JP2020148326A - Torque generator - Google Patents

Abstract

To provide a torque generator that may form magnetic circuit through which magnetic lines of force pass through a wider area and may make magnetic field acting on a ferrofluid in the radial direction of a cylindrical rotating body substantially uniform over a wide range.SOLUTION: An inner yoke includes a plurality of facing parts having an outer peripheral surface facing an inner peripheral surface of the cylindrical part, and is arranged so as to be relatively rotatable with respect to an outer yoke with the central axis of the cylindrical part as the center of rotation. The gaps where the outer peripheral surfaces of the facing parts and the inner peripheral surfaces of the outer yoke face each other are filled with a magnetic viscous fluid. A magnetic field generating part arranged inside the plurality of facing parts of the inner yoke is controlled by a control unit so as to generate magnetic field that forms one magnetic circuit including a magnetic field line from one outer peripheral surface of the plurality of facing parts of the inner yoke to the inner peripheral surface of the facing outer yoke and a magnetic field line from the inner peripheral surface of the outer yoke to another outer peripheral surface of the plurality of facing parts of the inner yoke. The plurality of facing parts are arranged side by side along the circumferential direction of the cylindrical part.SELECTED DRAWING: Figure 2

Description

The present invention relates to a torque generator capable of changing rotational resistance using a ferrofluid.

The tactile interface described in Patent Document 1 includes a configuration in which a cylindrical rotating body is arranged in a chamber filled with a ferrofluid. The chamber is surrounded by magnetic material, both inside and outside. Inside the chamber, a coil wound in the circumferential direction around the axis of the rotating body is arranged, and the magnetic field generated by the magnetic field generation system including this coil is the diameter of the rotating body with respect to the ferrofluid. Act in the direction.

The rotation transmission device described in Patent Document 2 includes a configuration in which a cylindrical rotating body is provided so as to be relatively rotatable between an outer cylinder portion and an inner cylinder portion of a rotor case. A magnetic viscous fluid is provided in the gap between the rotating body and the outer cylinder portion and in the gap between the rotating body and the inner cylinder portion. On the outside of the rotor case, a plurality of coils wound in a plane along the circumferential direction are arranged around an axis along the radial direction, and the magnetic field generated by the electromagnet including these coils is magnetically viscous. It acts on the fluid in the radial direction of the rotating body.

Special Table 2011-510099 Japanese Unexamined Patent Publication No. 2016-109207

However, both the tactile interface described in Patent Document 1 and the rotation transmission device described in Patent Document 2 generate a magnetic field along the radial direction of the cylindrical rotating body, but are radially relative to the magnetic viscous fluid. Since there is a wide region where there are few lines of magnetic force acting on it, it has been difficult to increase the upper limit of the magnitude of the rotational resistance received by the rotating body. More specifically, in the tactile interface described in Patent Document 1, the number of lines of magnetic force in the region where the coil is provided in the axial direction tends to decrease, and in the rotation transmission device described in Patent Document 2, the coil is arranged in the circumferential direction. The number of magnetic field lines in the region tends to decrease, and the number of magnetic field lines in the region where the coil is not arranged between the adjacent electromagnets tends to decrease.

Therefore, according to the present invention, by forming a magnetic circuit through which magnetic lines of force pass through a wider region, the magnetic field acting on the ferrofluid in the radial direction of the cylindrical rotating body can be substantially made uniform in a wide range. An object of the present invention is to provide a torque generator capable of increasing the resistance (torque) of a ferrofluid to a rotating body.

In order to solve the above problems, the torque generator of the present invention is a torque generator including an outer yoke having a cylindrical portion and an internal yoke arranged inside the cylindrical portion, and the internal yoke is a cylindrical portion. It is provided with a plurality of facing portions having an outer peripheral surface facing the inner peripheral surface of the cylinder, and is arranged so as to be rotatable relative to the outer yoke with the central axis of the cylindrical portion as the center of rotation. The gaps facing the inner peripheral surfaces of the yoke are filled with magnetic viscous fluid, and the magnetic field generating part is arranged inside the plurality of facing parts of the inner yoke. The magnetic field generating part is controlled by the control unit and is inside. A magnetic field line from one outer peripheral surface of the plurality of opposing portions of the yoke to the inner peripheral surface of the outer yoke facing each other, and a magnetic field line from the inner peripheral surface of the outer yoke to another outer peripheral surface of the plurality of opposing portions of the inner yoke. It is characterized in that a magnetic field forming one magnetic circuit including, is generated, and a plurality of facing portions are arranged side by side along the circumferential direction of the cylindrical portion.
As a result, a magnetic circuit through which magnetic lines of force pass through a wider area can be formed. Therefore, the magnetic field acting on the ferrofluid in the radial direction of the outer yoke as a cylindrical rotating body can be substantially made uniform over a wide range. Can be done. This makes it possible to increase the resistance (torque) of the ferrofluid to the outer yoke or the inner yoke arranged inside the outer yoke.

In the torque generator of the present invention, the internal yoke includes a core portion extending along the radial direction of the cylindrical portion so as to connect two facing portions symmetrically arranged about the central axis of the plurality of facing portions. The magnetic field generating portion is a coil wound around the core portion with a virtual axis in the radial direction, and it is preferable that the coil is energized by the control unit.
As a result, the number of windings of the coil can be increased, and the lines of magnetic force along the radial direction can be substantially made uniform in a wide range.

In the torque generator of the present invention, the internal yoke includes at least a first internal yoke and a second internal yoke, and the first internal yoke has two first facing portions symmetrically arranged about a central axis. A first core portion extending along the first radial direction of the cylindrical portion so as to connect the two first facing portions, and a first radial direction wound around the first core portion as a virtual axis. The second inner yoke has a second diameter of a cylindrical portion that connects two second facing portions symmetrically arranged about a central axis and two second facing portions. It includes a second core portion extending along the direction and a second coil wound around the second core portion with the second radial direction as a virtual axis, and the second radial direction is based on the central axis. The two first facing portions and the two second facing portions are alternately arranged side by side along the circumferential direction, and are the first in the central axis direction of the cylindrical portion. It is preferable that the 1st core portion and the 2nd core portion are arranged at different positions.
As a result, the magnetic field lines can be passed through a wide range in the central axis direction of the outer yoke, the strength of the magnetic field can be increased, and more uniform can be achieved.

