JP2003346635A - Circuit breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit breaker which can attain both reliability of a plurality of times of breaking operation and a high breaking performance. <P>SOLUTION: The circuit breaker is provided with a fixed contactor 4, a movable contactor arranged free in getting in and out of contact in opposition to the fixed contactor, a switching mechanism 5 driving the movable contactor, an overcurrent tripper 6 opening and closing the movable contactor by operating the switching mechanism in response to the overcurrent, an arc-extinguishing device 10 extinguishing arcs A1 generated at opening and closing of the movable contactor by separating them with a plurality of arc-extinguishing plates 8, and a pair of a first and a second arc runners 11, 12 inducing the arcs A1 from the contactor pair consisting of the fixed contactor and the movable contactor to the arc-extinguishing device. A first and a second exhaust channels 16, 15 are arranged each communicating with an outside of a chassis body in the vicinity of an end part of the first and the second arc runners at an arc-extinguishing device side, and further, isolating members 11, 26 are provided for isolating the overcurrent draw-out device and the switching mechanism from a gas flow generated from arcs A3 induced to the arc-extinguishing device. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker for breaking a circuit when an overcurrent such as an overload current or a short-circuit current occurs.

[0002]

2. Description of the Related Art FIG.
FIG. 1 is a cross-sectional view showing the inside of a conventional circuit breaker shown in Japanese Unexamined Patent Publication (Kokai) No. H10-15095. 10, 1 is a movable contact, 2 is a movable contact, 3 is a fixed contact, 4 is a fixed contact, 5 is an opening / closing mechanism, 6
Is an overcurrent trip device, 7 is a handle, 8 is an arc extinguishing plate, 9
Is an arc extinguishing side plate, 10 is an arc extinguishing device, 11 is one arc runner (first arc runner), 12 is the other arc runner (second arc runner), 13 is one terminal (first terminal), 14 is the other terminal ( (A second terminal), 150 is an exhaust path, 170 is an exhaust port, 20 is a housing, 24 is an upper space (housing second room), 25 is a lower space (housing first room), 26 is a partition wall, and 29 is a partition wall. A screw, 30 is a square frame, and 31 is a conductor end.

In general, a circuit breaker of this type includes a terminal pair 13 connected to an external electric circuit in a housing 20 made of an insulating material.
14, a fixed contact 4 having a fixed contact 3, a movable contact 1 having a contact portion (movable contact 2) opposed to the fixed contact 3 and arranged to be able to freely contact and separate from the fixed contact 3, An opening / closing mechanism 5 for driving the contact 1, an overcurrent tripping device 6 for operating the opening / closing mechanism 5 in response to an overcurrent to separate the movable contact 1, and an overcurrent tripping device 6 generated when the movable contact 1 is separated. Arc extinguishing device 10 that divides the arc to be extinguished by a plurality of arc extinguishing plates 8 and extinguishes the arc, and the above-mentioned arc extinguishing device 10 comprising It has a pair of arc runners 11 and 12 for inducing an arc up to this point, and an exhaust path 150 for exhausting high-temperature gas generated with the generation of the arc. However, the movable contact 2 or the fixed contact 3
In some cases, the conductive member constituting the movable contact 1 or the fixed contact 4 may be substituted. In FIG. 10, the movable contact 2 is substituted by the conductive member constituting the movable contact 1.
Further, terminal pairs 13 and 14 for connecting external electric wires are respectively arranged on both right and left ends of the housing 20, and a handle 7 for manually operating the opening / closing mechanism 5 is provided on the upper surface of the housing 20.

When an overcurrent is interrupted by such a circuit breaker, the overcurrent trip device 6 operates the opening / closing mechanism 5 in response to the overcurrent, and the contacts 1, 4 are opened. Accordingly, an arc is generated between the contacts 1 and 4. The arc between the contacts 1 and 4 is constituted by a fixed contact-side arc runner 12 connected to the fixed contact 4 by a conductor, and a movable contact-side arc runner 11 connected to the movable contact 1 by a conductor. Arc extinguishing device 1 with a pair of arc runners 11 and 12
Driven to zero. The arc extinguishing device 10 includes a plurality of magnetic material arc extinguishing plates 8 and an arc extinguishing side plate 9 that holds these arc extinguishing plates 8 with a gap therebetween. The arc is extinguished by dividing and cooling.

[0005] The driving force of the arc to the arc extinguishing device 10 can be roughly classified into an electromagnetic force and a force caused by a pressure gradient. The former consists of a force by which the arc is attracted to the magnetic arc extinguishing plate 8 and a Lorentz force by a current flowing through the electric circuit.
On the other hand, in the latter, the arc is driven by the pressure difference before and after the arc. Since the pressure reduction is the arc energy, the pressure difference before and after the arc is caused by increasing the exhaust efficiency in the driving direction from the opposite direction. Therefore, in the conventional circuit breaker, the exhaust path 150 connected to the outside of the housing 20 is provided on the back side of the arc extinguishing device 10 (on the side opposite to the installation side of the contacts 1 and 4).

In order to increase the breaking capacity (the magnitude of overcurrent that can be broken) of such a circuit breaker, a larger arc energy must be processed by the arc extinction device 10. Needs to be enlarged. Also, the arc extinguishing device 10 and the contacts 2 and 3 (the fixed contact 3 and the movable contact 2) are connected so that the arc driven by the arc extinguishing device 10 and having higher energy does not return between the contacts 1 and 4. ) Must be relatively long. On the other hand, the external dimensions of the circuit breaker are required to be a contracted dimension or smaller in order to be easily incorporated into a switchboard or the like and to be downsized. Therefore, as shown in FIG. 11, the space for driving the arc by the arc runners 11 and 12 and the housing 2 of the space occupied by the arc extinguishing device 10 are provided.
The space occupancy within 0 is necessarily high.

FIG. 11 is a sectional view showing the inside of another conventional circuit breaker having a large breaking capacity. In FIG.
Reference numeral 19 denotes a flexible conductor that electrically connects the movable contact 1 and the terminal 14. Compared with the circuit breaker shown in FIG. 10, the space occupied by the space for driving the arc by the arc runner and the space occupied by the arc extinguishing device 10 are larger.
Accordingly, the cross section of the exhaust path 150 provided on the side opposite to the installation side of the contacts 1 and 4 of the arc extinguishing device 10 (the back side of the arc extinguishing device 10) becomes smaller. Generally, terminal pairs 13 and 14 are provided at both left and right ends (both ends in the direction in which the arc runners 11 and 12 extend) of the circuit breaker. The terminal pairs 13 and 14 are provided with a handle for manual operation. Since an operation such as fastening of the screw 29 is performed from the upper surface side of the terminal 7, the exhaust port 170, which is an opening of the exhaust path 150 to the outside of the housing 20, is necessarily located below the terminal 13 (the arc extinguishing device 1).
0 lower side). Therefore, when the cross section of the exhaust path 150 is reduced as described above, the arc extinguishing device 1
The exhaust efficiency from the upper side of the rear surface 0 is significantly lower than the exhaust efficiency at the lower side of the rear surface of the arc extinguishing device 10 near the exhaust port 170. Accordingly, the driving force caused by the pressure gradient acting on the upper part of the arc becomes smaller than that of the lower part of the arc, and the driving force in the vertical direction of the arc becomes uneven.
Due to this unevenness, the second arc runner 1 located below
Since the arc spots on the two sides run ahead of the arc spots on the first arc runner 11 located on the upper side, and the arc is inclined with respect to the arc extinguishing plate 8, all the provided arc extinguishing plates 8 are effective. To break the arc and prevent cooling.

