JP2011182625A - Rotary drive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary drive which can obtain large output torque with a small-sized and light-weight structure, is excellent in durability, preferable in controllability of an output rotation speed, and is simple in the design concept of the output torque. <P>SOLUTION: The rotary drive includes: a first member (a rotor 3) having a first counter surface (a cylinder inner circumferential surface 31) on a part of the surface, and rotatable around the axial line of a rotary shaft; a second member (a stator 2) having a second counter surface (a cylinder outer circumferential surface 21) remotely facing the first counter surface 31; a plurality of press-contact elastic members (leaf springs 4) erected in one of the first counter surface 31 and the second counter surface 21, declined in the same direction to the rotating direction of the first member 3 and press-contacted to the other of the first and the second counter surfaces 31, 21, and having elasticity; a base 5 rotatably supporting the first member 3 around the axial line AX of the rotating shaft, and regulating the rotation of the second member 2 to support it; and a vibrating means 6 arranged between the second member 2 and the base 5 to vibrate the second member 2 for repeatedly and minutely displacing the separating distance W between the first counter surface 31 and the second counter surface 21. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rotary drive device that outputs torque, and more particularly to a rotary drive device that uses vibration generated by a vibrating means such as a piezoelectric body.

  Motors that use electromagnetic force are generally used as drive devices that convert electric power into mechanical power and output it, but drive devices built into electronic devices and precision machines are particularly compact and highly accurate in position control. Is needed. In response to such demands for miniaturization and high accuracy, a drive device of another drive method using ultrasonic vibration or the like is being put into practical use regardless of electromagnetic force.

  For example, an ultrasonic motor disclosed in Patent Document 1 includes a stator that is excited by a piezoelectric body to generate a traveling wave on a surface, and a rotor that is in contact with the stator and relatively movable. At least one of the stator and the rotor is supported by a thin disc that elastically deforms. When a high-frequency voltage is applied to the piezoelectric body, a traveling wave is generated in the stator by bending vibration, and the rotor in pressure contact is rotated.

  In addition, the ultrasonic linear motor disclosed in Patent Document 2 includes a vibrating body having at least two legs extending from the trunk, and a direction provided on the vibrating body and intersecting at least one of the trunk and the legs. A piezoelectric element is illustrated as the vibration element. Then, by applying a voltage to the piezoelectric element, the tip of the leg rotates in an elliptical shape, and the vibrating body moves on the rail. Thereby, it is said that energy conversion efficiency is high, high-speed operation can be performed, and an extremely compact configuration can be achieved.

  Furthermore, the mechanism including the ultrasonic lead screw motor of Patent Document 3 includes a threaded shaft and a threaded nut, and the threaded nut is subjected to ultrasonic vibration, thereby moving in the axial direction while rotating the threaded shaft. An optical assembly is disclosed. A piezoelectric tube is disclosed as a means for generating ultrasonic vibration. The object of the present invention is to have a substantially higher efficiency than the prior art and to provide high accuracy, great force and speed.

JP-A-62-77068 Japanese Patent Laid-Open No. 2-266881 JP 2008-510445 A

  By the way, the techniques disclosed in the above three patent documents have problems in that the driving force and the propulsive force are limited, and the durability is lowered due to wear of the friction surface. In Patent Document 1, the stator and the rotor are in pressure contact with the opposing surfaces, but the deformation force of the piezoelectric body in the pressing direction is small, and therefore only a small driving force can be obtained. Moreover, when the surface in press contact is rough, the performance is degraded. The same applies to Patent Document 2, and driving is performed while pressing the tip of the leg of the vibrating body against the rail. Therefore, only a propulsive force corresponding to friction due to surface contact can be obtained, and there is a concern about wear of the tip of the leg and the rail. In Patent Document 3, the threaded shaft and the threaded nut rub against each other on the threaded surface and the shaft rotates due to the frictional force, so that a propulsive force greater than the frictional force cannot be obtained.

