JP2003348860A - Dual flexible driver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dual flexible driver which can measure an inclining positions of an output shaft, a member to be driven or the like provided at a plurality of rotors rotating at an axial center while enabling a simple wiring structure to be formed. <P>SOLUTION: The dual flexible driver comprises a stator 2 having a contact section 6b for generating vibration in a plurality of directions at the contact section 6b, and the rotors 3 having a spherical section 13 formed in a substantially spherical shape with the section 13 brought into pressure contact with the section 6b. The driver rotates at the plurality of the axial centers based on the bibrations in the plurality of directions generated by a stator 2. An electrostatic capacity variable section 16 changing in the electrostatic capacity at the terminal disposed at a predetermined position in response to the rotation of itself is provided at the section 13 of the rotor 3. A detecting terminal 21 of an electrostatic capacity sensor S1 for measuring the electrostatic capacity is provided at the predetermined position. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiple-degree-of-freedom drive device for rotating a rotor about a plurality of axes.

[0002]

2. Description of the Related Art In recent years, a multi-degree-of-freedom driving device for rotating a rotor about a plurality of axes has been proposed. The stator of this multiple-degree-of-freedom drive device is provided with a piezoelectric element so that vibrations in a plurality of directions can be generated at the contact portion. The rotor has a substantially spherical spherical portion pressed into contact with the contact portion. The rotor (spherical portion) rotates about a plurality of axes based on vibrations generated in the stator in a plurality of directions. An output shaft and a driven member are connected to or integrally formed with the spherical portion of the rotor, and they are tilted by the rotation.

[0003]

By the way, it is conceivable that the above-described multiple-degree-of-freedom drive device is mounted on a working arm robot, an animal-type toy robot, or the like.
In such a case, it is necessary to accurately control the position of the output shaft and the driven member. Therefore, in such a multiple-degree-of-freedom drive device, a sensor (such as an acceleration sensor) for detecting the tilt position is provided on the output shaft or the driven member.

However, if a sensor is provided on an output shaft or a driven member that moves (tilts) significantly with respect to the rotation of the spherical portion, the wiring structure of the sensor becomes complicated to allow the sensor to move. Problem.

An object of the present invention is to provide a multi-degree-of-freedom drive device capable of measuring a tilt position of an output shaft, a driven member, and the like provided on a rotor rotating about a plurality of axes while enabling a simple wiring structure. Is to provide.

[0006]

According to a first aspect of the present invention, there is provided a stator having a contact portion, a stator for generating vibrations in a plurality of directions at the contact portion, and a spherical portion formed in a substantially spherical shape. ,
A rotor whose spherical portion is pressed against the contact portion, and a multiple-degree-of-freedom drive device that rotates the rotor around a plurality of axes based on vibrations in a plurality of directions generated by the stator. The spherical portion of the rotor is provided with a capacitance variable portion in which the capacitance at a terminal arranged at a predetermined position changes according to its own rotation, and the capacitance is measured at the predetermined position. The capacitance sensor was provided.

According to a second aspect of the present invention, in the multiple-degree-of-freedom drive device according to the first aspect, the stator is held and the spherical portion is rotatably held. A detection terminal forming a part of the capacitance sensor is provided in the case.

[0008] The invention described in claim 3 is the first or second invention.
In the multiple-degree-of-freedom drive device described in the above, the capacitance variable portion is provided in a band shape along the outer periphery of the spherical portion, and a detection terminal forming a part of the capacitance sensor, the spherical portion and the A plurality was provided in the circumferential direction with the pressing contact direction with the stator as the axis center, and a plurality of rows were provided in the pressing contact direction and fixed to the stator around the spherical portion.

The invention described in claim 4 is the first or second invention.
In the multiple-degree-of-freedom drive device described in the above, the capacitance variable portion, a space is formed inside the spherical portion, and a conductive viscous fluid less than the volume of the space is put in the space,
A plurality of detection terminals constituting a part of the capacitance sensor are provided in a circumferential direction around the axis of a pressing contact between the spherical portion and the stator at a basic position, and a plurality of detection terminals are provided in the pressing contact direction. It was fixed to the outer periphery of the spherical part.

The invention according to claim 5 has a contact portion,
A stator that generates vibrations in a plurality of directions at the contact portion, a rotor having a spherical portion formed in a substantially spherical shape, and the spherical portion being pressed into contact with the contact portion, is generated by the stator. In a multiple-degree-of-freedom drive device that rotates the rotor about a plurality of axes based on vibrations in a plurality of directions, a magnetic force at a predetermined position changes in the spherical portion of the rotor in accordance with its own rotation. And a magnetic sensor for measuring a magnetic force is provided at the predetermined position.

