JP2007214050A - Arc extinguishing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an arc extinguishing device in which current limiting performance has been improved. <P>SOLUTION: This is the arc extinguishing device in which an arc A formed when a fixed contact 16 and a movable contact 19 are contact parted, is made to run in the tip direction Z of a contact supporting piece 13 from the fixed contact point 16 by a magnetic field generated by a driving coil part 14, and an arc running face 33 of the contact supporting piece 13 is gradually separated from an extended line L1 of a contact adhering face 31 of the contact supporting piece 13 as it goes toward the tip side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an arc extinguishing device applied to a circuit breaker or the like.

  Patent Documents 1 and 2 disclose an arc extinguishing device that extinguishes an arc generated when a circuit breaker or the like is interrupted. This type of arc extinguishing device includes a fixed contact, a movable contact, a yoke, a cooling member, and a travel plate.

  The fixed contact is formed of a conductive material, has a rectangular terminal at one end, a contact support piece that extends from the other end to the vicinity of the terminal, and a fixed contact fixed to the vicinity of the tip, and both sides of the fixed contact And a driving coil portion that connects the one end portion and the other end portion and generates magnetic flux by energization.

  The movable contact is made of a conductive material, has a movable contact that contacts the fixed contact, and is configured to be rotatable so that the movable contact can be moved toward and away from the fixed contact. A contact portion is constituted by the fixed contact and the movable contact. When an overcurrent passes through the electric circuit, the movable contact is rotated by the overcurrent detection circuit so that the contact portion is opened.

  The yoke is formed of a magnetic material, has a pair of opposing pieces and a connecting piece that connects the opposing pieces, and is formed in a substantially U shape so as to straddle both drive coil portions. Magnetic flux generated by the drive coil portion passes through this yoke.

  The cooling member is formed of an insulating material that generates pyrolysis gas when heated, and is provided along the inner surface of the yoke. The cooling member takes heat from the arc generated between the two contacts when the contact is opened. It generates cracked gas.

  The travel plate is made of a conductive material having a resistance higher than that of the contact support piece, and allows the arc to travel from the tip of the contact support piece to travel further from the fixed contact. Protrusively provided.

The arc extinguishing apparatus having such a configuration operates as follows. When the contact portion is opened, an arc is generated between the fixed contact and the movable contact. This arc travels toward the front end side of the contact support piece by Lorentz force generated between the arc and a magnetic field generated around the drive coil portion. When the arc reaches the tip of the contact support piece, it moves from the contact support piece to the travel plate and travels on the travel plate. When the arc travels in this way, the arc length is extended, so that the arc voltage increases. At the same time, since the cooling member absorbs the heat of the arc and generates pyrolysis gas, the arc is cooled. Such arc elongation and arc cooling rapidly interrupts the arc. That is, the arc is extinguished rapidly.
JP-A-9-17316 JP-A-7-220611

  Such an arc extinguishing apparatus is required to be small and have a high capacity. When the current is increased, the amount of gas generated from the cooling member increases, and the internal pressure of the arc extinguishing apparatus increases. In such a case, it is necessary to increase the pressure resistance of each component of the arc extinguishing device, which increases the manufacturing cost.

  Since the amount of gas generated from the cooling member increases as the arc current increases, it is effective to improve the current limiting performance and reduce the arc current.

  The present invention has been made in view of such a reason, and an object of the present invention is to provide an arc extinguishing device with improved current limiting performance.

  In view of this, the present inventor has paid attention to the fact that, in order to improve the current limiting performance, it is effective to increase the arc voltage more quickly by extending the arc more quickly or to cool the arc efficiently.

The invention according to claim 1 is a terminal portion provided at one end portion, a contact support piece extending from the other end portion to the vicinity of the terminal portion and having a fixed contact fixed in the vicinity of a longitudinal tip thereof, and the contact point A fixed contact having a drive coil portion that is connected to the one end and the other end on both sides of the support piece and generates a magnetic flux by energization; a movable contact that contacts the fixed contact; and the fixed contact; A movable contact that allows the movable contact to be brought into and out of contact with the movable contact, and an arc generated when the movable contact is opened from the fixed contact by the magnetic field generated by the drive coil unit from the fixed contact. An arc extinguishing device that travels in the tip direction of the contact support piece,
The arc running surface of the contact support piece is gradually separated from the extension line of the contact fixing surface of the contact support piece as it goes to the tip side.

  In the first aspect, the arc running surface of the contact support piece may be stepped, inclined, partially inclined, or a combination thereof.

  Invention of Claim 2 is the arc-extinguishing apparatus of Claim 1, Comprising: The front end side rather than the fixed contact of the said contact support piece is formed thinly gradually toward the front end, It is characterized by the above-mentioned. .

  A third aspect of the present invention is the arc extinguishing device according to the first aspect, wherein the tip end side of the contact support piece is bent toward the opposite side to the movable contact point. And

According to a fourth aspect of the present invention, there is provided a terminal portion provided at one end portion, a contact support piece extending from the other end portion to the vicinity of the terminal portion and having a fixed contact fixed in the vicinity of a longitudinal end thereof, and the contact point A fixed contact having a drive coil portion that is connected to the one end and the other end on both sides of the support piece and generates a magnetic flux by energization; a movable contact that contacts the fixed contact; and the fixed contact; Conductive travel that is disposed in contact with the back surface of the surface of the contact support piece on which the fixed contact of the contact support piece is fixed and protrudes from the front end of the contact support piece. And an arc extinguishing device for causing an arc generated when the movable contact is opened from the fixed contact to travel from the fixed contact toward the tip of the contact support piece by a magnetic field generated by the drive coil unit. Because
The travel plate is formed in a crank shape at a position close to the tip of the contact support piece, thereby forming an ascending step from the arc travel surface of the contact support piece to the arc travel surface of the travel plate. Features.

