JP2006014498A - Drive unit, guide device, and rotating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive unit which uses a piezoelectric element in a direction a compression stress is applied, regardless of the moving direction of a movable member. <P>SOLUTION: The drive unit 6 comprises a drive piece 61 in which a contact part 64 is provided toward the drive surface 51 provided to a movable member 3 along the moving direction L of the movable member 3 moving relative to a base plate 2, a frame 62 fixed to the base plate 2; and at least two piezoelectric elements 63 which are fitted between the drive piece 61 and the frame 62 in a direction that vectors V1, V2 which are applied with voltage and extend, pass through the drive piece 61 and obliquely cross the drive surface 51. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a driving device using a piezoelectric element as an actuator, a guide device including the driving device, and a rotating device.

  There are driving devices such as a micromotor and a feeding device that are driven by applying a piezoelectric inverse effect in which the piezoelectric element expands and contracts by applying a voltage to the piezoelectric element. In this driving device, an electrode covering substantially the front surface is attached to one surface of a piezoelectric element formed in a rectangular flat plate shape, and four electrodes are arranged in a grid pattern on the other surface. The electrodes arranged at the diagonal positions are electrically connected. The driving device is disposed in a direction in which the electrode surface of the piezoelectric element crosses the axis of the rotating cylindrical body.

  One short edge portion of the outer peripheral portion of the piezoelectric element faces the outer surface of the rotating cylindrical body, and a ceramic spacer is attached thereto. The drive device is in contact with a support and a spring arranged in a direction along the long edge. When the electrode on one diagonal line of the piezoelectric element is energized at a repetition rate of the resonance frequency of the piezoelectric element, the tip of the ceramic spacer draws a circular motion. Using this circular motion, the ceramic spacer moves the rotating cylinder in the circumferential direction. (For example, refer to Patent Document 1).

In addition, there is a feeding device in which two pairs of driving mechanisms are arranged in the moving direction of the movable member and two pairs are arranged in the moving direction. Each drive mechanism includes a clamping piezoelectric element for holding the movable member and a feeding piezoelectric element for moving the movable member. The clamping piezoelectric element is arranged in a direction sandwiching the movable member, and the feeding piezoelectric element is arranged with the expansion / contraction direction aligned with the moving direction of the movable member. This feed mechanism may apply a periodic voltage change having a different waveform to the clamp piezoelectric element and the feed piezoelectric element, or may apply a sinusoidal voltage having a 90 ° phase difference ( For example, refer nonpatent literature 1.).
Japanese Patent Application No. 7-184382 (Fig. 1) Eiji Shamoto and two others, “Development of Precision Feeding Mechanism Using Walking Drive (3rd Report)”, Journal of Precision Optics, 2001, Vol. 67, No. 7, p. 1125-1129

  A drive device in which an electrode is attached to a piezoelectric element formed in a rectangular flat plate shape is pressed against a rotating shaft or a movable member from one direction when used as a drive source such as a motor. Since a frictional resistance is required between the driving device and the movable member, a preload is applied. When the motor is driven, the movable member has a time during which the drive device is not held by the motor due to the case where the drive device is in contact and the case where the drive device is not in contact. Further, since the driving device uses a resonance phenomenon, it is suitable for increasing the moving speed of the movable member, but is not suitable for positioning with high accuracy.

  In addition, a feed mechanism that includes two piezoelectric elements in the drive mechanism, and uses one piezoelectric element for clamping and the other piezoelectric element for feeding is used when the movable member is moved in a certain direction. If compressive stress is applied to the piezoelectric element, tensile force is always applied to the feeding piezoelectric element when the movable member is moved in the opposite direction. Therefore, the feeding piezoelectric element is easily damaged. Although it is easy to provide a driving mechanism corresponding to each moving direction so that only compressive stress is applied to the feeding piezoelectric element, the driving mechanism requires twice as much and half of the driving mechanisms corresponding to the moving direction Since it is only used, it is useless.

  Therefore, the present invention can reduce the influence of preload with a simple structure using a driving device that uses a piezoelectric element in a direction in which a compressive stress is applied regardless of the moving direction of the movable member. An object is to provide a guide device or a rotating device.

  The drive device according to the present invention includes a drive piece provided with a contact portion toward a drive surface provided on the movable member along a moving direction of the movable member moving with respect to the base, and a frame fixed to the base. , And at least two piezoelectric elements attached between the drive piece and the frame in a direction in which a vector in a direction in which a voltage is applied extends obliquely across the drive surface through the drive piece.

  Alternatively, the drive device according to the present invention is arranged in a pair with contact portions facing in opposite directions to a pair of drive surfaces provided in parallel to the movable member along the moving direction of the movable member moving relative to the base. At least one set of drive pieces, at least one set of frames fixed to the base and facing each of the drive faces, and a vector in a direction in which a voltage is applied to extend the drive pieces. And at least two piezoelectric elements attached to each drive piece between the drive piece and the frame in a direction that passes through and obliquely crosses the drive surface. In this case, at least two pairs of drive pieces are arranged side by side in the moving direction of the movable member in order to move the movable member with stable accuracy and speed by pressing the movable member with each drive piece. The pieces are operated with a positional relationship of mirror images with respect to the driving surface, and the driving pieces arranged in the moving direction are operated with a positional relationship shifted from each other.

  In addition, in order to prevent directionality from occurring in the driving force, holding force, and movement stroke depending on the mounting angle of the piezoelectric element, the piezoelectric element is driven from the driving surface by a vector in the direction that expands when a voltage is applied. It arrange | positions in the state inclined to the rotationally symmetrical positional relationship with respect to the perpendicular passing through the contact part of a piece. Alternatively, the piezoelectric element is arranged in a state in which a vector in a direction extending by applying a voltage is inclined to a mirror image positional relationship with respect to a neutral plane passing through the driving piece and perpendicularly crossing the moving direction. A preferable setting range for the angle at which the vector is inclined is 45 ° ± 5 ° with respect to the drive surface.