(Operation) According to the first aspect of the present invention,
The rotor is rotated around a plurality of axes based on vibrations generated in the stator in a plurality of directions. Then, the capacitance according to the rotation of the rotor is measured by the capacitance sensor. Therefore, the rotational position of the rotor can be measured based on the measurement result of the capacitance sensor, and the tilting position of the output shaft or driven member connected to or integrally formed with the spherical portion can be measured. The measurement can be performed without providing a sensor in the apparatus.

According to the second aspect of the present invention, the stator, the spherical portion, and the detection terminal constituting a part of the capacitance sensor are substantially housed in the case. Therefore, the appearance becomes good. According to the third aspect of the present invention, the variable capacitance portion is provided in a band along the outer periphery of the spherical portion.
In addition, a detection terminal that forms a part of the capacitance sensor,
A plurality of the spherical portions are provided in a circumferential direction around the pressing contact direction between the stator and the stator, and are fixed to the stator around the spherical portion so as to be provided in a plurality of rows in the pressing contact direction. Therefore, when the rotor rotates, the capacitance measured at each of the detection terminals changes, and the rotation position of the rotor is measured based on the measurement result. In this case, since the detection terminal is fixed to the stator, a simple wiring structure that does not allow movement can be provided.

According to the fourth aspect of the present invention, the capacitance variable section is formed by forming a space inside the spherical section, and filling the space with a conductive viscous fluid smaller than the volume of the space. Is done. Also, a plurality of detection terminals constituting a part of the capacitance sensor are provided in a circumferential direction around an axis of a pressing contact between the spherical portion and the stator at a basic position, and a plurality of detection terminals are arranged in the pressing contact direction. It is fixed to the outer periphery of the spherical portion so as to be provided. Therefore, when the rotor (spherical portion) rotates, the conductive viscous fluid moves in space with respect to the spherical portion. Then, the capacitance measured at each of the detection terminals fixed to the outer periphery of the spherical portion changes, and the rotational position of the rotor is measured based on the measurement result. In this case, the detection terminal moves with respect to the stator, and a wiring structure that can cope with the movement of the detection terminal is required. However, the detection terminal is rotated as compared with the case where the sensor is provided on the output shaft or the driven member. Since the moving distance is small, the wiring structure is simplified.

According to the fifth aspect of the invention, the rotor is rotated about a plurality of shafts based on vibrations generated in the stator in a plurality of directions. Then, the magnetic force according to the rotation of the rotor is measured by the magnetic sensor. Therefore, the rotation position of the rotor can be measured based on the measurement result of the magnetic sensor, and the tilting position of the output shaft or driven member connected to or integrally formed with the spherical portion is detected by the driven member or the like. Can be measured without providing a

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, the multiple-degree-of-freedom drive device includes a case 1, a stator 2, a rotor 3, and a capacitance sensor S1.

The case 1 includes a case body 4 and a bearing 5. The case body 4 includes a cylindrical portion 4a having a substantially cylindrical shape, and a bottom portion 4b for closing a base end (a lower end in FIG. 1) of the cylindrical portion 4a.

The bearing 5 is formed in an annular shape, and has a spherical surface provided on the base end side (the lower side in FIG. 1) of the inner peripheral surface thereof so as to come into contact with a spherical surface provided below at an annular surface. Support surface 5a
Are formed. The outer peripheral edge of the bearing 5 is fixed to the tip (the upper end in FIG. 1) of the cylindrical portion 4a.

The stator 2 is fixed (held) in the case 1.
And the rotor 3 is rotatably held. The case 1 substantially accommodates the stator 2 and the rotor 3. More specifically, the stator 2 includes upper and middle blocks 6 and 7 and first to third piezoelectric elements 8 to 10.

The upper and middle blocks 6, 7 are made of a conductive metal, and in this embodiment, are made of an aluminum alloy. The upper and middle blocks 6 and 7 are substantially cylindrical bodies, and have through holes formed in the center axis thereof so as to penetrate in the axial direction. In the center of the upper part of the upper block 6, a recess 6
a is recessed from above. The opening of the recess 6a is formed with a curved contact portion 6b set to be in contact with a spherical surface provided above and an annular surface.

The first to third piezoelectric elements 8 to 10 are respectively composed of two piezoelectric elements 8a, 8b to 10
a and 10b are combined, and a through-hole is formed in the central shaft portion.

The polarization direction of one of the piezoelectric elements 8a constituting the first piezoelectric element 8 is perpendicular to the plane (thickness direction).
And it is inverted by half of the plane. Also, the first
The polarization direction of the other piezoelectric element 8b constituting the piezoelectric element 8 is opposite to that of the one piezoelectric element 8a, that is, symmetric with respect to the one piezoelectric element 8a about an electrode (not shown) provided on the mating surface (combining surface). Have been.

The polarization direction of one of the piezoelectric elements 9a constituting the second piezoelectric element 9 is perpendicular to the plane (thickness direction).
And it is inverted by half of the plane. Also, the second
The polarization direction of the other piezoelectric element 9b constituting the piezoelectric element 9 is opposite to that of the one piezoelectric element 9a, that is, one of the piezoelectric elements 9b is centered on an electrode (not shown) provided on the mating surface.
a.