According to a fifth aspect of the present invention, there is provided a terminal portion provided at one end portion, a contact support piece extending from the other end portion to the vicinity of the terminal portion and having a fixed contact fixed in the vicinity of a longitudinal end thereof, and the contact point A fixed contact having a drive coil portion that is connected to the one end and the other end on both sides of the support piece and generates a magnetic flux by energization; a movable contact that contacts the fixed contact; and the fixed contact; Conductive travel that is disposed in contact with the back surface of the surface of the contact support piece on which the fixed contact of the contact support piece is fixed and protrudes from the front end of the contact support piece. And an arc extinguishing device for causing an arc generated when the movable contact is opened from the fixed contact to travel from the fixed contact toward the tip of the contact support piece by a magnetic field generated by the drive coil unit. Because
The travel plate is provided with an opening window, and a tip of the contact support piece is located on a side farther from the movable contact than the travel plate by being inserted from the opening window of the travel plate.

According to a sixth aspect of the present invention, there is provided a terminal portion provided at one end portion, a contact support piece extending from the other end portion to the vicinity of the terminal portion and having a fixed contact fixed in the vicinity of a longitudinal end thereof, and the contact point A fixed contact having a drive coil portion that is connected to the one end and the other end on both sides of the support piece and generates a magnetic flux by energization; a movable contact that contacts the fixed contact; and the fixed contact; Conductive travel that is disposed in contact with the back surface of the surface of the contact support piece on which the fixed contact of the contact support piece is fixed and protrudes from the front end of the contact support piece. And an arc extinguishing device for causing an arc generated when the movable contact is opened from the fixed contact to travel from the fixed contact toward the tip of the contact support piece by a magnetic field generated by the drive coil unit. Because
The arc travel surface of the travel plate has a portion that is separated from an extension line of the contact fixing surface as the distance from the fixed contact increases.

The invention according to claim 7 includes a terminal portion provided at one end, a contact support piece extending from the other end to the vicinity of the terminal portion, and having a fixed contact fixed in the vicinity of a longitudinal end thereof, and the contact A fixed contact having a drive coil portion that is connected to the one end and the other end on both sides of the support piece and generates a magnetic flux by energization; a movable contact that contacts the fixed contact; and the fixed contact; Conductive travel that is disposed in contact with the back surface of the surface of the contact support piece on which the fixed contact of the contact support piece is fixed and protrudes from the front end of the contact support piece. And an arc extinguishing device for causing an arc generated when the movable contact is opened from the fixed contact to travel from the fixed contact toward the tip of the contact support piece by a magnetic field generated by the drive coil unit. Because
The traveling plate is characterized in that a tip end portion thereof is wound back in a substantially C shape toward the movable contact side.

  The invention according to claim 8 is the arc-extinguishing device according to claim 7, wherein a terminal portion on the movable contact side of the distal end portion of the traveling plate is wider than the base end side. To do.

  Invention of Claim 9 is an arc-extinguishing apparatus of Claim 7, Comprising: A width | variety is smaller than the said terminal part to the base end side rather than the terminal part by the side of the movable contact of the front-end | tip part of the said travel plate A constricted portion is provided.

  Invention of Claim 10 is an arc-extinguishing apparatus of any one of Claims 7-9, Comprising: In the terminal part by the side of the movable contact of the front-end | tip part of the said travel board, it is in the traveling direction of the said arc. An extending slit-shaped notch is provided.

  According to the first aspect of the present invention, since the arc running surface of the contact support piece gradually moves away from the extension line of the contact fixing surface as it goes to the tip side, the arc running surface of the contact support piece becomes the contact fixing surface. As compared with the conventional structure set as the extension line, the arc is further extended, the arc voltage is further increased, and the current limiting performance is improved. Therefore, the amount of pyrolysis gas generated from the cooling member is reduced, and an excessive pressure increase in the arc extinguishing device can be avoided.

  In the first aspect, the arc running surface of the contact support piece may be stepped, inclined, partially inclined, or a combination thereof.

  According to the second aspect of the invention, the structure of the first aspect can be easily manufactured by forming the tip side of the contact support piece from the fixed contact point gradually toward the tip. Therefore, the manufacturing cost can be reduced.

  For example, in a structure including a traveling plate that is arranged in contact with the back surface of the contact support piece on which the fixed contact is fixed and protrudes from the tip of the contact support piece, the arc of the contact support piece at the tip of the contact support piece. Since the level difference between the traveling surface and the arc traveling surface of the traveling plate is reduced, the arc easily transfers from the arc traveling surface of the contact support piece to the arc traveling surface of the traveling plate, and the arc stays at the tip of the contact supporting piece. Since the time is shortened, the arc current decreasing rate is increased, and the current limiting performance is further improved.

  According to the third aspect of the invention, the structure of the first aspect can be easily manufactured by bending the tip side of the contact support piece from the fixed contact toward the opposite side of the movable contact. Therefore, the manufacturing cost can be reduced.

  According to the fourth aspect of the present invention, the travel plate is formed in a crank shape at a position close to the tip of the contact support piece, so that the arc travel surface of the contact support piece changes to the arc travel surface of the travel plate. It is an ascending step. Therefore, compared with the conventional structure in which the tip of the contact support piece has a step down from the arc running surface of the contact support piece to the arc running surface of the running plate, the arc travels from the arc running surface of the contact support piece to the arc running surface of the running plate. Since the residence time when the arc commutates from the contact support piece to the traveling plate is shortened, the extension of the arc can be promoted.

  According to the fifth aspect of the present invention, the traveling plate includes the opening window, and the tip of the contact support piece is located on the side farther from the moving contact than the traveling plate by being squeezed from the opening window of the traveling plate. Therefore, compared to the conventional structure in which the tip of the contact support piece has a downward step from the arc travel surface of the contact support piece to the arc travel surface of the travel plate, the arc travel of the contact support piece is performed at the periphery of the opening window of the travel plate. Since the uphill step from the plate to the arc travel surface of the travel plate, the arc quickly transfers from the arc travel surface of the contact support piece to the arc travel surface of the travel plate, and the dwell time of the arc at the tip of the contact support piece is shortened , Can promote arc elongation.

