JP3227327B2 - Circuit breaker - Google Patents

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 circuit breaker having a neutral pole.

[0002]

2. Description of the Related Art Circuit breakers include those that open and close only voltage lines and those that open and close both voltage lines and neutral lines.
As a conventional example for opening and closing both the voltage line and the neutral line, there is one disclosed in Japanese Patent Publication No. 54-2387. This conventional example is a four-pole type circuit breaker used for a three-phase four-wire circuit. The movable switching unit included in this conventional example includes a movable contact on one neutral line side (hereinafter, referred to as a neutral pole) and three movable contacts on a voltage line side (hereinafter, referred to as a voltage pole). It comprises a conductive part attached to one common crossbar, and an opening / closing operation mechanism provided on the voltage pole side. This circuit breaker can open and close four movable contacts simultaneously by operating the handle of the opening and closing operation mechanism.

[0003] On the other hand, there is a three-pole type circuit breaker which is not described in this publication but is used for a three-phase three-wire circuit which opens and closes only a voltage line. The movable switching unit includes a movable contact only on the voltage pole side of the four-pole circuit breaker and an opening / closing operation mechanism. That is, the four-pole type circuit breaker is configured by adding a neutral pole to the three-pole type circuit breaker.

[0004]

However, since the movable contact uses a copper material or a silver contact and the opening / closing operation mechanism has a large number of parts and a complicated structure, the cost of the movable opening / closing unit is low. Is relatively high. Further, since it takes a long time to manufacture the movable opening / closing unit in the manufacturing process, it is necessary to stock both the 3-pole and 4-pole movable opening / closing units in the form of a unit in advance based on demand forecast, and the inventory burden is large.

As a solution to this problem, Japanese Utility Model 3-16
As disclosed in Japanese Patent Publication No. 193, a unitary neutral pole is attached to a three-pole type circuit breaker so as to interlock.
However, this method can be applied only to a large circuit breaker having a relatively large size.

A main object of the present invention is to provide a circuit breaker having a neutral pole which can be applied to a relatively small circuit breaker, is easy to assemble, and has a high reliability. is there.

[0007]

A circuit breaker according to the present invention has a voltage pole and a neutral pole in a housing, and the neutral pole is provided at an end pole adjacent to the voltage pole, and a switching operation is performed on the voltage pole side. In a circuit breaker provided with a mechanism, a first crossbar and a neutral pole rotated by an opening / closing operation mechanism while holding a movable contact of a voltage electrode coaxially connected so as to be integrally rotatable. A crossbar comprising a second crossbar for holding the movable contact of the first and second crossbars, and a connecting groove formed on one of end faces of the first and second crossbars, wherein the first and second crossbars face each other. A projection that fits into the formed connection groove, and a movable portion of the neutral electrode is formed in a unit shape on the projection and is formed to have a U-shaped cross section, and extends in a direction orthogonal to the bottom surface of the housing. Wear with both arms closer to the voltage pole and closer to the outside. When the neutral pole is formed in the unit shape, the second crossbar has one end rotatably held by an arm near the outside of the frame and the other end near the voltage pole side of the frame. Are inserted into notches substantially parallel to the bottom surface of the casing formed on the arms of the first and second crossbars, and the connecting grooves and projections of the connecting means of the first crossbar and the second crossbar are connected to the housing when the circuit breaker is in an open state. It is formed in a direction substantially perpendicular to the bottom surface.

[0008]

