JP2016033891A - DC breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a DC breaker that makes it possible to easily provide an arc-extinguishing device or a contact part.SOLUTION: There is provided a holding member 36 integrally comprising a magnet holding part 29 for holding a permanent magnet 25 and a contact holding part 28 into which a fixed contact part 17 can be inserted. A yoke 38 covers the holding member 36 including magnet holding parts 29, 29 holding permanent magnets 25, 25 and the contact holding part 28 holding the fixed contact part 17. A positioning projection is provided on the holding member 36, enabling positioning of an arc-extinguishing device by inserting the positioning projection into a positioning recess 39 formed on the breaker case 2 side. Thereby, work for installing the arc-extinguishing device is made to be very easy.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a DC circuit breaker that interrupts an electric circuit when an electric circuit abnormality such as an overcurrent occurs, and more particularly to a DC circuit breaker in which an arc extinguishing device is provided in an arc extinguishing chamber in which a contact portion that performs an interruption operation is arranged.

  Conventionally, in a DC circuit breaker, when an abnormal current such as an overcurrent flows in an electric circuit, the electric circuit is interrupted. At the time of this interruption, arc discharge occurs between the contacts. Since this arc discharge has an adverse effect on the surroundings, it is configured so that the arc discharge can be extinguished in a short time by surrounding the contact portion that performs the interruption operation with an arc extinguishing chamber and providing an arc extinguishing device in the arc extinguishing chamber. .

  And as said arc-extinguishing apparatus, what attached the several arc grid to the arc-extinguishing board and arrange | positioned the magnet in the vicinity of the contact part are employ | adopted widely. For example, in the invention described in Patent Document 1, both of the configurations are adopted, and a plurality of grids arranged so as to overlap in the vertical direction in front of the contact portion and a fixed contact between the left and right sides of the U An arc extinguishing device having a magnet bent in a letter shape is installed. And the arc which generate | occur | produces is pulled to the grid side, and rapid arc extinction is enabled by making it contact with a grid.

JP 2005-216807 A

  However, in the invention described in Patent Document 1, the arc-extinguishing plate, the fixing bracket having the stationary contact, the magnet, and the like must be separately installed, so that the installation work of the arc-extinguishing device and the contact portion is troublesome. There is.

  Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a DC circuit breaker in which an arc extinguishing device and a contact portion can be easily installed.

  In order to achieve the above object, according to the present invention, a power supply side terminal is provided on the front side of the circuit breaker case, and a load side terminal is provided on the rear side, respectively, and between the power supply side terminal and the load side terminal. When a contact part composed of a fixed contact and a movable contact is provided on the arranged electric circuit, and an arc extinguishing device is installed in an arc extinguishing chamber in which the contact part is arranged, and an abnormal current flows in the electric circuit A DC circuit breaker that opens the contact portion to cut off the electric circuit, wherein the fixed contact is provided on the surface of the metal plate-like fixed contact portion, while the arc-extinguishing device A pair of arc extinguishing plates attached so as to be sandwiched between them, a plurality of grids stacked between the arc extinguishing plates, and a set of permanent magnets attached to the left and right sides of the fixed contact, A magnet holding portion for holding a magnet, and the fixed contact portion; A holding member integrally provided with a pluggable contact holding portion is provided, and the permanent magnet is covered with the magnet holding portion, and the holding member holding the fixed contact portion with the contact holding portion is covered with a yoke. In addition, a positioning engagement portion is provided on the yoke, and a positioned engagement portion capable of engaging the positioning engagement portion on the circuit breaker case side is provided.

  According to the present invention, a holding member that integrally includes a magnet holding portion that holds a permanent magnet and a contact holding portion into which a fixed contact portion can be inserted is provided, and the permanent magnet is used as the contact holding portion. The holding members holding the fixed contact portions are each covered with a yoke, and a positioning engagement portion is provided on the yoke, and a positioning engagement portion on which the positioning engagement portion can be engaged is provided on the circuit breaker case side. . Therefore, since the permanent magnet, the yoke, and the fixed contact can be positioned simply by engaging the positioning engagement portion with the positioned engagement portion, the arc extinguishing device and the contact portion are installed more easily than in the past. be able to.