FIG. 11 schematically shows the movement of this arc. In FIG. 11, A1 is an arc generated between the movable contact 2 and the fixed contact 3 due to the opening of the movable contact 1, and this arc A1 is generated by the above-described driving force (the force caused by the electromagnetic force and the pressure gradient). It is driven from arc A2 to arc A3. B1 and B2 are arrows indicating the flow of exhaust gas. The arc A3 shows a state in which the arc is oblique to the arc extinguishing plate 8, and the arc extinguishing plate 8 provided above is not used for dividing and cooling the arc A3. In a state where the driving of the arc spot on the side of the arc runner 11 located above is insufficient, the arc A3 easily returns between the contacts 1 and 4, and the current limiting performance is reduced and interruption is impossible.

[0009]

As described above,
In a conventional circuit breaker, if an attempt is made to increase the breaking capacity without increasing the size, the cross-sectional area of the exhaust path becomes smaller, and the exhaust efficiency from the upper side of the back of the arc extinguishing device becomes lower. Since the exhaust efficiency is significantly lower than the exhaust efficiency, the arc spot on the side of the second arc runner 12 located below runs ahead of the arc spot on the side of the first arc runner 11 located above, and the arc A3 is turned off by the arc extinguishing plate 8. As a result, the arc A3 cannot be divided and cooled by effectively using all the provided arc extinguishing plates 8,
There is a problem that the arc A3 easily returns between the contacts 1 and 4, and the current limiting performance is reduced and interruption is impossible.

In order to solve such a problem, as shown in FIG. 12, an overcurrent tripping device 6 and an opening / closing mechanism 5 are provided near the end of the first arc runner 11 located above the arc extinguishing device 10 side. A configuration is conceivable in which a communication port 42 that communicates with the upper space 24 inside the housing is provided. Since the communication port 42 improves the exhaust efficiency near the end of the first arc runner 11 located on the arc extinguishing device 10 side located above, the above-described unevenness in driving the arc in the vertical direction hardly occurs. As a result, the arc A1 generated between the contacts 2 and 3
Is driven from the arc A2 to the arc A3 by the electromagnetic force and the flow of exhaust gas indicated by arrows B1, B2, and B4 in the figure, and is separated and cooled by all the provided arc-extinguishing plates 8.

In FIG. 12, reference numeral 27 denotes an exhaust path 15
The rectifier plate is provided near the arc extinguishing device 10 at 0 and adjusts the flow of exhaust gas, and has a discontinuous opening in the vertical direction in FIG. This opening corresponds to CC in FIG.
As shown in FIG. 13 which is a line cross section, the exhaust gas is arranged at the center so that the exhaust gas flows to the center. Reference numeral 33 denotes a heat-resistant cover for protecting a part of the overcurrent trip device 6 near the communication port 42 from a high-temperature gas flow accompanying the arc. B
Is an arrow indicating the exhaust flow passing through the current plate 27.

However, in such a circuit breaker, an arc is generated in the upper space (housing second chamber) 24 in the housing 20 containing the overcurrent trip device 6 and the switching mechanism 5. A hot gas containing the generated melt flows in. Although a part of the overcurrent tripping device 6 is protected by the heat-resistant cover 33, most of the overcurrent tripping device 6 and the switching mechanism 5 are exposed to the high-temperature gas accompanying the arc. become. As a result, there has been a problem that the overcurrent tripping device 6 having the movable portion and the opening / closing mechanism 5 are damaged by the high-temperature gas, so that the opening / closing operation after the shutoff operation or the re-shutoff operation cannot be performed.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and is intended for use in a case where the breaking capacity is increased or the size is reduced without increasing the size.
Without exposing the overcurrent tripping device and the switching mechanism to the high-temperature gas accompanying the arc, the pressure imbalance in the vicinity of the arc extinguishing device side end of the pair of arc runners is prevented, and the reliability of the breaking operation multiple times is improved. An object of the present invention is to provide a circuit breaker that can achieve both high breaking performance.

[0014]

According to the present invention, there is provided a circuit breaker including a fixed contact, a movable contact opposed to and fixed to the fixed contact inside a housing; An opening / closing mechanism for driving the movable contact, an overcurrent trip device for operating the opening / closing mechanism in response to an overcurrent to open the movable contact, and an arc generated when the movable contact is opened. An arc extinguishing device that extinguishes the arc by dividing the arc by a plurality of arc extinguishing plates, and a pair of first and second guides that guide the arc from the contact pair including the fixed contact and the movable contact to the arc extinguishing device.
A circuit breaker provided with an arcrunner;
And first and second exhaust paths communicating with the outside of the housing are disposed near the arc extinguishing device-side end of the second arc runner, respectively.
Further, there is provided a separating member for separating the overcurrent tripping device and the opening / closing mechanism from a gas flow generated from the arc induced by the arc extinguishing device.

Further, a first chamber for housing an arc extinguishing device arranged between the pair of first and second arc runners, and an extra space arranged on a side of the first arc runner opposite to the arc extinguishing device arrangement side. A housing second chamber for accommodating the current trip device and the opening / closing mechanism, and a side opposite to the contact pair installation side of the arc extinguishing device, disposed adjacent to the housing first and second chambers;
A third housing for housing a square frame, into which a screw is attached and which connects an external electric wire inserted into the frame from outside the housing to the conductor end from one of the contact pairs by fastening the screw; The first exhaust path is provided so as to communicate with the outside of the housing through a gap between the outer surface of the square frame and the inner wall of the third housing of the housing, and the second exhaust passage is provided in the housing. It is provided between the third chamber and the second arc runner.

Further, the screw is mounted so as to be screwed into the square frame from the side opposite to the side on which the second exhaust path is provided, and the first exhaust path is formed of the square frame. The second exhaust passage is provided so as to communicate with the outside of the housing through a gap between at least one of the outer surface on the side of the second exhaust passage and the two outer surfaces following the inner surface and the inner wall of the housing third chamber. is there.

Further, a communication path is provided for connecting the first exhaust path and the second exhaust path in the middle of each exhaust path.

Further, the screw is mounted so as to be screwed into the square frame from the side opposite to the side on which the second exhaust path is provided, and the first exhaust path is formed of the square frame. It is provided so as to communicate with the outside of the housing through a gap between the outer surface on the screw insertion side and the inner wall of the housing third chamber.

Further, a housing fourth chamber isolated from the screw is provided between the screw head and the inner wall of the housing third chamber.
The housing is provided so as to communicate with the outside of the housing through the housing fourth chamber.

