JPH01238470A - Directly driving device - Google Patents

Abstract

PURPOSE:To operate a directly driving device in a high accuracy at a high speed by forming the device in a quadrangular prismlike structure, providing piezoelectric elements deformed in a thicknesswise direction at respective edges, and providing four-branching elastic cutouts and a slide member. CONSTITUTION:A directly driving device is composed by providing a base 1 of a quadrangular prismlike bottom having a square-shaped bottom, thicknesswise displacing piezoelectric elements 2a-2d of the same size at respective edges, elastic cutouts 3 at the ends of the elements opposite to the base 1, and a driving end 4 made of a slide member at the top of the quadrangular prism. Since the moving locus of the end 4 generated by the displacements of the elements 2a-3d has displacement components of all directions of the heightwise direction of the device and the planar direction parallel to the face of the base, a member to be driven can be moved by a frictional force by pressing the member parallel to the face of the base to a driving end 5.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a direct drive device using a piezoelectric material that is capable of highly efficient electrical/mechanical energy conversion, and is particularly applicable to devices that require high-speed and high-precision positioning. The present invention relates to a direct drive device suitable for driving joint shafts of a direct drive robot.

[Conventional technology]

Conventional direct drive devices and rotary drive devices are: 1) Japanese Patent Publication No. 5
No. 9-30912 discloses a device in which a tilted vibrating piece is pressed against a disk surface at a high frequency, the disk is struck by the force generated by the bending deformation, and the disk is driven by frictional force. 2) Japanese Patent Laid-Open No. 60-62880 discloses a device in which an inclined vibrating piece and a disk 1 are integrally formed, and the torsional vibration of the disk 1 is transmitted to the disk 2 through surface contact. In addition, as described in 3) Japanese Patent Application Laid-Open No. 60-200776, which is not part of the present application, a pair of piezoelectric bodies are arranged obliquely on a base, and an elastic member is provided at each tip to combine the displacement of each voltage body, A device was shown in which a sliding member provided at the tip of the device contacts and drives a driven body.

In addition, conventional direct drive robots, for example,
As shown in No. 3875, an electromagnetic direct drive motor was used.

[Problem to be solved by the invention]

Regarding the direct drive device and the rotary drive device, the above-mentioned prior art 1) generates force while hitting the disk surface with an inclined vibrating piece, which has the problem of damaging the surface and causing severe wear. Furthermore, in order to change the moving direction of the driven body, two rows of inclined vibrating element rows and disks must be provided to perform an interchanging operation, which poses a problem of complicating the mechanism. Furthermore, although prior art 2) improves the wear problem of prior art 1) by making surface contact between the disks, it has the problem that the mechanism for moving the driven body in the forward and reverse directions becomes complicated. . Conventional technology 3) has the advantage of being able to electrically move the driven body in forward and reverse directions using two piezoelectric bodies, and the problem of wear is between 1) and 2). All of the above three conventional technologies are configured to obtain the movement of the driven body in one direction, so in order to drive the driven body at low speed, a low voltage must be applied to the piezoelectric body, which causes There was a problem that the power also decreased0
SUMMARY OF THE INVENTION An object of the present invention is to provide a rotary drive device that can generate low speed and high torque using a direct drive device that can be displaced in two directions.

In addition, the conventional technology related to direct drive robots uses an electromagnetic direct drive motor, which does not have a sufficient output/self-weight ratio, and the second arm is driven from the base of the first arm via a steel belt. A further object of the present invention is to eliminate the use of direct drive motors that do not take full advantage of their advantages.
The object of the present invention is to construct a lightweight joint drive device using the above-mentioned direct drive device and rotary drive device, and provide a direct drive robot capable of high-speed, high-precision movement by directly attaching the joint drive device to each joint.

[Means to solve the problem]

The above purpose of the direct drive device is to form the direct drive device into a square pyramid-shaped structure, provide a piezoelectric body that deforms in the thickness direction on each ridgeline, and change the displacement of three other piezoelectric bodies on the top side of the square pyramid of each piezoelectric body. This is achieved by providing a four-pronged elastic cutout having a degree of freedom in the direction and providing a sliding member at the tip thereof.

