JP4804163B2 - Ultrasonic motor - Google Patents

Description

  The present invention relates to an ultrasonic motor, and more particularly to an ultrasonic motor that rotates a rotor in an arbitrary direction by a plurality of stators.

  Conventionally, development of an ultrasonic motor capable of moving a rotor in contact with a stator by vibration of a piezoelectric element on the stator side without using a magnetic force has progressed.

  Ultrasonic motors can be used in various applications by devising the number of stators and the shape of the rotor. For example, disk-type and ring-type rotors are already well known, and recently, a spherical super rotor with a rotor as a sphere. Development of sonic motors is also progressing.

  For example, in the invention described in Patent Document 1, a rotor that is a sphere is held in three directions by the three stators so that the entire circumference of each annular surface of the three stators is in contact with the rotor. The rotor is rotated in an arbitrary direction by controlling the rotation direction of the individual stators.

JP-A-11-84526

  In this way, ultrasonic motors of various shapes have been proposed in the past, but taking advantage of the ultrasonic motor that it can be used even when the surrounding is magnetized, the field of application of ultrasonic motors has been improved. In order to further expand, it is desired to further reduce the size and weight of the ultrasonic motor.

  The present invention has been made in view of the above points, and an object of the present invention is to provide an ultrasonic motor that is reduced in size and weight while ensuring a plurality of degrees of freedom.

  The present invention includes a rotor and a ring-shaped vibrator that excites a traveling wave on a ring by a piezoelectric body, and a first ring-shaped vibrator, a second ring-shaped vibrator around the rotor, In the ultrasonic motor in which the third ring-shaped vibrator and the fourth ring-shaped vibrator are arranged and brought into pressure contact, the first ring-shaped vibrator is provided at one end and the second ring vibrator is provided at the other end. A first frame member provided with a ring-shaped vibrator, and a second frame member provided with the third ring-shaped vibrator at one end and the fourth ring-shaped vibrator at the other end, The first frame member and the second frame member are provided so as to intersect each other with the rotor interposed therebetween.

  According to the present invention, in the invention described in claim 1, the shape of the rotor is a cube.

  In the invention according to claim 2, the present invention is characterized in that a concave portion into which each ring-shaped vibrator is fitted is provided on a surface of each surface of the rotor, which is in contact with each ring-shaped vibrator. And

  The present invention also includes a rotor and a ring-shaped vibrator that excites a traveling wave on an annulus using a piezoelectric body, and a first ring-shaped vibrator and a second ring-shaped vibrator around the rotor. The first frame member having the first ring-shaped vibrator provided at one end and the first shaft rod provided at the other end, and the first frame member provided at the one end with 2 ring-shaped vibrators and a second frame member provided with a second shaft rod at the other end, and each shaft of each surface of the rotor is opposed to the surface facing each shaft rod. An insertion hole into which a rod is inserted is provided, and the first frame member and the second frame member are provided in a direction crossing the rotor.

  In the invention according to claim 4, the rotor is a sphere.

  The present invention also includes a rotor and a ring-shaped vibrator that excites a traveling wave on an annulus using a piezoelectric body, and a first ring-shaped vibrator and a second ring-shaped vibrator around the rotor. The first frame member having the first ring-like vibrator provided at one end and the first disc provided at the other end, and the first frame member provided at the other end. And a second frame member provided with a second disk at the other end, and the shape of the rotor is a cube, and each ring of each surface of the rotor A concave portion for fitting each ring-shaped vibrator is provided on a surface that contacts the circular vibrator, and a concave portion for fitting each disk is provided on a surface of each surface of the rotor that contacts each circular disk. The first frame member and the second frame member are provided so as to cross each other with the rotor interposed therebetween.

  In the invention according to any one of claims 1 to 6, the present invention is characterized in that a position detection device for detecting a relative position between each ring-shaped vibrator and the rotor is provided. .

  ADVANTAGE OF THE INVENTION According to this invention, the ultrasonic motor which implement | achieved size reduction and weight reduction, ensuring a some freedom degree can be provided.

  That is, according to the present invention, one degree of freedom is realized by the frame member and the rotor, and one degree of freedom is realized by another frame member and the rotor, so that the center of rotation is established between the frame members via the rotor. Two identical degrees of freedom can be realized.

