trip button 22 is pressed down, and is disposed above the trip bar 20 as shown in FIGS. It is configured to be.

Reference numeral 23 denotes a return spring for returning the trip button 22 to a predetermined position when there is no external force for pushing the trip button 22 down. The trip button 2
2, the return spring 23 and the trip bar 20 form a manual tripping means.

In the circuit breaker constructed as described above, in order to test whether or not the switching mechanism 12 normally trips, it is necessary to manually operate the trip button 2 in FIG.
When the button 2 is pushed down in the direction of arrow B, the inclined surface 22g of the trip button 22 comes into contact with the circumferential surface of the trip bar 20, and the trip bar 20 is rotated clockwise about the shaft 24. Due to the rotation of the trip bar 20, the latch 21 is disengaged from the latch 21c and the lever 12d, and the opening / closing mechanism 12 is operated to move the movable contact 13a to the fixed contact 13b.
Can be separated.

According to the configuration of the circuit breaker of the first embodiment, since the trip bar 20 is formed of a round bar,
The trip button 22 can be disposed so as to abut on an arbitrary position in the axial direction of the trip bar 20, and the trip button 22 can be easily attached to a circuit breaker having a different number of poles.

Further, the body 22b of the trip button 22 is formed in a semi-cylindrical shape, and the semi-cylindrical portion is provided with a concave portion 22c into which a return spring 23 is inserted, and both ends of the concave portion 22c hold both ends of the return spring 23. Before the trip button 22 is incorporated into the cover 2 by providing the projections 22d and 22e
The trip button 22 and the return spring 23 can be easily combined. By incorporating this into the cover 2, a force for urging the return spring 23 toward the upper surface of the cover 2 is generated. In addition, the stopper 22f is connected to the trip button 22.
Is depressed against the urging force of the return spring 23.

[0019]

Since the present invention is configured as described above, it has the following effects.

The manual tripping means is constituted by a trip bar formed of a round bar and a trip button for rotating the trip bar by contacting the trip bar.
Since the disposition position of the trip button can be set so as to abut on an arbitrary position in the axial direction of the trip bar, the trip button can be easily attached to a circuit breaker having a different number of poles.

Further, the trip button is provided with an inclined surface for rotating the trip bar by contacting the trip bar when the trip button is pressed, so that the trip bar can be directly driven, and the shape of the trip bar can be simplified. Become.

Furthermore, the trip button is formed in a semi-cylindrical shape, and the semi-cylindrical portion is provided with a concave portion and a projection for inserting a return spring for returning the trip button to a predetermined position. Before assembling, the trip button and return spring can be easily combined,
It is possible to prevent the return spring from coming off before being assembled into the cover.

[Brief description of the drawings]

FIG. 1 is a front view showing the inside of a circuit breaker according to a first embodiment of the present invention with a part broken away.

FIG. 2 is an essential part enlarged sectional view showing a relationship between a trip button and a trip bar according to the first embodiment of the present invention.

FIG. 3 is an enlarged perspective view showing a trip button according to the first embodiment of the present invention.

FIG. 4 is a front view showing the inside of a conventional circuit breaker with a part cut away.

[Explanation of symbols]

Reference Signs List 12 opening / closing mechanism part, 20 trip bar, 22 trip button, 22b trunk part (semi-cylindrical part), 22c concave part, 22d, 22e projection, 22g inclined surface, 23 return spring, 31 thermal release device, 32 electromagnetic release apparatus.

Claims (3)

[Claims] 1. A thermal trip device that bends in response to a current supplied thereto, an electromagnetic trip device that operates by an electromagnetic force generated when the current exceeds a predetermined value, the thermal trip device, A trip bar driven by the operation of the electromagnetic trip device, an opening / closing mechanism operated by rotation of the trip bar, and manual trip means for rotating the trip bar by manual operation from outside. In the circuit breaker, the manual tripping means includes a trip bar formed of a round bar, and a trip button that contacts the trip bar and rotates the trip bar. 2. The trip button is provided with an inclined surface which contacts the trip bar and rotates the trip bar when the trip button is pressed.
The described circuit breaker. 3. The trip button is formed with a semi-cylindrical portion,
3. The circuit breaker according to claim 1, wherein the semi-cylindrical portion is provided with a concave portion and a projection for receiving a return spring for returning the trip button to a predetermined position.