The circuit breaker according to the present invention has a voltage pole side unit including a switching operation mechanism and a neutral pole side unit. When one unit is mounted on a housing and then the other is mounted,
A circuit breaker having a neutral pole can be configured only by slidingly connecting the connecting means including the connecting grooves and the protrusions of the first crossbar and the second crossbar. In this connection operation,
When the circuit breaker is in the open state, the connection groove and the protrusion are formed so as to be orthogonal to the bottom surface of the housing, so that the circuit breaker can be more easily performed. Further, even when the two crossbars are connected in a state where the coaxiality is slightly deviated, the second crossbar can be slightly slid in the direction of the connection groove at the connection portion with the first crossbar in the opening and closing operation even when the two crossbars are connected. Even the notch formed in the arm near the voltage pole can slide slightly in the direction of the notch, so that both crossbars can rotate smoothly.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A circuit breaker according to one embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a plan view of a three-phase four-wire four-pole type circuit breaker in which a part of a cover 1 is cut away. A left three pole is a voltage pole, and a right end pole is a neutral pole. If the cover 1 and the base 2 are replaced with three-pole type ones except for the neutral pole on the right end of the circuit breaker in FIG. 1, a three-phase three-wire three-pole type circuit breaker is obtained. 2 and 3 are side cross-sectional views of the voltage pole in the closed state and the open state, respectively, as viewed from AA in FIG. The conductive part and the mechanical part of the circuit breaker according to this embodiment are composed of a cover 1 made of molded insulating material and a base 2.
The voltage pole side and the neutral pole side will be described in the following order.

First, the voltage pole side will be described. The conductive portion of each of the voltage poles includes a fixed contact 4 having a fixed contact 3 and also serving as a power supply terminal, a movable contact 6 having one end of a movable contact 5 and a flexible wire 8 attached to both ends thereof, and a flexible contact. A movable contactor unit comprising a relay terminal 9 to which the other end of the wire 8 is attached; a heater 10 connected to the relay terminal 9;
1 and a heater unit in which the load-side terminals 7 are sequentially connected. When an overcurrent flows, the heater 10 bends the bimetal 12 to automatically open the circuit breaker. The mechanical part on the voltage pole side is mainly configured near the central pole on the voltage pole side, and the movable contact 6 of each of the above-mentioned voltage poles is rotatably held by a cross bar 13 included in this mechanical part. Links 15 and 16 are connected between the rotatably supported handle 14 and the rotatably supported crossbar 13. The link between the link 15 and the link 16 and the handle 14 are connected to each other. An operation spring 17 is stretched between them. The above-mentioned movable contactor unit and this mechanism part integrally form a voltage pole side mechanism unit.

The opening / closing operation on the voltage electrode side configured as described above will be described. In FIG. 2, the connecting portion between the link 15 and the link 16 is deflected rightward by the action of the spring 17 by a stopper (not shown) and stopped, and the movable contact 6 is
8, the movable contact 5 and the fixed contact 3 are in contact with each other in a clockwise direction. When the handle 14 is turned counterclockwise from the state shown in FIG. 2, the operation force of the spring 17 acts so that the link between the link 15 and the link 16 moves to the left. Rotating clockwise around the center, the crossbar 13 is rotated counterclockwise through the link 16 to obtain the open state shown in FIG. In this state, the movable contact 5 is separated from the fixed contact 3. Note that the closing operation is the reverse. The two contact points are separated from each other by a trip mechanism that rotates the crossbar 13 in a counterclockwise direction when the bimetal 12 is bent, in addition to the operation of the handle 14. .

Next, the neutral pole will be described. Figures 4 and 5
FIG. 2 is a side sectional view of the neutral pole side in a closed circuit state and an open circuit state, respectively, as viewed from BB in FIG. 1. In these figures, the cover 1 is omitted. The conductive part and the mechanism part of the neutral electrode are housed in the cover 1 and the right end of the base 2. The conductive portion includes a fixed contact 21 having a fixed contact 20 and also serving as a power supply terminal, a movable contact 23 having a movable contact 22 and rotatably supported by a fixed shaft 33 of a frame 26 described later, and a movable contact. It comprises a flexible wire 25 and a load-side terminal 24 which are sequentially connected from the contact 23. The mechanism part of the neutral pole is formed inside a frame 26 formed by bending the cross section into a U-shape, and includes a crossbar 30, a fixed shaft 27 and a movable contact 2.
3 and the link 30 and the link 30 and the arm 30 of the crossbar 30
a and a spring 32 that biases the movable contact 23 in the clockwise direction to contact the movable contact 22 with the fixed contact 20. The mechanism part and the conductive part except the fixed contact 21 form a neutral pole side mechanism unit as one body. The link 28, the link 29, the link 31 and the like, when the circuit breaker is opened and closed, the contact of the neutral electrode comes in contact before the contact of the voltage electrode and opens afterwards, thereby generating an abnormal voltage. Although it is provided for prevention, it is not a main part of the present invention, so that the detailed description is omitted.

