JPH09147722A - Interlocking trip device for multipolar circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an interlocking trip device for multipolar circuit breaker reducing the number of part items and assembling man-hours and capable of obtaining a stable trip interlocking action. SOLUTION: This interlocking trip device for multipolar circuit breaker incorporates circuit breakers 2 of individual poles corresponding to phases U, V, W in a resin case 1 partitioned by intermediate partition walls, and it incorporates a rotary trip interlocking rod 3 provided with coupling arms 3b, 3c and a return spring 3e in the resin case 1 to link an opening/closing mechanism and an overcurrent trip device together astride the circuit breakers 2 of individual poles. The coupling arms 3b, 3c corresponding to individual poles and the return spring 3e exciting the interlocking rod 3 at the neutral position are fitted to the interlocking rod 3 arranged astride individual poles in common as one rod, and the shaft ends of the interlocking rod 3 incorporated through the through holes 1e bored on the intermediate partition walls of the resin case 1 are pivotally supported on bearing sections 1d formed on the side covers 1 of the resin case 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interlocking trip device for a multi-pole circuit breaker composed of a plurality of single-pole circuit breakers each having an opening / closing mechanism and an overcurrent trip device for each pole.

[0002]

2. Description of the Related Art As an interlocking trip device for the above-mentioned multi-pole circuit breaker, a bifurcated engagement is provided so as to connect the switching mechanism and the overcurrent trip device to each other across the circuit breaker of each pole. Equipped with a rotary trip interlocking rod with an arm, divide this interlocking rod into a length corresponding to the circuit breaker of each pole, and then individually divide each interlocking rod into a resin case of the circuit breaker. A structure in which a shaft is supported and the shaft ends of the split interlocking rods are interconnected via a fitting type shaft joint, and a return spring is flexibly fitted and supported on the split connecting rods. Japanese Patent Application No.
-67507 has already been proposed.

[0003]

By the way, the assembly structure of the conventional device proposed above has the following problems in terms of operation function and manufacturing cost. 1) Since the tripping interlocking rod that straddles the single-pole circuit breaker of each pole consists of split interlocking rods that are connected to each other via a mating type shaft coupling, the fitting rattling amount of that shaft coupling and the individual The dimensional accuracy and assembly position accuracy of the split interlocking rod affect the interlocking trip operation of the circuit breaker.

2) Further, since the interlocking rod has a divided structure, the number of parts and the number of assembling steps increase, which increases the manufacturing cost of the circuit breaker. 3) In particular, in order to carry the return spring fitted in the interlocking rod in a bent state before the interlocking rod is installed in the resin case, it is necessary to provide a special spring support guide to the split interlocking rod. Therefore, the shape of the parts becomes complicated and the cost becomes high.

The present invention has been made in view of the above points, and an object thereof is to solve the above-mentioned problems and to achieve a stable trip interlocking operation while reducing the number of parts and the number of assembling steps. An object is to provide an interlocking trip device for a multi-pole circuit breaker.

[0006]

In order to achieve the above object, according to the present invention, a circuit breaker for each pole is incorporated in a resin case partitioned by a partition wall, and a circuit breaker for each pole is provided. In a multipolar circuit breaker in which a rotary trip interlocking rod provided with an engaging arm so as to connect the opening / closing mechanism and the overcurrent tripping device to each other in a resin case is incorporated in a resin case, the interlocking rod is The rod is provided with a bifurcated engagement arm corresponding to each pole on its axis and a return spring for urging the interlocking rod to the neutral position, and the shaft end of the interlocking rod is formed on the side cover of the resin case. It shall be configured to be axially supported by the bearing part.

Further, according to the present invention, it is assumed that the following structure is formed on the basis of the above structure. 1) Open a through hole through which the tripping interlocking rod and the engaging arm protruding from the axis of the interlocking rod pass through in the partition wall of the resin case. 2) As positioning means for holding the tripping interlocking rod at a neutral position against the return spring, a protrusion is provided on the shaft end peripheral surface of the interlocking rod, and a positioning stopper is provided on the bearing portion of the resin case cover facing the protrusion. To provide.