It is explanatory drawing which showed the DC circuit breaker from the upper surface side. It is explanatory drawing which showed the AA line cross section in FIG. It is the isometric view explanatory drawing which showed the arc-extinguishing apparatus and the 1st fixing bracket in a decomposition | disassembly state from the rear side. It is the isometric view explanatory view which showed the arc-extinguishing apparatus and the 1st fixing bracket in a decomposition | disassembly state from the front side. It is sectional explanatory drawing which showed the positional relationship of the arc-extinguishing apparatus in the assembly | attachment state, a 1st fixed contact, and a 1st movable contact. It is explanatory drawing which showed the positional relationship of the arc-extinguishing apparatus, the 1st fixed contact, and the 1st movable contact in an assembly state from the upper part. It is explanatory drawing which showed a mode that an arc was pulled by the permanent magnet. It is explanatory drawing which showed the installation structure of the arc-extinguishing apparatus to a DC circuit breaker. It is explanatory drawing which showed the further example of a change of a holding member.

  Hereinafter, the DC circuit breaker according to the present invention will be described in detail with reference to the drawings.

(First embodiment)
First, the DC circuit breaker 1 according to the first embodiment will be described.
FIG. 1 is an explanatory view showing the DC circuit breaker 1 from the upper surface side. FIG. 2 is an explanatory view showing a cross section taken along line AA in FIG.

  The DC circuit breaker 1 is provided with a power supply side terminal 3 at the front part of a circuit breaker case 2 made of synthetic resin and a load side terminal 4 at the rear part. In order to electrically connect 3 and the load side terminal 4, two electric circuits extending in the front-rear direction are arranged side by side. And each electric circuit has the 1st fixed contact 5 in the rear end, has the 1st fixed metal fitting 6 which extends to the power source side terminal 3 side, and constitutes the front electric circuit, and the 2nd fixed contact 7 in the front end, A second fixed fitting 8 that extends to the load side terminal 4 and constitutes a rear circuit, a first movable contact 9 at the front end, and a second movable contact 10 at the rear end, each having a horizontal direction as an axis. A movable contact member 11 is provided that electrically connects / disconnects the front circuit and the rear circuit by bringing the movable contacts 9, 10 into contact / separation with respect to the fixed contacts 5, 7 by a rotating operation. . Further, for each electric circuit, a conventionally known breaking mechanism (not shown) for rotating the movable contact member 11 in a direction in which the movable contacts 9 and 10 are separated from the fixed contacts 5 and 7, an electric circuit When an overcurrent such as a short-circuit current flows through the electromagnetic trip device 12 that operates to operate the shut-off mechanism, and an operation member (not shown) that directly operates the shut-off mechanism by receiving the operation of the electromagnetic trip device 12 Etc. are also provided. Further, arc extinguishing chambers 22 and 22 are formed in each electric circuit so as to surround a contact portion composed of the fixed contacts 5 and 7 and the movable contacts 9 and 10, and the arc extinguishing chambers 22 are interrupted. An arc extinguishing device 21 is installed for quickly extinguishing an arc generated when the movable contacts 9 and 10 are separated from the fixed contacts 5 and 7 by the operation. Reference numeral 13 denotes an operation lever for turning on / off the electric circuit.

Here, the arc-extinguishing device 21 which is a main part of the present invention will be described in detail with reference to FIGS.
FIG. 3 is a perspective explanatory view showing the arc extinguishing device 21 and the first fixing bracket 6 in a disassembled state from the rear side. FIG. 4 is a perspective explanatory view showing the arc extinguishing device 21 and the first fixing bracket 6 in a disassembled state from the front side. FIG. 5 is an explanatory cross-sectional view showing the positional relationship among the arc extinguishing device 21, the first fixed contact 5, and the first movable contact 9 in the assembled state. FIG. 6 is an explanatory view showing the positional relationship between the arc extinguishing device 21, the first fixed contact 5, and the first movable contact 9 in the assembled state from above. FIG. 7 is an explanatory view showing a state in which the arc is pulled by the permanent magnet 25. 5 and 6, the holding member 26 is omitted.

