JP2003031088A - Electromagnetic drive mechanism for switchgear - Google Patents

Abstract

(57) [Problem] To provide a compact and inexpensive electromagnetic drive mechanism for a switchgear. An electromagnetic drive mechanism for a switching device includes a movable shaft having a movable core portion and a movable shaft portion, a drive coil surrounding the movable core portion, and a movable core portion from both sides of the drive coil. 13, a first yoke 6 having a first A yoke 4 and a first B yoke 5, a first permanent magnet 7 provided at an end of the first A yoke 4, and a drive coil 3. A second yoke 10 having a second A yoke 8 and a second B yoke 9 toward the movable core 13 from both sides, and a second permanent magnet 11 provided at an end of the second A yoke 8 It has. The magnetic flux passing through the first magnetic path including the movable iron core 13 and the first yoke 6 by the first permanent magnet 7 and the movable iron core 1 by the second permanent magnet 11.
3 and the magnetic flux passing through the second magnetic path including the second yoke 10 passes through the movable core portion 13 in the opposite direction, and the magnetic flux is generated by energizing the drive coil 3 to increase one magnetic flux and the other magnetic flux. The movable core 13 is reciprocated by reducing the magnetic flux.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive mechanism for an opening / closing device, and more particularly to a drive mechanism utilizing electromagnetic force.

[0002]

2. Description of the Related Art FIG. 10 is a sectional view showing the structure of a conventional electromagnetic drive mechanism for a switchgear. In FIG. 10, an electromagnetic drive mechanism 101 for a switchgear includes a movable shaft 102 connected to a movable contact (not shown) that reciprocates to come into contact with and separate from a fixed contact (not shown), and surrounds the movable shaft 102. The annular upper drive coil 103 and the lower drive coil 104 provided, and the permanent magnet 105 provided between the upper drive coil 103 and the lower drive coil 104.
And a yoke 106 that slidably penetrates through the movable shaft 102 and surrounds the upper drive coil 103, the lower drive coil 104, and the permanent magnet 105.

The movable shaft 102 includes a movable iron core portion 107 that reciprocates on a common central axis of the upper drive coil 103 and the lower drive coil 104, and a movable iron core portion 107 that extends in the direction in which the movable iron core 107 reciprocates. Shaft 1
And 08. The movable core portion 107 is arranged in the yoke 106 so as to be capable of reciprocating. Movable shaft 1
Reference numeral 08 denotes a movable shaft through hole 106a provided in the yoke 106.
And is reciprocally moved together with the movable iron core portion 107.

The upper drive coil 103 is provided closer to the movable contact than the lower drive coil 104, and the movable iron core portion 107 and the movable shaft portion 108 are moved by energizing the upper drive coil 103 and the lower drive coil 104. The movable contact and the fixed contact are brought into contact with and separated from each other.
The upper drive coil 103 is provided so as to surround the upper side surface of the movable iron core portion 107, and the lower drive coil 104 is provided so as to surround the lower side surface of the movable iron core portion 107.

The permanent magnet 105 is arranged between the movable iron core portion 107 and the yoke 106 so that the same pole (for example, N pole) faces each other around the axis of the movable iron core portion 107. On the movable iron core 107 side of the permanent magnet 105, an internal yoke 110 is provided so as to face the side surface of the movable iron core 107, and forms a magnetic path through which the magnetic flux from the permanent magnet 105 passes.

The yoke 106 is formed by laminating a plurality of iron plates in a direction perpendicular to the direction in which the movable shaft 102 reciprocates. Therefore, in FIG. 10, only one of the iron plates is shown. The yoke 106 includes an upper side portion 106b on the upper drive coil 103 side and a lower drive coil 10 side.
4 side lower side part 106c, and upper side part 106b,
A movable shaft through hole 106a through which the movable shaft 102 penetrates is provided.

In FIG. 10, the movable core portion 107 has a yoke 106.
FIG. 9 is a diagram showing a state in which the fixed contact and the movable contact are in contact with the lower side portion 106c, that is, an opened state in which the fixed contact and the movable contact are apart from each other. Since the permanent magnets 105 are arranged in this manner, the permanent magnets 105, the inner yoke 110, the movable iron core portion 107, the upper side portion 1 are provided around the upper drive coil 103.
06b and the magnetic path shown by the dashed line passing through the side portions of the yoke 106 are formed, and around the lower drive coil 104, the permanent magnet 105, the internal yoke 110, the movable iron core portion 107, the lower side portion 106c and the yoke. A magnetic path indicated by a dashed line passing through the side portion of 106 is formed. In the magnetic path formed around the upper drive coil 103, the movable core portion 107 and the upper side portion 106b are provided.
And a gap 111, which is a space that is not seen in the magnetic path formed around the lower drive coil 104, exists, and since the magnetic resistance increases due to this gap 111, the magnetic flux from the permanent magnet 105 is increased. Most of them are lower drive coils that pass through the inner yoke 110 in the direction of the arrow toward the lower side portion 106c in the movable iron core portion 107 and return to the permanent magnet 105 through the lower side portion 106c and the side portions of the yoke 106. It passes through a magnetic path formed around 104. Therefore, the movable core portion 107 is held in the open state by being attracted to the lower side portion 106c by the magnetic flux passing through the magnetic path formed around the lower drive coil 106c.

When the upper drive coil 103 is energized, the upper drive coil 103 generates a magnetic flux in the same direction as the magnetic flux of the permanent magnet 105 passing through the magnetic path formed around the upper drive coil 103. When energized, the lower drive coil 104 is configured to generate a magnetic flux in the same direction as the magnetic flux of the permanent magnet 105 passing through the magnetic path formed around the lower drive coil 104.

