JP5656902B2 - Actuator - Google Patents

Description

  The present invention relates to an actuator that moves and positions a movable part by electromagnetic force.

  An actuator (electromagnetic actuator) is one of devices for positioning a movable part by levitation with electromagnetic force. In this actuator, for example, a beam condensing lens of a laser beam machine or an electrode of an electric discharge machine is used as a movable part, and the movable part is lifted by electromagnetic force to perform positioning.

  There is a 6-degree-of-freedom actuator that drives and controls 6 degrees of freedom of XYZ translation and rotation around XYZ. For example, the 6-degree-of-freedom actuator described in Patent Document 1 floats the movable part in a non-contact manner by the attractive force of an electromagnet, thereby positioning the movable part in the Z direction.

JP-A-6-273285 (paragraph numbers “0053” to “0070”, FIGS. 14 to 18)

  However, in the above-described conventional technique, the superconducting magnetic levitation characteristic test apparatus has a problem that the Z-direction stroke cannot be increased because the Z-direction positioning is performed with the movable part held by the electromagnet. Further, since the magnetic circuits in the Z direction and the XY direction are separated, there is a problem that the overall size of the apparatus becomes large.

  The present invention has been made in view of the above, and an object of the present invention is to obtain an actuator having a small configuration capable of positioning with a large stroke.

In order to solve the above-described problems and achieve the object, the present invention provides a first radial voice coil in which the first plane is a winding plane and a second plane perpendicular to the first plane is a winding plane. A first voice coil stator having a first thrust voice coil, a first magnetic flux passing through the first radial voice coil and the first thrust voice coil, and the first a first permanent magnet armature which is moved by the second coil current flows in and the first thrust voice coil first coil current is applied to the radial voice coil, the first and second A second voice coil having a second radial voice coil whose third plane perpendicular to the plane is a winding plane and a second thrust voice coil whose second plane is a winding plane And stator, with generating a second magnetic flux penetrating said second radial voice coil and said second thrust voice coil, and that the said second third coil current flows in the second radial voice coil A second permanent magnet mover that is moved by passing a fourth coil current through two thrust voice coils, and an actuator mover that is positioned by the movement of the first and second permanent magnet movers. And the first permanent magnet mover is moved by a Lorentz force generated by the first magnetic flux and the first and second coil currents, and the second permanent magnet mover is It is driven by the Lorentz force generated by the magnetic flux and the third and fourth coil current of the actuator movable element, the first And the rotation angle and 6 degrees of freedom in the three directions of translational displacement of the second three-axis direction by the movement of the permanent magnet armature, characterized in that the driven and controlled.

  According to the present invention, it is possible to obtain a large positioning stroke with a small actuator. In addition, there is an effect that the movable part that can be moved by the actuator can be made small.

FIG. 1 is a perspective view including a partial perspective view showing the actuator according to the embodiment. FIG. 2 is a diagram illustrating a configuration of a permanent magnet mover and a voice coil stator of the actuator according to the embodiment. FIG. 3 is a diagram for explaining the shape of the radial voice coil. FIG. 4 is a diagram for explaining the shape of the thrust voice coil. FIG. 5 is a diagram for explaining the magnetic pole property and magnetic path of the permanent magnet mover. FIG. 6 is a diagram for explaining the arrangement positions of the sensors included in the actuator according to the embodiment.

  Hereinafter, an actuator according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

Embodiment.
FIG. 1 is a perspective view including a partial perspective view showing the actuator according to the embodiment. The actuator 100 of this embodiment is a six-degree-of-freedom actuator that drives and controls all six degrees of freedom of XYZ translation and rotation around XYZ (three axial rotation angles and three-direction translational displacement) with the Lorentz force of the voice coil. .

  The actuator 100 positions a movable part (a driven body such as a beam condensing lens or an electrode) by electromagnetic force so as to position a beam condensing lens of a laser processing machine or an electrode of an electric discharge machine. . The actuator 100 has a structure in which another part can be attached to the center of the actuator 100 by providing a magnetic circuit on the outer periphery of the actuator 100.

  The actuator 100 includes an actuator mover 1, permanent magnet movers 2a to 2d, voice coil stators 3a to 3d, a base plate 4, and sensors 7a to 7f. In FIG. 1, the sensors 7a, 7c, and 7d are illustrated, and the sensors 7b, 7e, and 7f are not illustrated.

