JP2519599B2 - Circuit breaker - Google Patents

Description

TECHNICAL FIELD The present invention relates to a circuit breaker, and more particularly to a circuit breaker having both a circuit breaker function and an electromagnetic switching function.

[Prior Art] Generally, a circuit breaker is intended to protect an electric circuit and a system device against an overload current or a short circuit current. When the frequency of switching the load is high, an electromagnetic switch connected in series with the circuit breaker is provided, and the load is switched by the electromagnetic switch having a long switching endurance performance.

Conventionally, there are the following three types of prior art in which the functions of the circuit breaker and the electromagnetic switch are integrated.

The first type is disclosed, for example, in JP-A-52-132382. In this type, the function of the circuit breaker and the function of the electromagnetic switch are integrally combined, and the contacts are provided separately for short circuit break and for load switch. Although this type has excellent performance, it is not economical because the device is large.

The second type is disclosed, for example, in Japanese Examined Patent Publication No. 39-5573. This type mechanically connects the electromagnet for operation and the contactor to open and close the load,
It has a structure that disconnects this function when an overcurrent occurs. That is, this connection mechanism is of a trip-free type, and when the overcurrent trip device operates, the operation electromagnet opens and the connection is cut off. Therefore, high-speed cutoff can be performed. However, this trip-free system has a complicated mechanism, and since the trip-free mechanism is simultaneously operated at the time of opening / closing operation, it is not possible to obtain a good opening / closing durability performance.

Further, as a third type, for example, Japanese Patent Publication No. 63-3609.
Some are disclosed in Japanese Patent Publication No. 7. This type has an operation electromagnet, a short-circuit protection electromagnet, and an overcurrent trip device, and both the operation electromagnet and the short-circuit protection electromagnet act directly on the connecting means of the contact device. This type has excellent open / close durability. When a large current is cut off, the short-circuit protection electromagnet directly opens the contact, and at the same time, the overcurrent trip device operates to cut off the excitation current of the operation electromagnet and deactivate it.

[Problems to be Solved by the Invention] However, in the circuit breaker of the third type, when breaking a large current, the contacts are first opened by the operation of the short-circuiting electromagnet, and the current is once cut off.

When the current is cut off, the protection electromagnet will be de-energized during a short circuit,
It tries to re-energize. However, a latch mechanism for preventing the re-energization is provided to prevent the re-energization. However, the latch mechanism according to this example does not have an automatic reset mechanism, and it was necessary to artificially perform the reset operation of the latch mechanism in order to reclose the circuit.

Therefore, an object of the present invention is to prevent the circuit from being shut off immediately when an excessive current such as a short-circuit current is generated in the main current path, and to prevent the circuit from closing immediately after the circuit is shut off. It is an object of the present invention to provide a circuit breaker capable of continuously maintaining a circuit cutoff state for prevention and automatically returning to a state where the circuit can be reclosed.

[Means for Solving the Problem] In order to make it easy to understand the correspondence between the components of the present invention and the components of the illustrated embodiment, reference numerals in the drawings are given in parentheses. Reference numbers are provided for ease of understanding only and are not intended to be limiting to the illustrated embodiments.

A circuit breaker according to the present invention comprises a fixed contact (10),
Movable contact means (9), first connecting means (17), first
A spring means (11), a current-operated electromagnet (30), a transmission means (18), an open state maintaining means (110, 112, 113), and an urging force cutoff means.

The fixed contact (10) is provided in the middle of a main current path connecting the power source side circuit terminal (16) and the load side circuit terminal (43). The movable contact means (9) opens and closes the main current path by contacting and opening the fixed contact. The first connecting means (17) is connected to the movable contact means and is displaceable. The first spring means (11) urges the movable contact means to contact the fixed contact.

The current-operated electromagnet (30) is excited and operates in response to the occurrence of an excessive current of a predetermined value or more in the main current path.
The transmission means (18) transmits the movement of the current-operated electromagnet to the first connecting means, thereby separating the movable contact means from the fixed contact against the biasing force of the first spring means.

The separated state maintaining means (110, 112, 113) fixes the position of the transmission means by balancing the biasing force of the first spring means acting on the transmission means and the biasing force acting in the opposite direction to the movable contactor. The open state between the means and the fixed contact is maintained.

The biasing force cut-off means moves the movable contactor means against the biasing force of the first spring means after the transmission of the force to the movable contactor means by the transmitting means in accordance with the generation of the excessive current, and thereby, The biasing force of the first spring means acting on the separated state maintaining means is cut off.

In one embodiment, the current operated electromagnet is a plunger type. The transmission means is rotatably provided, and one end thereof is rotatably provided with a first lever (110) which comes into contact with the plunger (31) of the current-operated electromagnet, and one end of which is the first connecting means (17). ) Contacting the second lever (113),
A link member (112) connecting the other end of the first lever and the other end of the second lever is provided.

In one embodiment, the biasing force cutoff means comprises a voltage operated electromagnet (60) and a second connecting means (74). The voltage-operated electromagnet (60) includes a fixed part (61), a movable part (62) that moves in response to an opening / closing command of a main current path, and a spring (64) that biases the movable part so that the fixed part moves away from it. Have and. The second connecting means (74) transmits the movement of the movable portion (62) urged by the spring to the first connecting means (17), thereby causing the movable contactor means to oppose the urging force of the first spring means. To move.

In one embodiment, the urging force cut-off means is an overcurrent responsive means (46, 50, 54, 10) for detecting and responding to an overcurrent.
2,103) and the movement of the overcurrent responsive means to the first connecting means (1
7), thereby moving the movable contact means against the biasing force of the first spring means (87, 90, 91, 92,
93,97,99) and.