The above object of the rotary drive device is to configure the direct drive device so that the bottom surface of the square pyramid is square, and to set the fixed body so that the diagonal direction of the bottom surface of the square pyramid is radial and circumferential with respect to the rotation axis. This is achieved by arranging the direct drive in such a way that the sliding member of the direct drive is pressed against the disk surface and by arranging the direct drive in a radially slidable and circumferentially restrained manner on the fixed body.

The above object with respect to a direct drive robot is achieved by directly integrating the rotary drive and the direct drive into the joint axis and wrist axis of the robot.

[Effect]

The operation of the direct drive device will be explained. The thickness direction displacement piezoelectric body can move the thickness direction displacement by applying a voltage between the electrodes provided facing each other in the thickness direction.The 8 direct drive device applies the thickness direction displacement piezoelectric body to each ridgeline of the square pyramid shape. is provided so that its displacement direction coincides with the ridge line direction,
An elastic notch is provided on the top side of the square pyramid, and this has a degree of freedom in the displacement direction of three piezoelectric bodies other than each piezoelectric body on the top side of the square pyramid of each piezoelectric body. The sliding member applies a frictional movement force in any direction on the contact plane of the driven body. The notch is equivalent to a circular pair in two orthogonal directions, and is rigid in the planar direction of the pair, but is flexible and has a degree of freedom in the plane direction perpendicular to the pair, so it is difficult to see the piezoelectric body from two directions. It becomes possible to synthesize displacements. When a piezoelectric body is directly driven at the resonant frequency of the drive device, a larger vibration displacement is obtained in the sliding member than when driven at other frequencies even with the same applied voltage, and the driven body can be moved with a large force. The operation of the six-order rotary drive device that enables this will be explained. The fixed body is provided with a linear guide part in the radial direction, and the direct drive device is slidable in the radial direction, and a disc part (
(rotating body). Direct drives can be moved to any radial position.

It can be stopped in the radial direction by frictional force at a predetermined position.

By frictionally driving the disk portion in the circumferential direction at this position, rotation of the output shaft is obtained. Assuming that the voltage applied to the piezoelectric body is the same and there is no slippage in the friction drive unit, the same force and speed can be transmitted to the moving body, so if the direct drive unit is located at a large radius position, the output shaft Low speed and high torque characteristics can be obtained, and when the direct drive device is located at a small radius position, high speed and low torque characteristics can be obtained at the output shaft. Since the radial position of the direct drive device can be set arbitrarily, continuously variable speed operation can be realized by setting and controlling the radial position detector.

Next, the operation of the direct drive robot will be explained.

Direct drive robots have each joint axis (rotation axis or linear axis)
The rotary shaft is driven by the above-mentioned rotary drive device, and for the joint axes that require linear motion, linear motion can be achieved by using a direct drive device that can drive the driven body in one direction by frictional contact. [Example] The present invention will be described in detail below. An embodiment of the direct drive device will be described with reference to FIGS. 1 to 6. FIG. 1 is a perspective view of the direct drive device of the present invention. A base 1 is provided at the bottom of a square pyramid with a square base, and piezoelectric bodies 28 to 2d with the same dimensions in the thickness direction are provided on each ridge line, and an elastic cut is provided at the end opposite to the base of the piezoelectric bodies 2a to 2d. A notch 3 is provided and a drive end 4 made of a sliding member is provided at the top of the square pyramid.The arrows shown in the piezoelectric bodies 28 to 2d in FIG. An example of the movement locus of the drive end 4 caused by the displacement of the piezoelectric bodies 2a to 2d is shown. Drive end 4
Since the trajectory of has a displacement component in both the height direction of the direct drive device and the plane direction parallel to the base surface, by pressing the driven body against the drive end 5 parallel to the base surface, the driven body The body can be moved using frictional force.