  The actuator mover 1 is joined to the permanent magnet movers 2a to 2d, and is positioned by the movement of the permanent magnet movers 2a to 2d. The actuator movable element 1 holds movable parts such as a beam condensing lens (not shown) and electrodes (not shown) at the center thereof. The actuator movable element 1 here is a substantially flat plate-like member, and is provided with, for example, a disk-shaped space for disposing a movable portion at the center thereof. FIG. 1 illustrates a case where the actuator movable element 1 is arranged so that the main surface of the actuator movable element 1 is substantially parallel to the XY plane.

  A movable part such as a beam condensing lens performs XYZ translation and rotation around XYZ while being fixed to the actuator movable element 1. The XYZ translation is a position movement in the X direction, a position movement in the Y direction, and a position movement in the Z direction. Rotation around XYZ includes rotational movement with the X axis as the rotational axis (rotational angle θ), rotational movement with the Y axis as the rotational axis (rotational angle φ), and rotational movement with the Z axis as the rotational axis (rotational angle ψ). It is.

  The voice coil stators 3a to 3d generate translational force and rotational force in the permanent magnet movers 2a to 2d, respectively. Each of the voice coil stators 3a to 3d has a plurality of thrust voice coils and a plurality of radial voice coils. The thrust voice coil is a thrust direction driving voice coil, and the radial voice coil is a radial direction driving voice coil.

  The voice coil stators 3a and 3c are disposed on the end side in the + X direction and the end side in the −X direction of the actuator mover 1, respectively. The voice coil stators 3b and 3d are disposed on the end side in the −Y direction and the end side in the + Y direction of the actuator mover 1, respectively.

  The permanent magnet movers 2 a to 2 d have a substantially flat plate shape and are vertically coupled to the actuator mover 1. The permanent magnet movers 2a and 2c are arranged so that the main surfaces are substantially parallel to the YZ plane, and the permanent magnet movers 2b and 2d are arranged so that the main surfaces are substantially parallel to the ZX plane. Has been.

  The permanent magnet movers 2a and 2c are joined to the actuator mover 1 on the end side in the + X direction and the end side in the −X direction of the actuator mover 1, respectively. The permanent magnet movers 2b and 2d are joined to the actuator mover 1 on the end side in the −Y direction and the end side in the + Y direction of the actuator mover 1, respectively.

  The permanent magnet movers 2a to 2d are disposed so as to pass through the plurality of thrust voice coils included in the voice coil stators 3a to 3d and to be sandwiched between the plurality of radial voice coils.

  As described above, the permanent magnet movers 2a to 2d and the voice coil stators 3a to 3d according to the present embodiment are arranged on the outer peripheral portion of the actuator mover 1, and the central portion of the actuator mover 1 is opened. ing. The base plate 4 holds the voice coil stators 3a to 3d in a fixed state.

  The sensors 7a to 7f detect gaps between the sensors 7a to 7f and the actuator movable element 1. The actuator 100 is connected to a control device (not shown) that controls the amount and direction of current flowing through the permanent magnet movers 2a to 2d. The control device calculates the XYZ translation and rotation around the XYZ of the movable part based on the gaps detected by the sensors 7a to 7f, and performs feedback control to the permanent magnet movers 2a to 2d using the calculation result.

  Specifically, the control device calculates the amount of movement in the XYZ direction and the amount of rotation about the XYZ axis necessary to move the movable part to the desired position based on the calculated XYZ translation and rotation about the XYZ. A current corresponding to the calculation result is supplied to the voice coil stators 3a and 3c.

  Next, the configuration of the permanent magnet movers 2a to 2d and the voice coil stators 3a to 3d, which are components of the actuator 100 shown in FIG. 1, will be described. FIG. 2 is a diagram illustrating a configuration of a permanent magnet mover and a voice coil stator of the actuator according to the embodiment. 3 is a diagram for explaining the shape of the radial voice coil, and FIG. 4 is a diagram for explaining the shape of the thrust voice coil.

  Since the permanent magnet movers 2a to 2d, which are constituent elements of the actuator 100 shown in FIG. 1, all have the same configuration, the configuration of the permanent magnet mover 2b will be described here. Since the voice coil stators 3a to 3d, which are constituent elements of the actuator 100 shown in FIG. 1, all have the same configuration, the configuration of the voice coil stator 3b will be described here.