In one embodiment, the circuit breaker further includes a second bias to bias the transmission means (18) back to its original position.
Spring means (115) are provided.

[Operation] The current-operated electromagnet (30) is excited and operates in response to the occurrence of an excessive current of a predetermined value or more in the main current path.
In one embodiment, the current-operated electromagnet is a plunger type, in which case it is excited in response to the generation of an excessive current to move the plunger (31) in a predetermined direction. The transmission means (18) is
The movement of the plunger (31) is transmitted to the first connecting means (17) to move the first connecting means (17) downward. Since the first connecting means (17) is connected to the movable contactor means (9), the movable contactor means (9) moves to the fixed contact (10) as the first connecting means (17) moves downward. ) Away from. Thus, when an overcurrent occurs in the main current path, the circuit is immediately shut off. The first spring means (11) biases the movable contact means (9) so as to contact the fixed contact (10). Second spring means (115) employed in one embodiment
Urges the transmission means (18) to return to its original position.

Since the excitation of the current-operated electromagnet is released as the circuit is cut off, the plunger (31) moves upward by the urging force of the spring (34). At this time, what if the transmission means (18)
When is returned to its original position by the urging force of the second spring means (115), the engagement state between the transmission means (18) and the first connecting means (17) is released, so that the movable contact means ( 9) moves upward due to the urging force of the first spring means (11) and comes into contact with the fixed contact (10). In order to prevent such energization immediately after the circuit breaks, the circuit breaker of the present invention has a biasing force of the first spring means (11) acting on the transmitting means (18) and a biasing force acting in a direction opposite thereto. There is provided a separated state maintaining means for fixing the position of the transmission means (18) and maintaining the separated state between the movable contact means (9) and the fixed contact (10) by balancing the forces.

A more specific description will be given based on the embodiment shown in FIG. 13B. FIG. 13B shows the state immediately after the circuit is cut off. The first lever (110) tends to rotate counterclockwise by the biasing force of the spring (115). In other words, the connecting shaft between the first lever (110) and the link member (112) tends to rotate counterclockwise about the shaft (111).
As is clear from the figure, such counterclockwise rotation is only possible when the connecting shaft between the link member (112) and the second lever (113) moves counterclockwise about the shaft (114). It will be possible. However, the second lever (11
One end of 3) is pushed up by the first connecting means (17) biased by the first spring means (11) and is about to rotate clockwise. In other words, the first spring means (11) tries to rotate the connecting shaft of the link member (112) and the second lever (113) clockwise about the shaft (114). A first spring means (1) for rotating the connecting shaft of the link member (112) and the second lever (113) clockwise.
The urging force of 1) is balanced with the urging force of the second spring means (115) for rotating the same connecting shaft counterclockwise or the reaction force acting on the first lever (110) from the frame,
As a result, the position of the transmission means (18) is fixed. Thus, the separated state between the movable contactor means (9) and the fixed contact (10) is maintained.

In the circuit breaker of the present invention, the movable contact means is provided with the first spring means (11) after the force is transmitted to the movable contact means (9) by the transmission means (18) due to the generation of the excessive current. There is provided an urging force cutoff means for moving the urging force of the first spring means (11) acting on the transmission means (18) by moving it against the urging force. An example of the biasing force cut-off means is shown in FIG. 2, and other examples are shown in FIGS. 5 and 6.
It is illustrated in the figure.

An example of the biasing force cutoff means will be described with reference to FIG. The voltage-operated electromagnet (60) includes a fixed part (61), a movable part (62) that moves according to an opening / closing command of a main current path,
And a spring (64) for urging the movable portion (62) away from the fixed portion (61). When the circuit is cut off, the voltage-operated electromagnet (60) is in a non-excited state, so that the movable part (62) moves away from the fixed part (61) and the second
The connecting means (74) is rotated clockwise in the figure. First
See Figure 13B. The second connecting means (74) pushes down the first connecting means (17) against the biasing force of the first spring means (11). As a result, the separated state maintaining means (110, 112, 11
Since the biasing force of the first spring means (11) acting on 3) is cut off, the transmission means (18) returns to the original position shown in FIG.

Please refer to FIG. 5 and FIG. 6 showing another example of the biasing force cut-off means. The overcurrent responsive means rotates the member (102) clockwise when an excessive current flows in the main current path. As a result, the member (102) rotates the member (99) shown in FIG. 6 in the clockwise direction, and finally the member (87).
Is rotated clockwise. The member (87) moves the second connecting means (74) downward. As a result, the first connecting means (17) moves downward, and the biasing force of the first spring means (11) acting on the separated state maintaining means is cut off.

[Embodiment] FIG. 1 is an external perspective view of a circuit breaker having a three-pole type overload short-circuit protection function according to an embodiment of the present invention.
The circuit breaker housing is composed of a base 1, an operating mechanism unit housing 3, a trip unit housing 4, and three opening / closing breaker unit housings 2 independent for each pole. Further, FIG. 15 is a circuit configuration block diagram showing a schematic configuration of the circuit breaker. First
Referring to Fig.15, the circuit breaker has three independent main current paths, and disconnection contact DS, main contact S, electromagnet ST for forced opening at short circuit, and current detection in the middle of each electric path. Current transformer CT
And a zero-phase current transformer ZCT is provided. Further, three opening / closing means are provided as contact opening / closing means for opening / closing the main contact S. The first opening / closing means is means for opening / closing the main contact S using the opening / closing electromagnet 60. The second opening means disconnects the main contact S by a spring releasing mechanism 75b which operates by receiving a detection signal from the current detecting current transformer CT or the zero-phase current transformer ZCT provided in the main current path. It is a thing. The third opening means is a means for disconnecting the main contact S by the operation of the electromagnet ST for forced opening during a short circuit provided in the main current path. The structure of the circuit breaker having such a circuit configuration and mechanism will be described below.

