JP2021136453A - Electromagnet and magnetic field application system - Google Patents

Abstract

To provide an electromagnet and a magnetic field application system, capable of applying a magnetic field in an arbitrary direction (biaxial detection) on an XZ plane in parallel with an X axis direction and a Z-axis direction.SOLUTION: An electromagnet 201 includes: a first yoke 130 including a pair of rod-like first magnetic pole ends that have magnetic poles 133a at their tips apart from each other along an X-axis direction so as to interpose a gap Gp therebetween and are disposed at positions axially-symmetrical to each other around a center axis CL in parallel with a Z-axis direction; a first coil 131 wound around the first yoke 130; a second yoke 140 that is magnetically connected to the first yoke 130 and has a rod-like portion coaxial with the center axis CL; and a second coil 141 wound around the second yoke 140. No magnetic pole pair of a yoke other than the first yoke 130 and the second yoke 140 is disposed in a first area Ar1, a circular area having a radius R1 and taking the center axis CL as its center. The radius R1 is longer than an inter-magnetic pole distance L1 in a radial direction of the center axis CL of the first magnetic pole ends 133.SELECTED DRAWING: Figure 9

Description

The present disclosure relates to an electromagnet and a magnetic field application system.

Processing equipment using electromagnets such as magnetic resistance measuring equipment, vibration sample magnetic field meter, electromagnets for various magnetic property measuring equipment such as MRAM / evaluation equipment, heat treatment equipment in magnetic field, magnetizing demagnetization processing equipment, saturated magnetic strain measuring equipment, etc. From the magnetic application industry to the semiconductor industry, as well as the medical and biotechnology fields, technologies that use magnetic fields have been put to practical use in many fields.

In the above fields, a magnetic field is applied in a desired direction to measure the characteristics of the object to be measured in a magnetic field, or the object to be processed is placed in a desired magnetic field and heat-treated to perform heat treatment or the like. In order to change the magnetic characteristics, a magnetic field is also applied in a desired direction by controlling a current or rotating the electromagnet using an electromagnet.

For example, Patent Document 1 discloses an electromagnet in which a magnetic field application region is set to only one side in the vertical direction (Z-axis direction) of the device, and restrictions on mechanical operation and an increase in size of the device are avoided. The electromagnet described in Patent Document 1 can apply a magnetic field in an arbitrary direction including the Z-axis direction which is the vertical direction and the X-axis direction and the Y-axis direction in the horizontal plane orthogonal to the Z-axis direction.

Japanese Patent No. 6473546

An electromagnet capable of applying a magnetic field in an arbitrary direction on an XZ plane parallel to the X-axis direction and the Z-axis direction is required instead of the three-axis directions of the X-axis direction, the Y-axis direction, and the Z-axis direction.

The present disclosure provides an electromagnet and a magnetic field application system capable of applying a magnetic field in an arbitrary direction on an XZ plane parallel to the X-axis direction and the Z-axis direction.

The electromagnet of the present disclosure has a pair of rod-shaped portions and a pair of first magnetic pole end portions provided at the tips of the pair of rod-shaped portions. A first yoke that is separated along the X-axis direction and is arranged at a position that is axially symmetric with each other about a central axis parallel to the Z-axis direction and can form a closed magnetic path together with the gap, and the first yoke. A first coil wound around the first yoke, a second yoke magnetically connected to the first yoke and having a rod-shaped portion coaxial with the central axis, and a second coil wound around the second yoke are provided. The magnetic pole pairs of the yokes other than the first yoke and the second yoke are not arranged in the first region which is a circular region having a radius R1 about the central axis, and the radius R1 is the diameter of the central axis. It is larger than the distance L1 between the magnetic poles of the first magnetic pole end in the direction.

The schematic plan view which shows the electromagnet and the magnetic field application system which concerns on 1st Embodiment. FIG. 1 is a cross-sectional view taken along the line AA of FIG. 1, and is an explanatory view relating to the generation of a magnetic field in the X direction. The side view which shows the electromagnet of 1st Embodiment. FIG. 1 is a cross-sectional view taken along the line AA of FIG. 1, and is an explanatory view relating to the generation of a magnetic field in the Z direction. Explanatory drawing about a problem which arises in a conventional electromagnet. The schematic plan view which shows the electromagnet and the magnetic field application system which concerns on 2nd Embodiment. FIG. 6 is a cross-sectional view taken along the line BB of FIG. 6, which is an explanatory view relating to the generation of a magnetic field in the X direction. The side view which shows the electromagnet of the 2nd Embodiment. The schematic plan view which shows the electromagnet and the magnetic field application system which concerns on 3rd Embodiment. FIG. 5 is a cross-sectional view showing an electromagnet of the fourth embodiment. (A) A first example of the fourth embodiment is shown. (B) A second example of the fourth embodiment is shown. The schematic plan view which shows the electromagnet and the magnetic field application system of the 3rd example of 4th Embodiment. FIG. 11 is a sectional view taken along line CC and a sectional view taken along line DD.

[First Embodiment]
Hereinafter, the first embodiment of the present disclosure will be described with reference to FIGS. 1 to 4.