  FIG. 2 shows a front view of the voice coil stator 3b and an AA sectional view of the voice coil stator 3b. 3 shows a perspective view of the voice coil stator 3b when the voice coil stator 3b of FIG. 2 is cut along an AA line. FIG. 4 shows a part of the voice coil stator 3b as a perspective view and a perspective view.

  The voice coil stator 3b includes radial voice coils 5b, 6b, 8b, and 9b. The permanent magnet movable element 2b includes thrust voice coils 10b, 11b, and 12b.

  The winding planes of the radial voice coils 5b, 6b, 8b, 9b are all ZX planes, and the winding planes of the thrust voice coils 10b, 11b, 12b are all XY planes. Thereby, the winding planes of the radial voice coils 5b, 6b, 8b, and 9b and the winding planes of the thrust voice coils 10b, 11b, and 12b are orthogonal to each other.

  In the voice coil stator 3b, a radial voice coil 5b is disposed above the radial voice coil 6b, and a radial voice coil 8b is disposed above the radial voice coil 9b.

  In the voice coil stator 3b, radial voice coils 5b and 8b are arranged on the upper side of the voice coil stator 3b so as to face each other with the permanent magnet movable element 2b interposed therebetween. Similarly, in the voice coil stator 3b, radial voice coils 6b and 9b are disposed on the lower side of the voice coil stator 3b so as to face each other with the permanent magnet movable element 2b interposed therebetween. The radial voice coils 5b, 6b, 8b, and 9b generate a thrust in the Y direction on the permanent magnet movable element 2b.

  The radial voice coils 5b, 6b, 8b and 9b have a square shape (rectangular ring shape) when viewed from the Y direction. Specifically, the radial voice coils 5b, 6b, 8b, and 9b are pillars (rectangular annular pillars) having a square-shaped top and bottom surfaces. In other words, the radial voice coils 5b, 6b, 8b, 9b are joined such that four columnar bodies are arranged in a square shape. As described above, the radial voice coils 5b, 6b, 8b, and 9b have a substantially cylindrical shape having a predetermined height (the height of the columnar body).

  Further, in the voice coil stator 3b, the thrust voice coils 10b, 11b, and 12b are arranged so that the permanent magnet movable element 2b penetrates the inner side (inner ring portion) of the square shape of the thrust voice coils 10b, 11b, and 12b. Has been. Thereby, the thrust voice coils 10b, 11b, and 12b are arranged in the voice coil stator 3b so that the respective main surfaces of the square shape are parallel to the XY plane.

  The thrust voice coils 10b, 11b, and 12b have the same shape as the radial voice coils 5b, 6b, 8b, and 9b. The thrust voice coils 10b, 11b, and 12b generate a thrust in the Z direction on the permanent magnet movable element 2b.

  In the voice coil stator 3b, the permanent magnet movable element 2b is disposed in the ZX plane, and the thrust voice coils 10b, 11b, and 12b are disposed in the XY plane so as to surround the permanent magnet movable element 2b.

  FIG. 4 shows the positional relationship between the radial voice coils 5b and 8b and the thrust voice coil 10b. Of the four columnar portions of the thrust voice coil 10b, one columnar portion extending in the X direction is surrounded by the inner wall surface (inner ring portion) of the radial voice coil 5b, and the other columnar portion is the radial voice coil. Radial voice coils 5b and 8b are arranged so as to be surrounded by the inner wall surface of 8b.

  Similarly, of the four columnar portions of the thrust voice coil 12b, one columnar portion extending in the X direction is surrounded by the inner wall surface of the radial voice coil 6b, and the other columnar portion is the radial voice coil 9b. Radial voice coils 6b and 9b are arranged so as to be surrounded by the inner wall surface.

  In other words, the thrust voice coil 10b is disposed so as to pass through the inner ring portions of the radial voice coils 5b, 8b, and the thrust voice coil 12b is disposed so as to pass through the inner ring portions of the radial voice coils 6b, 9b. ing.