3) The return spring is a torsion coil spring fitted and inserted on the shaft of the interlocking rod, and the two ends of which are protruded on the shaft of the interlocking rod in a state where the coil spring is bent before being assembled in the resin case. With the interlocking rod assembled in the resin case, the other end of the coil spring is removed from the engaging arm while the interlocking rod is assembled in the resin case. The rib-shaped protrusions protruding from the peripheral surface of the bearing portion of the case are used to hold it down.

In the multi-pole circuit breaker having the above structure,
When an overcurrent flows through any one of the plurality of poles and trips, a tripping interlocking rod that interlocks with the tripping rotates and opens the opening / closing mechanism of the other pole through the interlocking rod. In this case, since the tripping interlocking rod is one rod that straddles each pole, it is not affected by the looseness and position accuracy of the shaft joint unlike the split type interlocking rod, and this ensures stable interlocking pulling. Removal operation can be obtained.

For the tripping interlocking rod, the above 1)
By adopting the structure of 3), the number of parts can be reduced.
The tripping interlocking rod can be easily installed in the resin case of the circuit breaker by the number of assembly steps.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. First, in FIG. 1 (a), 1 is a resin case of a multi-pole circuit breaker, 2 is a single pole circuit breaker for 3 poles corresponding to U, V, W phases incorporated in the resin case 1, and 3 is a circuit breaker. Resin case 1 connected to the circuit breaker 2 of each pole
It is a tripping interlock rod incorporated in. Here, the resin case 1 is constructed by two sets of intermediate cases 1b having a partition wall 1a for partitioning the respective poles, and left and right side covers 1c superposed on both ends thereof, and the cover 1c. A bearing portion 1d for axially supporting both ends of the trip interlocking rod 3 is formed on the inner surface of the intermediate cover 1b, and a partition wall 1a for the intermediate cover 1b.
Is a through hole 1e through which the interlocking rod 3 having the structure shown in FIG.
Is open.

Further, in FIG. 1 (b), the trip interlocking rod 3 has one rod shaft 3a and three pairs of engaging members projecting in a bifurcated manner from positions corresponding to respective poles on the shaft of the rod shaft 3a. The joint arms 3b and 3c are composed of a protrusion 3d for neutral positioning formed on the peripheral surface of one shaft end of the rod shaft 3a, and a return spring 3e fitted and inserted in the other shaft end. Then, the return spring 3e is a torsion coil spring, and in the stage before the interlocking rod 3 is assembled in the resin case 1, the both ends of the engagement arms 3b and 3c are fully bent as shown in the figure. Hook it between them to carry it. The end of the coil spring facing the engaging arm 3b is bent into an L shape, and the tip thereof is hooked on the engaging arm 3b.

Next, detailed assembly structures of respective parts for incorporating the trip interlocking rod 3 into the resin case 1 are shown in FIGS. First, in FIG. 2, the intermediate case 1b
The through hole 1e opened in the partition wall 1a is a bifurcated engagement arm 3b, 3c protruding from the interlocking rod 3 as shown in the figure.
It is formed in a notch hole that is one size larger than the outer shape including. Therefore, the interlocking rod 3 can be incorporated into the resin case 1 through the through hole 1e without interfering with the partition wall 1a.

3 (a) and 3 (b), the tripping interlocking rod 3 is shown.
The bearing structure of the resin case 1 is shown in FIG. A positioning stopper 1f for holding the interlocking rod 3 in the neutral position against the return spring (which urges the interlocking rod 3 counterclockwise) 3e is formed on the end surface of the lever.