Next, the operation will be described. The state in which the movable core portion 107 of FIG. 10 is attracted to the lower side portion 106c, that is, the closing operation from the open state to the closed state is performed as follows. First, the upper drive coil 103 is energized. Due to this energization, a magnetic flux is generated around the upper drive coil 103 in the same direction as the magnetic flux of the permanent magnet 105. The magnetic flux of the upper drive coil 103 is added to the magnetic flux of the permanent magnet 105, the magnetic flux in the magnetic path around the upper drive coil 103 becomes larger than the magnetic flux in the magnetic path around the lower drive coil 104, and the movable iron core portion 107 has a lower side portion. It moves away from 106c to the upper side portion 106b, and along with this, the movable shaft portion 108 and the movable contact also move toward the fixed contact.
When the movable core portion 107 reaches the upper side portion 106b and the movable contact comes into contact with the fixed contact to be in the closed state, the movable core portion 10
7 and the lower side portion 106c, a space gap is formed, and a gap exists in the magnetic path around the lower drive coil 104, and the magnetic resistance of this magnetic path increases. On the contrary, in the magnetic path around the upper drive coil 103, the movable iron core 107
Since the gap 111 that is a space between the upper side portion 106b and the upper side portion 106b is eliminated, the magnetic resistance is reduced. Therefore, even when the energization of the upper drive coil 103 is stopped, most of the magnetic flux of the permanent magnet 105 passes around the upper drive coil 103 having a small magnetic resistance, and the movable iron core portion 107 is attracted to the upper side portion 106b. Hold, and the closed state is maintained.

The opening operation from the closed state to the open state is performed based on the same principle as the closing operation. That is, first, the lower drive coil 104 is energized. Due to this energization, a magnetic flux is generated around the lower drive coil 104 in the same direction as the magnetic flux of the permanent magnet 105. The magnetic flux of the lower drive coil 104 is added to the magnetic flux of the permanent magnet 105, and the magnetic flux in the magnetic path around the lower drive coil 104 is added to the upper drive coil 1.
03, the movable core portion 107 moves away from the upper side portion 106b to the lower side portion 106c, and accordingly, the movable shaft portion 108 and the movable contact also move away from the fixed contact. . When the movable core portion 107 reaches the lower side portion 106c and returns to the open state, that is, the state of FIG. 10, a space gap 111 is formed between the movable core portion 107 and the upper side portion 106b, and the magnetic field around the upper drive coil 103 is formed. The presence of the gap 111 in the path increases the magnetic resistance of this magnetic path. Conversely, the lower drive coil 10
The movable magnetic core 107 and the lower side 106c are provided in the magnetic path around the four.
Since the gap that is a space between and disappears, the magnetic resistance decreases. Therefore, even when the energization of the lower drive coil 104 is stopped, most of the magnetic flux of the permanent magnet 105 passes around the lower drive coil 104 having a small magnetic resistance, and the movable iron core portion 107 is attracted to the lower side portion 106c. Hold, and the open state is maintained.

[0011]

In the electromagnetic drive mechanism 101 for a switchgear having such a structure, the expensive upper drive coil 103 and the lower drive coil 104 are expensive because they perform both the opening operation and the closing operation. Two are required, and the use of these two drive coils raises the manufacturing cost and the volume.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned problems, and an object thereof is to provide an electromagnetic drive mechanism for a switchgear which is inexpensive and has a compact drive coil. And

[0013]

An electromagnetic drive mechanism for a switchgear according to the present invention is an electromagnetic drive mechanism for a switchgear which moves a movable contact back and forth to bring the movable contact to and from a fixed contact. A movable shaft connected to the contact, an annular drive coil provided so as to surround the movable shaft, and a first A yoke portion extending toward the movable shaft and having the drive coil interposed therebetween. And a first yoke having a first B yoke section, a first permanent magnet provided on the first yoke, and a first coil extending between the movable shaft and the drive coil. A second yoke having a 2A yoke part and a 2B yoke part, and a second yoke provided on the second yoke.
A permanent magnet, and a surface different from a surface on which a first magnetic path that links the drive coil is formed by the movable shaft, the first yoke, and the first permanent magnet, and the first magnetic path exists. The movable shaft, the second yoke, and the second yoke so that a second magnetic path having a magnetic flux in the direction opposite to the magnetic flux of the first magnetic path is formed in the movable shaft while interlinking with the drive coil. The second permanent magnet is disposed, the first magnetic path and the second magnetic path each have a gap, and the first magnetic path corresponds to contact and separation of the movable contact and the fixed contact. Alternatively, the gap of one of the magnetic paths of the second magnetic path is larger than the gap of the other magnetic path, and the drive coil is energized to cancel out the magnetic flux of the other magnetic path. Generates a magnetic flux that increases the magnetic flux in one magnetic path, It is adapted to move the.

The movable shaft comprises a movable shaft portion and a movable iron core portion having a large radial dimension of the movable shaft portion, and the first permanent magnet is provided at an end portion of the first A yoke portion. The first yoke has a first facing surface facing the one end surface of the movable iron core portion, and the second yoke is arranged to face a side surface of the movable iron core portion. The permanent magnet is provided at an end of the second A yoke portion and is arranged to face a side surface of the movable iron core portion.
The yoke has a second facing surface facing the other end surface of the movable iron core portion in the second B yoke portion, and is provided between the one end surface and the first facing surface or between the other end surface and the second facing surface. Either one of the facing surfaces forms a gap in the one magnetic path.

Further, the first permanent magnets constitute a first permanent magnet pair in which the same poles of the permanent magnets face each other via the movable shaft, and each of the first permanent magnets of the first permanent magnet pair comprises The second permanent magnet is provided in each of the first A yoke portions of the first yoke, and the second permanent magnets form a second permanent magnet pair in which the same poles of the permanent magnets face each other through the movable shaft, Each of the second permanent magnets of the two permanent magnet pairs is provided in each of the second A yoke portions of the second yoke.

The first yoke includes a first movable yoke portion having a first B yoke portion fixed to the movable shaft, and end faces of the first A yoke portion and the first movable yoke portion. A first fixed yoke portion having a first fixed facing surface opposed to, and the second yoke has a second movable yoke portion having a second B yoke portion fixed to the movable shaft, A second having a second fixed facing surface facing the end surfaces of the second A yoke section and the second movable yoke section
A fixed yoke portion, and the first movable yoke portion and the first fixed facing surface, or between the second movable yoke portion and the second fixed facing surface The gap of one magnetic path is formed.

Further, both the area of the end surface of the first movable yoke portion and the area of the first fixed facing surface and the area of the end surface of the second movable yoke portion and the area of the second fixed facing surface both become large. ing.

Further, the first permanent magnet is internal to the first fixed yoke portion, and the second permanent magnet is internal to the second fixed yoke portion.

A magnetic body is interposed between the drive coil and the first permanent magnet.