  In order to obtain a drive device that continuously moves the movable member in one direction, the drive piece is reciprocated by applying different voltage changes to each of the at least two piezoelectric elements. Further, in order to obtain a driving device that moves the movable member at a stable moving speed, the driving piece is periodically reciprocated by applying high-frequency voltages having a phase difference to each of at least two piezoelectric elements. In this case, the frequency of the high frequency voltage is preferably set in a band including the natural frequency of the piezoelectric element.

  Further, in order to move the movable member along the driving surface by one driving device, voltage changes with different phases, amplitudes, and waveforms are applied to at least three piezoelectric elements to displace the driving piece, A control unit is provided that moves in at least two directions intersecting each other along the driving surface.

  The guide device according to the present invention includes a base, a movable member that moves relative to the base, a first member and a second member that move relative to each other, and a plurality of members that are in rolling contact with each other. A guide mechanism having one of the first member and the second member fixed to the base and having the other attached to the movable member, and at least two provided in parallel along the moving direction of the movable member. One friction member, and at least two sets of drive devices arranged in a pair opposite to each other toward the drive surface of the friction member along the moving direction. Each driving device includes a driving piece provided with a contact portion toward the driving surface, a frame fixed to the base, and a vector in a direction in which a voltage is applied to extend the driving surface through the driving piece. And at least two piezoelectric elements attached between the drive piece and the frame in an obliquely transverse direction. By applying a high-frequency voltage having a phase difference to at least two piezoelectric elements, the drive piece is periodically regressed, and the phases of the return movements of the drive pieces provided in the pair of drive devices are synchronized and the same drive The same control is performed by moving the movable member to one side along the moving direction by reversing the phase of the return motion of the drive pieces provided in the different sets of drive devices directed to the surface, and reversing the revolving direction of the return motion. To move the movable member to the other along the moving direction.

  In this case, the driving surface is provided in parallel along the moving direction of the movable member, and the pair of driving devices are arranged on a straight line orthogonal to the moving direction with the driving pieces facing each other. Alternatively, the driving surface is provided in parallel along the moving direction of the movable member, and the pair of driving devices are arranged on a straight line orthogonal to the moving direction with the driving pieces facing away from each other. In order to move the movable member with stable accuracy and speed, a plurality of sets of drive devices are arranged in the moving direction. Alternatively, a plurality of sets of drive devices are arranged in a direction crossing the moving direction.

  The rotating device according to the present invention includes a base, a movable member that rotates relative to the base, a first member and a second member that rotate relative to each other, and a plurality of rolling members that are in rolling contact with each other. A rolling bearing provided with a moving body, wherein one of the first member and the second member is fixed to the base and the other is attached to the movable member, and a friction member provided concentrically with respect to the rotation center line of the movable member And at least two sets of drive devices arranged in pairs opposite to each other on the same line perpendicularly crossing the drive surface formed along the rotation direction of the friction member. Each driving device includes a driving piece provided with a contact portion toward the driving surface, a frame fixed to the base, and a vector in a direction in which a voltage is applied to extend the driving surface through the driving piece. And at least two piezoelectric elements attached between the drive piece and the frame in an obliquely transverse direction. By applying a high-frequency voltage having a phase difference to at least two piezoelectric elements, the drive piece is periodically regressed, and the phases of the return movements of the drive pieces provided in the pair of drive devices are synchronized and the same drive The same control is performed by moving the movable member to one side along the rotational direction by reversing the phase of the return motion of the drive pieces provided in different sets of drive devices directed to the surface, and reversing the revolving direction of the return motion. To move the movable member to the other along the rotation direction.

  In this case, the drive surface is provided perpendicular to the rotation center line of the movable member, and the pair of drive devices are arranged in the direction along the rotation center line in a state where the drive pieces face each other in the direction along the rotation center line. . Alternatively, the drive surface is provided along the outer periphery of the movable member, and the pair of drive devices are arranged on a straight line orthogonal to the rotation center line in a state where the drive piece faces the rotation center line of the movable member. Alternatively, the drive surface is provided along the inner periphery of the movable member, and the pair of drive devices are arranged on a straight line orthogonal to the rotation center line in a state where the drive piece is directed away from the rotation center line of the movable member. . In order to move the movable member with stable accuracy and speed, the rotating device arranges the driving devices in a plurality of pairs in the rotational direction. Alternatively, the rotating device arranges a plurality of driving devices in a direction along the rotation center line of the movable member.

  According to the driving device of the present invention, the piezoelectric element is attached between the driving piece and the frame in such a direction that the vector in the direction in which the voltage is applied extends in an oblique direction across the driving surface through the driving piece. Therefore, the piezoelectric element can be used in the direction in which the compressive stress is applied regardless of the direction in which the movable member is moved. Since the piezoelectric element has a structure in which tensile stress is not positively applied, the durability of the driving device is improved.

  According to another driving device of the present invention, at least one set of a pair of contact portions disposed in a direction opposite to each other on a pair of driving surfaces provided in parallel to the movable member along the moving direction of the movable member. The driving piece, at least one pair of frames arranged in a pair facing each of the pair of driving surfaces, and a vector in a direction in which a voltage is applied and extended so as to cross the driving surface diagonally through the driving piece Piezoelectric elements attached at least two for each driving piece are provided between the driving piece and the frame.