In the torque generator of the present invention, the magnetic field generating portion passes through the first core portion and passes from the outer peripheral surface of one of the two first facing portions of the first inner yoke to the inner peripheral surface of the facing outer yoke. The first line of magnetic force to go, the first line of magnetic force that passes through the outer yoke in the circumferential direction in succession to the first line of magnetic force, and the two second opposing portions from the inner peripheral surface of the outer yoke to the second inner yoke. The outer peripheral surface of the other of the two second opposing portions of the second inner yoke, which passes through the second core portion in succession to the second magnetic field line toward the outer peripheral surface of one of them and the second magnetic field line. A third line of magnetic force from the outer yoke toward the inner peripheral surface of the outer yoke, a second external magnetic field line passing through the outer yoke in the circumferential direction in succession to the third magnetic field line in the outer yoke, and an inner peripheral surface of the outer yoke. It is preferable to generate a magnetic field forming one magnetic circuit including a fourth magnetic field line extending from the first to the outer peripheral surface of the other of the two opposing portions of the first inner yoke and reaching the first core portion.
As a result, the magnetic field lines can be passed through a wide range in the central axis direction of the outer yoke, the strength of the magnetic field can be increased, and more uniform can be achieved.

In the torque generator of the present invention, the internal yoke includes a core portion extending along the central axis direction of the cylindrical portion so as to connect a plurality of facing portions, and the magnetic field generating portion is in the central axial direction with respect to the core portion. It is preferable that the coil is wound around the virtual shaft and the coil is energized by the control unit.
As a result, the number of windings of the coil can be increased, and the lines of magnetic force along the radial direction can be substantially made uniform in a wide range.

In the torque generator of the present invention, the internal yoke includes connecting portions that are connected to each of the plurality of facing portions and spread in the radial direction, and both ends in the central axial direction of the core portion are connected to the connecting portions, respectively, to generate a magnetic field. With a first magnetic field line passing through the core portion in the direction of the central axis, passing through one of the connecting portions, and going from the outer peripheral surface of one of the plurality of opposing portions of the inner yoke to the inner peripheral surface of the facing outer yoke. A second magnetic field line extending from the inner peripheral surface of the outer yoke to another outer peripheral surface of the plurality of opposing portions of the inner yoke, passing through the other one of the connecting portions, and reaching the core portion in the central axial direction. It is preferable to generate a magnetic field that forms one magnetic circuit including.
As a result, the magnetic field lines can be developed on the outer peripheral surface facing the outer yoke, so that a substantially uniform magnetic field can be formed with a wide range of the inner peripheral surface of the outer yoke.

In the torque generator of the present invention, it is preferable that the outer peripheral surfaces of the plurality of facing portions have a shape along the circumferential direction.
As a result, the distance from the inner peripheral surface of the outer yoke can be made uniform, so that a uniform magnetic field line can be given to the magnetically viscous fluid arranged in the gap.

According to the present invention, the magnetic field acting on the ferrofluid in the radial direction of the cylindrical rotating body can be made substantially uniform over all regions, whereby the resistance force of the ferrofluid to the rotating body ( It is possible to provide a torque generator capable of increasing the torque).

(A) is a perspective view of the torque generator according to the first embodiment as viewed from above, and (b) is a functional block diagram showing a control system of the torque generator shown in (a). It is an exploded perspective view of the torque generator of 1st Embodiment. It is sectional drawing in the line AA'in FIG. 1 (a). It is a top view which shows the arrangement of the inner yoke and the outer yoke in the torque generator of 1st Embodiment. (A) is a perspective view of the torque generator according to the second embodiment as viewed from above, and (b) is a functional block diagram showing a control system of the torque generator shown in (a). It is an exploded perspective view of the torque generator of the 2nd Embodiment. 5 is a cross-sectional view taken along the line BB'of FIG. 5A. (A) is a plan view showing the arrangement of the first rotor and the outer yoke in the torque generator of the second embodiment, and (b) is a plan view showing the arrangement of the second rotor and the outer yoke. FIG. 5 is a plan view showing the torque generator of the second embodiment excluding the first fixing plate and the first shaft portion. (A) is a perspective view of the torque generator according to the third embodiment as viewed from above, and (b) is a functional block diagram showing a control system of the torque generator shown in (a). It is an exploded perspective view of the torque generator of the 3rd Embodiment. FIG. 3 is a cross-sectional view taken along the line CC'of FIG. 10 (a). It is sectional drawing in the DD'line of FIG.

Hereinafter, the torque generator according to the embodiment of the present invention will be described in detail with reference to the drawings.
<First Embodiment>
FIG. 1A is a perspective view of the torque generator 10 according to the first embodiment as viewed from above, and FIG. 1B is a functional block diagram showing a control system of the torque generator 10. FIG. 2 is an exploded perspective view of the torque generator 10, and FIG. 3 is a cross-sectional view taken along the line AA'of FIG. 1A. FIG. 4 is a plan view showing the arrangement of the inner yoke 30 and the outer yoke 50 in the torque generator 10.

In each figure, for convenience of explanation, the vertical direction is defined along the rotation axis AX, but the direction in actual use is not limited. The direction along the rotation axis AX is referred to as an axial direction or a vertical direction, and the direction orthogonal to the rotation axis AX from the rotation axis AX is referred to as a radial direction. In the following description, the state of looking from the upper side to the lower side along the rotation axis AX may be referred to as a plan view, and in the plan view, the circumferential direction is the direction along the circumference of the circle centered on the rotation axis AX. It is called.

As shown in FIGS. 2 and 3, in the torque generator 10 according to the first embodiment, two shaft portions 21 and 22 arranged vertically are used, and an internal yoke 30 is provided between these shaft portions. A rotor provided with the exciting coil 41 is fixed. The external member arranged on the outside of the rotor includes an external yoke 50 and a pair of fixing plates 61 and 62.

The two shaft portions 21 and 22 are made of a non-magnetic material, and are integrated with each other via an internal yoke 30 and an exciting coil 41 arranged between them in the axial direction of the rotating shaft AX (the central axis direction of the external yoke 50). It has been transformed. The two shaft portions 21 and 22 can rotate about the rotation shaft AX together with the internal yoke 30 and the exciting coil 41. Therefore, the internal yoke 30 and the exciting coil 41 rotate around the rotation axis AX as a rotor.

The first shaft portion 21 arranged on the upper side in the axial direction includes a shaft portion 21a extending along the axial direction and a disk portion 21b extending in the radial direction from the lower end of the shaft portion 21a. Similarly, the second shaft portion 22 arranged on the lower side in the axial direction includes a shaft portion 22a extending along the axial direction and a disk portion 22b extending in the radial direction from the upper end of the shaft portion 22a.

The inner yoke 30 is made of a magnetic material and is fixed to both ends of a columnar core portion 31 extending in a direction orthogonal to the axial direction and both ends of the core portion 31, and faces each other with the rotation axis AX in between, that is, the rotation axis AX. The two facing portions 32 and 33 are provided symmetrically with respect to the center. As shown in FIG. 4, the two facing portions 32 and 33 are arranged side by side along the circumferential direction of the cylindrical outer yoke 50 in a plan view.