A magnetic body is interposed between the drive coil and the second permanent magnet.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. 1 is a perspective view showing the configuration of an electromagnetic drive mechanism for a switchgear according to Embodiment 1 of the present invention. In FIG. 1, an electromagnetic drive mechanism 1 for a switchgear moves a movable contact (not shown) back and forth to bring the movable contact into and out of contact with a fixed contact (not shown), and a movable contact connected to the movable contact. The shaft 2, the annular drive coil 3 provided so as to surround the movable shaft 2, the first A yoke portion 4 and the first A yoke portion 4 extending toward the movable shaft 2 and having the drive coil 3 interposed therebetween. A first yoke 6 having a 1B yoke portion 5, a first permanent magnet 7 provided on the first yoke 6, and a drive coil 3 that extends toward the movable shaft 2 and is interposed therebetween. No. 2A yoke section 8 and No. 2
A second yoke 10 having a B yoke section 9, and this second yoke 10
And a second permanent magnet 11 provided in the.

The movable shaft 2 has the same center axis as that of the movable shaft 12 and the movable shaft 12 connected to the movable contact.
2 and a movable core portion 13 having a larger dimension in the radial direction. The movable shaft portion 12 penetrates the movable iron core portion 13 and is fixed to the movable iron core portion 13, and moves together with the movable iron core portion 13 in the axial direction of the movable shaft 2.
The movable core portion 13 is a rectangular parallelepiped, and the movable shaft portion 12 penetrates and is fixed in the longitudinal direction thereof.

The drive coil 3 is provided so as to surround the middle portion of the movable iron core portion 13. The drive coil 3 is electrically connected to a power source (not shown), and generates a magnetic flux when energized by the power source.

The first yoke 6 is a magnetic material made of iron, for example. The first yoke 6 has one end surface 13 a of the movable iron core 13.
On the side, two first B yoke portions 5 extending toward the movable shaft portion 12 in a direction substantially perpendicular to the axis of the movable shaft 2 are joined together to be integrally formed, and the movable portion is movable at this joined portion. The shaft portion 12 is slidably mounted. The first B yoke portion 5 has a first facing surface 5a that faces the one end surface 13a of the movable iron core portion 13, so that the one end surface 13a of the movable iron core portion 13 and the first facing surface 5a contact and separate from each other. Has become. Also,
The first A yoke portion 4 is integrated with each of the two first B yoke portions 5 outside the drive coil 3 via the first side portion 14, and the drive coil 3 is provided. The movable iron core portion 13 is extended toward both side surfaces on the other end surface 13b side.

The first permanent magnets 7 are provided one at an end of each first A yoke portion 4, and the first permanent magnets 7 face the opposite side surfaces of the movable iron core portion 13 with a gap therebetween. It constitutes a pair of magnets. In addition, each of the first permanent magnets 7
Are provided so that the same pole (for example, N pole) faces the side surface of the movable iron core portion 13, respectively.

The second yoke 10 is a magnetic body made of iron, for example. The second yoke 10 has the other end surface 13 of the movable core portion 13.
Two second B yoke portions 9 extending toward the movable shaft portion 12 in the direction perpendicular to the axis of the movable shaft 2 on the b side are joined together to be integrally formed. The movable shaft portion 12 is slidably inserted at the connecting portion of the portion 9.
The second B yoke portion 9 has a second facing surface 9a that faces the other end surface 13b of the movable iron core portion 13, and
The other end surface 13b and the second facing surface 9a are brought into contact with and separated from each other. In addition, the second A yoke portion 8 is the two second B
Both of the yoke portions 9 are integrated with each other outside the drive coil 3 via the second side portion 17, and both end surfaces of the movable core portion 13 on the one end face 13a side from the location where the drive coil 3 is provided. Has been extended toward. In addition, the second B yoke section 9
The second and second A yoke portions 8 are substantially perpendicular to the first and second B yoke portions 5 and 4, respectively.

The second permanent magnets 11 are provided one at each end of each second A yoke portion 8, and the second permanent magnets 11 face the opposite side surfaces of the movable iron core portion 13 with a gap therebetween. It constitutes a pair of magnets. In addition, each of the second permanent magnets 1
1 is provided with the same pole (for example, N pole) facing the side surface of the movable iron core portion 13. In addition,
The second permanent magnet 11 faces a side surface different from the side surface of the movable core portion 13 to which the first permanent magnet 7 faces, and the pole facing the side surface is the same as that of the first permanent magnet 7.

FIG. 2 shows yz including the axis of the movable shaft 2 of FIG.
FIG. 3 is a cross-sectional view in the plane, and FIG. 3 is a cross-sectional view in the xz plane including the axis of the movable shaft 2 in FIG. Further, in the electromagnetic drive mechanism 1 for a switchgear shown in FIGS. 1 to 3, one end surface 13a of the movable core portion 13 is substantially in contact with the first facing surface 5a of the first yoke 6 and the movable contact and the fixed contact are in contact with each other. That is, it is in the closed state. In FIG. 2, the magnetic flux generated by the first permanent magnet 7 is directed in the direction of arrow 20 to the first permanent magnet 7 and the movable iron core portion 1.
3 and a first magnetic path 21 formed by the first yoke 6. In FIG. 3, the magnetic flux generated by the second permanent magnet 11 is the second magnetic path 2 formed by the second permanent magnet 11, the movable core portion 13 and the second yoke 10 in the direction of the arrow 22.
Go through 3. Therefore, the magnetic flux of the first permanent magnet 7 and the magnetic flux of the second permanent magnet 11 that pass through the inside of the movable iron core portion 13 are in opposite directions. 2 and 3, in the closed state, the movable iron core portion 13 has the one end face 13a of the first yoke 6
Substantially abutting on the first facing surface 5a of the
There is a certain amount of gap in the first magnetic path 21 because there is a gap with the permanent magnet 7, but there is a sufficiently large space between the other end surface 13b and the second facing surface 9a. This portion becomes a gap 24 which is sufficiently larger than the gap existing in the first magnetic path 21 and exists in the second magnetic path 23. Therefore, the gap 24 has a large magnetic resistance, and the second magnetic path 23 has the first magnetic path 2
There is less magnetic flux than the magnetic flux that passes through 1.
Therefore, the one end surface 13a on the first magnetic path 21 and the first facing surface 5a continue to be attracted to each other, and the closed state is maintained.

