JP2014220311A - Electromagnet device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnet device in which one pole face of a permanent magnet can be arranged to face a movable iron core and can also prevent the breakage of a holder made of a nonmagnetic material covering a magnetic piece and the permanent magnet.SOLUTION: An electromagnet device has: a fixed iron core 7 formed by laminating a plurality of magnetic plates; a movable iron core 8 which is formed by laminating a plurality of magnetic plates and moves forward and backward in the fixed iron core; an electromagnetic coil 10 arranged in the fixed iron core; and a drive shaft arranged at the center of the movable iron core. The electromagnet device further comprises: a permanent magnet 11 which is arranged on a surface of the fixed iron core facing the movable iron core, and whose one pole faces the movable iron core while the other pole comes into contact with the fixed iron core; a magnetic piece 101 arranged at the pole of the permanent magnet facing the movable iron core; and a holder 102 which is fastened to the fixed iron core so as to cover the magnetic piece and the permanent magnet, and which is made of a nonmagnetic material having an opening on a surface facing the magnetic piece and a shaft portion of the electromagnetic coil of the permanent magnet.

Description

  The present invention relates to an electromagnet device used for an operating mechanism of a switching device such as a circuit breaker.

  In an electromagnet device used in a conventional switchgear, a permanent magnet is disposed in a space provided in a fixed iron core and a fixed frame, both poles of the permanent magnet are opposed to the fixed iron core, and movement of surfaces other than the pole is performed by a fixed frame. It is fixed. Since the fixed frame is fixed with a fixed iron core and bolts, the fixed frame does not move. Therefore, the permanent magnet, the fixed frame, and the fixed iron core do not move relatively. (For example, see Patent Document 1)

Japanese Patent No. 5030923

  The electromagnet device used in the conventional switchgear described above can be employed only in a structure in which a permanent magnet can be disposed in the magnetic path of the fixed iron core. There is a problem that it cannot be adopted when one magnetic pole face is opposed to the movable iron core when the magnetic attraction force of the permanent magnet is generated.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to allow one magnetic pole face of a permanent magnet to face a movable iron core and to cover a magnetic piece and a permanent magnet. An object of the present invention is to obtain an electromagnet device capable of preventing breakage of a holder made of a magnetic material.

  An electromagnet device according to the present invention includes a fixed iron core configured by laminating a plurality of magnetic plates, a movable iron core configured by laminating a plurality of magnetic plates, and moving forward and backward in the fixed iron core, In an electromagnet apparatus having an electromagnetic coil provided on a fixed iron core and a drive shaft arranged at a central portion of the movable iron core, the pole is arranged on a surface facing the movable iron core of the fixed iron core, and one pole is movable. A permanent magnet opposite to the iron core and the other in contact with the fixed iron core, a magnetic piece disposed on a pole opposite to the movable iron core of the permanent magnet, the magnetic piece and the permanent magnet covering the fixed magnet A surface that is fixed to an iron core and that faces the shaft portion of the electromagnetic coil of the magnetic piece and the permanent magnet is provided with a holder made of a non-magnetic material that is opened.

  According to the electromagnet device according to the present invention, an electromagnet device is obtained in which one magnetic pole surface of the permanent magnet can be opposed to the movable iron core and the breakage of the holder made of the nonmagnetic material covering the magnetic piece and the permanent magnet can be prevented. be able to.

It is sectional drawing which shows the electromagnet apparatus concerning Embodiment 1 of this invention. It is sectional drawing which shows the electromagnet apparatus concerning Embodiment 1 of this invention. It is sectional drawing in the AA of FIG. 2 which shows the electromagnet apparatus concerning Embodiment 1 of this invention. It is sectional drawing which shows the magnetic flux in the electromagnet apparatus concerning Embodiment 1 of this invention.

Embodiment 1 FIG.
Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS. 1 to 4. In the drawings, the same or corresponding members and parts are denoted by the same reference numerals. 1 is a sectional view showing an electromagnet device according to Embodiment 1 of the present invention. FIG. 2 is a sectional view showing the electromagnet device according to Embodiment 1 of the present invention. 3 is a cross-sectional view taken along the line AA of FIG. 2, showing the electromagnet device according to Embodiment 1 of the present invention. FIG. 4 is a cross-sectional view showing the magnetic flux in the electromagnet device according to Embodiment 1 of the present invention.