  In addition, according to the present invention, since the rotational position detection device is provided to detect the relative position between the frame member and the rotor, desired operation control can be performed.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view schematically showing an ultrasonic motor according to an embodiment of the present invention.

  As shown in FIG. 1, the ultrasonic motor 1 according to the present embodiment rotates a cubic rotor 2 held by two stators 3a and 3b, and further held by two stators 6a and 6b. Rotate.

  A large number of vibrating pieces 13 a are provided on the surface of the stator 3 a that contacts the rotor 2, and a large number of vibrating pieces 13 b are provided on the surface of the stator 3 b that contacts the rotor 2, and the vibrating pieces 13 a and 13 b vibrate. Generates traveling waves.

  Further, a recess 2a is provided on the surface of the rotor 2 that contacts the stator 3a. The stator 3a is fitted into the recess 2a, and the recess 2a is also provided on the surface of the rotor 2 that contacts the stator 3b. The stator 3b is configured to fit into 2a.

  The vibrating piece 13a of the stator 3a and the vibrating piece 13b of the stator 3b are in contact with the rotor 2, and the rotor 2 is rotated by a traveling wave generated by the vibration of the vibrating piece 13a and the vibrating piece 13b.

  The stator 3a is fixed to one end of a U-shaped frame member 4 by a stopper 4a such as a screw, and the stator 3b is fixed to the other end of the frame member 4 by a stopper 4b such as a screw, so that the rotor 2 is appropriately strengthened. Hold it like this. At this time, as described above, the stator 3a and the stator 3b are fitted in the recess 2a of the rotor 2, so that the stator 3a and the stator 3b are not displaced from the rotor 2.

  On the other hand, a large number of vibrating pieces 16a are provided on the surface of the stator 6a that contacts the rotor 2, and a large number of vibrating pieces 16b are provided on the surface of the stator 6b that contacts the rotor 2, and these vibrating pieces 16a and 16b vibrate. And generate a traveling wave.

  A recess 2a is provided on the surface of the rotor 2 that contacts the stator 6a. The stator 6a is fitted into the recess 2a, and the recess 2a is also provided on the surface of the rotor 2 that contacts the stator 6b. The stator 6b is fitted to 2a.

  The vibrating piece 16a of the stator 6a and the vibrating piece 16b of the stator 6b are in contact with the rotor 2, and the rotor 2 is rotated by a traveling wave generated by the vibration of the vibrating piece 16a and the vibrating piece 16b.

  The stator 6a is fixed to one end of a U-shaped frame member 7 by a stopper 7a such as a screw, and the stator 6b is fixed to the other end of the frame member 7 by a stopper 7b such as a screw. Hold it like this. At this time, as described above, the stator 6a and the stator 6b are fitted into the concave portion 2a of the rotor 2 so that the stator 6a and the stator 6b are not displaced from the rotor 2.

  As shown in FIG. 1, the frame member 4 and the frame member 7 are provided in a direction that intersects with the rotor 2 interposed therebetween.

  FIG. 2 is a side view of the ultrasonic motor 1 shown in FIG. 1 viewed from the direction II in FIG.

  FIG. 3 is a side view of the ultrasonic motor 1 shown in FIG. 1 viewed from the direction III of FIG.

  FIG. 4 is a plan view of the ultrasonic motor 1 shown in FIG. 1 as viewed from the direction IV of FIG.

  FIG. 5 is a bottom view of the ultrasonic motor 1 shown in FIG. 1 viewed from the direction V of FIG.

  In the ultrasonic motor 1 according to the present embodiment, by using the stators 6a and 6b to generate traveling waves in the same direction in the stator 6a and the stator 6b, the frame member 7 in the direction of the arrow M shown in FIG. And the rotor 2 can be rotated relatively, and by using the stators 3a and 3b to generate traveling waves in the same direction in the stator 3a and the stator 3b, the direction of the arrow P shown in FIG. The frame member 4 and the rotor 2 can be rotated relatively.

  According to the present embodiment, the frame member 4 and the rotor 2 realize one degree of freedom, and the frame member 7 and the rotor 2 realize one degree of freedom. With the frame member 7, two degrees of freedom can be realized.

  FIG. 6 is a perspective view schematically showing an ultrasonic motor according to the second embodiment of the present invention.