Next, the operation of the electromagnetic drive mechanism 1 for switchgear will be described with reference to FIGS. 2 and 3. 2 and 3
The opening operation for shifting from the closed state to the open state is performed as follows. First, the drive coil 3 is energized so that the magnetic flux is generated in the same direction as the magnetic flux generated by the second permanent magnet 11 indicated by the arrow 22 in the second magnetic path 23. By this energization, the direction of the arrow 22 in the second magnetic path 23, that is, the second magnetic path 23
The magnetic flux is generated in the same direction as the magnetic flux of the permanent magnet 11, and at the same time, the magnetic flux is generated in the direction of the arrow 20 in the first magnetic path 21, that is, in the direction opposite to the magnetic flux of the first permanent magnet 7. Due to the generation of magnetic flux by the drive coil 3 as described above,
In the second magnetic path 23, the magnetic flux generated by the drive coil 3 is added to the magnetic flux generated by the second permanent magnet 11 to generate the second magnetic path 23.
The magnetic flux passing through the first magnetic path 21 increases and the magnetic flux flowing through the first permanent magnet 7 and the magnetic flux flowing through the drive coil 3 are opposite to each other in the first magnetic path 21. To do.

When the magnetic flux passing through the second magnetic path 23 exceeds the magnetic flux passing through the first magnetic path 21, the movable iron core portion 13 moves to the second facing surface 9
The second end surface 13b contacts the second facing surface 9a. Along with this, the movable contact of the movable shaft portion 12 separates from the fixed contact and opens. Therefore, the space between the other end surface 13b and the second facing surface 9a becomes smaller, and conversely, the space between the one end surface 13a and the first facing surface 5a becomes larger, so that it exists in the second magnetic path 23. The gap 24 that has been formed decreases, and the gap of the first magnetic path 21 increases due to this space portion. Therefore, the magnetic flux passing through the second magnetic path 23 becomes larger than the magnetic flux passing through the first magnetic path 21, and the state where the other end surface 13b is in contact with the second facing surface 9a, that is, the open state is maintained.

The closing operation for transitioning from the open state to the closed state is performed according to the same principle as the opening operation. That is, first
The drive coil 3 is energized so that the magnetic flux is generated in the same direction as the magnetic flux of the first permanent magnet 7 indicated by the arrow 20 of the magnetic path 21. Due to this energization, magnetic flux is generated in the first magnetic path 21 in the direction of the arrow 20, that is, in the same direction as the magnetic flux of the first permanent magnet 7, and at the same time, in the second magnetic path 23, the direction of the arrow 22, that is, the second magnetic path 23. Magnetic flux is generated in the direction opposite to the direction of the magnetic flux by the permanent magnet 11. Due to the generation of the magnetic flux by the drive coil 3 as described above, the magnetic flux by the drive coil 3 is added to the magnetic flux by the first permanent magnet 7 in the first magnetic path 21, and the magnetic flux passing through the first magnetic path 21 increases. Second magnetic path 2
3, the directions of the magnetic flux generated by the second permanent magnet 11 and the magnetic flux generated by the drive coil 3 are opposite to each other, and thus cancel each other out.
The magnetic flux passing through the second magnetic path 23 decreases.

When the magnetic flux passing through the first magnetic path 21 exceeds the magnetic flux passing through the second magnetic path 23, the movable iron core portion 13 moves to the first facing surface 5
The one end surface 13a contacts the first facing surface 5a. Along with this, the movable contact of the movable shaft portion 12 is also moved and brought into contact with the fixed contact to close the contact. Therefore, the space between the one end surface 13a and the first facing surface 5a becomes small, and conversely, the space between the other end surface 13b and the second facing surface 9a becomes large, so that the space exists in the first magnetic path 21. The gap that has been formed is reduced, and the gap in the second magnetic path 23 is increased by this space portion, so that the gap 24 is generated in the second magnetic path 23. Therefore, the magnetic flux passing through the first magnetic path 21 is
Is greater than the magnetic flux passing through the first end surface 13a
The state of being in contact with a, that is, the closed state is maintained.

Therefore, the electromagnetic drive mechanism 1 for switchgear is
Both the opening operation and the closing operation can be performed by one drive coil 3, and the number of expensive drive coils is smaller than that in the conventional example, so that the size can be reduced and the cost can be reduced.

In the above embodiment, the first yoke 6 uses the first A yoke portion 4, the first B yoke portion 5, the first side portion 14 and the first permanent magnet 7 in pairs, The movable iron core portion 13 is provided on both sides of the movable iron core portion 13 by using the first A yoke portion 4, the first B yoke portion 5, the first side edge portion 14, and the first permanent magnet 7 one by one. Even if the structure is provided on only one side, the first magnetic path 21 is formed in the same manner.

Further, the second A yoke portion 8, the second B yoke portion 9, the second side edge portion 17 and the second permanent magnet 11 are used one by one, and are provided only on one side of the movable iron core portion 13. However, the second magnetic path 23 may be formed in the same manner.

The first yoke 6 and the second yoke 10 are a laminated body in which a plurality of iron plates are laminated in order to prevent eddy currents generated in the first yoke 6 and the second yoke 10. May be.

In the above embodiment, the first permanent magnet 7 is provided at the end of the first A yoke section 4, but the first permanent magnet 7 is provided at any location of the first yoke 6. Even the first
It does not matter because the permanent magnet 7 generates a magnetic flux passing through the first magnetic path 21.

The second permanent magnet 11 may be provided at any position of the second yoke 10 because the second permanent magnet 11 generates a magnetic flux passing through the second magnetic path 23.

Embodiment 2. Hereinafter, the same or equivalent members and parts as those of the first embodiment will be described with the same reference numerals.

FIG. 4 is a perspective view showing the structure of an electromagnetic drive mechanism for a switchgear according to Embodiment 2 of the present invention. Figure 4
In the first yoke 6, the first yoke 6 has a first movable yoke portion 30 fixed to the movable iron core portion 13 and a first fixed facing portion facing the first movable end surface 30 a which is an end surface of the first movable yoke portion 30. Surface 3
1a having a first fixed yoke portion 31 and a second yoke 1
0 is the second movable yoke section 32 fixed to the movable core section 13.
And a second fixed yoke section 33 having a second fixed facing surface 33a facing the second movable end surface 32a which is the end surface of the second movable yoke section 32.

The first movable yoke portion 30 is formed by integrating the first side portion 14 on the outer side of the drive coil 3 and the first A yoke portion 4, and the end of the first A yoke portion 4. Part is movable iron core part 1
The configuration is fixed to 3. In addition, the first movable yoke portion 30 is formed by extending two first A yoke portions 4 on opposite side surfaces of the movable iron core portion 13.
It is designed to move with. This first side part 1
4, the end surface on the first fixed yoke portion 31 side is the first movable end surface 30a.
Has become.