Further, the circuit breaker according to the present invention includes a fixed contact, a movable contact opposed to the fixed contact so as to freely contact and separate from the fixed contact, and the movable contact inside the housing. A driving opening / closing mechanism, an overcurrent trip device for operating the opening / closing mechanism in response to an overcurrent to release the movable contact, and a plurality of arc extinguishing arcs generated when the movable contact is opened. An arc extinguishing device that extinguishes the arc by dividing it with a plate, and a pair of first exciters that guides the arc from the pair of contacts to the extinguishing device.
A circuit breaker including a first arc runner and a second arc runner, the first arc runner having a first housing for accommodating an arc extinguishing device disposed between the pair of first and second arc runners; A second chamber disposed on the opposite side to accommodate the overcurrent trip device and the opening / closing mechanism; and an exhaust disposed near an end of the second arc runner on the arc extinguishing device side and communicating with the outside of the casing. A path, a communication port for connecting the first housing chamber and the second housing in the vicinity of the end of the first arc runner on the arc extinguishing device side, and the communication port and the opening / closing mechanism or the overcurrent trip device. And a cooling plate for flowing gas to cool the cooling plate, and separating the gas flowing from the first chamber through the communication port from the opening / closing mechanism and the overcurrent tripping device. And a guiding member for guiding It is.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a sectional view showing the configuration of the circuit breaker according to Embodiment 1 of the present invention. In FIG. 1, 1 is a movable contact, 2 is a movable contact 1
(Movable contact), 4 are fixed contacts, 3 is a contact (fixed contact) of the fixed contact 4, and the movable contact 1 is disposed so as to be able to freely contact and separate from the fixed contact 4. The movable contact 2 or the fixed contact 3 may be replaced by a conductive member constituting the movable contact 1 or the fixed contact 4.
Reference numeral 5 denotes an opening / closing mechanism for driving the movable contact 1, reference numeral 6 denotes an overcurrent trip device for operating the opening / closing mechanism 5 in response to an overcurrent to open the movable contact 1, and reference numeral 7 denotes a manual operation of the opening / closing mechanism 5. Handle. 8 is an arc-extinguishing plate, 9 is an arc-extinguishing side plate, 1
Reference numeral 0 denotes an arc extinguishing device that extinguishes an arc generated when the movable contact 1 is separated by a plurality of arc extinguishing plates 8. The arc-extinguishing device 10 includes a plurality of arc-extinguishing plates 8 made of a magnetic material and an arc-extinguishing side plate 9 that holds these arc-extinguishing plates 8 with a gap therebetween.
The driven arc is divided and cooled by an arc extinguishing plate 8 to extinguish the arc. Reference numerals 11 and 12 denote a pair of arc runners for guiding an arc from the contact 1, 4 pairs (comprising the fixed contact 4 and the movable contact 1) to the arc extinguishing device 10, 11 is a first arc runner, and 12 is a second arc runner. I'm Arcranna. The arc extinguishing device 10 is disposed between the pair of first and second arc runners 11 and 12. That is, in FIG. 1, the pair of first and second arc runners 11 and 12 are arranged so as to sandwich the arc extinguishing device 10 from above and below.

Reference numeral 13 denotes one terminal (first terminal) on the back side of the arc extinguishing device 10, that is, on the side opposite to the side where the contacts 1, 4 are installed.
Terminal 29), the screw 29, the square frame 30 and the contact 1,
The arc extinguishing device 10 constituted by the conductor end 31 from one of the four pairs (the fixed contact 4 in the case of FIG. 1) and similarly constructed
Other terminals (second terminals) on the side where the contacts 1, 4 are installed
14 and a terminal pair. The square frame 30 is provided with a screw 29, and the external electric wire 21 for circuit interruption inserted into the square frame 30 from the outside of the housing 20 by fastening the screw 29 from the outside of the housing 20 from one of the contact pairs. It is configured to be connected to the conductor end. More specifically, the screw 2 is
9 is screwed into a female screw hole, and the housing 2
The conductor end of the external electric wire 21 from the outside is inserted and the screw 29 is tightened, so that the conductor end of the external electric wire 21 is sandwiched and fixed between the square frame 30 and the conductor end 31. The terminal pairs 13 and 14 are connected to the arc runner 1 of the housing 20.
Screws 29 are provided at both ends (left and right ends in FIG. 1) in the extending direction of the first and second 12, and are screwed into the square frame 30 from the side opposite to the second exhaust path 15 (upper side in FIG. 1). It is arranged to be inserted. 37 is a housing third chamber 130
The surface on the side opposite to the second exhaust passage 15 (in FIG.
30 and an opening for screw operation provided on the upper surface of the housing 20).

Reference numeral 15 denotes an arc extinguishing device 1 for the second arc runner 11.
A second exhaust passage (exhaust passage at the bottom in FIG. 1) provided near the 0-side end and communicating with the outside of the housing 20, and 16 is provided near the end of the first arc runner 12 on the arc extinguishing device 10 side. A first exhaust path (exhaust path at the top in FIG. 1) that communicates with the outside of the housing 20 is provided, 17 is a second exhaust port (an exhaust port at the bottom in FIG. 1), and 18 is a first exhaust port (FIG. 1). , The exhaust port at the top), 19 is the movable contact 1 and the terminal 14
Is a flexible conductor for electrically connecting the above, and 20 is a housing made of an insulating material.

Reference numeral 24 denotes a second chamber (a space at the top in FIG. 1) of the housing, which is arranged on the side opposite to the arc extinguishing device arrangement 10 side of the first arc runner 11, that is, on the side opposite to the arc extinguishing device.
The overcurrent trip device 6 and the switching mechanism 5 are housed. 2
Reference numeral 5 denotes a first chamber (a space at the bottom in FIG. 1) for accommodating the arc extinguishing device 10 disposed between the pair of first and second arc runners 11 and 12. A handle for manually operating the opening / closing mechanism 5 is provided on a surface of the second housing 24 opposite to the side where the first housing 25 is disposed (the upper surface of the second housing 24 and the upper housing 20 in FIG. 1). 7 are provided. Reference numeral 130 denotes a housing third chamber, which is provided on the rear side of the arc extinguishing device 10, that is, on the side opposite to the installation side of the contacts 1 and 4 (the left side in FIG. 1) and the housing first chamber 25 and the second chamber 24. The square frame 30 which is disposed adjacently and has the screw 29 mounted therein is stored. Reference numeral 26 denotes a partition wall that partitions the first housing chamber 25 and the second housing chamber 24 together with the first arc runner 11, and the first arc runner 11 and the partition 26 connect the overcurrent tripping device 6 and the opening / closing mechanism 5 to the arc extinguishing device 10. Corresponding to a gas flow generated from the arc guided by the arc. The partition 26 is also a partition that partitions the first housing 25 and the third housing 130. A1, A2, and A3 are arcs. B1, B2, B
3 is an arrow indicating the flow of exhaust gas.

FIG. 2 is a sectional view taken along line CC of FIG. In FIG. 2, reference numeral 261 denotes a communication port provided on the partition wall 26 and partially communicating the first casing 25 and the third casing 130. Reference numerals 130a and 130b denote gaps between outer surfaces of upper and lower sides (front and rear in FIG. 1) of the square frame of the third housing chamber 130 and inner walls of the third housing chamber 130 facing these outer surfaces. It is. 1 and 2, 27
Is the arc extinguishing device 1 in the first and second exhaust passages 16 and 15.
0, which is a flow straightening plate for adjusting the flow of exhaust gas, as shown in FIG. 2, having a discontinuous opening in the vertical direction in FIG. So that it is arranged in the center.