  The arc extinguishing device 21 includes a pair of arc extinguishing plates 23 and 23 attached so as to sandwich the contact portion from the left and right sides, and a plurality of grids 24, 24. And a set of permanent magnets 25, 25 attached to the left and right sides of the first fixed contact 5 in a predetermined direction, and a holding member 26 for holding the permanent magnets 25, 25. The arc extinguishing plate 23 is a plate-like body formed of a synthetic resin excellent in insulation and arc resistance (for example, 6 nylon added with about 30% glass fiber as a filler). It is arrange | positioned so that the left wall surface or right wall surface of may be covered. Further, a notch 27 having a predetermined width in the front-rear direction in which the magnet holding portion 29 of the holding member 26 can be fitted is provided on the lower side of the arc extinguishing plate 23.

  Each grid 24 is a metal plate formed in a substantially U shape in a top view having a pair of leg portions extending in parallel and a connecting portion connecting one end of the leg portions. The grids 24, 24,... Are in a state where a plurality of arc extinguishing plates 23, 23 are stacked in the vertical direction at predetermined intervals so that the connecting portion faces forward. In addition, each grid 24 inserts engagement pieces 24a and 24a projecting outward from the left and right side portions of the grid 24 into engagement holes formed in the respective arc extinguishing plates 23, thereby providing the grids 23 and 23. It is built between.

  Like the arc extinguishing plate 23, the holding member 26 is formed of a synthetic resin excellent in insulation and arc resistance, and has a contact holding portion 28 that holds the fixed contact portion 17 of the first fixing bracket 6, A pair of magnet holding portions 29 and 29 are provided to stand upward from the contact holding portion 28. The contact holding portion 28 is provided with a concave portion 28a that opens upward and forward on the upper surface of a rectangular block body, and the concave portion 28a has a thickness in the vertical direction of the fixed contact portion 17 of the first fixture 6. The fixed contact portion 17 can be inserted into the recess 28a. Further, the upper surface portion 28b of the contact holding portion 28 on the rear side of the concave portion 28a functions as a stopper with which the rear end surface of the fixed contact portion 17 abuts when the fixed contact portion 17 is inserted, and the arc-extinguishing with the holding member 26. It also functions as a stopper with which the lower side of the arc-extinguishing plate 23 comes into contact when the plate 23 is assembled. On the other hand, each magnet holding part 29 is formed in a box shape opened to the left and right outer sides, respectively, and can hold the permanent magnet 25 housed inside from the opening. The length of the magnet holding portion 29 in the front-rear direction is the same as the length of the notch 27 provided in the lower side portion of the arc extinguishing plate 23. Further, the inner side of the magnet holding portion 29 in the left-right direction protrudes above the recess 28a, and its lower surface comes into contact with the upper surface of the fixed contact portion 17 inserted into the recess 28a. It also acts as a mechanism for holding the portion 17.

  The first fixing bracket 6 will also be described. The first fixing bracket 6 has a plate-like fixed contact portion 17 extending substantially horizontally rearward, and an upper surface of the tip (rear end) of the fixed contact portion 17. The 1st fixed contact 5 is provided in this. In addition, an arc running portion 18 for promoting the extension of the generated arc is cut and raised on the front side of the first fixed contact 5 in the fixed contact portion 17.

