JPH0529133A - Electromagnet - Google Patents

Abstract

PURPOSE:To improve sensitivity of an electromagnet and reduce sizes and weight by improving the operation characteristic of the electromagnet using the repulsive characteristic of the electromagnet and using the superimposed effects of magnetic flux generated by a permanent magnet and the magnetic flux when electricity is conducted to a coil. CONSTITUTION:An electromagnet is composed of a stator 10, which is provided with a cylindrical yoke 1, a fixed iron core 2, a coil 3 and a guide pipe 7, and a needle 11, which is provided with magnetic pole pieces 5 and 6 firmly fixed on the both magnetic pole planes of a permanent magnet 4. When current is conducted to the coil 3, magnetic flux generated at the magnetic pole piece 5 is permitted to be in the same phase as the magnetic flux of the permanent magnet 4 generated at the magnetic pole piece 5 and the fixed iron core 2 and the magnetic pole piece 5 are permitted to be repulsing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a solenoid valve, a solenoid relay,
The present invention relates to an electromagnet used for an electromagnetic operation mechanism or the like.

[0002]

2. Description of the Related Art As is well known, a conventional electromagnet is a spring in which a coil wound around a fixed iron core is energized to cause a movable iron core arranged with a magnetic pole surface of the fixed iron core and an operating gap to act on the movable iron core. It has a configuration and a function of suction-holding against, and releasing this holding state by stopping the energization of the coil and releasing it by the spring force to restore the operation gap. That is, the magnetic attraction force between the fixed iron core and the movable iron core is utilized by energization.

[0003]

However, the above-mentioned prior art has the following problems. (1) The magnetic attraction and repulsive force of the electromagnet sharply decrease exponentially as the distance between the magnetic pole faces (operating interval length) increases. That is, in the conventional electromagnet utilizing the magnetic attraction force, the maximum operation gap is obtained at the start of the attraction operation of the electromagnet, and the minimum operation gap length is obtained at the end of the attraction operation. Therefore, the conventional electromagnet has a drawback in that the required electric input is increased at the start of the suction operation, and the maximum attraction force is generated at the end of the operation.

(2) In the conventional electromagnet, when the energization of the coil is stopped, the force for releasing the close contact between the magnetic pole surfaces of the fixed iron core and the movable iron core depends on the mechanical energy stored in the spring during the attraction operation, so that the attraction operation The electric input at time is increased by the mechanical energy of the spring. (3) In conventional electromagnets that are operated by a DC power supply, depending on the material of the iron core used, there is a risk that the operation reliability when the movable iron core is opened may be impaired due to the effect of residual magnetic flux. There are many things to do.

An object of the present invention is to solve the above problems and to provide an electromagnet which produces a repulsive force with high sensitivity, small size, light weight and low cost.

[0006]

The present invention adopts the following technical means in order to solve the above problems. That is, (a) a cylindrical yoke having one end closed with a bottom plate and the other end opened, a fixed iron core projecting from the bottom plate coaxially with the yoke in the yoke, a coil wound around the fixed iron core, and the vicinity of the opening of the yoke. A stator consisting of a non-magnetic guide pipe fixed to the inner surface, and a yoke arranged coaxially with the yoke facing the end surface of the fixed core on the opening side in the yoke, magnetized in the axial direction, and magnetic pole pieces on both magnetic pole surfaces respectively. The electromagnet is provided with a mover made of a permanent magnet in the form of a cylinder or a hollow cylinder to which is fixed, and uses the repulsive force between the stator and the mover.

(B) The two stators of (a) are coaxially connected so that their opening end faces coincide with each other, and are magnetized in the axial direction and have first and second magnetic pole pieces on both magnetic pole faces. A mover consisting of a fixed columnar or hollow cylindrical permanent magnet is arranged between both fixed iron cores so that they can alternately come in contact with and separate from both fixed iron cores, and a current of a predetermined polarity is simultaneously applied to each coil. When energized, a repulsive force is generated between one of the fixed iron cores and the first magnetic pole piece that is attracted, and an attractive force is generated between the other fixed iron core and the second magnetic pole piece that are separated, or one of the separated ones is separated. An attractive force may be generated between the fixed iron core and the first magnetic pole piece, and a repulsive force may be generated between the other fixed iron core and the second magnetic pole piece that are attracted.