The polarization direction of one of the piezoelectric elements 10a constituting the third piezoelectric element 10 is one direction perpendicular to the plane. The polarization direction of the other piezoelectric element 10b constituting the third piezoelectric element 10 is opposite to that of the one piezoelectric element 10a.
That is, it is symmetrical to one of the piezoelectric elements 10a about an electrode (not shown) provided on the mating surface. still,
Unillustrated electrodes are provided on the upper and lower surfaces of the first to third piezoelectric elements 8 to 10, respectively.

The third piezoelectric element 10, the middle block 7, the second piezoelectric element 9, the first piezoelectric element 8, the upper block 6
Are stacked in this order, and a nut 12 is attached to the tip of a bolt member 11 which is erected from the bottom 4b and inserted into each through hole.
Are screwed into each other, and the bottom 4b
Fixed to.

At this time, the first piezoelectric element 8 and the second piezoelectric element 9 are arranged so that the polarization boundary is shifted by 90 ° (perpendicular). The rotor 3 includes a substantially spherical portion 13 and an output shaft 14 protruding from the spherical portion 13. When the spherical portion 13 is sandwiched between the contact portion 6b of the stator 2 and the spherical support surface 5a of the bearing 5, the rotor 3 is pressed against the contact portion 6b and rotates about a plurality of axes. Supported as possible.
At this time, the output shaft 14 is protruded outward (upward in FIG. 1) from the center hole of the bearing 5 on the substantially opposite side of the contact portion 6b. Also, at the tip of the output shaft 14,
The driven member 15 is connected.

The spherical portion 13 is provided with a variable capacitance portion 16 whose capacitance at a terminal arranged at a predetermined position changes according to its own rotation. Specifically, the capacitance variable section 16 is provided in a band shape along the outer periphery of the spherical section 13. The capacitance variable portion 16 is configured by forming an insulating portion 17 made of a resin material in a strip shape along the outer periphery of the spherical portion 13 made of a metal material.

The capacitance sensor S1 is provided at the predetermined position. Specifically, the capacitance sensor S1 includes a detection terminal 21 and a position detection circuit 22. The detection terminal 21 is housed in the case 1. Detection terminal 21
Is the pressing contact direction between the spherical portion 13 and the stator 2 (FIG. 1).
It is fixed to the inner peripheral surface of the cylindrical portion 4a around the spherical portion 13 so as to be provided in a plurality in the circumferential direction centered on the center (vertical direction) and to be provided in a plurality of rows in the pressing contact direction. As schematically shown in FIG. 2, 24 detection terminals 21 of the present embodiment are provided at equal angular (15 °) intervals in the circumferential direction. The detection terminals 21 are provided in two rows in the pressing contact direction (vertical direction in FIG. 1). The detection terminal 21 is arranged such that the output shaft 14 of the rotor 3 is in a pressing contact direction (FIG. 1).
In the basic position facing (middle, upward), the upper row is arranged so that the lower part of the upper row faces the insulating part 17 and the upper part of the lower row faces the insulating part 17 (at the predetermined position). Have been. Each detection terminal 21 is electrically connected to a position detection circuit 22 (in FIG. 1, each detection terminal 2
The connection state is indicated by an arrow only for two of 1).

The position detection circuit 22 measures the capacitances C1 to Cn at the respective detection terminals 21 and, based on the measurement results, the rotational position (state) of the rotor 3 (spherical portion 13) and the driven member 15 (Tilting position) is calculated (measured). The position detection circuit 22 is electrically connected to the target value setting circuit 23 and outputs a tilt information signal K1 indicating the tilt position (state) of the driven member 15 to the target value setting circuit 23.

The target value setting circuit 23 is electrically connected to the actuator drive circuit 24. The target value setting circuit 23 outputs the driven member 15 based on the tilt information signal K1.
A target value signal M1 including information for causing the tilted state of the driven member 15 to approach the tilted state of the driven member 15 set (operated) in advance is output to the actuator drive circuit 24.

The actuator drive circuit 24 includes the first
To the third piezoelectric elements 8 to 10 (the electrodes thereof),
First to third piezoelectric elements 8 to 10 based on target value signal M1.
To drive the stator 2.

More specifically, the actuator drive circuit 24
Is between the electrode on the upper surface of the first piezoelectric element 8 and the electrode on the mating surface,
The same high-frequency voltage is supplied between the electrode on the lower surface of the first piezoelectric element 8 and the electrode on the mating surface. Actuator drive circuit 2
4 supplies the same high-frequency voltage between the electrode on the upper surface of the second piezoelectric element 9 and the electrode on the mating surface, and between the electrode on the lower surface of the second piezoelectric element 9 and the electrode on the mating surface. Further, the actuator drive circuit 24 supplies the same high-frequency voltage between the electrode on the upper surface of the third piezoelectric element 10 and the electrode on the mating surface, and between the electrode on the lower surface of the third piezoelectric element 10 and the electrode on the mating surface. At this time,
From the actuator drive circuit 24 to the first to third piezoelectric elements 8
The time phase difference between the high-frequency voltages supplied to the high-frequency voltages supplied to the target value signal M1 is a value based on the target value signal M1.