  According to the guide device of the present invention, at least a pair of drive devices are arranged with the drive pieces facing each other in the opposite directions with respect to the drive surface formed along the moving direction of the movable member, and the drive of the pair of drive devices The phase in which the piece regresses is synchronized. Therefore, the forces in the direction crossing the moving direction acting on the movable member by the driving piece are canceled each other, and the positioning accuracy of the movable member is improved. In addition, since the movable member can be held by at least a pair of drive devices even during the movement of the movable member, the moving amount and moving speed of the movable member can be accurately controlled.

  According to the rotating device of the present invention, a pair of driving devices are disposed in the opposite direction on the same line perpendicularly crossing the driving surface formed concentrically with the rotation center line of the movable member, and the pair of driving devices. The phase of the driving piece is reciprocating. Therefore, the force in the direction across the rotational direction acting on the movable member by the drive piece is canceled out, and the force applied to the movable member when the drive device is attached can be reduced. In addition, since the movable member can be held by at least a pair of driving devices even during rotation of the movable member, the rotational position and rotational speed of the movable member can be accurately controlled.

  A guide device 1 according to a first embodiment of the present invention will be described with reference to FIGS. A guide device 1 shown in FIG. 1 includes a base 2, a movable member 3, a guide mechanism 4, a friction member 5, and a drive device 6. The guide mechanism 4 includes a first member 41, a second member 42, and a plurality of rolling elements 43. The first member 41 is fixed to the base 2, and the second member 42 is fixed to the movable member 3. The rolling elements 43 are in rolling contact with raceway grooves 41 a and 42 a formed in the first member 41 and the second member 42, respectively. Accordingly, since the second member 42 moves relative to the first member 41, the movable member 3 moves relative to the base 2. The friction member 5 is attached to both side portions 31 extending along the moving direction L of the movable member 3, and a drive surface 51 is provided in parallel. Note that the friction member 5 may be formed integrally with the side portion 31 of the movable member 3 as long as the drive surface 51 is provided along the moving direction L of the movable member 3.

  As illustrated in FIG. 2, the driving device 6 includes a driving piece 61, a frame 62, and a piezoelectric element 63. The drive piece 61 is provided with a contact portion 64 toward the drive surface 51. The frame 62 is fixed to the base 2. The frame 62 is provided with a recess 62a for arranging the driving piece 61 and an elastic hinge 62b formed in a slit shape so as to surround the recess 62a. The elastic hinge 62b is provided to adjust a force (preload) for extending the piezoelectric element 63 and pressing the driving piece 61 against the driving surface 51. A coil spring, a leaf spring, or a rubber-like elastic member may be attached instead of the elastic hinge 62b.

  Two piezoelectric elements 63 are attached between the drive piece 61 and the frame 62. These piezoelectric elements 63 expand when a voltage is applied. Each piezoelectric element 63 has a direction S in which the vectors V1 and V2 in the extending direction pass obliquely across the drive surface 51 through the drive piece 61 and a perpendicular line S of the drive surface 51 passing through the contact portion 64 of the drive piece 61. On the other hand, it is arranged in a state of being inclined in a rotational symmetry. In this case, since there are two piezoelectric elements 63 in the present embodiment, the piezoelectric element 63 has the vectors V1 and V2 in the direction in which the piezoelectric element 63 expands pass through the contact portion 64 so that the moving direction L of the movable member 3 is perpendicular. The neutral plane A that crosses the plane is arranged in an inclined state so as to have a mirror image positional relationship.

  A preferable range for the specific inclination angles of the vectors V1 and V2 is 45 ° ± 5 ° with respect to the drive surface 51. In order to increase the holding force of the movable member 3 by the driving device 6, the angle formed by the vectors V <b> 1 and V <b> 2 of the piezoelectric element 63 with respect to the driving piece 61 is narrowed (acute), and the moving amount of the movable member 3 is increased. To increase the angle of the vectors V1 and V2 of the piezoelectric element 63 with respect to the drive piece 61, such as widening (obtuse angle), the vector of the piezoelectric element 63 of the drive device 6 according to the specifications of the guide device 1. The angle formed by V1 and V2 is appropriately set.

  A pair of drive devices 6 are arranged in the opposite directions toward the drive surface 51. Specifically, in the first embodiment, the driving device 6 includes the movable member 61 in a state where the driving pieces 61 face each other so as to sandwich the movable member 3 from both sides along the moving direction L as shown in FIG. 3 are arranged on a straight line perpendicular to the moving direction L. Further, three sets of the drive devices 6 thus provided are arranged side by side along the moving direction L of the movable member 3.

  The operation of the guide device 1 configured as described above will be described with reference to FIGS. The guide device 1 applies a voltage change of a waveform having a phase difference and inverted in the time axis direction to each of the two piezoelectric elements 63 provided in one drive device 6. As a result, the drive piece 61 is caused to reciprocate in a plane that intersects the drive surface 51 along the movement direction L. While the contact portion 64 is in contact with the drive surface 51, the movable member 3 is held by the drive device 6 and is sent in one direction.

  And the phase of the return motion of the drive piece 61 is synchronized between the drive devices 6 provided in a pair with the movable member 3 interposed therebetween, and is in a different set directed toward the same drive surface 51 along the moving direction L of the movable member 3. Shift between the drive devices 6. Further, when the voltage change applied to the two piezoelectric elements 63 provided in one drive device 6 is reversed in the time axis direction, the revolving motion C of the drive piece 61 is reversed. That is, the moving direction L of the movable member 3 is reversed.

  In any case, the piezoelectric element 63 of each driving device 6 has a perpendicular line S in which the vectors V1 and V2 extending in the direction in which a voltage is applied pass through the contact portion 64 of the driving piece 61 with respect to the driving surface 51. Leaning from. When the driving device 6 moves the driving piece 61 in the moving direction of the movable member 3 while pressing the driving piece 61 against the driving surface 51, the voltage applied to one piezoelectric element 63 is gradually increased so that the piezoelectric element 63 is moved. At the same time, the piezoelectric element 63 is contracted by gradually decreasing the voltage applied to the other piezoelectric element 63. In this case, if the other piezoelectric element 63 contracts faster than one piezoelectric element 63 expands, the driving piece 61 cannot be pressed against the driving surface 51 with sufficient force.