Next, details of the structure of the present direct drive device will be explained using FIGS. 2 to 5. FIG. 2 is a vertical sectional view taken along the line A-B in FIG. 1. In the illustrated example, the angle formed by the longitudinal directions of the piezoelectric bodies 2b and 2d is 90°, and the configuration is such that interference between the piezoelectric bodies is reduced when the piezoelectric bodies are driven. In the illustrated example, the angle formed by the longitudinal direction of 2a and 2c is also 90°. Each of the piezoelectric bodies 2a to 2d is tightened between the base elastic notches 3 by bolts 6a to 6d. This is because piezoelectric ceramics, which are the material of piezoelectric bodies, have strong compressive strength but weak tensile strength, so by applying compressive force in advance, it is possible to prevent performance deterioration of piezoelectric ceramics even during large amplitude vibrations. It has the advantage of being possible. In addition, since the resonant frequency of the direct drive device seen from the piezoelectric body changes depending on the tightening force of the piezoelectric body, when driving the piezoelectric body at the resonant frequency, there may be slight variations in performance among the four piezoelectric bodies. This also has the advantage that the resonant frequency can be adjusted by adjusting the bolt tightening force. FIG. 3 shows an example of the structure of the piezoelectric body 2 that is displaced in the thickness direction (large arrow in the figure). This piezoelectric body has a structure in which piezoelectric ceramic thin plates with opposite polarization directions (small arrows in the figure) are laminated via electrodes, and when voltage is applied to the ° terminal, all piezoelectric ceramic thin plates either expand or contract in the thickness direction in the same way. indicating displacement,
There is a through hole in the center of the piezoelectric body 2, which is used when fastening bolts. FIGS. 4 and 5 show examples of notches provided at the ends of each piezoelectric body 2 of one elastic notch 3. FIG. In this direct drive device, the notch is used for transmitting force in the axial direction and receives loads from two directions in the plane.
A mechanism that has high rigidity in the axial direction and can be displaced in two directions in the plane is required, and by having a double link configuration in each direction as shown in the figure, it is possible to avoid problems. Therefore, four hakama parts are provided, and the notch elements include a method in which the entire outer periphery on both sides of the restraint part is cut out, and a method in which notches are provided in two directions on both sides of the guard part, respectively, as shown in Figures 4 and 5. It was shown to. When moving a driven object at high speed and with a large force, it is highly efficient to drive the piezoelectric body at the resonant frequency of a direct drive device that has a vibration mode that provides a large displacement in the direction of movement of the driven object at the drive end. .

The locus of the drive end in that case will be explained using FIG. 6. The piezoelectric bodies 2a, 2c (not shown) and the notches provided at their ends are perpendicular to the displacement direction of the piezoelectric bodies 2b, 2d. Therefore, since almost no displacement occurs when voltage is applied to the piezoelectric bodies 2b and 2d, the explanation will be given here within a plane that includes the piezoelectric bodies 2b and 2d. When the piezoelectric body 2b is driven at the resonant frequency, a locus as shown by the broken line 5b is obtained at the drive end 4, and the driven body 7 is moved in the direction 8b due to the difference in frictional force when reciprocating with respect to the driven body 7. When the piezoelectric body 2d is driven at the resonant frequency, a locus as shown by the broken line 5d is obtained at the drive end 4, and the driven body 7 is moved in the direction 8d. A similar phenomenon is observed when the piezoelectric bodies 2a and 2c are each driven at a resonant frequency. From the above, the direct drive device of the present invention has the advantage that it can move the driven body in each direction at high speed by driving the piezoelectric body in each direction independently at the resonance frequency.

Next, an embodiment of a rotary drive device using the direct drive device of the present invention will be described with reference to FIGS. 7 to 1.0.

Cylindrical rotating body rotation wi! The motion device will be explained using FIGS. 71Δ to 9. FIG. 7 shows a longitudinal section of the inner cylinder rotary drive device. Direct drive device 1 for clarity in the diagram
The area around 0 is shown without taking a cross section. FIG. 8 shows a cross section along line C-D and section along line E-F in FIG. 7.

It is shown in Figure 9. The structure and operation of the rotary drive device will be explained using FIG. 7. Direct drive device IQa.

10b denotes linear guide blocks 20a and 20 that are movable in the radial direction on the linear guides lla and llb that are radially provided on the fixed plate bottom plates 17a and 17C.
b is coupled to h1 so that the displacement directions of the piezoelectric body are in the radial direction and the circumferential direction. Direct drive device 10a, 10
b is the bearing 13.b relative to the fixed body 17. ．． The drive ends are pressed against the surfaces of disks 16a, 16b which are connected to a rotating body 15 which is rotatably supported via 1-4. Direct drive drive end and disk 16a.