  According to the sixth aspect of the present invention, the arc travel surface of the travel plate has an inclined surface that moves away from the extension line of the contact fixing surface as the distance from the fixed contact increases, so that the arc travels on the arc travel surface of the travel plate. When traveling, the arc length can be further extended, that is, arc extension can be promoted, so that the current limiting performance is improved.

  According to the invention described in claim 7, since the traveling plate has its tip end portion wound back in a substantially C shape on the movable contact side, when the arc travels on the arc traveling surface of the traveling plate, This arc comes close to the terminal portion on the movable contact side at the tip of the traveling plate that has been rolled back in a C-shape. At this time, since this terminal part acts as a heat absorption part that receives the heat of the arc, the arc is cooled, whereby the reduction of the arc current is promoted, and the current limiting performance is improved. Thereby, the amount of pyrolysis gas generated from the cooling member is reduced, and an excessive pressure increase in the arc extinguishing device can be avoided.

  According to the invention described in claim 8, in addition to the effect of the invention described in claim 7, the terminal part (heat absorption part) on the movable contact side of the distal end part of the traveling plate is wider than the base end side. As a result, the heat capacity increases and the amount of arc cooling increases. Thereby, the current limiting performance is further improved.

  According to the ninth aspect of the invention, in addition to the effect of the seventh aspect of the invention, the width of the distal end portion of the traveling plate is smaller on the base end side than the terminal portion on the movable contact side than the terminal portion. Since the constricted part is provided, the heat received by the terminal part (heat-absorbing part) is less likely to flow to the base end side due to the constriction effect, and heat tends to accumulate in the terminal part. It is expected that the arc is rapidly cooled by the latent heat of vaporization.

  According to the invention described in claim 10, in addition to the effect of the invention described in any one of claims 7-9, the terminal portion on the movable contact side of the tip portion of the traveling plate extends in the arc traveling direction. Since the slit-shaped notch is provided, the traveling arc can finally be passed through the slit-shaped notch. When the arc penetrates the slit-shaped notch, the arc can travel to a position farther from the movable contact, and the area that can receive the heat of the arc so as to surround the arc becomes wide. Therefore, the arc voltage increase effect and arc cooling effect due to arc extension can be obtained at the same time, and the current limiting performance is further improved.

  In the present specification, the “contact fixing surface of the contact support piece” means that the fixed contact is fixed on the surface of the contact support piece on which the fixed contact is fixed (the upper surface of the contact support piece in the following embodiment). The part that was done. Further, “the arc running surface of the contact support piece” means a portion (contact point) to which the fixed contact is fixed out of the surface of the contact support piece to which the fixed contact is fixed (in the following embodiment, the upper surface of the contact support piece). The portion on the tip side of the contact support piece from the fixed surface) is the portion where the arc travels when the movable contact is opened from the fixed contact. Further, the “arc travel surface of the travel plate” refers to the tip of the contact support piece of the travel plate that is on the same side as the arc travel surface (the upper surface of the travel plate in the following embodiment) than the tip of the contact support piece. The part that protrudes to the side.

  Embodiments of the present invention will be described below with reference to the drawings.

1st Embodiment First, the arc-extinguishing apparatus of 1st Embodiment is demonstrated, referring FIGS.

  FIG. 1 is a side view including a partially broken portion showing an outline of a circuit breaker to which an arc extinguishing device of the present embodiment is applied, FIG. 2 is an exploded perspective view of the arc extinguishing device of the present embodiment, and FIG. FIG. 4 is a diagram for explaining the operation of the arc extinguishing device and shows a state immediately after the opening of the movable contact. FIG. 5 is an operation explanatory diagram for the arc extinguishing device and the movable contact is greatly opened. It is a figure which shows a state. The yoke is not shown in all drawings after FIG.

  The arc-extinguishing apparatus 10 of this embodiment is integrated in the circuit breaker 1 for earth-leakage interruption as shown in FIG. The circuit breaker 1 includes an insulating housing 3 including a container-shaped housing body 3a and a cover 3b that closes the opening end of the housing body 3a. In addition to the arc extinguishing device 10, the circuit breaker 1 includes an overcurrent. An overcurrent detection device (not shown) and other components for opening a contact portion made up of a fixed contact and a movable contact when an electric current flows are arranged. The arc extinguishing device according to the present invention is not limited to a circuit breaker for earth leakage interruption, and can be used for various devices such as a circuit breaker for wiring and an electromagnetic contactor.

  The arc-extinguishing apparatus 10 of this embodiment includes a fixed contact 11, a movable contact 18, a yoke 20, a cooling member 23, and a travel plate 24 as shown in FIGS. The fixed contact 11 is fixed to the housing main body 3a by a terminal screw 15 described later (see FIG. 1), and the movable contact 18 is rotatably supported in the housing 3 by a support structure (not shown). The yoke 20 and the cooling member 23 are fixed so as to be pressed against the fixed contact 11 by a cover 3b fitted and fastened to the housing body 3a in a temporarily assembled state (see FIG. 1).

  The fixed contact 11 is formed by bending a plate-shaped conductive material, and has a substantially rectangular terminal portion 12 provided at one end portion, and a substantially rectangular contact support extending from the other end portion to the vicinity of the terminal portion 12. It comprises a piece 13 and a drive coil part 14 that connects between one end and the other end.

  A terminal screw 15 for connecting an external electric wire is screwed to the terminal portion 12 in the vicinity of the tip 12a.

  The contact support piece 13 is provided substantially in parallel with the terminal portion 12 at a position different in height from the terminal portion 12 in the vertical direction and at a position slightly apart in the longitudinal direction. A fixed contact 16 is fixed to the top surface of the contact support piece 13 in the vicinity of the tip 13a of the contact support piece.