  The present invention has been made in view of the above-mentioned problems of the background art, and is small and light, can provide a large output torque, is excellent in durability, has excellent controllability of the output rotation speed, and is easy to design the output torque. Providing a rotary drive device is a problem to be solved.

According to a first aspect of the present invention, there is provided a rotary drive device comprising: a first member having a first opposing surface on a part of a surface thereof, and being rotatable about a rotation axis; and being spaced apart from the first opposing surface. And a second member having a second opposing surface facing each other and one surface of the first opposing surface and the second opposing surface, and inclined in the same direction with respect to the rotational direction of the first member. A plurality of pressure contact elastic members that are in pressure contact with the other surfaces of the first facing surface and the second facing surface and have elasticity; and the first member is rotatably supported about the rotation axis; A base that regulates and supports rotation of the member, and is disposed between the first member and the base or between the second member and the base, and the first member or the second member And a vibration means that vibrates and repeatedly fluctuates the separation distance between the first facing surface and the second facing surface. It is characterized by that.

  According to a second aspect of the present invention, in the first aspect, one of the first opposing surface of the first member and the second opposing surface of the second member is a cylindrical inner peripheral surface, and the other is a cylindrical outer peripheral surface. The plurality of pressure contact elastic members erected on one of the inner circumferential surface of the cylinder and the outer circumferential surface of the cylinder are inclined in the same direction in the circumferential direction with respect to the rotation direction of the first member. The base is in pressure contact with the other surface of the peripheral surface and the outer peripheral surface of the cylinder, and the base supports the first member to be rotatable about the rotation axis, and the second member is in a direction perpendicular to the rotation axis. The rotation is controlled so as to be able to vibrate, and the vibration means is arranged between the second member and the base and vibrates the second member in a direction perpendicular to the rotation axis. It is characterized by.

  According to a third aspect of the present invention, in the first aspect, the first opposing surface of the first member and the second opposing surface of the second member are circular planes or ring-shaped planes arranged orthogonal to the rotation axis. The plurality of pressure contact elastic members erected on the one surface are inclined in the same direction in the rotation axis direction with respect to the rotation direction of the first member and are pressed against the other surface, and the base is The first member is supported so as to be rotatable around the rotation axis and vibrated in the direction of the rotation axis, and the rotation of the second member is regulated and supported. The excitation means includes the base and the first It arrange | positions between members and vibrates the said 1st member to the said axial direction, It is characterized by the above-mentioned.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the exciting means is a piezoelectric body.

  The invention according to claim 5 is the plate spring according to any one of claims 1 to 4, wherein the pressure contact elastic member is a leaf spring having a width in the rotation axis direction or the radial direction of the first member. To do.

  The invention according to claim 6 is characterized in that the pressure contact elastic member is a linear spring made of a thin wire having elasticity.

  The invention according to a seventh aspect is the invention according to any one of the first to sixth aspects, wherein an inclination angle at which the pressure contact elastic member is in pressure contact with the other surface is 45 ° with respect to a tangent at a pressure contact position on the other surface. It is characterized by being.

  In the rotary drive device according to the first aspect, the first member having the first facing surface is rotatably supported, and the second member having the second facing surface is supported by restricting rotation. The plurality of pressure contact elastic members are erected on one of the opposing first and second opposing surfaces, are inclined in the same direction with respect to the rotation direction of the first member, and are pressed against the other surface, and Has elasticity. For this reason, when the vibration means vibrates the first member or the second member, the separation distance between the first facing surface and the second facing surface repeatedly varies minutely, and the plurality of pressure contact elastic members also repeats minute elastic deformation. And the driving force which presses the other surface in the direction of the inclination angle is generated. Since this driving force is aligned in the same rotational direction by a plurality of pressure contact elastic members, the first member is rotationally driven to output torque.