  That is, the driving device 6 presses the driving piece 61 against the driving surface 51 and moves the movable member 3 by extending one piezoelectric element 63 before the other piezoelectric element 63 contracts. . As a result, compressive stress acts on each piezoelectric element 63 and tensile stress does not act on each piezoelectric element 63, so that the piezoelectric element 63 can be prevented from being damaged. Therefore, the reliability of the drive device 6 is improved, and further, the reliability of the guide device 1 including the drive device 6 is improved.

  In addition, the guide device 1 includes a pair of drive devices 6 that face the drive pieces 61 to each other, and synchronizes the return movements of the drive pieces 61, so that the movable member 3 receives the force received by the drive pieces 61. Components in the direction crossing the moving direction L cancel each other. Therefore, so-called yawing in which the movable member 3 is twisted from the direction along the moving direction L can be prevented.

  The state of the guide device 1 shown in FIG. 3 to FIG. 5 is a state in which the drive pieces 61 of the three sets of drive devices 6 are each reciprocating in one direction with a phase difference of 120 °. Is moving from right to left in the figure. The drive piece 61 of the drive device 6 moves while being pressed by the drive surface 51 provided on the friction member 5 of the movable member 3 from the feed start position to the feed end position in the orbital shape of the return motion. The drive piece 61 that has moved to the feed end position is separated from the drive surface 51 and returned to the feed start position. When the drive piece 61 reaches the feed start position, the drive piece 61 is pressed against the drive surface 51 again.

  In the state of FIG. 3, the leftmost drive piece 61 is the feed end position on the orbit of the return motion, the center drive piece 61 is the feed start position on the orbit of the return motion, and the right end drive piece 61 is the return position. Each is in the middle of return on the orbit of motion. In the state of FIG. 4, each drive piece 61 is in a state in which the phase has advanced by 120 ° from the state of FIG. 3, the leftmost drive piece 61 is in the middle of returning, the central drive piece 61 is the feed end position, and the right end The drive piece 61 is in the feed start position. In the state of FIG. 5, each drive piece 61 is in a state in which the phase is further advanced by 120 ° from the state of FIG. 4, the left end drive piece 61 is the feed start position, and the center drive piece 61 is in the middle of return, the right end The drive piece 61 is in the feed end position. Then, when the phase advances by 120 ° from the state of FIG. 5, the state of FIG. 3 is obtained again. In this way, the guide device 1 controls each driving device 6 and repeats from the state of FIG. 3 to the state of FIG. 5, thereby moving the movable member 3 from the right to the left in the drawing as shown in FIGS. 3 to 5. Move to.

  Further, the guide device 1 holds the movable member 3 by the drive piece 61 of any one of the drive devices 6 while the movable member 3 is moved. That is, the movable member 3 is supported by the drive pieces 61 of at least two drive devices 6. Therefore, the movable member 3 can be moved in a stable state relative to the base 2 and the amount of movement of the movable member 3 can be accurately grasped, so that the positioning accuracy of the movable member 3 with respect to the base 2 is good.

  Furthermore, by controlling the voltage change applied to the piezoelectric element 63 so that the drive piece 61 is in contact with the drive surface 51 continuously for 240 ° or more with respect to the phase of the return motion of the drive piece 61, the movable member 3 is Always supported at 4 or more locations. That is, when the movable member 3 is moved by providing an equal phase difference according to the number of the drive devices 6 arranged in the movement direction L, the drive pieces 61 of the two or more sets of the drive devices 6 are in contact with the drive surface 51. Each drive device 6 is controlled so as to be In other words, regarding the phase of the return motion of the drive piece 61, (the phase angle at which the drive piece 61 is in contact with the drive surface 51) ≧ [{360 ° / (the number of drive devices 6 arranged in the moving direction L of the movable member 3). )} × 2], the guide device 1 can hold the movable member 3 with four or more driving pieces 61.

  The guide device 1 can change the moving speed of the movable member 3 by changing the frequency of the periodic voltage change applied to each piezoelectric element 63. When the movable member 3 is moved slowly, the guide device 1 causes the drive pieces 61 to move along the moving direction L of the movable member 3 while bringing the drive pieces 61 into contact with the drive surface 51 with a substantially constant pressing force. Is applied to each piezoelectric element 63. Further, when the movable member 3 is moved quickly, the wavelength of the voltage change waveform may be shortened. In this case, when the wavelength is shortened, the characteristic waveform is rounded by the response speed of the voltage change of the piezoelectric element 63 and approximated to a sine wave shape. Therefore, the moving speed of the movable member 3 can be increased by applying a sinusoidal high frequency voltage having a phase difference to each piezoelectric element 63 of the driving device 6.

  Therefore, a band including the natural frequency of the piezoelectric element 63, the natural frequency of the piezoelectric element 63 with the driving piece 61 attached thereto, or the natural frequency in addition to the natural frequency of the elastic hinge 62b. If the frequency of the high frequency voltage is set to, the driving force for reciprocating the driving piece 61 is supplemented by resonance. Therefore, the drive device 6 and the guide device 1 including the same can move the movable member 3 efficiently, and can easily stabilize the moving speed and the moving amount of the movable member 3.

  When the movable member 3 is finely moved within the range of the contact portion 64 of the driving piece 61 with respect to the base 2, the balance of the voltages applied to the two piezoelectric elements 63 of each driving device 6 is adjusted. 7, the drive piece 61 is rotated so that the contact portion 64 of the drive piece 61 is in rolling contact with the drive surface 51. In this case, the drive piece 61 of each drive device 6 may synchronize each rotation angle, and may be in the state which has a phase difference as shown in FIGS.