  As shown in FIG. 6, the ultrasonic motor 101 according to the present embodiment rotates a cubic rotor 102 by holding it with a stator 103a and a shaft rod 103b, and further holding it with a stator 106b and a shaft rod 106a. Rotate.

  A large number of vibrating pieces 113a are provided on the surface of the stator 103a in contact with the rotor 102, and the vibrating pieces 113a vibrate to generate traveling waves.

  Further, a recess 102a is provided on the surface of the rotor 102 that contacts the stator 103a, and the stator 103a is configured to fit into the recess 102a. On the other hand, an insertion hole 102b is provided on the surface of the rotor 102 facing the shaft rod 103b. The shaft rod 103b is inserted into the insertion hole 102b, and the insertion hole 102b and the shaft rod 103b are slidable. Yes.

  The vibrating piece 113a of the stator 103a is in contact with the rotor 102, and the rotor 102 is rotated by a traveling wave generated by the vibration of the vibrating piece 113a.

  The stator 103a is fixed to one end of a U-shaped frame member 104 by a stopper 104a such as a screw, and the shaft rod 103b is fixed to the other end of the frame member 104 by a stopper 104b such as a screw. Hold as if pressing with strength. At this time, as described above, the stator 103a fits into the recess 102a of the rotor 102 and the shaft rod 103b is inserted into the insertion hole 102b of the rotor 102, so that the stator 103a, the shaft rod 103b and the rotor 102 are not displaced. .

  On the other hand, a large number of vibrating pieces 116b are provided on the surface of the stator 106b in contact with the rotor 102, and the vibrating pieces 116b vibrate to generate traveling waves.

  Further, a recess 102a is provided on the surface of the rotor 102 that contacts the stator 106b, and the stator 106b is fitted into the recess 102a. On the other hand, an insertion hole 102b is provided on the surface of the rotor 102 facing the shaft rod 106a. The shaft rod 106a is inserted into the insertion hole 102b, and the insertion hole 102b and the shaft rod 106a are slidable. Yes.

  The vibrating piece 116b of the stator 106b comes into contact with the rotor 102, and the rotor 102 is rotated by a traveling wave generated by the vibration of the vibrating piece 116b.

  The stator 106b is fixed to one end of a U-shaped frame member 107 by a stopper 107b such as a screw, and the shaft rod 106a is fixed to the other end of the frame member 107 by a stopper 107a such as a screw. Hold as if pressing with strength. At this time, as described above, the stator 106b fits into the recess 102a of the rotor 102 and the shaft rod 106a is inserted into the insertion hole 102b of the rotor 102, so that the stator 106b and the shaft rod 106a are not displaced from the rotor 102. .

  As shown in FIG. 6, the frame member 104 and the frame member 107 are provided so as to cross each other with the rotor 102 interposed therebetween.

  According to the present embodiment, the frame member 104 and the rotor 102 achieve one degree of freedom, and the frame member 107 and the rotor 102 realize one degree of freedom. With the frame member 107, two degrees of freedom can be realized.

  FIG. 7 is a perspective view schematically showing an ultrasonic motor according to the third embodiment of the present invention.

  As shown in FIG. 7, the ultrasonic motor 201 according to the present embodiment rotates and rotates a cubic rotor 202 by a stator 203a and a disc 203b, and further holds the rotor by a stator 206b and a disc 206a. Rotate.

  A large number of vibrating pieces 213a are provided on the surface of the stator 203a in contact with the rotor 202, and the vibrating pieces 213a vibrate to generate traveling waves.

  Further, a recess 202a is provided on the surface of the rotor 202 that contacts the stator 203a, and the stator 203a is configured to fit into the recess 202a. On the other hand, a recess 202a is also provided on the surface of the rotor 202 that contacts the disc 203b, and the disc 203b is fitted into the recess 202a, so that the recess 202a and the disc 203b are slidable.

  The vibrating piece 213a of the stator 203a contacts the rotor 202, and the rotor 202 is rotated by a traveling wave generated by the vibration of the vibrating piece 213a.

  The stator 203a is fixed to one end of a U-shaped frame member 204 by a stopper 204a such as a screw, and the disk 203b is fixed to the other end of the frame member 204 by a stopper 204b such as a screw. Hold as if pressing with strength. At this time, as described above, the stator 203a fits into the recess 202a of the rotor 202 and the disc 203b fits into the recess 202a of the rotor 202, so that the stator 203a and disc 203b and the rotor 202 are not displaced.