(C) A cylindrical yoke having one end closed with a bottom plate having a concentric circular hole and the other end opened, and a stator composed of a cylindrical coil coaxially arranged on the inner wall of the yoke on the circular hole side, and the yoke. A cylindrical permanent magnet disposed on the opening side of the permanent magnet and magnetized in the axial direction, a first magnetic pole piece fixed to the magnetic pole surface of the permanent magnet on the opening side of the yoke, and one surface fixed to another magnetic pole surface of the permanent magnet. The contact surface of the coil contacts the coil end surface, and the repulsive force between the stator and the mover is also caused by the mover including the second magnetic pole piece having the plunger fixed to the center of the coil and inserted into the coil and the circular hole. Can be used.

(D) The two stators shown in (c) are coaxially arranged so that their opening end faces are aligned with each other, and the mover shown in (c) is replaced with both magnetic pole faces of the permanent magnet shown in (c). When a new mover in which the second magnetic pole piece of (c) is symmetrically fixed is inserted and a current of a predetermined polarity is simultaneously applied to each coil, a repulsive force is exerted between one coil attracted and the first magnetic pole piece. To generate an attractive force between the other coil and the second magnetic pole piece that are separated from each other,
Alternatively, an attractive force may be generated between one of the separated coils and the first magnetic pole piece, and a repulsive force may be generated between the other attracted coil and the second magnetic pole piece.

(E) When the coil is energized and the mover is separated from the stator at the opening end face of the cylindrical yoke, the mover is stopped to bring the mover to a stable position, and the energization of the coil is stopped. Also, a ring-shaped magnetic pole piece that latches the mover with the magnetic flux of the permanent magnet should be provided so that when the polarity of the current flowing through the coil is changed, the mover is displaced from the ring-shaped magnetic pole piece to the stator side and operates bistablely. You can also

(F) A cylindrical yoke whose both end surfaces are closed by a bottom plate having concentric bearing holes, a ring-shaped magnetic pole piece provided inwardly on the inner surface of the yoke at a central portion in the axial direction of the yoke, and a yoke between the magnetic pole piece and both bottom plates. A stator composed of a pair of coils coaxially arranged on the inner wall side, and a plunger inserted into both bearing holes,
An axially magnetized permanent magnet fixed to the plunger surrounding the plunger and a mover made of a cylindrical magnetic body surrounding the permanent magnet and fixed to the permanent magnet are provided. When a polar current is applied, a repulsive force may be generated between one of the bottom plates to be attracted and the mover, and a suction force may be generated between the other bottom plate and the mover to be separated.

(G) It is preferable that the abutting surfaces of the solid iron core or the stator and the mover have an irregular truncated cone shape in which they are fitted to each other. (H) A predetermined spring reaction force may be applied between the solid iron core or the stator and the mover. (I) The magnetic pole surface of the permanent magnet and the magnetic pole piece may be fixed to each other via an elastic body so as to be capable of slight oscillation.

(J) Notches may be provided at predetermined intervals in the axial direction on the circumferential surface of the cylindrical yoke.

[0014]

First, the operation of the first embodiment of the present invention will be described with reference to FIG. In this embodiment, a yoke 1 is provided with a fixed iron core 2 projecting therefrom, a coil 3 is wound around the fixed iron core 2, and a magnetic pole piece 5 is provided on each of the magnetic pole surfaces of a permanent magnet 4 magnetized in the axial direction.
And a mover to which the pole piece 6 is fixed. The side surfaces of the magnetic pole pieces 5 and 6 face the inner surface of the yoke 1 with a slight gap. FIG. 2A shows the case where the coil 3 is not energized, only the magnetic flux by the permanent magnet 4 indicated by the solid arrow is present, and the shunt magnetic flux φma to the fixed iron core 2 is the magnetic pole piece 5.
Since the magnetic flux is larger than the shunt magnetic flux φmb (the magnetic resistance is large on the φmb side due to the small gap for sliding with the non-magnetic guide pipe), the magnetic pole piece 5 of the mover is attracted to the fixed iron core 2 and is stabilized. ing. In this state, when the coil is energized to induce a magnetic flux in the pole piece 5 as shown by a dotted arrow in the figure, the fixed iron core 2 and the movable element 2 are moved by the action of the permanent magnet 4 overlapping the magnetic flux shown by a solid arrow. A repulsive force is generated between them, and the movable element moves to the position of the mover shown in FIG. 2B and holds it (the holding function of the mover is not limited in this example). When the energization of the coil 3 is stopped here, due to the action of the magnetic flux of φma in the figure, the weight of the mover, or the spring force of another embodiment of the present invention not shown,
It can function as an electromagnet having a magnetic repulsion action for returning the mover to the position shown in FIG.