  The drive coil portion 14 is configured as a pair of long plates that connect the base end 12 b of the terminal portion 12 and the base end 13 b of the contact support piece 13 on both sides of the contact support piece 13. In the vicinity, it is configured to have a portion curved in a substantially four-half arc shape.

  The movable contact 18 is a conductive material and is rotatably supported by a support structure (not shown) in the housing 3 of the circuit breaker. A movable contact 19 that contacts and separates from the fixed contact 16 is provided on the lower surface of the movable contact 18 on the rotating tip side. The movable contact 19 and the fixed contact 16 constitute a contact portion, and this contact portion is interposed in the middle of the electric circuit formed between the power source and the load. The movable contact 18 is rotationally driven so that the contact portion is opened by an overcurrent detection device (not shown) when an overcurrent passes through the electric circuit.

  The yoke 20 is made of a magnetic material and is provided above the drive coil portion 14 so as to straddle both the drive coil portions 14. The yoke 20 includes a pair of opposed pieces 20a and 20a disposed on both sides of the movable contact 18, and a connecting piece 20b that magnetically shorts the upper ends of the opposed pieces 20a and 20a. It is formed in a substantially U-shape that opens downward. When a current flows through the drive coil unit 14, a magnetic field is generated around the drive coil unit 14, and the magnetic flux passes through the pieces 20a, 20b, and 20a along the U-shape of the yoke 20. In the vicinity of the contact portion, this magnetic flux straddles between the opposing opposing pieces 20a, 20a and passes in the direction opposite to the direction of the magnetic flux passing through the connecting piece 20b.

  A plurality of rectangular grid pieces 20c project from the opposing pieces 20a and 20a at positions where the opening on the terminal portion 12 side of the yoke 20 is closed. Each of the grid pieces 20c is arranged with a plurality of gaps in a plurality of stages in the vertical direction, and the arc gas can pass through the gaps.

  The cooling member 23 is disposed on the upper surface of the fixed contact 11 in a state of covering the inner peripheral surface of the yoke 20 so as to be exposed to the arc A generated between the two contacts. The cooling member 23 is formed of an insulating material, and as this insulating material, a material that generates pyrolysis gas by arc heat, for example, a polyamide resin or the like is used. That is, the arc A is cooled by the pyrolysis gas, and the arc is quickly extinguished.

  The cooling member 23 projects from a U-shaped main body portion 23a provided in a substantially U shape along the inner peripheral surface of the yoke 20 to cover the inner peripheral surface of the yoke 20, and from the lower end of the main body portion 23a. Partition pieces 23b, 23b for partitioning between the contact support piece 13 and the drive coil portion 14, cover pieces 23c, 23c protruding outward from the side surface of the main body portion 23a and covering the upper surface of the drive coil portion 14, and the main body portion A cover piece 23d that protrudes inward from the side surface from 23a and covers the base end 13b side of the fixed contact 16 of the contact support piece 13, and a base end 12b of the terminal portion 12 that protrudes inward from the main body 23a. That is, it has a covering piece 23e that covers (the end portion on the contact support piece 13 side of the terminal portion 12). Therefore, the arc A generated when the contact portion is opened is prevented from shifting to the terminal portion 12, the drive coil portion 14, and the like.

  The travel plate 24 is made of a conductive material having a resistance higher than that of the contact support piece 13 so that the arc A can run out of the tip 13 a of the contact support piece 13. The travel plate 24 has a base end 24b attached to the surface of the contact support piece 13 opposite to the fixed contact 16, that is, the lower surface of the contact support piece 13, and the front end 24a is contacted from the base end 24b. The contact piece 13 is provided so as to protrude further in the longitudinal direction of the support piece 13 than the tip 13 a of the contact support piece 13. That is, the front end side 24 a of the travel plate 24 extends toward the terminal portion 12 side from the front end 13 a of the contact support piece 13 in the longitudinal direction of the contact support piece 13. The upper surface of the leading end side 24a of the travel plate 24 becomes an arc travel surface 25 on which the arc A travels. A pair of opposing pieces 24c and 24c are projected from both sides of the base end portion 24b of the travel plate 24. In the assembled state, the opposing pieces 24c and 24c are fitted to the partition pieces 23b and 23b of the cooling member 23 from the outside. is doing.

  In the present embodiment, the arc running surface 33 of the contact support piece 13 gradually increases from the extension line L1 of the contact fixing surface 31 toward the side opposite to the movable contact 19 (in the direction away from the movable contact 19) as it goes to the tip side. It has the inclined surface 33a which leaves | separates. The inclined surface 33a is formed by gradually forming a portion on the tip side of the contact support piece 13 toward the tip 13a so as to be thin.

  Next, operation | movement of the arc-extinguishing apparatus of this embodiment is demonstrated based on FIGS.

  When an overcurrent flows in the closed state of the contact portion shown in FIG. 3, the movable contact 18 is rotationally driven by an overcurrent detection device (not shown), and the fixed contact 16 to the movable contact 19 as shown in FIG. Is opened, an arc A is generated between both contacts 16 and 19. The movable contact 18 continues to rotate and the arc A is extended. The generated arc A is driven by the magnetic field generated by the drive coil unit 14 and travels from the fixed contact 16 toward the tip end side (arrow Z direction) of the contact support piece 13 as shown in FIG. When the arc A reaches the front end 13a of the contact support piece 13, the travel plate 24 is transferred, and the travel plate 24 further extends while traveling in the front end direction (arrow Z direction).

  The arc voltage is increased by the extension of the arc A, and the arc A is cooled by the cooling member 23 taking heat of the arc A and generating pyrolysis gas. Thereby, the arc current is attenuated, the arc A is finally extinguished, and the electric circuit is interrupted. The arc gas generated by the arc extinguishing is discharged out of the housing 3 through a gap (ventilation port) between the plurality of grid pieces 20 c and an exhaust port (not shown) provided in the housing 3.