The opening / closing operation of the neutral pole configured as described above will be described. FIG. 4 shows that the link 28 and the link 29 are substantially in a straight line due to the angle of the crossbar 30 linked to and interlocked with the crossbar 13 in the closed state, and the movable contact 22 and the fixed contact 20 are in contact. When the handle 14 is operated in the state shown in FIG. 4, the crossbar 13 rotates, and the crossbar 30 interlocking with the rotation rotates counterclockwise, and the link 28 moves the fixed shaft 27 via the link 31. Rotating clockwise around the center, the movable contact 23 rotates counterclockwise through the link 29, the movable contact 22 is separated from the fixed contact 20, and the circuit is in the open state shown in FIG. The closing action is the reverse.

Next, the connection between the crossbar 13 on the electrode side and the crossbar 30 on the neutral pole side will be described with reference to FIG. The crossbar 30 is rotatably supported at one end 30b thereof by a shaft hole formed in one arm 26a of the frame 26, and is coaxially connected at the other end to the crossbar 13 on the voltage pole side. A groove 13b is formed outside the wall 13a at the end of the crossbar 13. On the other hand, the other part of the crossbar 30 is provided with a projection 30c fitted into the groove 13b and an engagement groove 30d fitted into the wall 13a when fitted and connected.
On the other arm 26b of the frame 26, a "U" -shaped notch 26c having a width slightly larger than the diameter of the crossbar 30 is formed with the load side as an opening, and the crossbar 30 is inserted therethrough.

When assembling the circuit breaker according to this embodiment, first, the fixed contacts on the voltage pole side and the neutral pole side and the heater unit are attached to the base 2, then the voltage pole side mechanism unit and the neutral pole The side mechanism units are sequentially attached to the base 2. When the neutral pole side mechanism unit is incorporated, the protrusion 30c of the crossbar 30 is fitted into the groove 13b of the crossbar 13 and moved so as to slide, and at the final stage, the crossbar 30 is attached to the end of the wall 13a of the crossbar 13. The engagement groove 30d is fitted. FIG. 7 is a view for explaining the positional relationship between the crossbar 13 and the movable contact 6 in the open state. The groove 13b of the crossbar 13 is substantially perpendicular to the bottom surface of the base 2,
In addition, since the opening is provided upward, the work of fitting the crossbar 30 and the protrusion 30c is easy. The circuit breaker of this embodiment having the above-described structure can be easily assembled by 1) incorporating the voltage pole side mechanism unit and then fitting the neutral pole side mechanism unit to both crossbars. it can. 2) The rotation of the crossbar 13 is transmitted to the crossbar 30 because the protrusion 30c of the crossbar 30 fits into the groove 13b of the crossbar 13. 3) When both crossbars are connected, the wall 13a of the crossbar 13 and the engagement groove 30d of the crossbar 30 are fitted to each other, so that even if an unexpected force is applied, the crossbar 13 does not separate in the axial direction. 4) The crossbar 30 is pivotally supported by both arms of the frame 26, and
3 is connected to the crossbar 1 when the mounting positions of the voltage pole side and the neutral pole side mechanism units are slightly shifted.
Since the 3 and the crossbar 30 are not coaxial, even this slight displacement does not allow smooth rotation and causes malfunction. On the other hand, according to this embodiment, the crossbar 3
One end of 0 is pivotally supported by the arm 26a of the frame 26, but the other end is not completely supported, so that such an operation failure does not occur. That is, the crossbar 30 is automatically shifted along the direction of the groove 13b of the crossbar 13 with respect to the mounting displacement in the vertical direction with respect to the bottom surface of the base 2. However, any further displacement that may occur during the opening / closing operation is limited by the width of the notch 26c of the frame 26, and the fitting between the wall 13a and the engaging groove 30d does not come off. In addition, with respect to the mounting displacement in the horizontal direction with respect to the bottom surface of the base 2, the notch 26
The crossbar 30 is automatically shifted in the notch direction c. As described above, even if the mounting position is slightly shifted, the rotation of the crossbar 30 is not restricted, and the assembly is simple and high reliability can be secured. 5) The portion of the other arm 26b of the frame 26 through which the crossbar 30 is inserted is cut out, so that the neutral pole side mechanism unit can be easily assembled. That is, only the movable portion of the neutral pole side mechanism unit including the crossbar 30 is assembled, the crossbar 30 is pivotally supported at one end 30b to one arm 26a of the frame 26, and the intermediate portion near the other end is connected to the other end. The neutral pole side mechanism unit can be assembled simply by fitting the fixed shafts 27 and 33 into the notches of the arm 26b, and there is no need to perform the mounting work of a large number of parts inside the frame 26.