The arc extinguishing device 21 and the first fixing bracket 6 made of the above components are assembled as follows.
First, the grids 24, 24,... Are installed between the arc extinguishing plates 23, 23, and the grids 24, 24,. On the other hand, the fixed contact portion 17 of the first fixed fitting 6 is inserted into the recess 28a of the contact holding portion 28 with the first fixed contact 5 facing upward, and the first fixed fitting 6 and the holding member 26 are integrated. . Further, the permanent magnets 25 are held in the respective magnet holding portions 29 so that the permanent magnets 25 and 25 and the holding member 26 are integrated. At this time, in consideration of the direction of current flow, one permanent magnet 25 is held by the magnet holders 29 and 29 in such a posture that the north pole faces the other and the south pole faces the inside in the left-right direction. . For example, as shown in FIG. 7A, if a current flows from the back of the paper to the front (from the first fixed contact 5 to the first movable contact 9), the direction of the magnetic field changes from left to right. Permanent magnets 25 and 25 are arranged so as to be. Then, a force is applied to the front side with respect to the arc generated between the two contacts, and the arc extends to the front side, that is, the arc running portion 18 and the grids 24, 24,... As shown in FIG. It will be. Finally, in the notches 27 and 27 of the arc extinguishing plates 23 and 23 integrated with the grids 24, 24..., The magnet of the holding member 26 integrated with the first fixing bracket 6 and the permanent magnets 25 and 25. By fitting the holding portions 29 and 29 and integrating them, the arc extinguishing plates 23 and 23, the grids 24 and 24, the permanent magnets 25 and 25, and the fixed contact portion 17 are positioned at positions as described later. In the state, the arc-extinguishing device 21 and the first fixture 6 are assembled.

  In the assembled arc-extinguishing device 21 and the first fixed bracket 6, the permanent magnets 25, 25 are arranged between the rear end of the first fixed contact 5 and the middle of the arc traveling portion 18 (that is, the front end of the arc traveling portion 18. It is located so as to overlap in a side view over a position that does not exceed. As shown in FIG. 5, the legs of all the grids 24, 24,... Protrude to the rear side of the front ends of the permanent magnets 25, 25, and the front ends of the connecting parts of all the grids 24, 24,. Is located in front of the front ends of the permanent magnets 25, 25. That is, the first fixed contact 5, the permanent magnets 25, 25, and the grids 24, 24... Are positioned at suitable positions. Therefore, after that, the arc extinguishing device 21 and the first fixing bracket 6 are installed so that the arc extinguishing device 21 is located in the arc extinguishing chamber 22, and the first movable contact 9 is the legs of the grids 24, 24. If the movable contact member 11 is installed so as to be in contact with / separated from the first fixed contact 5 while moving between them, the installation of the contact portion and the arc extinguishing device 21 in the DC circuit breaker 1 is completed. As the arc extinguishing device on the second fixed contact 7 and the second movable contact 10 side, a device in which the arc extinguishing device 21 is turned upside down and back and forth may be used.

  According to the DC circuit breaker 1 having the above-described configuration, the contact holding portion 28 that can be integrated by inserting the fixed contact portion 17 of the first fixing bracket 6 into the holding member 26 that holds the permanent magnets 25, 25. And notches 27, 27 that can be integrated by fitting the magnet holding portions 29, 29 of the holding member 26 into the arc extinguishing plates 23, 23. The permanent magnets 25 and 25 are held by the magnet holding portions 29 and 29, and the fixed contact portion 17 is held by the contact holding portion 28, and the arc extinguishing plate 23 and the holding member 26 to which the grids 24, 24,. , The arc extinguishing plates 23, 23, grids 24, 24..., Permanent magnets 25, 25, arc running part 18, and first fixed contact 5 (and thus contact part) are positioned. It has become so. Therefore, the components necessary for quick arc extinguishing can be easily and surely arranged in a suitable positional relationship, the arc extinguishing action can be improved, and the arc extinguishing device 21 is assembled as one unit. As a result, the installation work of the arc extinguishing device 21 is facilitated.