  In each of these drawings, a vacuum valve 3 which is a switchgear body having a fixed contact 1 and a movable contact 2, an electromagnet device 4 for displacing the movable contact 2 of the vacuum valve 3 in a direction toward and away from the fixed contact 1, and a vacuum valve 3 and the electromagnet device 4, and the opening / closing device is constituted by the opening spring 6 that is an urging member that urges the movable contact 2 in a direction away from the fixed contact 1.

  The vacuum valve 3 serving as the switchgear body includes a fixed contact 1 and a movable contact 2 housed in an insulating container 3a, and one end of a movable electrode bar 3b fixed to the movable contact 2 is led out from the insulating container 3a to be connected. It is connected to the movable side of the electromagnet device 4 via the device 5. As a result, the movable contact 2 moves in the axial direction of the vacuum valve 3 and is displaced. When the movable contact 2 is in contact with the fixed contact 1, the contact is closed, and when the movable contact 2 is separated, the contact is opened. The inside of the vacuum valve 3 is kept in a vacuum in order to improve the arc extinguishing ability between the fixed contact 1 and the movable contact 2. A fixed electrode rod 3 c is fixed to the fixed contact 1.

  The electromagnet device 4 includes a fixed iron core 7 configured by laminating a plurality of magnetic plates, and a movable iron core 8 configured by laminating a plurality of magnetic plates and moving forward and backward in the fixed iron core 7. A drive shaft 9 penetrating through the central portion of the movable iron core 8 and fixed to the movable iron core 8, an electromagnetic coil 10 provided on the fixed iron core 7 to generate a magnetic field when energized, and provided on the fixed iron core 7 side. The permanent magnet 11, the support 12 for fixing the fixed iron core 7, and the opening side plate 13 and the closing side plate 14 disposed at both ends of the support 12. The movable core 8 is driven and displaced in the axial direction of the drive shaft 9 (hereinafter simply referred to as the axial direction) P with respect to the fixed core 7.

  Further, bearings 15a and 15b of the drive shaft 9 are fixed to portions where the drive shaft 9 penetrates the opening side plate 13 and the closing side plate 14, respectively.

  An opening spring receiver 16 is fixed to the other side 9 b of the drive shaft 9 protruding outward from the opening side plate 13, and the drive shaft between the opening side plate 13 and the opening spring receiver 16 is fixed. An opening spring 6 that is an urging member is inserted into the shaft portion 9. The opening spring 6 is, for example, a compressed coil spring, and generates an elastic repulsion force in the axial direction P between the opening side plate 13 and the opening spring receiver 16.

  Next, the configuration of the electromagnet device 4 will be described in more detail. Each of the fixed iron core 7 and the movable iron core 8 is formed by laminating a plurality of thin magnetic plates. The shape of the fixed iron core 7 is a horizontal iron core portion 7a extending in a direction orthogonal to the axial direction, a vertical iron core portion 7b extending in the axial direction from both ends of the horizontal iron core portion 7a, and extending from the vertical iron core portion 7b toward the axis. And a permanent magnet fixing portion 7c. The vertical iron core portion 7b of the fixed iron core 7 is clamped and fixed to the column 12 by being sandwiched by the columns 12 from both sides of the plate surface, that is, from both sides in the stacking direction.

  On the other hand, the movable iron core 8 has a backbone portion 8a arranged along the axial direction, and a pair of branch portions 8b protruding in opposite directions from the side surface of the backbone portion 8a in a direction orthogonal to the axial direction. ing. The fixed iron core 7 and the movable iron core 8 are integrated by being fastened by a plurality of bolts 18 passed in the stacking direction and nuts (not shown) screwed to the bolts 18. And it can displace between the retreat position which left | separated from the fixed iron core 7, and contacted the opening side plate 13, and the advance position contact | abutted to the fixed iron core 7. FIG.

  The material of the fixed iron core 7 and the movable iron core 8 may be a magnetic material having a high magnetic permeability, and examples thereof include steel, electromagnetic soft iron, silicon steel, ferrite, and permalloy.

  Further, as the material of the drive shaft 9, a material having a low magnetic permeability (low magnetic material) such as stainless steel is used.

  The permanent magnet 11 is disposed on the permanent magnet fixing portion 7 c of the fixed iron core 7 so as to face the surface on the closing side of the branching portion 8 b of the movable iron core 8. The permanent magnet 11 has an N pole and an S pole (a pair of magnetic poles), one of the magnetic poles is opposed to the permanent magnet fixing portion 7 c, and the other magnetic pole is the branch portion 8 b of the movable iron core 8. It faces the closed side.