In the present embodiment, the partition 26 that partitions the first housing 25 and the third housing 130 is provided with a communication port that partially connects the first housing 25 and the third housing 130. 261 is provided, and the first exhaust path (upper exhaust path) 16 is
The gaps 130a, 130b between the vicinity of the arc extinguisher 10 side end of the arcrunner 11, the opening of the current plate 27, and the outer surface of the square frame 30 and the inner wall of the third housing 130.
The housing 20 is provided so as to communicate with the outside of the housing 20. In more detail, as shown in FIG. 2, the communication port 261 is formed in the vicinity of the end of the first arc runner 11 of the first housing 25 on the arc extinguishing device 10 side and in the shape of a square of the third housing 130 of the housing. Frame 3
0 in FIG. 1, gaps 130a, 1b between the front and rear outer surfaces and the inner wall of the housing third chamber 130 facing these outer surfaces.
30b, and a first exhaust path (upper exhaust path).
16 passes through the opening of the current plate 27 from the vicinity of the end of the first arc runner 11 on the arc extinguishing device 10 side, and further forms the gap between the outer surface of the square frame 30 and the inner wall of the third housing 130. 2 are provided so as to communicate from the first exhaust port 18 to the outside of the housing 20 through gaps 130a and 130b which are vertically located in FIG. 2 (front and rear in FIG. 1). Also, the second
The exhaust path (lower exhaust path) 15 is provided between the third chamber 130 of the housing and the second arc runner 12, and closes the opening of the rectifying plate 27 from near the end of the second arc runner 12 on the arc extinguishing device 10 side. The second exhaust port 17 is provided so as to communicate with the outside of the housing 20 through the second exhaust port 17.

In the above configuration, the arc A1 generated between the contacts at the time of the overcurrent cutoff operation is generated by a force due to a pressure gradient (indicated by an arrow B1 in FIG. 1) and an electromagnetic force from the arc A2 to the arc A3. And the arc is extinguished and cooled by the arc extinguishing device 10, and the current is interrupted.

At this time, the back side of the arc extinguishing device 10, that is, the side opposite to the contact 1, 4 pair installation side (left side in FIG. 1).
Since the first and second exhaust passages 16 and 15 are respectively provided from the vicinity of the ends of the pair of arc runners 11 and 12 on the side of the arc extinguishing device 10 to the external space of the housing 20, the pair of first and second arc runners are provided. An imbalance of driving force does not occur between the first arc runner 11 side (upper part in FIG. 1) and the second arc runner 12 side (lower part in FIG. 1) of the arc transferred between 11 and 12.
The arc A3 guided to the arc extinguishing device 10 is substantially perpendicular to the arc extinguishing plate 8, and is divided by all the provided arc extinguishing plates 8,
Cooled. Further, the second housing (upper space) 24 for housing the overcurrent trip device 6 and the opening / closing mechanism 5 and the arc extinguishing device 1
Since the first chamber (lower space) 25 for housing 0 is separated by the separating member (the partition 26 and the first arc runner 11), that is, by the partition 26 and the first arc runner 11,
The overcurrent trip device 6 and the switching mechanism 5 are connected to the arc extinguishing device 10.
Is isolated from the gas flow generated from the arc A3 induced by the arc, so that the high-temperature gas containing the melt generated due to the arc does not touch the overcurrent tripping device 6 and the switching mechanism 5. Therefore, it is possible to achieve both reliability of a plurality of breaking operations and high breaking performance.

Further, the direction of exhausting the high-temperature gas generated by the arc is directed to the first terminal 13 on the back side of the arc extinguishing device 10 (to the left in FIG. 1), so that the circuit for operating the handle 7 is cut off. The exhaust in the upper direction facing the operator of the vessel can be eliminated, and the upper first exhaust passage 16 is formed in the square frame 3 of the first terminal 13 on the back side of the arc extinguishing device 10.
0 and both outer surfaces in front and back and the housing third chamber 13
0 through the gaps 130a, 130b with the inner wall of the exhaust port 1
Since the communication is made to 8, the vicinity of the arc extinguishing device 10 end of the first arc runner 11 located above can be efficiently exhausted without being hindered by the arrangement of the terminals 13. In addition, the external electric wire 2 inside the square
The first exhaust path 16 can be configured without exposing the threads and the screw heads outside the square frame 30 in addition to the high-temperature gas accompanying the arc in addition to the first and conductor ends 31 and the threads. Damage and fusion of the external electric wire 21, the conductor end 31 and the screw 29 due to the gas can be prevented.

Further, in the present embodiment, the flow regulating plate 27 is provided, and the exhaust flow (indicated by an arrow B in FIG. 2) is devised so as to flow to the center. The arc A3 is stably divided at the relatively center of the arc-extinguishing plate 8 without moving in the front-rear direction in FIG. 1 (vertical direction in FIG. 2) and short-circuiting in the vertical direction in FIG. Is maintained. However, the rectifying plate 27 does not necessarily have to be provided, and the same applies to each of the following embodiments, although not particularly mentioned.

In FIG. 2, the first exhaust passage 16 is connected to the front and rear sides (up and down in FIG. 2) of the square frame 30 of the first terminal 13 on the back side of the arc extinguishing device 10 in FIG. Gap 130a, 130b between the surface and the inner wall of housing third chamber 130
, And communicates with the first exhaust port 18, but may pass only one of the gaps 130 a and 130 b.

The first exhaust port 18 may use the opening for inserting the external electric wire 21 as it is, or may use the external electric wire 21.
A new opening extending upward in FIG. 1 from the insertion opening may be provided.

Embodiment 2 FIG. FIG. 3 is a sectional view showing a configuration of a main part of a circuit breaker according to Embodiment 2 of the present invention.
The overall configuration of the circuit breaker according to Embodiment 2 of the present invention is the same as that of FIG. 1, and FIG. 3 is a cross-sectional view taken along line CC of FIG.
In FIG. 2 shown in the first embodiment, a straightening plate 27 having an opening at the center so that the exhaust flow near the arc A3 flows to the center is used, and the first exhaust path 16 is connected to the vicinity of the arc A3. In FIG. 2, a square frame 30 of the first terminal 13 on the back side of the arc extinguishing device 10 is formed from a space sandwiched by ribs provided so that an exhaust flow (indicated by an arrow B) flows in the center. Gaps 130a, 130b between upper and lower outer surfaces (front and rear in FIG. 1) and the inner wall of the third housing 130.
Through at least one of them.
In contrast, in the present embodiment, as shown in FIG.
Openings are provided at the top and bottom in FIG. 3 (front and back in FIG. 1),
From these openings, the outer surfaces of the square-shaped frame 30 of the first terminal 13 on the back side of the arc extinguishing device 10 which are upper and lower in FIG. 3 (front and rear in FIG. 1) and the inner wall of the housing third chamber 130 Through the gaps 130a and 130b between the air outlet and the exhaust port 18. By configuring the first exhaust path 16 in such a manner, there is an advantage that the exhaust path becomes more linear and the exhaust efficiency is increased as compared with the first embodiment.

When the first exhaust path 16 is configured in this manner, the exhaust flow is deviated in either the front-rear direction in FIG. 1 (vertical direction in FIG. 3), and this deviation causes the arc A3 to move in the front-rear direction in FIG. 3 (vertical direction in FIG. 3), short-circuiting in the vertical direction in FIG. 1 beside the arc-extinguishing side plate 9, there is a possibility that the divided state by the plurality of arc-extinguishing plates 8 cannot be stably maintained. Therefore, in the present embodiment, as shown in FIG. 3, the first arc runner 11 (shown by a two-dot chain line in FIG. 3).
The width W1 (width in the front-rear direction in FIG. 1) at the end of the arc extinguishing device 10 is smaller than the width W2 (width in the front-rear direction in FIG. 1) of the arc-extinguishing plate 8 so that the arc in the front-rear direction in FIG. It is configured to prevent blurring.