  In the first embodiment, the guide device 1 has three pairs of driving devices 6 that are arranged on the driving surface 51 in the moving direction L of the movable member 3 so that the contact portions 64 are directed in opposite directions to each other. The device 6 has a configuration in which one drive piece 61 is attached to one frame. However, a plurality of frames 62 of the drive devices 6 arranged in the moving direction L of the movable member 3 are integrally provided, and a plurality of frames are provided in one frame. The drive piece 61 may be provided so as to be attached. In this case, each driving piece 61 is supported by at least two piezoelectric elements 63 with respect to the frame.

  A guide device 11 according to a second embodiment of the present invention will be described with reference to FIG. In addition, about the structure which has the same function as the guidance apparatus 1 in 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. In the guide device 11 shown in FIG. 8, a plurality of pairs of drive devices 6 arranged so as to sandwich the movable member 3 from both outer sides are arranged side by side in a direction crossing the moving direction L of the movable member 3. Specifically, in the present embodiment, the driving device 6 is arranged so as to overlap three sets.

  A pair of drive devices 6 facing the drive piece 61 synchronize the phase of the return movement of the drive piece 61, and the different sets of drive devices 6 arranged facing each other and facing the same drive surface 51 are overlapped. The phases of the return movements of the drive piece 61 are shifted from each other. In the state of FIG. 8, the drive piece 61 of the upper drive device 6 is in the middle of return on the orbit of the return motion, while the drive piece 61 of the intermediate drive device 6 is the feed end position on the return orbit of the return motion, the lower step. The driving piece 61 of the driving device 6 is located at the starting position of the circular orbit of the reciprocating motion.

  The guide device 11 configured as described above differs from the guide device 1 of the first embodiment only in the direction in which the drive device 6 is arranged, and the control of each drive device 6 is the same. It is. Therefore, the guide device 11 of the second embodiment can move the movable member 3 in the same manner as the guide device 1 of the first embodiment. Moreover, since the drive device 6 is arranged in a direction crossing the moving direction L of the movable member 3 as compared with the guide device 1 of the first embodiment, the mounting area of the drive device 6 can be reduced.

  In the guide device 1 of the first embodiment and the guide device 11 of the second embodiment, the pair of drive devices 6 are straight lines orthogonal to the moving direction L of the movable member 3 with the drive pieces 61 facing each other. Although arranged above, the drive pieces 61 may be arranged on a straight line orthogonal to the moving direction L of the movable member 3 with the drive pieces 61 facing away from each other. By disposing like the latter, the drive device 6 is hidden inside the width of the movable member 3 of the guide device 1 and the guide device 11, that is, hidden inside the movable member 3. 6 is protected and the appearance is improved. Further, not only the frames 62 of the drive devices 6 arranged in the moving direction L of the movable member 3 are integrated, but also the frames 62 of the drive devices 6 that synchronize the return movement of the drive pieces 61 are integrated. become able to.

  Further, the guide device 1 of the first embodiment arranges the driving device 6 in the moving direction L of the movable member 3, and the guiding device 11 of the second embodiment places the driving device 6 in the moving direction L of the movable member 3. However, if both of these forms are adopted and the drive devices 6 are arranged in multiple rows and multiple stages in the direction crossing the moving direction L of the movable member 3 and the moving direction L, the movable member 3 is more It can be moved with a large driving force.

  A rotating device 101 according to a third embodiment of the present invention will be described with reference to FIGS. 9 and 10. In addition, about the structure which has the same function as the guidance apparatus 1 in 1st Embodiment, and the guidance apparatus 11 in 2nd Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  In the rotating device 101 shown in FIG. 9, the movable member 103 is formed in a disk shape, and instead of the guiding mechanism 4 in the guiding device 1 of the first embodiment and the guiding device 11 of the second embodiment, it rolls. A bearing 104 is provided. As shown in FIG. 10, the rolling bearing 104 includes a first member 141, a second member 142, and a plurality of rolling elements 143 that are in rolling contact with each other. Thereby, the movable member 103 rotates with respect to the base 2. The first member 141 is fixed to the base 2, and the second member 142 is fixed inside the outer peripheral edge 131 of the movable member 103. The friction member 105 is provided concentrically along the rotation direction M on the outer side of the outer peripheral edge 131 of the movable member 103.

  The drive devices 106 are arranged concentrically and equally around the movable member 103, and the contact portion 64 of the drive piece 61 is directed to the drive surface 151 of the friction member 105. In the present embodiment, the six driving devices 106 are equally spaced by 60 ° with respect to the rotation center line T of the movable member 103 in a state where the contact portion 64 of the driving piece 61 faces the rotation center line T of the movable member 103. Is arranged.

  The driving piece 61 is attached to the frame 162 fixed to the base 2 by a piezoelectric element 63. The frame 162 is curved in a sector shape along the outer diameter of the movable member 103. The piezoelectric element 63 is attached in such a direction that vectors V1 and V2 extending in a direction in which a voltage is applied pass through the driving piece 61 and obliquely cross the driving surface 151. Specifically, the vectors V1 and V2 in the extending direction of the neutral plane A perpendicular to the drive surface 151 through the contact portion 64 of the drive piece 61, that is, the plane through which the rotation center line T of the movable member 103 passes. Are inclined in a mirror image positional relationship.

  The rotation device 101 makes a pair of drive devices 106 arranged at a symmetrical position with respect to the rotation center line T to synchronize the phase of the return motion of the drive piece 61, and the rotation position differs with respect to the rotation center line T. The phase of the return motion of the drive piece 61 is shifted between the sets of the drive devices 106. In the case of the rotation device 101 according to the third embodiment, since the six drive devices 106 are arranged at equal intervals, the two drive devices 106 arranged in the diametric direction are used as a pair, and the three sets of drive devices 106 are: The return motion of each drive piece 61 is controlled by shifting the phase by 120 °. The direction in which the drive pieces 61 of the pair of drive devices 106 reciprocate is rotationally symmetric with respect to the rotation center line T.

