JP6879173B2 - Switchgear - Google Patents

Description

The present invention relates to a switchgear that conducts and cuts off an electric current.

In a conventional switchgear, when a pair of contacts are operated from a closed state to an open state in order to cut off an electric current, an arc discharge may occur between the pair of contacts. In this case, a magnetic field formed by a permanent magnet is applied to the arc discharge, and the arc discharge is stretched by the Lorentz force to extinguish the arc (for example, Patent Document 1).

JP 2015-888477

In a conventional switchgear, when the arc discharge is extinguished, the arc discharge is extended in the direction in which the permanent magnet is arranged, and a part of the arc discharge is stuck in the vicinity of the permanent magnet. At this time, there is a problem that the permanent magnet is demagnetized by the heat generated by the arc discharge, and the number of opening / closing operations of the switchgear is limited.

A switchgear according to the present invention, which has been made to solve these problems, can suppress demagnetization of a permanent magnet due to heat associated with arc discharge, and can improve the number of switchgear operations as compared with the conventional case. ..

The opening / closing device according to the present invention has an opening / closing mechanism having a pair of openable / closable contacts, a plate-shaped first magnetic material, and a surface opposite to the surface on one main surface side of the first magnetic material. A first side wall, which has a plate-shaped first insulator which is arranged so that the surface of the first insulator is directed to the side in the opening / closing direction of a pair of contacts, and a plate-shaped first side wall. It has two magnetic materials and a plate-shaped second insulator that is arranged on the side of one main surface of the second magnetic material with the surface opposite to the surface facing, and sandwiches a pair of contacts. It includes a second side wall arranged so that the surface of the first insulator and the surface of the second insulator face each other.
Further, the opening / closing device according to the present invention is arranged only on one side of the direction along the first side wall and the second side wall from the position of the pair of contact points, and is arranged on the side of the first magnetic material and the first magnetic material. A magnet that magnetizes the magnetic material 2 and forms a magnetic field in the space sandwiched between the first side wall and the second side wall is provided .
Due to the magnetic force of the magnetic field forming magnet, magnetic force lines are formed in the opposite directions in one direction at the positions of the pair of contacts, and on the surface of the first insulator, the direction from the first magnetic material to the first insulator. A magnetic force line is formed on the surface of the second insulator, and a magnetic force line is formed from the second magnetic material in the direction of the second insulator, or the magnetic force of the magnetic field forming magnet causes a pair of contact points. At the position, magnetic force lines are formed in one direction, and on the surface of the first insulator, magnetic force lines are formed from the first insulator to the direction of the first magnetic material, and on the surface of the second insulator. , field lines Ru is formed from the second insulator to the direction of the second magnetic body.

According to the present invention, by extending the arc discharge in a direction away from the arrangement position of the permanent magnet, it is possible to suppress the demagnetization of the permanent magnet due to the heat accompanying the arc discharge, and the opening / closing operation of the switchgear can be performed. The number of times can be improved. That is, it is possible to provide a switchgear having high reliability.

It is sectional drawing of the switchgear 100 or the switchgear 101 which concerns on Embodiment 1 of this invention. It is a top view of the arc extinguishing part 5 and the periphery of the switchgear 100 which concerns on Embodiment 1 of this invention. It is a perspective view of the arc extinguishing part 5 of the switchgear 100 or the switchgear 101 which concerns on Embodiment 1 of this invention. It is a top view which shows the direction of the magnetic field line of each part of the switchgear 100 which concerns on Embodiment 1 of this invention. It is a schematic diagram of the closed state of the movable contact 3 and the fixed contact 4 of the switchgear 100 which concerns on Embodiment 1 of this invention. FIG. 5 is a schematic view of an open state of a movable contact 3 and a fixed contact 4 of the switchgear 100 according to the first embodiment of the present invention. It is a figure which shows the trajectory of the arc discharge when the electric current of the arc discharge of the switchgear 100 which concerns on Embodiment 1 of this invention goes from the bottom of the paper surface to the top of the paper surface. It is a figure which shows the trajectory of the arc discharge when the electric current of the arc discharge of the switchgear 100 which concerns on Embodiment 1 of this invention goes from the paper surface to the bottom of the paper surface. It is a top view which shows the direction of the magnetic field line of each part of the switchgear 101 which concerns on Embodiment 1 of this invention. It is a figure which shows the trajectory of the arc discharge when the electric current of the arc discharge of the switchgear 101 which concerns on Embodiment 1 of this invention goes from the paper surface to the bottom of the paper surface. It is a figure which shows the trajectory of the arc discharge when the electric current of the arc discharge of the switchgear 101 which concerns on Embodiment 1 of this invention goes from the paper surface to the bottom of the paper surface. It is a figure which shows the plane of the arc extinguishing part 5c provided in the switchgear which concerns on Embodiment 2 of this invention, the direction of a magnetic field, and the trajectory of extension of an arc discharge. It is a figure which shows the plane of the arc extinguishing part 5d provided in the switchgear which concerns on Embodiment 2 of this invention, the direction of a magnetic field, and the trajectory of extension of an arc discharge. It is a figure which shows the plane of the arc extinguishing part 5e provided in the switchgear which concerns on Embodiment 3 of this invention, the direction of a magnetic field, and the trajectory of extension of an arc discharge. It is a figure which shows the plane of the arc extinguishing part 5f provided in the switchgear which concerns on Embodiment 4 of this invention, the direction of a magnetic field, and the trajectory of extension of an arc discharge. It is a figure which shows the plane of the arc extinguishing part 5g provided in the switchgear which concerns on Embodiment 5 of this invention, the direction of a magnetic field, and the trajectory of extension of an arc discharge. It is sectional drawing of the switchgear 102 which concerns on Embodiment 6 of this invention. It is a top view of the arc extinguishing part 5h and the periphery of the switchgear 102 which concerns on Embodiment 6 of this invention. It is sectional drawing of the arc extinguishing part 5j provided in the switchgear which concerns on Embodiment 7 of this invention. It is sectional drawing of the arc extinguishing part 5k provided in the switchgear which concerns on Embodiment 7 of this invention.

Embodiment 1.
1 to 11 show a first embodiment for carrying out the present invention.
First, the configuration of the switchgear 100 according to the first embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a cross-sectional view of the switchgear 100, and FIG. 2 is a plan view of the arc extinguishing portion 5 and its periphery from the direction of the arrow A shown in FIG. Further, FIG. 3 is a perspective view of the arc extinguishing portion 5.
Note that FIG. 1 also serves as a cross-sectional view of the switchgear 101 described in another embodiment 1 described later. In this case, the switchgear 101 has an arc extinguishing portion 5b built in instead of the arc extinguishing portion 5 built in the switchgear 100. Further, FIG. 3 also serves as a perspective view of the arc extinguishing portion 5b built in the switchgear 101.

With reference to FIG. 1, the case 1 made of an insulating resin or the like includes a movable contact 3, a fixed contact 4, an arc extinguishing portion 5, a first conductor 11, a second conductor 12, and a first. The terminal block 13, the second terminal block 14, and the connecting conductor 17 are built in.
Further, the inside of the case 1 is protected by covering the upper part of the case 1 with a cover 2 made of an insulating resin or the like.

The movable contact 3 is rotatably configured around a rotating shaft 32, and is composed of a pair of a movable contact 31 formed at one end of the movable contact 3 and a fixed contact 41 formed on the surface of the fixed contact 4. Make up the contacts of.
A drive mechanism unit and a relay unit (not shown) are arranged inside the case 1. The drive mechanism unit includes a mechanism for rotating the movable contact 3 around a rotating shaft 32 to open and close between the movable contact 31 and the fixed contact 41, and is movable by supplying electric power by the operation of the relay unit, which will be described later. The opening operation and the closing operation of the contact 31 and the fixed contact 41 are executed.

Further, the movable contact 3 is electrically connected to the connecting conductor 17. The connecting conductor 17 is electrically connected to the first conductor 11, and the first conductor 11 is electrically connected to the first terminal block 13. That is, the movable contact 31 of the movable contact 3 is electrically connected to the first terminal block 13.

On the other hand, the fixed contact 4 is electrically connected to the second conductor 12. The second conductor 12 is electrically connected to the second terminal block 14. That is, the fixed contact 41 of the fixed contact 4 is electrically connected to the second terminal block 14.

Generally, the switchgear 100 is used in a state where it is connected to a device such as an external power supply or a load to the first terminal block 13 and the second terminal block 14, respectively.
One terminal (not shown) of the wiring connected to one of the external devices is connected to the first terminal block 13. This terminal is arranged on the first terminal block 13, and the screw 15 is tightened and fixed to the first terminal block 13.
Similarly, one terminal (not shown) of the wiring connected to the other external device is connected to the second terminal block 14. This terminal is arranged on the second terminal block 14, and the screw 16 is tightened and fixed to the second terminal block 14.