Then, a vertically symmetrical high-frequency voltage is supplied to the first piezoelectric element 8 using the electrode of the mating surface as a common electrode, and the polarization directions of the one piezoelectric element 8a and the other piezoelectric element 8b are changed to the electrodes of the mating surface. Are symmetrical about the first piezoelectric element 8, which is large (piezoelectric elements 8 a and 8 b
(The sum of the vibrations of the two) is generated. Since the polarization directions of the piezoelectric elements 8a and 8b are opposite to each other by half of the plane, the vibration of the piezoelectric elements 8a and 8b is contracted when one of the divided elements expands in the thickness direction, and the other is contracted when one of the divided elements contracts. Become.

In the second piezoelectric element 9, the first piezoelectric element 8
Similarly, when one of the divided parts expands in the thickness direction, the other contracts, and conversely, when one of the parts contracts, a large vibration is generated in which the other part expands. The vibration generated at this time is such that the boundary between the polarization of the first piezoelectric element 8 and the second piezoelectric element 9 is 90 degrees.
The first piezoelectric element 8 is different from the vibration by 90 ° (at right angles) because the first piezoelectric element 8 is disposed so as to be shifted by 90 °.

Further, a vertically symmetric high-frequency voltage is supplied to the third piezoelectric element 10 using a common electrode on the mating surface, and the polarization directions of the one piezoelectric element 10a and the other piezoelectric element 10b are adjusted to match the electrodes on the mating surface. , A large vibration is generated in the third piezoelectric element 10. Since the polarization direction of each of the piezoelectric elements 10a and 10b is one direction in the entire plane, this vibration is a longitudinal vibration in which the upper surface to the lower surface uniformly expand and contract.

Then, at the contact portion 6b of the stator 2, a composite vibration based on each vibration of the first to third piezoelectric elements 8 to 10 is generated, the spherical portion 13 is rotated, and the output shaft 1 is rotated.
4 and the driven member 15 are tilted to a tilt state set (operated) in advance (see FIG. 3).

That is, in this multiple-degree-of-freedom drive device, when the rotor 3 rotates (for example, as shown in FIG. 3, rotates counterclockwise about the axis perpendicular to the plane of the paper), the capacitance C1 at each detection terminal 21 is increased. ＣCn changes (for example, the capacitances C1 and C2 increase and decrease in the upper and lower rows of the left detection terminal 21 in FIG. 3). Then, the rotation position (state) of the rotor 3 (spherical portion 13) and the tilt position (state) of the driven member 15 are calculated (measured) by the position detection circuit 22 based on the measurement result, and the tilt information signal is calculated. K1 is output to the target value setting circuit 23. Then, the target value signal M1 is output from the target value setting circuit 23 to the actuator drive circuit 24 until the tilt state of the driven member 15 matches the tilt state of the driven member 15 set (operated) in advance, and the target value signal M1 is set in advance ( The driven member 15 is tilted until it coincides with the tilted state of the driven member 15 that has been operated.

Next, the characteristic operation and effect of the first embodiment will be described below. (1) When the rotor 3 rotates, the electrostatic capacitances C1 to Cn at the respective detection terminals 21 change due to the rotation of the electrostatic capacitance variable portion 16 (insulating portion 17) provided on the spherical portion 13. Then, the capacitances C1 to Cn are measured by the position detection circuit 22. Therefore, the rotation position (state) of the rotor 3 (spherical portion 13) and the tilt position (state) of the driven member 15 are determined based on the measurement results without providing a sensor on the output shaft 14 or the driven member 15. Can be calculated (measured). Therefore, the wiring structure does not become complicated as in the case where a sensor is provided on the output shaft 14 and the driven member 15 which move (tilt) significantly with respect to the rotation of the spherical portion 13.

(2) Stator 2, rotor 3 (spherical portion 1)
3), and the detection terminal 21 of the capacitance sensor S1 is substantially accommodated in the case 1. Therefore, the appearance becomes good. (3) The capacitance variable portion 16 is provided in a band shape along the outer periphery of the spherical portion 13. The detection terminal 21 is connected to the spherical portion 13.
A plurality of (24) spherical portions 13 are provided in the circumferential direction centered on the pressing contact direction (vertical direction in FIG. 1) between the motor and the stator 2 and the plurality of spherical portions 13 Is fixed to the inner peripheral surface of the cylindrical portion 4a. Therefore, when the rotor 3 (spherical portion 3) rotates, the capacitances C1 to Cn measured at the respective detection terminals 21 change, and the rotational position of the rotor 3 is measured based on the measurement result. . In this case, the detection terminal 21
Is fixed to the stator 2, so that a simple wiring structure that does not allow the detection terminal 21 to move can be provided.