  The permanent magnet 11 generates a holding magnetic flux for holding the movable iron core 8 in the forward movement position. For example, when the magnetic flux emitted from one pole of the permanent magnet 11 enters the other pole of the permanent magnet 11 via the movable iron core 8 and the fixed iron core 7, the force for attracting and holding the movable iron core 8 and the fixed iron core 7 is obtained. Is generated. The fixing of the permanent magnet 11 will be described later with reference to FIGS.

  Further, the electromagnetic coil 10 is disposed so as to pass between the trunk portion 8 a of the movable iron core 8 and the vertical iron core portion 7 b of the fixed iron core 7. In the example of this embodiment, the electromagnetic coil 10 surrounds the trunk portion 8a of the movable iron core 8 in the projection plane in the axial direction. Thereby, when the electromagnetic coil 10 is energized, it generates a magnetic flux passing through the fixed iron core 7 and the movable iron core 8. Further, the direction of the magnetic flux generated by the electromagnetic coil 10 can be reversed by switching the energization direction to the electromagnetic coil 10.

  Next, the connection part of the electromagnet apparatus 4 and the vacuum valve 3 which is a switchgear main body is demonstrated. The electromagnet device 4 is supported on a plate-like support member 19 via an attachment column 20. Usually, the vacuum valve 3 is accommodated in a container (not shown) in which an insulating gas (for example, SF6 gas, dry air, etc.) for securing the dielectric strength of the peripheral portion is sealed. For this reason, the support member 19 is, for example, a lid of the container, and the mounting column 20 is erected on the support member 19 made of this lid, and the closing side plate 14 of the electromagnet device 4 is mounted on the mounting column 20. Is fixed by bolting or the like. However, the support member 19 is not limited to this, and may be a switchboard support plate, for example.

  The connecting device 5 for connecting the movable electrode rod 3b fixed to the movable contact 2 of the vacuum valve 3 and the one side 9a of the drive shaft 9 of the electromagnet device 4 includes an insulating rod 21 connected to the movable electrode rod 3b, The pressure contact device 22 interposed between the insulating rod 21 and the one side 9a of the drive shaft 9 and the connecting rod 23 portion of the insulating rod 21 are part of the gas container at a portion passing through the support member 19. It has a bellows 24 provided by connecting the connecting rod 23 portion and the support member 19 so that the connecting rod 23 portion can move in an airtight manner with respect to the support member 19. The bellows 24 may be unnecessary depending on the configuration of the support member 19.

  The contact pressure device 22 includes a spring frame 25 fixed to an end portion of the connecting rod 23, a locking plate 26 fixed to one side 9 a of the drive shaft 9 and disposed in the spring frame 25, and the spring frame 25. And a contact-pressure spring 27 inserted in a compressed state. The contact pressure spring 27 urges the drive shaft 9 in a direction away from the insulating rod 21. The drive shaft 9 can be displaced in the axial direction together with the locking plate 26, and the displacement is regulated by the engagement of the locking plate 26 with the spring frame 25.

  In FIG. 1, the axis of the electromagnet device 4 and the axis of the vacuum valve 3 are shown in a straight line, but a configuration in which the direction is changed by interposing a lever or the like in the connecting device 5 may be used. .

  Next, the operation of the switchgear will be described. When the movable contact 2 is in an open state away from the fixed contact 1, the movable iron core 8 is in the retracted position by the biasing force of the opening spring 6. When the electromagnetic coil 10 is energized, the movable iron core 8 is attracted to the fixed iron core 7 and is displaced from the retracted position toward the advanced position against the load of the opening spring 6. As a result, the movable contact 2 moves toward the fixed contact 1.

  Thereafter, when the movable contact 2 comes into contact with the fixed contact 1, the movement of the movable contact 2 stops. However, the movable iron core 8 is further displaced, and the trunk portion 8a comes into contact with the horizontal iron core portion 7a of the fixed iron core 7 to reach the forward movement position. As a result, the contact pressure spring 27 is contracted, and the movable contact 2 is pressed against the fixed contact 1 with a predetermined pressing force to complete the closing operation.

  When the movable iron core 8 reaches the forward movement position, the movable iron core 8 is attracted and held by the holding magnetic flux of the permanent magnet 11 to hold the forward movement position.