It should be noted that the second exhaust passage 15
Regarding the flow straightening plate 27 near the arc extinguisher 10 side end of the arcrunner 12, an opening may be provided at the center as in the first embodiment, so that the exhaust flow may flow to the center.

Embodiment 3 FIG. 4 is a sectional view showing a configuration of a circuit breaker according to Embodiment 3 of the present invention. In FIGS. 2 and 3 shown in the first and second embodiments, the first exhaust path 16 is formed by the square frame 30 of the first terminal 13 shown in FIG.
In at least one of the gaps 130a and 130b between the upper and lower outer surfaces (front and rear in FIG. 1) and the inner wall of the housing third chamber 130, the air was communicated to the exhaust port 18. On the other hand, in the present embodiment, as shown in FIG. 4, the outer surface of the square frame 30 on the second exhaust path 15 side (the lower side of the square frame 30 in FIG. 4) It passes through the gap with the inner wall of the third body chamber 130 and communicates with the exhaust port 18.

The terminal 13 is composed of a screw-shaped frame 30 having a screw 29 and a female screw hole, and a conductor end 31. By tightening the screw 29, the end of the external electric wire 21 is turned into a square-shaped frame 30.
In the state where the external electric wire 21 is connected, the outer surface of the square frame 30 on the side of the second exhaust path 15 and the inner wall of the third housing 130 of the housing are fixed. A space in which an exhaust path is provided can be ensured, and the first embodiment can be used.
2 are provided on both outer surface sides of the upper and lower sides (front and rear in FIG. 1) of the square frame 30 described in FIGS.
The width in the front-rear direction in FIG. 1 can be increased. Therefore, in addition to the effects described in the first embodiment, the exhaust flow rate of the first exhaust path 16 can be increased, and the driving force of the arc due to the pressure gradient can be increased. Since the generated arc A1 can be guided to the arc extinguishing device 10 earlier than before the overcurrent increases,
The effect that the current limiting performance and the blocking performance are further improved can be obtained.

In FIG. 4, reference numeral 32 denotes the first exhaust path 1.
6 and the second exhaust path 15 communicate with each other in the middle of each of the exhaust paths. In the present embodiment, the upper first exhaust path 16 and the lower second exhaust path 15 are connected to the first terminal 13. A communication path 32 communicating with the side opposite to the screw insertion side (the lower part in FIG. 4) is provided. With this communication path 32, the pressure difference between the first exhaust path 16 and the second exhaust path 15 on the arc extinguishing device 10 side can be reduced, and the driving force due to the pressure gradient acting on the arc can be made more uniform.

The first exhaust path 16 is provided with a square frame 30
The gap between the outer surface on the second exhaust path 15 side and the inner wall of the housing third chamber 130 and at least one of two outer surfaces following the outer surface on the second exhaust path 15 side of the square frame 30. It may be provided so as to communicate with the outside of the housing 20 through both one of the surfaces and the gap between the inner wall of the housing third chamber 130. In short, the second exhaust of the square frame 30 is essential. It is provided so as to communicate with the outside of the housing 20 through a gap between at least one of the outer surface on the road 15 side and at least one of the following two outer surfaces and the inner wall of the third housing 130. For example, in addition to the external electric wire 21, the conductor end 31, and the screw thread inside the square frame 30, the screw thread and the screw head outside the square frame 30 are also exposed to the high-temperature gas accompanying the arc. The first exhaust path 16 can be configured without exposure, and the high-temperature gas damages the external electric wire 21, the conductor end 31 and the screw 29. The or fusion can be prevented.

Embodiment 4 FIG. FIG. 5 is a sectional view showing a configuration of a circuit breaker according to Embodiment 4 of the present invention. In FIG. 5, reference numeral 33 denotes a heat-resistant cover provided on a part of the overcurrent trip device 6, and is made of a heat-resistant material such as a resin. Reference numeral 34 denotes a partition wall that separates the housing second chamber 24 and the housing third chamber 130 together with the partition wall 26, 35 denotes an opening provided between the partition walls 26 and 34, and 36 denotes a portion near the screw head of the housing third chamber 130. The provided exhaust port 42 is provided on the partition wall 26 near the end of the first arc runner 11 on the arc extinguishing device 10 side, and is a communication port for communicating the first housing chamber 25 and the second housing chamber 24.

In each of the above-described embodiments, the first exhaust passage 16 is formed by the outer surface of the square frame 30 on the second exhaust passage 15 side and at least one of the two outer surfaces following the outer surface. Although the case has been described in which the first exhaust passage 16 is provided so as to communicate with the outside of the housing 20 through the gap with the inner wall of the third body chamber 130, in the present embodiment, the first exhaust path 16 is Is provided so as to communicate with the outside of the housing 20 through a gap between the outer surface on the screw 29 insertion side and the inner wall of the housing third chamber 130.

In a circuit having a large current carrying capacity, the diameter of the electric wire used becomes large, so that the square frame 30 forming the terminals 13 and 14 also becomes large, and the end of the external electric wire 21 is placed inside the square frame 30. And the screw 29 is tightened, the outer surface of the square frame 30 on the side of the second exhaust passage and the housing third
The gap between the inner wall of the chamber 130 (the lower side of the square frame 30 in FIG. 5), the two outer surfaces following the outer surface of the square frame 30 on the second exhaust path 15 side, and the housing third Both the gap with the inner wall of the chamber 130 (the front and rear sides of the square frame 30 in FIG. 5) are small, and it may be difficult to provide an exhaust path in these gaps. Even in such a case, as in the present embodiment, the first exhaust path 16 is connected to the screw 29 of the square frame 30.
If the first exhaust path is provided near the end of the first arc runner on the arc extinguishing device side, the first exhaust path is provided so as to communicate with the outside of the housing 20 through the space between the outer surface on the insertion side and the inner wall of the third housing 130. The first exhaust path 16 can be configured without exposing the external electric wire 21, the conductor end 31, and the screw thread inside the square frame 30 to the high-temperature gas accompanying the arc. Damage and fusion of the external electric wires 21 and the like due to the high-temperature gas can be prevented.

Hereinafter, the configuration of the main part of the circuit breaker according to the present embodiment will be described in more detail. In the embodiments described above, the housing second chamber 24 and the housing first chamber 25 are separated from each other by a part of the partition wall 26 and the first arc runner 11. As shown in FIG. 5, a part of the partition wall 26 is removed, and the housing second chamber 24 (upper space)
And the first casing 25 (lower space) through the communication port 42 so that a part of the high-temperature gas accompanying the arc flows from the lower space 25 to the upper space 24 side, and the upper space 2
A partition 34 and another opening 35 are provided to guide the high-temperature gas flowing into the opening 4 to the screw 29 in the third housing 130 so as not to flow into the opening / closing mechanism 5. In the present embodiment, the first arc runner 11, the heat-resistant cover 3
The 3 and the partition 34 correspond to an isolation member that isolates the overcurrent trip device 6 and the switching mechanism 5 from the gas flow generated from the arc induced by the arc extinguishing device 10.