Further, the fixed contact 41 is arranged in the space Ss between the first side wall 57 and the second side wall 58 constituting the arc extinguishing portion 5 described later, and the opening / closing direction between the movable contact 31 and the fixed contact 41 described later is , The direction is along the first side wall 57 and the second side wall 58.

Next, the structure of the arc extinguishing portion 5 will be described in detail with reference to FIGS. 2 and 3.
FIG. 2 shows a fixed contact 4 and an arc extinguishing portion 5. Further, the arc extinguishing portion 5 includes a first magnetic body 51, a second magnetic body 52, a first insulator 53, a second insulator 54, a first magnet 55, a second magnet 56, an arc extinguishing plate 59, and a case 551. , And case 561.

With reference to FIG. 2, the first magnetic material 51 is a plate-shaped magnetic material made of iron, cobalt, nickel or the like. On one main surface of the first magnetic body 51, a first insulator 53 formed of a plate-shaped heat-resistant and insulating ceramic or the like is arranged, and the first magnetic body 51 and the first insulator 53 are combined with each other. The first side wall 57 is formed by the above.

Like the first magnetic body 51, the second magnetic body 52 is a plate-shaped magnetic body made of iron, cobalt, nickel, or the like. On one main surface of the second magnetic body 52, a second insulator 54 made of ceramic or the like having plate-like heat resistance and insulating properties similar to the first insulator 53 is arranged, and the second magnetic body is arranged. The 52 and the second insulator 54 form a second side wall 58. The thickness tm indicates the plate thickness of the first magnetic body 51 and the second magnetic body 52.

The opening / closing direction of the fixed contact 41 and the movable contact 31, which will be described later, is substantially the vertical direction of the paper surface of FIG. 2, and the first side wall 57 has the surface 53f of the first insulator 53 lateral to the opening / closing direction. It is placed facing.
Further, the second side wall 58 is arranged so as to sandwich the fixed contact 41 and the movable contact 31, face the surface 54f of the second insulator 54, and face the first side wall 57. That is, the fixed contact 41 is arranged in the space Ss sandwiched between the first side wall 57 and the second side wall 58. The width Ws indicates the width of the space Ss.

Next, the position of the first magnet 55 and the position of the second magnet 56 will be described.
The direction a indicated by the arrow is one of the directions along the first side wall 57 and the second side wall 58. Further, the direction b indicated by the arrow is a direction along the first side wall 57 and the second side wall 58 in a direction opposite to the direction a.
Further, the alternate long and short dash line B is a line that is substantially perpendicular to the direction a and the direction b with the position of the fixed contact 41 as a base point and divides the switchgear 100 into two.
Further, the direction c indicated by the arrow is substantially perpendicular to the surface 53f of the first insulator 53, and indicates a direction from the first magnetic body 51 to the first insulator 53. Further, the direction d indicated by the arrow is substantially perpendicular to the surface 54f of the second insulator 54, and indicates a direction from the second magnetic body 52 to the second insulator 54.

The first magnet 55 formed of a permanent magnet is arranged on the back surface 51r of the first magnetic body 51 on the direction a side of the alternate long and short dash line B, and magnetizes the first magnetic body 51. Further, the arrow M1 indicates the magnetizing direction of the first magnet 55, which is substantially the same as the direction c. The first magnet 55 is covered with a case 551 to protect it from impact, moisture, and the like.
Similarly, the second magnet 56 formed of the permanent magnet is arranged on the back surface 52r of the second magnetic body 52 on the direction a side of the alternate long and short dash line B, and magnetizes the second magnetic body 52. Further, the arrow M2 indicates the magnetizing direction of the second magnet 56, which is substantially the same as the direction d. The second magnetic body 52 is covered with a case 561 in order to protect it from impact, moisture, and the like.
The arc extinguishing plate 59 composed of a plurality of metal plates is arranged near the end of the first side wall 57 and the second side wall 58 on the side in the direction b. In other words, the arc extinguishing portion 5 includes an arc extinguishing plate 59 on the side in the direction b. When the arc discharge described later extends to the outside of the space Ss, the arc discharge is extinguished by cooling the arc discharge and increasing the resistance.

Next, with reference to FIG. 4, the magnetic field formed by the first magnet 55 and the second magnet 56 will be described.
FIG. 4 is a plan view showing the direction of the magnetic field of each part of the switchgear 100 according to the first embodiment of the present invention, and shows a plan view from the same direction as in FIG. In the drawing, the description of the fixed contactor 4, the case 551, the case 561, and the arc extinguishing plate 59 is omitted.
Further, the solid line arrows shown in the space Ss and its vicinity indicate the direction of the magnetic field at the position in the figure.

First, the direction of the magnetic field in the vicinity of the surface 53f and the surface 53f of the first insulator 53 will be described.
The direction f72 of the magnetic field inside the region S571 shown by the dotted line in the vicinity of the first magnet 55 is the direction c. Further, in the region on the side of the direction a from the region S571, the direction of the magnetic field is the direction f71 in which the component of the direction a is superimposed on the component of the direction c. Further, in the region on the side of the direction b from the region S571, the direction of the magnetic field is the direction f73 in which the component of the direction b is superimposed on the component of the direction c.
Further, even inside the region S572 indicated by the dotted line on the side of the direction b from the alternate long and short dash line B, the direction of the magnetic field is the direction in which the component of the direction b is superimposed on the component of the direction c.

In other words, the magnetic field in the vicinity of the surface 53f and the surface 53f of the first insulator 53 is a direction in which the components of the direction a or the direction b are superimposed depending on the position and the first magnetic material 51 is directed toward the first insulator 53. ..

Further, the direction of the magnetic field in the vicinity of the surface 54f and the surface 54f of the second insulator 54 will be described.
The direction f82 of the magnetic field inside the region S581 shown by the dotted line in the vicinity of the second magnet 56 is the direction d. Further, in the region on the side of the direction a from the region S581, the direction of the magnetic field is the direction f81 in which the component of the direction a is superimposed on the component of the direction d. Further, the direction of the magnetic field on the side of the direction b from the region S581 is the direction f83 in which the component of the direction b is superimposed on the component of the direction d. Further, even inside the region S582 indicated by the dotted line on the side of the direction b from the alternate long and short dash line B, the direction of the magnetic field is the direction in which the component of the direction b is superimposed on the component of the direction d.

In other words, the magnetic field in the vicinity of the surface 54f and the surface 54f of the second insulator 54 is a direction in which the components of the direction a or the direction b are superimposed depending on the position and the second magnetic material 52 is directed toward the second insulator 54. ..

Further, the direction of the magnetic field in the position of the fixed contact 41 and the region S411 in the vicinity thereof is the direction b. Further, the direction of the magnetic field inside the region Ssc shown by the dotted line from the side of the direction b of the region S411 to the vicinity of the end of the first side wall 57 (and the second side wall 58) is the direction b.

In the region sandwiched between the region Ssc and the region S572, the component of the magnetic field in the direction c increases from the region Ssc toward the region S572.
Similarly, in the region sandwiched between the region Ssc and the region S582, the component of the magnetic field in the direction d increases from the region Ssc toward the region S582.

Further, the direction of the magnetic field in the region Sbs outside from the space Ss on the side of the direction b generally faces the direction b. Further, on the side of the direction d inside the region Sbs, the magnetic field component of the direction c is superimposed, and on the side of the direction c inside the region Sbs, the component of the magnetic field of the direction d is superimposed.

Next, the operation of the switchgear 100 according to the first embodiment will be described with reference to FIGS. 5 and 6. In the figure, the movable contactor 3 and the fixed contactor 4 are shown among the parts shown in FIG. FIG. 5 is a schematic view of the switchgear 100 and shows a closed state, and FIG. 6 is a schematic view of the switchgear 100 and shows an open state.

The closed state of the switchgear 100 will be described with reference to FIG.
The closed state of the switchgear 100 is a state in which the movable contact 3 is rotated around the rotation shaft 32 from the open state described later, and the movable contact 31 and the fixed contact 41 are in contact with each other. In the closed state, the movable contact 3 and the fixed contact 4 are electrically connected via the movable contact 31 and the fixed contact 41. When a voltage is applied between the first terminal block 13 and the second terminal block 14, a current flows between the movable contact 31 and the fixed contact 41.

Further, the open state of the switchgear 100 will be described with reference to FIG.
The open state of the switchgear 100 is a state in which the movable contact 3 is rotated around the rotation shaft 32 from the above-mentioned closed state, and the movable contact 31 and the fixed contact 41 are dissociated. In the open state, the movable contact 3 and the fixed contact 4 are electrically insulated from each other.

However, when a voltage is applied between the first terminal block 13 and the second terminal block 14 and a current flows between the movable contact 31 and the fixed contact 41, immediately after operating from the closed state to the open state, An arc discharge may occur between the movable contact 31 and the fixed contact 41.
Although the details will be described later, the Lorentz force acts on the arc discharge by the magnetic field formed by the first magnet 55 and the second magnet 56, and the arc discharge is stretched and extinguished.