<Magnetic field application system>
FIG. 1 is a schematic plan view showing an electromagnet 1 constituting a magnetic field application system. The magnetic field application system is configured so that a magnetic field in an arbitrary direction on the XZ plane parallel to the X-axis direction and the Z-axis direction can be applied to the object to be applied. The arbitrary direction does not include the Y-axis direction. As shown in FIG. 1, the magnetic field application system includes an electromagnet 1 and a current supply unit 2 that supplies a current to the electromagnet 1. The X-axis direction, the Y-axis direction, and the Z-axis direction are directions orthogonal to each other, and are used for facilitating the description of the invention. Since the orientation of the electromagnet 1 differs depending on the method of use, the orientation is not limited to the orientation shown in the drawings of the present disclosure.

<Electromagnet>
As shown in FIGS. 1 and 2, the electromagnet 1 includes an X-axis electromagnet 3 for generating a magnetic field of an X-axis direction component, a Z-axis electromagnet 4 for generating a magnetic field of a Z-axis direction component, and the like. Has.

The X-axis electromagnet 3 has a first yoke 30, a first coil 31 and a third coil 32 wound around the first yoke 30.

The first yoke 30 is made of a soft ferromagnet, has a pair of first magnetic pole end portions 33 in which the magnetic pole 33a at the tip is separated along the X-axis direction with the gap Gp in between, and is magnetically closed together with the gap Gp. The path mp_X can be formed. As shown in FIG. 1, the pair of first magnetic pole end portions 33 are arranged at positions symmetrical with each other about the central axis CL parallel to the Z-axis direction. As a result, a magnetic flux parallel to the XY plane can be generated on the central axis CL. In the present embodiment, the first yoke 30 is C-shaped in side view, but is not limited thereto. The first magnetic pole end portion 33 is provided at the tip of the rod-shaped portion 34. The rod-shaped portion 34 has a shape extending in a straight line, but is not limited to this as long as it has a long shape. For example, a shape that extends while bending or a shape that extends in a curved shape may be used. In the present embodiment, as shown in FIG. 2, the first yoke 30 has a rod-shaped portion 34 including the first magnetic pole end portion 33 and a second side (−Z) in the Z-axis direction from the base end portion of the rod-shaped portion 34. It has a first extending portion 35 extending to and a second extending portion 36 connecting the ends of the first extending portion 35 on the second side (−Z) in the Z-axis direction. With this structure, when a current is passed through at least one of the first coil 31 and the third coil 32, the first yoke 30 forms a closed magnetic path mp_X together with the gap Gp. Further, since this structure forms a region Ar2 in which the yoke and the coil are not arranged on the first side (+ Z) in the Z-axis direction from the rod-shaped portion including the first magnetic pole end 33, a magnetic field is applied to this region. It can be used as the area Ar2.

By passing a current through at least one of the first coil 31 and the third coil 32, a magnetic flux having only an X-axis direction component is generated in a predetermined region P on the central axis CL. As shown in FIG. 2, by passing a current (Xi +) through the first coil 31 and the third coil 32, a magnetic flux mf1 directed in the first direction (+ X) is generated on the central axis CL. On the contrary, if a current opposite to the current (Xi +) is passed through the first coil 31 and the third coil 32, the current (-X) opposite to the first direction (+ X) is formed on the central axis CL. A magnetic flux is generated.

As shown in FIG. 2, the pair of first magnetic pole end portions 33 are formed in a rod shape extending from the second side (−Z) to the first side (+ Z) from the base end side toward the tip end. If a magnetic field is generated between the magnetic poles 33a of the first magnetic pole end 33, a magnetic force may be generated in the direction in which the tip of the rod-shaped first magnetic pole end 33 faces the second side (-Z), and the first magnetism The extreme portion 33 may bend and deform.
Therefore, a non-magnetic support portion 5 that supports the pair of first magnetic pole end portions 33 from the second side (−Z) is provided. The support portion 5 may use a second extending portion 36 or a housing (not shown) for accommodating the electromagnet 1 as a scaffold.

The Z-axis electromagnet 4 has a second yoke 40 and a second coil 41 wound around the second yoke 40.

The second yoke 40 is made of a soft ferromagnet and is magnetically connected to the first yoke 30. The second yoke 40 has a rod-shaped portion 43 coaxial with the central axis CL. The magnetic pole 43a at the tip of the rod-shaped portion 43 faces the first side (Z +) in the Z-axis direction. When a current is passed through the second coil 41, a magnetic flux having only a Z-axis direction component is generated in a predetermined region P on the central axis CL. By changing the direction of the current flowing through the second coil 41, the direction of the magnetic flux generated on the central axis CL can be changed.

When a current is passed through at least one of the first coil 31 and the third coil 32 and the second coil 41 at the same time, it is possible to generate a magnetic field in the direction in which the X-axis component and the Z-axis component are combined. That is, by changing the direction and magnitude of the current flowing through at least one of the first coil 31 and the third coil 32 and the second coil 41, it is arbitrary on the XZ plane parallel to the X-axis direction and the Z-axis direction. A directional magnetic field can be applied on the central axis CL.

<Reduction configuration of Y-axis direction component>
As illustrated in FIG. 5, a leakage magnetic field having a Y-axis direction component is generated in a region Ar100 away from the central axis CL, but in order to reduce the leakage magnetic field (magnetic flux) having a Y-axis direction component, this embodiment Then, the following structure is adopted.