  Here, in order for the arc A to travel on the inclined surface 33a of the arc traveling surface 33 of the contact support piece 13, the arc voltage is further increased because the arc is further extended as compared with a structure without such an inclined surface. As a result, the current limiting performance is improved. As a result, the amount of pyrolysis gas generated from the cooling member 23 is reduced, and an excessive pressure increase in the arc extinguishing apparatus 10 can be avoided.

  Next, the effects of the arc extinguishing apparatus 10 of this embodiment will be listed.

  According to the arc extinguishing apparatus 10 of the present embodiment, the arc running surface 33 of the contact support piece 13 is structured to gradually move away from the extension line L1 of the contact fixing surface 31 as it goes to the tip side. Compared with the structure (comparative example shown in FIG. 14) in which the arc running surface 33 of 13 is set to the extension line L1 of the contact fixing surface, the arc is further extended, the arc voltage is further increased, and the current limiting performance is improved. improves. As a result, the amount of pyrolysis gas generated from the cooling member 23 is reduced, and an excessive pressure increase in the arc extinguishing apparatus 10 can be avoided.

  The arc running surface 33 of the contact support piece 13 may have a stepped shape, an inclined surface, or a combination of these, but in this embodiment, the arc running surface 33 of the contact support piece 13 is fixed as the arc running surface 33 goes to the tip side. The arc A smoothly travels compared to such a staircase structure because the arc travel surface 33 has a structure that is gradually and gradually separated from the surface extension line L1, that is, the arc travel surface 33 is not a staircase structure. As a result, the arc current decreasing speed (arc current limiting speed) is increased.

  Further, according to the arc extinguishing device 10 of the present embodiment, the distal end side of the contact support piece 13 with respect to the fixed contact 16 is gradually formed thinner toward the distal end, so that the arc running surface 33 of the contact support piece 13 is formed. The shape gradually becomes farther away from the extension line L1 of the contact fixing surface as it goes to the tip side.

  Therefore, the step between the arc travel surface 33 of the contact support piece 13 and the arc travel surface 25 of the travel plate 24 is reduced, so that the arc travels from the arc travel surface 33 of the contact support piece 13 to the arc travel surface 25 of the travel plate 24. A becomes easy to change, and the time during which the arc A stays at the tip of the contact support piece is shortened. Therefore, the arc current limiting speed is further increased.

  Hereinafter, other embodiments of the present invention will be described. In addition, about the structure similar to the above-mentioned embodiment, the same code | symbol is attached | subjected and description of the structure and effect is abbreviate | omitted.

Second Embodiment Next, an arc extinguishing device 10 according to a second embodiment of the present invention will be described with reference to FIG.

  The arc extinguishing device 10 of the second embodiment is different from the arc extinguishing device of the first embodiment in the shape of the contact support piece 13 and the shape of the travel plate 24, and the other points are the same as in the first embodiment.

  The contact support piece 13 has the same thickness from the base end 13b to the tip end 13a as in the comparative example (FIG. 14), and the arc running surface 33 of the contact support piece 13 is fixed to the contact as in the comparative example (FIG. 14). It is set on the extension line L1 of the surface 31 and does not include a stepped portion or an inclined surface.

  On the other hand, the travel plate 24 is formed in a crank shape at a position close to the tip 13 a of the contact support piece 13, and thereby, between the arc travel surface 33 of the contact support piece 13 and the arc travel surface 25 of the travel plate 24. A rising step is formed on the surface. That is, the arc travel surface 25 of the travel plate 24 is located above the tip of the arc travel surface 33 of the contact support piece 13 (movable contact 19 side). In other words, the tip of the arc travel surface 33 of the contact support piece 13 is located below the arc travel surface 25 of the travel plate 24 (on the side opposite to the movable contact 19).

  The surface of the traveling plate 24 includes an attachment surface 27 attached to the lower surface of the contact support piece 13, an arc traveling surface 25 provided substantially parallel to the attachment surface 27 at a position higher than the attachment surface 27, and the attachment surfaces 27. And an arc running surface 25 and a crossing surface 26 that is smoothly continuous and intersects with both. The intersecting surface 26 of the travel plate 24 extends from the lower surface side of the contact support piece 13 toward the upper surface side, and intersects the extension line L2 of the arc travel surface 33 on the upper surface of the contact support piece 13 at a substantially right angle. Thus, the arc travel surface 25 of the travel plate 24 is located closer to the movable contact 19 than the extension line L2 of the arc travel surface 33 of the contact support piece 13.

  When the travel plate 24 is formed in a crank shape, the traveling plate 24 is fixed to the lower surface of the contact support piece 13 and extends substantially parallel to the contact support piece 13, and is substantially from the base end portion 24 b. An intersecting portion 27 that is bent at a right angle and substantially orthogonal to the base end portion 24b; and a distal end portion 28 that is bent from the intersecting portion 27 at a substantially right angle toward the distal end direction and extends substantially parallel to the base end portion 24b. , And is configured.

  According to the arc-extinguishing device 10 of the second embodiment, the traveling plate 24 is formed in a crank shape at a position close to the tip 13a of the contact support piece 13 so that it travels from the arc travel surface 33 of the contact support piece 13. There is a step up to the arc running surface 25 of the plate 24. For this reason, when the arc travels on the arc travel surface 33 of the contact support piece 13 in the tip direction, it comes into contact with the intersecting surface 27b of the travel plate 24 due to the arcuate bulge of the arc, and the structure of the descending step (for example, FIG. The arc is transferred from the contact support piece 13 to the traveling plate 24 at an earlier timing than the comparative example 14). Further, since it is an ascending step, the potential difference when the arc changes from the arc traveling surface 33 of the contact support piece 13 to the arc traveling surface 25 of the traveling plate 24 compared to the structure of the descending step (for example, the comparative example of FIG. 14). Thus, the arc is quickly transferred from the contact support piece 13 to the traveling plate 24. As a result, the dwell time when the arc commutates from the contact support piece 13 to the traveling plate 24 is shortened, so that the arc current decreases smoothly without stagnation, thereby improving the current limiting performance.