As shown in FIG. 3, the disk portion 21b of the upper first shaft portion 21 is fixed to the upper surfaces of the two opposing portions 32, 33, and the lower surface of the two opposing portions 32, 33 is lower. The disk portion 22b of the second shaft portion 22 is fixed. The two facing portions 32 and 33 have outer peripheral surfaces 32a and 33a having a shape along the circumferential direction. The outer peripheral surfaces 32a, 33a of the two opposing portions 32, 33 in the radial direction are formed as outer peripheral surfaces 32a, 33a forming a part of one circle in a plan view, respectively.

The exciting coil 41 as the magnetic field generating portion is wound around the central axis of the columnar core portion 31 (a virtual axis along the radial direction orthogonal to the rotation axis AX), and is wound from the two opposing portions 32 and 33. Is also arranged radially inside. Here, the exciting coil 41 is inside the two opposing portions 32, 33 in the vertical direction, that is, the exciting coil 41 is on both the upper side and the lower side of the two opposing portions 32, 33 in the vertical direction. Is preferably not extended. By arranging the exciting coil 41 in this way, the number of windings of the exciting coil 41 can be increased, and the generated magnetic field can be increased. Further, on the side where the core portion 31 and the exciting coil 41 are arranged, the facing portions 32 and 33 have a flat shape, but other surface shapes, for example, a curved surface that is convex inward or outward may be used. ..

An outer yoke 50 made of a magnetic material is arranged on the outer side of the inner yoke 30 as a rotor in the radial direction. The outer yoke 50 has a hollow cylindrical shape (cylindrical portion) centered on the rotation axis AX, and the inner peripheral surface 51 thereof has a gap with respect to the outer peripheral surfaces 32a and 33a of the two opposing portions 32 and 33, respectively. They are facing each other via S. The gap S is filled with a magnetic viscous fluid 70 as a magnetically responsive material.

Here, the magnetic viscous fluid 70 is a substance whose viscosity changes when a magnetic field is applied, and is, for example, a fluid in which particles (magnetic particles) made of a magnetic material are dispersed in a non-magnetic liquid (solvent). .. As the magnetic particles contained in the ferrofluid 70, for example, carbon-containing iron-based particles and ferrite particles are preferable. As the iron-based particles containing carbon, for example, the carbon content is preferably 0.15% or more. The diameter of the magnetic particles is preferably 0.5 μm or more, more preferably 1 μm or more. For the magnetic viscous fluid 70, it is desirable to select a solvent and magnetic particles so that the magnetic particles are less likely to precipitate due to gravity. Further, the ferrofluid 70 preferably contains a coupling material that prevents the precipitation of magnetic particles.

Fixing plates 61 and 62 made of non-magnetic material are fixed to the upper part and the lower part of the outer yoke 50, respectively. These fixing plates 61 and 62 are disks arranged around the rotation axis AX, and holes 61a and 62a penetrating in the axial direction (thickness direction) are formed at the centers thereof, respectively.

As shown in FIG. 3, the first fixing plate 61 is arranged so as to have a gap P1 between the first fixing plate 61 and the disk portion 21b of the first shaft portion 21, and the second fixing plate 62 is formed on the second shaft portion 22. It is arranged so as to have a gap P2 between it and the disk portion 22b. These gaps P1 and P2 are connected to the gap S, and the ferrofluid 70 in the gap S also flows into and is arranged in these gaps P1 and P2.

The shaft portion 21a of the first shaft portion 21 is inserted into the hole portion 61a of the upper first fixing plate 61, and the shaft portion of the second shaft portion 22 is inserted into the hole portion 62a of the lower second fixing plate 62. 22a is inserted. An O-ring 61b (O-ring) is arranged between the inner peripheral surface of the hole 61a and the outer peripheral surface of the shaft 21a, and between the inner peripheral surface of the hole 62a and the outer peripheral surface of the shaft 22a. An O-ring 62b (O-ring) is arranged.

The two O-rings 61b and 62b are ring members made of an elastic material. The O-ring 61b is in close contact with the inner peripheral surface of the hole 61a and the outer peripheral surface of the shaft portion 21a in a liquid-tight state, and the O-ring 62b is in close contact with the inner peripheral surface of the hole 62a and the outer peripheral surface of the shaft portion 22a. It adheres to the surface in a liquid-tight state.

By arranging the two O-rings 61b and 62b, it is possible to prevent the ferrofluid 70 in the gaps P1 and P2 from leaking to the outside of the torque generator 10, and the two shaft portions 21 and 22 have two. It is supported by two fixing plates 61 and 62, respectively. As a result, the outer yoke 50 and the inner yoke 30 can rotate relative to each other with the rotation axis AX (the central axis of the outer yoke 50 having a cylindrical portion) as the center of rotation.
An O-ring is provided between the disk portion 21b and the external yoke 50 or the first fixing plate 61, and between the disk portion 22b and the external yoke 50 or the second fixing plate 62, respectively. And, it is possible to limit the inflow of the ferrofluid 70 in the gap S into the gaps P1 and P2. Further, instead of the O-ring, a sealing member having excellent low torque sealing performance, for example, a V-ring (an annular member having a V-shaped cross section orthogonal to the circumferential direction) can be used.

The exciting coil 41 generates a magnetic field as a magnetic field generating unit by energizing from the control unit 40 (FIG. 1B). The control unit 40 controls the magnitude of the current applied to the exciting coil 41, thereby controlling the magnitude of the magnetic field generated by the exciting coil 41. The control unit 40 includes, for example, an energizing unit that energizes a coil, a central processing unit, and a storage device, and is supplied with electric power from a power source and executes a program stored in the storage device in the central processing unit. By performing control. Since the number of windings of the exciting coil 41 can be increased, the generated magnetic field can be increased.
In FIGS. 2 to 4, the wiring between the control unit 40 and the exciting coil 41 is omitted.

When a current is applied to the exciting coil 41, a magnetic field having magnetic field lines indicated by arrows in FIGS. 3 and 4 is generated. The magnetic lines of force reach the second facing portion 33 from the first facing portion 32 through the core portion 31, and flow from the second facing portion 33 to the outer yoke 50 facing the outer peripheral surface 33a. Further, a magnetic field line toward the first facing portion 32 is generated from the outer yoke 50 facing the outer peripheral surface 32a of the first facing portion 32. As a result, the magnetic field lines pass in the radial direction in the gap S.

Further, as shown in FIG. 4, the magnetic field lines directed from the second facing portion 33 toward the outer yoke 50 are the peripheral surfaces of the outer yoke 50 from the region 52 corresponding to the outer peripheral surface 33a of the second facing portion 33 in the outer yoke 50. It flows along the above and reaches the region 53 facing the outer peripheral surface 32a of the first facing portion 32. The magnetic field lines that reach this region 53 enter the first facing portion 32 and flow toward the core portion 31 side. In the torque generator 10, one magnetic circuit is formed by the magnetic field lines of such a path.
When the direction of energization of the exciting coil 41 is reversed, magnetic field lines opposite to those shown in FIGS. 3 and 4 are generated.