That is, as shown in FIGS. 1 to 3, the surface 37 on the first side (+ X) of each of the first magnetic pole end portions 33 has a pair of tapered surfaces 37a arranged on both sides in the Y-axis direction. In this embodiment, the surface 37 further has a flat surface 37b parallel to the XY plane arranged between the pair of tapered surfaces 37a. As shown in FIG. 3, each of the pair of tapered surfaces 37a is inclined from the center C1 in the Y-axis direction toward the outer end 33b from the first side (+ Z) to the second side (-Z) in the Z-axis direction. doing. That is, the tapered surface 37a goes from the center C1 and the first side (+ Z) to the outer end 33b and the second side (−Z). In the present embodiment, the pair of tapered surfaces 37a are flat surfaces, but the present invention is not limited thereto. For example, the tapered surface 37a may be a curved surface or a combination of a flat surface and a curved surface. As schematically shown by the alternate long and short dash line in FIG. 3, the tapered surface 37a has the effect of converting the leakage magnetic flux (magnetic flux) of the Y-axis direction component into the Z-axis direction component. Magnetic flux) can be reduced. In particular, as schematically shown in FIG. 1, the leakage magnetic field of the Y-axis direction component in the outer region of the uniform range Ar3 of the magnetic field of the X-axis direction component can be effectively reduced. In FIG. 1, it is possible to effectively reduce the leakage magnetic field of the Y-axis direction component in the region between the magnetic poles 33a and 33a and outside the uniform range Ar3 in the Y-axis direction. The uniform range Ar3 shown in FIG. 1 is merely exemplified for facilitating the understanding of the invention, and is not limited to the illustrated range. The uniform range Ar3 becomes wider or narrower than shown due to various factors such as the distance between the magnetic poles 33a on the X-axis and the shape of the magnetic poles, and FIG. 1 is merely an example.

In the embodiment shown in FIGS. 1 and 3, each of the first magnetic pole end portions 33 is formed in a T shape having a width W2 in the Y-axis direction at the tip wider than a width W1 in the Y-axis direction on the base end side. There is. With this configuration, the magnetic field strength of the component in the X-axis direction near the central axis CL can be secured by forming a T-shape having a wide tip width W1. Further, it is possible to improve the uniformity of the magnetic field of the component in the X-axis direction in the vicinity of the central axis CL.

<Reverse current mode>
As shown in FIG. 4, if the current supply unit 2 executes the current supply in the reverse current mode, the magnetic flux mf2 along the Z-axis direction can be generated on the central axis CL only by the X-axis electromagnet 3. In the reverse current mode, the current Xi + that generates the magnetic flux mf1 toward the first direction (+ X) on the central axis CL is passed through the first coil 31, and the second direction (-X) opposite to the first direction (+ X). In this mode, a current Xi− that generates a magnetic flux toward the central axis CL is passed through the third coil 32. When the current is passed in this way, the magnetic flux mf2 along the Z-axis direction is generated. The magnetic flux mf2 has only a Z-axis direction component in a predetermined region P on the central axis CL.

<Modification example>
(1-1) In the embodiment shown in FIG. 1, the T-shape has a tip width W2 wider than the base end side width W1 of the first magnetic pole end 33 in the Y-axis direction, but a target magnetic field is applied. If the area is small, it is not limited to this. For example, W1 ≧ W2 may be set.

(1-2) In the embodiment shown in FIGS. 1 to 3, the second coil 41 is provided, but if the magnetic field of the Z-axis component is generated by the reverse current mode, the second coil 41 may be omitted. It is possible.

(1-3) In the embodiment shown in FIGS. 1 to 4, both the first coil 31 and the third coil 32 are provided. However, either one of the first coil 31 and the third coil 32 can be omitted when the reverse current mode is not executed.

(1-4) In the embodiment shown in FIG. 2, a support portion 5 for supporting the first magnetic pole end portion 33 is provided, but the support portion 5 can be omitted. For example, there is a case where the first magnetic pole end 33 extends parallel to the X-axis direction.

(1-5) In the embodiment shown in FIGS. 1 to 4, the tip of the second yoke 40 is on the second side (−Z) of the surface 37b on the first side (+ Z) of the first magnetic pole end portion 33. positioned. Expressed in terms of the height in the Z-axis direction, the first yoke> the second yoke. In this way, it is possible to increase the ratio or ratio of the X-axis direction magnetic flux component to the Z-axis direction magnetic flux component as compared with the case of the first yoke ≤ second yoke. This can be said not only in the first embodiment but also in the second embodiment and the third embodiment. The surface 37b on the first side (+ Z) of the first magnetic pole end 33 may be flush with the tip of the second yoke 40. Expressed in terms of the height in the Z-axis direction, the first yoke = the second yoke. In this way, it is possible to increase the ratio or ratio of the Z-axis direction magnetic flux component to the X-axis direction magnetic flux component as compared with the case where the first yoke> the second yoke. This can be said not only in the first embodiment but also in the second embodiment and the third embodiment.