  The voltage applied to each piezoelectric element 63 of one drive device 106 is applied in the same manner as the drive device 6 of the first embodiment. In this case, in the third embodiment, since the driving surface 151 has a curvature corresponding to the diameter of the movable member 103, what is the waveform of the voltage change applied to each piezoelectric element 63 in the first embodiment? Although slightly different, the waveform of the voltage change applied between the piezoelectric elements 63 arranged in a mirror image positional relationship with respect to the neutral surface A perpendicular to the driving surface 151 through the driving piece 61 is the time axis direction. The waveforms are mirror images of each other. Then, by reversing the waveform of the voltage change applied to each piezoelectric element 63 in the time axis direction, the direction of the return motion of the drive piece 61 is reversed, and as a result, the rotation direction M of the movable member 103 is reversed.

  Further, the rotating device 101 of the third embodiment is the same as the guiding device 1 and the second device of the first embodiment, except that the directions in which the driving pieces 61 of the pair of driving devices 106 return are the same. Similar to the guide device 11 of the embodiment, the movable member 103 can be rotated at a stable speed by applying high-frequency voltages having different phases to the driving devices 106 of different sets.

  By controlling each drive device 106 in this manner, the movable member 103 is supported by the pair of drive devices 106 positioned in the diametrical direction, so that the force acting on the movable member 103 from the drive piece 61 of the pair of drive devices 106. Of these, the radial component is canceled out. Therefore, the movable member 103 can be prevented from being eccentric, and the positioning accuracy of the movable member 103 with respect to the rotation center line T is improved.

  In the rotation device 101 of the third embodiment, the drive device 106 that synchronizes the phase of the return motion of the drive piece 61 is arranged at the rotation center line T in addition to being arranged at a symmetric position with respect to the rotation center line T. On the other hand, the drive devices 106 having different rotational positions by 120 ° may be set as one set to synchronize the phase of the return motion of the drive piece 61. By doing in this way, since the movable member 103 comes to be supported equally from 3 directions, the positioning accuracy with respect to eccentricity improves rather than supporting in the diameter direction.

  Further, in the rotation device 101 of the third embodiment, the driving device 106 is arranged in a concentric manner on the concentric circle with respect to the rotation center line T of the movable member 103. If at least two sets of drive devices 106 arranged in a pair opposite to each other are provided on the same line perpendicularly across the drive surface 151 of the friction member 105 arranged concentrically, The movable member 103 can be held while the movable member 103 is rotated by the driving device 106, and the positioning accuracy and rotational speed of the movable member 103 can be stabilized.

  Therefore, the friction member 105 is formed in a disk shape extending radially from the outer peripheral edge 131 of the movable member 103, and the friction member 105 faces the drive pieces 61 in the direction along the rotation center line T of the movable member. That is, the driving device 106 may be arranged in a state where the friction member 105 provided in a disk shape is sandwiched between the driving pieces 61 in the plate thickness direction. Alternatively, the friction member 105 is provided along the inner periphery of the movable member 103, and the driving device 106 disposed on the same diameter with the driving piece 61 facing the driving surface 151 formed on the inner peripheral surface of the friction member 105. As a pair, at least two sets of driving devices 106 may be arranged on different diameters.

  In the drawings of the first to third embodiments, the length of the piezoelectric element 63 that expands and contracts when a voltage is applied and the position of the drive piece 61 that makes a reciprocating motion are exaggerated for easy understanding. I'm drawing.

  A drive device 206 according to a fourth embodiment of the present invention will be described with reference to FIG. In addition, about the structure which has the same function as the drive devices 6 and 106 demonstrated in the 1st-3rd embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  In the drive device 206 shown in FIG. 11, four piezoelectric elements 63 are attached between the drive piece 61 and the frame 262. The piezoelectric element 63 is arranged in a direction in which vectors V1 and V2 extending in a direction in which a voltage is applied pass obliquely across the drive surface 51 through the drive piece 61. Two of the four piezoelectric elements 63 are paired in parallel, and the pair of piezoelectric elements 63 passes through the contact portion 64 of the drive piece 61 so that the main movement direction L1 of the movable member is perpendicular. They are arranged in a mirror image positional relationship with respect to the neutral plane A that crosses. The contact portion 64 of the drive piece 61 is formed in a curved surface having a curvature in each of the main movement direction L1 of the movable member and the sub movement direction L2 crossing the main movement direction L1. In the frame 262, a recess 62a for attaching the drive piece 61 is formed toward the drive surface 51, and a slit-like elastic hinge 62b is formed at a position on an extension line in the direction in which the piezoelectric element 63 extends. In the fourth embodiment, the elastic hinge 62b adjusts the pressing force (preload) against the drive surface 51 of the drive piece 61, and moves the movable member along the main movement direction L1 to the attachment portion of the piezoelectric element 63. In addition to the strain that occurs, it also acts to alleviate strain that occurs in the mounting portion of the piezoelectric element 63 when moving along the sub-movement direction L2.

  The drive device 206 configured as described above synchronizes the phase of the voltage change applied to the paired piezoelectric elements 63 and shifts the phase of the voltage change applied to the different pairs of piezoelectric elements 63. Similarly to the drive device 6 of the first and second embodiments, the movable member is moved in the main movement direction L1. Further, the phase of the voltage change applied to the pair of piezoelectric elements 63 is shifted, and the phase of the voltage change applied to the pair of piezoelectric elements 63 having a different mirror image positional relationship with respect to the neutral plane A is synchronized. Then, the movable member is moved in the sub moving direction L2.