In the above configuration, when a current is applied to the exciting coil 41 to generate a magnetic field, a magnetic field along the radial direction is applied to the ferrofluid 70 in the gap S. Due to this magnetic field, the magnetic particles dispersed in the magnetic viscous fluid 70 gather along the magnetic field lines, and the magnetic particles arranged along the radial direction are magnetically connected to each other to form clusters. In this state, when a force is applied to rotate the two shaft portions 21, 22 or the outer yoke 50 in the direction centered on the rotation axis AX, a shearing force acts on the connected magnetic particles, and these magnetic particles act. Resistant force (torque) is generated. Therefore, the operator can feel the resistance as compared with the state where the magnetic field is not generated.

On the other hand, when the magnetic field generated by the exciting coil 41 is not generated, the magnetic particles are dispersed in the solvent in the ferrofluid 70. Therefore, when the operator operates any of the shaft portions 21, 22 and the external yoke 50, the operator rotates relatively without receiving a large resistance force.

In the torque generator 10 of the first embodiment, since the facing portions 32 and 33 are arranged so as to face each other over a wide range in the circumferential direction of the outer yoke 50, the outer peripheral surfaces 32a of the two facing portions 32 and 33, The gap S between the 33a and the outer yoke 50 can be widened in the circumferential direction. The two facing portions 32 and 33 have outer peripheral surfaces 32a and 33a having a shape along the circumferential direction. As a result, the distance between the outer yoke 50 and the inner peripheral surface 51 can be made uniform. Since the magnetic viscous fluid 70 in the gap S arranged in this way can be given magnetic lines along the radial direction, a substantially uniform resistance force (torque) is generated in a wide range in the circumferential direction. It is possible to obtain a large working torque as a whole.

<Second Embodiment>
FIG. 5A is a perspective view of the torque generator 110 according to the second embodiment as viewed from above, and FIG. 5B is a functional block diagram showing a control system of the torque generator 110. FIG. 6 is an exploded perspective view of the torque generator 110, and FIG. 7 is a cross-sectional view taken along the line BB'of FIG. 5 (a). FIG. 8A is a plan view showing the arrangement of the first rotor R11 and the outer yoke 160 in the torque generator 110, and FIG. 8B is a plan view showing the arrangement of the second rotor R12 and the outer yoke 160. FIG. 9 is a plan view showing the torque generator 110 excluding the first fixing plate 162 and the first shaft portion 121.

As shown in FIGS. 6 and 7, in the torque generator 110 according to the second embodiment, two shaft portions 121 and 122 arranged vertically are used, and two rotors R11 are used between the shaft portions. , R12 are arranged. In these rotors, a first rotor R11 having a first internal yoke 130 and a first exciting coil 151 (first coil) is arranged on the upper side in the axial direction, and a second internal yoke 140 is arranged on the lower side thereof. And a second rotor R12 provided with a second exciting coil 152 (second coil) are arranged. The external member arranged outside the two rotors R11 and R12 includes an external yoke 160 and a pair of fixing plates 162 and 163.

The two shaft portions 121 and 122 are made of a non-magnetic material and are integrated with each other in the axial direction of the rotating shaft AX via two rotors R11 and R12 arranged between them. The two shaft portions 121 and 122 can rotate around the rotation shaft AX together with the two rotors R11 and R12.

The first shaft portion 121 arranged on the upper side in the axial direction includes a shaft portion 121a extending along the axial direction and a disc portion 121b extending in the radial direction from the lower end of the shaft portion 121a. Similarly, the second shaft portion 122 arranged on the lower side in the axial direction includes a shaft portion 122a extending along the axial direction and a disc portion 122b extending in the radial direction from the upper end of the shaft portion 122a.

The first inner yoke 130 is made of a magnetic material and is fixed to both ends of a columnar first core portion 131 extending in a direction orthogonal to the axial direction and the first core portion 131, respectively, and faces each other with a rotation axis AX in between. It is provided with two facing portions 132 and 133. Similarly, the second inner yoke 140 is made of a magnetic material and is fixed to both ends of a columnar second core portion 141 extending in a direction orthogonal to the axial direction and a second core portion 141, respectively, and sandwiches the rotation axis AX. It is provided with two facing portions 142 and 143 facing each other. In the plane orthogonal to the rotation axis AX, the second core portion 141 is in a direction (second radial direction) orthogonal to the direction in which the first core portion 131 extends (first radial direction) with reference to the rotation axis AX. Extends in the radial direction).
Here, the first core portion 131 and the second core portion 141 can be arranged not orthogonal to each other as long as their extending directions intersect with each other.

As shown in FIG. 9, in a plan view, the facing directions of the two facing portions 132 and 133 of the first inner yoke 130 and the facing directions of the two facing portions 142 and 143 of the second inner yoke 140 are orthogonal to each other. ing. Then, along the circumferential direction of the cylindrical outer yoke 160, the facing portion 132 of the first inner yoke 130, the facing portion 142 of the second inner yoke 140, the facing portion 133 of the first inner yoke 130, and the second inner yoke 140. Opposing portions 143 of the above are sequentially arranged side by side so as to be separated from each other.
If the spaces between the opposing portions arranged side by side are filled with a non-magnetic material such as synthetic resin, the distance between the adjacent facing portions can be stabilized.

As shown in FIG. 6 or 7, the two opposing portions 132, 133 of the first inner yoke 130 and the two opposing portions 142, 143 of the second inner yoke 140 correspond to each other in the axially occupied range. As you can see, each is extended. Specifically, the upper surfaces of the two opposing portions 132 and 133 of the first inner yoke 130, the upper surfaces of the two opposing portions 142 and 143 of the second inner yoke 140, and the upper surface of the first exciting coil 151 are in the axial direction. The lower surfaces of the two opposing portions 132 and 133 of the first inner yoke 130, the lower surfaces of the two opposing portions 142 and 143 of the second inner yoke 140, and the lower surface of 152 are substantially the same position. , It is almost the same position in the axial direction.

The disc portion 121b of the upper first shaft portion 121 is fixed to the upper surfaces of the two opposing portions 132 and 133 of the first inner yoke 130 and the upper surfaces of the two opposing portions 142 and 143 of the second inner yoke 140. Has been done. Further, on the lower surfaces of the two opposing portions 132 and 133 of the first inner yoke 130 and the lower surfaces of the two opposing portions 142 and 143 of the second inner yoke 140, the disc portion of the lower second shaft portion 122 is formed. 122b is fixed.