Third Embodiment FIGS. 7 and 8 show an arc extinguishing device 10 according to a third embodiment of the present invention. In the arc extinguishing device 10 of the third embodiment, the contact support piece 13 has the same structure as that of the first embodiment, and the traveling plate 24 has the same structure as that of the second embodiment. Therefore, the effect which combined 1st Embodiment and 2nd Embodiment is acquired.

Fourth Embodiment Next, an arc extinguishing device according to a fourth embodiment of the present invention will be described with reference to FIGS. The arc extinguishing device 10 according to the fourth embodiment is different from the first to third embodiments in the shape of the contact support piece 13 and the shape of the travel plate 24. In the fourth embodiment, the travel plate 24 is formed by bending the distal end side 24a thereof, so that the base end side flat portion 41 extends as it is from the base end portion 24b, and the base end side flat portion 41 extends upward. An inclined portion 43 that is bent to the (movable contact side) and extends while being inclined with respect to the flat portion 41, and a distal end side that is bent from the inclined portion 43 and extends substantially parallel to the proximal end flat portion 41. And a flat portion 45. An opening window 47 is formed from the base end side flat portion 41 to the inclined portion 43.

  On the other hand, the contact support piece 13 is bent toward the opposite side of the movable contact 19 from the distal end side of the contact support piece 13 with respect to the fixed contact 16. Thereby, the arc running surface 33 of the contact support piece 13 is configured to include an inclined surface 49 that moves away from the extension line L1 of the contact fixing surface as it goes to the tip side of the contact support piece 13.

  Further, the front end 13 a of the contact support piece 13 extends from the opening window 47 of the travel plate 24 to the back side of the travel plate 24 and is located on the side farther from the movable contact 19 than the travel plate 24.

  Hereinafter, effects of the arc extinguishing device 10 according to the fourth embodiment will be listed.

  According to the arc extinguishing device 10 of the fourth embodiment, the structure gradually moves away from the extension line L1 of the contact fixing surface 31 as the arc running surface 33 of the contact support piece 13 goes to the tip side as in the first embodiment. It is. Therefore, compared with the structure (the comparative example of FIG. 14) in which the arc running surface 33 of the contact support piece 13 is set to the extension line L1 of the contact fixing surface 31, the arc is further extended and the arc voltage is further increased. Become. Therefore, the current limiting performance is improved, and as a result, the amount of pyrolysis gas generated from the cooling member is reduced, and an excessive pressure increase in the arc extinguishing apparatus can be avoided.

  According to the arc extinguishing device 10 of the fourth embodiment, the arc running surface 33 of the contact support piece 13 is not stepped like the first embodiment, that is, the arc running surface 33 of the contact support piece 13 is on the tip side. It is a structure that gradually and gradually moves away from the extension line L1 of the contact fixing surface 31 as it goes. Therefore, compared with the structure (the comparative example of FIG. 14) in which the arc running surface 33 of the contact support piece 13 is formed in a staircase shape, the arc A can run smoothly, so that the current limiting performance is further improved.

  According to the arc extinguishing apparatus 10 of the fourth embodiment, the above structure can be obtained by bending the tip side of the contact support piece 13 from the fixed contact 16 toward the side opposite to the movable contact 19. And manufacturing cost can be reduced.

  According to the arc extinguishing device 10 of the fourth embodiment, the traveling plate 24 includes the opening window 47, and the tip 13 a of the contact support piece 13 is pulled from the opening window 47 of the traveling plate 24 to move away from the movable contact 19 than the traveling plate 24. Located on the far side. Therefore, unlike the structure (a comparative example in FIG. 14) where the arc travel surface 33 of the contact support piece 13 descends from the arc travel surface 33 to the arc travel surface 25 of the travel plate 24, the arc travel surface 33 of the contact support piece 13 Since there is a step up to the arc travel surface 25 of the travel plate 24, the arc A can easily transfer from the arc travel surface 33 of the contact support piece 13 to the arc travel surface 25 of the travel plate 24. Thereby, since the residence time of the arc A when the arc commutates from the contact support piece 13 to the traveling plate 24 is shortened, the current limiting performance is further improved.

Fifth Embodiment Next, a fifth embodiment of the present invention will be described with reference to FIGS. In the fifth embodiment, the shape of the contact support piece 13 is the same as that of the second embodiment, but the shape of the traveling plate 24 is different from those of the first to fourth embodiments.

  The traveling plate 24 is bent and formed as a flat portion 51 on the base end side that is extended as it is from the base end portion 24b, and the flat portion 51 is bent obliquely downward (in a direction away from the movable contact) from the base end side flat portion 51. A downwardly inclined part 53 extending obliquely with respect to the part 51, and a tip part 55 wound back from the downwardly inclined part 53 toward the movable contact 19 in a substantially C shape (substantially U shape). Has been.

  With such a structure, a portion of the arc traveling surface 25 of the traveling plate 24 where the upper surface of the descending inclined portion 53 moves away from the extension line L1 of the contact fixing surface 31 as the distance from the fixed contact 16 increases (in this example, It is configured as a smooth inclined surface 53a).

  The C-shaped distal end portion 55 of the traveling plate 24 is bent from the downward inclined portion 53 and extends substantially parallel to the proximal end side flat portion 51, and the upper side from the lower flat portion 57. A vertical portion 59 that is bent substantially perpendicularly to the lower flat portion 57, and an upper flat portion 61 that is bent at a substantially right angle from the vertical portion 59 toward the movable contact 19 and faces the lower flat portion 57, Are formed in a substantially C-shape.