  Of the four columnar portions of the thrust voice coil 11b, one columnar portion extending in the X direction is sandwiched between the outer wall surfaces (outer ring portions) of the radial voice coils 5b and 6b, and the other columnar portion. Are placed between the outer wall surfaces of the radial voice coils 8b, 9b. The radial voice coils 5b, 6b, 8b, 9b are arranged.

  The permanent magnet mover 2b includes a permanent magnet segment that generates radial thrust, a permanent magnet segment that generates thrust thrust, and a magnetic member that passes magnetic flux. In the permanent magnet mover 2b, these are integrated. Molded.

  Permanent magnet segments that generate radial thrust are arranged between the radial voice coils 5b and 8b and between the radial voice coils 6b and 9b. The magnetic member is sandwiched between permanent magnet segments that generate a thrust thrust. Of the permanent magnet mover 2b, the portion composed of the permanent magnet segment that generates thrust thrust and the magnetic member is disposed so as to be surrounded between the thrust voice coils 10b, between the thrust voice coils 11b, and between the thrust voice coils 12b. .

  A current (coil current) flows through the voice coil stator 3b in the direction D1 that is the + X direction or the direction D2 that is the -X direction. For example, a current in the direction D1 flows through the upper columnar portion of the radial voice coil 5b. Thereby, the electric current of the direction D2 flows into the columnar part below the radial voice coil 5b. In other words, when the radial voice coil 5b is viewed from the -Y direction toward the + Y direction, a current flows counterclockwise in the ZX plane to the radial voice coil 5b.

  Similarly, in the radial voice coils 6b, 8b, 9b, a current in the direction D1 flows through the upper columnar portion. Thereby, the electric current of the direction D2 flows into the columnar part below radial voice coil 6b, 8b, 9b. In other words, when the radial voice coils 6b, 8b, and 9b are viewed from the −Y direction toward the + Y direction, a current flows counterclockwise in the ZX plane to the radial voice coils 6b, 8b, and 9b.

  Thereby, the radial voice coils 5b, 6b, 8b, and 9b can generate a thrust in the + Y direction on the permanent magnet movable element 2b. Further, by reversing the current direction in the radial voice coils 5b, 6b, 8b, and 9b, the radial voice coils 5b, 6b, 8b, and 9b cause the permanent magnet movable element 2b to rotate in the Θ direction around the X axis. Can be generated.

  Further, a current (coil current) flows through the permanent magnet movers 2a to 2d in the direction D1 that is the + X direction or the direction D2 that is the -X direction. For example, in the thrust voice coils 10b and 12b, a current in the direction D1 flows through the left columnar portion. As a result, a current in the direction D2 flows through the columnar portion on the right side of the thrust voice coils 10b and 12b. In other words, when the thrust voice coils 10b and 12b are viewed from the + Z direction toward the −Z direction, a current flows counterclockwise in the XY plane to the thrust voice coils 10b and 12b.

  In addition, a current in the direction D2 flows through the left columnar portion of the thrust voice coil 11b. As a result, a current in the direction D1 flows through the columnar portion on the right side of the thrust voice coil 11b. In other words, when the thrust voice coils 10b and 12b are viewed from the + Z direction toward the -Z direction, a current flows clockwise to the thrust voice coil 11b in the XY plane.

  Thereby, the thrust voice coils 10b, 11b, and 12b can generate the thrust in the + Z direction on the permanent magnet movable element 2b. Thus, since the thrust voice coils 10b to 12b are disposed so as to surround the permanent magnet movable element 2b, the thrust voice coils 10b to 12b can generate thrust in the Z direction.

  As described above, in the present embodiment, in the permanent magnet movable element 2b, the radial voice coils 5b, 6b, 8b, 9b and the thrust voice coils 10b to 12b are arranged so as to be orthogonal to each other, and the two are alternately arranged. They are arranged side by side. Further, thrust voice coils 10b, 11b, 12b are arranged inside the radial voice coils 5b, 6b, 8b, 9b. With this configuration, the actuator 100 can be configured to be small and light.

  Next, the magnetic pole property and magnetic path of the permanent magnet movers 2a to 2d will be described. FIG. 5 is a diagram for explaining the magnetic pole property and magnetic path of the permanent magnet mover. FIG. 5 shows an AA cross-sectional view of the voice coil stator 3b as in FIG. The magnetic paths using the permanent magnet movers 2a to 2d are all the same magnetic path, and therefore the magnetic path using the permanent magnet mover 2b will be described here.