The first fixed yoke portion 31 is the first B yoke portion 5, and has a first fixed facing surface 31a facing the first movable end surface 30a on the side surface of the end portion. First fixed yoke section 31
Is one in which the two first B yoke portions 5 are joined together. The movable shaft portion 12 slidably penetrates through this connecting portion. Also, this first fixed yoke section 31
Have a first permanent magnet 7 therein and each of the first B
The yoke portion 5 has the same pole (for example, N
Poles) are provided one by one so as to face each other.

The second movable yoke portion 32 is formed by integrating the second side portion 17 on the outer side of the drive coil 3 and the second A yoke portion 8, and the end of the second A yoke portion 8. Part is movable iron core part 1
The configuration is fixed to 3. The second movable yoke portion 32 is formed by extending two second A yoke portions 8 on opposite side surfaces of the movable iron core portion 13.
It is designed to move with. This second side portion 1
The end surface of the No. 7 on the second fixed yoke portion 33 side is the second movable end surface 32a.
Has become.

The second fixed yoke portion 33 is the second B yoke portion 9 and has a second fixed facing surface 33a facing the second movable end surface 32a on the end side surface. Second fixed yoke 33
Indicates that the two second B yoke portions 9 are integrated with each other. The movable shaft portion 12 slidably penetrates through this connecting portion. In addition, the second fixed yoke section 33 has the second permanent magnet 11 therein, and the same pole (for example, N pole) faces the second B yoke section 9 around the axis of the movable shaft 2. They are provided one by one. The poles facing the second permanent magnets 11 are the same as the poles facing the first permanent magnets 7.

The other structure is similar to that of the first embodiment.

FIG. 5 shows xz including the axis of the movable shaft 2 of FIG.
FIG. 6 is a cross-sectional view in the plane, and FIG. 6 is a cross-sectional view in the yz plane including the axis of the movable shaft 2 in FIG. 4. Also, FIG.
In the electromagnetic drive mechanism 1 for switchgear shown in FIG. 6, the first movable end surface 30a of the first movable yoke portion 30 has the first fixed yoke portion 3
The movable contact and the fixed contact are in contact with the first fixed facing surface 31a of the first contact, that is, in the closed state. In FIG. 5, the magnetic flux generated by the first permanent magnet 7 is directed to the first permanent magnet 7, the first fixed yoke portion 31, and the first movable yoke portion 3 in the direction of arrow 35.
0, the movable core portion 13 and the movable shaft portion 12 pass through the first magnetic path 36. In FIG. 6, the magnetic flux generated by the second permanent magnet 11 is generated by the second permanent magnet 11, the second fixed yoke portion 33, the movable shaft portion 12, the movable iron core portion 13 and the second movable yoke portion 32 in the direction of arrow 37. It passes through the formed second magnetic path 38. Therefore, the magnetic flux of the first permanent magnet 7 passing through the inside of the movable iron core portion 13 and the second permanent magnet 11
It is opposite to the magnetic flux due to. In FIGS. 5 and 6, the first movable end surface 30a is substantially in contact with the first fixed facing surface 31a in the closed state, so that the second movable end surface 32a.
A large space portion exists between the second fixed facing surface 33a and the second fixed facing surface 33a, and this portion becomes a gap 39 larger than the gap of the first magnetic path 36 and exists in the second magnetic path 38. Therefore, the gap 39 has a large magnetic resistance, and the magnetic flux passing through the second magnetic path 38 is smaller than the magnetic flux passing through the first magnetic path 36. Therefore, the first movable end surface 30a and the first fixed facing surface 31a on the first magnetic path 36 continue to be attracted to each other, and the closed state is maintained.

Next, the operation of the electromagnetic drive mechanism 1 for the switchgear will be described with reference to FIGS. 5 and 6. 5 and 6
The opening operation of shifting from the closed state to the opened state is performed in the following manner based on the same principle as in the first embodiment. That is, first, the second permanent magnet 11 indicated by the arrow 37 of the second magnetic path 38 is shown.
The drive coil 3 is energized so that the magnetic flux is generated in the same direction as that of the magnetic flux. By this energization, a magnetic flux is generated in the second magnetic path 38 in the direction of the arrow 37, that is, in the same direction as the magnetic flux of the second permanent magnet 11, and at the same time, the first magnetic flux is generated.
A magnetic flux is generated in the magnetic path 36 in the direction of the arrow 35, that is, in the direction opposite to the direction of the magnetic flux of the first permanent magnet 7. Due to the generation of the magnetic flux by the drive coil 3 as described above, in the second magnetic path 38,
The magnetic flux generated by the drive coil 3 is added to the magnetic flux generated by the second permanent magnet 11, and the magnetic flux passing through the second magnetic path 38 increases. In the first magnetic path 36, the direction of the magnetic flux generated by the first permanent magnet 7 and the drive coil. Since the directions of the magnetic fluxes due to 3 are opposite, they cancel each other out, and the magnetic flux passing through the first magnetic path 36 decreases.

When the magnetic flux passing through the second magnetic path 38 exceeds the magnetic flux passing through the first magnetic path 36, the second movable yoke section 32 moves toward the second fixed facing surface 33a of the second fixed yoke section 33. Move
At the same time, the movable iron core portion 13, the movable shaft portion 12, the drive coil 3, and the first movable yoke portion 30 move toward the second fixed yoke portion 33. After that, the second movable end surface 32a substantially contacts the second fixed facing surface 33a, and the movable contact is separated from the fixed contact to open the contact. Therefore, the second movable end surface 32
Since a substantially contacts the second fixed facing surface 33a, the space between the second movable end surface 32a and the second fixed facing surface 33a becomes smaller, and conversely, the first movable end surface 30a and the first fixed facing surface 30a. Since the space between the first movable end surface 30a and the first fixed facing surface 31a is reduced in the first magnetic path 36, the space between the first movable end surface 30a and the first fixed facing surface 31a is reduced. The gap due to the space portion increases.
Therefore, the magnetic flux passing through the second magnetic path 38 becomes larger than the magnetic flux passing through the first magnetic path 36, and the state in which the second movable end surface 32a is in contact with the second fixed facing surface 33a, that is, the open state is maintained.