Paths D1, D2, and D3 in the figure indicate the paths of the arc discharge after the lapse of time during which the arc discharge extends.
First, the arc discharge is extended to the path D1 between the movable contact 31 and the fixed contact 41, and is extended to the path D2 and the path D3 over time. In other words, the arc discharge is stretched in direction b. When the arc discharge is stretched and extinguished, the movable contact 3 and the fixed contact 4 are electrically insulated from each other.

Further, the opening / closing direction in the first embodiment includes all tangential directions of the trajectory e of the movable contact 31 when the movable contact 3 rotates around the rotation shaft 32.

Next, with reference to FIGS. 7 and 8, when an arc discharge occurs between the movable contact 31 and the fixed contact 41, a Lorentz force acts on the arc discharge and the arc discharge is extinguished. Will be described in detail.
7 and 8 show a plan view in the same manner as in FIG. FIG. 7 shows a case where the direction of the current due to the arc discharge is from below the paper surface to above the paper surface, and FIG. 8 shows a case where the direction of the current due to the arc discharge is from above the paper surface to below the paper surface.

First, a case where the direction of the electric current due to the arc discharge is from below the paper surface to above the paper surface will be described with reference to FIG. 7.
The position C11 indicates the initial position where the arc discharge is generated, and is generally the position above the fixed contact 41. The orbit K1 indicates an orbit in the extending direction of the arc discharge, and the position C12 indicates a position in the middle of the orbit K1.

Initially, it is assumed that the switchgear 100 is in the closed state, and a current flows from the second terminal block 14 to the first terminal block 13 via the movable contact 31 and the fixed contact 41.
After that, the switchgear 100 operates from the closed state to the open state according to a shutoff instruction from the outside. At this time, an arc discharge is generated at the position C11. The direction of the current due to the arc discharge is from below the paper surface to above the paper surface.
As described above, since the direction of the magnetic field is the direction b inside the region S411, the Lorentz force is perpendicular to the arc discharge in the direction F11 facing the second side wall 58 according to Fleming's left-hand rule. It works. Therefore, the initial arc discharge extends toward the second side wall 58.

Further, when the arc discharge extends outside the region of the region S411, the Lorentz force acts in the direction b of the arc discharge due to the influence of the component in the direction d of the magnetic field. That is, as shown at position C12, a Lorentz force acts in the direction F12. In other words, the arc discharge extends the trajectory K1 in the tracing direction b while being pressed against the second insulator 54. At this time, since the surface 54f of the second insulator 54 is exposed to an arc discharge accompanied by heat, the second insulator 54 needs to have heat resistance and insulating properties.
Depending on the length of extension of the arc discharge, the arc resistance, which is the resistance between both ends of the arc discharge, increases, the voltage between both ends of the arc discharge cannot be maintained, and the arc discharge is extinguished.

Next, with reference to FIG. 8, a case where the direction of the current due to the arc discharge is from the top of the paper to the bottom of the paper is shown.
Similar to FIG. 7, the position C11 indicates the initial position where the arc discharge is generated, and is generally the position above the fixed contact 41. The orbit K2 indicates an orbit in the extending direction of the arc discharge, and the position C22 indicates a position in the middle of the orbit K2.

Initially, it is assumed that the switchgear 100 is in the closed state, and a current flows from the first terminal block 13 to the second terminal block 14 via the movable contact 31 and the fixed contact 41.
After that, the switchgear 100 operates from the closed state to the open state according to a shutoff instruction from the outside. At this time, an arc discharge is generated at the position C11. The direction of the current due to the arc discharge is from the top of the paper to the bottom of the paper.
As described above, in the region S411, the direction of the magnetic field is the direction b. Therefore, according to Fleming's left-hand rule, the Lorentz force acts on the arc discharge in the direction F21 which is perpendicular to the direction b and faces the first side wall 57. .. Therefore, the initial arc discharge extends toward the first side wall 57.

Further, when the arc discharge extends to the outside of the region S411, the Lorentz force acts in the direction b of the arc discharge due to the influence of the component in the direction c of the magnetic field. That is, as shown at position C22, a Lorentz force acts in the direction F22. In other words, the arc discharge extends the trajectory K2 in the tracing direction b while being pressed against the first insulator 53.
Depending on the length of extension of the arc discharge, the arc resistance increases, the voltage between both ends of the arc discharge cannot be maintained, and the arc discharge is extinguished.

In the case of the switchgear 100, the arc extinguishing plate 59 is arranged at the destination where the arc discharge extends. If the arc discharge does not extinguish before reaching the arc extinguishing plate 59, the arc discharge collides with the arc extinguishing plate 59 and is cooled and extinguished.

In the switchgear 100, the arc discharge is extended to the first magnet 55 and the second magnet 56 in the direction away from each other to extinguish the arc. Therefore, the heat generated by the arc discharge demagnetizes the first magnet 55 and the second magnet 56. It becomes possible to suppress.

Next, the configuration of the switchgear 101 according to the first embodiment, which is different from the switchgear 100 described above, will be described with reference to FIGS. 1, 3, and 9 to 11.
As described above, FIG. 1 also serves as a cross-sectional view of the switchgear 100 and the switchgear 101. The switchgear 101 has a built-in arc extinguishing portion 5b. Further, FIG. 3 also serves as a perspective view of the arc extinguishing portion 5b built in the switchgear 101.

Further, since the magnetizing directions of the first magnet 55r and the second magnet 56r, which will be described later, are different from those of the first magnet 55 and the second magnet 56 of the switchgear 100, the switchgear 101 is also different from the switchgear 100 in terms of the magnetic field formed. ..

FIG. 9 is a plan view showing the direction of the magnetic field of each part of the switchgear 101 according to the first embodiment of the present invention. The solid arrows in and near the space Ss in the figure indicate the direction of the magnetic field as in FIG. FIG. 10 shows a case where the direction of the current due to the arc discharge is from below the paper surface to above the paper surface, and FIG. 11 shows a case where the direction of the current due to the arc discharge is from above the paper surface to below the paper surface.
Since the same symbols and the same symbols as those in FIGS. 1 to 8 in the drawings are the same as or equivalent to the switchgear 100, detailed description thereof will be omitted.

The configuration of the switchgear 101 will be described with reference to FIG.
The direction cr indicated by the arrow in the figure is substantially perpendicular to the surface 53f of the first insulator 53, and indicates a direction from the first insulator 53 to the first magnetic body 51. In other words, the direction cr is the direction opposite to the direction c. Further, the direction dr indicated by the arrow is substantially perpendicular to the surface 54f of the second insulator 54, and indicates a direction from the second insulator 54 to the second magnetic body 52. In other words, the direction dr is the direction opposite to the direction d.

The first magnet 55r of the switchgear 101 has the same or the same mounting position and material as the first magnet 55 of the switchgear 100, but the magnetizing direction is different. The arrow M1r indicates the magnetizing direction of the first magnet 55r, which is substantially the same as the direction cr.
Similarly, the second magnet 56r of the switchgear 101 has the same or the same mounting position and material as the second magnet 56 of the switchgear 100, but the magnetizing direction is different. The arrow M2r indicates the magnetizing direction of the second magnet 56r, which is substantially the same as the direction dr.

Next, the direction of the magnetic field in the vicinity of the surface 53f and the surface 53f of the first insulator 53 will be described.
The direction f72r of the magnetic field inside the region S571 shown by the dotted line in the vicinity of the first magnet 55r is the direction cr. Further, in the region on the side of the direction a from the region S571, the direction of the magnetic field is the direction f71 in which the component of the direction b is superimposed on the component of the direction cr. Further, in the region on the side of the direction b from the region S571, the direction of the magnetic field is the direction f73r in which the component of the direction a is superimposed on the component of the direction cr.
Further, even inside the region S572 indicated by the dotted line on the side of the direction b from the alternate long and short dash line B, the direction of the magnetic field is the direction in which the component of the direction a is superimposed on the component of the direction cr.

In other words, the magnetic field in the vicinity of the surface 53f and the surface 53f of the first insulator 53 is a direction in which the components of the direction a or the direction b are superimposed depending on the position and the first insulator 53 is directed toward the first magnetic body 51. ..

Next, the direction of the magnetic field in the vicinity of the surface 54f and the surface 54f of the second insulator 54 will be described.
The direction f82r of the magnetic field inside the region S581 shown by the dotted line in the vicinity of the second magnet 56r is the direction dr. Further, in the region on the side of the direction a from the region S581, the direction of the magnetic field is the direction f81r in which the component of the direction dr is superimposed on the component of the direction dr. Further, the direction of the magnetic field on the side of the direction b from the region S581 is the direction f83r in which the component of the direction a is superimposed on the component of the direction dr. Further, even inside the region S582 indicated by the dotted line on the side of the direction b from the alternate long and short dash line B, the direction of the magnetic field is the direction in which the component of the direction a is superimposed on the component of the direction dr.

In other words, the magnetic field in the vicinity of the surface 54f and the surface 54f of the second insulator 54r is a direction in which the components of the direction a or the direction b are superimposed depending on the position and the second insulator 54 is directed toward the second magnetic body 52. ..