That is, the electromagnet of the present embodiment is a monostable operation in which the operation of the mover is controlled depending on whether or not the coil is energized, and the maximum force is generated at the beginning of the repulsion operation of the mover, and the magnetic energy of the permanent magnet is applied. It is possible to exhibit high sensitivity characteristics that are effectively used. It can also be configured for bistable operation, as found in other embodiments of the invention.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an explanatory view of the first embodiment of the present invention. FIG. 1A is a diagram showing a partial vertical section, and FIG. 1B is a view taken along the line AA of FIG. 1A. In the present embodiment, as described above in part, the stator 10, which includes the yoke 1, the fixed iron core 2, the coil 3, and the guide pipe 7, and the magnetic pole pieces 5 on both magnetic pole surfaces of the permanent magnet 4 magnetized in the axial direction, Movable element 11 to which 6 is fixed
In the state of FIG. 1A, the coil 3 is energized, the magnetic flux of the electromagnet and the magnetic flux of the permanent magnet 4 act on the pole piece 5 in the same phase, and a repulsive force is generated between the stator 10 and the mover 11. Is configured to occur.

FIG. 3 shows a specific example of the first embodiment of the present invention, FIG. 3 (a) is a partial longitudinal sectional view, FIG. 3 (b) is a component of the stator 10, and FIG. (C) is an exploded view of the constituent parts of the mover 11. Further, another embodiment of the embodiment shown in FIG. 1 is shown in FIG.
When a ring-shaped magnetic pole piece 9 is provided on the opening end face of the coil 3 and the coil 3 is energized to separate the mover 11 from the stator, the mover 11 is stopped to bring the mover 11 to a stable position, and Even when the energization of the coil 3 is stopped, the mover 11 is latched by the magnetic flux of the permanent magnet 4, and when the polarity of the energizing current of the coil 3 is changed, the mover 11 is attracted to the stator to perform a bistable operation. It can also be configured.

The operation of the embodiment shown in FIG. 4 will be described with reference to FIG. As shown in FIG. 5B, when the energization of the coil is stopped and the magnetic flux φ _ma <the magnetic flux φ _mb , the mover is attracted and held by the magnetic pole piece 9. Next, when the coil is energized as shown in FIG. 5B, the condition of φ _i + φ _ma > φ _mc is satisfied, and the mover returns to the position shown in FIG. 5A.

Next, a second embodiment of the present invention will be described.
FIG. 6 is an explanatory view of the second embodiment of the present invention and is a view showing a partial vertical cross section. FIG. 6 shows the stator 10 of the electromagnet of FIG.
1 is coaxially connected to each other at the opening end faces thereof, and the mover 11 is disposed between the fixed iron cores 2. For simplification, a mechanism for transmitting the movement of the mover 11 to the outside is omitted in FIG. Reference numeral 12 is a fixing metal member for fixing the stators 10 to each other.

FIG. 7 is an explanatory view of the operation of the embodiment shown in FIG. The magnetic flux generated by the permanent magnet 4 shown by the solid arrow in the figure and the magnetic flux φ _i2 when the coil 3 shown by the dotted arrow is pulse-energized are superposed in the same phase in the first magnetic pole piece 5 and in the opposite phase in the second magnetic pole piece 6. Thus, a repulsive force is simultaneously applied between the mover and the left-side fixed iron core 2, and a suction force is simultaneously applied between the mover and the right-side fixed iron core 2, so that the mover is attracted to the right-side fixed iron core 2 side. Is to have. Further, by energizing each coil 3 with the opposite polarity, the mover is returned to the position shown in the figure, and it can be operated as a so-called pulse-driven, bistable high-sensitivity electromagnet.

FIG. 8 shows a third embodiment of the present invention. 8A is an explanatory view including a partial cross section, FIG. 8B is a view taken along the line ABCD of FIG. 8A, and FIG.
It is an EF-G-H arrow line view of (a). In the embodiment shown in FIG. 8, the fixed iron core 2 of FIG. 1 is not provided, and the mover 11 is composed of a permanent magnet 4, a first magnetic pole piece 5 and a second magnetic pole piece 6 having a plunger. Ring-shaped magnetic pole piece 9 shown in FIG.
If there is not, monostable operation is performed, and if the ring-shaped magnetic pole piece 9 is provided, bistable operation is performed.