In such a structure, high-temperature gas flows into the upper space 24 through the communication port.
Exhaust ports 36 and 37 are provided near the screw head of the third housing 130 to secure an exhaust route to the outside of the housing 20 (third chamber 130). 33 and the partition wall 34, almost all of the inflowing high-temperature gas flows into the screw 29 side (the housing third chamber 130
Side) and is exhausted out of the housing 20, so that the overcurrent tripping device and the switching mechanism are not exposed to the high-temperature gas accompanying the arc, and the overcurrent tripping device 6 and the switching mechanism 5 are not exposed. The chance of damage to the device is extremely low.

In FIG. 5, the screws 2 of the square frame 30 are shown.
The high-temperature gas flow that has flowed into the gap between the outer surface on the insertion side 9 and the inner wall of the housing third chamber 130 is opposite to the side on which the first exhaust path 15 of the housing third chamber 130 is installed (upward in FIG. 5). The housing 20 is formed by a screw operation opening 37 provided in the housing 20 and another exhaust port 36 provided on the opposite side (left side in FIG. 5) of the housing first and second chambers 25 and 24 of the housing third chamber 130. (Housing Third Room 1
30) Although the air is exhausted to the outside, the screw operation opening 3 is provided in order to eliminate the exhaust in the upward direction facing the operator who cuts off the circuit operating the handle 7 and to enhance the safety of the operator.
7 may be closed by another member.

Embodiment 5 FIG. FIG. 6 is a sectional view showing a configuration of a circuit breaker according to Embodiment 5 of the present invention. In FIG. 6, reference numeral 38 denotes a housing fourth chamber provided between the screw head and the inner wall of the housing third chamber 130 so as to be separated from the screw 29. In the present embodiment, the first exhaust passage 16 is , Is provided so as to communicate with the outside of the housing 20 through the housing fourth chamber 38.
Reference numeral 39 denotes a partition wall that partitions the third housing chamber 130 and the fourth housing chamber 38. Reference numeral 22 denotes a tubular insulating cap inserted into the screw operation opening 37, which partitions the housing fourth chamber 38 from the screw operation opening 37, and connects the housing third chamber 130 to the outside of the housing 20. Is in communication. FIG. 7 shows the fourth housing 3 of the housing.
In order to explain a more specific structure of FIG. 8, the vicinity of the screw operation opening 37 is shown in an exploded perspective view. In FIG. 7, 40
a and 40b are a base and a cover.

In the present embodiment, the housing 20 includes the base 40a and the cover 40 that are substantially plane-symmetric with respect to the arc driving surface.
b, a screw operation opening 37 is provided in a portion of the screw 29 located on the side (upper in FIG. 6) opposite to the side on which the second exhaust path 15 is provided. Further, by inserting the tubular insulating cap 22 into the screw operation opening 37, the third housing chamber 1 serving as a screw storage space is formed.
The housing 30 and the housing fourth chamber 38 serving as the first exhaust path 16 can be completely separated.

In the above configuration, the high-temperature gas flowing into the upper space 24 from the communication port 42 is guided to the screw operation opening 37 side by the partition wall 34 and the opening 35, and The air is exhausted to the outside 20 of the housing without touching the screw 29 through the four chambers 38. Therefore, the square frame 3
The first exhaust path 16 can be configured without exposing the threads and the screw heads outside the square frame 30 in addition to the external electric wires 21 and the threads inside the inner wire 0 to the high-temperature gas accompanying the arc, The screw 29 after the overcurrent cutoff operation is different from the case of the fourth embodiment.
There is an advantage that the reliability of operation is increased.

In FIG. 7, the housing 20 includes a base 40a and a cover 40b which are substantially symmetrical with respect to the arc driving surface.
, And is easy to manufacture. However, another configuration (for example, a configuration in which the dimension of the base 40a in the front-rear direction in FIG. 6 is larger than the dimension of the cover 40b in the same direction) may be used. Needless to say.

FIG. 8 is a perspective view showing the vicinity of the square frame 30. In FIG. 8, reference numeral 30a denotes a female screw hole cut into the square frame 30 and screwed to the screw 29. In the first to fourth embodiments described above, the square frame 30 is set on the opposite side to the installation side of the second exhaust path 15 by tightening the screw 29 (FIG. 1).
Then, the external electric wire 21 inserted into the square-shaped frame 30 is sandwiched between the square-shaped frame 30 and the conductor end 31 to connect the external electric wire 21 with the terminal portion. Was. On the other hand, in the present embodiment shown in FIGS. 6 and 8,
By tightening the screw 29 (FIG. 8 shows a state in which the screw 29 is not mounted), the square frame 30 does not move, and the screw 29 is placed on the second exhaust path 15 installation side (downward in FIG. 6).
And the end of the external electric wire 21 is sandwiched between the screw 29 and the square frame 30. When the terminal having such a configuration is used, even when the external electric wire 21 is connected, the square frame 30 does not move to the side opposite to the installation side of the second exhaust path 15 (upward in FIG. 6). The first exhaust path 16 is provided on the second exhaust path 15 side of the square frame 30 (between the outer surface of the square frame 30 on the second exhaust path 15 side and the inner wall of the housing third chamber 130). It becomes difficult.

Further, in the present embodiment, the conductor end 31 and the square frame 30 are integrally formed of the same member to reduce the number of parts. The square frame 30 to which a large force is applied when the external electric wire 21 is attached (during tightening) is generally made of iron, which is a general structural material. When integrally forming the frame 30 with the same member, a metal having high conductivity, for example, copper, aluminum or the like is used. Since these metals have lower mechanical strength than iron, the thickness of the square frame 30 to which a large force is applied when the external electric wire 21 is tightened is thicker than when iron is used. With this increase in thickness, the square frame 30
Between the outer surface on the side of the second exhaust path 15 and the inner wall of the third chamber 130 (under the square frame 30 in FIG. 6), and the second exhaust path of the square frame 30 At least one of the two outer surfaces following the outer surface on the 15th side and the housing third chamber 1
Between the inner wall 30 and the inner wall 30 (in FIG. 6, the front and rear sides of the square frame 30).
It becomes difficult to provide the first exhaust path 16 in any of the above.

In such a case, as in the present embodiment, the first exhaust path 16 is connected to the screw 29 of the square frame 30.
If the first exhaust path 16 is provided so as to communicate with the outside of the housing 20 through the gap between the outer surface on the insertion side and the inner wall of the housing third chamber 130, the end of the first arc runner 11 on the arc extinguishing device 10 side is provided. It can be provided near the part.

In the fourth embodiment shown in FIG. 5, the structure of the terminal 13 shown in FIG. 8 of this embodiment may be adopted.

Embodiment 6 FIG. FIG. 9 is a sectional view showing a configuration of a circuit breaker according to Embodiment 6 of the present invention. In FIG. 9, reference numeral 23 denotes a cooling plate located between the communication port 42 and the opening / closing mechanism 5 for circulating gas for cooling. Reference numeral 41 denotes an induction partition wall, which guides the gas flowing from the first housing 25 through the communication port 42 together with the heat-resistant cover 33 to the cooling plate 23 while isolating the gas from the opening / closing mechanism 5 and the overcurrent trip device 6. To form a guiding member. B4 is an arrow indicating the flow of the high-temperature gas flowing into the second housing (upper space) 24.