Further, the direction of the magnetic field in the position of the fixed contact 41 and the region S411 in the vicinity thereof is the direction a. The direction of the magnetic field of the region Ssc shown by the dotted line from the side of the direction b of the region S411 to the vicinity of the end of the first side wall 57 (and the second side wall 58) is the direction a.

In the region sandwiched between the region Ssc and the region S572, the component of the magnetic field in the direction cr increases from the region Ssc toward the region S572.
Similarly, in the region sandwiched between the region Ssc and the region S582, the component of the magnetic field in the direction dr increases from the region Ssc toward the region S582.

Further, the direction of the magnetic field in the region Sbs outside from the space Ss on the side of the direction b generally faces the direction a. Further, on the side of the direction dr inside the region Sbs, the magnetic field component of the direction dr is superimposed, and on the side of the direction cr inside the region Sbs, the component of the magnetic field of the direction cr is superimposed.

Next, with reference to FIGS. 10 and 11, when an arc discharge occurs between the movable contact 31 and the fixed contact 41, a Lorentz force acts on the arc discharge and the arc discharge is extinguished. Will be described in detail.
First, a case where the direction of the electric current due to the arc discharge is from below the paper surface to above the paper surface will be described with reference to FIG.

Initially, it is assumed that the switchgear 101 is in the closed state, and a current flows from the second terminal block 14 to the first terminal block 13 via the movable contact 31 and the fixed contact 41.
After that, the switchgear 101 operates from the closed state to the open state according to a shutoff instruction from the outside. At this time, an arc discharge is generated at the position C11. The direction of the current due to the arc discharge is from below the paper surface to above the paper surface.
As described above, in the region S411, the direction of the magnetic field is the direction a. Therefore, according to Fleming's left-hand rule, the Lorentz force acts on the arc discharge in the direction F21r which is perpendicular to the direction a and faces the first side wall 57. To do. Therefore, the initial arc discharge extends toward the first side wall 57.

Further, when the arc discharge extends to the outside of the region S411, the Lorentz force acts in the direction b of the arc discharge due to the influence of the component of the direction cr of the magnetic field. That is, as shown at position C13, a Lorentz force acts in the direction F22r. In other words, the arc discharge extends the trajectory K2r in the tracing direction b while being pressed against the first insulator 53.
Depending on the length of extension of the arc discharge, the arc resistance increases, the voltage between both ends of the arc discharge cannot be maintained, and the arc discharge is extinguished.

Next, with reference to FIG. 11, a case where the direction of the current due to the arc discharge is from the top of the paper to the bottom of the paper is shown.
Initially, it is assumed that the switchgear 101 is in a closed state, and a current flows from the first terminal block 13 to the second terminal block 14 via the movable contact 31 and the fixed contact 41.
After that, the switchgear 101 operates from the closed state to the open state according to a shutoff instruction from the outside. At this time, an arc discharge is generated at the position C11. The direction of the current due to the arc discharge is from the top of the paper to the bottom of the paper.
As described above, in the region S411, the direction of the magnetic field is the direction a. Therefore, according to Fleming's left-hand rule, the Lorentz force acts on the arc discharge in the direction F11r which is perpendicular to the direction a and faces the second side wall 58. To do. Therefore, the initial arc discharge extends toward the second side wall 58.

Further, when the arc discharge extends to the outside of the region S411, the Lorentz force acts in the direction b of the arc discharge due to the influence of the component of the direction dr of the magnetic field. That is, as shown at position C23, a Lorentz force acts in the direction F12r. In other words, the arc discharge extends the trajectory K1r in the tracing direction b while being pressed against the first insulator 53.
Depending on the length of extension of the arc discharge, the arc resistance increases, the voltage between both ends of the arc discharge cannot be maintained, and the arc discharge is extinguished.

In the case of the switchgear 101, the arc extinguishing plate 59 is arranged at the destination where the arc discharge extends. If the arc discharge does not extinguish before reaching the arc extinguishing plate 59, the arc discharge collides with the arc extinguishing plate 59 and is divided and extinguished.

That is, similarly to the switchgear 100, the switchgear 101 extends the arc discharge to the first magnet 55r and the second magnet 56r in the direction away from the arc discharge and extinguishes the arc. It is possible to suppress demagnetization with the second magnet 56r.

As described above, according to the first embodiment, it is possible to suppress the demagnetization of the first magnet and the second magnet due to the heat generated by the arc discharge. That is, the number of opening / closing operations of the switchgear can be improved, and a switchgear having high reliability can be provided.

Embodiment 2.
In the second embodiment, a mode in which the attracting magnet 61 is provided in order to promote the extension of the arc discharge will be described. Further, in another second embodiment, a mode including the attraction rod 64 will be described.
By arranging the attracting magnet 61 and the attracting rod 64, the extension of the arc discharge can be promoted and the arc discharge can be extinguished rapidly.

FIG. 12 is a plan view of the arc extinguishing portion 5c included in the switchgear of the second embodiment, and shows the locus of the direction in which the arc discharge is extended when the arc discharge occurs, and the direction of the magnetic field.
The switchgear provided with the arc extinguishing portion 5c is substantially the same as the switchgear 100, and the arc extinguishing portion 5c is arranged in place of the arc extinguishing portion 5.
Further, since the same symbols and the same symbols as those in FIGS. 1 to 11 in the drawings are the same as or equivalent to those in the first embodiment, detailed description thereof will be omitted.
Similarly, the solid arrows in and near the space Ss in the figure indicate the direction of the magnetic field. Further, as in FIG. 7, the case where the direction of the electric current due to the arc discharge is from below the paper surface to above the paper surface is shown.

The arc extinguishing portion 5c includes a first magnetic body 51, a second magnetic body 52, a first insulator 53, a second insulator 54, a first magnet 55, a second magnet 56, a case 551, a case 561, and a reference magnet. Includes 61 and case 661.

First, the structure of the arc extinguishing portion 5c will be described in detail with reference to FIG.
The attracting magnet 61 is arranged outside the space Ss on the side of the direction b. In other words, the arc extinguishing portion 5c is provided with an inviting magnet 61 on the side in the direction b.
Further, the arrow Ma indicates the magnetizing direction of the attracting magnet 61, which is substantially the same as the direction b. The attracting magnet 61 is covered with a heat-resistant and insulating ceramic case 611 in order to protect it from heat and current due to arc discharge.

Further, the operation of the attracting magnet 61 will be described.
By installing the attracting magnet 61, the strength of the magnetic field is enhanced. In particular, since the strength of the magnetic field on the side of the alternate long and short dash line B of the space Ss is increased, the generated arc discharge follows the orbit K1 and is rapidly extended. That is, the arc discharge can be extinguished rapidly.

FIG. 13 is a plan view of the arc extinguishing portion 5d provided in another switchgear of the second embodiment, showing a locus in a direction in which the arc discharge is extended when an arc discharge occurs, and a direction of a magnetic field. ..
The switchgear provided with the arc extinguishing portion 5d is substantially the same as the switchgear 100, and the arc extinguishing portion 5d is arranged in place of the arc extinguishing portion 5.

Further, since the same symbols and the same symbols as those in FIGS. 1 to 11 in the drawings are the same as or equivalent to those in the first embodiment, detailed description thereof will be omitted.
Similarly, the solid arrows in and near the space Ss in the figure indicate the direction of the magnetic field. Further, as in FIG. 7, the case where the direction of the electric current due to the arc discharge is from below the paper surface to above the paper surface is shown.

The arc extinguishing portion 5d includes a first magnetic body 51, a second magnetic body 52, a first insulator 53, a second insulator 54, a first magnet 55, a second magnet 56, a case 551, a case 561, and an attracting rod 64. , And case 641.

First, the structure of the arc extinguishing portion 5d will be described in detail with reference to FIG.
The attracting rod 64 has a structure in which the attracting magnetic body 63 is connected to the main surface of the attracting magnet 62. In addition, the attract rod 64 is covered with a heat-resistant and insulating ceramic case 641 to protect against heat and current from arc discharge.

Further, the portion including the tip of the attracting magnetic body 63 constituting the attracting rod 64 is located inside the space Ss on the side of the direction b, between the attracting magnetic body 63 and the first insulator 53, and the attracting magnetism. A space in which the arc discharge is extended is provided between the body 63 and the second insulator 54, and other portions constituting the attracting rod 64 are installed outside the space Ss on the side in the direction b. In other words, the arc extinguishing portion 5d includes an attracting rod 64 on the side in the direction b. The arrow Ma indicates the magnetizing direction of the attracting magnet 62 like the attracting magnet 61, and is substantially the same as the direction b.

Next, the action of the attraction rod 64 will be described.
By installing the attraction rod 64, the strength of the magnetic field is enhanced. In particular, since the strength of the magnetic field on the side of the alternate long and short dash line B of the space Ss is increased, the generated arc discharge follows the orbit K1 and is rapidly extended. That is, the arc discharge can be extinguished rapidly.