  Thus, the drive device 206 of the fourth embodiment not only has the same function as the drive device 6 of the first and second embodiments, but also appropriately changes the phase of the voltage change applied to the four piezoelectric elements 63. By controlling, the movable member can also be moved in an oblique direction in which the main movement direction L1 and the sub movement direction L2 are combined.

  A drive device according to a fifth embodiment of the present invention will be described with reference to FIG. In addition, about the structure which has the same function as the drive device 6,106,206 in 1st-4th embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  In the driving device 306 shown in FIG. 12, three piezoelectric elements 63 are attached between the driving piece 61 and the frame 362. Each piezoelectric element 63 is arranged in a direction in which vectors V1, V2, and V3 extending in a direction in which a voltage is applied pass through the driving piece 61 and obliquely cross the driving surface 51. More specifically, the extension vectors V1, V2, and V3 of the piezoelectric elements 63 are provided in a state of being inclined in a rotationally symmetric positional relationship with respect to the normal S passing through the contact portion 64 of the drive piece 61 from the drive surface 51. And arranged equidistantly with respect to the perpendicular S.

  In this case, it is preferable that the angle formed by the vectors V1, V2, V3 and the perpendicular line S is in a range of 45 ° ± 5 °. However, when it is desired to increase the holding force of the movable member by the driving device 306, the angle formed by the vectors V1, V2, and V3 and the perpendicular S is narrowed (acute), and the amount of movement of the movable member is increased. The vector V1 depends on the specifications of the XY table or the like that moves the movable member in two axes, such as widening (obtuse) the angle formed by V1, V2, V3 and the perpendicular S. , V2, V3 and the perpendicular line S are appropriately set.

  The contact portion 64 of the drive piece 61 is formed in a spherical shape. In the frame 362, a recess 62a to which the drive piece 61 is attached is formed toward the drive surface 51, and a slit-like elastic hinge 62b is provided at a portion on which each piezoelectric element 63 is attached and extends in the extension direction of the piezoelectric element 63. Is formed. The frame 362 is formed in a hexagonal shape in the fifth embodiment in consideration of the number of piezoelectric elements 63 and considering that a plurality of drive devices 306 are arranged side by side. Since there are three piezoelectric elements 63, the outer shape of the frame 362 may be a triangle. Further, a quadrangular shape may be used so that a plurality of the piezoelectric elements 63 can be easily arranged side by side.

  The drive device 306 configured as described above further includes a control unit 307, and a voltage change in which the phase, amplitude, and waveform are individually set is applied to each piezoelectric element 63. Accordingly, the drive piece 61 can move the movable member along the drive surface 51 in two directions intersecting each other. Therefore, a large number of drive devices 306 are arranged along the flat drive surface 51 and are positioned and controlled by an orthogonal biaxial coordinate system, a so-called XY table, or a large number of drive devices 306 are arranged along a cylindrical drive surface. It can be used as a drive source for a device that performs positioning control in a coordinate system or a device that performs positioning control in a polar coordinate system by arranging a plurality of devices along a spherical drive surface. In addition, when a large number of drive devices 306 are arranged along the flat drive surface 51, in addition to the control along the orthogonal biaxial coordinate system, an arbitrary position of the drive surface 51 is perpendicular to the drive surface 51. The movable member can also be turned around a set axis.

The perspective view which shows the guide apparatus of 1st Embodiment which concerns on this invention. The top view which expands and shows the drive device of FIG. The top view which shows the drive state of the guide apparatus of FIG. The top view which shows the drive state of the guide apparatus of FIG. The top view which shows the drive state of the guide apparatus of FIG. The top view which shows the state which finely adjusts the position of a movable member with the drive device of FIG. The top view which shows the state which finely adjusts the position of a movable member with the drive device of FIG. The disassembled perspective view which shows the guide apparatus of 2nd Embodiment which concerns on this invention. The top view which shows the rotating apparatus of 3rd Embodiment which concerns on this invention. Sectional drawing which shows a rotation apparatus along F10-F10 in FIG. The perspective view which shows the drive device of 4th Embodiment which concerns on this invention. The perspective view which shows the drive device of 5th Embodiment which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Guide apparatus, 2 ... Base, 3 ... Movable member, 31 ... Side part, 4 ... Guide mechanism, 41 ... 1st member, 42 ... 2nd member, 43 ... Rolling element, 5 ... Friction member, 51 ... Drive 6, driving device, 61, driving piece, 62, frame, 63, piezoelectric element, 64, contact portion, 11, guiding device, 101, rotating device, 103, movable member, 131, outer peripheral edge, 104, bearing, 141 ... first member, 142 ... second member, 143 ... rolling element, 105 ... friction member, 151 ... drive surface, 106 ... drive device, 162 ... frame, 206 ... drive device, 262 ... frame, 306 ... drive device, 362: Frame, 307: Control unit, L: Movement direction, V1, V2, V3 ... Vector, S ... Vertical, A ... Neutral plane, C ... Circumference direction, M ... Rotation direction, T ... Rotation center line.