In the fourth embodiment shown in FIG. 5, the high-temperature gas flowing into the second housing (upper space) 24 passes through the space (the third housing 130 of the housing) in which the screw 29 is stored. As shown in FIG. 9, high-temperature gas flowing into the upper space 24 from the housing first chamber (lower space) 25 is supplied to the guide member (heat-resistant member). It may be configured such that the gas is guided to the cooling plate 23 by the conductive cover 33 and the guide partition 41), and the high-temperature gas is processed in the housing.

In the present embodiment, the cooling plate 23 in which a plurality of perforated metal plates are combined is provided between the communication port 42 and the opening / closing mechanism 5, and the high temperature of the high temperature flowing into the upper space 24 from the communication port 42. The gas is cooled by the cooling plate 23 without being exhausted to the outside of the housing 20, and the melt contained in the high-temperature gas is adsorbed by the cooling plate 23. Therefore, the gas flowing into the opening / closing mechanism 5 does not damage the mechanism. In addition, since the high-temperature gas is not exhausted to the outside of the housing 20 on the upper space 24 side, the safety of the operator who manually operates the handle 7 is enhanced.

In the example shown in FIG. 9, high-temperature gas is not exhausted on the upper space 24 side.
Exhaust configuration through the space (housing third chamber 130) containing the screw 29 from the upper space 24 shown in FIGS. 5 and 6, and exhaust configuration using the cooling plate 23 shown in FIG. May be combined. Due to this combination, due to problems such as arc space and safety to the operator, only the exhaust configuration passing from the upper space 24 through the space containing the screw 29 can provide a sufficient exhaust flow rate to the outside of the housing 20. Even in the case where it is not possible to secure the arc extinguishing device 10 of the first arc runner 11 by flowing a high-temperature gas to the cooling plate 23 side.
Exhaust efficiency near the side end can be sufficiently increased.

In FIG. 9, by tightening the same screws 29 as those described in the first to fourth embodiments as the first terminals 13, the square frame 30 is opposite to the side on which the second exhaust path 15 is installed. Although the state in which the screw 29 is not tightened is shown using the structure that moves in the direction, the structure in which the screw 29 similar to that shown in the fifth embodiment moves to the second exhaust path 15 installation side It is needless to say that may be used.

The cooling plate 23 is not limited to a combination of a plurality of perforated metal plates, but is a device that captures a melt contained in a high-temperature gas accompanying an arc and cools and passes the high-temperature gas. Any material may be used, for example, a porous material or a fibrous material may be used.

[0060]

As described above, according to the present invention, a fixed contact, a movable contact opposed to the fixed contact and arranged freely in the housing, and the movable contact An opening / closing mechanism for driving the contact; an overcurrent trip device for operating the opening / closing mechanism in response to the overcurrent to release the movable contact; and an arc generated when the movable contact is opened. An arc extinguishing device that divides and extinguishes the arc by an arc extinguishing plate, and a pair of first and second arc runners that guide the arc from the pair of contacts including the fixed contact and the movable contact to the arc extinguishing device. In the circuit breaker provided with the first and second arc runners, first and second exhaust passages respectively communicating with the outside of the housing are disposed near the arc extinguishing device side ends of the first and second arc runners, and the overcurrent trip is performed. Is the device and the opening / closing mechanism an arc guided by the arc extinguishing device? The overcurrent tripping device and the switching mechanism are exposed to the high-temperature gas associated with the arc even when the breaking capacity is increased or the size is reduced without increasing the size because the isolation member is provided to isolate the generated gas flow. Without this, it is possible to prevent pressure imbalance in the first arc runner and the second arc runner in the vicinity of the arc extinguishing device side end, thereby effectively utilizing the arc extinguishing plate to cut off the arc. Reliable and high breaking performance can be compatible.

Further, the first chamber for housing the arc extinguishing device disposed between the pair of first and second arc runners, and the first arc runner disposed on the side opposite to the arc extinguishing device arrangement side. A housing second chamber for accommodating the current trip device and the opening / closing mechanism, and a side opposite to the contact pair installation side of the arc extinguishing device, disposed adjacent to the housing first and second chambers;
A third housing for housing a square frame, into which a screw is attached and which connects an external electric wire inserted into the frame from outside the housing to the conductor end from one of the contact pairs by fastening the screw; The first exhaust path is provided so as to communicate with the outside of the housing through a gap between the outer surface of the square frame and the inner wall of the third housing of the housing, and the second exhaust passage is provided in the housing. Since it is provided between the three chambers and the second arc runner, the first exhaust path can be configured without exposing the external electric wires and screws inside the square frame to the high-temperature gas accompanying the arc, and the outside by the high-temperature gas can be formed. Damage and fusion of the wires and the like can be prevented.

Further, the screw is mounted so as to be screwed into the square frame from the side opposite to the side on which the second exhaust path is provided, and the first exhaust path is formed by the above-mentioned square frame. Since it was provided so as to communicate with the outside of the housing through a gap between the inner surface of the housing third chamber and at least one of the outer surface on the second exhaust path side and the following two outer surfaces, The first exhaust path can be configured without exposing the threads and screw heads outside the square frame in addition to the external electric wires and screws inside the square frame, to the high-temperature gas accompanying the arc, Damage and fusion of the external electric wires and screws due to the high-temperature gas can be prevented.

Further, since a communication path for connecting the first exhaust path and the second exhaust path in the middle of each exhaust path is provided,
An imbalance in pressure near the arc extinguishing device side end between the arc runner and the second arc runner can be more reliably prevented.

Further, the screw is mounted so as to be screwed into the square frame from the side opposite to the side on which the second exhaust path is provided, and the first exhaust path is formed in the square frame. Since it was provided so as to communicate with the outside of the housing through the gap between the outer surface on the screw insertion side and the inner wall of the housing third chamber, in a state where the screw was tightened and the external electric wire was connected to the conductor end, The outer surface on the second exhaust path side of the square frame and the two outer surfaces following the outer surface and the housing third
Even if the gap with the inner wall of the chamber is narrow, the first exhaust
It can be provided near the arc extinguisher side end of the arcrunner, and can constitute the first exhaust path without exposing the external electric wires and screws inside the square frame to the high-temperature gas accompanying the arc, Damage and fusion of the external electric wire and the like due to the high-temperature gas can be prevented.

Further, a housing fourth chamber isolated from the screw is provided between the screw head and the inner wall of the housing third chamber.
Since it was provided so as to communicate with the outside of the housing through the housing fourth chamber, in addition to the external electric wires and screws inside the square frame, a screw thread outside the square frame and The first exhaust path can be configured without exposing the screw head to the high-temperature gas accompanying the arc, and damage and fusion of the external electric wire and the screw due to the high-temperature gas can be prevented.

