JP7337569B2 - Electromagnetic trip device for circuit breaker - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic tripping device for a circuit breaker that detects when an excessive current such as a short-circuit current flows in an electric circuit and cuts off the electric circuit.

Conventionally, a circuit breaker is sometimes provided with an electromagnetic tripping device that detects when an excessive current such as a short-circuit current flows in an electric circuit and operates to cut off the electric circuit (for example, Patent Document 1 ). Here, a conventional electromagnetic tripping device 51 will be briefly described with reference to FIG. The electromagnetic tripping device 51 is a fixed electromagnetic piece 52 that is fixed to the body case of the circuit breaker, and is assembled to the fixed electromagnetic piece 52, and is a movable electromagnetic piece that can change its posture between a normal posture and a breaking posture. 53, and an extension spring 54 formed like a coil spring interposed between the fixed electromagnetic piece 52 and the movable electromagnetic piece 53, and the like. The tension spring 54 has one end hooked to the fixed electromagnetic piece 52 and the other end hooked to the movable electromagnetic piece 53, and urges the movable electromagnetic piece 53 toward the normal posture side by the load in the contracting direction. In such an electromagnetic tripping device 51, when a current exceeding a predetermined value flows through the electric circuit arranged in the circuit breaker, the movable electromagnetic piece 53 resists the urging force of the tension spring 54 and cuts off from the normal posture. When the attitude of the movable electromagnetic piece 53 is changed, an interruption mechanism (not shown) operates in accordance with the attitude change of the movable electromagnetic piece 53, thereby interrupting the electric circuit. 55 is a coil portion for generating an electromagnetic force that attracts the movable electromagnetic piece 53 when an excessive current flows, and 56 is an iron core installed so as to penetrate the coil portion.

JP 2015-170383 A

However, the above-described conventional electromagnetic tripping device has a problem that the assembly work, especially the installation work of the tension spring, is troublesome.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an electromagnetic tripping device for a circuit breaker that is easier to assemble than the conventional one.

In order to achieve the above object, the present invention provides a fixed electromagnetic piece fixed to a main body case of a circuit breaker, and a fixed electromagnetic piece assembled to the fixed electromagnetic piece so that the attitude can be changed between a normal attitude and an interruption attitude. a movable electromagnetic piece; and an urging means interposed between the fixed electromagnetic piece and the movable electromagnetic piece for urging the movable electromagnetic piece toward the normal posture side; a circuit that is installed in an electric circuit installed in the electric circuit, and when a current exceeding a predetermined value flows through the electric circuit, the movable electromagnetic piece changes its posture from the normal posture to the interrupting posture against the biasing force of the biasing means. In the electromagnetic tripping device for a circuit breaker, the fixed electromagnetic piece has a plate-like portion extending in a vertical direction, an opening is formed in the plate-like portion, and the movable electromagnetic piece is connected to the opening. is attached to the fixed electromagnetic piece in a state of penetrating through, and the upper edge of the opening of the fixed electromagnetic piece is provided with a first fitting projection projecting downward toward the movable electromagnetic piece. On the other hand, a second fitting protrusion protruding upward toward the first fitting protrusion side is provided at a position facing the first fitting protrusion on the movable electromagnetic piece, and is formed in the shape of a coil spring. A compression spring is provided as the urging means in a state in which the first fitting projection is fitted on one end side and the second fitting projection is fitted on the other end side, respectively.

According to the present invention, the fixed electromagnetic piece has the plate-like portion extending in the vertical direction, the opening is formed in the plate-like portion, and the movable electromagnetic piece is attached to the fixed electromagnetic piece while passing through the opening. In the assembled one, the upper edge of the opening of the fixed electromagnetic piece is provided with a first fitting projection projecting downward toward the movable electromagnetic piece side, while the movable electromagnetic piece is provided at a position facing the first fitting projection. , a second fitting protrusion protruding upward toward the side of the first fitting protrusion. As biasing means for biasing the movable electromagnetic piece toward the normal posture side, a compression spring formed in the shape of a coil spring is fitted with a first fitting projection on one end and a second fitting projection on the other end. It was set in a state where Therefore, compared with the conventional electromagnetic tripping device which employs a tension spring as a biasing means and hooks both ends of the tension spring to a fixed electromagnetic piece or a movable electromagnetic piece, respectively, the installation of the biasing means and the It is possible to easily assemble the electromagnetic tripping device.