(1-6) In the embodiment shown in FIGS. 1 to 4, the surface 37 on the first side (+ X) of each first magnetic pole end 33 has a flat surface 37b parallel to the XY plane, but this is omitted. It is possible. That is, there may be no flat surface 37b where the pair of tapered surfaces 37a intersect and are parallel to the XY plane. For example, when the pair of tapered surfaces 37a are flat surfaces, they have a triangular shape when viewed from the side. If a flat surface 37b parallel to the XY plane is provided as shown in FIGS. 1 to 4, the uniform range of the magnetic field of the component in the X-axis direction becomes wider than in the case where the flat surface 37b is not provided, and other It is possible to avoid interference with the equipment.

As described above, in the electromagnet 1 of the first embodiment, the magnetic poles 33a at the tip are separated along the X-axis direction with the gap Gp in between, and are axially symmetric with each other about the central axis CL parallel to the Z-axis direction. A first yoke 30 having a pair of first magnetic pole end portions 33 arranged at positions and capable of forming a closed magnetic path mp_X together with a gap Gp, a first coil 31 wound around the first yoke 30, and a central axis CL. With a second yoke 40 which has a rod-shaped portion 43 coaxial with the rod-shaped portion 43, the magnetic pole 43a at the tip of the rod-shaped portion 43 faces the first side (+ Z) in the Z-axis direction, and is magnetically connected to the first yoke 30. , And the surface 37 on the first side (+ Z) of the tip of each first magnetic pole end 33 has a pair of tapered surfaces 37a arranged on both sides in the Y-axis direction, and a pair of tapered surfaces 37a. Are inclined from the center C1 in the Y-axis direction toward the outer end 33b from the first side (+ Z) in the Z-axis direction to the second side (-Z) opposite to the first side (+ Z). doing.
According to this configuration, the pair of tapered surfaces converts the leakage magnetic field of the Y-axis direction component generated between the 33 pairs of magnetic poles of the first magnetic pole end portions into the magnetic field of the Z-axis direction component by energizing the first coil 31. Therefore, it is possible to reduce the leakage magnetic field having a Y-axis direction component generated from the magnetic pole pair of the first magnetic pole end portion 33.

As in the first embodiment shown in FIGS. It is preferably formed.
According to this configuration, the magnetic field strength of the component in the X-axis direction near the central axis CL can be secured by forming a T-shape having a wide tip width W1. Further, it is possible to improve the uniformity of the magnetic field of the component in the X-axis direction in the vicinity of the central axis CL.

As in the first embodiment shown in FIGS. 1 to 4, a second coil 41 wound around the second yoke 40 is further provided, and the current flowing through the first coil 31 and the second coil 41 is changed to change the current flowing in the X-axis direction. It is preferable that a magnetic field in an arbitrary direction on the XZ plane parallel to the Z-axis direction can be applied on the central axis CL.
According to this configuration, the direction and strength of the magnetic field of the Z-axis direction component can be controlled by energizing the second coil 41. Further, a magnetic field in an arbitrary direction in which a X-axis direction component and a Z-axis direction component are combined can be applied.

As in the first embodiment shown in FIGS. A current (Xi +) generated on the CL is passed through the first coil 31, and a magnetic flux is generated on the central axis CL in the second direction (-X) opposite to the first direction (+ X). It is preferable that the magnetic flux mf2 having a Z-axis direction component can be expressed on the central axis CL by flowing −) through the third coil 32.
According to this configuration, the magnetic field of the Z-axis direction component can be generated by the first yoke 30 in the reverse current mode.

As in the first embodiment shown in FIGS. 1 to 4, the pair of first magnetic pole end portions 33 have a rod shape extending from the second side (−Z) to the first side (+ Z) from the base end side toward the tip end. It is preferable that the electromagnet 1 is further provided with a non-magnetic support portion 5 that supports the pair of first magnetic pole end portions 33 from the second side (−Z).
Since the first magnetic pole end portion 33 bends to the second side (−Z) due to the magnetic force, the support portion 5 can prevent the first magnetic pole end portion 33 from bending and deforming.

[Second Embodiment]
Hereinafter, the second embodiment of the present disclosure will be described with reference to FIGS. 6 to 8. Unlike the first embodiment, the second embodiment is not an embodiment corresponding to the problem of reducing the leakage magnetic field having a Y-axis direction component. The second embodiment corresponds to the problem of strengthening the magnetic field in the Z-axis direction in an electromagnet configured to be able to apply a magnetic field in an arbitrary direction on an XZ plane parallel to the X-axis direction and the Z-axis direction.

<Magnetic field application system>
FIG. 6 is a schematic plan view showing an electromagnet 101 constituting a magnetic field application system. The magnetic field application system is configured to generate a magnetic field in an arbitrary direction on the XZ plane parallel to the X-axis direction and the Z-axis direction on the central axis so that the magnetic field can be applied to the object to be applied. The arbitrary direction does not include the Y-axis direction. As shown in FIG. 6, the magnetic field application system includes an electromagnet 101 and a current supply unit 102 that supplies a current to the electromagnet 101. The X-axis direction, the Y-axis direction, and the Z-axis direction are directions orthogonal to each other, and are used for facilitating the description of the invention. Since the orientation of the electromagnet 101 differs depending on the method of use, it is not limited to the orientation shown in the drawings of the present disclosure.

<Electromagnet>
As shown in FIGS. 6 and 7, the electromagnet 101 includes an X-axis electromagnet 103 for generating a magnetic field of an X-axis direction component, a Z-axis electromagnet 104 for generating a magnetic field of a Z-axis direction component, and the like. Has.