  When the holding of the forward position of the movable iron core 8 is released, the electromagnetic coil 10 is energized in the direction opposite to that during the closing operation. As a result, the attractive force between the movable iron core 8 and the fixed iron core 7 decreases, and the movable iron core 8 moves to the retracted position by the loads of the opening spring 6 and the contact pressure spring 27. In the initial stage of displacement, the movable contact 2 remains pressed against the fixed contact 1.

  Thereafter, when the displacement toward the retracted position of the movable iron core 8 proceeds, the detachment prevention plate 26 is engaged with the spring frame 25. Thereby, the movable contact 2 is displaced in a direction away from the fixed contact 1. When the movable iron core 8 is further displaced and comes into close contact with the opening side plate 13 and reaches the retracted position (the state shown in FIG. 1), the opening operation is completed.

  Next, fixing of the permanent magnet 11 part of the electromagnet device in the switchgear according to Embodiment 1 of the present invention will be described with reference to FIGS. With respect to the movement in the horizontal direction with respect to the paper surface of FIG. 2, the movement of the permanent magnet 11 is restricted by the protrusions 7 c 1 and 7 c 2 provided on the permanent magnet fixing portion 7 c of the fixed iron core 7 of the electromagnet device 4 via the fixed frame 103. And fixed.

  In addition, the magnetic piece 101 disposed on the surface of the one pole facing the movable iron core 8 of the permanent magnet 11 is fixed to the fixed frame 103. It is clear that the movement in the downward direction with respect to the paper surface of FIG. 2 is restricted by the permanent magnet fixing portion 7 c of the fixed iron core 7. The upper direction with respect to the paper surface of FIG.

  The attachment of the holder 102 will be described with reference to FIG. 3 is a cross-sectional view taken along the line AA in FIG. 2, and the holder 102 moves upward from the paper surface of FIG. 3 of the permanent magnet 11 (the surface of one pole facing the movable iron core 8 also includes the magnetic piece 101). ) And is bent to both ends of the laminated layer of the fixed iron core 7, faces the plates at both ends of the fixed iron core 7, and is fixed together with the fixed iron core 7 by bolts 30 and nuts 31. The holder 102 is open in the direction toward the shaft portion of the electromagnetic coil 10, and the permanent magnet 11 and the magnetic piece 101 are not in contact with the surface facing the shaft portion of the electromagnetic coil 10.

  The material of the holder 102 is a nonmagnetic material. When the holder 102 is made of a magnetic material, for example, the magnetic flux emitted from one pole facing the movable core 8 of the permanent magnet 11 is in contact with the fixed core 7 of the permanent magnet 11 via the holder 102 and the fixed core 7. Will enter the pole. This is because the magnetic flux of the permanent magnet 11 that does not pass through the movable iron core 8 increases when the holder 102 is a magnetic body, and the force that attracts and holds the movable iron core 8 and the fixed iron core 7 decreases. Therefore, since the nonmagnetic holder 102 is disposed between the permanent magnet 11 and the movable iron core 8, the holder 102 is made of a material that is as thin as possible in order to reduce the nonmagnetic area of the permanent magnet 11 and the movable iron core 8. It is desirable to do.

  The magnetic piece 101 is made of a magnetic material such as a steel plate, and is disposed between the movable iron core 8 and one of the poles of the permanent magnet 11 facing the movable iron core 8, and at the forward position, the movable iron core 8 and the permanent magnet. The attractive force of the electromagnet device 4 is adjusted by adjusting the gap between the magnetic material pieces 101 with the magnetic piece 101. This is because, if the non-magnetic region is small between the movable iron core 8 and the permanent magnet 11, the suction holding force generated between the movable iron core 8 and the fixed iron core 7 is increased.

  A force acts on the magnetic piece 101 when the electromagnetic coil 10 of the electromagnet device 4 is energized. The concept of magnetic flux distribution when the electromagnetic coil 10 of the electromagnet device 4 is energized is shown in FIG. The closer to the shaft portion of the electromagnetic coil 10, the higher the density of magnetic flux lines, and the farther the density is, the lower the density of magnetic flux lines. Due to the magnetic flux distribution, the magnetic piece 101 is subjected to a force that tends to move toward a higher magnetic flux line density. A force acts in a direction toward the shaft portion of the electromagnetic coil 10. Since there is a fixed frame 103 in this moving direction, the magnetic piece 101 can be held without moving.

  With the above configuration, the holder 102 that needs to be manufactured as thin as possible is not fixed with respect to the movement of the magnetic piece 101 in the direction toward the shaft portion of the electromagnetic coil 10. The load does not work. It can be fixed with a fixed frame 103.