Further, since the magnet holding portions 29 and 29 are used for engagement with the arc extinguishing plate 23, the configuration of the holding member 26 can be rationalized, the structure of the holding member 26 can be simplified, and the like. There is an effect.
Further, the permanent magnets 25, 25 are positioned so as to overlap in a side view from the rear end of the first fixed contact 5 to the middle of the arc running portion 18, while the legs of all the grids 24, 24. It protrudes to the rear side from the front ends of the permanent magnets 25, 25, and the front ends of the connecting portions of all the grids 24, 24... Are located in front of the front ends of the permanent magnets 25, 25. Therefore, it can be set as the DC circuit breaker 1 excellent in arc extinguishing action.

(Second embodiment)
Next, a DC circuit breaker according to the second embodiment will be described.
FIG. 8 is an explanatory view showing an installation structure of the arc extinguishing device (holding member 36 and yoke 38) to the DC circuit breaker. In FIG. 8, the same components as those of the first embodiment are denoted by the same reference numerals.

  The direct current circuit breaker of the second embodiment is different from the direct current circuit breaker 1 of the first embodiment in the configuration relating to the installation of the arc extinguishing device and the arc extinguishing device. The holding member 36 constituting the arc extinguishing device installed in the DC circuit breaker, like the holding member 26, has a contact holding portion 28 that holds the fixed contact portion 17, and a pair of magnet holding portions 29 that holds the permanent magnet 25, 29. On the other hand, on the bottom surface of the contact holding portion 28 of the holding member 36, a positioning projection 37 for positioning the installation position of the holding member 36 (and thus the arc extinguishing device) is provided so as to protrude downward. In addition, a yoke 38 is attached to the holding member 36 for improving the magnetic flux collecting action of the permanent magnets 25 and 25. The yoke 38 is formed to be bent along the left and right side surfaces and the bottom surface of the holding member 36 in a state where the permanent magnets 25, 25 are held by the magnet holding portions 29, 29. Therefore, by attaching the yoke 38, the opening of the magnet holding portion 29 is covered, and a positioning projection is formed in which the surface of the positioning projection 37 is covered with the yoke 38.

  And the arc-extinguishing apparatus which has the said holding member 36 attached the arc-extinguishing board, the grid, the 1st fixing bracket 6, the permanent magnets 25 and 25, and the yoke 38 like the arc-extinguishing apparatus 21 of 1st Example. After integrating the holding member 36 in the state, the positioning convex portion is fitted into the positioning concave portion 39 formed on the circuit breaker case 2 side to position the installation position of the arc extinguishing device. Then, if the fixing screw 41 is screwed into the yoke 38 through the screw hole 40 formed in the positioning recess 39 and the arc extinguishing device is screwed, the contact portion of the DC circuit breaker 1 and the arc extinguishing device Installation is complete. In FIG. 8, the screw holes on the yoke 38 side are omitted.

According to the DC circuit breaker having the arc extinguishing device as described above, in addition to the effect of the first embodiment by unitizing the arc extinguishing device, the holding member 36 is provided with the positioning convex portion, and the circuit breaker case 2 The arc extinguishing device can be positioned by fitting the positioning convex portion into the positioning concave portion 39 formed on the side. Therefore, the installation work of the arc extinguishing device becomes very easy.
Further, since the openings of the magnet holding portions 29 and 29 are covered by the yoke 38, the permanent magnet 25 can be prevented from falling off from the magnet holding portion 29.

  The DC circuit breaker according to the present invention is not limited to the aspect of the above embodiment, and the gist of the present invention is not limited to the overall structure of the DC circuit breaker but also the structure of the arc extinguishing device and the like. As long as it does not deviate, it can change suitably as needed.

For example, in the above embodiment, two fixed contacts and two movable contacts are provided in one electric circuit, but the arc extinguishing apparatus according to the present invention has one fixed contact and one movable contact in one electric circuit. The present invention can also be suitably applied to a type of DC breaker that is provided only one by one.
Moreover, in the said embodiment, although the magnet holding | maintenance part is made into the to-be-engaged part, the engagement protrusion as an engaging part is provided in an arc-extinguishing board, the engagement hole as an to-be-engaged part is provided in a holding member, etc. The design of the arc extinguishing plate and the holding member can be appropriately changed.
Furthermore, regarding the positioning of the arc extinguishing plate, the grid, the permanent magnet, the arc running part, and the contact part, the position of the above embodiment is only an example of a suitable position, and the position at which each element is arranged. The design can be changed.