Further, the upper and lower rotors R11 and R12 are integrated by, for example, fixing the first exciting coil 151 and the second exciting coil 152 to each other. In this case, it is preferable that the first exciting coil 151 and the second exciting coil 152 are fixed via an insulating material, for example, an insulating adhesive so as not to be electrically connected to each other.
On the other hand, the first exciting coil 151 and the second exciting coil 152 are not fixed to each other, but the two facing portions 132, 133 of the first rotor R11 and the two facing portions of the second rotor R12 are opposed to each other. The upper and lower surfaces of the portions 142 and 143 are raised and lowered by fixing the upper surfaces thereof to the lower surface of the disc portion 121b of the first shaft portion 121 and fixing the lower surface to the upper surface of the disc portion 122b of the second shaft portion 122. The rotors R11 and R12 can also be integrated.

The two facing portions 132 and 133 have outer peripheral surfaces 132a and 133a having a shape along the circumferential direction. The two facing portions 142 and 143 have outer peripheral surfaces 142a and 143a having a shape along the circumferential direction. As shown in FIG. 9, the radial outer peripheral surfaces 132a and 133a of the two opposing portions 132 and 133 of the first inner yoke 130 and the radial outer circumferences of the two opposing portions 142 and 143 of the second inner yoke 140. The surfaces 142a and 143a are each formed as peripheral surfaces forming a part of one circle in a plan view.

In the first rotor R11, the first exciting coil 151 as the magnetic field generating portion is wound around the central axis of the columnar first core portion 131 (a virtual axis along the radial direction orthogonal to the rotation axis AX). It is arranged radially inside the two facing portions 132 and 133. Also in the second rotor R12, the second exciting coil 152 as the magnetic field generating portion is wound around the central axis (the virtual axis along the radial direction orthogonal to the rotation axis AX) of the columnar second core portion 141. It is arranged radially inside the two facing portions 142 and 143. The central axes of the two core portions 131 and 141 are orthogonal to each other in a plane orthogonal to the direction along the rotation axis AX.

An outer yoke 160 made of a magnetic material is arranged on the outside of the two rotors R11 and R12. The outer yoke 160 has a hollow cylindrical shape (cylindrical portion) centered on the rotation axis AX, and its inner peripheral surface 161 is an outer peripheral surface 132a, 133a of the facing portions 132, 133 of the first inner yoke 130, and The second inner yoke 140 faces the outer peripheral surfaces 142a and 143a of the facing portions 142 and 143 via the gap S. The gap S is filled with the same magnetic viscous fluid 170 as in the first embodiment as a magnetically responsive material.

Fixing plates 162 and 163 made of non-magnetic material are fixed to the upper part and the lower part of the outer yoke 160, respectively. These fixing plates 162 and 163 are disks arranged around the rotation axis AX, and holes 162a and 163a penetrating in the axial direction (thickness direction) are formed at the centers thereof, respectively.

As shown in FIG. 7, the shaft portion 121a of the first shaft portion 121 is inserted into the hole portion 162a of the upper first fixing plate 162, and the hole portion 163a of the lower second fixing plate 163 is inserted into the shaft portion 121a. 2 The shaft portion 122a of the shaft portion 122 is inserted. As a result, the two shaft portions 121 and 122 are supported by the two fixing plates 162 and 163, respectively, so that the external yoke 160 and the two integrated rotors R11 and R12 are centered on the rotation shaft AX. , Relative rotation is possible.
Although not shown, an O-ring is arranged between the inner peripheral surface of the hole 162a and the outer peripheral surface of the shaft 121a as in the first embodiment, and the hole is provided. An O-ring is arranged between the inner peripheral surface of the 163a and the outer peripheral surface of the shaft portion 122a.

The two exciting coils 151 and 152 generate a magnetic field as a magnetic field generating unit when energized from the control unit 150 (FIG. 5B). The control unit 150 controls the magnitude of the current applied to the exciting coils 151 and 152, thereby controlling the magnitude of the magnetic field generated by the exciting coils 151 and 152, respectively. The control unit 150 includes, for example, an energizing unit that energizes the coil, a central processing unit, and a storage device, and is supplied with electric power from a power source and executes a program stored in the storage device in the central processing unit. By performing control.
Note that in FIGS. 6 to 9, the wiring between the control unit 150 and the two exciting coils 151 and 152 is omitted.

When a current is applied to the first exciting coil 151, a magnetic field having magnetic field lines indicated by arrows in FIGS. 8 (a) and 9 is generated. The lines of magnetic force reach the second facing portion 133 from the first facing portion 132 through the first core portion 131, and face the outer peripheral surface 133a from the outer peripheral surface 133a (one outer peripheral surface) of the second facing portion 133. It flows to the outer yoke 160 (first magnetic field line L1). Further, from the outer yoke 160 facing the outer peripheral surface 132a of the first facing portion 132, a magnetic field line (fourth magnetic field line L4) toward the outer peripheral surface 132a (the other outer peripheral surface) of the first facing portion 132 is generated. As a result, the magnetic field lines pass in the radial direction in the gap S between the two facing portions 132 and 133 and the outer yoke 160.

Further, when a current is applied to the second exciting coil 152, a magnetic field having magnetic field lines indicated by arrows in FIGS. 8 (b) and 9 is generated. The lines of magnetic force reach the second facing portion 143 from the first facing portion 142 through the second core portion 141, and face the outer peripheral surface 143a from the outer peripheral surface 143a (the other outer peripheral surface) of the second facing portion 143. It flows to the outer yoke 160 (third magnetic field line L3). Further, from the outer yoke 160 facing the outer peripheral surface 142a of the first facing portion 142, a magnetic field line toward the outer peripheral surface 142a (one outer peripheral surface) of the first facing portion 142 is generated (second magnetic field line L2). As a result, the magnetic field lines pass in the radial direction in the gap S between the two facing portions 142 and 143 and the outer yoke 160.

Further, as shown in FIG. 9, the magnetic field lines (first magnetic field lines L1) directed from the second facing portion 133 of the first rotor R11 toward the outer yoke 160 are used as the first external magnetic field lines L11 and are second in the outer yoke 160. From the region 164 corresponding to the outer peripheral surface 133a of the facing portion 133, it flows along the peripheral surface of the outer yoke 160 and reaches the region 165 facing the outer peripheral surface 142a of the first facing portion 142 of the second rotor R12. The magnetic field lines that reach this region 165 enter the first facing portion 142 of the second rotor R12 as the second magnetic field lines L2 and flow toward the second core portion 141 side.

Subsequently, the magnetic field lines flowing through the second core portion 141 are directed from the second opposing portion 143 of the second rotor R12 to the outer yoke 160 (third magnetic field line L3). Further, in the outer yoke 160, it flows from the region 166 corresponding to the outer peripheral surface 143a of the second facing portion 143 along the peripheral surface of the outer yoke 160 and faces the outer peripheral surface 132a of the first facing portion 132 of the first rotor R11. It reaches the region 167 (second external magnetic field line L12). The magnetic field lines that reach this region 167 enter the first facing portion 132 of the first rotor R11 and flow toward the first core portion 131 (fourth magnetic field line L4).