2 is a central side sectional view of the circuit breaker shown in FIG. 1 in a closed state, and FIG. 3 is a plan view from a direction along a cutting line XX of FIG. Referring to both figures, the circuit breaker comprises a hollow base 1 made of a molded insulating material, an opening / closing breaker unit housing 2 made of a molded insulating material inserted from the bottom of the base 1 and independent for each pole, and a base. 1
Operating unit housing 3 made of an insulating material formed on one side of the upper part of the base 1, and a trip unit housing 4 made of a molded insulating material formed on the other side of the upper part of the base 1.
And are attached.

The switchgear unit housing 2 has an elongated shape,
A current path is formed from the power source side terminal conductor 16 arranged at one end thereof to the first fixed conductor 12, the main contact portion 5 and the second fixed conductor 14 through the disconnecting portion 13. Arc extinguishing devices 7, 7 are arranged on both sides of the main contact portion 5. The main contact portion 5 is
A bridge type having a pair of fixed contacts 10 and 10 provided on the first fixed conductor 12 and the second fixed conductor 14 and movable contacts 8 and 8 at positions contacting the fixed contacts 10 and 10. The movable contactor 9, a contactor spring 11 for supporting the movable contactor 9 from the lower surface and constantly pressing the movable contact 8 against the fixed contact, and an opening / closing operation lever 17 extending in the vertical direction and connected to the movable contactor 17
With. The opening / closing operation of the main contact part 5 is performed by the opening / closing operation lever 17
By pressing down, the fixed contacts 10 and 10 and the movable contact 8,
8 is opened, and the returning operation is performed by the fixed contact 10 and the movable contact 8 coming into contact with each other by the restoring force of the contactor spring 11.

One end of the first fixed conductor 12 having one fixed contact 10 is extended to an upper portion of the arc extinguishing device 7 to form an arc horn, and the other end thereof is extended to the disconnecting portion 13. The second fixed conductor 14 having the other fixed contact 10 has one end extended to the upper part of the arc extinguishing device 7 to form an arc horn,
The other end is folded back and extended along the upper portion of the housing 2 so as to be exposed in the groove portion of the trip unit housing 4 through the through hole of the base 1.

A link mechanism 18 for forcibly opening contacts during a short circuit is provided near the top of the main contact 5 in the opening / closing breaker unit housing 2. This will be described later.

Further, the arc runner 15 provided along the bottom wall of the opening / closing breaker unit housing 2 has an arc runner portion formed by extending to the fixed contacts 10 and 10 side of the first fixed conductor 12 and the second fixed conductor 14. Correspondingly, it is provided under the arc extinguishing devices 7, 7.

The trip unit housing 4 includes an electromagnet 30 for forced opening at short circuit, a zero-phase current transformer 40, a current transformer 41 for current detection, and a load-side terminal conductor 43, which are connected in series and are connected to the main current path. Make up.

The short-circuit forced opening electromagnet 30 is a plunger type electromagnet including a fixed iron core 32, a movable iron core 33 corresponding thereto, a return spring 34, a magnetic yoke 35, and an exciting coil 36. A projecting rod 31 is integrally attached to the movable iron core 33. The tip of the protruding bar 31 penetrates through holes provided in the trip unit housing 4, the base 1 and the opening / closing cutoff unit housing 2, and a link mechanism for forced opening at the time of short circuit.
It is in contact with 18 first levers 110. The input end of the exciting coil 36 is connected to the second fixed conductor 14 exposed at the upper part of the switching breaker unit housing 2 by a screw 24, and the output conductor 39 is provided as necessary and is used for one of the three poles.
A current transformer for current detection through the through holes of two zero-phase current transformers 40.
It is wound as a primary coil on one piece of the iron core 42 of 41.

The lead-out end of the primary coil of the current detecting current transformer 41 is connected to one end of the load-side terminal conductor 43. A secondary side coil 44 is wound around the other side of the iron core 42 of the current detecting current transformer 41, and a lead wire of the secondary side coil is connected as an input of an electronic overcurrent relay 45 arranged above the secondary side coil 44. It

With the above configuration, a main current path from the power supply side terminal conductor 16 to the load side terminal conductor 43 is formed.

Next, the configuration of the three separating means of the main contact 5 will be described.

First, the opening / closing operation electromagnet 60 is used as the first contact opening means.
The configuration using will be described. Referring to FIGS. 2 to 4, the opening / closing operation electromagnet 60 is arranged in the operation mechanism unit housing 3 together with the operation control mechanism 75. The electromagnet 60 for opening / closing operations includes an E-shaped fixed iron core 61, a corresponding E-shaped movable iron core 62 corresponding thereto, an exciting coil 63 for winding the central leg of each iron core, and a suction release spring 64.
It is composed of The fixed iron core 61 of the opening / closing operation electromagnet 60 is fixedly supported together with the fixed frame 65 by the leaf spring 66 inserted in the through hole 61a provided in the fixed iron core 61 on the end cover 3a of the operation mechanism unit housing. The movable iron core 62 is movably attached to the fixed frame 65 via a suction release spring 64 by a spring installation plate 69 integrally mounted with the movable iron core 62. The suction / release spring 64 constantly urges the movable iron core 62 in a direction away from the fixed iron core 61. The movable iron core 62 is formed with a movable iron core operating pin 73 which penetrates the movable iron core 62 and moves integrally with the movable iron core 62. Further, an electromagnet operating lever 71 that engages with the movable iron core operating pin 73 is attached to one end of the fixed frame 65 so as to be rotatable around a shaft 72. A crossbar 74 is attached to one end of the electromagnet operating lever 71. Crossbar 74
Is composed of an integrally formed body that simultaneously abuts the heads of the opening / closing operation levers 17, 17, 17 protruding from the three opening / closing shutoff unit housings 2, 2, 2 arranged in parallel inside the base 1. .