In the embodiment shown in FIG. 8, the distance (gap) between the stator and the mover 11 is constant due to the action of the plunger even if the mover 11 moves, and the magnetic resistance of the magnetic path is small. It is suitable for an electromagnet having a large required stroke length as compared with the configuration of FIG. 9A and 9B are explanatory views of the operation of the third embodiment. FIG. 9A is a state in which the mover and the stator are attracted, and FIG. 9B is a state in which they are separated. Is shown. Since the operation of FIG. 9 is the same as that of FIG. 2, the description thereof will be omitted.

FIG. 10 shows a fourth embodiment of the present invention.
That is, in FIG. 10A, the stator shown in FIG. 8 is coaxially continuously arranged so that the opening end faces of the cylindrical yoke 1 coincide with each other to form a stator. The two magnetic pole pieces 6 are provided as movable elements for bistable operation. FIG. 11 is a diagram for explaining the operation.
11A and 11B show stable positions and magnetic flux distributions.

FIG. 12 shows the fifth embodiment of the present invention.
A cylindrical yoke 1a whose both end surfaces are closed by bottom plates 1b and 1c having concentric bearing holes, a ring-shaped magnetic pole piece 9a provided on the inner surface of the yoke at the center of the yoke in the axial direction, and a yoke between the magnetic pole pieces and both bottom plates. A pair of coils 3 arranged coaxially on the inner wall side
And a plunger 13 inserted into both bearing holes, an axially magnetized permanent magnet 4 fixed to the plunger 13 surrounding the plunger 13, and a permanent magnet 4.
Is provided with a mover made of a cylindrical magnetic body 14 that is fixedly attached so as to be bistable. The feature of this embodiment is that the suction holding force in each stable state can be increased.

FIG. 13 is a diagram for explaining the operation of FIG. 12, and FIG.
3 (a) and FIG. 13 (b) show each stable position and each magnetic flux distribution. FIG. 14 shows an embodiment of the electromagnet of the present invention in which the abutting portions of the fixed iron core 2 and the mover 11 are formed in the shape of a truncated cone that fits with each other. Therefore, the spring for returning is not necessary, and the sensitivity of the electromagnet can be increased and the operation reliability can be improved. As another example of this embodiment, the configuration may be as shown in FIG.

FIG. 15 shows an embodiment in which the notches 15 are provided at predetermined intervals in the axial direction on the circumferential surface of the cylindrical yoke 1a. When the cylindrical yoke 1a has such a shape, it can be pressed. It can be manufactured and is cheaper than drawing.
FIG. 4 is also an explanatory view of another embodiment of the present invention. That is, the permanent magnet 4 of the mover 11 and the first and second magnetic pole pieces 5 and 6 are fixed to each other via the elastic body 8 so as to be able to slightly swing. By providing the elastic body 8, the mover 1
It is possible to absorb and stabilize variations in electromagnet performance caused by variations in the processing accuracy of the components that make up 1,
Further, it is possible to reduce impact force and impact sound when the stator and the mover 11 are attracted.

Although not shown, a predetermined spring reaction force can be applied between the stator and the mover. For example, when applied to the electromagnet of FIG. 1, the monostable operation can be made a bistable operation. When applied to a bistable electromagnet as shown in FIG. 6, a bias force of a spring can be applied between the attractive force and the repulsive force, and the required attractive force characteristics can be obtained.

In the present embodiment, the yokes 1 and 1a have a cylindrical shape, but the yoke does not necessarily have to have a circular cross section, and may have a partially cut shape as described above.
The permanent magnet, the non-magnetic guide pipe, and the magnetic pole piece also do not need to stick to the cross-sectional shape orthogonal to the axis, and the non-magnetic guide pipe may be fixed to the mover side.

[0029]

The present invention has the following excellent effects. (A) Electromagnetic repulsion force Generally, a mechanical system motion requires a large acting force at the start of the motion, and it is desirable to make the acting force constant or gradually decrease with the progress of the motion. The present invention eliminates the disadvantage that the conventional attraction type electromagnet generates a small acting force at the start of exercise and an excessive acting force at the end of exercise due to the interposition of the operating gap, and maximizes the force at the beginning of exercise. By utilizing the electromagnetic repulsive force that generates the acting force, the operating characteristics of the electromagnet can be greatly improved.