The X-axis electromagnet 103 has a first yoke 130, and a first coil 131 and a third coil 132 wound around the first yoke 130.

The first yoke 130 is made of a soft ferromagnet, has a pair of first magnetic pole end portions 133 in which the magnetic pole 133a at the tip is separated along the X-axis direction with the gap Gp in between, and is magnetically closed together with the gap Gp. The path mp_X can be formed. As shown in FIG. 6, the pair of first magnetic pole end portions 133 are arranged at positions symmetrical with each other about the central axis CL parallel to the Z-axis direction. As a result, a magnetic flux parallel to the XY plane can be generated on the central axis CL. In the present embodiment, the first yoke 130 is C-shaped in side view, but is not limited thereto. The first magnetic pole end portion 133 is provided at the tip of the rod-shaped portion 134. The rod-shaped portion 134 has a shape extending in a straight line, but is not limited to this as long as it has a long shape. For example, a shape that extends while bending or a shape that extends in a curved shape may be used. In the present embodiment, as shown in FIG. 7, the first yoke 130 has a rod-shaped portion 134 including the first magnetic pole end portion 133 and a second side (−Z) in the Z-axis direction from the base end portion of the rod-shaped portion 134. It has a first extending portion 135 extending to and a second extending portion 136 connecting the ends of the first extending portion 135 on the second side (−Z) in the Z-axis direction. With this structure, when a current is passed through at least one of the first coil 131 and the third coil 132, the first yoke 130 forms a closed magnetic path mp_X together with the gap Gp. Further, since this structure forms a region Ar2 in which the yoke and the coil are not arranged on the first side (+ Z) in the Z-axis direction from the rod-shaped portion including the first magnetic pole end portion 133, a magnetic field is applied to this region. It can be used as the area Ar2.

As shown in FIG. 6, each of the 133 pairs of the first magnetic pole ends of the first yoke 130 is formed in a shape that tapers from the base end side toward the tip end. This is to strengthen the magnetic force of the component in the X-axis direction.

By passing a current through at least one of the first coil 131 and the third coil 132, a magnetic flux having only an X-axis direction component is generated in a predetermined region P on the central axis CL. As shown in FIG. 7, by passing a current (Xi +) through the first coil 131 and the third coil 132, a magnetic flux mf1 directed in the first direction (+ X) is generated on the central axis CL. On the contrary, if a current opposite to the current (Xi +) is passed through the first coil 131 and the third coil 132, the current (-X) opposite to the first direction (+ X) is formed on the central axis CL. A magnetic flux is generated.

The Z-axis electromagnet 104 has a second yoke 140 and a second coil 141 wound around the second yoke 140.

The second yoke 140 is made of a soft ferromagnet and is magnetically connected to the first yoke 130. The second yoke 140 has a rod-shaped portion 143 coaxial with the central axis CL. The magnetic pole 143a at the tip of the rod-shaped portion 143 faces the first side (Z +) in the Z-axis direction. When a current is passed through the second coil 141, a magnetic flux having only a Z-axis direction component is generated in a predetermined region P on the central axis CL. By changing the direction of the current flowing through the second coil 141, the direction of the magnetic flux generated on the central axis CL can be changed.

When a current is passed through the first coil 131 and the second coil 141 at the same time, it is possible to generate a magnetic field in the direction in which the X-axis component and the Z-axis component are combined. That is, by changing the direction and magnitude of the current flowing through the first coil 131 and the second coil 141, a magnetic field in an arbitrary direction on the XZ plane parallel to the X-axis direction and the Z-axis direction is applied on the central axis CL. It is possible.

As shown in FIG. 6, the distance between the magnetic poles of the first magnetic pole end portion 133 in the radial direction of the central axis CL is indicated by L1. No yoke pairs other than the first yoke 130 and the second yoke 140 are arranged in the first region Ar1 which is a circular region having a radius R1 larger than L1 about the central axis CL. Further, it is preferable that the radius R1 is larger than L1 × 1.5. As described above, since the magnetic pole pairs of the yokes other than the first yoke 130 and the second yoke 140 are not arranged in the first region Ar1, the magnetic field in an arbitrary direction on the XZ plane can be appropriately applied.

<Strengthening configuration of Z-axis magnetic field>
The electromagnet 101 of the second embodiment adopts the following configuration in order to strengthen the magnetic field in the Z-axis direction.

That is, as shown in FIGS. 6 to 8, a third yoke 160 that is magnetically connected to the second yoke 140 is provided. The third yoke 160 has a pair of third magnetic pole end portions 163 arranged at positions symmetrical with each other about the central axis CL. The magnetic poles 163a at the tip of the third magnetic pole end portion 163 are separated from each other along the Y-axis direction passing through the central axis CL.

Specifically, the base end portion of the third yoke 160 is connected to the second extending portion 136 of the first yoke 130, whereby the third yoke 160 connects the second extending portion 136 of the first yoke 130. It is magnetically connected to the second yoke 140 via. The third yoke 160 extends outward from the base end in the Y-axis direction, then extends to the first side (+ Z) in the Z-axis direction, and then extends inward in the Y-axis direction, and the tip portion forms a magnetic pole. doing. The magnetic pole 163a is an arc-shaped end along a radius R2 centered on the central axis CL. R2> R1.