In this embodiment, the grooves are formed on the crossbar 13 side and the protrusions are formed on the crossbar 30 side.
Further, the engagement means for preventing the detachment in the axial direction includes the crossbar 3.
0, a wall is formed, and an engaging groove for engaging this wall is
3 may be provided on the bottom surface side of the base 2. Further, in the present embodiment, the voltage pole side mechanism unit and the neutral pole side mechanism unit are sequentially mounted, but may be reversed. For this reason, the engagement means for preventing the detachment in the axial direction is provided by providing an engagement groove of the crossbar 30 on the bottom surface side of the base 2 or by providing this engagement groove on the upper portion of the crossbar 13 and engaging with the wall. The structure provided on the 30 side is adopted.

[0017]

As described above, according to the present invention, a circuit breaker having a neutral pole is assembled into a neutral pole unit and a voltage pole side unit of a circuit breaker having no neutral pole. Since the unit can be assembled simply by inserting and connecting the two crossbars, the stock load can be reduced, and the connecting means has a play, so that an easy-to-assemble and highly reliable circuit breaker can be obtained.

[0018]

[Brief description of the drawings]

FIG. 1 is a plan view of a circuit breaker according to the present invention, in which a part of a cover is cut away.

FIG. 2 is a side sectional view on the voltage pole side in a closed state viewed from AA in FIG. 1;

FIG. 3 is a diagram of an open circuit state in FIG. 2;

FIG. 4 is a side sectional view of the neutral pole side in a closed state viewed from BB in FIG. 1;

FIG. 5 is a diagram showing an open state of FIG. 4;

FIG. 6 is a diagram illustrating a state in which a crossbar on the voltage pole side and a crossbar on the neutral pole side are connected.

FIG. 7 is a diagram illustrating a positional relationship between a crossbar and a movable contact in an open state.

[Explanation of symbols]

 Reference Signs List 1 cover 2 base 4 fixed contact 6 movable contact 13 crossbar 13a wall 13b groove 14 handle 15, 16 link 17 operating spring 18 spring 21 fixed contact 23 movable contact 26 frame 26c U-shaped cutout 28 , 29, 31 Link 30 Crossbar 30c Protrusion 30d Engagement groove 32 Spring

Claims (1)

(57) [Claims] A voltage pole and a neutral pole are provided in the housing (1, 2), the neutral pole is provided at an end pole adjacent to the voltage pole, and an opening / closing operation mechanism is provided on the voltage pole side. A first crossbar (13), which holds a movable contact (6) of the voltage electrode, which is coaxially connected so as to be integrally rotatable, and is rotated by the opening / closing operation mechanism. And a second crossbar (3) holding the neutral movable contact (23).
0), the first crossbar (13) and the second crossbar (30).
And a projection (30c) that fits into the connection groove (13b) formed on one of the end faces of the two crossbars and the connection groove (13b) formed on the other.
The two arms (26a, 26a, 26a, 26a) on which the movable part of the neutral pole is formed in a unit shape and the section is formed so as to have a U-shape,
b) has a frame (26) mounted so as to be closer to the voltage pole and to the outer side, and the second pole is formed when the neutral pole is configured in the unit shape.
The crossbar (30) has one end rotatably held by the outer arm (26a) of the frame (26) and the other end near the voltage pole side arm (26) of the frame (26).
b) a notch (2) substantially parallel to the bottom surface of the housing formed in
6c), the first crossbar (13) and the second crossbar (3)
0) the connection groove (13b) and the projection (30) of the connection means;
c) is a circuit breaker formed in a direction substantially orthogonal to the bottom surface of the housing (2) when the circuit breaker is in an open circuit state.