As described above, according to the second embodiment, the arc discharge can be rapidly extinguished. Further, as in the first embodiment, it is possible to suppress the demagnetization of the first magnet and the second magnet due to the heat generated by the arc discharge. That is, the number of opening / closing operations of the switchgear can be improved, and a switchgear having high reliability can be provided.

Embodiment 3.
In the first and second embodiments, a mode including two permanent magnets, a first magnet and a second magnet, has been described. In the third embodiment, a mode including one permanent magnet having only a third magnet will be described. Since the number of permanent magnets is one, the switchgear shown in the third embodiment can shorten the manufacturing time and reduce the manufacturing cost as compared with the switchgear shown in the first embodiment.

FIG. 14 is a plan view of the arc extinguishing portion 5e included in the switchgear of the third embodiment, and shows the locus of the direction in which the arc discharge is extended when the arc discharge occurs, and the direction of the magnetic field.
The switchgear provided with the arc extinguishing portion 5e is substantially the same as the switchgear 100, and the arc extinguishing portion 5e is arranged in place of the arc extinguishing portion 5.

Further, since the same symbols and the same symbols as those in FIGS. 1 to 11 in the drawings are the same as or equivalent to those in the first embodiment, detailed description thereof will be omitted.
Similarly, the solid arrows in and near the space Ss in the figure indicate the direction of the magnetic field. Further, as in FIG. 7, the case where the direction of the electric current due to the arc discharge is from below the paper surface to above the paper surface is shown.

The arc extinguishing portion 5e includes a first magnetic body 51, a second magnetic body 52, a first insulator 53, a second insulator 54, a third magnet 74, a third magnetic body 71, a third insulator 72, and a case. Includes 741.

The structure of the arc extinguishing portion 5e will be described in detail with reference to FIG.
The third magnetic body 71 is connected to the end portion of the first magnetic body 51 on the direction b side and the end portion of the second magnetic body 52 on the direction a side. The third magnetic body 71 is a plate-shaped magnetic body made of iron, cobalt, nickel, or the like, like the first magnetic body 51 and the second magnetic body 52.
Further, on the surface of the third magnetic body 71 on the direction b side, a third insulator 72 formed of a plate-shaped heat-resistant and insulating ceramic or the like is arranged, and the third magnetic body 71 and the third magnetic body 71 are arranged. The insulator 72 constitutes the third side wall 73.

Further, the third magnet 74 is arranged on the back surface 71r of the third magnetic body 71. The third magnet 74 is covered with a case 741 to protect it from impact, moisture, and the like. Further, the arrow M3 indicates the magnetizing direction of the third magnet 74, which is substantially the same as the direction b.

Next, the magnetic field formed by the third magnet 74 will be described.
The direction of the magnetic field in the vicinity of the surface 53f and the surface 53f of the first insulator 53 is the direction in which the component in the direction b is superimposed on the component in the direction c. In other words, the magnetic field in the vicinity of the surface 53f and the surface 53f of the first insulator 53 is the direction in which the components in the direction b are superimposed and directed from the first magnetic body 51 to the first insulator 53.

Further, the direction of the magnetic field in the vicinity of the surface 54f and the surface 54f of the second insulator 54 is the direction in which the component in the direction b is superimposed on the component in the direction d. In other words, the magnetic field in the vicinity of the surface 54f and the surface 54f of the second insulator 54 is the direction in which the components in the direction b are superimposed and directed from the second magnetic material 52 to the second insulator 54.

Further, the direction of the magnetic field in the vicinity of the surface 72f and the surface 72f of the third insulator 72 is generally the direction b. In other words, the magnetic field in the vicinity of the surface 72f and the surface 72f of the third insulator 72 is in the direction from the third magnetic material 71 to the third insulator 72.

Further, the position of the fixed contact 41 (not shown) and the direction of the magnetic field in the region S411 in the vicinity thereof are the direction b. Further, the direction of the magnetic field of the region Ssc from the side of the direction b of the region S411 to the vicinity of the end of the first side wall 57 (and the second side wall 58) is the direction b.

In the region sandwiched between the region Ssc and the surface 53f of the first insulator 53, the component of the magnetic field in the direction c increases from the region Ssc toward the surface 54f of the second insulator 54.
Similarly, in the region sandwiched between the region Ssc and the surface 54f of the second insulator 54, the component of the magnetic field in the direction d increases from the region Ssc toward the region S582.

Further, the direction of the magnetic field in the region Sbs outside from the space Ss on the side of the direction b generally faces the direction b. Further, on the side of the direction d inside the region Sbs, the magnetic field component of the direction c is superimposed, and on the side of the direction c inside the region Sbs, the component of the magnetic field of the direction d is superimposed.

In other words, the side of the direction b from the alternate long and short dash line B of the arc extinguishing portion 5e provided in the switch of the third embodiment has a magnetic field direction substantially similar to that of the arc extinguishing portion 5 of the first embodiment.
Further, as in the first embodiment, when an arc discharge occurs, the arc discharge follows the orbit K1 and is extended. That is, the arc discharge can be extinguished.

As described above, according to the third embodiment, since the number of permanent magnets is one, the manufacturing time can be shortened and the manufacturing cost can be reduced as compared with the switchgear shown in the first embodiment. ..

Further, as in the first embodiment, the arc discharge can be extinguished, and further, demagnetization with the third magnet due to heat accompanying the arc discharge can be suppressed. That is, the number of opening / closing operations of the switchgear can be improved, and a switchgear having high reliability can be provided.

Embodiment 4.
In the first and second embodiments, a mode including two permanent magnets, a first magnet and a second magnet, has been described. Further, in the third embodiment, a mode including one permanent magnet having only a third magnet has been described. In the fourth embodiment, a mode including three permanent magnets, a first magnet, a second magnet, and a third magnet, will be described.
A strong magnetic field can be formed by the first magnet, the second magnet, and the third magnet to promote the extension of the arc discharge and rapidly extinguish the arc discharge.

FIG. 15 is a plan view of the arc extinguishing portion 5f included in the switchgear of the fourth embodiment, and shows the trajectory in the direction in which the arc discharge is extended when the arc discharge occurs, and the direction of the magnetic field.
The switchgear provided with the arc extinguishing portion 5f is substantially the same as the switchgear 100, and the arc extinguishing portion 5f is arranged in place of the arc extinguishing portion 5.

Further, since the same symbols and the same symbols as those in FIGS. 1 to 11 and 14 in the drawings are the same as or equivalent to those of the first and third embodiments, detailed description thereof will be omitted.
Similarly, the solid arrows in and near the space Ss in the figure indicate the direction of the magnetic field. Further, as in FIG. 7, the case where the direction of the electric current due to the arc discharge is from below the paper surface to above the paper surface is shown.

The arc extinguishing portion 5f includes a first magnetic body 51, a second magnetic body 52, a first insulator 53, a second insulator 54, a first magnet 55, a second magnet 56, a third magnet 74, and a third magnetic body. Includes 71, third insulator 72, and case 741.

The magnetic field formed by the first magnet 55, the second magnet 56, and the third magnet 74 will be described.
The direction of the magnetic field in the vicinity of the surface 53f and the surface 53f of the first insulator 53 is the direction in which the component in the direction b is superimposed on the component in the direction c. In other words, the magnetic field in the vicinity of the surface 53f and the surface 53f of the first insulator 53 is the direction in which the components in the direction b are superimposed and directed from the first magnetic body 51 to the first insulator 53.

Further, the direction of the magnetic field in the vicinity of the surface 54f and the surface 54f of the second insulator 54 is the direction in which the component in the direction b is superimposed on the component in the direction d. In other words, the magnetic field in the vicinity of the surface 54f and the surface 54f of the second insulator 54 is the direction in which the components in the direction b are superimposed and directed from the second magnetic material 52 to the second insulator 54.

Further, the direction of the magnetic field in the vicinity of the surface 72f and the surface 72f of the third insulator 72 is generally the direction b. In other words, the magnetic field in the vicinity of the surface 72f and the surface 72f of the third insulator 72 is in the direction from the third magnetic material 71 to the third insulator 72.

Further, the position of the fixed contact 41 (not shown) and the direction of the magnetic field in the region S411 in the vicinity thereof are the direction b. Further, the direction of the magnetic field of the region Ssc from the side of the direction b of the region S411 to the vicinity of the end of the first side wall 57 (and the second side wall 58) is the direction b.

In the region sandwiched between the region Ssc and the surface 53f of the first insulator 53, the component of the magnetic field in the direction c increases from the region Ssc toward the surface 53f of the first insulator 53.
Similarly, in the region sandwiched between the region Ssc and the surface 54f of the second insulator 54, the component of the magnetic field in the direction d increases from the region Ssc toward the surface 54f of the second insulator 54.

Further, the direction of the magnetic field in the region Sbs outside from the space Ss on the side of the direction b generally faces the direction b. Further, on the side of the direction d inside the region Sbs, the magnetic field component of the direction c is superimposed, and on the side of the direction c inside the region Sbs, the component of the magnetic field of the direction d is superimposed.