  On the other hand, a large number of vibrating pieces 216b are provided on the surface of the stator 206b in contact with the rotor 202, and the vibrating pieces 216b vibrate to generate traveling waves.

  Further, a concave portion 202a is provided on the surface of the rotor 202 that contacts the stator 206b, and the stator 206b is configured to fit into the concave portion 202a. On the other hand, a recess 202a is also provided on the surface of the rotor 202 facing the disc 206a. The disc 206a is fitted into the recess 202a, and the recess 202a and the disc 206a are slidable.

  The vibration piece 216b of the stator 206b is in contact with the rotor 202, and the rotor 202 is rotated by a traveling wave generated by vibration of the vibration piece 216b.

  The stator 206b is fixed to one end of a U-shaped frame member 207 by a stopper 207b such as a screw, and the disk 206a is fixed to the other end of the frame member 207 by a stopper 207a such as a screw. Hold as if pressing with strength. At this time, as described above, the stator 206b fits into the recess 202a of the rotor 202, and the disk 206a fits into the recess 202a of the rotor 202, so that the stator 206b, the disk 206a and the rotor 202 are not displaced.

  As shown in FIG. 7, the frame member 204 and the frame member 207 are provided in a direction that intersects with the rotor 202 interposed therebetween.

  According to the present embodiment, the frame member 204 and the rotor 202 achieve one degree of freedom, and the frame member 207 and the rotor 202 realize one degree of freedom. With the frame member 207, two degrees of freedom can be realized.

  FIG. 8 is a perspective view schematically showing an ultrasonic motor according to the fourth embodiment of the present invention.

  As shown in FIG. 8, the ultrasonic motor 301 according to the present embodiment rotates a rotor 302, which is a sphere, by holding it with a stator 303a and a shaft rod 303b, and further holding it with a stator 306b and a shaft rod 306a. Rotate.

  A large number of vibrating pieces 313a are provided on the surface of the stator 303a in contact with the rotor 302, and the vibrating pieces 313a vibrate to generate traveling waves.

  The shape of the surface of the stator 303a that contacts the rotor 302 is a shape that holds the rotor 302 in conformity with the spherical surface of the rotor 302, and the insertion hole 302b is provided on the surface of the rotor 302 that faces the shaft rod 303b. The shaft rod 303b is inserted into the insertion hole 302b, and the insertion hole 302b and the shaft rod 303b are slidable.

  The vibration piece 313a of the stator 303a is in contact with the rotor 302, and the rotor 302 is rotated by a traveling wave generated by the vibration of the vibration piece 313a.

  The stator 303a is fixed to one end of a U-shaped frame member 304 by a stopper 304a such as a screw, and the shaft rod 303b is fixed to the other end of the frame member 304 by a stopper 304b such as a screw. Hold as if pressing with strength. At this time, as described above, the stator 303a holds the rotor 302 and the shaft rod 303b is inserted into the insertion hole 302b of the rotor 302 so that the stator 303a, the shaft rod 303b, and the rotor 302 are not displaced.

  On the other hand, a large number of vibrating pieces 316b are provided on the surface of the stator 306b that contacts the rotor 302, and the vibrating pieces 316b vibrate to generate traveling waves.

  The shape of the surface of the stator 306b that contacts the rotor 302 is a shape that fits the spherical surface of the rotor 302 and holds the rotor 302. The surface of the rotor 302 that faces the shaft rod 306a is provided with an insertion hole 302b. The shaft rod 306a is inserted into the insertion hole 302b, and the insertion hole 302b and the shaft rod 306a are slidable.

  The vibration piece 316b of the stator 306b contacts the rotor 302, and the rotor 302 is rotated by a traveling wave generated by the vibration piece 316b vibrating.

  The stator 306b is fixed to one end of a U-shaped frame member 307 by a stopper 307b such as a screw, and the shaft 306a is fixed to the other end of the frame member 307 by a stopper 307a such as a screw. Hold as if pressing with strength. At this time, as described above, the stator 306b holds the rotor 302 and the shaft rod 306a is inserted into the insertion hole 302b of the rotor 302 so that the stator 306b, the shaft rod 306a and the rotor 302 are not displaced.