  For example, the holder 102 cannot be fixed because the holder 102 is thin. Further, when a part of the holder 102 is in contact with the surface of the magnetic piece 101 facing the shaft portion of the electromagnetic coil 10, the magnetic piece 101 is moved in the axial direction of the electromagnetic coil 10 every time the electromagnet device 4 is operated. A repetitive load such as a slight movement of the magnetic body 101 and a return to the original position by the fixed frame 103 after the operation is completed is in contact with the surface of the magnetic body piece 101 of the holder 102 facing the shaft portion of the electromagnetic coil 10. Since it acts on the part where it is, it will break due to metal fatigue. However, in the embodiment of the invention, since the holder 102 is not in contact with the portion, there is an effect that no breakage occurs.

  Further, as shown in FIG. 4, the movable iron core 8 is T-shaped, and the core portion 8 a of the movable iron core 8 enters the shaft portion of the electromagnetic coil 10, whereby the magnetic flux G of the magnetic piece 101 is distributed. Because the difference in distribution that the density closer to the shaft portion of the magnetic coil 10 is higher and the density farther from the shaft portion of the electromagnetic coil 10 is lower becomes larger, the movable iron core 8 of the embodiment of the present invention is used in the embodiment of the present invention. It is clear that is effective.

  Further, as shown in FIG. 3, the stacking direction of the fixed iron core 7 is perpendicular to the plane including the drive shaft 9, and the direction of the bolt 30 that penetrates and fixes the stack is relative to the plane including the drive shaft 9. If the holder 102 is in a vertical direction, the holder 102 is simply bent, and the holder 102 does not need to be in contact with the surface of the permanent magnet 11 / magnetic piece 101 facing the shaft portion of the electromagnetic coil 10. The holder 102 having the structure can fix the movement of the magnetic piece 101 and the permanent magnet 11 in the upward direction on the paper surface.

  In the present invention, the embodiments can be appropriately modified and omitted within the scope of the invention.

  The present invention is suitable for realizing an electromagnet apparatus in which one magnetic pole surface of a permanent magnet can be opposed to a movable iron core and the breakage of a holder made of a nonmagnetic material covering a magnetic piece and a permanent magnet can be prevented.

DESCRIPTION OF SYMBOLS 4 Electromagnet apparatus, 7 Fixed iron core, 8 Movable iron core, 8a Core part, 8b Branch part, 9 Drive shaft, 10 Electromagnetic coil, 11 Permanent magnet, 12 Support | pillar, 13 Opening side plate, 14 Closing side plate, 101 Magnetic body Piece, 102 holder, 103 fixed frame.

Claims (5)

  A fixed iron core configured by laminating a plurality of magnetic plates, a movable iron core configured by laminating a plurality of magnetic plates, and moving in and out of the fixed iron core, and an electromagnetic coil provided in the fixed iron core And an electromagnet device having a drive shaft disposed at a central portion of the movable core, wherein the fixed core is disposed on a surface facing the movable core, one pole facing the movable core and the other facing the movable core. A permanent magnet in contact with a fixed iron core; a magnetic piece disposed on a pole opposite to the movable iron core of the permanent magnet; and the magnetic piece covering the magnetic piece and the permanent magnet and fixed to the fixed iron core; An electromagnet device comprising a piece and a holder made of a non-magnetic material having a surface facing the shaft portion of the electromagnetic coil of the permanent magnet.   2. The electromagnet device according to claim 1, wherein the holder is fixed to the fixed iron core by a fixing member that penetrates between the laminated layers of the fixed iron cores and fixes the fixed iron core.   3. The electromagnet device according to claim 1, wherein a fixed frame surrounding the surface of the permanent magnet that is not a pole and the periphery of the magnetic piece is disposed.   The movable iron core is configured in a T-shape having a backbone portion arranged along the axial direction and a pair of branch portions protruding in opposite directions from the side surfaces of the backbone portion in a direction orthogonal to the axial direction. The electromagnet device according to any one of claims 1 to 3, wherein the electromagnet device is provided.   A support column that is provided in parallel to the axial direction of the drive shaft on both sides of the fixed iron core and supports the fixed iron core, and is provided at one end of the movable iron core in the longitudinal direction of the support column, and the drive shaft is supported through. 5. The open side plate, and a closed side plate, which is provided at the other end in the longitudinal direction of the support column and through which the drive shaft is supported. 5. The electromagnet device according to any one of the above.