That is, the direction of the magnetic field of the arc extinguishing portion 5f included in the switch of the fourth embodiment has substantially the same direction of the magnetic field as that of the third embodiment.
Further, by providing three permanent magnets of the first magnet 55, the second magnet 56, and the third magnet 74, the strength of the magnetic field is enhanced. In particular, since the strength of the magnetic field on the side of the alternate long and short dash line B of the space Ss is increased, the generated arc discharge follows the orbit K1 and is rapidly extended. That is, the arc discharge can be extinguished rapidly.

Further, as in the first embodiment, it is possible to suppress demagnetization of the first magnet, the second magnet, and the third magnet due to heat accompanying the arc discharge. That is, the number of opening / closing operations of the switchgear can be improved, and a switchgear having high reliability can be provided.

Embodiment 5.
In the fifth embodiment, the first magnetic body 51b and the second magnetic body 52b will be described with a structure having a bent portion (bent portion 51 bc, bent portion 52 bc) on the side of the direction b.
With this structure, the magnetic resistance of the magnetic circuit formed between the first magnetic body 51b and the first magnet 55 can be reduced, and similarly, the end portion 52be of the second magnetic body 52b can be formed on the second magnet 56. The magnetic resistance of the magnetic circuit formed between them can be reduced. As a result, the magnetic flux density leaking from the magnetic material can be maintained high even at the extension destination (direction b) of the arc, the extension of the arc discharge can be promoted, and the arc discharge can be extinguished rapidly.

FIG. 16 is a plan view of the arc extinguishing portion 5g included in the switchgear of the fifth embodiment, and shows the locus of the direction in which the arc discharge is extended when the arc discharge occurs, and the direction of the magnetic field.
The switchgear provided with the arc extinguishing portion 5g is substantially the same as the switchgear 100, and it is assumed that the arc extinguishing portion 5g is arranged in place of the arc extinguishing portion 5.

Further, since the same symbols and the same symbols as those in FIGS. 1 to 11 in the drawings are the same as or equivalent to those in the first embodiment, detailed description thereof will be omitted.
Similarly, the solid arrows in and near the space Ss in the figure indicate the direction of the magnetic field. Further, as in FIG. 7, the case where the direction of the electric current due to the arc discharge is from below the paper surface to above the paper surface is shown.

The structure of the arc extinguishing portion 5g will be described in detail with reference to FIG.
The portion of the first magnetic body 51b surrounded by the dotted line indicates the curved portion 51bc of the first magnetic body 51b. At the position of the curved portion 51bc, the first magnetic body 51b is bent in the direction opposite to the direction c, and the end portion 51be of the first magnetic body 51b is close to the first magnet 55. In other words, the end portion 51be is set so as to be closer to the first magnet 55 than the curved portion 51bc position.
Similarly, the portion of the second magnetic body 52b surrounded by the dotted line indicates the curved portion 52bc of the second magnetic body 52b. At the position of the curved portion 52bc, the second magnetic body 52b is bent in the direction opposite to the direction d, and the end portion 52be of the second magnetic body 52b is close to the second magnet 56. In other words, the end portion 52be is set so as to be closer to the second magnet 56 than the curved portion 52bc position.

When the end portion 51be and the first magnet 55 are close to each other, the magnetic resistance of the magnetic circuit formed between the first magnetic body 51b and the first magnet 55 can be reduced. Similarly, when the end portion 52be and the second magnet 56 are close to each other, the magnetic resistance of the magnetic circuit formed between the first magnetic body 51b and the second magnet 56 can be reduced. As a result, the magnetic flux density leaking from the magnetic material can be maintained high even at the extension destination (direction b) of the arc. Therefore, when an arc discharge occurs, the extension of the arc discharge can be promoted and the arc discharge can be extinguished rapidly.

Further, a configuration for increasing the magnetic flux density of the space Ss will be described.
The distance between the end portion 51be and the back surface 55n of the first magnet 55 (the surface opposite to the surface facing the first magnetic body 51b) is Lm1, and the distance between the end portion 52be and the back surface 56n of the second magnet 56 (second magnetic material) is set to Lm1. The distance between the 52b and the surface opposite to the surface facing the 52b) is defined as the interval Lm2. Further, the distance between the first magnetic material 51b and the second magnetic material 52b is defined as the distance Lb.
The interval Lb is set to be longer than the interval Lm1 and the interval Lm2. As a result, the interference between the magnetic field formed by the first magnet 55 and the magnetic field formed by the second magnet 56 can be reduced, so that the magnetic flux density of the space Ss can be formed more stably. Therefore, when an arc discharge occurs, the extension of the arc discharge can be further promoted and the arc discharge can be extinguished rapidly.

As described above, according to the fifth embodiment, the arc discharge can be rapidly extinguished. Further, as in the first embodiment, it is possible to suppress the demagnetization of the first magnet and the second magnet due to the heat generated by the arc discharge. That is, the number of opening / closing operations of the switchgear can be improved, and a switchgear having high reliability can be provided.

Embodiment 6.
In the first to fifth embodiments, a switchgear in which a pair of contacts is formed by a movable contact 31 and a fixed contact 41 and an opening / closing operation is executed by the pair of contacts has been described.
In the sixth embodiment, a mode in which two contacts are provided and these contacts are opened and closed at the same time will be described.

FIG. 17 is a cross-sectional view of the switchgear 102 of the sixth embodiment, and FIG. 18 is a plan view of the arc extinguishing portion 5h and its surroundings from the direction of arrow A2 shown in FIG.
Further, since the same symbols and the same symbols as those in FIGS. 1 to 11 in the drawings are the same as or equivalent to those in the first embodiment, detailed description thereof will be omitted.

The structure of the switchgear 102 will be described with reference to FIG.
The electromagnetic drive control unit 81 is built in the case 1b and the case 1c made of an insulating resin or the like. The electromagnetic drive control unit 81 is connected to one end of an insulating rod 82 made of an insulating material, and includes a mechanism for moving the insulating rod 82 up and down.
Further, the insulating rod 82 penetrates the case 1c, and the other end of the insulating rod 82 is connected to the movable contact 3b.

The movable contact 3b includes a movable contact 31b at one end and a movable contact 31c at the other end. That is, the movable contact 31b and the movable contact 31c are electrically connected. The fixed contact 4b has a fixed contact 41b at one end thereof, and the fixed contact 4c has a fixed contact 41c at one end thereof.
The movable contact 31b and the fixed contact 41b form a pair of contacts, and similarly, the movable contact 31c and the fixed contact 41c form a pair of contacts. That is, the two pairs of contacts are provided with a mechanism that simultaneously moves from the open state to the closed state and simultaneously operates from the closed state to the open state by moving the insulating rod 82 up and down.

The arc extinguishing portion 5h includes a first magnetic body 51, a second magnetic body 52, a first insulator 53, a second insulator 54, a first magnet 55, and a second magnet 56. Further, by covering the upper part of the case 1c with a cover 2b made of an insulating resin or the like, the arc extinguishing portion 5h, the fixed contact 41b, the fixed contact 4c, and the insulating rod 82 are protected.

Next, with reference to FIG. 18, the structure of the arc extinguishing portion 5h and its surroundings will be described in detail.
The opening / closing direction of the fixed contact 41b and the movable contact 31b and the opening / closing direction of the fixed contact 41c and the movable contact 31c are substantially up and down the paper surface of FIG. 18, and the first side wall 57 is the surface of the first insulator 53. 53f is arranged toward the side in these opening / closing directions.
Further, the second side wall 58 is arranged so as to sandwich the fixed contact 41b and the movable contact 31b, and the fixed contact 41c and the movable contact 31c, to face the surface 54f of the second insulator 54, and to face the first side wall 57. ..

Next, the position of the first magnet 55 and the position of the second magnet 56 will be described.
The alternate long and short dash line B1 is substantially perpendicular to the direction a and the direction b with the position of the fixed contact 41b as the base point. Similarly, the alternate long and short dash line B2 is substantially perpendicular to the direction a and the direction b with the position of the fixed contact 41c as the base point.

The first magnet 55 is arranged on the back surface 51r of the first magnetic body 51 on the side in the direction b from the alternate long and short dash line B1 and on the side in the direction a from the alternate long and short dash line B2, and magnetizes the first magnetic body 51. In other words, the first magnet 55 is arranged on the back surface 51r of the first magnetic body 51 between the alternate long and short dash line B1 and the alternate long and short dash line B2.
Similarly, the second magnet 56 is arranged on the back surface 52r of the second magnetic body 52 on the side in the direction b from the alternate long and short dash line B1 and on the side in the direction a from the alternate long and short dash line B2, and magnetizes the second magnetic body 52. In other words, the second magnet 56 is arranged on the back surface 52r of the second magnetic body 52 between the alternate long and short dash line B1 and the alternate long and short dash line B2.