(B) Energy Utilization of Permanent Magnet By superimposing the energy of the permanent magnet on the energy of the electromagnet generated by energizing the coil, a highly sensitive operation is possible. (C) Various operating characteristics energization type (depending on whether or not the coil is energized), pulse actuating type (operation depending on the polarity of pulse energization to the coil), or
It is possible to manufacture a monostable, bistable or multi-stable electromagnet, such as a pulse stepping type (stepping operation depending on the number of times of pulsed current to the coil).

Moreover, it is possible to mass-produce an electromagnet having a small size, a light weight, a simple and sturdy structure.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a first embodiment of the present invention.
1A is a diagram showing a partial vertical cross section, and FIG. 1B is FIG. 1A.
FIG.

FIG. 2 is an explanatory view of the operation of the first embodiment of the present invention, FIG. 2 (a) is a monostable position of the mover when the coil is not energized, and FIG. 2 (b) is a coil energized. The state of the mover at the time is shown (the holding mechanism of the mover is not shown).

FIG. 3 shows a first embodiment of the present invention, FIG. 3 (a) is a partial longitudinal cross-sectional view, FIG. 3 (b) is a component of a stator, and FIG. 3 (c) is a mover. The components are shown.

4 is another embodiment of the embodiment shown in FIG.
4A is a diagram showing a partial vertical section, and FIG. 4B is FIG. 4A.
It is a BB arrow line view of. FIG. 4A also shows an embodiment in which the magnetic pole surface of the permanent magnet and the magnetic pole piece are fixed to each other via an elastic body so that they can be slightly rocked.

5A and 5B are explanatory views of the operation of FIG. 4, in which FIG. 5A shows one stable position of the mover, and FIG. 5B shows another stable position of the mover.

FIG. 6 is an explanatory view of the second embodiment of the present invention, and is a view showing a partial vertical section.

FIG. 7 is an explanatory view of the operation of FIG.

FIG. 8 is an explanatory diagram of the third embodiment of the present invention.
8A is a diagram showing a partial vertical section, and FIG. 8B is FIG. 8A.
8C is a view taken along the arrow ABCD, and FIG. 8C is a view taken along the arrow EFGH of FIG. 8A.

9A and 9B are diagrams for explaining the operation of FIG. 8, in which FIG. 9A shows a state where the stator and the mover are adsorbed, and FIG. 9B shows a state where the stator and the mover are separated from each other. .

10 is an explanatory diagram of the fourth embodiment of the present invention, and FIG.
0 (a) is a diagram showing a partial vertical section, and FIG.
FIG. 10A is a view taken along arrow A-B-C-D of FIG.
It is an EF-G-H arrow line view of 0 (a).

11A and 11B are explanatory views of the operation of FIG. 10, where FIG. 11A shows one stable position of the stator and the mover, and FIG. 11B shows another stable position of the stator and the mover.

12 is an explanatory diagram of the fifth embodiment of the present invention, and FIG.
2 (a) is a view showing a partial vertical cross section, and FIG. 12 (b) is FIG.
It is an A-B-C-D arrow line view of (a).

13A and 13B are explanatory views of the operation of FIG. 12, FIG. 13A shows one stable position of the stator and the mover, and FIG. 13B shows another stable position of the stator and the mover.

FIG. 14 is an explanatory view of an embodiment of the contact surface between the stator and the mover of the present invention, FIG.
Indicates the time of separation.

15A and 15B are explanatory views of an embodiment of a cylindrical yoke of the present invention, FIG. 15A is an external view, and FIG. 15B is FIG.
It is an A-B-C-D arrow line view of (a).

[Explanation of symbols]

1, 1a Yoke 1b, 1c Bottom plate 2 Fixed iron core 3 Coil 4 Permanent magnet 5 First magnetic pole piece 6 Second magnetic pole piece 7 Guide pipe 8 Elastic body 9, 9a Ring-shaped magnetic pole piece 10 Stator 11 Mover 12 Fixing metal fitting 13 Plunger 14 Cylindrical magnetic body 15 Notches φ _i , φ _i2 , φ _ma , φ _mb , φ _mc ... Magnetic flux

Claims (10)