Further, the second contact opening means is shown in FIGS.
Description will be made with reference to FIGS. 5, 5 and 6. FIG. 5 is an enlarged plan view of an essential part near the release electromagnet 46 in FIG. FIG. 6 is a sectional structural view taken along the line Y- in FIG. The second contact opening means is a three-pole interlocking crossbar from one end of the secondary coil 44 of the current detecting current transformer 41 through the electronic overcurrent relay 45 and the release type electromagnet 46 and the operation control mechanism 75. It is composed of up to 74 devices. Referring to FIG. 5, the release electromagnet 46 includes a U-shaped frame 47 made of a magnetic material, a permanent magnet 48 arranged in the U-shaped frame, and a tripping member for winding one end of the U-shaped frame 47. The coil 49, an armature 50, a support member 51 that rotatably supports the armature 50, and a trip spring 52 are included. In the release electromagnet 46, the armature 50 is attracted and held by the leg portion of the U-shaped frame 47 against the acting force of the trip spring 52 by the magnetic flux provided by the permanent magnet 48 at all times. When an output signal is input to the trip coil 49 from the electronic overcurrent relay 45 in this state, a magnetic flux is generated in a direction of canceling the magnetic flux of the permanent magnet 48, and the armature 50 is dissociated from the leg portion of the U-shaped frame 47. To do. One end of the armature 50 is in contact with a trip transmission plate 54 that transmits the dissociation motion of the armature 50, and the other end of the trip transmission plate 5 is in contact with one end of the response transmission plate 103. The other end of the response transmission plate 103 is in contact with one end of the overload response trip operation plate 102. The overload-responsive trip actuating plate 102 rotates about the shaft 101. The other end of the overload-responsive trip actuating plate 102 corresponds to the secondary hook 99 of the operation control mechanism 75 shown in FIG. The transmission mechanism shown in FIG. 5 converts an overcurrent detection signal generated in the main current path into a mechanical signal.

Next, the structure of the operation control mechanism 75 will be described with reference to FIG. The operation control mechanism 75 is roughly divided into a handle mechanism portion 75a operated by a control handle 79,
Spring release mechanism part 75b for mechanically opening and closing the main contact
It is divided into The handle mechanism 75a is a control handle 79
And the camshaft attached to this control handle 79
77 and an eccentric cam 76 connected to the cam shaft 77, and a slide plate 84 connected to the eccentric cam 76 and performing a sliding motion. The control handle 79 is rotatably supported, and has "AUTO", "TRIP", "OFF", "RESET",
It has six switching positions of "TEST" and "ISOL". A cam groove 76a shown in FIGS. 7B, 9B and 11B is formed on the lower surface of the eccentric cam 76, and the tip of the slide plate sliding pin 83 is inserted into this cam groove. The slide plate sliding pin 83 passes through a linear guide hole provided in the fixed frame 80 and is crimped to one end of the slide plate 84. A part of the slide plate 84 is an ear portion bent in an inverted U shape.
It has 84a. With such a structure, when the control handle 79 is rotated, the rotational movement is converted into the linear movement of the slide plate 84 by the action of the eccentric cam 76.

The spring release mechanism 75b has the secondary hooks 9 in the order of engagement.
9, a primary hook 97, a release lever 93, a link 92, a link 90 and a crossbar control lever 87. The bent piece 99a of the secondary hook 99 is provided at a position corresponding to one end of the overload response trip actuation plate 102, and receives the turning operation of the overload response trip actuation plate 102. The tip of the crossbar control lever 87 is the head 74 of the crossbar 74 for interlocking with three poles.
is in contact with a.

The secondary hook 99 is rotatably supported by a shaft 100, and has one end releasably abuttingly engaged with an upper end portion of the primary hook 97 and a bending piece 99a provided at the other end. The primary hook 97 is rotatably supported by a shaft 98, and a clockwise rotating force is applied by a spring. A hooking pin 97a is attached to the center of the primary hook 97 and is movable along the elongated hole. The release lever 93 is a shaft whose one end is fixed to the fixed frame 80.
It is rotatably supported by 96, and the claw portion 93a at the other end is the primary hook 9
The latching pin 97a of 7 is releasably engaged. A link 92 whose one end is rotatably connected by a shaft 94 is connected to the upper end of the releasable lever 93. The other end of the link 92 is connected to the link 90 via the toggle shaft 91, and
One end of 90 is connected to one end of a crossbar control lever 87 rotatably supported by a shaft 88 via a shaft 89. The two links 90, 92, the toggle shaft 91 between them, and the expansion spring 95 connected between the toggle shaft 91 and the top of the opening / closing control lever 86 constitute a toggle link mechanism. The lower end of the opening / closing control lever 86 is a fixed frame 80.
It is provided so as to be rotatable around the fixed bar 118 as a center.

In the opening / closing control lever 86, a pin 84b provided at a tip of an ear portion 84a of a slide plate 84 is slidably inserted into a groove portion 86a provided on upper portions of both side surfaces thereof. As a result, the spring releasing mechanism 75b and the handle operating mechanism 75a are connected. This operation control mechanism 75 is a mechanism for operating the three-pole interlocking crossbar 74 by opening and closing the crossbar control lever 87 to open and close the main contact of the main current path, and two command inputs as its operation command system. There is a lineage. One is a system in which the spring releasing mechanism 75b is operated via the handle control mechanism 75a by operating the handle 79. As another system, after the abnormal signal detected by the current detecting current transformer 41 is converted into a mechanical signal by the release type electromagnet 46, the secondary hook 99 is operated via the overload responsive trip operating plate 102. It is a system.