The mechanism of the arc discharge generated between the fixed contact 41c and the movable contact 31c and the arc extinguishing mechanism of the arc discharge generated between the fixed contact 41b and the movable contact 31b will be described.
First, the mechanism of extinguishing the arc discharge generated between the fixed contact 41c and the movable contact 31c will be described.
In the space Ss from the periphery of the alternate long and short dash line B2 to the direction b, a magnetic field similar to the space Ss in the direction b from the periphery of the alternate long and short dash line B of the arc extinguishing portion 5 of the first embodiment is formed. Therefore, when an arc discharge occurs between the fixed contact 41c and the movable contact 31c, the arc discharge is extended in the direction b and extinguished.

Next, the mechanism of extinguishing the arc discharge generated between the fixed contact 41b and the movable contact 31b will be described.
In the space Ss from the periphery of the alternate long and short dash line B1 to the direction a, the magnetic field in the space Ss in the direction b from the periphery of the alternate long and short dash line B of the arc extinguishing portion 5 of the first embodiment is applied to the magnetic field that is line-symmetrical about the alternate long and short dash line B. Form. Therefore, when an arc discharge occurs between the fixed contact 41b and the movable contact 31b, the arc discharge is extended in the direction a and extinguished.

The case where the switchgear 102 operates from the closed state to the open state will be described.
It is assumed that the switchgear 102 is in the closed state, a voltage is applied between the fixed contact 4b and the fixed contact 41c, and a current flows from the fixed contact 4b in the direction of the fixed contact 41c.
Further, it is assumed that the switchgear 102 operates from the closed state to the open state in this state, and an arc discharge is generated between the fixed contact 41c and the movable contact 31c and between the fixed contact 41b and the movable contact 31b, respectively. ..
The arc discharge generated between the fixed contact 41c and the movable contact 31c is extended in the direction b and extinguished. Similarly, the arc discharge generated between the fixed contact 41b and the movable contact 31b is extended in the direction a and extinguished.
That is, since these arc discharges are stretched in opposite directions, they are extinguished without intersecting.

As in the first embodiment, the arc discharge is extended to the first magnet 55 and the second magnet 56 in the direction away from each other to extinguish the arc. Therefore, the heat associated with the arc discharge causes the first magnet 55 and the second magnet 56 to be extinguished. It is possible to suppress demagnetization with. That is, the number of opening / closing operations of the switchgear can be improved, and a switchgear having high reliability can be provided.

Embodiment 7.
In the seventh embodiment, a mode including an arc extinguishing plate 59c, a commutation plate 84, and an arc runner (83b, 83c) will be described in order to extinguish the arc efficiently and rapidly. Further, in another embodiment 7, a mode in which the arc extinguishing plate 59d having a shape different from that of the arc extinguishing plate 59c will be described.

FIG. 19 is a cross-sectional view of the arc extinguishing portion 5j and its periphery included in the switchgear of the seventh embodiment.
Further, since the same symbols and the same symbols as those in FIGS. 1 to 11 in the drawings are the same as or equivalent to those in the first embodiment, detailed description thereof will be omitted.
The direction f indicated by the arrow indicates a direction substantially perpendicular to the direction a, the direction b, the direction c, and the direction d, and the direction fr indicated by the arrow indicates a direction opposite to the direction f.

The configuration of the arc extinguishing portion 5j and its surroundings will be described with reference to FIG.
A pair of contacts is formed by a fixed contact 41 arranged at one end of the fixed contact 4d and a movable contact 31 arranged at one end of the movable contact 3c. The second side wall 58c is composed of a rectangular portion 58 cg and a wide portion 58 cw that is wider in the direction f and the direction fr than the rectangular portion 58 cg. Further, a first side wall 57c having substantially the same shape as the second side wall 58c is arranged at a position facing the second side wall 58c with the fixed contact 41 and the movable contact 31 interposed therebetween (not shown).

Further, the arc runner 83b made of the conductive member is arranged so that the flat plate portion 83bf of the arc runner 83b is substantially parallel to the direction f and substantially perpendicular to the direction b. The arc runner 83b is electrically connected to the fixed contact 4d.
Similarly, in the arc runner 83c made of the conductive member, the flat plate portion 83cf of the arc runner 83c is arranged so as to be substantially parallel to the direction fr and substantially perpendicular to the direction b. The arc runner 83c is electrically connected to the movable contact 3c.

Further, a gap 83 g is provided between the arc runner 83b and the arc runner 83c, and the gap 83 g is arranged between the first side wall 57c and the second side wall 58c. As will be described later, the arc discharge generated between the fixed contact 41 and the movable contact 31 is extended in the direction b through the gap 83 g.
Further, a commutation plate 84 made of a conductive material is arranged in the stretching direction (direction b) of the arc discharge. Further, the space Se surrounded by the dotted line between the commutation plate 84 and the arc runner 83b and the arc runner 83c is a space provided for expanding the arc discharge as described later, and the direction of the space Se. A multi-stage arc extinguishing plate 59b is arranged on the f side and the direction fr side.

Next, the arc extinguishing process of the arc discharge will be described.
When the contacts operate from the closed state to the open state, an arc discharge occurs between the fixed contact 41 and the movable contact 31. The arc discharge is stretched in the direction b, passes through the gap 83 g, and reaches the space Se. At the same time, the end of the arc discharge of the fixed contact 41 moves to the arc runner 83b, and the end of the arc discharge of the movable contact 31 moves to the arc runner 83c.

Further, the arc discharge is stretched, expanded in both directions f and fr, and stretched while contacting the arc extinguishing plate 59b. Further, when the arc discharge reaches the commutation plate 84, the commutation plate 84 and the arc discharge are short-circuited, and the arc discharge is rapidly divided by the arc extinguishing plate 59b due to the magnetic action generated from the electric circuit inside the commutation plate 84. It is cooled and the arc is extinguished.

As described above, according to the seventh embodiment, the arc discharge can be rapidly extinguished. Further, as in the first embodiment, it is possible to suppress the demagnetization of the first magnet and the second magnet due to the heat generated by the arc discharge. That is, the number of opening / closing operations of the switchgear can be improved, and a switchgear having high reliability can be provided.

Next, an arc extinguishing portion 5k provided in a switchgear different from that of the seventh embodiment described above will be described.
FIG. 20 is a cross-sectional view of the arc extinguishing portion 5k. Since the same symbols and the same symbols as those in FIGS. 1 to 11 and 19 in the drawings are the same as or equivalent to those in the first embodiment and the seventh embodiment described above, detailed description thereof will be omitted.

The arc extinguishing portion 5k and its surroundings will be described with reference to FIG.
The second side wall 58d is composed of a rectangular portion 58dg and a narrow end shaped portion 58dn having a shape in which the width of the direction f (and the direction fr) gradually decreases in the direction b. Further, a first side wall 57d having substantially the same shape as the second side wall 58d is arranged at a position facing the second side wall 58c with the fixed contact 41 and the movable contact 31 interposed therebetween (not shown).

The process of extinguishing the arc discharge is the same as that of the arc extinguishing portion 5j described above. Further, since the first side wall 57d and the second side wall 58d have a shape that gradually shrinks in the direction of the extension (direction b) of the arc discharge, the magnetic flux density can be maintained high even at the extension destination of the arc discharge. As a result, the speed at which the arc discharge is extended increases, and the arc can be quickly transferred to the commutation plate.
That is, the time until the arc discharge is divided and cooled by the arc extinguishing plate is shortened, and the effect of improving the reliability of interruption can be obtained.

As described above, according to the seventh embodiment, the arc discharge can be rapidly extinguished. Further, as in the first embodiment, it is possible to suppress the demagnetization of the first magnet and the second magnet due to the heat generated by the arc discharge. That is, the number of opening / closing operations of the switchgear can be improved, and a switchgear having high reliability can be provided.

Further, in the first to seventh embodiments, it has been described that the first insulator and the second insulator are formed of a ceramic or the like having heat resistance and insulating properties, but the first insulator and the first insulator have been described. The body may be molded from a polymer resin containing hydrogen.
When the arc discharge comes into contact with the first insulator or the second insulator, a part of the surface of the first insulator or the second insulator is vaporized, and hydrogen gas having high thermal conductivity is supplied. , The heat of the arc discharge is diffused in this hydrogen gas. That is, the effect of cooling and extinguishing this arc discharge can be obtained. Further, since cooling of each part of the arc extinguishing portion and contacts and the like is promoted, the effect of improving the insulation recovery of the space can be obtained.
Even if the case 611 and the case 641 according to the second embodiment are molded with a polymer resin containing hydrogen, the first insulator and the first insulator have the same effect as the case where the polymer resin containing hydrogen is used. can get.

Further, the first side wall and the second side wall may be configured so that the width Ws of the space Ss is gradually expanded in the extending direction of the arc discharge. According to this configuration, the hydrogen gas generated from the first insulator or the second insulator is injected in the direction orthogonal to the first side wall and the second side wall, so that the hydrogen gas can be generated in the extension direction of the arc discharge. Convection is generated, and the effect of extinguishing the arc discharge can be obtained.