FIG. 4 is a perspective explanatory view showing the circuit breaker from which the cover member has been removed; It is explanatory drawing which showed the cross section in the front-back direction of a circuit breaker. 1 is a perspective explanatory view showing an electromagnetic tripping device according to the present invention; FIG. It is a perspective explanatory view showing a conventional electromagnetic tripping device.

A circuit breaker equipped with an electromagnetic tripping device according to an embodiment of the present invention will be described in detail below with reference to the drawings.
FIG. 1 is a perspective explanatory view showing a circuit breaker 1 from which a cover member has been removed. FIG. 2 is an explanatory diagram showing a cross section of the circuit breaker 1 in the front-rear direction. FIG. 3 is a perspective explanatory view showing the electromagnetic tripping device 11. As shown in FIG.

The circuit breaker 1 has a main body case made of synthetic resin, in which a cover member (not shown) is attached to a base 2 so as to cover the upper part thereof. Side terminals 4 are provided, and load side terminals 3 are provided at the front. Also, on the base 2, three electric lines extending in the front-rear direction are arranged side by side in order to electrically connect the load-side terminals 3 and the power-side terminals 4. As shown in FIG. Each electric circuit has a first fixing bracket 5 extending rearward from the load-side terminal 3 and serving as one component of the front electric circuit, and a fixed contact 7 provided at the front end thereof, and extending forward from the power-side terminal 4 to constitute the rear electric circuit. A second fixed metal fitting 6 and a movable contact 8 are provided at the rear end. is provided with a movable contact member 10 or the like for electrically connecting/disconnecting the

Further, a breaking mechanism 9 for operating the movable contact member 10 and an operation part 24 for operating the breaking mechanism 9 are provided for each electric circuit. In addition, an electromagnetic tripping device 11 is installed in the front electrical path and operates when an excessive current such as a short-circuit current flows through the electrical path. In the circuit breaker 1, when an excessive current exceeding a predetermined value flows in the electric circuit, the electromagnetic tripping device 11 operates and the operating portion 24 operates. , the movable contact member 10 moves in the direction in which the movable contact 8 is separated from the fixed contact 7, and finally the electric circuit is cut off. 31 is a handle for turning on/off the electric circuit by actuating the movable contact member 10 via the breaker mechanism 9 .

Here, the electromagnetic tripping device 11, which is the essential part of the present invention, will be described in detail.
The electromagnetic tripping device 11 includes a yoke 21 functioning as a fixed electromagnetic piece, a movable electromagnetic piece 22 assembled to the yoke 21, a compression spring 23 interposed between the yoke 21 and the movable electromagnetic piece 22, and an excessively large spring. It is provided with a coil portion 55 or the like that generates an electromagnetic force for attracting the movable electromagnetic piece 22 when an electric current flows. The yoke 21 has a plate-like main body 25 extending in the vertical direction, and a connecting portion 26 that is bent forward from the lower end of the main body 25 and into which the iron core 56 of the coil portion 55 can be inserted. An opening 27 is formed in the upper portion of the main body 25, and a portion of the upper edge of the opening 27, which is approximately the center in the left-right direction, protrudes downward (toward the inside of the opening 27 and toward the movable electromagnetic piece 22, which will be described later). A first fitting projection 28 is provided for the purpose. The yoke 21 is fixed to the base 2 in such a manner that the thickness direction of the main body 25 is the front-rear direction. In addition, reference numeral 30 denotes fixing pieces for fixing the yoke 21 to the base 2, which are provided on the left and right side edges of the lower portion of the main body 25, respectively.

On the other hand, the movable electromagnetic piece 22 is a metal piece integrally having an attracted portion 22a extending forward and an acting portion 22b extending downward from the base end portion of the attracted portion 22a. 21, and the to-be-attracted portion 22a protrudes forward from the main body 25 of the yoke 21 through the opening 27, i.e., penetrates the opening 27 of the yoke 21 in the longitudinal direction. Assembled. In addition, at the base end of the acting portion 22b (on the connection side with the sucked portion 22a), at a position facing the first fitting projection 28 when assembled to the yoke 21, an upper portion (on the side of the first fitting projection 28) is provided. ) is provided. Furthermore, the compression spring 23 formed in the shape of a coil spring connects the yoke 21 and the movable electromagnetic piece 22 in a state in which a first fitting projection 28 is fitted on one end and a second fitting projection 29 is fitted on the other end. The movable electromagnetic piece 22 is urged toward the normal posture side (the side separating the attracted portion 22a from the iron core 56) by the load in the extending direction.