  Unlike the conventional driving method in which the driving side and the driven side exemplified in Patent Documents 1 to 3 are in frictional contact with each other, the present invention obtains torque by repeating minute elastic deformation of a plurality of pressure contact elastic members. The method is used. Therefore, by increasing the quantity and elastic strength of the pressure contact elastic member, a large output torque can be obtained even if it is small and light. In addition, since the apparatus configuration is simple and there is no surface that is always in frictional contact, it is not easily affected by roughness and the like, so that it has excellent durability. Further, the output rotation speed can be freely adjusted by controlling the vibration frequency of the vibration means, and the controllability is good. In addition, the magnitude of the torque can be adjusted by increasing or decreasing the number and the elastic strength of the pressure contact elastic member, and the design of the output torque is simple. In addition, since a complicated traveling wave is not used for the drive electric signal for driving the vibration means, the drive power supply unit can be reduced in size and cost.

  In the invention according to claim 2, one of the first opposing surface of the first member and the second opposing surface of the second member is a cylindrical inner peripheral surface, and the other is a cylindrical outer peripheral surface, and the cylindrical inner peripheral surface and the cylindrical outer peripheral surface A pressure-contact elastic member erected on one surface of the inner wall is inclined in the circumferential direction and press-contacted to the other surface. Thereby, it is possible to configure a rotary drive device in which the drive side and the driven side are arranged on the coaxial inner side and the outer side, and it is possible to realize a thin device having a small size in the rotation axis direction.

  In the invention which concerns on Claim 3, the 1st opposing surface of a 1st member and the 2nd opposing surface of a 2nd member are made into the circular plane or cyclic | annular plane arrange | positioned orthogonally to a rotating shaft, and press-contacting standingly arranged in one surface The elastic member is inclined in the rotation axis direction and is in pressure contact with the other surface, whereby a rotation drive device in which the drive side and the driven side are arranged side by side in the rotation axis direction can be configured.

  In the invention which concerns on Claim 4, the vibration means is made into the piezoelectric material. The piezoelectric body can generate vibration from a relatively low frequency region to a high ultrasonic region, and has a wide control range of the output rotation speed.

  In the invention according to claim 5, the pressure contact elastic member is a leaf spring. In the invention according to claim 6, the pressure contact elastic member is a linear spring. By using a leaf spring or a linear spring, the design of quantity and elastic strength can be easily changed, and the magnitude of the output torque can be freely adjusted, and the cost is low because it is a general-purpose member.

  In the invention which concerns on Claim 7, the inclination angle which a press-contact elastic member press-contacts to the other surface is 45 degrees. By setting the angle to 45 °, the efficiency of the pressure contact elastic member converting the vibration force / displacement into the rotation direction is improved, and a large output torque can be obtained.

It is a front view which illustrates typically the rotation drive device of a 1st embodiment of the present invention. It is a figure explaining the shape of the rotor of 1st Embodiment, and a leaf | plate spring, (1) is a rotor, (2) is a leaf | plate spring, (3) is each perspective view of another leaf | plate spring. It is a front view explaining the structure of the rotor and leaf | plate spring of 2nd Embodiment. It is a front view explaining the rotation drive device of a 3rd embodiment typically. It is a side view which illustrates typically the rotation drive device of a 4th embodiment. It is a perspective view explaining the rotor in FIG.

  A rotary drive device according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a front view schematically illustrating a rotary drive device 1 according to a first embodiment of the present invention. As shown in the figure, the rotary drive device 1 is composed of a stator 2, a rotor 3, a leaf spring 4, a base 5, a vibration device 6, and the like.

  The stator 2 is a member on the outer peripheral side corresponding to the second member, and is an outer frame of the rotary drive device 1. A cylindrical inner peripheral surface 21 having an inner diameter D1 corresponding to the second facing surface is formed in the stator 2 in the horizontal direction. The surface of the cylindrical inner peripheral surface 21 is a rough surface, and the friction when the leaf spring 4 comes into pressure contact increases, so that a pressing force is generated without slipping. The rotor 3 spaced apart from the cylindrical inner peripheral surface 21 of the stator 2 is an inner peripheral member corresponding to the first member, and a cylindrical outer peripheral surface 31 having an outer diameter D2 corresponding to the first opposing surface. Are formed in the horizontal direction. A shaft hole is formed at the center of the rotor 3, and an output shaft 35 is fitted in the shaft hole. A load (not shown) can be coupled to the output shaft 35 that rotates integrally with the rotor 3.