  As shown in FIG. 8, the frame member 304 and the frame member 307 are provided in a direction that intersects with the rotor 302 interposed therebetween.

  According to the present embodiment, the frame member 304 and the rotor 302 achieve one degree of freedom, and the frame member 307 and the rotor 302 realize one degree of freedom. With the frame member 307, two degrees of freedom can be realized.

  FIG. 9 is a perspective view schematically showing an ultrasonic motor according to the fifth embodiment of the present invention.

  As shown in FIG. 9, the ultrasonic motor 401 according to the present embodiment rotates a rotor 402, which is a sphere, by holding and rotating it with a stator 403a and a shaft rod 403b, and further holding it with a stator 406b and a shaft rod 406a. Rotate.

  A large number of vibrating pieces 413a are provided on the surface of the stator 403a in contact with the rotor 402, and the vibrating pieces 413a vibrate to generate traveling waves.

  The shape of the surface of the stator 403a that contacts the rotor 402 is a shape that holds the rotor 402 in conformity with the spherical surface of the rotor 402, and an insertion hole 402b is provided on the surface of the rotor 402 that faces the shaft rod 403b. The shaft rod 403b is inserted into the insertion hole 402b, and the insertion hole 402b and the shaft rod 403b are slidable.

  The vibration piece 413a of the stator 403a is in contact with the rotor 402, and the rotor 402 is rotated by a traveling wave generated by the vibration of the vibration piece 413a.

  The stator 403a is fixed to one end of a U-shaped frame member 404 by a stopper 404a such as a screw, and the shaft 403b is fixed to the other end of the frame member 404 by a stopper 404b such as a screw. Hold as if pressing with strength. At this time, as described above, the stator 403a holds the rotor 402 and the shaft rod 403b is inserted into the insertion hole 402b of the rotor 402, so that the stator 403a, the shaft rod 403b, and the rotor 402 are not displaced.

  In the present embodiment, a rotational position detection device 402c is provided in the vicinity of the insertion hole 402b and the shaft rod 403b. The rotational position detection device 402c detects the relative rotational position displacement between the insertion hole 402b and the shaft rod 403b using, for example, an encoder, and can detect the relative position between the frame member 404 and the rotor 402. This detection result is referred to by a control means (not shown) and can be used for operation control of the ultrasonic motor 401. As shown in FIG. 9, the rotational position detection device 402 c may be provided outside the rotor 402, or the rotational position detection device 402 c may be embedded in the rotor 402 by cutting the rotor 402 or the like.

  On the other hand, a large number of vibrating pieces 416b are provided on the surface of the stator 406b in contact with the rotor 402, and the vibrating pieces 416b vibrate to generate traveling waves.

  The shape of the surface of the stator 406b that contacts the rotor 402 is a shape that fits the spherical surface of the rotor 402 and holds the rotor 402, and the surface of the rotor 402 that faces the shaft 406a is provided with an insertion hole 402b. The shaft rod 406a is inserted into the insertion hole 402b, and the insertion hole 402b and the shaft rod 406a are slidable.

  The vibration piece 316b of the stator 306b contacts the rotor 302, and the rotor 302 is rotated by a traveling wave generated by the vibration piece 316b vibrating.

  The stator 406b is fixed to one end of a U-shaped frame member 407 by a stopper 407b such as a screw, and the shaft 406a is fixed to the other end of the frame member 407 by a stopper 407a such as a screw. Hold as if pressing with strength. At this time, as described above, the stator 406b holds the rotor 402 and the shaft rod 406a is inserted into the insertion hole 402b of the rotor 402, so that the stator 406b and the shaft rod 406a are not displaced from the rotor 402.

  In the present embodiment, the rotational position detecting device 402c is also provided in the vicinity of the insertion hole 402b and the shaft rod 406a. The rotational position detection device 402c detects the relative rotational position displacement between the insertion hole 402b and the shaft rod 406a using, for example, an encoder, and can detect the relative position between the frame member 407 and the rotor 402. This detection result is referred to by a control means (not shown) and can be used for operation control of the ultrasonic motor 401.

  As shown in FIG. 9, the frame member 404 and the frame member 407 are provided in a direction intersecting with the rotor 402 interposed therebetween.