(4) Since 24 detection terminals 21 are provided at equal angular (15 °) intervals in the circumferential direction, the measurement accuracy of the rotational position of the rotor 3 (spherical portion 13) can be made uniform. it can.

(5) Since the variable capacitance portion 16 is formed by forming an insulating portion 17 made of a resin material in a strip shape along the outer periphery of the spherical portion 13 made of a metal material, the variable capacitance portion 16 is formed. Can be easily provided as a simple configuration.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to FIGS. In the second embodiment, the same members (such as the stator 2) as those in the first embodiment are denoted by the same reference numerals, and a detailed description thereof will be partially omitted. As shown in FIG. 4, the multiple-degree-of-freedom driving device includes a case 31 and a stator 2.
, A rotor 32, and a capacitance sensor S2.

The case 31 includes a case body 33 and the bearing 5. The case body 33 includes a substantially cylindrical cylindrical portion 33a and a base end portion of the cylindrical portion 33a (FIG. 4).
And a bottom portion 33b for closing the middle and lower ends.

In the case 31, the stator 2 is fixed (held), and the rotor 32 is rotatably held. The case 31 includes the stator 2 and the rotor 32.
Is almost accommodated.

The rotor 32 has a substantially spherical spherical portion 34 and an output shaft 35 projecting from the spherical portion 34.
When the spherical portion 34 is sandwiched between the contact portion 6b of the stator 2 and the spherical support surface 5a of the bearing 5, the rotor 32 is pressed against the contact portion 6b and rotates about a plurality of axes. Supported as possible. At this time, the output shaft 35 is protruded outward (upward in FIG. 1) from the center hole of the bearing 5 on the substantially opposite side of the contact portion 6b.
In addition, the driven member 15
Will be connected.

The spherical portion 34 is provided with a variable capacitance portion 36 whose capacitance at a terminal arranged at a predetermined position changes according to its own rotation. More specifically, the variable capacitance unit 36 is configured by forming a space 37 inside the spherical portion 34 and sealing (entering) a conductive viscous fluid 38 in the space 37 that is smaller than the volume of the space 37. I have. In the present embodiment, a space 37 is formed inside the insulating cover 39 by forming a part of the outer surface of the spherical portion 34 with the insulating cover 39 made of a resin material and having an arc-shaped cross section. Since the insulating cover 39 has a constant thickness, the space 37 has a constant distance from the outer periphery of the spherical portion 34. Further, the space 37 is formed such that the cross section in the pressing contact direction (see FIG. 4) has an arc shape centered on the center of the spherical portion 34.

The capacitance sensor S2 is provided at the predetermined position. Specifically, the capacitance sensor S2 includes a detection terminal 41 and a position detection circuit 42. The detection terminal 41 is housed in the case 31. Detection terminal 4
1 indicates that the output shaft 35 of the rotor 32 has a pressing contact direction (FIG. 4).
At the basic position facing the middle, upward), a plurality of fixing members are provided on the outer periphery of the spherical portion 34 (insulating cover 39) so as to be provided in the circumferential direction with the pressing contact direction as the axis and to be provided in a plurality of rows in the pressing contact direction. Have been. As schematically shown in FIG. 5, twelve detection terminals 41 of the present embodiment are provided at equal angular (30 °) intervals in the circumferential direction.
The detection terminals 41 are provided in three rows in the pressing contact direction (the vertical direction in FIG. 4). The detection terminals 41 are arranged (at the predetermined position) such that the substantially central row faces the conductive viscous fluid 38 at the basic position (see FIG. 4). Each of the detection terminals 41 is electrically connected to the position detection circuit 42 (in FIG. 4, only three of the detection terminals 41 are connected by broken lines). Each of the detection terminals 41 is connected to the position detection circuit 42 by a bendable conductor so that the connection state is maintained even if the detection terminal 41 moves, as shown by a broken line in FIG.

The position detection circuit 42 measures the capacitances C1 to Cn at the respective detection terminals 41 and, based on the measurement results, the rotational position (state) of the rotor 32 (spherical portion 34) and the driven member 15 (Tilting position) is calculated (measured). The position detection circuit 42 is electrically connected to the target value setting circuit 43 and outputs a tilt information signal K2 indicating the tilt position (state) of the driven member 15 to the target value setting circuit 43.

The target value setting circuit 43 is electrically connected to the actuator driving circuit 44. The target value setting circuit 43 outputs the driven member 15 based on the tilt information signal K2.
A target value signal M2 including information for causing the tilted state of the driven member 15 to approach the tilted state of the driven member 15 set (operated) in advance is output to the actuator drive circuit 44.