Also, a fixed contact, a movable contact opposed to the fixed contact so as to be able to freely contact and separate within the housing, an opening / closing mechanism for driving the movable contact, and an overcurrent An overcurrent tripping device that operates the opening / closing mechanism in response to open the movable contact and an arc generated when the movable contact is opened is divided and extinguished by a plurality of arc extinguishing plates. In a circuit breaker provided with an arc extinguishing device and a pair of first and second arc runners for guiding the arc from the pair of contacts to the arc extinguishing device, the pair of first and second arc runners is provided.
A first housing for accommodating the arc extinguishing device disposed between the arc runners, and a housing disposed on a side of the first arc runner opposite to the arc extinguishing device arrangement side and accommodating the overcurrent trip device and the opening / closing mechanism; A body second chamber, an exhaust passage arranged near the arc extinguishing device side end of the second arc runner and communicating with the outside of the housing, and the housing first chamber and the housing second connected to the first arc runner. A communication port for communicating near the arc extinguishing device side end,
A cooling plate that is located between the communication port and the opening / closing mechanism or the overcurrent trip device and that cools the gas by flowing the gas; and that opens and closes the gas flowing from the first housing through the communication port. Since the mechanism and the guide member for guiding the cooling plate while being isolated from the overcurrent tripping device are provided, the overcurrent tripping device can be used even if the breaking capacity is increased or made compact without increasing the size. And preventing the opening and closing mechanism from being exposed to the high-temperature gas accompanying the arc, thereby preventing imbalance in pressure near the arc extinguishing device side end between the first arc runner and the second arc runner, thereby effectively utilizing the arc extinguishing plate. Since the arc can be divided, it is possible to achieve both the reliability of the breaking operation a plurality of times and high breaking performance.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a circuit breaker according to Embodiment 1 of the present invention.

FIG. 2 is a sectional view taken along line CC of FIG.

FIG. 3 is a sectional view illustrating a configuration of a main part of a circuit breaker according to a second embodiment of the present invention.

FIG. 4 is a sectional view showing a configuration of a circuit breaker according to a third embodiment of the present invention.

FIG. 5 is a sectional view showing a configuration of a circuit breaker according to a fourth embodiment of the present invention.

FIG. 6 is a sectional view showing a configuration of a circuit breaker according to a fifth embodiment of the present invention.

FIG. 7 is an exploded perspective view showing the vicinity of a screw operation opening in FIG. 6;

FIG. 8 is a perspective view showing the vicinity of a square frame in FIG. 6;

FIG. 9 is a sectional view illustrating a configuration of a circuit breaker according to a sixth embodiment of the present invention.

FIG. 10 is a cross-sectional view showing a configuration of a conventional circuit breaker.

FIG. 11 is a cross-sectional view showing a configuration of another conventional circuit breaker.

12 is a cross-sectional view showing a configuration of a circuit breaker that can be considered as an improved example of the circuit breaker shown in FIG.

FIG. 13 is a sectional view taken along line CC of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 movable contact, 2 movable contact, 3 fixed contact, 4 fixed contact, 5 opening / closing mechanism, 6 overcurrent trip device, 7
Handle, 8 arc extinguishing plate, 9 arc extinguishing side plate, 10 arc extinguishing device, 11, 12, first and second arc runners, 13, 14
1st, 2nd terminal, 15 2nd exhaust path, 16 1st exhaust path, 17 2nd exhaust port, 18 1st exhaust port, 19 flexible conductor, 20 housing, 21 external electric wire, 22 tubular insulating cap , 23 cooling plate, 24 housing second chamber,
25 first housing chamber, 26 partition wall, 27 current plate, 29
Screw, 30 square frame, 30a female screw hole, 31 conductor end, 32 communication path, 33 heat resistant cover, 34 partition, 35 opening, 36 exhaust port, 37 screw operation opening, 38 housing 4 rooms, 39 partitions, 41 induction partitions,
42 communication port, 130 housing third room, 150 exhaust path,
170 exhaust port, 261 communication port.

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Tatsunori Ikeda             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo 3             Rishi Electric Co., Ltd. F term (reference) 5G027 AA03 BB05 BB09 BC03 BC07                       BC11 BC16                 5G030 DA02 DB01 DD02 DE03 YY07

Claims (7)

[Claims] 1. A fixed contact, a movable contact opposed to and fixed to the fixed contact inside the housing, an opening / closing mechanism for driving the movable contact, and an overcurrent An overcurrent tripping device that operates the opening / closing mechanism in response to open the movable contact and an arc generated when the movable contact is opened is divided and extinguished by a plurality of arc extinguishing plates. An arc extinguishing device, and a pair of first exciters for guiding the arc from the contact pair including the fixed contact and the movable contact to the arc extinguishing device.
And a second arc runner, wherein first and second exhaust paths communicating with the outside of the housing are disposed near the arc extinguishing device side ends of the first and second arc runners, respectively, and A circuit breaker comprising: an isolating member for isolating the overcurrent tripping device and the switching mechanism from a gas flow generated from an arc guided to the arc extinguishing device. 2. A first housing for accommodating an arc extinguishing device disposed between a pair of first and second arc runners, and a housing arranged on a side of the first arc runner opposite to the arc extinguishing device arrangement side. A second housing for accommodating the current trip device and the switching mechanism
The chamber and the arc extinguishing device are arranged adjacent to the first and second chambers on the side opposite to the contact pair installation side of the arc extinguishing device. A third housing for accommodating a square frame that connects the external electric wire inserted into the frame to the conductor end from one of the contactor pairs;
The exhaust path is provided so as to communicate with the outside of the housing through a gap between the outer surface of the square frame and the inner wall of the housing third chamber, and the second exhaust path is provided between the housing third chamber and the second housing. 2. The circuit breaker according to claim 1, wherein the circuit breaker is provided between the arcrunners. 3. The screw is mounted so as to be screwed into the square frame from the side opposite to the second exhaust path installation side,
The first exhaust passage passes through a gap between at least one of the outer surface on the second exhaust passage side of the square frame and the following two outer surfaces and the inner wall of the housing third chamber. The circuit breaker according to claim 2, wherein the circuit breaker is provided so as to communicate with the outside of the housing. 4. The circuit breaker according to claim 3, further comprising a communication path that connects the first exhaust path and the second exhaust path in the respective exhaust paths. 5. The screw is mounted so as to be screwed into a square frame from the side opposite to the second exhaust path installation side,
The first exhaust path is provided so as to communicate with the outside of the housing through a gap between an outer surface of the square frame on the screw insertion side and an inner wall of the housing third chamber. The circuit breaker according to claim 2. 6. A housing fourth chamber isolated from the screw between the screw head and the inner wall of the housing third chamber, wherein the first exhaust path passes through the housing fourth chamber and is external to the housing. The circuit breaker according to claim 5, wherein the circuit breaker is provided so as to communicate with the circuit breaker. 7. A fixed contact, a movable contact opposed to and fixed to the fixed contact inside the housing, an opening / closing mechanism for driving the movable contact, and an overcurrent An overcurrent tripping device that operates the opening / closing mechanism in response to open the movable contact and an arc generated when the movable contact is opened is divided and extinguished by a plurality of arc extinguishing plates. In a circuit breaker including an arc extinguishing device and a pair of first and second arc runners for guiding the arc from the pair of contacts to the arc extinguishing device, the circuit breaker is disposed between the pair of first and second arc runners. A first housing for housing the arc extinguishing device, and a second housing for housing the overcurrent tripping device and the opening / closing mechanism which are arranged on a side of the first arc runner opposite to the arc extinguishing device arrangement side. Is disposed near the arc extinguishing device side end of the second arc runner. An exhaust passage communicating with the outside of the housing, a communication port for connecting the first housing and the second housing in the vicinity of the end of the first arc runner on the arc extinguishing device side, and the communication port and the opening and closing; A cooling plate which is located between a mechanism and an overcurrent tripping device and which circulates and cools a gas, and a gas which flows from the first chamber through the communication port through the opening / closing mechanism and the overcurrent tripping device A circuit breaker comprising: a guide member that guides the cooling plate while being isolated from the device.