In the electromagnetic tripping device 11, when a current exceeding a predetermined value flows through the electric circuit, the movable electromagnetic piece 22 changes its posture from the normal posture to the blocking posture against the biasing force of the compression spring 23 (specifically, , the chucked piece 22a is in a forward leaning posture where the iron core 56 is chucked). Accompanying this change in posture, the action portion 22b interferes with and operates the operation portion 24, and with the operation of the operation portion 24, the breaking mechanism portion 9 and, in turn, the movable contact member 10 operate to break the electric circuit. become.

According to the electromagnetic tripping device 11 configured as described above, the movable electromagnetic piece 22 is assembled to the yoke 21 in such a state as to pass through the opening 27 formed in the yoke 21 in the front-rear direction. , the upper edge of the opening 27 of the yoke 21 is provided with a first fitting projection 28 projecting downward, while the movable electromagnetic piece 22 projects upward at a position facing the first fitting projection 28 . A second mating projection 29 is provided. As biasing means for biasing the movable electromagnetic piece 22 toward the normal posture side, a compression spring 23 formed in the shape of a coil spring is provided with a first fitting projection 28 on one end side and a second fitting projection on the other end side. 29 are fitted in each other. Therefore, the conventional electromagnetic tripping device employs a tension spring as biasing means for biasing the movable electromagnetic piece toward the normal position, and hooks both ends of the tension spring to the fixed electromagnetic piece and the movable electromagnetic piece, respectively. , the installation of the biasing means and the assembly of the electromagnetic tripping device 11 can be easily performed.

The configuration of the electromagnetic tripping device of the circuit breaker of the present invention is not limited to the above-described embodiment. , can also be changed as appropriate without departing from the gist of the present invention.

For example, in the above embodiment, the first fitting projection projects downward and the second fitting projection projects upward, respectively. In some cases, the first fitting projection may project upward and the second fitting projection may project downward. The design can be changed as appropriate.
In the above-described embodiment, the mounting posture of the compression spring is substantially parallel to the vertical direction, and the urging force of the compression spring acts substantially in the vertical direction. The mounting posture of the compression spring can also be changed as appropriate in relation to the specific projecting direction of the fitting projection 2. For example, by inclining the first fitting projection and the second fitting projection in the front-rear direction, It is also possible to configure the mounting posture of the compression spring to be inclined forward and backward from the vertical direction so that the urging force of the compression spring acts in the inclined direction.

DESCRIPTION OF SYMBOLS 1--circuit breaker, 2--base (main body case), 9--breaking mechanism part, 11--electromagnetic tripping device, 21--yoke (fixed electromagnetic piece), 22--movable electromagnetic piece, 22a... to-be-adsorbed part, 22b... action part, 23... compression spring, 24... operation part, 25... body, 27... opening, 28... first fitting projection, 29... second Fitting protrusion, 55... Coil part, 56... Iron core.

Claims (1)

A fixed electromagnetic piece fixed to a body case of a circuit breaker, a movable electromagnetic piece assembled to the fixed electromagnetic piece and capable of changing its posture between a normal posture and a breaking posture, the fixed electromagnetic piece and the movable biasing means interposed between the electromagnetic piece and biasing the movable electromagnetic piece toward the normal posture side,
When a current exceeding a predetermined value flows in the electric circuit arranged in the main body case, the movable electromagnetic piece is cut off from the normal posture against the biasing force of the biasing means. An electromagnetic trip device for a circuit breaker that changes attitude to attitude,
The fixed electromagnetic piece has a plate-like portion extending in the vertical direction, and an opening is formed in the plate-like portion,
The movable electromagnetic piece is attached to the fixed electromagnetic piece in a state of penetrating the opening ,
The upper edge of the opening of the fixed electromagnetic piece is provided with a first fitting projection projecting downward toward the movable electromagnetic piece side, while facing the first fitting projection of the movable electromagnetic piece. is provided with a second fitting projection projecting upward toward the first fitting projection side,
A compression spring formed in the shape of a coil spring is provided as the urging means in a state in which the first fitting projection is fitted on one end side and the second fitting projection is fitted on the other end side, respectively. Electromagnetic trip device for circuit breaker.

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