  The permanent magnet mover 2b includes permanent magnet segments 13b, 17b, 21b, and 25b that generate radial thrust, permanent magnet segments 14b, 15b, 18b, 19b, 22b, and 23b that generate thrust thrust, and magnetic members that pass magnetic flux. 16b, 20b, 24b.

  The permanent magnet segments 13b, 17b, 21b, and 25b are plate-like members having a main surface parallel to the ZX plane. The permanent magnet segments 14b, 15b, 18b, 19b, 22b, and 23b are plate-like members having a main surface parallel to the ZX plane. The magnetic member 16b is a plate-like member having a main surface parallel to the ZX plane, and is disposed so as to be sandwiched between the permanent magnet segments 14b and 15b. Similarly, the magnetic member 20b is a plate-like member having a main surface parallel to the ZX plane, and is disposed so as to be sandwiched between the permanent magnet segments 18b and 19b. Similarly, the magnetic member 24b is a plate-like member having a main surface parallel to the ZX plane, and is disposed so as to be sandwiched between the permanent magnet segments 22b and 23b. In the following description, a member composed of the permanent magnet segments 14b and 15b and the magnetic member 16b, a member composed of the permanent magnet segments 18b and 19b and the magnetic member 20b, and a permanent magnet segment 22b and 23b and the magnetic member 24b. The members are referred to as thrust thrust generating portions P, Q, and R (not shown), respectively.

  In the permanent magnet movable element 2b, from the + Z direction toward the -Z direction, the permanent magnet segment 13b, the thrust thrust generator P, the permanent magnet segment 17b, the thrust thrust generator Q, the permanent magnet segment 21b, the thrust thrust generator R, These are arranged in the order of the permanent magnet segments 25b.

  Specifically, the permanent magnet segment 13b is disposed between the upper (+ Z side) radial voice coils 5b and 8b, and the permanent magnet segment 17b is disposed between the lower (−Z side) radial voice coils 5b and 8b. Be placed. A thrust thrust generator P having a magnetic member 16b is disposed between the thrust voice coils 10b.

  Similarly, the permanent magnet segment 21b is disposed between the upper radial voice coils 6b and 9b, and the permanent magnet segment 25b is disposed between the lower radial voice coils 6b and 9b. A thrust thrust generator R having a magnetic member 24b is disposed between the thrust voice coils 12b. A thrust thrust generating portion Q having a magnetic member 20b is disposed between the thrust voice coils 11b.

  First, the magnetic path A will be described. The magnetic path A is a magnetic path formed by the upper side of the radial voice coil 5b, the permanent magnet segment 13b, the magnetic member 16b, the permanent magnet segment 14b, and the left side of the thrust voice coil 10b.

  In the magnetic path A, the magnetic flux emitted from the N pole of the permanent magnet segment 13b enters the magnetic member 16b. This magnetic flux penetrates the permanent magnet segment 14b, increases the magnetic flux by the magnetomotive force of the permanent magnet segment 14b, enters the thrust voice coil 10b, returns to the S pole of the permanent magnet segment 13b via the upper side of the radial voice coil 5b.

  A Lorentz force can be generated in the direction D3 that is the -Y direction by flowing a current in the direction D1 that is the + X direction to the upper side of the radial voice coil 5b. Further, a Lorentz force is generated in the direction D4 which is the −Z direction by the magnetic flux of the magnetic path A by flowing a current in the direction D1 which is the + X direction to the left side (−Y side) of the thrust voice coil 10b. Can do. Thus, the magnetic flux of the magnetic path A can contribute to the thrust of both the radial voice coil 5b and the thrust voice coil 10b. The magnetic path B is the same as the magnetic path A.

  Next, the magnetic path C will be described. The magnetic path C is a magnetic field formed by the permanent magnet segment 17b, the magnetic member 16b, the permanent magnet segment 14b, the thrust voice coil 10b, the radial voice coil 5b, the thrust voice coil 11b, the permanent magnet segment 18b, and the magnetic member 20b. Road.