No coil is wound around the third yoke 160. The third yoke 160 is provided to serve as a return yoke for returning the magnetic flux in the Z-axis direction emitted from the second yoke 140 to the second yoke 140, and it is not necessary to wind a coil around the third yoke 160. Is. As shown in FIG. 6, the magnetic pole 163a at the tip of the third magnetic pole end portion 163 of the third yoke 160 is arranged outside the first region Ar1. By satisfying such a condition, the third yoke 160 functions as a return yoke, and the magnetic field of the Z-axis direction component can be strengthened.

In order to prevent the third yoke 160 from obstructing the generation of the magnetic field in the X-axis direction and the magnetic field in the Z-axis direction, as shown in FIGS. 6 and 8, the magnetic pole 163a at the tip of the third magnetic pole end portion 163 It is preferable that the shortest distance Mi1 from the first yoke 130 to the first yoke 130 is longer than L1, and the shortest distance Mi2 from the magnetic pole 163a at the tip of the third magnetic pole end portion 163 to the second yoke 140 is longer than L1.

As shown in FIG. 8, the tip 143b of the rod-shaped portion 143 of the second yoke 140 projects to the first side (+ Z) from the surface 163b on the first side (+ Z) of the third magnetic pole end portion 163. According to this configuration, since the third yoke 160 is not arranged in the radial outer region of the central axis CL of the tip 143 of the second yoke 140, interference with other devices can be avoided, and the convenience of the electromagnet can be improved. It is possible to improve.

In the second embodiment, the reverse current mode described in the first embodiment can be applied.

<Modification example>
(1-1) In the embodiment shown in FIGS. 6 to 8, the tip 143b of the second yoke 140 is on the first side (+ Z) of the surface 163b on the first side (+ Z) of the third magnetic pole end portion 163. It stands out, but you can change it. For example, the following configurations A and B can be considered.
The configuration A is a configuration in which the tip 143b of the second yoke 140 and the surface 163b on the first side (+ Z) of the third magnetic pole end portion 163 are flush with each other. In this way, the ratio or ratio of the Z-axis direction magnetic flux component to the X-axis direction magnetic flux component can be made higher than that of the following configuration B.
In the configuration B, the surface 163b on the first side (+ Z) of the third magnetic pole end portion 163 is projected to the first side (+ Z) from the tip 143b of the second yoke 140. In this way, the ratio or ratio of the X-axis direction magnetic flux component to the Z-axis direction magnetic flux component can be made higher than that of the above configuration A.

(1-2) In the embodiment shown in FIGS. 6 to 8, the second coil 141 is provided, but if the magnetic field of the Z-axis component is generated by the reverse current mode, the second coil 141 may be omitted. It is possible.

(1-3) In the embodiment shown in FIGS. 6 to 8, both the first coil 131 and the third coil 132 are provided. However, either one of the first coil 131 and the third coil 132 can be omitted when the reverse current mode is not executed.

[Third Embodiment]
Hereinafter, the third embodiment of the present disclosure will be described with reference to FIG. The third embodiment is a configuration in which the third yoke 160 is removed from the second embodiment. The same members as those in the second embodiment are designated by the same reference numerals, and the description thereof will be omitted. As shown in FIG. 9, the electromagnet 201 has a magnetic pole pair of a yoke other than the first yoke 130 and the second yoke 140 in the first region Ar1 which is a circular region having a radius R1 larger than L1 about the central axis CL. Is not placed. Further, yokes other than the first yoke 130 and the second yoke 140 are arranged at positions parallel to the Y-axis direction and the Z-axis direction and overlapping the YZ plane (denoted as Pyz in FIG. 9) passing through the central axis CL. Not. Further, the radius R1 is preferably larger than L1 × 1.5.

As described above, in the electromagnets 101 and 201 of the second and third embodiments, the magnetic poles 133a at the tip are separated along the X-axis direction with the gap Gp in between, and the central axis CL parallel to the Z-axis direction is the center. A first yoke 130 having a pair of first magnetic pole end portions 133 arranged at positions symmetrical with each other and capable of forming a closed magnetic path mp_X together with a gap Gp, and a first coil 131 wound around the first yoke 130. A second yoke 140 magnetically connected to the first yoke 130 and having a rod-shaped portion coaxial with the central axis CL, and a second coil 141 wound around the second yoke 140 are provided, and the diameter of the central axis CL is provided. In the first region Ar1, which is a circular region in which the distance between the magnetic poles of the first magnetic pole end 133 in the direction is L1 and the radius R1 is larger than L1 about the central axis CL, other than the first yoke 130 and the second yoke 140. The magnetic pole pair of the yoke is not arranged.
As described above, since the magnetic pole pairs of the yokes other than the first yoke 130 and the second yoke 140 are not arranged in the first region Ar1, the magnetic field in an arbitrary direction on the XZ plane can be appropriately applied.

As in the second embodiment, a third yoke 160 magnetically connected to the second yoke 140 is further provided, and the third yoke 160 is separated along the Y-axis direction in which the magnetic pole 163a at the tip passes through the central axis CL. However, it has a pair of third magnetic pole end portions 163 arranged at positions symmetrical with each other about the central axis CL, and a coil is not wound around the third yoke 160, and the third magnetic pole end portion is formed. The magnetic pole 163a at the tip of the 163 is preferably arranged outside the first region Ar1.
By providing the third yoke 160 as the return yoke and satisfying the above conditions in this way, it is possible to strengthen the magnetic field of the Z-axis direction component generated from the second yoke 140 by the third yoke 160.