In the torque generator 110, the first magnetic line L1, the first external magnetic line L11, the second magnetic line L2, the third magnetic line L3, the second external magnetic line L12, and the fourth magnetic line L4 are continuous in this order. In this way, one magnetic circuit is formed by the magnetic field lines of the path flowing between the two rotors R11 and R12 via the outer yoke 160.
If the energizing directions of the exciting coils 151 and 152 are reversed from those in the above example, magnetic field lines opposite to those shown in FIGS. 8 and 9 are generated. Further, when filling the space between the opposing portions arranged side by side along the circumferential direction with a non-magnetic material such as synthetic resin, the distance between the adjacent facing portions is set so that the external magnetic field lines L11 and L12 are formed. .. By filling with a non-magnetic material, the distance between adjacent facing portions becomes constant, so that a magnetic circuit having stable characteristics can be realized.

In the above configuration, when a current is applied to the exciting coils 151 and 152 to generate a magnetic field, a magnetic field along the radial direction is applied to the ferrofluid 170 in the gap S. Due to this magnetic field, the magnetic particles dispersed in the magnetic viscous fluid 170 are gathered along the magnetic field lines, and the magnetic particles arranged along the radial direction are magnetically connected to each other to form clusters. In this state, when a force is applied to rotate the two shaft portions 121, 122 or the outer yoke 160 in the direction centered on the rotation axis AX, a shearing force acts on the connected magnetic particles, and these magnetic particles act. Resistant force (torque) is generated. Therefore, the operator can feel the resistance as compared with the state where the magnetic field is not generated.

On the other hand, when the magnetic fields generated by the two exciting coils 151 and 152 are not generated, the magnetic particles are dispersed in the solvent in the ferrofluid 170. Therefore, when the operator operates any of the shaft portions 121 and 122 and the external yoke 160, the operator rotates relatively without receiving a large resistance force. Alternatively, when the exciting coils 151 and 152 are not energized and there is a residual magnetic flux in the yoke, the resistance torque remains according to the density of the residual magnetic flux.

In the torque generator 110 of the second embodiment, the facing portions 132, 133 of the first rotor R11 and the facing portions 142, 143 of the second rotor R12 are arranged over a wide range in the circumferential direction of the outer yoke 160. , The gap S between these opposing portions 132, 133, 142, 143 and the outer yoke 160 can be widened in the circumferential direction. Since the magnetic viscous fluid 170 in the gap S arranged in this way can be given magnetic lines along the radial direction, a substantially uniform resistance force (torque) is generated in a wide range in the circumferential direction. It is possible to obtain a large working torque as a whole.

Further, since the first rotor R11 and the second rotor R12 are arranged at different positions in the axial direction, the internal space of the outer yoke 160 can be effectively utilized, and a magnetic circuit as shown in FIG. 9 is formed. By doing so, the magnetic field can be expanded in the axial direction. Therefore, the working surface of the ferrofluid 170 can be enlarged, and the control range of the resistance force (torque) given to the operator can be widened.
The other configurations, actions, and effects are the same as those in the first embodiment.

<Third Embodiment>
FIG. 10A is a perspective view of the torque generator 210 according to the third embodiment as viewed from above, and FIG. 10B is a functional block diagram showing a control system of the torque generator 210. FIG. 11 is an exploded perspective view of the torque generator 210, and FIG. 12 is a cross-sectional view taken along the line CC'of FIG. 10 (a). FIG. 13 is a cross-sectional view taken along the line DD'of FIG.

As shown in FIG. 11, in the torque generator 210 according to the third embodiment, an internal yoke 220 having two yokes 222 and 223 arranged vertically and an exciting coil 231 arranged in the internal yoke 220 A rotor is provided. The external member arranged on the outside of the rotor includes an external yoke 240 and a pair of fixing plates 251 and 252.

As shown in FIG. 11, the inner yoke 220 is made of a magnetic material and has a columnar core portion 221 extending in the axial direction, an upper yoke 222 fixed above the core portion 221 in the axial direction, and a core portion. It includes a lower yoke 223 fixed to the lower side in the axial direction of 221. Both ends of the core portion 221 in the axial direction are connected to the upper wall portion 222a (connecting portion) of the upper yoke 222 and the bottom wall portion 223a (connecting portion) of the lower yoke 223, respectively.

The upper yoke 222 includes a plate-shaped upper wall portion 222a, a first facing portion 222b extending downward in the axial direction from a part of the outer circumference of the upper wall portion 222a, and a shaft extending upward from the center of the upper wall portion 222a in a plan view. The unit 222c is provided. The upper wall portion 222a is arranged so that its central axis is located on the rotation axis AX, and its upper surface is orthogonal to the axial direction. The shaft portion 222c extends along the axial direction.
Here, the upper wall portion 222a and the bottom wall portion 223a are formed into a plate shape, but the connecting portion is not limited to this, and for example, a curved surface that is convex upward or downward, or a flat surface. The shape can be any shape.

The lower yoke 223 extends downward from the center of the disc-shaped bottom wall portion 223a, the second facing portion 223b extending axially upward from a part of the outer circumference of the bottom wall portion 223a, and the bottom wall portion 223a in a plan view. It is provided with a shaft portion 223c (FIG. 12). The bottom wall portion 223a is arranged so that its central axis is located on the rotation axis AX, and its bottom surface is orthogonal to the axial direction. The shaft portion 223c extends along the axial direction.
The upper and lower yokes 222 and 223 each have one facing portion, but each of the upper and lower yokes 222 and 223 may have a plurality of facing portions and are arranged alternately in the circumferential direction in a comb-teeth shape.

As shown in FIG. 12, the first facing portion 222b of the upper yoke 222 includes an outer peripheral surface 222s facing the inner peripheral surface 241 of the outer yoke 240, while the inner peripheral surface 222t is directed outward as it goes downward. It is inclined to. Therefore, the thickness of the first facing portion 222b becomes smaller toward the lower side.

The second facing portion 223b of the lower yoke 223 includes an outer peripheral surface 223s facing the inner peripheral surface 241 of the outer yoke 240, while the inner peripheral surface 223t is inclined toward the outside toward the upper side. Therefore, the thickness of the second facing portion 223b becomes smaller toward the upper side.

The first facing portion 222b of the upper yoke 222 and the second facing portion 223b of the lower yoke 223 face each other with the rotation axis AX interposed therebetween, and as shown in FIG. 13, they are cylindrical in a plan view. They are arranged side by side along the circumferential direction of the outer yoke 240.

The exciting coil 231 as the magnetic field generating portion is wound around the central axis (virtual axis along the rotation axis AX) of the columnar core portion 221 and is arranged radially inside the upper and lower yokes 222 and 223. Has been done.