Claims (21)

A drive piece in which a contact portion is provided toward a drive surface provided in the movable member along a moving direction of the movable member that moves relative to the base;
A frame fixed to the base,
A vector extending in a direction to which a voltage is applied includes at least two piezoelectric elements attached between the driving piece and the frame in a direction passing through the driving piece and obliquely crossing the driving surface. To drive. At least one pair of driving pieces arranged in a pair with the contact portions facing in opposite directions to a pair of driving surfaces provided in parallel to the movable member along the moving direction of the movable member moving relative to the base;
At least one pair of frames fixed to the base and arranged in pairs facing each of the drive surfaces;
At least two vectors for each drive piece are attached between the drive piece and the frame in a direction that obliquely crosses the drive surface through the drive piece and is extended by applying a voltage. A drive device comprising: a piezoelectric element.   A pair of the drive pieces are arranged side by side in the moving direction of the movable member, and the pair of drive pieces operate in a mirror image positional relationship with respect to the drive surface and are arranged in the moving direction. The drive device according to claim 2, wherein the pieces operate in a positional relationship with a phase shift from each other.   The vector is provided in a state in which the piezoelectric element is inclined in a rotationally symmetric positional relationship with respect to a normal passing through the contact portion of the driving piece from the driving surface. The driving device according to any one of the above.   2. The vector according to claim 1, wherein the piezoelectric element is arranged such that the vector is inclined in a positional relationship of a mirror image with respect to a neutral plane passing through the driving piece and perpendicularly crossing the moving direction. Item 4. The driving device according to Item 3.   6. The driving device according to claim 1, wherein the piezoelectric element has the vector provided in an angle range of 45 ° ± 5 ° with respect to the driving surface. 7.   The drive device according to any one of claims 1 to 6, wherein the drive piece is caused to reciprocate by applying different voltage changes to each of the at least two piezoelectric elements.   The drive piece is periodically reciprocated by applying a high-frequency voltage having a phase difference to each of at least two of the piezoelectric elements. Drive device.   The driving device according to claim 8, wherein the frequency of the high-frequency voltage is set in a band including a natural frequency of the piezoelectric element.   Applying voltage changes in which phase, amplitude, and waveform are individually set to at least three of the piezoelectric elements to displace the driving piece, and moving the movable member in at least two directions intersecting each other along the driving surface The drive device according to any one of claims 1 to 8, further comprising a control unit to be moved. The base,
A movable member that moves relative to the base;
The first member and the second member that move relative to each other and a plurality of rolling elements that are in rolling contact with each other, and one of the first member and the second member is fixed to the base A guide mechanism with the other attached to the movable member;
At least two friction members provided in parallel along the moving direction of the movable member;
And at least two sets of driving devices arranged in a pair opposite to each other toward the driving surface of the friction member along the moving direction,
Each said driving device is
A direction in which a driving piece provided with a contact portion toward the driving surface, a frame fixed to the base, and a vector extending in a direction in which a voltage is applied crosses the driving surface diagonally through the driving piece. And at least two piezoelectric elements attached between the drive piece and the frame,
By applying a high frequency voltage having a phase difference to at least two of the piezoelectric elements, the drive piece is periodically regressed, and the phases of the return movements of the drive pieces provided in the pair of drive devices are synchronized. And moving the movable member in one direction along the moving direction by controlling to shift the phase of the return movement of the drive pieces provided in the drive devices of different sets directed to the same drive surface, and the return movement The guide device is characterized in that the movable member is moved to the other side in the moving direction by performing the control by reversing the direction of rotation.   The driving surface is provided in parallel along the moving direction of the movable member, and the pair of driving devices are arranged on a straight line orthogonal to the moving direction with the driving pieces facing each other. The guide device according to claim 11.   The driving surface is provided in parallel along the moving direction of the movable member, and the pair of driving devices are arranged on a straight line perpendicular to the moving direction with the driving pieces facing away from each other. The guide device according to claim 11 or 12.   The guide device according to any one of claims 11 to 13, wherein a plurality of sets of the drive devices are arranged in the moving direction.   The guide device according to any one of claims 11 to 14, wherein a plurality of sets of the drive devices are arranged in a direction crossing the moving direction. The base,
A movable member that rotates relative to the base;
The first member and the second member that rotate relative to each other and a plurality of rolling elements that are in rolling contact with each other, and one of the first member and the second member is fixed to the base A rolling bearing with the other attached to the movable member;
A friction member provided concentrically with respect to the rotation center line of the movable member;
And at least two sets of driving devices arranged in a pair opposite to each other on the same line perpendicularly crossing a driving surface formed along the rotation direction of the friction member,
Each said driving device is
A direction in which a driving piece provided with a contact portion toward the driving surface, a frame fixed to the base, and a vector extending in a direction in which a voltage is applied crosses the driving surface diagonally through the driving piece. And at least two piezoelectric elements attached between the drive piece and the frame,
By applying a high frequency voltage having a phase difference to at least two of the piezoelectric elements, the drive piece is periodically regressed, and the phases of the return movements of the drive pieces provided in the pair of drive devices are synchronized. And moving the movable member in one direction along the rotational direction by controlling to shift the phase of the return motion of the drive pieces provided in the drive devices of different sets directed to the same drive surface, and the return motion The rotating device is characterized in that the movable member is moved to the other along the rotation direction by performing the control by reversing the rotation direction.   The drive surface is provided perpendicular to the rotation center line of the movable member, and the pair of drive devices follow the rotation center line in a state where the drive pieces face each other in a direction along the rotation center line. The rotating device according to claim 16, wherein the rotating device is arranged in a direction.   The drive surface is provided along the outer periphery of the movable member, and the pair of drive devices are arranged on a straight line orthogonal to the rotation center line in a state where the drive piece faces the rotation center line of the movable member. The rotating device according to claim 16 or 17, characterized in that:   The drive surface is provided along the inner periphery of the movable member, and the pair of drive devices are orthogonal to the rotation center line in a state in which the drive piece is directed away from the rotation center line of the movable member. The rotating device according to any one of claims 16 to 18, wherein the rotating device is arranged on a straight line.   The rotating device according to any one of claims 16 to 19, wherein the driving devices are arranged in a plurality of equal intervals in the rotating direction.   The rotating device according to any one of claims 16 to 20, wherein a plurality of sets of the driving devices are arranged in a direction along a rotation center line of the movable member.

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