  In the magnetic path C, the magnetic flux emitted from the N pole of the permanent magnet segment 17b enters the magnetic member 16b. This magnetic flux penetrates the permanent magnet segment 14b, increases the magnetic flux by the magnetomotive force of the permanent magnet segment 14b, enters the thrust voice coil 10b, penetrates the lower side of the radial voice coil 5b, and enters the thrust voice coil 11b. The magnetic flux exiting the thrust voice coil 11b enters the south pole of the permanent magnet segment 18b, increases the magnetic flux by the magnetomotive force of the permanent magnet segment 18b, and enters the magnetic member 20b. Further, the magnetic flux exiting the magnetic member 20b returns to the south pole of the permanent magnet segment 17b.

  A Lorentz force can be generated in the direction D3 that is the -Y direction by flowing a current in the direction D2 that is the -X direction to the lower side of the radial voice coil 5b. Further, a current in the direction D1 which is the + X direction is supplied to the left side (−Y side) of the thrust voice coil 10b, and a current in the direction D2 which is the −X direction is supplied to the thrust voice coil 11b. A Lorentz force can be generated in the direction D4, which is the -Z direction, by the magnetic flux. Thus, the magnetic flux in the magnetic path C can contribute to the thrust of both the radial voice coil 5b and the thrust voice coil 11b. The magnetic path D is the same as the magnetic path C.

  Next, the magnetic path E will be described. The magnetic path E is the same as the magnetic path C except that the direction of the current flowing above the radial voice coil 6b is opposite to the direction of the current below the radial voice coil 5b. The magnetic path F is the same as the magnetic path E. Thereby, the magnetic flux of the magnetic paths E and F can contribute to the thrust of both the radial voice coil 6b and the thrust voice coil 12b.

  Next, the magnetic path G will be described. The magnetic path G is the same as the magnetic path A except that the direction of the current flowing to the lower side of the radial voice coil 6b is opposite to the direction of the current on the upper side of the radial voice coil 5b. The magnetic path H is the same as the magnetic path G. Thereby, the magnetic flux of the magnetic paths G and H can contribute to the thrust of both the radial voice coil 6b and the thrust voice coil 12b.

  By controlling the direction and magnitude of the current flowing through the radial voice coils 5b, 6b, 8b, 9b and the thrust voice coils 10b, 11b, 12b, the moving direction and moving distance of the permanent magnet movable element 2b can be controlled. It becomes.

  For example, when the permanent magnet movable element 2b is moved in the Z direction, the direction and magnitude of the current flowing through the thrust voice coils 10b, 11b, and 12b are controlled. Further, when the permanent magnet movable element 2b is moved in the Y direction, the direction and magnitude of the current flowing through the radial voice coils 5b, 6b, 8b, 9b are controlled. When the permanent magnet movable element 2b is rotated in the Θ direction around the X axis, the current direction to the radial voice coils 5b and 6b is different from the current direction to the radial voice coils 8b and 9b.

  Similarly, by using the voice coil stator 3d, the permanent magnet movable element 2d can be moved in the Z direction and the Y direction, and can be rotated in the Θ direction around the X axis.

  Further, by using the voice coil stator 3a, the permanent magnet movable element 2a can be moved in the Z direction and the X direction, and can be rotated in the Φ direction around the Y axis.

  Similarly, by using the voice coil stator 3c, the permanent magnet movable element 2c can be moved in the Z direction and the X direction, and can be rotated in the Φ direction around the Y axis.

  Further, by using at least one of the voice coil stators 3a and 3c and at least one of the voice coil stators 3b and 3d, the movable part can be rotated in the ψ direction around the Z axis.

  As described above, the permanent magnet movable element 2b and the voice coil stator 3b of the present embodiment share the magnetic flux of the radial thrust and the thrust thrust, so that the actuator 100 can be reduced in size and weight. In other words, the magnetic path by the permanent magnet movable element 2b is shared by the radial voice coils 5b, 6b, 8b and 9b and the thrust voice coils 10b to 12b, thereby realizing a reduction in size and weight of the actuator 100.

  Further, the thrust voice coils 10b and 12b are disposed inside the radial voice coils 5b and 8b and the radial voice coils 6b and 9b, and the thrust voice coil 11b is disposed between the radial voice coils 5b and 8b and the radial voice coils 6b and 9b. Since they are arranged, the actuator 100 can be reduced in size and weight.