As in the second embodiment, the magnetic pole 143a at the tip of the rod-shaped portion 143 of the second yoke 140 faces the first side (+ Z) in the Z-axis direction, and the tip 143b of the rod-shaped portion 143 of the second yoke 140 faces. It is preferable that the third magnetic pole end portion 163 protrudes to the first side (+ Z) from the surface 163b on the first side (+ Z).
According to this configuration, since the third yoke 160 is not arranged in the radial outer region of the central axis CL of the tip 143 of the second yoke 140, interference with other devices can be avoided, and the convenience of the electromagnet can be improved. It is possible to improve.

As in the third embodiment, yokes other than the first yoke 130 and the second yoke 140 are arranged at positions parallel to the Y-axis direction and the Z-axis direction and overlapping the YZ plane (Pyz) passing through the central axis CL. It is preferable not to.
According to this configuration, it is possible to obtain a region in which the yokes are not arranged on both sides of the first yoke 130 and the second yoke 140 in the Y-axis direction. 201 can be provided.

As in the second and third embodiments, a third coil 132, which is wound around the first yoke 130 and is different from the first coil 131, is further provided, and a magnetic flux mf1 directed in the first direction (+ X) is placed on the central axis CL. The current (Xi-) to be generated is passed through the first coil 131, and the magnetic flux to be generated in the second direction (-X) opposite to the first direction (+ X) is generated on the central axis CL. It is preferable that the magnetic flux mf2 having a Z-axis direction component can be expressed on the central axis CL by flowing the current through the third coil 132.
According to this configuration, the magnetic field of the Z-axis direction component can be generated by the first yoke 130 in the reverse current mode.

[Fourth Embodiment]
Hereinafter, the first example, the second example, and the third example of the fourth embodiment of the present disclosure will be described with reference to FIGS. 10 to 12. The tasks of the fourth embodiment are different from the tasks of the first to third embodiments. The fourth embodiment corresponds to the task of controlling the ratio or ratio of the Z-axis direction magnetic flux component to the other direction magnetic flux component.

In the first example of the fourth embodiment shown in FIG. 10A, the shape of the second yoke 40 of the first embodiment shown in FIGS. 1 to 4 is changed, and there is no other change. As shown in FIG. 10A, the tip of the rod-shaped portion 43'of the second yoke 40' faces the first side (+ Z) in the Z-axis direction. The tip 43a'of the rod-shaped portion 43'of the second yoke 40'projects to the first side (+ Z) from the surface 37b on the first side (+ Z) of the first magnetic pole end portion 33. Expressed in terms of the height in the Z-axis direction, the first yoke <the second yoke.

The second example of the fourth embodiment shown in FIG. 10B is a modification of the shape of the second yoke 140 of the second and third embodiments shown in FIGS. 6 to 9, and there is no other change. As shown in FIG. 10B, the tip of the rod-shaped portion 143'of the second yoke 140' faces the first side (+ Z) in the Z-axis direction. The tip 143a'of the rod-shaped portion 143'of the second yoke 140' projects toward the first side (+ Z) from the surface 137b on the first side (+ Z) of the first magnetic pole end portion 133. Expressed in terms of the height in the Z-axis direction, the first yoke <the second yoke.

According to the configurations shown in FIGS. 10A and 10B, in the electromagnet configured to be able to apply a magnetic flux in an arbitrary direction on the XZ plane parallel to the X-axis direction and the Z-axis direction, the first yoke ≧ Compared with the case of the second yoke, the ratio or ratio of the Z-axis direction magnetic flux component to the X-axis direction magnetic flux component can be increased.

The third example of the fourth embodiment shown in FIGS. 11 and 12 is an electromagnet 301 configured to be able to apply a magnetic field in an arbitrary direction having at least one directional component in the X-axis direction, the Y-axis direction, and the Z-axis direction. show. The electromagnet 301 has a first yoke 330, a second yoke 340, a third yoke 350, a coil 331 wound around the first yoke 330, and a coil 351 wound around the third yoke 350. The electromagnet 301 may have a coil wound around the second yoke 340. The first yoke 330 is a pair of magnetic poles 333a at the tip thereof, which are separated from each other along the X-axis direction with a gap Gp in between, and are arranged at positions axisymmetric with each other about the central axis CL parallel to the Z-axis direction. It has a first magnetic pole end portion 333 and can form a closed magnetic path together with the gap Gp. The second yoke 340 has a rod-shaped portion 343 coaxial with the central axis CL, and the tip of the rod-shaped portion 343 faces the first side (+ Z) in the Z-axis direction and is magnetically connected to the first yoke 330. NS. The third yoke 350 is a pair of third magnetic pole end portions 353 arranged at positions where the magnetic poles 353a at the tip thereof are separated along the Y-axis direction with a gap Gp sandwiched between them and are axially symmetric with each other about the central axis CL. It is possible to form a closed magnetic path together with the gap Gp. The tip 343a of the rod-shaped portion 343 of the second yoke 340 is from the surface 37b (137b; 337b) of the first side (+ Z) of the first magnetic pole end 33 (133; 333) of the first yoke 30 (130; 330). Also protrudes to the first side (+ Z).