The closing operation is performed on the same principle as the opening operation. That is, first, the drive coil 3 is energized so that the magnetic flux is generated in the same direction as the magnetic flux of the first permanent magnet 7 indicated by the arrow 35 of the first magnetic path 36. Due to this energization, magnetic flux is generated in the first magnetic path 36 in the direction of arrow 35, that is, in the same direction as the magnetic flux of the first permanent magnet 7, and at the same time, in the second magnetic path 38 in the direction of arrow 37, that is, the second magnetic path. Magnetic flux is generated in the direction opposite to the direction of the magnetic flux by the permanent magnet 11. Due to the generation of the magnetic flux by the drive coil 3, the magnetic flux by the drive coil 3 is added to the magnetic flux by the first permanent magnet 7 in the first magnetic path 36, and the magnetic flux passing through the first magnetic path 36 increases. In the second magnetic path 38, the directions of the magnetic flux from the second permanent magnet 11 and the magnetic flux from the drive coil 3 are opposite to each other, so they cancel each other out, and the magnetic flux passing through the second magnetic path 38 decreases.

When the magnetic flux passing through the first magnetic path 36 exceeds the magnetic flux passing through the second magnetic path 38, the first movable yoke section 30 moves toward the first fixed facing surface 31a of the first fixed yoke section 31. Move
At the same time, the movable iron core portion 13, the movable shaft portion 12, the drive coil 3, and the second movable yoke portion 32 move toward the first fixed yoke portion 31. After that, the first movable end surface 30a comes into contact with the first fixed facing surface 31a, and the movable contact comes into contact with the fixed contact to close the contact. Therefore, when the first movable end surface 30a comes into contact with the first fixed facing surface 31a, the space between the first movable end surface 30a and the first fixed facing surface 31a becomes smaller, and conversely, the first movable end surface 32a becomes smaller. Since the space between the second fixed facing surface 33a and the second fixed facing surface 33a is increased, the gap existing in the first magnetic path 36 is reduced, and the second movable end surface 32a and the second fixed facing surface 33a are added to the second magnetic path 38. The gap 39 due to the space between and increases again. For this reason,
The magnetic flux passing through the first magnetic path 36 becomes larger than the magnetic flux passing through the second magnetic path 38, and the first movable end surface 30a becomes the first fixed facing surface 31a.
The state separated from, that is, the closed state is maintained.

Therefore, as in the first embodiment, the electromagnetic drive mechanism 1 for switchgear can perform both the opening operation and the closing operation by one drive coil 3, which is more expensive than the conventional example. Since the number of driving coils is small, it is possible to reduce the size and cost.

The first yoke 6 is the first fixed yoke portion 31.
And the first movable yoke portion 30 are used one by one, the first fixed magnet portion 31 is configured such that the first permanent magnet 7 is present therein, and is provided only on one side of the drive coil 3. However, since the first magnetic path 36 is formed, it does not matter.

Further, even if the first permanent magnet 7 is provided in the first movable yoke portion 30, it does not matter because it generates a magnetic flux passing through the first magnetic path.

The second yoke 10 has the second fixed yoke portion 3
3 and the first movable yoke portion 32 are used one by one,
Even if the second permanent magnet 11 is configured to be internally provided in the second fixed yoke portion 33 and provided on only one side of the drive coil 3, the second magnetic path 38 is formed, so that it does not matter.

Further, even if the second permanent magnet 11 is provided in the second movable yoke portion 32, it does not matter because it generates a magnetic flux passing through the second magnetic path.

The movable core portion 13 is eliminated if the movable shaft 2 is made of a magnetic material such as iron and has a sufficient cross-sectional area for forming the first magnetic path 36 and the second magnetic path 38. Good.

Further, with the reciprocal movement of the movable shaft 2, the first
Since the movable end surface 30a comes in contact with and separates from the first fixed facing surface 31a, the first side edge portion 14 may be integrated with the first B yoke portion 5 to form the first fixed yoke portion 31, or First side part 1
4 is divided into parts, one of which is integrated with the first A yoke section 4 to form the first movable yoke section 30, and the other of which is integrated with the 1B yoke section 5 to be the first fixed yoke section 31 may be configured.

FIG. 7 shows a first yoke with the first movable end surface and the first fixed facing surface having a large area, and a second yoke with the second movable end surface and the second fixed facing surface having a large area. 8 is a perspective view in which the electromagnetic drive mechanism for a switchgear is applied, but as shown in FIG. 7, a first movable end surface 30a and a first fixed facing surface 3 are provided.
By increasing the area of 1a and the areas of the second movable end surface 32a and the second fixed facing surface 33a, the first movable end surface 30 by the small first permanent magnet 7 and the second permanent magnet 11 is formed.
a and the attraction force of the first fixed facing surface 31a and the attraction force of the second movable end surface 32a and the second fixed facing surface 33a become large, so that the first permanent magnet 7 and the second permanent magnet 11 can efficiently perform the above. It is possible to generate a suction force and reliably maintain the closed state and the opened state.

Third Embodiment FIG. 8 is taken along the yz plane including the axis of the movable shaft 2 when the first magnetic body is interposed between the drive coil 3 and the first permanent magnet 7 of the electromagnetic drive mechanism 1 for a switchgear of FIG. 9 is a sectional view, and FIG. 9 includes the axis of the movable shaft 2 when the second magnetic body is interposed between the drive coil 3 and the second permanent magnet 11 of the electromagnetic drive mechanism 1 for a switchgear of FIG. It is sectional drawing along the xz plane.

In FIG. 8 and FIG. 9, the electromagnetic drive mechanism 1 for a switchgear includes a first magnetic body 40 which is a magnetic body such as iron interposed only between the drive coil 3 and the first permanent magnet 7, and a drive coil. 3 and the second magnetic body 41 which is a magnetic body such as iron interposed only between the second permanent magnet 11 and the third permanent magnet 11. Other configurations are similar to those of the first embodiment.

In FIG. 8, since the first magnetic body 40 is interposed between the first permanent magnet 7 and the drive coil 3, the magnetic flux generated by the first permanent magnet 7 is the first magnetic path 21 and the first correction. Two magnetic paths of the magnetic path 42 pass in the directions of arrows 43 and 44, respectively. Further, in FIG. 9, since the second magnetic body 41 is similarly interposed between the second permanent magnet 11 and the drive coil 3, the magnetic flux generated by the second permanent magnet 11 is the second magnetic path 23 and the second magnetic path 23. Two magnetic paths of the correction magnetic path 45 pass in the directions of arrows 46 and 47, respectively. Therefore, according to the same principle as in the first embodiment,
The closed state is maintained.