Further, the third contact opening means will be described with reference to FIG. The protruding rod 31 of the electromagnet 30 for forced short circuit opening at short circuit arranged in series in the main current path comes into contact with the first lever 110 of the link mechanism for forced short circuit opening at short circuit provided inside the switching breaker unit housing 2. ing. The first lever 110 is the rotating shaft 11
The central portion is rotatably supported by 1. The other end of the first lever 110 is connected to the link material 112,
A second lever 113 is connected to the other end of 112. The second lever 113 has a substantially L-shape, and its central portion has a shaft 1
It is rotatably supported by 14. This first lever
110, link member 112 and second lever 113 constitute a so-called dead center link mechanism. At one end of the first lever 110, the protruding portion of the electromagnet 30 for forced opening during a constant short circuit is provided.
A return spring 115 for urging the side to push back 31 is provided. Further, the tip portion of the second lever 113 is inserted into the hollow portion formed in the upper portion of the opening / closing operation lever 17 of the main contact. The operation of the electromagnet 30 for forced opening during short circuit is performed by operating the protruding portion 31 to move the opening / closing operation lever 17 via the link mechanism 18 for forced opening during short circuit, so that the fixed contact 10 and the movable contact 8 are moved. Open between them and cut off the main current path.

Next, the contact opening / closing operation of the circuit breaker according to the present invention will be described.

First, the contact opening / closing operation using the opening / closing operation electromagnet 60 as the first opening / closing means will be described with reference to FIG.
The opening / closing electromagnet 60 is turned on outside the circuit breaker.
It operates according to the open / close command from the / OFF switch. Excitation coil of electromagnet 60 for opening / closing operation in response to a signal from the outside
When the excitation of 63 is cut off, the movable iron core 62 moves apart from the fixed iron core 61 by the restoring force of the suction / release spring 64. In response to this, the movable iron core operating pin 73 provided on the movable iron core 62 rotates the electromagnet operating lever 71 clockwise about the shaft 72. Then, the crossbar 74 opens and closes the opening / closing operation lever 17
Is pushed downward, and accordingly, the movable contact 8 and the fixed contact 10 of the movable contactor 9 are opened. This breaks the circuit.

In the returning operation, when the exciting coil 63 is energized again, the movable iron core 62 is attracted to the fixed iron core 61, and along with this, the electromagnet operating lever 71, the culobar 74 and the opening / closing operating lever 17 are moved.
Returns to its original position.

Next, regarding the breaking operation of the main contact of the spring releasing mechanism portion which is the second opening means, FIG. 2, FIG. 5, FIG. 7A, and FIG. 7B,
8A, 8B, 9A, 9B, 10A, 10B,
This will be described with reference to FIGS. 11A, 11B, 12A and 12B. Here, FIGS. 7A, 9A, and 11A are plan views of the control handle, and FIGS. 7B, 9B, and 11B.
The figure is a plan view showing the positional relationship between the eccentric cam and the slide plate 84. Also, FIGS. 8A, 10A and 12A are cross-sectional structural views of the handle control mechanism portion in each operating state. 8B, 10B and 12B are cross-sectional structural views of the spring release mechanism portion 75b corresponding to the handle control mechanism.

First, referring to FIGS. 7A to 8B, when the main current path of the circuit breaker is closed, the control handle 79 is at the “AUTO” or “TEST” position, and the spring release mechanism part
75b, the claw portion 93a of the releasable lever 93 engages with the latch pin 97a of the primary hook 97, and the upper end portion of the primary hook 97 and the secondary hook 9
One end of 9 is engaged. Two toggle links 9
The toggle shaft 91 connecting the 0 and 92 is pulled by the upper end of the opening / closing control lever 86 and the expansion spring 95.
The upper part of 92 is locked by the shaft 96. Therefore, the toggle links 90 and 92 are extended almost in a straight line, the crossbar control lever 87 is pushed down as a unit, and the side contacting the 3-pole interlocking crossbar 74 is pushed up to raise the crossbar.
It is separated from the interlocking pin 74a of 74.

Now, when the control handle 79 is in the "AUTO" position and the main contacts 8 and 10 are in the "ON" state, an overload current flows in the main current path, and the output signal of the electronic overcurrent relay 45 is output. When the release type electromagnet 46 operates upon receiving, the armature 50 is opened, the trip transmission plate 54 and the overload response transmission plate 103 are pressed and slid, and the overload response trip actuation plate 102 is rotated. Bending piece 99a formed at the end of the secondary hook 99
Press to move.

Referring to FIG. 10B, when the secondary hook 99 rotates clockwise about the shaft 100 as a fulcrum, the primary hook 97 disengaged from the secondary hook 99 rotates clockwise about the shaft 98 as a fulcrum. Then, the latch pin 97a and the releasable lever 93 are disengaged. The releasable lever 93 rotates counterclockwise about a shaft 96 as a fulcrum to bend the toggle links 90 and 92 and pull up one end of the crossbar control lever 87. Therefore, the crossbar control lever 87 rotates clockwise about the shaft 88 as a fulcrum to push down the interlocking pin 74a of the crossbar 74. When the crossbar 74 is pushed down, the operation levers 17, 17, 17 of the respective poles that are in contact with the crossbar 74 are pushed down, and the main contacts are opened,
It will be in the "off" state. At this time, when the opening / closing control lever 86 is rotated, the slide plate 84 that engages with the bent ear portion 86a is slid to rotate the eccentric cam 76 and the control handle 79, and the control handle 79 is set to “TRIP” Rotated to the indicated position (9A
(See Figures, Figures 9B and 10A).