An outer yoke 240 made of a magnetic material is arranged outside the inner yoke 220 as a rotor in the radial direction. The outer yoke 240 has a hollow cylindrical shape (cylindrical portion) centered on the rotation axis AX, and its inner peripheral surface 241 is an outer peripheral surface 222s of the first facing portion 222b and an outer peripheral surface of the second facing portion 223b. It faces 223s via a gap S. The gap S is filled with the same magnetic viscous fluid 270 as in the first embodiment as a magnetically responsive material. The two facing portions 222b and 223b have outer peripheral surfaces 222s and 223s having a shape along the circumferential direction.

Fixing plates 251 and 252 made of non-magnetic material are fixed to the upper part and the lower part of the outer yoke 240, respectively. These fixing plates 251 and 252 are disks arranged around the rotation axis AX, and holes 251a and 252a penetrating in the axial direction (thickness direction) are formed at the centers thereof, respectively.

As shown in FIG. 12, the first fixing plate 251 is arranged so as to have a gap P21 with the upper wall portion 222a of the upper yoke 222, and the second fixing plate 252 is the bottom wall portion of the lower yoke 223. It is arranged so as to have a gap P22 between it and 223a. These gaps P21 and P22 are connected to the gap S, and the ferrofluid 270 in the gap S also flows into and is arranged in these gaps P21 and P22.

As shown in FIG. 12, the shaft portion 222c is inserted into the hole portion 251a of the upper first fixing plate 251, and the shaft portion 223c is inserted into the hole portion 252a of the lower second fixing plate 252. An O-ring 251b (O-ring) is arranged between the inner peripheral surface of the hole 251a and the outer peripheral surface of the shaft 222c, and between the inner peripheral surface of the hole 252a and the outer peripheral surface of the shaft 223c. An O-ring 252b (O-ring) is arranged.

The two O-rings 251b and 252b are ring members made of an elastic material. The O-ring 251b is in close contact with the inner peripheral surface of the hole 251a and the outer peripheral surface of the shaft portion 222c in a liquid-tight state, and the O-ring 252b is in close contact with the inner peripheral surface of the hole portion 252a and the outer peripheral surface of the shaft portion 223c. It adheres to the surface in a liquid-tight state.

By arranging the two O-rings 251b and 252b, it is possible to prevent the ferrofluid 270 in the gaps P21 and P22 from leaking to the outside of the torque generator 210, and the two shaft portions 222c and 223c are two. By being supported by the two fixing plates 251 and 252, respectively, the outer yoke 240 and the inner yoke 220 can rotate relative to each other about the rotation axis AX.
An O-ring is provided between the upper wall portion 222a and the outer yoke 240 or the first fixing plate 251 and between the bottom wall portion 223a and the outer yoke 240 or the second fixing plate 252, respectively. And, it is possible to limit the inflow of the ferrofluid 270 in the gap S into the gaps P21 and P22. Further, instead of the O-ring, a sealing member having excellent low torque sealing performance, for example, a V-ring (an annular member having a V-shaped cross section orthogonal to the circumferential direction) can be used.

The exciting coil 231 generates a magnetic field as a magnetic field generating unit by energizing from the control unit 230 (FIG. 10B). Similar to the control unit 40 of the first embodiment, the control unit 230 controls the magnitude of the current applied to the exciting coil 231 and thereby controls the magnitude of the magnetic field generated by the exciting coil 231.
Note that in FIGS. 11 to 13, the wiring between the control unit 230 and the exciting coil 231 is omitted.

When a current is applied to the exciting coil 231, a magnetic field having magnetic field lines indicated by arrows in FIGS. 12 and 13 is generated. The lines of magnetic force pass from the upper wall portion 222a of the upper yoke 222 through the core portion 221 to reach the bottom wall portion 223a of the lower yoke 223, flow from the bottom wall portion 223a to the second facing portion 223b, and flow from the bottom wall portion 223a to the second facing portion 223b. It flows to the outer yoke 240 facing the. Further, from the outer yoke 240 facing the outer peripheral surface 222s of the first facing portion 222b of the upper yoke 222, a magnetic field line toward the first facing portion 222b is generated, and this magnetic field line flows to the upper wall portion 222a and reaches the core portion 221. .. In this flow, magnetic lines of force pass in the radial direction in the gap S.

Further, as shown in FIG. 13, the lines of magnetic force directed from the second facing portion 223b toward the outer yoke 240 are from the region 242 corresponding to the outer peripheral surface 223s of the second facing portion 223b in the outer yoke 240 to the peripheral surface of the outer yoke 240. It flows along the above and reaches the region 243 facing the outer peripheral surface 222s of the first facing portion 222b. The magnetic field lines that reach this region 243 enter the first facing portion 222b and flow toward the core portion 221 side. In the torque generator 210, one magnetic circuit is formed by the magnetic field lines of such a path.
When the direction of energization of the exciting coil 231 is reversed, magnetic field lines opposite to those shown in FIGS. 12 and 13 are generated.

In the above configuration, when a current is applied to the exciting coil 231 to generate a magnetic field, a magnetic field along the radial direction is applied to the ferrofluid 270 in the gap S. Due to this magnetic field, the magnetic particles dispersed in the magnetic viscous fluid 270 gather along the magnetic field lines, and the magnetic particles arranged along the radial direction are magnetically connected to each other to form clusters. In this state, when a force is applied to rotate the two shaft portions 222c, 223c or the outer yoke 240 in the direction centered on the rotation axis AX, a shearing force acts on the connected magnetic particles, and these magnetic particles act. Resistant force (torque) is generated. Therefore, the operator can feel the resistance as compared with the state where the magnetic field is not generated.

On the other hand, when the magnetic field generated by the exciting coil 231 is not generated, the magnetic particles are dispersed in the solvent in the ferrofluid 270. Therefore, when the operator operates any of the shaft portions 222c, 223c, and the external yoke 240, they rotate relatively without receiving a large resistance force. Alternatively, when the exciting coil 231 is not energized and there is a residual magnetic flux in the yoke, the resistance torque remains according to the density of the residual magnetic flux.

In the torque generator 210 of the third embodiment, the core portion 221 is arranged so as to extend in the axial direction, and the exciting coil 231 is wound around the central axis of the core portion 221 in the radial direction. The degree of freedom in design can be increased.
The other configurations, actions, and effects are the same as those in the first embodiment or the second embodiment.
Although the present invention has been described with reference to the above-described embodiment, the present invention is not limited to the above-described embodiment, and can be improved or modified within the purpose of improvement or the idea of the present invention.