  According to the present embodiment, the frame member 404 and the rotor 402 realize one degree of freedom, and the frame member 407 and the rotor 402 realize one degree of freedom. With the frame member 407, two degrees of freedom can be realized.

  Further, according to the present embodiment, the rotational position detection device 402c is provided to detect the relative position between the frame member 404 and the rotor 402 and to detect the relative position between the frame member 407 and the rotor 402. Operation control can be performed.

  In addition, this invention can also be implemented combining each structure of each above-mentioned embodiment arbitrarily.

  In each of the above-described embodiments, the rotor is a cube or a sphere. However, the present invention is not limited to this, and may have any shape.

1 is a perspective view schematically showing an ultrasonic motor according to an embodiment of the present invention. It is the side view which looked at the ultrasonic motor 1 shown in FIG. 1 from the direction II of FIG. It is the side view which looked at the ultrasonic motor 1 shown in FIG. 1 from the direction III of FIG. It is the top view which looked at the ultrasonic motor 1 shown in FIG. 1 from the direction IV of FIG. FIG. 3 is a bottom view of the ultrasonic motor 1 shown in FIG. 1 viewed from a direction V in FIG. 2. It is a perspective view which shows the outline of the ultrasonic motor by the 2nd Embodiment of this invention. It is a perspective view which shows the outline of the ultrasonic motor by the 3rd Embodiment of this invention. It is a perspective view which shows the outline of the ultrasonic motor by the 4th Embodiment of this invention. It is a perspective view which shows the outline of the ultrasonic motor by the 5th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic motor 2 Rotor 3a, 3b, 6a, 6b Stator 13a, 13b, 16a, 16b, Vibrating piece 4, 7 Frame member

Claims (7)

A rotor, and a ring-shaped vibrator that excites a traveling wave on a ring by a piezoelectric body, and a first ring-shaped vibrator, a second ring-shaped vibrator, and a third ring around the rotor In an ultrasonic motor in which a cylindrical vibrator and a fourth ring-shaped vibrator are placed in pressure contact with each other,
A first frame member provided with the first ring-shaped vibrator at one end and the second ring-shaped vibrator at the other end;
A second frame member provided with the third ring-shaped vibrator at one end and the fourth ring-shaped vibrator at the other end;
An ultrasonic motor, wherein the first frame member and the second frame member are provided so as to intersect each other with the rotor interposed therebetween.   The ultrasonic motor according to claim 1, wherein the rotor has a cubic shape.   3. The ultrasonic motor according to claim 2, wherein a concave portion into which each ring-shaped vibrator is fitted is provided on a surface of each surface of the rotor that contacts each of the ring-shaped vibrators. A rotor and a ring-shaped vibrator that excites a traveling wave on a ring by a piezoelectric body, and a first ring-shaped vibrator and a second ring-shaped vibrator are arranged around the rotor to be added In ultrasonic motors that are in pressure contact,
A first frame member provided with the first ring-shaped vibrator at one end and a first shaft bar at the other end;
A second frame member provided with the second ring-shaped vibrator at one end and a second shaft rod at the other end;
An insertion hole into which each shaft rod is inserted is provided on the surface of each surface of the rotor facing each shaft rod,
An ultrasonic motor, wherein the first frame member and the second frame member are provided so as to intersect each other with the rotor interposed therebetween.   The ultrasonic motor according to claim 4, wherein the rotor is a sphere. A rotor and a ring-shaped vibrator that excites a traveling wave on a ring by a piezoelectric body, and a first ring-shaped vibrator and a second ring-shaped vibrator are arranged around the rotor to be added In ultrasonic motors that are in pressure contact,
A first frame member provided with the first ring-shaped vibrator at one end and a first disc at the other end;
A second frame member provided with the second ring-shaped vibrator at one end and a second disk provided at the other end;
The rotor has a cubic shape;
A concave portion into which each ring-shaped vibrator is fitted is provided on a surface of each surface of the rotor in contact with each of the ring-shaped vibrators, and a surface of each surface of the rotor in contact with each of the disks. , A recess into which each of the disks fits is provided,
An ultrasonic motor, wherein the first frame member and the second frame member are provided so as to intersect each other with the rotor interposed therebetween.   The ultrasonic motor according to claim 1, further comprising a position detection device that detects a relative position between each of the ring-shaped vibrators and the rotor.

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