Further, referring to FIGS. 11A to 12B, in order to return from the “TRIP” state to the openable / closable state, the opening / closing control is performed by forcibly rotating the control handle 79 to the “RESET” position. The lever 86 rotates clockwise, and the pin 86b attached to one end of the opening / closing control lever 86 rotates the releasable lever 93 in the clockwise direction, so that the claw portion of the releasable lever 93 is rotated.
93a engages with the hooking pin 97a of the primary hook 97, and the reset state is restored in which the primary hook 97 and the secondary hook 99 are engaged. Then, when you release your hand from the control handle 79 in this state, it automatically turns to the “OFF” instruction position, and
To return to the "AUTO" state, the lever is forcibly returned to the "AUTO" position and the state shown in FIGS. 7A to 8B is restored.

Next, an electromagnet for forced opening at the time of short circuit which is a third opening means.
A circuit interruption operation performed via 30 and the link mechanism 18 for forced opening at short circuit will be described with reference to FIGS. 13A and 13B. FIG. 13A is a partially enlarged structural view showing a standby state of the link mechanism for forced opening at the time of short circuit, and FIG. 13B is a partially enlarged sectional view showing an operating state.

Referring to FIG. 13B, when a current larger than the operating current value of the electromagnet 30 for forced opening at short circuit occurs in the main current path, the electromagnet 30 for forced opening at short circuit operates instantaneously, Protruding rod
31 is projected downward. According to the movement of the protruding rod 31, the first
The lever 110 engages the shaft 111 to compress the return spring 115.
Rotate clockwise around. The link member 112 is pushed upward in response to the rotation of the first lever 110, and the second lever 113 is rotated counterclockwise about the shaft 114.
Then, the tip portion of the second lever 113 pushes the opening / closing operation lever 17 downward. As a result, the fixed contact 10 and the movable contact 8 are separated and the contact is released. When the main current path is cut off, the short-circuit forced opening electromagnet 30 connected in series to this main current path is also de-energized, and the projecting rod 31 returns upward. At this time, the link mechanism receives a counterclockwise restoring force by one end of the first lever 110 by the return spring 115, and the other end of the second lever 113 by the contact spring 11 provided below the opening / closing operation lever 17. Receives a restoring force that rotates clockwise. Then, the link material 112 receives restoring forces from both sides in opposite directions, and cancels them to maintain the contact open state. That is, the link mechanism for forced opening upon short circuit constitutes a self-holding type link mechanism. The return operation of the illustrated link mechanism in the self-holding state is performed by further pressing down the opening / closing operation lever 17 by the spring releasing mechanism 75b which is operated by the operation of the overcurrent responding devices 45 and 46 that detect the overcurrent. When the opening / closing operation lever 17 is slightly pushed down, the second lever 13 is released in a powerless state. And return spring
The first lever 110 is rotated counterclockwise by 115, and with this, the link mechanism returns to the state shown in FIG. 13A.

In this short-circuit forced opening link mechanism, when the electromagnet for forced opening during short circuit operates, the contacts are separated by the self-holding type link mechanism described above, and the separated state is maintained,
The safety against re-contact after opening is more reliable and the short-circuit breaking performance is improved.

Further, the circuit breaker according to the present invention has a control handle 79.
It has a "TEST" or "ISOL" mode selected by, and both are in the state where the main current path is cut off. The "TEST" mode is a mode for performing the monitoring operation of the circuit breaker. However, "ISOL" cannot perform monitor operation. In these modes, the disconnecting section 13 is set to the "OFF" state in order to cut off the main current path. FIG. 14 is a disconnection contact opening / closing mechanism diagram showing the opening / closing mechanism of the disconnecting portion 13. With reference to FIGS. 2 and 14, one end of the disconnecting portion opening / closing mechanism abuts the eccentric cam 76, and the shaft 10
A pair of first levers 105 rotatably supported by 6
An L-shaped second lever 107 engaged with the first lever 105 and rotatably supported by a shaft 108; and a second lever 107.
Disconnecting lever for interlocking with 3 poles, which is made of an insulator and is engaged with the tip of the
And 109. A conductor 25 connected to the first fixed conductor 12 and the power source side terminal conductor 16 is mounted inside the three-pole interlocking disconnecting lever 109.

In operation, when the control handle 79 is rotated to the “TEST” or “ISOL” position, the eccentric cam 76 is also rotated, and the first lever 105 abutting on the eccentric cam 76 is rotated counterclockwise. . In response to the rotation of the first lever 105, the second lever 107
Is rotated clockwise, and the three-pole interlocking disconnecting lever 109 that engages with the second lever 107 is lifted upward. As a result, the conductor 25 is detached from the power source side terminal conductor 16 and the first fixed conductor 12 and the main current path is opened. Further, as shown below, the monitor operation can be performed in the “TEST” mode with the limit switch 118 in the “ON” state, and the monitor operation is performed in the “ISOL” mode because the limit switch 118 is in the “OFF” state. I can't.