Further, FIGS. 4A and 4B show a spring locking structure of the resin case 1 with respect to the return spring 3e fitted and inserted in the other end side of the trip interlocking rod 3, as shown in the drawing. A rib-shaped protrusion 1g is formed on the peripheral surface of the bearing 1e formed on the inner wall surface of the side cover 1c so as to protrude in a rib shape and press the end of the return spring 3e. And the trip interlocking rod 3
When assembling into the resin case 1, the return spring 3e is hooked between the engaging arms 3b and 3c in a bent state as described in FIG. After being assembled, one end of the return spring 3e is removed from the engaging arm 3b and moved to the inner wall surface of the cover 1c of the resin case 1, and the L-shaped arm portion thereof is formed into the rib-shaped projection portion 1.
The return spring 3e is pressed against the end face of g to hold the return spring 3e in that position. As a result, the return spring 3e is held at a stable position without being displaced from the assembled position or lifted by the vibration applied during the use of the circuit breaker.

With the assembly structure described with reference to FIGS. 2, 3 and 4, the tripping interlocking rod 3 can be easily incorporated in the resin case 1, and the interlocking rod 3 is stable in the neutral position when incorporated. Will be well retained. Next, the opening / closing mechanism of the circuit breaker of each pole and the opening / closing operation of the movable contact will be described with reference to FIGS. In each drawing, 4 is a fixed contact, 5 is a movable contact, 6 is an operation handle pivotally supported by a support shaft of the resin case 1, 7 is an opening / closing mechanism, and 8 is an electromagnetic solenoid type overcurrent trip device. . The opening / closing mechanism 7 includes a swingable movable contact holder 9 whose one end is pivotally supported by the operation handle 6, and a yoke 8a of the overcurrent trip device 8.
A trip lever 10 whose one end is pivotally supported, an opening / closing spring (tension spring) 11 stretched between the movable contact holder 9 and the tip of the trip lever 10, and a locking lever 12 pivotally supported by the yoke 8a. The locking lever 12 is spring-biased clockwise by a tension spring 13 stretched between the armature 8b of the overcurrent trip device 8 and the operating lever 6 and the movable contact. Child holder 9, open / close spring 11
Constitutes a toggle link mechanism. Further, with respect to the opening / closing mechanism 7 having such a configuration, the above-mentioned tripping interlocking rod 3 is arranged above the locking lever 12 and the engaging arms 3b, 3 are provided.
c projects toward the opening / closing mechanism 7. Here, one engagement arm 3b is the engagement piece 1 of the trip lever 10.
0a of the engaging arm 3c is projected on the rotational locus of the engaging lever 12a of the locking lever 12.

In such a structure, when the movable handle 5 is closed and the operating handle 6 is manually turned counterclockwise from the ON state shown in FIG. 5, the toggle link mechanism operates in reverse, interlocking with this. The movable contact 5 is opened by the spring bias of the opening / closing spring 11 and turned off. Further, when the operation handle 6 is returned to the ON position, the closed state of FIG. 5 is restored. During the opening / closing operation by the operation handle, the trip interlocking rod 3 is held in the neutral position without any interference.

On the other hand, when an overcurrent flows through the circuit breaker and the overcurrent trip device 8 is actuated, the armature 8b strikes the locking lever 12, and the locking lever 12 rotates counterclockwise to engage with it. Engagement piece 1 of piece 12a and trip lever 10
Release the engagement with 0a. As a result, the trip lever 10 rapidly rotates counterclockwise by the spring biasing force of the opening / closing spring 11, and the opening / closing spring 11 itself hooked on the trip lever 10 also moves to the left, so that the pivot fulcrum of the movable contact holder 9 is moved. When it exceeds, the toggle link mechanism is reversed, and the movable contact 5 trips so as to open the contact. The state after this trip operation is shown in FIG. 6, and the movement of each component associated with the trip operation is indicated by an arrow.

When the trip lever 10 rotates counterclockwise in the course of the trip operation, the engaging piece 1 of the trip lever 10 rotates.
0a hits the engaging arm 3b of the tripping interlocking rod 3 in the middle of the pivoting, whereby the interlocking rod 3 pivots clockwise. As a result, the engagement arm 3c of the trip interlocking rod 3 strikes the engagement piece 12a of the locking lever 12 incorporated in the circuit breaker of the other pole which has not yet tripped, and the locking lever 12 is moved counterclockwise. The trip lever 10 to release the restraint.
As a result, the circuit breaker of the other pole also operates in the same manner as the trip operation described above, and all the poles of the multi-pole circuit breaker are interlocked and simultaneously tripped.