As described above, since the torque generator according to the present invention can form a magnetic circuit through which magnetic lines of force pass through a wider region, the magnetic field acting on the ferrofluid in the radial direction of the cylindrical rotating body is wide. It is useful in that it can be made substantially uniform in the range, which makes it possible to increase the resistance (torque) of the ferrofluid to the rotating body.

10 Torque generator 21 1st shaft part 21a Shaft part 21b Disc part 22 2nd shaft part 22a Shaft part 22b Disk part 30 Internal yoke 31 Core part 32 1st facing part 32a Outer peripheral surface 33 2nd facing part 33a Outer peripheral surface 40 Control unit 41 Exciting coil 50 External yoke 51 Inner peripheral surface 52, 53 Area 61 1st fixing plate 62 2nd fixing plate 61a, 62a Holes 61b, 62b O-ring
110 Torque generator 121 1st shaft part 121a Shaft part 121b Disc part 122 2nd shaft part 122a Shaft part 122b Disc part 130 1st internal yoke 131 1st core part 132 1st facing part 132a Outer peripheral surface 133 2nd facing Part 133a Outer surface 140 Second inner yoke 141 Second core part 142 First facing part 142a Outer surface 143 Second facing part 143a Outer surface 150 Control part 151 First exciting coil (first coil)
152 Second excitation coil (second coil)
160 Outer yoke 161 Inner peripheral surface 162 First fixing plate 162a Hole 163 Second fixing plate 163a Hole 164, 165, 166, 167 Area 210 Torque generator 220 Inner yoke 221 Core part 222 Upper yoke 222a Upper wall part 222b 1 Opposing part 222c Shaft part 222s Outer peripheral surface 222t Inner peripheral surface 223 Lower yoke 223a Bottom wall part 223b Second facing part 223c Shaft part 223s Outer peripheral surface 223t Inner peripheral surface 230 Control part 231 Excitation coil 240 External yoke 241 Inner peripheral surface 242 243 Area 251 First fixing plate 251a Hole 251b O-ring (O-ring)
252 Second fixing plate 252a Hole 252b O-ring (O-ring)
70, 170, 270 Ferrofluid (magnetically responsive material)
P1, P2, P21, P22 Gap R11 1st rotor R12 2nd rotor S Gap AX Rotation axis L1 1st magnetic line L2 2nd magnetic line L3 3rd magnetic line L4 4th magnetic line L11 1st external magnetic line L12 2nd External magnetic field lines

Claims (7)

A torque generator including an outer yoke having a cylindrical portion and an inner yoke arranged inside the cylindrical portion.
The inner yoke includes a plurality of facing portions having an outer peripheral surface facing the inner peripheral surface of the cylindrical portion, and is arranged so as to be rotatable relative to the outer yoke with the central axis of the cylindrical portion as the rotation center.
The gap between the outer peripheral surface of each of the plurality of facing portions and the inner peripheral surface of the outer yoke facing each other is filled with a ferrofluid.
A magnetic field generating portion is arranged inside the plurality of facing portions of the internal yoke.
The magnetic field generating unit is controlled by a control unit, and has a magnetic field line from one of the outer peripheral surfaces of the plurality of facing portions of the inner yoke toward the inner peripheral surface of the outer yoke facing the inner peripheral surface of the outer yoke and the inner circumference of the outer yoke. A magnetic field is generated to form a magnetic circuit that includes a magnetic field line from the surface to the other outer peripheral surface of the plurality of opposing portions of the internal yoke.
A torque generator characterized in that the plurality of facing portions are arranged side by side along the circumferential direction of the cylindrical portion. The internal yoke includes a core portion extending along the radial direction of the cylindrical portion so as to connect two facing portions symmetrically arranged about the central axis of the plurality of facing portions.
The torque generating device according to claim 1, wherein the magnetic field generating unit is a coil wound around the core unit with the radial direction as a virtual axis, and the coil is energized by the control unit. The internal yoke includes at least a first internal yoke and a second internal yoke.
The first inner yoke is formed along the first radial direction of the cylindrical portion so as to connect the two first facing portions symmetrically arranged about the central axis and the two first facing portions. A first core portion extending and a first coil wound around the first core portion with the first radial direction as a virtual axis are provided.
The second inner yoke is formed along the second radial direction of the cylindrical portion so as to connect the two second facing portions symmetrically arranged about the central axis and the two second facing portions. A second core portion extending and a second coil wound around the second core portion with the second radial direction as a virtual axis are provided.
The second radial direction is a direction that intersects the first radial direction with respect to the central axis.
The two first facing portions and the two second facing portions are alternately arranged side by side along the circumferential direction.
The torque generator according to claim 2, wherein the first core portion and the second core portion are arranged at different positions in the central axis direction of the cylindrical portion. The magnetic field generating part is
A first line of magnetic force passing through the first core portion and heading from the outer peripheral surface of one of the two first opposing portions of the first inner yoke to the inner peripheral surface of the outer yoke facing the first inner yoke.
A first external magnetic field line that passes through the external yoke in the circumferential direction in succession to the first magnetic field line,
A second line of magnetic force from the inner peripheral surface of the outer yoke to the outer peripheral surface of one of the two second opposing portions of the second inner yoke.
The inner circumference of the outer yoke that passes through the second core portion in succession to the second magnetic field line and faces the outer peripheral surface of the other of the two second opposing portions of the second inner yoke. The third line of magnetic force toward the surface,
In the outer yoke, a second external magnetic field line that passes through the outer yoke in the circumferential direction is continuous with the third magnetic field line.
A fourth magnetic field line extending from the inner peripheral surface of the outer yoke to the outer peripheral surface of the other of the two opposing portions of the first inner yoke and reaching the first core portion.
The torque generator according to claim 3, wherein a magnetic field for forming one magnetic circuit including the above is generated. The internal yoke includes a core portion extending along the central axis direction of the cylindrical portion.
The torque generating device according to claim 1, wherein the magnetic field generating unit is a coil wound around the core unit with the central axis direction as a virtual axis, and the coil is energized by the control unit. .. The internal yoke includes a connecting portion that is connected to each of the plurality of facing portions and extends in the radial direction.
Both ends of the core portion in the central axis direction are connected to the connecting portion, respectively.
The magnetic field generating part is
Passing through the core portion in the central axis direction, passing through one of the connecting portions, from the outer peripheral surface of one of the plurality of opposing portions of the inner yoke to the inner peripheral surface of the outer yoke facing the inner yoke. The first line of magnetic force going to
From the inner peripheral surface of the outer yoke to another one of the outer peripheral surfaces of the plurality of opposing portions of the inner yoke, the core portion is directed in the central axial direction through the other one of the connecting portions. The second line of magnetic force leading to
The torque generator according to claim 5, wherein a magnetic field for forming one magnetic circuit including the above is generated. The torque generating device according to any one of claims 1 to 6, wherein the plurality of facing portions have an outer peripheral surface having a shape along the circumferential direction.