  FIG. 6 is a diagram for explaining the arrangement positions of the sensors included in the actuator according to the embodiment. FIG. 6 shows the arrangement positions of the sensors 7a to 7f when the permanent magnet movable element 2b, the voice coil stator 3b, and the sensors 7a to 7f are viewed from the upper surface side (from the + Z direction to the −Z direction).

  The sensors 7 a to 7 f are, for example, eddy current displacement meters, and detect a gap (distance) between the actuator movable element 1 made of conductive (for example, aluminum). The sensors 7a and 7e detect the displacement of the actuator movable element 1 in the X direction, and the sensor 7c detects the displacement of the actuator movable element 1 in the Y direction. The sensor 7f detects the displacement of the actuator mover 1 in the Z direction.

The sensors 7a and 7e are both offset from the center Cx of the actuator movable element 1 in the Y direction. Specifically, the sensor 7a is offset from the center Cx of the actuator movable element 1 by a distance L _{R in the} −Y direction, and the sensor 7e is offset from the center Cx of the actuator movable element 1 by a distance L _{R in the} + Y direction. Has been. With this arrangement, the sensors 7a and 7e can detect the rotation angle ψ in the ψ direction around the Z axis.

  Further, a sensor 7b is disposed below the sensor 7a (−Z direction). The sensor 7b can detect the rotation angle φ in the Φ direction around the Y axis in combination with the sensor 7a. Similarly, a sensor 7d is arranged below the sensor 7c (−Z direction). The sensor 7d can detect the rotation angle θ in the Θ direction around the X axis in combination with the sensor 7c.

Sensors 7a, 7b, 7c, 7d, 7e, each detected displacement of 7f, the displacement _{S 1, S 2, S 3} , S 4, S 5, and S _6, the actuator mover revolution angle theta, phi, ψ and translational displacement x, y, z can be expressed by the following equations (1) to (6).

θ = (S ₄ −S ₃ ) / (2L _T ) (1)
φ = (S ₂ −S ₁ ) / (2L _T ) (2)
ψ = (S ₁ + S ₂ ) / (− 2L _R ) (3)
x = (S ₂ −S ₅ ) / 2 (4)
y = (S ₃ + S ₄ −S ₁ −S ₅ ) / 2 (5)
z = S ₆ − (L _YZ (S ₄ −S ₃ ) −L _ZX (S ₂ −S ₁ )) / (2L _T ) (6)

Incidentally, 2L _T here is a sensor 7c, 7d in the Z direction of the arrangement interval (distance). L _R is the distance in the YZ plane between the sensor 7a and the actuator movable element 1, the distance in the ZX plane between the sensor 7c and the actuator movable element 1, or the distance in the YZ plane between the sensor 7e and the actuator movable element 1. . _LR may be a distance in the YZ plane between the sensor 7b and the actuator movable element 1, or a distance in the ZX plane between the sensor 7d and the actuator movable element 1.

  The control device of the actuator 100 detects the rotation angles θ, φ, ψ, and translational displacements x, y, z of the actuator movable element 1 using the above-described equations (1) to (6). Then, the control device controls the current of the voice coils (radial voice coils 5b, 6b, 8b, 9b, thrust voice coils 10b, 11b, 12b), and thereby the actuator movable element 1 (movable part such as a beam condensing lens). Is feedback controlled to a desired value (position).

  In the present embodiment, the case where the voice coil stator 3b includes the radial voice coils 5b and 8b has been described. However, the configuration of the voice coil stator 3b includes one of the radial voice coils 5b and 8b. May be.

  Moreover, although the case where the voice coil stator 3b includes the radial voice coils 6b and 9b has been described, the configuration of the voice coil stator 3b may include one of the radial voice coils 6b and 9b.

  Moreover, although the case where the voice coil stator 3b includes the four radial voice coils 5b, 6b, 8b, and 9b has been described, the voice coil stator 3b may include five or more radial voice coils. Also in this case, the radial voice coil is disposed in the ZX plane, and the permanent magnet movable element 2b is disposed between the radial voice coils.

  Further, in the present embodiment, the case where the actuator 100 includes the four voice coil stators 3a to 3d has been described. However, the configuration of the actuator 100 includes one of the voice coil stators 3a and 3c. There may be. Similarly, the configuration of the actuator 100 may be a configuration including any one of the voice coil stators 3b and 3d.