Further, in the first to seventh embodiments, it is desirable that the thickness tm of the first magnetic material and the second magnetic material is 6 mm or less. In the case of tm thicker than 6 mm, when a magnet with a finite residual magnetic flux density is used, the magnetic flux density formed in the magnetic body is reduced to 1 tesla or less, and leakage occurs from the magnetic material surface near the position where the arc discharge occurs. There are cases where a sufficient Lorentz force cannot act on the arc discharge due to the magnetic flux density. Therefore, by setting the plate thickness of the magnetic material to 6 mm or less, it is possible to suppress a decrease in the magnetic flux density leaking from the surface of the magnetic material and improve the blocking reliability. Further, the first magnetic material and the second magnetic material can be improved. The thickness tm of the body may be gradually reduced from the position where the arc discharge is generated toward the extending direction of the arc discharge. According to this configuration, the magnetic flux inside the first magnetic body and the second magnetic body can be concentrated even at the extension destination of the arc discharge, so that the magnetic flux density leaking from the first magnetic body and the second magnetic body is increased. It can be maintained and the blocking reliability can be improved.

Further, in the second to seventh embodiments, the magnetizing direction of the first magnet is described only in the direction of the arrow M1 and the magnetizing direction of the second magnet is described only in the direction of the arrow M2. May be the direction of the arrow M1r, and the magnetizing direction of the second magnet may be the direction of the arrow M2r.
In this case, it is necessary that the magnetizing direction of the attracting magnet 61 and the attracting magnet 62 of the second embodiment is the opposite direction of the arrow Ma.

In the first to seventh embodiments, when the first magnet, the second magnet, and the third magnet are permanent magnets, the effect of the present invention is exhibited by the first magnet, the second magnet, and the second magnet due to the heat associated with the arc discharge. It was explained that it is possible to suppress demagnetization with three magnets. Even when the first magnet, the second magnet, and the third magnet are electromagnets, the first magnet, the second magnet, and the third magnet can suppress damage to the electromagnet due to heat generated by the arc discharge.

Further, in the present invention, each embodiment can be freely combined, and each embodiment can be appropriately changed or omitted within the scope of the invention.

The first magnetic material described in the first to seventh embodiments is an example of the first magnetic material described in the claims. Similarly, the first insulator is an example of the first insulator described in the claims, the first side wall is an example of the first side wall described in the claims, and the second magnetic material is an example of the first side wall described in the claims. , The second insulator is an example of the second insulator described in the claims, the second insulator is an example of the second insulator described in the claims, and the second side wall is described in the claims. It is an example of the second side wall, and the third magnetic material is an example of the third magnetic material described in the claims.
Further, the first magnet, the second magnet, and the third magnet are examples of magnets for forming a magnetic field described in the claims. Further, the first magnet is an example of the first magnet described in the claims, the second magnet is an example of the second magnet described in the claims, and the third magnet is an example of the patent claims. The third magnet described in the scope is an example, the curved portion 51bc is an example of the first curved portion described in the claims, and the curved portion 52bc is an example of the second curved portion described in the claims. It is an example.
Further, the movable contact and the fixed contact are examples of a pair of contacts described in the claims, and the movable contact and the fixed contact are examples of the opening / closing mechanism described in the claims.

3, 3b, 3c Movable contacts, 4, 4b, 4c Fixed contacts, 31, 31b, 31c Movable contacts, 41, 41b, 41c, 41d Fixed contacts, 51, 51b 1st magnetic material, 51bc Curved part, 52, 52b 2nd magnetic material, 52bc curved part, 53 1st insulator, 54 2nd insulator, 55, 55r 1st magnet, 56, 56r 2nd magnet, 57, 57b, 57c, 57d 1st side wall, 58, 58b , 58c, 58d 2nd side wall, 59, 59b Arc extinguishing plate, 61, 62 attracting magnet, 63 attracting magnetic material, 64 attracting rod, 71 3rd magnetic material, 100, 101, 102 switchgear.

Claims (18)

An opening / closing mechanism with a pair of openable / closable contacts,
It has a plate-shaped first magnetic material and a plate-shaped first insulator that is arranged so that the surface opposite to the surface faces the side of one main surface of the first magnetic material, and the pair. A first side wall, which is arranged so that the surface of the first insulator faces the side in the opening / closing direction of the contact.
It has a plate-shaped second magnetic material and a plate-shaped second insulator that is arranged so that the surface opposite to the surface faces the side of one main surface of the second magnetic material, and the pair. A second side wall, which is arranged so that the surface of the first insulator and the surface of the second insulator face each other with the contact point interposed therebetween.
Of the directions along the first side wall and the second side wall, the first magnetic body and the second magnetic body are arranged only on the side in one direction from the position of the pair of contact points. A magnet for forming a magnetic field, which is magnetized and forms a magnetic field in a space sandwiched between the first side wall and the second side wall, is provided .
Due to the magnetic force of the magnetic field forming magnet, magnetic force lines are formed in the opposite direction of the one direction at the positions of the pair of contact points, and on the surface of the first insulator, the first magnetic material to the first magnetic force. A magnetic force line is formed in the direction of the insulator 1, and on the surface of the second insulator, a magnetic force line is formed from the second magnetic material in the direction of the second insulator, or the magnetic force line is formed. Due to the magnetic force of the magnet, magnetic force lines are formed in one direction at the positions of the pair of contacts, and on the surface of the first insulator, the direction from the first insulator to the first magnetic body. to the magnetic field lines is formed, and wherein in the surface of the second insulator, switchgear according to claim Rukoto magnetic field lines are formed in the direction of the second magnetic body from said second insulator. The magnetic field forming magnet includes a first magnet connected to the other main surface of the first magnetic material and a second magnet connected to the other main surface of the second magnetic material. The switchgear according to claim 1, wherein the switchgear is characterized by the above. A third magnetic material connected to the one side of the first magnetic material and the one side of the second magnetic material with one main surface facing in the opposite direction of the one direction.
The switchgear according to claim 1 or 2 , further comprising a third magnet which is a magnet for forming a magnetic field connected to the other main surface of the third magnetic material. It has two sets of the pair of contacts,
One of the two sets of the pair of contacts and the other of the two sets of the pair of contacts are connected.
When the one pair of contacts operates from the open state to the closed state, the other pair of contacts operates from the open state to the closed state.
The switchgear according to claim 1 or 2, wherein when the one pair of contacts operates from the closed state to the open state, the other pair of contacts operates from the closed state to the open state. When one pair of contacts operates from a closed state to an open state, the other pair of contacts includes a plurality of plate-shaped arc-extinguishing plates in opposite directions of the one direction. The switchgear according to any one of claims 1 to 4. The switchgear according to any one of claims 1 to 4 , wherein an attracting magnet is provided in the direction opposite to one of the directions. Claims 1 to 4 , wherein an attracting magnet having an attracting magnet and an attracting rod having a rod-shaped magnetic material on the main surface of the attracting magnet in the one direction is provided in a direction opposite to the one direction. The opening / closing device according to any one item. The second magnetic material has a second curved portion that bends toward the other main surface side of the second magnetic material on the side opposite to the one direction, and the second magnetic material has a second curved portion that bends toward the other main surface side of the second magnetic material. 1. Any one of claims 1 to 7 , wherein the position of the tip end of the second curved portion is closer to the magnetic field forming magnet than the position of the second curved portion. The opening and closing device described in. The first magnetic material is directed to the side opposite to the one direction, and the thickness of the first magnetic material is reduced.
The second magnetic material is any one of claims 1 to 8 , characterized in that the thickness of the second magnetic material is reduced toward the side opposite to the one direction. The opening and closing device described. The first side wall has a first wide portion that is wider than the one direction on the side opposite to the one direction.
Any one of claims 1 to 9 , wherein the second side wall has a second wide portion having a width wider than that of the one direction on the side opposite to the one direction. The switchgear described in the section. The first side wall has a first narrow-shaped portion having a shape in which the width of the first side wall is reduced on the side opposite to the one direction.
Claims 1 to claim 1, wherein the second side wall has a second narrow-shaped portion having a shape in which the width of the second side wall is reduced on the side opposite to the one direction. 9. The switchgear according to any one of 9. The distance between the first side wall and the second side wall is directed to the side opposite to the one direction.
The switchgear according to any one of claims 1 to 11, wherein the switchgear is expanded. The switchgear according to any one of claims 1 to 12 , wherein the first magnetic material and the second magnetic material are composed of any one of iron, cobalt, and nickel. apparatus. The switchgear according to any one of claims 1 to 13 , wherein the thickness of the first magnetic material and the thickness of the second magnetic material are 6 mm or less. The switchgear according to any one of claims 1 to 14 , wherein the first insulator and the second insulator are made of ceramic. The switchgear according to any one of claims 1 to 14 , wherein the first insulator and the second insulator are made of a polymer resin containing hydrogen. The switchgear according to any one of claims 1 to 16 , wherein the magnetic field forming magnet is composed of a permanent magnet. The switchgear according to any one of claims 1 to 16 , wherein the magnetic field forming magnet is composed of an electromagnet.

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