  Of the distal end portion 55 of the traveling plate 24, the end portion on the movable contact 19 side, that is, the upper flat portion 61 is formed wider than the base end side (vertical portion 59 in this example). In other words, a constricted portion (in this example, a vertically oriented portion 59) having a width narrower than that of the terminal portion 61 is provided on the base end side of the terminal portion (upper flat portion 61). The terminal portion 61 is provided with a slit-shaped notch 61a extending in the traveling direction of the arc A.

  Next, effects of the fifth embodiment will be listed.

  According to the fifth embodiment configured as described above, the arc traveling surface 25 of the traveling plate 24 has the inclined surface 53a that is separated from the extension line L1 of the contact fixing surface 31 as the distance from the fixed contact 16 increases. Therefore, compared with the structure (the comparative example of FIG. 14) in which the arc running surface 25 is parallel to the extension line L1 of the contact fixing surface 31, the arc is further extended and the arc voltage is further increased. Therefore, the current limiting performance is improved, and as a result, the amount of pyrolysis gas generated from the cooling member 23 is reduced, and an excessive pressure increase in the arc extinguishing apparatus 10 can be avoided.

  Since the arc travel surface 25 of the travel plate 24 is not formed in a step shape, the arc travels smoothly without stagnation compared to the case where the arc travel surface 25 has a step shape, so that the rate of decrease in the arc current is increased. There is also an advantage of speed.

  In addition, according to the fifth embodiment, the traveling plate 24 has its tip portion 55 wound back in a substantially C shape on the movable contact 19 side, so that the arc A travels on the distal end portion 55 side of the traveling plate 24. When it comes, the terminal portion (the upper flat portion 61 in this example) on the movable contact side of the tip portion 55 of the traveling plate 24 comes close to the traveling arc A. At this time, since the terminal portion 61 acts as a heat absorbing portion that receives the heat of the arc A, the arc current is reduced more quickly by cooling the arc A. That is, the current limiting performance is further improved. Thereby, the amount of pyrolysis gas generated from the cooling member 23 can be further reduced.

  In addition, compared with the structure where the front-end | tip part of the traveling plate 24 was formed in L shape like the traveling plate 24 of 1st Embodiment, the traveling plate 24 of 5th Embodiment is rolled back in C shape and mentioned above. As described above, since the terminal portion (upper flat portion 61) extending to the movable contact side is provided, the terminal portion 61 comes closer to the arc at an earlier timing, and the traveling plate 24 as a whole has more portions that are close to the arc.

  Further, according to the fifth embodiment, since the terminal portion 61 on the movable contact side is wider than the base end side (vertical portion 59 in this example), the heat capacity increases and the cooling amount of the arc A increases. . Thereby, the current limiting performance is further improved.

  In other words, since the constricted portion (in this example, the vertical portion 59) having a width smaller than that of the terminal portion 61 is provided on the base end side of the terminal portion 61 on the movable contact side, the terminal portion 61 receives heat. When the heat of the arc A is large due to the constriction effect and the energy of the arc A is large, the terminal portion 61 becomes high temperature and easily evaporates, and the arc A is rapidly cooled by this latent heat of vaporization. There is expected.

  Moreover, according to 5th Embodiment, the slit-shaped notch part 61a extended in the traveling direction of the arc A is provided in the terminal part 61 by the side of a movable contact. Therefore, the traveling arc A can be finally passed through the slit-shaped notch 61a. When the arc A penetrates the slit-shaped notch 61a, the arc A can be traveled to a position farther from the movable contact 19, and the terminal 61 is close to the arc A so as to surround the arc A. Therefore, the heat receiving area of the terminal unit 61 is widened. Therefore, both the arc voltage increase effect and the arc cooling effect due to arc extension are improved, and the current limiting performance is further improved.

  It should be noted that the present invention is not limited only to the above-described embodiment, and it goes without saying that various aspects are possible for details.

The side view which shows the circuit breaker incorporating the arc-extinguishing apparatus of 1st Embodiment of this invention. The exploded perspective view of the arc-extinguishing device. It is sectional drawing of the arc-extinguishing apparatus, Comprising: The figure which shows the state at the time of closing. Sectional drawing immediately after opening of the arc-extinguishing device. Sectional drawing which shows the state which the pole extinguishing apparatus opened greatly. It is sectional drawing of the arc-extinguishing apparatus of 2nd Embodiment of this invention, Comprising: The figure which shows the state opened greatly. The disassembled perspective view of the stationary contact and traveling board of the arc-extinguishing apparatus of 3rd Embodiment of this invention. It is sectional drawing of the arc-extinguishing apparatus of 3rd Embodiment of this invention, Comprising: The figure which shows the state opened greatly. The disassembled perspective view of the stationary contact and travel board of the arc-extinguishing apparatus of 4th Embodiment of this invention. It is sectional drawing of the arc-extinguishing apparatus of 4th Embodiment of this invention, Comprising: The figure which shows the state opened greatly. The disassembled perspective view of the stationary contact and traveling board of the arc-extinguishing apparatus of 5th Embodiment of this invention. It is sectional drawing of the arc-extinguishing apparatus of 5th Embodiment of this invention, Comprising: The figure which shows the state opened greatly. The top view of the traveling board of the arc-extinguishing apparatus of 5th Embodiment of this invention. It is sectional drawing of the arc-extinguishing apparatus of a comparative example, Comprising: The figure which shows the state opened greatly.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Circuit breaker 10 ... Arc-extinguishing device 11 ... Fixed contact 12 ... Terminal part 12a ... Tip 12b ... Base end 13 ... Contact support piece 13a ... Tip 13b ... Base end 14 ... Drive coil part 16 ... Fixed contact 18 ... Movable Contact 19 ... Moving contact 24 ... Running plate 25 ... Arc running surface of running plate 27 ... Crank portion 27b ... Intersection surface 31 ... Contact fixing surface of contact support piece 33 ... Arc running surface of contact support piece 47 ... Opening window 55 ... Front end 59 ... Longitudinal part (base end side of terminal part)
61 ... Upper flat part (terminal part on the movable contact side of the tip part)
61a ... slit-shaped notch L1 ... extension line of contact fixing surface of contact support piece L2 ... extension line of arc running surface of contact support piece A ... arc Z ... running direction of arc