The actuator drive circuit 44, like the actuator drive circuit 24, is connected to the first to third piezoelectric elements 8 to 10 (the electrodes thereof), and receives the first to third piezoelectric elements 8 to 10 based on the target value signal M2. A high-frequency voltage is supplied to the piezoelectric elements 8 to 10 to drive the stator 2.

Then, in the contact portion 6b of the stator 2, a composite vibration based on each vibration of the first to third piezoelectric elements 8 to 10 is generated, the spherical portion 34 is rotated, and the output shaft 3 is rotated.
5 and the driven member 15 are tilted to a tilt state set (operated) in advance (see FIG. 6).

That is, in this multiple-degree-of-freedom drive device, when the rotor 32 rotates (for example, as shown in FIG. 6, rotates leftward about the center of the axis perpendicular to the plane of the paper), the capacitance C1 at each detection terminal 41 is increased. ＣCn changes (for example, in FIG. 6, the capacitance C1 increases in the upper row of the left detection terminal 41). Then, the position detection circuit 42 calculates (measures) the rotational position (state) of the rotor 32 (spherical portion 34) and the tilt position (state) of the driven member 15 based on the measurement result, and outputs a tilt information signal. K2 is output to the target value setting circuit 43. Then, the target value setting circuit 43 outputs the target value signal M2 from the target value setting circuit 43 to the actuator drive circuit 44 until the tilt state of the driven member 15 matches the tilt state of the driven member 15 which has been set (operated) in advance. The driven member 15 is tilted until it coincides with the tilted state of the driven member 15 that has been operated.

Next, the characteristic operation and effect of the second embodiment will be described below. (1) When the rotor 32 rotates, the conductive viscous fluid 38 of the variable capacitance unit 36 moves in the space 37 with respect to the spherical portion 34, so that the capacitance C1 at each detection terminal 41 is changed.
〜Cn change, and the capacitances C1１〜Cn are measured by the position detection circuit 42. Therefore, without providing a sensor on the output shaft 35 or the driven member 15, the rotational position (state) of the rotor 32 (spherical portion 34) is determined based on the measurement result.
And the tilt position (state) of the driven member 15 is calculated (measured).
can do. Therefore, the wiring structure does not become complicated as in the case where a sensor is provided on the output shaft 35 and the driven member 15 that move (tilt) significantly with respect to the rotation of the spherical portion 34. Specifically, the detection terminal 41 moves with respect to the stator 2, and a wiring structure that can cope with the movement of the detection terminal 41 is required. However, compared to a case where a sensor is provided on the output shaft 35 or the driven member 15, Therefore, since the moving distance at the time of rotation is small, the wiring structure can be simplified.

(2) Stator 2, rotor 32 (spherical portion 3)
4) and the detection terminal 41 of the capacitance sensor S2 is substantially accommodated in the case 31. Therefore, the appearance becomes good. (3) Since the detection terminals 41 are provided (12) at equal angular (30 °) intervals in the circumferential direction, the rotor 32 (spherical portion 34)
The measurement accuracy of the rotational position of can be made uniform.

(4) Since the space 37 is formed so that the distance from the outer periphery of the spherical portion 34 is constant, the rotor 32
The measurement accuracy of the rotational position of the (spherical portion 34) can be made uniform.

(5) Since the space 37 is formed such that its cross section in the pressing contact direction (see FIG. 4) has an arc shape centered on the center of the spherical portion 34, the amount of the conductive viscous fluid 38 is reduced. Thus, the effect (4) can be obtained.

The above embodiments may be modified as follows. In the first embodiment, the spherical portion 13 is provided with the capacitance variable portion 16, but instead of the capacitance variable portion 16,
As shown in FIG. 7, a magnetic force varying unit 61 that changes the magnetic force at a predetermined position according to its own rotation may be provided. In this case, the capacitance sensor S1 of the first embodiment is changed to a magnetic sensor S3 for measuring a magnetic force.

More specifically, the magnetic force varying portion 61 is
The permanent magnet portion 63 is formed in a belt shape along the outer periphery of. The magnetic sensor S3 has a magnetic detection terminal 6
4 and a position detection circuit 65. The magnetic detection terminal 64 is provided in the same manner as the detection terminal 21. The position detection circuit 65 measures the magnetic forces G1 to Gn at the respective magnetic detection terminals 64, and based on the measurement results, the rotational position (state) of the rotor 66 (spherical portion 62) and the tilting of the driven member 15 Calculate (measure) the position (state). The position detection circuit 65 is electrically connected to the target value setting circuit 23, and outputs a tilt information signal K3 indicating the tilt position (state) of the driven member 15 to the target value setting circuit 23.