[0020]

As described above, according to the structure of the present invention, the tripping interlocking rod is composed of one rod, and the engaging arm that individually corresponds to the circuit breaker of each pole on its axis. By providing the above, there is no influence of rattling of the shaft joint and assembling position accuracy, etc., as compared with the conventional split shaft structure, and it is possible to perform stable interlocking trip operation by connecting all poles at all times. . Furthermore, the trip interlock rod itself and the number of parts and assembly man-hours required to assemble the interlock rod into the resin case can be reduced compared to the conventional structure, and its assemblability is also simplified, reducing the manufacturing cost of the circuit breaker. Can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a multi-pole circuit breaker according to an embodiment of the present invention, (a) is a schematic diagram showing an assembly structure of a trip interlocking rod with respect to a resin case, and (b) is a tripping interlocking rod. Configuration perspective view

FIG. 2 is a diagram showing a penetrating structure of an interlocking rod with respect to an intermediate case of the resin case in FIG.

3A and 3B are views showing a structure of a bearing portion of an interlocking rod with respect to a side cover of a resin case in FIG. 1, where FIG. 3A is a side view and FIG. 3B is a sectional view of the bearing portion.

4A and 4B are views showing a support structure on the resin case side for the return spring of the interlocking rod in FIG. 1, where FIG. 4A is a sectional view of a bearing portion of the resin case, and FIG. 4B is an arrow view of FIG. A-A sectional view

5 is a diagram showing an opening / closing mechanism of a single-pole circuit breaker for each pole in FIG. 1 and an ON operation state thereof.

FIG. 6 is a diagram showing a trip operation state corresponding to FIG.

[Explanation of symbols]

 1 Resin case 1a Middle partition wall 1b Middle case 1c Side cover 1d Bearing part 1e Through hole 1f Positioning stopper 1g Rib-shaped protrusion 2 Single pole circuit breaker 3 Tripping interlocking rod 3b, 3c Engaging arm 3d Protrusion 3e Return spring 4 fixed Contact 5 Movable contact 6 Operation handle 7 Opening / closing mechanism 8 Overcurrent trip device

Claims (4)

[Claims] 1. An interlocking trip device for a multi-pole circuit breaker comprising a plurality of single-pole circuit breakers equipped with an opening / closing mechanism and an overcurrent trip device for each pole. It is built in a resin case partitioned by a partition wall and has a bifurcated engagement arm attached to connect the switching mechanism and the overcurrent trip device across the circuit breakers of each pole. In a case where the tripping interlocking rod is incorporated in a resin case, the interlocking rod is regarded as one rod and an engaging arm corresponding to each pole is provided on its axis, and a return spring for urging the interlocking rod to a neutral position, Also, an interlocking trip device for a multi-pole circuit breaker is characterized in that the shaft end of the interlocking rod is pivotally supported by a bearing portion formed on a side cover of a resin case. 2. The interlocking trip device according to claim 1,
An interlocking trip device for a multi-pole circuit breaker, characterized in that a trip interlocking rod and a through hole through which an engaging arm projecting from the shaft of the interlocking rod is opened in a partition wall of a resin case. 3. The interlocking trip device according to claim 1,
As a positioning means for holding the tripping interlocking rod at a neutral position against the return spring, a protrusion is provided on the shaft end peripheral surface of the interlocking rod, and a positioning stopper is provided on the bearing portion of the resin case cover facing the protrusion. An interlocking trip device for a multi-pole circuit breaker. 4. The interlocking trip device according to claim 1,
As a torsion coil spring in which a return spring is fitted on the axis of the interlocking rod, a bifurcated engagement arm that protrudes both ends of the coil spring before bending into the resin case with the coil spring bent With the interlocking rod assembled in the resin case, the other end of the coil spring is removed from the engaging arm while the interlocking rod is embedded in the resin case. An interlocking trip device for a multi-pole circuit breaker, characterized in that a rib-shaped projection protruding from the peripheral surface is used to hold the rib.