Claims (10)

A terminal portion provided at one end portion, a contact support piece extending from the other end portion to the vicinity of the terminal portion and having a fixed contact fixed in the vicinity of its longitudinal end, and the one end portion on both sides of the contact support piece; A stationary contact having a drive coil connected to the other end and generating magnetic flux by energization;
A movable contact that has a movable contact that comes into contact with the fixed contact, and that allows the fixed contact and the movable contact to be separated from each other;
With
An arc extinguishing device that causes an arc generated when the movable contact is opened from the fixed contact to travel from the fixed contact toward the tip of the contact support piece by a magnetic field generated by the drive coil unit,
The arc extinguishing device according to claim 1, wherein the arc running surface of the contact support piece is gradually separated from the extension line of the contact fixing surface of the contact support piece as it goes to the tip side. The arc extinguishing device according to claim 1,
The arc extinguishing device, wherein the tip end side of the contact support piece is gradually thinned toward the tip end. The arc extinguishing device according to claim 1,
An arc extinguishing device, wherein a tip end side of the contact support piece is bent toward a side opposite to the movable contact. A terminal portion provided at one end portion, a contact support piece extending from the other end portion to the vicinity of the terminal portion and having a fixed contact fixed in the vicinity of its longitudinal end, and the one end portion on both sides of the contact support piece; A stationary contact having a drive coil connected to the other end and generating magnetic flux by energization;
A movable contact that has a movable contact that comes into contact with the fixed contact, and that allows the fixed contact and the movable contact to be separated from each other;
A conductive running plate that is disposed in contact with the back surface of the surface on which the fixed contact of the contact support piece is fixed and protrudes from the tip of the contact support piece;
With
An arc extinguishing device that causes an arc generated when the movable contact is opened from the fixed contact to travel from the fixed contact toward the tip of the contact support piece by a magnetic field generated by the drive coil unit,
The traveling plate is formed in a crank shape at a position close to the tip of the contact support piece, thereby forming an ascending step from the arc travel surface of the contact support piece to the arc travel surface of the travel plate. Arc extinguishing device characterized. A terminal portion provided at one end portion, a contact support piece extending from the other end portion to the vicinity of the terminal portion and having a fixed contact fixed in the vicinity of its longitudinal end, and the one end portion on both sides of the contact support piece; A stationary contact having a drive coil connected to the other end and generating magnetic flux by energization;
A movable contact that has a movable contact that comes into contact with the fixed contact, and that allows the fixed contact and the movable contact to be separated from each other;
A conductive running plate that is disposed in contact with the back surface of the surface on which the fixed contact of the contact support piece is fixed and protrudes from the tip of the contact support piece;
With
An arc extinguishing device that causes an arc generated when the movable contact is opened from the fixed contact to travel from the fixed contact toward the tip of the contact support piece by a magnetic field generated by the drive coil unit,
The travel plate includes an opening window,
An arc extinguishing device, wherein a tip of the contact support piece is located on a side farther from the movable contact than the traveling plate by being pierced from an opening window of the traveling plate. A terminal portion provided at one end portion, a contact support piece extending from the other end portion to the vicinity of the terminal portion and having a fixed contact fixed in the vicinity of its longitudinal end, and the one end portion on both sides of the contact support piece; A stationary contact having a drive coil connected to the other end and generating magnetic flux by energization;
A movable contact that has a movable contact that comes into contact with the fixed contact, and that allows the fixed contact and the movable contact to be separated from each other;
A conductive running plate that is disposed in contact with the back surface of the surface on which the fixed contact of the contact support piece is fixed and protrudes from the tip of the contact support piece;
With
An arc extinguishing device that causes an arc generated when the movable contact is opened from the fixed contact to travel from the fixed contact toward the tip of the contact support piece by a magnetic field generated by the drive coil unit,
An arc extinguishing device, wherein an arc running surface of the running plate has an inclined surface that is separated from an extension line of the contact fixing surface as the distance from the fixed contact increases. A terminal portion provided at one end portion, a contact support piece extending from the other end portion to the vicinity of the terminal portion and having a fixed contact fixed in the vicinity of its longitudinal end, and the one end portion on both sides of the contact support piece; A stationary contact having a drive coil connected to the other end and generating magnetic flux by energization;
A movable contact that has a movable contact that comes into contact with the fixed contact, and that allows the fixed contact and the movable contact to be separated from each other;
A conductive running plate that is disposed in contact with the back surface of the surface on which the fixed contact of the contact support piece is fixed and protrudes from the tip of the contact support piece;
With
An arc extinguishing device that causes an arc generated when the movable contact is opened from the fixed contact to travel from the fixed contact toward the tip of the contact support piece by a magnetic field generated by the drive coil unit,
The arc extinguishing apparatus according to claim 1, wherein a tip end portion of the traveling plate is wound back in a substantially C shape toward the movable contact. An arc extinguishing device according to claim 7,
The arc extinguishing device according to claim 1, wherein a terminal portion on the movable contact side of a distal end portion of the traveling plate is wider than a proximal end side thereof. An arc extinguishing device according to claim 7,
An arc extinguishing device, characterized in that a constricted portion having a width narrower than that of the terminal portion is provided on the base end side of the distal end portion of the travel plate on the movable contact side. The arc extinguishing device according to any one of claims 7 to 9,
An arc extinguishing device, wherein a slit-shaped cutout portion extending in a traveling direction of the arc is provided at a terminal portion on a movable contact side of a distal end portion of the traveling plate.

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