The opening operation is also performed according to the same principle as that of the first embodiment, but most of the magnetic flux generated by energizing the drive coil 3 passes through the first drive magnetic path 48 including the first magnetic body 40 in the arrow direction. Since the magnetic flux generated by the drive coil 3 passes through the second drive magnetic path 50 including the second magnetic body 41 in the direction indicated by the arrow 51, the magnetic flux generated by the drive coil 3 almost passes through the first permanent magnet 7 and the second permanent magnet 11. It does not pass, and the effect on the first permanent magnet 7 and the second permanent magnet 11 is small. Similarly, in the case of the closing operation, the influence on the first permanent magnet 7 and the second permanent magnet 11 is small.

Therefore, the magnetic flux in the direction opposite to the magnetic flux generated by the first permanent magnet 7 and the second permanent magnet 11 passes through the first permanent magnet 7 and the second permanent magnet 11 to be demagnetized, and
It is possible to prevent the long-term reliability of the permanent magnet 7 and the second permanent magnet 11 from not being ensured.

The first magnetic body 40 is interposed between the drive coil 3 and the first permanent magnet 7 of the switchgear electromagnetic drive mechanism 1 of the second embodiment, and the drive coil 3 and the second permanent magnet 11 are provided.
Even if the second magnetic body 41 is interposed between them, the same effect can be obtained.

[0065]

As is apparent from the above description, the electromagnetic drive mechanism for a switchgear according to the present invention is an electromagnetic drive mechanism for a switchgear that moves a movable contact back and forth to bring the movable contact to and from the fixed contact. A movable shaft connected to the movable contact, an annular drive coil provided so as to surround the movable shaft, and a first drive coil extending between the movable shaft and the movable coil. 1A Yoke and 1B
A first yoke having a yoke portion, a first permanent magnet provided on the first yoke, and a second A yoke extending toward the movable shaft and having the drive coil interposed therebetween. Portion and a second yoke portion having a second B yoke portion, and a second permanent magnet provided on the second yoke, the movable shaft, the first
A first magnetic path that links the drive coil is formed by the yoke and the first permanent magnet, and the movable shaft is linked to the drive coil on a surface different from the surface on which the first magnetic path exists. In the above, the movable shaft, the second yoke and the second permanent magnet are arranged so that a second magnetic path having a magnetic flux in a direction opposite to that of the magnetic flux in the first magnetic path is formed. The first magnetic path and the second magnetic path each have a gap, and correspond to contact and separation of the movable contact and the fixed contact,
The gap of one magnetic path of the first magnetic path or the second magnetic path is set to be larger than the gap of the other magnetic path, and the drive coil is electrically connected to the other magnetic path of the other magnetic path. Since the magnetic flux is generated so as to increase the magnetic flux of the one magnetic path while canceling the magnetic flux, and the movable shaft is moved, one movable coil reciprocates the movable shaft to perform the opening / closing operation. It can be made compact and can be manufactured at low cost.

The movable shaft includes a movable shaft portion and a movable iron core portion having a large radial dimension of the movable shaft portion.
The first permanent magnet is provided at an end of the first A yoke portion and is arranged to face a side surface of the movable iron core portion, and the first yoke is attached to the first iron yoke portion of the movable iron core. A second facing magnet is provided at an end of the second A yoke portion, and is arranged to face a side surface of the movable iron core portion. Two
The yoke has a second facing surface facing the other end surface of the movable iron core portion in the second B yoke portion, and is provided between the one end surface and the first facing surface or between the other end surface and the second facing surface. Since the gap of the one magnetic path is formed on either one of the facing surfaces, the movable iron core portion is locked to the first B yoke portion or the second B yoke portion to determine the movement range. be able to.

The first permanent magnets form a first permanent magnet pair in which the same poles of the permanent magnets face each other via the movable shaft, and each of the first permanent magnets of the first permanent magnet pair is The second permanent magnet is provided in each of the first A yoke portions of the first yoke, and the second permanent magnets form a second permanent magnet pair in which the same poles of the permanent magnets face each other through the movable shaft, Since each of the second permanent magnets of the two permanent magnet pairs is provided in each of the second A yoke portions of the second yoke, the magnetic flux generated by the drive coil can be efficiently used, and the movable iron core portion has both sides. Since the force is received evenly from the above, it is possible to smoothly reciprocate without tilting.

The first yoke is a first movable yoke portion having a first B yoke portion fixed to the movable shaft, and end faces of the first A yoke portion and the first movable yoke portion. A first fixed yoke portion having a first fixed facing surface opposed to, and the second yoke has a second movable yoke portion having a second B yoke portion fixed to the movable shaft, A second having a second fixed facing surface facing the end surfaces of the second A yoke section and the second movable yoke section
A fixed yoke portion, and the first movable yoke portion and the first fixed facing surface, or between the second movable yoke portion and the second fixed facing surface Since the gap of one magnetic path is formed, the first movable yoke portion and the second movable yoke portion are locked to the first fixed yoke portion and the second fixed yoke portion, respectively. Thus, the moving range of the movable shaft can be determined.

Further, the areas of the end surface of the first movable yoke portion and the first fixed facing surface and the areas of the end surface of the second movable yoke portion and the second fixed facing surface both become large. Therefore, the reliability of holding the open contact state and the closed contact state is increased.

Since the first permanent magnet is internal to the first fixed yoke portion and the second permanent magnet is internal to the second fixed yoke portion, the first magnetic path and the first permanent magnet portion are the same. The two magnetic paths are easily formed, and the impact due to the movement of the movable shaft is smaller than that in the case where the first permanent magnet and the second permanent magnet are provided on the movable shaft. The reliability of the second permanent magnet against damage is increased.

Further, since the magnetic body is interposed between the drive coil and the first permanent magnet, demagnetization of the first permanent magnet can be prevented and long-term reliability of the first permanent magnet can be secured.

Further, since the magnetic body is interposed between the drive coil and the second permanent magnet, demagnetization of the second permanent magnet can be prevented and long-term reliability of the second permanent magnet can be secured.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration of an electromagnetic drive mechanism for a switchgear according to Embodiment 1 of the present invention.

2 is a cross-sectional view in the yz plane including the axis of the movable shaft in FIG.

3 is a cross-sectional view in the xz plane including the axis of the movable shaft in FIG.

FIG. 4 is a perspective view showing the configuration of an electromagnetic drive mechanism for a switchgear according to Embodiment 2 of the present invention.

5 is a cross-sectional view in the xz plane including the axis of the movable shaft in FIG.

6 is a cross-sectional view in the yz plane including the axis of the movable shaft in FIG.

FIG. 7 is a schematic diagram showing a first yoke having a large area of a first movable end surface and a first fixed facing surface and a second yoke having a large area of a second movable end surface and a second fixed facing surface. It is a perspective view applied to a drive mechanism.

8 is a cross-sectional view taken along the yz plane including the axis of the movable shaft, when the first magnetic body is interposed between the drive coil and the first permanent magnet of the electromagnetic drive mechanism for the switchgear of FIG. .

9 is a cross-sectional view taken along the xz plane including the axis of the movable shaft when the second magnetic body is interposed between the drive coil and the second permanent magnet of the electromagnetic drive mechanism for the switchgear of FIG. .

FIG. 10 is a cross-sectional view showing a configuration of a conventional electromagnetic drive mechanism for a switchgear.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Electromagnetic drive mechanism for switchgear, 2 movable shaft, 3 drive coil, 4 1A yoke section, 5 1B yoke section, 5a 1st facing surface, 6 1st yoke, 7 1st permanent magnet, 8th Two
A yoke portion, 9 2B yoke portion, 9a 2nd facing surface, 10
2nd yoke, 11 2nd permanent magnet, 12 movable shaft part, 1
3 movable core part, 13a one end face, 13b other end face, 2
1,36 First magnetic path, 23,38 Second magnetic path, 24,3
9 Gap, 30 1st movable yoke part, 30a 1st movable end surface, 31 1st fixed yoke part, 31a 1st fixed opposing surface, 32 2nd movable yoke part, 32a 2nd movable end surface, 3
3 2nd fixed yoke part, 33a 2nd fixed opposing surface, 40 1st magnetic body (magnetic body), 41 2nd magnetic body (magnetic body).

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinji Sato             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. (72) Inventor Toshie Takeuchi             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. (72) Inventor Kenichi Koyama             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. (72) Inventor Takafumi Nakagawa             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. (72) Inventor Shunji Yamamoto             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. F-term (reference) 5G028 AA08 DB08

Claims (8)

[Claims] 1. An electromagnetic drive mechanism for a switchgear that reciprocates a movable contact to bring the movable contact into and out of contact with a fixed contact, wherein the movable shaft is connected to the movable contact and surrounds the movable shaft. An annular drive coil provided; a first yoke having a first A yoke portion and a first B yoke portion extending toward the movable shaft and having the drive coil interposed therebetween; A first permanent magnet provided on the first yoke, and a second yoke having a second A yoke portion and a second B yoke portion extending toward the movable shaft and having the drive coil interposed therebetween. And a second permanent magnet provided on the second yoke, wherein the movable shaft, the first yoke and the first permanent magnet form a first magnetic path interlinking with the drive coil. , The drive coil on a surface different from the surface on which the first magnetic path exists The movable shaft, the second yoke and the second permanent magnet are arranged so that a second magnetic path having a magnetic flux in the direction opposite to the direction of the magnetic flux of the first magnetic path is formed in the movable shaft. The first magnetic path and the second magnetic path each have a gap, corresponding to contact and separation of the movable contact and the fixed contact,
The gap of one of the first magnetic path and the second magnetic path is larger than the gap of the other magnetic path, and the drive coil is connected to the other magnetic path by being energized. An electromagnetic drive mechanism for a switchgear, which is configured to generate a magnetic flux that increases the magnetic flux of the one magnetic path while canceling the magnetic flux to move the movable shaft. 2. The movable shaft includes a movable shaft portion and a movable iron core portion having a large radial dimension of the movable shaft portion, and the first permanent magnet is provided at an end portion of the first A yoke portion. The first yoke is provided and is arranged to face a side surface of the movable core portion, and the first yoke has a first facing surface facing the one end surface of the movable iron core portion in the first B yoke portion, 2 permanent magnets are provided at the ends of the second A yoke portion and are arranged to face the side surface of the movable iron core portion, and the second yoke is provided in the second iron yoke portion of the movable iron core portion. It has a second facing surface facing the other end surface, and a gap of the one magnetic path is provided between the one end surface and the first facing surface or between the other end surface and the second facing surface. The electromagnetic drive mechanism for a switchgear according to claim 1, wherein the electromagnetic drive mechanism is formed. 3. The first permanent magnets constitute a first permanent magnet pair in which the same poles of the first permanent magnets face each other via the movable shaft, and each of the first permanent magnet pairs of the first permanent magnets. A permanent magnet is provided in each of the first A yoke portions of the first yoke, and the second permanent magnets form a second permanent magnet pair in which the same poles of the permanent magnets face each other via the movable shaft. The switchgear according to claim 1 or 2, wherein each of the second permanent magnets of the second permanent magnet pair is provided in each of the second A yoke portions of the second yoke. Electromagnetic drive mechanism. 4. A first movable yoke portion having a first B yoke portion fixed to the movable shaft, and the first yoke.
A yoke portion and a first fixed yoke portion having a first fixed facing surface facing the end surface of the first movable yoke portion, wherein the second yoke is a second B fixed to the movable shaft. A second movable yoke portion having a yoke portion, and a second fixed yoke portion having a second fixed facing surface facing the end surfaces of the second movable yoke portion and the second movable yoke portion. And forming a gap of the one magnetic path either between the first movable yoke portion and the first fixed facing surface or between the second movable yoke portion and the second fixed facing surface. The electromagnetic drive mechanism for a switchgear according to claim 1, wherein: 5. The end surface of the first movable yoke portion and the first
The electromagnetic drive for a switchgear according to claim 4, wherein each area of the fixed facing surface and each area of the end surface of the second movable yoke portion and the second fixed facing surface are enlarged. mechanism. 6. The method according to claim 4, wherein the first permanent magnet is included in the first fixed yoke portion, and the second permanent magnet is included in the second fixed yoke portion. Item 6. An electromagnetic drive mechanism for a switchgear according to Item 5. 7. The electromagnetic drive mechanism for a switchgear according to claim 1, wherein a magnetic body is interposed between the drive coil and the first permanent magnet. 8. The electromagnetic drive mechanism for a switchgear according to claim 1, wherein a magnetic body is interposed between the drive coil and the second permanent magnet.