Next, an electric operation circuit of a switch using the opening / closing operation electromagnet 60 will be described with reference to FIG. The operation connection terminals 115, 116, 117 are installed on the upper terminal shelf of the operation mechanism unit housing 3, and from one side, the power supply connection terminal 115, the exciting coil of the opening / closing operation electromagnet 60, and the limit switch 118.
In addition, a micro switch 119 for self-holding the electromagnet 60 for switching operation is connected in series, and further connected to the other power supply connection terminal 115a via an OFF pushpin 120 for remote operation provided outside the switch. . Power connection terminals 115, 115a
A power source E is connected between them. Further, an ON-push 121 for remote operation, which is provided outside, is connected in parallel between the connection terminals 116 and 117. Limit switch 118 has control handle 79
Is set to "ON" at the "AUTO" and "TEST" positions, and is set to "OFF" at the other switching positions. That is, the limit switch 118 is attached to the fixed frame 80 of the operation control mechanism 75, and the operating lever of the limit switch is attached so as to contact the bent ear piece 87a of the crossbar control lever 87. And, for example, "AUT
The limit switch 118 is held in the “on” position in the “O” position, ie, with the toggle links 90, 92 extended.

Micro switch for self-holding electromagnet 60 for opening and closing operations
119 is mounted on the outer surface of the fixed frame 65 of the operation mechanism unit housing 37, and is attached so that the end of the movable iron core operating pin 73 provided on the movable iron core 62 of the opening / closing operation electromagnet 60 corresponds to the micro switch operating lever. ing. When the movable iron core 62 is attracted to the fixed iron core 61, the movable iron core operating pin
73 is configured to move to hold the actuating lever of the microswitch in the "on" state. Control handle 79
The relationship of "ON" and "OFF" of the disconnecting portion 13, the main contact 5 and the limit switch 118 at each switching position is summarized in the following table.

Thus, the circuit breaker according to the present invention has a fixed contact.
10 and 10 and fixed contacts 10 and 10 and a movable contactor 9 having movable contacts 8 and 8 arranged so as to be openable and closable, and movable contacts 8 and 8 are joined to the fixed contacts 10 and 10 so as to be movable contact. Child 9
The opening / closing operation lever (first contact) that is engaged with each pole so as to operate the contactor spring 11 and the movable contactor 9 mounted on the
Connection means 17), and an electromagnet actuating lever 71 and a crossbar 74 for simultaneously scanning the open / close operation levers 17 of each pole
And a second connecting means consisting of: an electromagnet 60 for opening / closing operation common to each pole, a spring releasing mechanism 75b common to each pole, and an electromagnet 30 for forced opening at the time of each pole short-circuiting electromagnet 30;
It is provided with overcurrent response devices 45 and 46 that detect and respond to overcurrent. When the control handle 79 is normally in the "AUTO" position and the opening / closing operation electromagnet 36 is excited, the contact spring 11 causes the movable contacts 8, 8 to contact the fixed contacts 10, 10 "ON". Is in the state of.

Then, when the opening / closing electromagnet 60 is deenergized, the second connecting means 71, 74 are operated to push down the first connecting means 17 of each pole, open the movable contacts 8, 8, and turn off. Hold in the state of. That is, the opening / closing operation of the main current path is performed by the opening / closing electromagnet 60.

When an overload current flows in the above “ON” state, the electronic overcurrent relay 45 detects an overcurrent and outputs a detection signal, and the release electromagnet 46 operates and transmits in response to the output signal. The primary hook 97 and the secondary hook 99 are disengaged via the plates 54 and 103. Then, the spring releasing mechanism 75b is released to rotate the crossbar control lever 87 and push down the first connecting means 17. As a result, the movable contact 9 is pushed downward and the main current path is separated. Further, the rotation of the crossbar control lever 87 turns off the limit switch 118, and the exciting coil 63 of the opening / closing electromagnet 60 is deenergized. Then, the movable iron core 62 is separated from the fixed iron core 61 and follows the second connecting means 71, 74 which has already been moved to the opened position. In this way, the spring release mechanism is fast in operating speed against overload current.
Since the circuit is cut off due to the collapse of 75b, it is possible to improve the breaking performance of the overload current as compared with the conventional circuit breaker.

Further, when a large current such as a short-circuit current is generated, the electromagnet 30 for forced opening during short circuit is instantly energized so that the protruding rod 31 operates the link mechanism 18 for forced opening during short circuit and the first connecting means 17 Push down to open the contact. At the same time, the electronic overcurrent relay 45 detects a short-circuit current, and the release type electromagnet 46 and the spring release mechanism 75b are operated by the output signals thereof to operate the second connecting means 71, 74 to operate the first connecting means 17
To the open position. Therefore, the electromagnet 30 for forced opening during short circuit operates early to guide the movable contact 9 to the open position, after which the electromagnet 30 for forced opening during short circuit is deenergized and the protruding bar 31 returns upward. The link mechanism for forced opening during short circuit maintains the operating state so as to keep the contacts open, and when the spring release mechanism operates, it automatically returns to the standby state and the open position of the movable contact 9 is maintained. To be done. Therefore, it is not necessary to provide the electromagnet 30 for forced opening at the time of short circuit with a special latch mechanism or reset mechanism for preventing reclosing. By providing the link mechanism 18 for forced opening at short circuit inside the switching breaker housing unit 2, the electromagnet 30 for forced opening at short circuit is connected to the current transformer 41 for detecting current and the overcurrent related to the rated current of the circuit breaker. It can be provided in the trip unit housing 4 together with the overcurrent responding means consisting of the responders 45 and 46. Further, the trip unit housing 4 can be easily removed by removing the screw 24 of the input terminal of the exciting coil 36 of the electromagnet 30 for forced opening at the time of short circuit. As a result,
It is possible to replace the electromagnet 30 for forced opening during short circuit, which has a current capacity and an operation set value corresponding to the rated current, with the overcurrent response means in pairs.

When the rated current is small, the current capacity of the exciting coil 36 of the electromagnet 30 for forced opening during short circuit can be reduced to increase the number of coil turns and increase the resistance value, and the passing short-circuit current can be extremely reduced. . Link mechanism for forced opening at short circuit 18
It is also possible to return to the standby state after the operation by the operation of the spring releasing mechanism 75b described above so that the other opening / closing operation electromagnet becomes non-excited and the opening / closing operation lever 17 is further pushed down. Therefore, the link mechanism 18 for forcibly opening upon short circuit according to the present invention includes the electromagnet 6 for opening / closing the spring releasing mechanism 75b.
It is applicable to a circuit breaker including at least one of 0.

[Effects of the Invention] As described above, according to the present invention, it is possible to reliably prevent a re-entry accident at the time of short-circuit interruption, and to omit an artificial return operation at the time of circuit interruption to automatically restore the circuit interruption. A circuit breaker capable of performing an operation can be realized.

[Brief description of drawings]

FIG. 1 is an external perspective view of a circuit breaker according to an embodiment of the present invention. FIG. 2 is a sectional structural view of the circuit breaker, and FIG. 3 is a plan structural view from a direction along a cutting line XX in FIG. FIG. 4 is a partial structural view showing the first contact opening means of the circuit breaker. FIG. 5 is a plan structural view for explaining the release electromagnet 46 and the transmission mechanism connected to the release electromagnet 46. FIG. 6 is a sectional structural view showing the operation control mechanism. 7A, 9A and 11A are plan structural views of the control handle 79 in each switching position. 7B, 9B and 11B are shown in FIGS. 7A to 11A.
FIG. 8 is a plan structure diagram of an eccentric cam 76 and a slide plate 84 corresponding to the figure. Figures 8A, 10A and 12A show 7A respectively.
FIG. 11 is a sectional structural view of a handle control mechanism portion corresponding to FIGS. 11 to 11A. Figures 8B, 10B and 12B are respectively
FIG. 8A is a sectional structural view of a spring release mechanism corresponding to FIGS. 8A to 12A. FIGS. 13A and 13B are partial cross-sectional structural views showing a link mechanism for forced opening during short circuit, FIG. 13A shows a standby state of the link mechanism, and FIG. 13B shows a contact opened state. FIG. 14 is a disconnection contact opening / closing mechanism diagram showing an opening / closing mechanism for a disconnection contact. FIG. 15 is a circuit block diagram of the circuit breaker. In the figure, 1 is a base, 2 is an opening / closing cutoff unit housing, 3 is an operation mechanism unit housing, 4 is a trip unit housing, 8 is a movable contact, 9 is a movable contactor, and 10
Is a fixed contact, 12 is a first fixed conductor, 13 is a disconnecting part, 14 is a second fixed conductor, 18 is a link mechanism for forced opening at short circuit, 30 is an electromagnet for forced opening at short circuit, and 40 is zero phase Current transformer, 41 is current transformer for current detection, 45 is electronic overcurrent relay, 46 is release type electromagnet, 60 is electromagnet for opening / closing operation, 71 is electromagnet actuating lever, 74
Is a crossbar for interlocking with three poles, 75 is an operation control mechanism, 75a is a handle control mechanism section, 75b is a spring release mechanism section, 76 is an eccentric cam, and 87 is a crossbar control lever. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (5)

(57) [Claims] 1. A fixed contact (10) provided in the middle of a main current path connecting a power supply side circuit terminal (16) and a load side circuit terminal (43), and contacting / disengaging the fixed contact. The movable contact means (9) for opening and closing the main current path, the displaceable first connecting means (17) connected to the movable contact means, and the movable contact means for the fixed contact. A first spring means (11) for urging the main current path to come into contact with the first current means, a current operation type electromagnet (30) which is excited and operates in response to the occurrence of an excessive current of a predetermined value or more in the main current path, A transmission means (18) for transmitting the movement of the die electromagnet to the first connecting means, thereby separating the movable contact means from the fixed contact against the biasing force of the first spring means, and acting on the transmission means. Biasing force of the first spring means,
Separated state maintaining means (110, 112, 113) for fixing the position of the transmitting means and maintaining the separated state of the movable contact means and the fixed contact by balancing the biasing force acting in the opposite direction , With the generation of the excessive current, the movable contact means is moved against the biasing force of the first spring means after the transmission of the force to the movable contact means by the transmission means, whereby the A circuit breaker, comprising: an urging force cutoff means for cutting off the urging force of the first spring means acting on the separated state maintaining means. 2. The first lever (110), wherein the current-operated electromagnet is a plunger type, and the transmission means is rotatably provided, and one end of which is in contact with a plunger (31) of the current-operated electromagnet. And rotatably provided, one end of which is provided with the first connecting means (1
The circuit breaker according to claim 1, further comprising: a second lever (113) that abuts against (7), and a link member (112) that connects the other end of the first lever and the other end of the second lever. vessel. 3. The circuit breaker according to claim 1, further comprising second spring means (115) for urging the transmission means (18) to return to the original position. 4. The biasing force cut-off means includes a fixed portion (61), a movable portion (62) which moves in response to an opening / closing command of the main current path, and the movable portion which is separated from the fixed portion. The voltage-operated electromagnet (60) having a biasing spring (64) and the movement of the movable part (62) biased by the spring are transmitted to the first connecting means (17), whereby the The circuit breaker according to any one of claims 1 to 3, further comprising: second connecting means (74) for moving the movable contact means against the biasing force of the first spring means. 5. The urging force cut-off means is an overcurrent responsive means (45, 46, 50, 5) for detecting and responding to an overcurrent.
4,102,103) and the movement of the overcurrent responsive means to the first connecting means (17), thereby moving the movable contact means against the biasing force of the first spring means (87,90). , 91,9
2,93,97,99), and the circuit breaker according to any one of claims 1 to 3.