  Furthermore, in providing the positioning convex portion on the holding member, it is possible to provide the positioning convex portion with the configuration shown in FIG. 9 in addition to the configuration described in the second embodiment. For example, in FIG. 9A, a holding member similar to the holding member 26 of the first embodiment is used, and a positioning projection 51 protruding downward is formed on the bottom surface of the yoke 38 by bending. . That is, no positioning protrusion is provided on the holding member. Even if such a configuration is adopted, it is possible to achieve the same effect as the DC circuit breaker described in the second embodiment that the installation work of the arc extinguishing device is simplified. Moreover, as shown in FIG.9 (b), it can change a design suitably about where the positioning convex part 51 is provided. Furthermore, as shown in FIG. 9C, there is no problem even if the holding member 26 is covered with the two yokes 38A and 38B. In addition, as shown in FIG. 9 (d), a convex portion 48 is provided on the circuit breaker case 2 side, and a concave portion 47 into which the convex portion 48 is fitted is provided on the holding member 46 side, thereby positioning the arc extinguishing device. There is no problem.

Furthermore, in the second embodiment, a screw hole is provided in the positioning recess and the arc extinguishing device is screwed. However, it is possible to appropriately change how the arc extinguishing device is fixed. .
In addition, in the second embodiment, as in the first embodiment, the arc extinguishing plate and the holding member are engaged, but the arc extinguishing plate and the holding member do not have to be integrated. That is, by making it possible to easily fix the holding member provided with the contact holding part and the magnet holding part, it is easy to install at least the permanent magnet, the yoke, and the first fixing bracket. The above-described problem of facilitating the above can be achieved.

  1 .... DC breaker 2 .... breaker case 3 .... power supply side terminal 4 .... load side terminal 5 .... first fixed contact (fixed contact, contact part) 6, ... first fixing bracket , 9 .. First movable contact (movable contact, contact part), 11 .. Movable contact member, 17 .. Fixed contact part, 18 .. Arc traveling part, 21 .. Arc extinguishing device, 22. , 23 .. Arc extinguishing plate, 24 .. Grid, 25 .. Permanent magnet, 26, 36, 46 .. Holding member, 28 .. Contact holding portion, 29 .. Magnet holding portion, 38. .. Positioning recess (positioned engagement portion), 47 .. Concavity (positioning engagement portion), 48 .. Projection (positioned engagement portion), 51 .. Positioning projection (positioning engagement portion)

Claims (1)

A power supply side terminal is provided on the front side of the circuit breaker case, and a load side terminal is provided on the rear side. A fixed contact and a movable contact are provided on the electric circuit disposed between the power supply side terminal and the load side terminal. An arc extinguishing device is installed in an arc extinguishing chamber where the contact part is arranged, and when the abnormal current flows through the electric circuit, the contact part is opened to interrupt the electric circuit. A DC circuit breaker,
While the fixed contact is provided on the surface of the metal plate-like fixed contact portion,
The arc extinguishing device includes a pair of arc extinguishing plates that are attached so as to sandwich the contact portion from right and left, a plurality of grids that are stacked between the arc extinguishing plates, and a set that is attached to the left and right sides of the fixed contact. A permanent magnet,
Furthermore, a holding member that integrally includes a magnet holding portion that holds the permanent magnet and a contact holding portion into which the fixed contact portion can be inserted is provided, and the permanent magnet is attached to the magnet holding portion. The holding members holding the fixed contact portions respectively are covered with a yoke, a positioning engagement portion can be engaged with the yoke, and the positioning engagement portion can be engaged with the breaker case side. A DC circuit breaker characterized in that each part is provided.

Images