[Claims] 1. A cylindrical yoke having one end closed by a bottom plate and the other end opened, a fixed iron core projecting from the bottom plate coaxially with the yoke in the yoke, a coil wound around the fixed iron core, and the yoke. A stator composed of a non-magnetic guide pipe fixed to the inner surface near the opening and a stator coaxially arranged on the opening side of the yoke so as to face the fixed core end surface and magnetized in the axial direction. An electromagnet comprising a mover made of a columnar or hollow cylindrical permanent magnet having pole pieces fixed to respective pole faces, and using repulsive force between the stator and the mover. 2. A columnar structure in which the two stators are coaxially connected with their opening end faces aligned and are axially magnetized, and first and second magnetic pole pieces are fixed to both magnetic pole faces, respectively. A mover made of a hollow cylindrical permanent magnet is arranged between the fixed iron cores so as to be alternately contactable with and separated from the fixed iron cores coaxially with the fixed iron cores, and a current of a predetermined polarity is simultaneously applied to the coils. One of the fixed iron core and the first
The repulsive force between the magnetic pole pieces of the
Attracting force between each of the magnetic pole pieces, or repelling the attracting force between one of the fixed iron cores and the first magnetic pole piece that are separated from each other, and between the other fixed iron core that attracts the magnetic pole piece and the second magnetic pole piece. The electromagnet according to claim 1, which generates forces respectively. 3. A stator comprising a cylindrical yoke having one end closed by a bottom plate having a concentric circular hole and the other end opened, and a cylindrical coil coaxially arranged on the inner wall of the yoke on the side of the circular hole. A cylindrical permanent magnet disposed on the opening side of the yoke and magnetized in the axial direction; a first magnetic pole piece fixed to a magnetic pole surface of the permanent magnet on the opening side of the yoke; The fixed element is provided with a mover made of a second magnetic pole piece fixed to the magnetic pole surface, the other surface of which is in contact with the coil end surface, and a plunger fixed to the center of the coil and inserted into the circular hole. An electromagnet characterized by using a repulsive force between a child and the mover. 4. The two stators are arranged coaxially so that their opening end faces are aligned with each other, and the second magnetic pole pieces are symmetrically fixed to both magnetic pole faces of the permanent magnet instead of the mover. When a new movable element is inserted and a current of a predetermined polarity is simultaneously applied to each coil, a repulsive force is generated between one coil attracted and the first magnetic pole piece and the other coil is separated from the second magnetic pole piece. Attracting force between each of the magnetic pole pieces, or an attracting force between one of the separated coils and the first magnetic pole piece, and a repulsive force between the other attracted coil and the second magnetic pole piece. The electromagnet according to claim 3, which is generated respectively. 5. The coil is energized to the opening end surface of the cylindrical yoke, and when the mover is separated from the stator, the mover is stopped to bring the mover to a stable position and the coil is Is provided with a ring-shaped magnetic pole piece that latches the mover with the magnetic flux of the permanent magnet when the energization of the coil is stopped, and when the polarity of the current flowing through the coil is changed, the mover moves from the ring-shaped magnetic pole piece to the stator. The electromagnet according to claim 1 or 3, which is displaced to the side and operates bistablely. 6. A cylindrical yoke whose both end surfaces are closed by a bottom plate having concentric bearing holes, a ring-shaped magnetic pole piece provided internally to the inside surface of the yoke at a central portion in the axial direction of the yoke, the magnetic pole piece and the both bottom plates. A stator composed of a pair of coils coaxially arranged on the inner wall side of the yoke between, a plunger inserted into the bearing holes, and an axial direction fixed to the plunger surrounding the plunger. A permanent magnet magnetized with a magnet, and a mover made of a cylindrical magnetic body that surrounds the permanent magnet and is fixed to the permanent magnet. One of the magnets is attracted when a current of a predetermined polarity is simultaneously applied to each coil. Repulsive force between the bottom plate and the mover,
An electromagnet, which generates an attractive force between the movable plate and the other bottom plate that is separated from each other. 7. The electromagnet according to claim 1, wherein the contact surfaces of the solid iron core or the stator and the mover are in the shape of a truncated cone with which they are fitted to each other. 8. The electromagnet according to claim 1, wherein a predetermined spring reaction force is applied between the mover and the solid iron core or the stator. 9. The magnetic pole surface of the permanent magnet and the magnetic pole piece are
7. The device according to claim 1, wherein the device is fixed via an elastic body so that it can be slightly rocked.
The electromagnet according to any one of items. 10. The electromagnet according to claim 1, wherein notches are provided at predetermined intervals in the axial direction on the circumferential surface of the cylindrical yoke.