16b is made of a combination of materials with a large coefficient of friction and a small amount of wear. When pressing the disk with the direct drive device, the most efficient drive can be achieved by selecting an appropriate value for the force. The rotation axis of a position detector 19 for detecting the rotational position of the zero rotation body 15 with respect to the fixed body 17, which can be adjusted by tightening, is connected to the zero rotation axis of the rotation body 15 through a coupling 18. , the operation of this rotary drive device will be explained. Direct drive devices 10a, 10b are based on bases 17a, 17
It is movable in the radial direction with respect to c, but is restrained in one circumferential direction. Furthermore, since the rotating body 15 is restrained in the radial direction and rotatable in the circumferential direction, the piezoelectric bodies 2b, 2d' or 2d, 2b' are driven at a resonant frequency by a direct drive device. 10a and 10b can move at high speed in the large radial direction or the small radial direction on the linear guides lla and llb. When the voltage application to the piezoelectric bodies 2b, 2d, 2d', and 2b' is stopped at a certain radial position, the frictional force causes the direct drive device 10a.

10b is locked in its radial position. Therefore, if the piezoelectric bodies 2a, 2a' or 2c, 2c' are driven at the resonant frequency, the direct drive device], Oa, 10b is the disk 16.
a and 16b are contact-driven in both circumferential directions. Piezoelectric body 2
When the voltage application to a, 2a', 2c, and 2c' is stopped, the rotating body 15 is locked in that position.The 8-piece rotary drive device is locked in the radial direction of rotation by frictional force when no voltage is applied to the piezoelectric body. This has the advantage of eliminating the need for mechanical brakes. The advantages of a radially moving scale with a direct drive are discussed below.

A direct drive device applies an alternating voltage of the same amplitude to the piezoelectric body at its resonant frequency and produces the same force at the drive end.

Generates the same vibration speed. Therefore, the circumferential direction 'wAll
Regarding No. 13, low speed and large torque can be generated at the same applied voltage at the large radius position, and high speed and low torque can be generated at the small radius position. Therefore, there is an advantage that the load can be driven by selecting optimal conditions depending on the application. Further, although FIG. 7 shows a system in which the disk is sandwiched between two direct drive devices, it is also possible to drive the disk from one side using one direct drive device. However, although the former is larger than the latter, it has the advantage of reliable contact between the direct drive device and the disk and high torque. In addition, in FIG. 7, a pair of direct drive devices 10a are provided in the circumferential direction of the base ]-7.

10b is provided, but it is also possible to increase the output torque by multiple times by providing a plurality of pairs.

Next, we will discuss the peripheral parts such as the detector of this rotary drive device in the 8th section.
This will be explained using FIGS. As described above, the rotational position of the rotating body 15 can be detected by the position detector 19. The radial position of the direct drive device is configured to detect the absolute position using both the position detector 22 and the low contact switches 24 and 25. When performing a radial movement, it is first necessary to perform a return-to-origin operation. The procedure for returning to the origin is shown in Figure 1Q.

First, the origin sensor 24b is used to detect whether the current initial position is above or below the origin W (the detection position (indicated by a circle) of the origin sensor 24b in FIG. 9). In FIG. 9, 24a and 24c are proximity switches for overrun detection, and beyond this position, the direct drive device f10
When a moves, it collides with stoppers 1.2a and 12b and comes to rest. Therefore, by configuring so that 08≧Q1, the origin sensor is not covered by the dog 23a when the direct drive device is above the origin position, and is not covered when it is below, making it difficult to determine the area. This makes it possible to detect the origin position at the boundary. In this example, the reference signal generation position W 27 a of the position detector 22a is provided slightly below the origin position. Therefore, when the dog 23a descends, the origin sensor 24b detects the position (origin position) at which the covered state changes to the uncovered state, and when the dog 23a descends further from that position, the reference borrowed sign occurrence position
The position detector detects t 27 a and stops when the voltage application is stopped at that position.Since the reference signal generation position of the 0 position detector has been detected, the relative position from this position can then be detected using the position detector 22a. By detecting this, the absolute radial direction of the direct drive device can be determined.

Although the above description has been made regarding one side of the pair of direct drive devices, the absolute position in the radial direction can also be detected using the same procedure on the opposite side.

Next, an example of an external cylinder rotating body type rotation drive device is shown in FIG.

11b and a linear guide block 20a.

Drives 10a, 10b are directly coupled to 20b. The drive end of the direct drive device 10a and iob is the rotating body 15
Discs 1.6a, 16c provided on the inner surface of a, 15c
is being forced to. The principle of operation is the same as that of the inner cylinder rotating body type, and the detector is also equipped with the same detector as shown in FIGS. 8 and 9 for the inner cylinder rotating body type. Even in the case of using the outer rotor shape, if the radius of contact of the direct drive device with the disk is the same as that of the inner rotor shape, the generated torque is the same. The rotary drive device can be mounted in either an inner cylinder rotating body type or an outer cylinder rotating body type depending on the shape of the member, etc., and the rotating body can be used as a fixed body, and the fixed body can be used as a rotating body.

Next, an example of a direct drive robot using the direct drive device and rotary drive device of the present invention will be explained with reference to FIGS. 12 to 14. Before that, an example of a direct drive robot using a conventional electromagnetic direct drive motor will be explained using FIG. 15, and its characteristics and drawbacks will be clarified. Most of the horizontal long joint type direct drive robots currently used for assembly work that requires high speed and high precision have a first arm 30. The second arm 31 is driven by a direct drive motor, but current electromagnetic direct drive motors cannot drive the wrist shaft with a very high output/self-weight ratio, making it heavy and increasing the load. A torque motor is used, and its output is slowed down via a speed reducer and a ball screw. FIG. 15 shows an example.

Direct part! l! Since the IJ electric motor generates a large torque, if a mechanical brake 38 is provided to ensure safety, a large brake capacity is required, and the brake 38b
has the disadvantage that it becomes a large load on the direct drive motor 37a. In addition, the wrist mechanism also includes a reducer with a 41° ball screw and a 39° ball screw. The mechanism is complicated due to the use of a timing belt, etc., and the rigidity in the operating direction is not very high. It is known that the maximum output/self-weight ratio is about three times higher than that of other devices (see Mechanical Design Vol. 31, No. 13 (1987), p. 56), and all axes including the wrist axis can be When driven by the above device, the weight of the drive device is reduced, and since there is a braking function using static friction force when no voltage is applied, it is not necessary to install a mechanical brake, making it possible to further reduce the weight. FIG. 12 shows an example in which each axis drive device of a direct drive robot equivalent to FIG. 15 is replaced with a direct drive device and a rotary drive device. 1st arm 3
The above-mentioned rotary drive device was used to drive the 0 and second arms 31. A rotation drive device for driving the first arm [a fan 29a was provided below 28a. This prevents changes in performance and performance deterioration due to heat generation of the piezoelectric body, making it possible to maintain highly efficient driving. The wrist shaft drive mechanism at the tip of the second arm 31 will be explained. Output # (spline shaft) 3
A hand 36 is provided at the tip of 5. The spline shaft 35 is supported by the second arm 31 via the spline bearing 34, the mounting member 42, and a rolling bearing. A disk 33 is coupled to the spline bearing mounting member 42, and the disk 33 is pressed with a nut to a direct drive device that supports the disk 33 so as to be movable in the radial direction at its lower part, thereby forming a rotary drive bag [128c]. ing. Rotational position detection is performed using a position detector (e.g. brushless resolver)
A piezoelectric drive device shown in FIG. 13 is built into the cylinder 40 connected to the zero-spline bearing mounting portion 42 at 19c. This piezoelectric drive device has two direct drive devices of the present invention.
This allows for dimensional driving, whereas it allows for one-dimensional driving. The GH section plane is shown in Fig. 14.

The driving ends of the piezoelectric drive devices 10a' to 10c' are in three-point contact with the side surface of the spline shaft 35, and the pressing force can be adjusted by bolts and nuts 43a to 43c.

The spline shaft 35 is moved in the vertical direction by a direct drive device 28d constituted by the piezoelectric drive devices 10a' to 10c'.
It has the same structure as shown in the figure, and a spline bearing mounting member 42 is provided on the plate 32 coupled to the cylindrical body 40.

A direct drive robot using a direct drive device and rotary drive device with this configuration has a lighter joint drive device, lighter weight due to the removal of brakes, and movement of each axis compared to a direct drive robot using a conventional electromagnetic direct drive motor. It has the advantage of being able to achieve high rigidity in the direction.

〔Effect of the invention〕

According to the present invention, it is possible to move a driven body in two directions with one direct drive device using a piezoelectric body with a large output self-weight ratio, and the direct drive device is configured to be able to slide in the radial direction. The drive device allows a rotary drive device that has speed-torque characteristics that match the load size and required characteristics to move around, so the joint drive device of a direct drive robot can be moved using the above-mentioned direct drive device and rotary drive device. By configuring this structure, the weight of the joint drive device can be reduced, the weight of the joint can be reduced by eliminating the brake, and the direct drive robot can be driven at high speed, with high precision, and with high efficiency.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the direct drive device of the present invention, and Fig. 2 is a perspective view of the direct drive device of the present invention.
3 is a perspective view of the piezoelectric body, 4th
5 is a perspective view of the elastic notch, FIG. 6 is an explanatory diagram of the operation of the direct drive device, FIG. 7 is a longitudinal sectional view of the internal cylinder rotary body rotary drive device of the present invention, and FIG. 8 is the 7 is a vertical cross-sectional view of section C-D, FIG. 9 is a longitudinal cross-sectional view of section E-F of FIG. A vertical cross-sectional view of the body rotation drive device,
FIG. 12 is a vertical sectional view of the direct drive robot of the present invention, the first
FIG. 3 is a structural diagram of a unidirectionally moving piezoelectric drive device, FIG. 14 is a cross-sectional view of section G-H in FIG. 12, and FIG. 15 is a longitudinal sectional view of a conventional direct drive robot. 1...Base, 2...Thickness direction displacement piezoelectric body, 3...
- Elastic notch, 4... Drive end, 5... Drive end displacement direction, 6... Bolt, 7... Driven body, 8...
・・Direction of movement of driven body, 9 ・Direction of displacement of piezoelectric body, 10
... Direct drive device, 11... Linear guide, 12.
... Stopper, 13.14... Bearing, 15... Rotating body, 16... Disc, 17... Fixed body, 18...
...Coupling, 19...Position detector, 20...
Linear guide block, 21... Code plate, 22...
・Position detector, 23...Dog, 24.25...Proximity switch, 26...Volt, 27...Reference signal generation position, 28a, 28b, 28c...Rotary drive device, 2
8d... Direct drive device, 29... Fan, 30...
・First arm, 31... Second arm, 32... Board,
33...Disc, 34...Spline bearing, 35
...Spline shaft, 36...Hand, 37a. 37b...Direct drive electric motor, 37c, 37d...High speed/low torque electric motor, 38...Brake, 39...Ball screw, 40...Cylinder 541...Reducer, 42...
... Spline bearing mounting member, 43... Bolts and nuts. Ne lI21 ￥14-I1218sC 6, -1, °") Reto No. 6 Mouth--Base"--9 ・--l Moni 9 Hosei 2 Shibai IL71i Yufu 3
Ku Li 10 Figure 1 ¥) If Figure

Claims (1)

[Claims] 1. A plurality of piezoelectric bodies, an elastic notch that combines the displacements of the piezoelectric bodies when a voltage is applied, and a sliding member provided at the tip of the elastic notch that allows the driven body to contact and move. In the direct drive device having a member, the direct drive device has a square pyramidal structure, the bottom surface serves as a base, and the displacement direction of the four piezoelectric bodies that are displaced in the thickness direction coincides with the ridgeline of the square pyramidal structure. one end of the piezoelectric body is fixed to the base, and the other end of each of the piezoelectric bodies is connected to a four-pronged elastic cutout having a degree of freedom in the direction of displacement of the other three piezoelectric bodies,
A direct drive device characterized in that a sliding member is provided at the top of the square pyramid at the tip of the elastic notch. 2. In a rotary drive device using a direct drive device according to claim 1, the direct drive device is a fixed body (or a rotating body), and the rotary body (or the fixed body)
The piezoelectric body is press-fitted with a disk unit coupled to the disk unit, so that the direction of displacement of the pair of piezoelectric bodies provided on the diagonal ridge lines of the square pyramid of the direct drive device coincides with the circumferential direction of the disk unit. and the other pair of piezoelectric bodies are provided so that their displacement direction coincides with the radial direction of the disk portion, and the direct drive device is arranged in a radial direction with respect to the fixed body (or rotating body) on which it is installed. 1. A rotary drive device, wherein the rotary drive device is slidably supported and restrained in a circumferential direction, and the rotating body and the fixed body are rotatably supported via a bearing.