  The configuration of the actuator 100 may be a configuration including either one of the permanent magnet movers 2a and 2c. Similarly, the configuration of the actuator 100 may be a configuration including any one of the permanent magnet movers 2b and 2d. Further, the permanent magnet movers 2 a to 2 d and the voice coil stators 3 a to 3 d may be arranged at the center of the actuator mover 1.

  The actuator 100 according to the present embodiment feedback-controls all six degrees of freedom with electromagnetic force, and thus is completely non-contact with the movable part. Thereby, a mechanical holding mechanism becomes unnecessary, and the actuator 100 can be configured to be small and light.

  In addition, since the movable part is completely non-contact, the movable part can be operated without mechanical sliding. Therefore, the life of the actuator 100 is extended, and maintenance such as addition of lubricating oil can be simplified.

  As described above, according to the embodiment, since all six degrees of freedom of XYZ translation and rotation around XYZ are controlled by the Lorentz force of the voice coil, it is possible to increase the stroke of the movable part.

  Further, since the magnetic circuits in the Z direction and the XY direction can be arranged without being separated, the entire size of the actuator 100 can be reduced. In addition, since the permanent magnet movers 2 a to 2 d and the voice coil stators 3 a to 3 d are arranged so as to surround the central portion of the actuator 100, a movable portion can be arranged in the central portion of the actuator 100.

  In addition, since the movable part can be operated without mechanical sliding, the power consumption is reduced by 14 to 25%, and an effect close to the numerical optimum solution is obtained, and the numerical optimum solution is obtained. Therefore, it is possible to provide an approximate solution that can be implemented in real time and online, which is difficult.

  As described above, the actuator according to the present invention is suitable for positioning performed by levitating the movable part with electromagnetic force.

DESCRIPTION OF SYMBOLS 1 Actuator mover 2a-2d Permanent magnet mover 3a-3d Voice coil stator 5b, 6b, 8b, 9b Radial voice coil 7a-7f Sensor 10b-12b Thrust voice coil 13b-15b, 17b-19b, 21b-23b, 25b Permanent magnet segment 16b, 20b, 24b Magnetic member 100 Actuator AH Magnetic path

Claims (5)

A first voice coil stator comprising a first radial voice coil whose first plane is a winding plane and a first thrust voice coil whose second plane perpendicular to the first plane is a winding plane; ,
Generating a first magnetic flux penetrating through the first radial voice coil and the first thrust voice coil, causing a first coil current to flow through the first radial voice coil , and the first thrust; A first permanent magnet mover that is moved by passing a second coil current through the voice coil;
A second voice comprising a second radial voice coil in which a third plane perpendicular to the first and second planes is a winding plane and a second thrust voice coil in which the second plane is a winding plane. A coil stator;
Generating a second magnetic flux penetrating the second radial voice coil and the second thrust voice coil, passing a third coil current through the second radial voice coil , and the second thrust. A second permanent magnet mover that is moved by passing a fourth coil current through the voice coil;
An actuator mover positioned by movement of the first and second permanent magnet movers;
Have
The first permanent magnet mover is moved by a Lorentz force generated by the first magnetic flux and the first and second coil currents;
The second permanent magnet mover is moved by a Lorentz force generated by the second magnetic flux and the third and fourth coil currents;
The actuator movable element is driven and controlled by three axial rotation angles and six degrees of freedom of translational displacement in three directions by the movement of the first and second permanent magnet movable elements.   2. The actuator according to claim 1, wherein the first permanent magnet movable element is disposed so as to penetrate the first thrust voice coil.   The actuator according to claim 1, wherein the first thrust voice coil is disposed so as to pass through an inner ring portion of the first radial voice coil.   The first voice coil stator and the first permanent magnet mover, and the second voice coil stator and the second permanent magnet mover are respectively disposed on the outer periphery of the actuator mover. The actuator according to any one of claims 1 to 3, wherein the actuator is provided. A plurality of the first radial voice coils are arranged in the first plane, and a plurality of the second radial voice coils are arranged in the third plane,
When rotating the actuator mover in the axial direction perpendicular to the second plane,
The first coil current is caused to flow in different directions for each of the first radial voice coils, and the third coil current is caused to flow in different directions for each of the second radial voice coils. The actuator according to any one of claims 1 to 4.

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