In this way, when the rotor 66 rotates, the magnetic force variable portion 61 (permanent magnet portion 63) provided on the spherical portion 62 rotates, so that each magnetic detection terminal 6 is rotated.
4, the magnetic forces G1 to Gn change, and the magnetic forces G1 to Gn are measured by the position detection circuit 65. Therefore, without providing a sensor on the output shaft 67 or the driven member 15, the rotation position (state) of the rotor 66 (spherical portion 62) and the tilt position (state) of the driven member 15 based on the measurement results. Can be calculated (measured). Therefore, the wiring structure does not become complicated as in the case where a sensor is provided on the output shaft 67 and the driven member 15 that move (tilt) significantly with respect to the rotation of the spherical portion 62.

In the above embodiments, the stator 2, the rotors 3, 32 (spherical portions 13, 34), and the detection terminals 21, 41 of the capacitance sensors S1, S2 are substantially housed in the cases 1, 31. Alternatively, the configuration may not be accommodated in the cases 1 and 31. That is, the cases 1 and 31 may be appropriately changed. Even in this case, the effects (1) and (3) to (5) of the first embodiment or the effects (1) and (3) to (5) of the second embodiment are the same. The effect of can be obtained.

In each of the above embodiments, the spherical portion is provided with a capacitance variable portion in which the capacitance at a terminal arranged at a predetermined position changes according to the rotation of the spherical portion. If a capacitance sensor for measuring the capacitance is provided, another configuration may be used.

The insulating part 17 of the first embodiment is
It may be formed of an insulating material other than the resin material. Even in this case, the same effect as that of the first embodiment can be obtained.

In the first embodiment, the detection terminal 2
As shown in FIG. 2, 1 is provided at equal angular (15 °) intervals (24) in the circumferential direction, but may be provided at unequal angular intervals. Even in this case, effects similar to the effects (1) to (3) and (5) of the first embodiment can be obtained.

In the second embodiment, the detection terminal 4
As shown in FIG. 5, 12 are provided at equal angular (30 °) intervals in the circumferential direction, but may be provided at unequal angular intervals. Even in this case, effects similar to the effects (1), (2), (4), and (5) of the second embodiment can be obtained.

In the first embodiment, the detection terminal 2
Although 24 are provided in the circumferential direction as shown in FIG. 2, the number may be changed as appropriate. In the first embodiment, the detection terminals 21 are provided in two rows as shown in FIG. 1, but the number of the rows may be changed as appropriate. Even in this case, the same effect as that of the first embodiment can be obtained. Note that, when the number of detection terminals 21 and the number of columns are increased, detection accuracy is improved. Also, detection terminal 2
When the number of 1s and the number of columns are reduced, a simpler wiring structure can be obtained.

In the second embodiment, the detection terminal 4
Although 12 are provided in the circumferential direction as shown in FIG. 5, the number may be changed as appropriate. In the second embodiment, the detection terminals 41 are provided in three rows as shown in FIG. 4, but the number of the rows may be changed as appropriate. Even in this case, the same effect as the effect of the second embodiment can be obtained. In addition, if the number of detection terminals 41 and the number of columns are increased, the detection accuracy will be improved. Also, detection terminal 4
When the number of 1s and the number of columns are reduced, a simpler wiring structure can be obtained.

In the second embodiment, the space 37
Is formed such that the distance from the outer periphery of the spherical portion 34 is constant, but may be formed so that the distance from the outer periphery of the spherical portion 34 is not constant. In this case, the position detection circuit 42 calculates (measures) the rotational position (state) of the rotor 32 (spherical portion 34) and the tilt position (state) of the driven member 15 according to the shape (distance). Must be set in advance as follows. Even in this case, effects similar to the effects (1) to (3) of the second embodiment can be obtained.

In the second embodiment, the space 37
Is formed such that its cross section in the pressing contact direction (see FIG. 4) has an arc shape centered on the center of the spherical portion 34, but has another shape (for example, the cross section has a substantially hemispherical shape, etc.). ). Even in this case, the second
The same effects as the effects (1) to (4) of the embodiment can be obtained.

The stator 2 of each of the above embodiments may be changed to another configuration as long as it can generate vibrations in a plurality of directions to rotate the rotors 3 and 32 around a plurality of axes.

The technical ideas that can be grasped from the above embodiments and other examples will be described below together with their effects. (A) The multiple-degree-of-freedom drive device according to claim 3, wherein the detection terminals are provided at equal angular intervals in the circumferential direction. By doing so, the measurement accuracy of the rotational position of the rotor can be made uniform.

(B) In the multiple-degree-of-freedom drive device according to (3) or (A), the spherical portion is formed of a metal material, and the variable capacitance portion is provided on the outer periphery of the spherical portion. A double-degree-of-freedom drive device characterized by being formed by forming a resin material in a belt shape along the same. This makes it possible to easily provide the variable capacitance unit.

(C) The multiple-degree-of-freedom drive device according to claim 4, wherein the detection terminals are provided at equal angular intervals in the circumferential direction. By doing so, the measurement accuracy of the rotational position of the rotor can be made uniform.