According to the configurations of FIGS. 11 and 12, in an electromagnet configured to be able to apply a magnetic field in an arbitrary direction having at least one directional component in the X-axis direction, the Y-axis direction, and the Z-axis direction, the first yoke ≥ the second Compared with the case of the yoke, it is possible to increase the ratio or ratio of the Z-axis direction magnetic flux component to the X-axis direction magnetic flux component and the Y-axis direction magnetic flux component.

As described above, the electromagnets of the fourth embodiment are positioned so that the magnetic poles at the tips thereof are separated along the X-axis direction with the gap Gp in between and are axially symmetrical with each other about the central axis CL parallel to the Z-axis direction. A first yoke 30 (130; 330) and a first yoke 30 (130; 330) having a pair of arranged first magnetic pole end portions 33 (133; 333) and capable of forming a closed magnetic path together with a gap Gp. It has a first coil wound around and a rod-shaped portion 43'(143'; 343) coaxial with the central axis CL, and the tip of the rod-shaped portion 43'(143'; 343) is the first side (+ Z) in the Z-axis direction. A second yoke 40'(140'; 340) magnetically connected to the first yoke 30 (130; 330), and the second yoke 40'(140'; 340). The tip 43a'(143a'; 343a) of the rod-shaped portion 43'(143'; 343) is the first side (+ Z) of the first magnetic pole end 33 (133; 333) of the first yoke 30 (130; 330). It is preferable that the surface 37b (137b; 337b) protrudes toward the first side (+ Z).

Although the embodiments of the present disclosure have been described above with reference to the drawings, it should be considered that the specific configuration is not limited to these embodiments. The scope of the present invention is shown not only by the description of the above-described embodiment but also by the scope of claims, and further includes all modifications within the meaning and scope equivalent to the scope of claims.

It is possible to adopt the structure adopted in each of the above embodiments in any other embodiment. The specific configuration of each part is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

1, 101, 201 Electromagnet 2 Current supply unit 30, 130 1st yoke 31, 131 1st coil 32, 132 3rd coil 33, 133 1st magnetic pole end 37a Tapered surface 40, 140 2nd yoke 41, 141 2nd Coil 43, 143 Rod-shaped part of 2nd yoke 5 Support part Gp gap CL Central axis + Z 1st side −Z 2nd side

Claims (8)

It has a pair of rod-shaped portions and a pair of first magnetic pole end portions provided at the tips of the pair of rod-shaped portions. A first yoke that is separated and is arranged at a position that is axisymmetric with each other about a central axis parallel to the Z-axis direction and can form a closed magnetic path together with the gap.
The first coil wound around the first yoke and
A second yoke that is magnetically connected to the first yoke and has a rod-shaped portion coaxial with the central axis.
The second coil wound around the second yoke and
With
The magnetic pole pairs of the yokes other than the first yoke and the second yoke are not arranged in the first region which is a circular region having a radius R1 about the central axis, and the radius R1 is the central axis. An electromagnet that is larger than the distance L1 between the magnetic poles of the first magnetic pole end in the radial direction. The tip of the rod-shaped portion of the second yoke faces the first side in the Z-axis direction.
The first aspect of the first yoke, wherein the tip of the rod-shaped portion on the inner side of the central axis in the radial direction extends toward the first side from the base end portion on the outer side in the radial direction of the central axis. Electromagnet. The first or second aspect of the present invention, wherein the yokes other than the first yoke and the second yoke are not arranged at positions parallel to the Y-axis direction and the Z-axis direction and overlapping the YZ plane passing through the central axis. electromagnet. A third yoke that is magnetically connected to the second yoke is further provided.
The third yoke has a pair of third magnetic pole ends arranged at positions where the magnetic poles at the tip are separated along the Y-axis direction passing through the central axis and are axially symmetric with each other about the central axis. death,
The electromagnet according to claim 1 or 2, wherein a coil is not wound around the third yoke, and the magnetic pole at the tip of the third magnetic pole end is arranged outside the first region. A third coil different from the first coil, which is wound around the first yoke, is further provided.
A current that causes a magnetic flux in the first direction to be generated on the central axis is passed through the first coil, and a current that generates a magnetic flux in the second direction opposite to the first direction is generated on the central axis. The electromagnet according to any one of claims 1 to 4, wherein a magnetic flux having a Z-axis direction component can be generated on the central axis by flowing the electric current through the third coil. The tip of the rod-shaped portion of the second yoke faces the first side in the Z-axis direction.
The tip of the rod-shaped portion of the second yoke is flush with the surface of the first magnetic pole end of the first yoke on the first side, or the tip of the first magnetic pole end of the first yoke. The electromagnet according to any one of claims 1 to 5, which protrudes toward the first side from the surface on the first side. The tip of the rod-shaped portion of the second yoke faces the first side in the Z-axis direction.
The tip of the rod-shaped portion of the second yoke is a second side opposite to the first side in the Z-axis direction with respect to the surface of the first magnetic pole end portion of the first yoke on the first side. The electromagnet according to any one of claims 1 to 5, which is located in. The electromagnet according to any one of claims 1 to 7 and
A magnetic field application system including a current supply unit that supplies a current to each coil of the electromagnet.

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