  The stator 2 and the rotor 3 are disposed outside the same axis while sharing the horizontal rotation axis AX. Therefore, a cylindrical space S is formed between the cylindrical inner peripheral surface 21 of the stator 2 and the cylindrical outer peripheral surface 31 of the rotor 3, and the radial width W of the space S, that is, the separation distance W, is the both peripheral surfaces 21, 31. (W = (D1−D2) ÷ 2).

  The plurality of leaf springs 4 are disposed in the space S, are erected radially outward from the cylindrical outer peripheral surface 31 of the rotor 3, and are inclined in the same direction in the circumferential direction on the cylindrical inner peripheral surface 21 of the stator 2. It is in pressure contact and has elasticity, and corresponds to a pressure contact elastic member. More specifically, the plurality of leaf springs 4 have a width in the rotation axis AX direction (the front and back direction in FIG. 1), and are erected vertically outward from the cylindrical outer peripheral surface 31 in the radial direction. The leaf spring 4 is refracted in the clockwise direction in the figure in the middle of the outward radial direction. By this refraction, the tip 4X of the leaf spring 4 is in pressure contact with the tangent at the pressure contact position of the cylindrical inner peripheral surface 21 at an inclination angle A = 45 °. The leaf spring 4 can be formed of an elastic metal or resin. In FIG. 1, 28 leaf springs 4 are arranged at equal intervals in the circumferential direction, and the number and elastic strength can be appropriately changed.

  The base 5 supports the stator 2 so that the stator 2 can vibrate and regulate its rotation, and supports the rotor 3 so as to be rotatable about the rotation axis AX. More specifically, the base 5 is composed of a plate-like rigid body, and supports the stator 2 via a buffer material 51 on the upper surface thereof. The buffer material 51 is formed of, for example, synthetic rubber, and allows vibration in the vertical direction perpendicular to the rotation axis AX of the stator 2 to restrict rotation. The base 5 is provided with a bearing (not shown). The bearing supports the output shaft 35 rotatably, and also supports the rotor 3 integrated with the output shaft 35.

  The vibration device 6 is disposed in parallel with the buffer material 51 between the stator 2 and the base 5. The vibration device 6 is a device using a piezoelectric body as a drive source, and is deformed by applying a voltage to the piezoelectric body to vibrate the stator 2 in the vertical direction.

  Next, a structure in which the leaf spring 4 is erected on the rotor 3 will be described. FIGS. 2A and 2B are diagrams for explaining the shapes of the rotor 3 and the leaf spring 4. FIG. 2A is a perspective view of the rotor 3, FIG. 2B is a leaf spring 41, and FIG. As shown in FIG. 2A, 28 slits 32 are formed on the cylindrical outer peripheral surface 31 of the rotor 3 at equal intervals in the circumferential direction and extending radially inward and over a thickness T in the rotation axis AX direction. Has been. Further, as shown in FIG. 2B, the leaf spring 41 is formed by bending a middle part of an elastic metal body having a width corresponding to the thickness T of the rotor 3. The base portion 41Y of the leaf spring 41 can be erected by being inserted and fixed in the slit 32 of the rotor 3.

  In FIG. 2 (1), only one standing leaf spring 41 is indicated by a broken line, and the leaf spring 41 is erected in all the slits 32. At this time, the diameter D3 of the envelope cylindrical surface connecting the tips 41X of all the leaf springs 41 is slightly larger than the inner diameter D1 of the cylindrical inner peripheral surface 21 of the stator 2. Therefore, when the rotor 3 is assembled to the stator 2, the leaf spring 41 is bent and inserted while rotating the rotor 3 counterclockwise in FIG. Thereby, each tip 41X of the leaf spring 41 is assembled in a state where it is pressed against the cylindrical inner peripheral surface 21 at an inclination angle A = 45 °. The leaf spring 41 may be another leaf spring 42 shown in FIG. The other leaf spring 42 is formed by bending an elastic metal body in the middle instead of refraction.

  Furthermore, the rotor 30 and the leaf | plate spring 43 of 2nd Embodiment shown by FIG. 3 can also be used. In 2nd Embodiment, the structure of the stator 2, the base 5, and the vibration exciting apparatus 6 is the same as 1st Embodiment, and the rotor 30 and the leaf | plate spring 43 differ. FIG. 3 is a front view illustrating the structure of the rotor 30 and the leaf spring 43 according to the second embodiment. As shown in the figure, in the second embodiment, a slit 34 is formed on the cylindrical outer peripheral surface 33 of the rotor 30 so as to be inclined inward in the radial direction. In addition, a flat elastic metal body having a width corresponding to the thickness of the rotor 30 is used for the plate spring 43. The flat leaf spring 43 can be erected by inserting and fixing it into the inclined slit 34. At this time, the diameter D4 of the envelope cylindrical surface connecting the tips 43X of the leaf spring 43 is slightly larger than the inner diameter D1 of the cylindrical inner peripheral surface 21 of the stator 2 as in the first embodiment. . Similarly, the leaf spring 43 is bent and inserted into the stator 2 while rotating the rotor 30, and the point 43X of the leaf spring 43 is in pressure contact with the cylindrical inner peripheral surface 21 at an inclination angle A = 45 °. It is.

  Next, the operation and action of the rotary drive device 1 of the first embodiment will be described, and the second embodiment will be omitted because it is substantially the same operation and action. In the first embodiment of FIG. 1, by applying an AC voltage to the piezoelectric body of the vibration device 6, the vibration device 6 is repeatedly deformed to vibrate the stator 2 in the vertical direction. Then, the separation distance W between the stator 2 and the rotor 3 repeats and slightly fluctuates, and minute vibrations propagate to the leaf spring 4. The leaf spring 4 expands and contracts, and the tip 4X instantaneously jumps up from the cylindrical inner peripheral surface 21 and presses against the cylindrical inner peripheral surface 21 again. During the spring-up and pressure contact, a driving force F (shown at one place in FIG. 1) that presses the cylindrical inner peripheral surface 21 in the inclined direction is generated. Since this driving force F is aligned in the same rotational direction in all the leaf springs 4, the rotor 3 is rotationally driven counterclockwise in FIG. Thereby, the output shaft 35 integral with the rotor 3 rotates to output torque to the load.

  Here, since the inclination angle A = 45 ° where the leaf spring 4 is pressed against the cylindrical inner peripheral surface 21 is large, a large driving force F is obtained, and torque can be output efficiently. When the voltage applied to the piezoelectric body is increased, the amount of deformation of the vibration device 6 is increased, the vibration of the stator 2 and the leaf spring 4 is increased, and the output rotational speed and output torque of the rotor 3 are increased. Further, if the voltage frequency is increased, the number of deformations of the vibration device 6 is increased, the number of vibrations of the stator 2 and the leaf springs 4, 41, 42 is increased, and the output rotational speed of the rotor 3 is increased.

  In the first and second embodiments, unlike the conventional driving method in which the driving side and the driven side are in frictional contact with each other, the driving that obtains torque by repeating the minute elastic deformation of the leaf springs 4, 41, 42, and 43. The method is used. Therefore, by increasing the quantity and elastic strength of the leaf springs 4, 41, 42, 43, a large output torque can be obtained even if it is small and light. In particular, a thin device in which the thickness T of the rotor 3 is reduced can be realized. In addition, since the apparatus configuration is simple and there is no surface that is always in frictional contact, it is not easily affected by roughness and the like, so that it has excellent durability.

  Furthermore, since the rotational speed can be freely adjusted by controlling the voltage frequency applied to the piezoelectric body of the vibration device 6, the controllability of the output rotational speed is good. Further, the magnitude of the torque can be adjusted by increasing or decreasing the number of the leaf springs 4 or the elastic strength, and the design of the output torque is simple. In addition, the piezoelectric body can generate vibration from a relatively low frequency region to a high ultrasonic region, and has a wide control range of output rotation speed. Furthermore, since the leaf springs 4, 41, 42, 43 are general general-purpose members, the cost is reduced. In addition, since the AC voltage for driving the excitation device 6 may be a general rectangular wave or sine wave and does not use a complicated traveling wave, the drive power supply unit can be reduced in size and cost.

  In the first and second embodiments, the leaf springs 4, 41, 42, 43 that are pressure contact elastic members are erected on the rotors 3, 30 on the inner peripheral side, but are not limited thereto. That is, a leaf spring which is erected inward in the radial direction from the cylindrical inner peripheral surface 21 of the stator 2 on the outer peripheral side, is in pressure contact with the cylindrical outer peripheral surface 31 of the rotor 3 while being inclined in the same direction in the circumferential direction. can do. Further, the leaf springs 4, 41, 42, 43 can be replaced by metal or resin linear springs made of thin elastic wires. In either aspect, the operation and action are the same as in the first embodiment.

  Further, the roles of the rotor and the stator can be exchanged between the second member on the outer peripheral side and the first member on the inner peripheral side. That is, contrary to the first and second embodiments, the first member is rotatably supported as a rotor on the outer peripheral side, and the second member is vibrated as a stator on the inner peripheral side so as to be able to vibrate and support, The second member on the inner peripheral side can be vibrated to output torque from the first member on the outer peripheral side.

  Next, a rotary drive device 10 according to a third embodiment having a different stator structure will be described with reference to FIG. FIG. 4 is a front view schematically illustrating the rotary drive device 10 of the third embodiment. As shown in the figure, in the third embodiment, the stator 20 is configured by arranging an upper inner peripheral surface 22 and a lower inner peripheral surface 23 having a circular arc cross section above and below the rotor 3, and the other configuration is the first configuration. This is the same as the embodiment. Even in the configuration in which the second facing surface is a part of the inner circumferential surface of the cylinder, the leaf spring 4 is brought into contact with and separated from the vertical movement of the stator 20, so that the same effect as in the first embodiment is produced.

  Next, the rotational drive device 11 of 4th Embodiment is demonstrated with reference to FIG. 5 and FIG. FIG. 5 is a side view schematically illustrating the rotary drive device 11 of the fourth embodiment. As shown in the figure, the rotation drive device 11 is composed of a rotor 7, a leaf spring 45, a case 8, a vibration device 60, and the like. FIG. 6 is a perspective view illustrating the rotor 7 in FIG.

  The rotor 7 is a member corresponding to the first member, and is formed of a disk-shaped member as shown in FIG. A shaft hole 71 is formed in the central portion of the rotor 7 in the direction of the rotation axis AY, and an output shaft 79 that rotates integrally is fitted into the shaft hole 71. One annular plane 72 orthogonal to the rotational axis AY on the surface of the rotor 7 corresponds to the first opposing surface, and a plurality (12 in the example of FIG. 6) of leaf springs 45 are erected on the annular plane 72. Yes. The plurality of leaf springs 45 are provided with a width in the radial direction of the annular plane 72 of the rotor 7 and are inclined in the same direction in the rotation axis AY direction at an inclination angle B = 45 °. The plurality of leaf springs 45 have elasticity and correspond to pressure contact elastic members. The leaf spring 45 can be formed of, for example, stainless steel, and the number and elastic strength thereof can be changed as appropriate.

  The case 8 corresponds to a base and is an outer frame of the rotation drive device 11. As shown in FIG. 5, a fixed seat 82 is provided substantially at the center of the ceiling surface 81 inside the case 8, and a buffer spring 83 is fixed downward below the fixed seat 82. Further, the vibration exciter 60 is fixed to the lower end of the buffer spring 83. The vibration device 60 is formed by a disc-shaped upper plate 61 and lower plate 62 and a laminated piezoelectric body 63 disposed between the upper plate 61 and the lower plate 62. The upper plate 61 is fixed to the buffer spring 83, and the lower plate 62 is in contact with the rotor 7. The thickness of the laminated piezoelectric body 63 of the vibration exciter 60 is changed by applying a voltage, and the distance D5 between the upper plate 61 and the lower plate 62 is increased or decreased.

  An output hole 85 is formed in the approximate center of the bottom surface 84 of the case 8. Between the bottom surface 84 of the case 8 and the vibration device 60, the rotor 7 with the leaf spring 45 facing downward is disposed. The output shaft 79 of the rotor 7 protrudes from the output hole 85 to the outside of the case 8 so that a load (not shown) can be coupled. On the other hand, the other annular plane 73 on which the leaf spring 45 of the rotor 7 is not erected is directed upward and is in contact with the lower plate 62 of the vibration device 60. A bearing member 74 is annularly arranged between the other annular plane 73 of the rotor 7 and the lower plate 62 of the vibration device 60, so that the rotor 7 is rotatable. That is, the rotor 7 is supported by the case 7 so as to be rotatable around the rotation axis AY. The above-described buffer spring 83 urges the rotor 7 downward while allowing vibration in the vertical direction via the vibration device 60 so that the leaf spring 45 is surely pressed against the bottom surface 84 of the case 8. It has become.

  As shown in FIG. 5, the leaf spring 45 of the rotor 7 is in pressure contact with the bottom surface 84 of the case 8 at an inclination angle C = 45 °. The bottom surface 84 of the case 8 acts as a second opposing surface of the second member that is supported by restricting rotation.

  Next, the operation and action of the rotary drive device 11 of the fourth embodiment will be described. In FIG. 5, by applying an AC voltage to the laminated piezoelectric body 63 of the vibration device 60, the distance D5 between the upper plate 61 and the lower plate 62 of the vibration device 60 is increased or decreased to move the rotor 7 in the vertical direction. Shake. Then, the separation distance W2 between one annular flat surface 72 (first opposing surface) of the rotor 7 and the bottom surface 83 (second opposing surface) of the case 8 repeatedly varies minutely, and minute vibrations propagate to the leaf spring 45 as well. . The leaf spring 45 expands and contracts, and the tip 45X instantaneously jumps up from the bottom surface 84 and presses against the bottom surface 84 again. During the spring-up and pressure contact, a driving force F2 (shown at one place in FIG. 4) that presses the bottom surface 84 in the inclined direction is generated. Since the driving force F2 is uniform in the same rotational direction in all the leaf springs 45, the rotor 7 is rotationally driven by the reaction force. As a result, the output shaft 79 integral with the rotor 7 rotates to output torque to the load.

  Here, since the inclination angle C at which the leaf spring 45 is pressed against the bottom surface 84 is 45 °, a large driving force F2 can be obtained and torque can be output efficiently. When the voltage applied to the laminated piezoelectric body 62 is increased, the amount of deformation of the vibration device 60 is increased, the vertical vibration of the rotor 7 is increased, and the output rotation speed and output torque are increased. Further, if the frequency of the voltage is increased, the number of deformations of the vibration device 60 increases, the number of vibrations of the rotor 7 increases, and the output rotation speed increases. Furthermore, since the laminated piezoelectric body 62 has a large number of piezoelectric elements laminated in series, it is easy to obtain a large amount of deformation.

  Therefore, as in the first to third embodiments, a large output torque can be obtained even if it is small and lightweight. In addition, since the apparatus configuration is simple and there is no surface that is always in frictional contact, it is not easily affected by roughness and the like, so that it has excellent durability. Further, the controllability of the output rotation speed is good, the design of the output torque is simple, and the cost is low.

  In addition, the shape of the 1st and 2nd opposing surface is not limited to the shape of 1st-4th embodiment, For example, it can also be made into a cone-shaped surface. In addition to the piezoelectric body, a magnetostrictive body that generates distortion when an electric current is applied, or a polymer resin that generates distortion due to movement of internal electrons when a voltage is applied, are used as a driving source for the vibration devices 6 and 60. be able to. The present invention can be applied in various other ways.

DESCRIPTION OF SYMBOLS 1, 10, 11: Rotation drive device 2, 20: Stator (2nd member) 21: Cylindrical inner peripheral surface (2nd opposing surface)
22: Upper inner peripheral surface 23: Lower inner peripheral surface 3, 30: Rotor (first member) 31, 33: Cylindrical outer peripheral surface (first opposing surface)
32, 34: slit 35: output shaft 4, 41, 42, 43, 45: leaf spring (pressure contact elastic member)
4X, 41X, 43X, 45X: tip
41Y: Root part 5: Base 51: Buffer material 6, 60: Excitation device (excitation means) 61: Upper plate 62: Lower plate 63: Laminated piezoelectric material 7: Rotor (first member) 71: Shaft hole 72 : One ring-shaped plane (first facing surface)
73: The other annular plane 74: Bearing member 79: Output shaft 8: Case (base) 81: Ceiling surface 82: Fixed seat 83: Buffer spring
84: Bottom surface (second opposing surface of the second member) 85: Output hole AX, AY: Rotation axis A, B, C: Inclination angle F, F2: Driving force W, W2: Separation distance

Claims (7)

A first member having a first opposing surface on a part of the surface and rotatable about a rotation axis;
A second member having a second facing surface that is spaced apart from and faces the first facing surface;
One of the first facing surface and the second facing surface is erected on one surface, and is inclined in the same direction with respect to the rotation direction of the first member, and is in the first facing surface and the second facing surface. A plurality of pressure contact elastic members that are in pressure contact with the other surface and have elasticity;
A base that supports the first member so as to be rotatable about the rotation axis, and supports the second member by restricting rotation;
Between the first member and the base or between the second member and the base, the first member or the second member is vibrated to vibrate the first opposing surface and the second Vibration means for repeatedly changing the separation distance from the opposing surface by minute fluctuations;
A rotary drive device comprising: In claim 1, one of the first opposing surface of the first member and the second opposing surface of the second member is a cylindrical inner peripheral surface, the other is a cylindrical outer peripheral surface,
The plurality of pressure contact elastic members erected on one of the inner circumferential surface of the cylinder and the outer circumferential surface of the cylinder are inclined in the same direction in the circumferential direction with respect to the rotation direction of the first member. The other surface of the surface and the outer peripheral surface of the cylinder,
The base supports the first member so as to be rotatable around the rotation axis, and supports the second member by restricting rotation so that the second member can vibrate in a direction perpendicular to the rotation axis.
The vibration means is disposed between the second member and the base and vibrates the second member in a direction perpendicular to the rotation axis.
A rotary drive device characterized by that. The first opposing surface of the first member and the second opposing surface of the second member according to claim 1 are a circular plane or an annular plane arranged orthogonal to the rotation axis.
The plurality of pressure contact elastic members erected on the one surface are inclined in the same direction in the rotation axis direction with respect to the rotation direction of the first member and are pressed against the other surface,
The base supports the first member so that the first member can rotate about the rotation axis and can vibrate in the direction of the rotation axis, and supports the rotation of the second member by restricting the rotation.
The vibration means is disposed between the base and the first member and vibrates the first member in the axial direction.
A rotary drive device characterized by that.   The rotation driving device according to claim 1, wherein the excitation unit is a piezoelectric body.   5. The rotation drive device according to claim 1, wherein the pressure-contact elastic member is a leaf spring having a width in the rotation axis direction or the radial direction of the first member.   5. The rotary drive device according to claim 1, wherein the pressure contact elastic member is a linear spring made of an elastic thin wire.   7. The rotational drive according to claim 1, wherein an inclination angle at which the pressure contact elastic member is pressed against the other surface is 45 ° with respect to a tangent at a pressure contact position on the other surface. apparatus.

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