(D) In the multiple-degree-of-freedom drive device according to claim 4 or (c), the space is formed so that the distance from the outer periphery of the spherical portion is constant. Freedom drive. By doing so, the measurement accuracy of the rotational position of the rotor can be made uniform.

(E) In the multiple-degree-of-freedom drive device described in the above (d), the space is formed in an arc shape whose cross section in the pressing contact direction is centered on the center of the spherical portion. Freedom drive. This makes it possible to obtain the effect (d) while reducing the amount of the conductive viscous fluid.

[0074]

As described in detail above, according to the present invention,
It is possible to provide a multiple-degree-of-freedom drive device capable of measuring a tilt position of an output shaft, a driven member, and the like provided on a rotor that rotates about a plurality of axes while enabling a simple wiring structure.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a multiple-degree-of-freedom drive device according to a first embodiment.

FIG. 2 is a schematic diagram illustrating a detection terminal according to the first embodiment.

FIG. 3 is a schematic diagram of a multiple-degree-of-freedom drive device according to the first embodiment.

FIG. 4 is a schematic view of a multiple-degree-of-freedom drive device according to a second embodiment.

FIG. 5 is a schematic diagram illustrating a detection terminal according to a second embodiment.

FIG. 6 is a schematic diagram of a multiple-degree-of-freedom drive device according to a second embodiment.

FIG. 7 is a schematic view of another example of a multiple-degree-of-freedom drive device.

[Explanation of symbols]

1, 31 ... case 2, ... stator, 3, 32, 66 ... rotor, 13, 34, 62 ... spherical part, 16, 36 ... capacitance variable part, 21, 41 ... detection terminal, 37 ... space, 38 ...
Conductive viscous fluid, 61: magnetic force variable portion, 6b: contact portion, S
1, S2: capacitance sensor; S3: magnetic sensor.

Claims (5)

[Claims] A contact portion (6b) is provided.
b) a stator (2) that generates vibrations in a plurality of directions; and a spherical portion (13, 34) formed in a substantially spherical shape, and the spherical portion (13, 34) is attached to the contact portion (6b). A rotor (3, 32) that is in pressure contact with the rotor (3, 32), and is capable of rotating the rotor (3, 32) about a plurality of axes based on vibrations in a plurality of directions generated by the stator (2). In the degree drive device, the spherical portion (13, 34) of the rotor (3, 32)
Provided with a capacitance variable section (16, 36) in which the capacitance at a terminal arranged at a predetermined position changes in accordance with its own rotation, and measures the capacitance at the predetermined position. A multiple-degree-of-freedom drive device comprising capacitance sensors (S1, S2). 2. The multi-degree-of-freedom driving device according to claim 1, wherein the spherical portion (1) holds the stator (2) and holds the stator (2).
(3, 34) so as to be rotatable, and a case (1, 3) for substantially accommodating the stator (2) and the spherical portion (13, 34).
1), wherein a detection terminal (21, 41) constituting a part of the capacitance sensor (S1, S1) is accommodated in the case (1, 31). . 3. The multiple-degree-of-freedom drive device according to claim 1, wherein the variable capacitance unit (16) is provided in a band along the outer periphery of the spherical portion (13), The detection terminal (21) constituting a part of the sensor (S1) is connected to the spherical portion (13) and the stator (2).
And a plurality of rows are provided in the circumferential direction with the pressing contact direction with the axis as the center, and are fixed to the stator (2) around the spherical portion (13) so as to be provided in a plurality of rows in the pressing contact direction. Multiple degrees of freedom drive. 4. The multiple-degree-of-freedom drive device according to claim 1, wherein the capacitance variable section (36) forms a space (37) inside the spherical section (34), and the space is formed. (37) is filled with a conductive viscous fluid (38) smaller than the volume of the space (37), and the detection terminal (41) constituting a part of the capacitance sensor (S2) is set at a basic position. The spherical portion (34) and the stator (2) are fixed to the outer periphery of the spherical portion (34) so as to be provided in a plurality in the circumferential direction around the axis of the pressing contact direction of the stator (2) and to be provided in a plurality of rows in the pressing contact direction. A multi-degree-of-freedom drive device characterized by the following. 5. A contact portion (6b) having a contact portion (6b).
b) a stator (2) that generates vibrations in a plurality of directions; and a spherical portion (62) formed in a substantially spherical shape, and the spherical portion (62) is pressed against the contact portion (6b). A rotor (66), the rotor (6) being based on vibrations in a plurality of directions generated by the stator (2).
6) A multi-degree-of-freedom drive device that rotates about a plurality of axes, wherein the spherical portion (62) of the rotor (66) has a magnetic force variable in which a magnetic force at a predetermined position changes according to its own rotation. A magnetic sensor (S3) for measuring a magnetic force at the predetermined position;
A multi-degree-of-freedom drive device characterized by comprising: