JP2011244598A - Ultrasonic motor and driving device provided with ultrasonic motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic motor which can totally remove a wear powder deposited on a slide member, prevents the deterioration of driving efficiency and driving performance, and prevents the shortening of a life.SOLUTION: The ultrasonic motor comprises: an oscillator 11 which excites vibration; drive elements 12a and 12b provided on the oscillator 11; a holder 13 which holds the oscillator 11; and a grind stone 14 for grinding provided in the holder 13. The grind stone 14 for grinding is constituted so as to be capable of adjusting a position.

Description

  The present invention relates to an ultrasonic motor and a driving device including the ultrasonic motor, and more particularly to an ultrasonic motor and a driving device including the ultrasonic motor that are used in precision processing apparatuses, semiconductor manufacturing apparatuses, microscope stages, and the like.

  When observing a fine structure using a microscope, an XY stage is used to position an arbitrary position of an observation target under the microscope observation. At this time, the XY stage is required to have a feed resolution equivalent to the microstructure to be observed and stability at rest.

  Ultrasonic motors are attracting attention as one of actuators that meet such needs. Ultrasonic motors are characterized in that they can be positioned with higher accuracy than conventional motors that use Lorentz force, and have a large holding force without being energized when stationary.

  The ultrasonic motor includes a piezoelectric element that generates vibration in the ultrasonic region and a driver that vibrates with the vibration of the piezoelectric element, and presses the driver against a sliding member provided on the driven body. Generate driving force. However, since the driving force is obtained by the friction between the driving element and the sliding member, the driving element and the sliding member gradually wear. If the wear powder generated by the wear adheres to the sliding member, it may cause a malfunction, and further promote the wear of the driver and the sliding member to shorten the life of the ultrasonic motor. There was a problem. Therefore, it has been necessary to replace the driver and the sliding member or the ultrasonic motor itself at regular intervals.

  In order to solve such a problem, for example, in Patent Document 1, a brush is charged with a polarity different from that of wear powder generated by sliding between a friction member and a driving force transmission member, and mechanical scratching is performed. There has been proposed an ultrasonic motor driving apparatus that can adsorb wear powder to a brush by electrostatic force.

JP 2004-236389 A

  However, when the driver element is formed of a material having a resin as a base material, the abrasion powder is applied to the sliding member by sliding the driver element with the abrasion powder adhering to the sliding member. May end up. In such a case, the wear powder applied to the sliding member has a strong adhesive force and cannot be removed simply by scraping. For this reason, the method using the brush as proposed in Patent Document 1 cannot completely remove the wear powder, and the brush presses the wear powder against the sliding member, so that the wear powder is applied to the sliding member. There is also a risk of smearing. Therefore, a method of removing the abrasion powder using a harder material brush is also conceivable. However, in this method, the sliding surface of the sliding member may be damaged, and the operation efficiency may be reduced. There is a similar concern when a roller or felt is used as a means for removing abrasion powder instead of the brush. Alternatively, a method of scraping off the wear powder together with the sliding member using a scraper, a peeling claw, or the like as the wear powder removing means may be considered. However, in this method, it is difficult to maintain the surface accuracy of the sliding member, and there is a possibility that the driving efficiency and driving performance may be lowered or the driving operation may not be performed.

  In view of the above circumstances, the present invention can completely remove the wear powder adhering to the sliding member, and can prevent a reduction in driving efficiency and driving performance and a reduction in life, and an ultrasonic motor and an ultrasonic wave. An object of the present invention is to provide a driving device including a motor.

  An ultrasonic motor according to a first aspect of the present invention is provided with a vibrator for exciting vibration, a driver provided in the vibrator, a holding means for holding the vibrator, and a holding means. A grinding wheel, and the grinding wheel is configured to be arranged and adjustable.

  The ultrasonic motor according to a second aspect of the present invention is the ultrasonic motor according to the first aspect, wherein the driving element abuts on a sliding member provided on a driven body that is movably supported with respect to the fixed portion. When the holding means is fixed to the fixed portion so as to be pressed, the grinding wheel is configured to be adjustable in a direction perpendicular to the sliding surface of the sliding member. To do.

  An ultrasonic motor according to a third aspect of the present invention is the ultrasonic motor according to the second aspect, wherein the grinding wheel is disposed so as to be in contact with or pressed against the sliding member. In addition, the grinding wheel is in contact with the sliding member on a surface.

The ultrasonic motor according to a fourth aspect of the present invention is characterized in that, in any one of the first to third aspects, the grinding wheel is provided on both sides of the vibrator.
In the ultrasonic motor according to the fifth aspect of the present invention, in the fourth aspect, in the grinding wheel provided on both sides of the vibrator, the grinding wheel provided on one side has coarse particles, The grinding wheel provided on the other side is characterized by fine particles.

  An ultrasonic motor according to a sixth aspect of the present invention is the ultrasonic motor according to the fifth aspect, wherein the grinding wheel with coarse particles is arranged so as to be in contact with and pressed against the sliding member. When the driving body is driven, the grinding wheel with fine particles is arranged so as not to contact the sliding member, and the grinding wheel with fine particles contacts and is pressed against the sliding member. When the driven body is driven in such a state, the grinding wheel with coarse particles is arranged so as not to contact the sliding member.

  The ultrasonic motor according to a seventh aspect of the present invention is the ultrasonic motor according to the sixth aspect, wherein the grinding wheel with coarse particles is pressed against the sliding member and pressed, and the fine particles are The pressing force when the grinding wheel comes into contact with and is pressed against the sliding member is different.

  The ultrasonic motor according to an eighth aspect of the present invention is the ultrasonic motor according to any one of the first to seventh aspects, wherein the grinding wheel is configured to be arranged and adjustable by the action of a screw. .

  An ultrasonic motor according to a ninth aspect of the present invention is the ultrasonic motor according to any one of the first to seventh aspects, wherein the grinding wheel is configured to be adjustable by an action of a single-axis piezo element. Features.

  A driving apparatus according to a tenth aspect of the present invention is provided with a base portion, a table supported to be movable with respect to the base portion, a sliding member provided on the table, and the base portion. The ultrasonic motor according to any one of the first to ninth aspects, wherein the ultrasonic motor holding means is configured such that the ultrasonic motor driver contacts a sliding member provided on the table. The grinding wheel is fixed to the base portion so as to be pressed, and the grinding wheel is configured to be arranged and adjusted in a direction perpendicular to the sliding surface of the sliding member.

  According to the present invention, it is possible to completely remove the wear powder adhering to the sliding member in the ultrasonic motor and the driving device including the ultrasonic motor, thereby preventing the driving efficiency and the driving performance from being lowered and the life from being shortened. can do.

1 is a diagram schematically illustrating a configuration example of an ultrasonic motor according to Embodiment 1. FIG. It is a figure which shows typically the structural example at the time of providing a hole and the screw comprised integrally with the grindstone for grinding via a grindstone seat on both sides of a vibrator. 6 is a diagram schematically illustrating a configuration example of an ultrasonic motor according to Embodiment 2. FIG. FIG. 6 is a diagram schematically illustrating an upper surface of a drive device according to a third embodiment. It is a figure which shows typically the AA 'cross section (refer FIG. 4) of the drive device which concerns on Example 3. FIG. It is a figure which shows typically the side surface of the drive device which concerns on Example 3 seen from the ultrasonic motor side.

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

  The ultrasonic motor according to the first embodiment of the present invention is an ultrasonic motor that drives a driven body that is movably supported with respect to a fixed portion. For example, the ultrasonic motor may be a microscope stage, a precision processing apparatus, a semiconductor manufacturing apparatus, Applicable as an actuator to be used.

FIG. 1 is a diagram schematically illustrating a configuration example of an ultrasonic motor according to the present embodiment.
In addition, although the figure shows typically the upper surface of the ultrasonic motor which concerns on a present Example, the one part is shown as a cross section for convenience of explanation.

  As shown in the figure, the ultrasonic motor according to the present embodiment is a vibrator 11 that excites vibration, driver elements 12 a and 12 b provided on the vibrator 11, and a holding unit that holds the vibrator 11. The holder 13 and the grinding wheel 14 provided on the holder 13 are provided. As will be described in detail later, the grinding wheel 14 can be arranged and adjusted.

  The driver elements 12a and 12b are fixed to the side surface of the vibrator 11 on the side of the driven body (not shown). Is formed.

  The vibrator 11 is composed of a laminated piezoelectric material (piezo element) having a bending vibration electrode and a longitudinal vibration electrode (not shown). When a predetermined drive signal is given from a control device (not shown), the vibrator 11 performs bending vibration and longitudinal vibration. Exciting and utilizing these vibrations causes the drivers 12a and 12b to generate elliptical motion. Accordingly, when the holder 13 is fixed to the fixed portion so that the driver elements 12a and 12b are brought into contact with and pressed against the sliding member provided on the driven body, the driver elements 12a and 12b that perform the elliptical motion The driven body can be driven by friction with the sliding member.

  The holder 13 has a leaf spring portion 13b formed by a notch hole 13a provided in a part thereof. The leaf spring portion 13b includes a thick portion that does not act as a spring in part, and the vibrator 11 is fixed to the thick portion. The holder 13 is formed with a hole 13c including a female screw. A screw 16 integrally formed with the grinding wheel 14 is inserted into the hole 13c via the grinding wheel seat 15, and the grinding wheel 14 is arranged by adjusting the screwing amount of the screw 16. It is configured to be adjustable. Further, when the holder 13 is fixed to the fixed portion so that the driver elements 12a and 12b are brought into contact with and pressed against the sliding member provided in the driven body, by adjusting the screwing amount of the screw 16, The grinding wheel 14 is configured to be adjustable in the direction perpendicular to the sliding surface of the sliding member. Furthermore, when the grinding wheel 14 is arranged to come into contact with the sliding member or to be pressed against the sliding member, the grinding wheel 14 is configured to come into contact with the sliding member on the surface. . At this time, the size of the surface is within a range including a range in which the driver elements 12a and 12b slide on the sliding member during normal driving described later, and the grinding wheel 14 slides (grinds) during cleaning driving described later. It is configured to be as large as possible. With such a configuration, the grinding wheel 14 is brought into contact with and pressed against the sliding member and is separated from the sliding member, as well as the pressing force when the grinding wheel 14 is pressed against the sliding member. It can also be adjusted.

  In the ultrasonic motor according to this embodiment having such a configuration, the holder 13 is fixed to the fixing portion so that the driving elements 12a and 12b are brought into contact with and pressed against the sliding member provided on the driven body. Sometimes, a normal drive for driving the driven body to a desired position and a cleaning drive for driving the driven body to remove the abrasion powder adhering to the sliding member can be performed.

  In the normal driving, the driven body is driven in a state where the screwing amount of the screw 16 is adjusted so that the grinding wheel 14 does not contact the sliding member. On the other hand, in the cleaning driving, the driven body is reciprocated in a state where the screwing amount of the screw 16 is adjusted so that the grinding wheel 14 is brought into contact with and pressed against the sliding member.

  In the ultrasonic motor according to this embodiment, when normal driving is repeatedly performed, the sliding member and the driver elements 12a and 12b gradually wear, and wear powder generated by the wear gradually adheres to the sliding member. However, the abrasion powder adhering to the sliding member can be removed by performing a cleaning drive.

  When cleaning driving is performed, the grinding wheel 14 finely grinds the sliding member provided on the driven body, and therefore wear powder adhering to the sliding member (such as wear powder applied to the sliding member is also present). Can be completely removed. Further, since the grinding wheel 14 is in contact with the sliding member on the surface, there is no possibility of causing local scratches on the sliding member, such as when a hard brush is used, and the driving characteristics of the ultrasonic motor are good. Can be maintained.

  Such cleaning drive is performed periodically or when necessary, such as according to the driving distance and driving time of the driven body, or when it is confirmed that the abrasion powder is attached to the sliding member visually. It is desirable to do. Further, it is desirable that the number of times the driven body is reciprocated during the cleaning drive is such that the abrasion powder adhering to the sliding member can be removed. Further, the range in which the driven body is driven to reciprocate during cleaning driving includes the range in which the grinding wheel 14 grinds the sliding member, and includes at least the range in which the driver elements 12a and 12b slide on the sliding member during normal driving. Such a range is desirable. For example, the range in which the driven body is driven to reciprocate during the cleaning drive can be set to be slightly wider than the entire range of the sliding member or the range in which the driver elements 12a and 12b slide on the sliding member during normal driving. . Further, for example, as the cleaning drive, the driven body can be driven so that the entire range of the sliding member is reciprocated 20 times for every 1 km of the driven body driving distance during normal driving.

  As described above, according to the ultrasonic motor according to the present embodiment, the wear powder adhered to the slide member by grinding the slide member itself with the grinding wheel 14 (the wear powder applied to the slide member is also included). Can be completely removed. Further, it is possible to prevent the drive efficiency and drive performance from being reduced and the life of the ultrasonic motor from being shortened due to the driver elements 12a and 12b biting the wear powder.

The ultrasonic motor according to the present embodiment can be modified as follows.
For example, in the ultrasonic motor according to the present embodiment, the hole 13c, the grinding wheel so that a suitable pressing force to the sliding member by the grinding wheel 14 can be obtained when the screw 16 is screwed in until the screw 16 comes into contact. 14, the grindstone 15 and the screw 16 may be designed in advance.

  Further, for example, in the ultrasonic motor according to the present embodiment, the hole 13c and the screw 16 integrally formed with the grinding wheel 14 via the grinding wheel seat 15 are provided on the right side portion of the holder 13 shown in FIG. However, the position of the holder 13 is not limited to the position shown in FIG. 1.

  Further, for example, the ultrasonic motor according to the present embodiment is configured such that the hole 13 c and the screw 16 integrally formed with the grinding wheel 14 via the grinding wheel seat 15 are provided on one side of the vibrator 11. However, it may be configured to be provided on both sides of the vibrator 11.

  FIG. 2 is a diagram schematically showing a configuration example in which the holes 13c and the screws 16 integrally formed with the grinding wheel 14 via the grinding wheel seat 15 are provided on both sides of the vibrator 11. It is. This figure also schematically shows the upper surface of the ultrasonic motor according to this configuration example, but a part thereof is shown as a cross-section for convenience of explanation.

  In this configuration example, similarly to the right side portion of the holder 13 shown in the figure, a hole 13c including a female screw is formed in the left side portion, and a grinding wheel 14 for grinding is provided in the hole 13c via a grinding wheel seat 15. And a screw 16 which is configured integrally with is inserted.

  As in the first embodiment, in normal driving, the screwing amounts of the two left and right screws 16 are adjusted so that the two grinding wheels 14 for left and right do not contact a sliding member provided on a driven body (not shown). The driven body is driven in the state, and in the cleaning drive, the screwing amounts of the two left and right screws 16 are adjusted so that the two grinding wheels 14 on the left and right are brought into contact with and pressed against the sliding member symmetrically. In this state, the driven body is reciprocated.

  In this configuration example, since the number of grinding wheels for grinding the sliding member increases, even if the number of reciprocating drives of the driven body during the cleaning driving is reduced, the wear powder (sliding on the sliding member) (Including wear powders applied to the member) can be completely removed.

  As described above, according to this configuration example, the abrasion powder (including the abrasion powder applied to the sliding member) completely removed by the cleaning driving by the reciprocating driving less times is completely removed. can do. Further, by adjusting the screwing amounts of the two left and right screws 16 so that the pressing force to the sliding member by the grinding wheel 14 is bilaterally symmetrical, the surfaces of the two left and right grinding wheels 14 that are in contact with the sliding member Accuracy can be ensured. Further, it is possible to prevent the drive efficiency and drive performance from being reduced and the life of the ultrasonic motor from being shortened due to the driver elements 12a and 12b biting the wear powder.

Note that the configuration example shown in FIG. 2 can be further modified as follows.
For example, each of the left and right holes 13c is ground so that a suitable pressing force to the sliding member by the left and right grinding wheels 14 can be obtained symmetrically when the two right and left screws 16 are screwed into contact. It is also possible to configure so that the grinding wheel 14, the grinding wheel seat 15, and the screw 16 are designed in advance.

  Further, for example, it is also possible to configure one grinding wheel 14 as a coarse grindstone and the other grinding wheel 14 as a fine grindstone. In the case of such a configuration, the cleaning drive can be performed as follows, for example. First, the screwing amount of the screw 16 is adjusted so that the coarser grinding wheel 14 is pressed against the sliding member, and the finer grinding wheel 14 is moved to the sliding member. The driven body is reciprocated in a state where the screwing amount of the screw 16 is adjusted so that the screw 16 is not in contact with the driven member. Next, the screwing amount of the screw 16 is adjusted so that the grinding wheel 14 with finer particles contacts and is pressed against the sliding member, and the grinding wheel 14 with coarser particles becomes the sliding member. The driven body is reciprocated in a state where the screwing amount of the screw 16 is adjusted so as not to be in contact. By performing such cleaning driving, rough grinding is first performed on the sliding member to which the wear powder has adhered, and then fine grinding is performed. Further, when such a cleaning drive is performed, the grinding wheel 14 with a finer particle is slid when the grinding wheel 14 with a coarser particle abuts against the sliding member and is pressed. It is also possible to adjust the screw 16 so as to be smaller than the pressing force when it is brought into contact with and pressed against the member. Alternatively, each of the left and right holes 13c, the grinding wheel 14, the grinding wheel seat 15, and the screw 16 so that the pressing force by the left and right grinding wheels 14 is different when the screw 16 is screwed in until it comes into contact. It is also possible to design in advance.

  The ultrasonic motor according to the second embodiment of the present invention is an ultrasonic motor that drives a driven body that is supported so as to be movable with respect to the fixed portion, similarly to the ultrasonic motor according to the first embodiment. The ultrasonic motor according to the first embodiment has a configuration in which the grinding wheel can be adjusted by the action of a screw, whereas the grinding wheel can be adjusted by the action of a single-axis piezo element instead of the screw. It is composed. The ultrasonic motor according to the present embodiment can also be applied as an actuator used in, for example, a microscope stage, a precision processing apparatus, a semiconductor manufacturing apparatus, and the like.

FIG. 3 is a diagram schematically illustrating a configuration example of the ultrasonic motor according to the present embodiment.
As shown in the figure, in the ultrasonic motor according to the present embodiment, a grindstone seat 21 is fixed to a side surface of the holder 13 on the side of the driven body (not shown), and a grinding wheel is ground on the side surface of the grindstone seat 21 on the side of the driven body. 14 is fixed.

  The grindstone 21 is composed of a uniaxial piezo element having an electrode (not shown), and in an uniaxial direction (vertical direction in the figure) with an extension amount corresponding to the electric signal according to an electric signal given from a control device (not shown). Elongate. Therefore, by adjusting the electric signal applied to the grindstone 21, the grinding wheel 14 can be arranged and adjusted via the grindstone 21 that is stretched in the uniaxial direction by the amount of elongation corresponding to the electric signal. Further, when the holder 13 is fixed to a fixing portion (not shown) so that the driving elements 12a and 12b are brought into contact with and pressed by a sliding member provided on the driven body, an electric signal to be given to the grindstone seat 21 is adjusted. Thus, the grinding wheel 14 is configured to be adjustable in the vertical direction with respect to the sliding surface of the sliding member. Furthermore, when the grinding wheel 14 is arranged to come into contact with the sliding member or to be pressed against the sliding member, the grinding wheel 14 is configured to come into contact with the sliding member on the surface. . At this time, the size of the surface is within a range including a range in which the driver elements 12a and 12b slide on the sliding member during normal driving described later, and the grinding wheel 14 slides (grinds) during cleaning driving described later. It is configured to be as large as possible. With such a configuration, the grinding wheel 14 is brought into contact with and pressed against the sliding member and is separated from the sliding member, as well as the pressing force when the grinding wheel 14 is pressed against the sliding member. It can also be adjusted.

Other configurations are the same as those of the ultrasonic motor according to the first embodiment.
Also in the ultrasonic motor according to the present embodiment, the normal drive and the cleaning drive can be performed in the same manner as the ultrasonic motor according to the first embodiment. However, in the normal drive of the ultrasonic motor according to the present embodiment, the electrical signal applied to the grinding wheel seat 21 is adjusted so that the grinding wheel 14 does not contact the sliding member (or the electrical signal is applied to the grinding wheel seat 21). The driven body is driven in a state in which it is not applied). Further, in the cleaning drive, the driven body is reciprocated in a state in which an electric signal applied to the grindstone seat 21 is adjusted so that the grinding wheel 14 contacts and is pressed against the sliding member. The timing for performing the cleaning drive, the number of times the driven body is driven to reciprocate during the cleaning drive, and the range in which the driven body is driven to reciprocate during the cleaning drive are the same as the timing, frequency, and range described in the first embodiment. Can be done.

  As described above, according to the ultrasonic motor according to the present embodiment, the same effects as those of the ultrasonic motor according to the first embodiment can be obtained, and further, the grinding wheel 14 can be adjusted by adjusting the electric signal applied to the grindstone seat 21. Since the arrangement can be adjusted, it is not necessary to make fine adjustments based on the power, so that the cleaning drive can be automated and the burden on the user can be reduced.

  Note that the ultrasonic motor according to the present embodiment can be modified in the same manner as the ultrasonic motor according to the first embodiment.

  The driving apparatus according to the third embodiment of the present invention is a driving apparatus including the ultrasonic motor according to the first embodiment, and can be applied as a driving apparatus used in a microscope stage, a precision processing apparatus, a semiconductor manufacturing apparatus, and the like. It is.

  FIG. 4 is a diagram schematically illustrating an upper surface of the driving apparatus according to the present embodiment. However, in the figure, for convenience of explanation, a part is shown as a cross section. FIG. 5 is a diagram schematically showing an AA ′ cross section (see FIG. 4) of the driving apparatus according to the present embodiment. FIG. 6 is a diagram schematically illustrating a side surface of the driving apparatus according to the present embodiment as viewed from the ultrasonic motor side.

  As shown in FIGS. 4 to 6, in the driving apparatus according to the present embodiment, a guide member 33a such as a linear guide is provided between a base portion 31 that is a fixed base and a table 32 that is a driven body. , 33b are arranged. One of the guide members 33 a and 33 b is fixed to the base portion 31 and the other is fixed to the table 32. As a result, the table 32 is supported so as to be able to translate in a single axis direction relative to the base portion 31. A sliding member 34 and a scale 35 are fixed to the side surface of the table 32.

  The ultrasonic motor 36 is the ultrasonic motor according to the first embodiment described with reference to FIG. 1, and the driver elements 12 a and 12 b are brought into contact with and pressed against the sliding member 34 provided on the side surface of the table 32. Thus, the holder 13 is fixed to the upper surface of the base portion 31. At this time, by adjusting the screwing amount of the screw 16 inserted into the hole 13c of the holder 13, the grinding wheel 14 for grinding can be arranged and adjusted in a direction perpendicular to the sliding surface of the sliding member 34. Yes. Further, when the grinding wheel 14 is arranged so as to be in contact with or pressed against the sliding member 34, the grinding wheel 14 is configured to contact the sliding member 34 on the surface. ing. At this time, the size of the surface is within a range including a range in which the driver elements 12a and 12b slide on the sliding member 34 during normal driving described later. Grinding) is made possible. With such a configuration, the grinding wheel 14 is brought into contact with and pressed against the sliding member 34 and is separated from the sliding member 34, as well as when the grinding wheel 14 is pressed against the sliding member 34. The pressing force can also be adjusted.

  The driving of the table 32 by the ultrasonic motor 36 is similar to that described in the first embodiment, in which a predetermined drive signal is given to the vibrator 11 from a control device (not shown) to cause elliptical motion in the driver elements 12a and 12b. Is performed by friction between the sliding elements 34 and the driver elements 12a and 12b that perform the elliptical motion.

  An encoder 38 is fixed to the encoder holder 37 fixed to the upper surface of the base portion 31 so as to face the scale 35, and the position of the table 32 can be detected by the scale 35 and the encoder 38. Note that a control device (not shown) is electrically connected to the encoder 38. The encoder 38 is composed of an LED light source and a photodetector, and a grid pattern is printed on the scale 35. The encoder 38 can measure the driving distance of the table 32 by irradiating the scale 35 with light from the LED light source, detecting the reflected light with a photodetector and detecting the lattice pattern of the scale 35. . The scale 34 may be printed with a pattern indicating the origin.

  By performing the closed loop control using the ultrasonic motor, the scale 35, the encoder 38, and the control device, it is possible to perform accurate positioning and speed control of the table 32.

  The drive device according to the present embodiment having such a configuration removes wear powder adhering to the normal drive for driving the table 32 to a desired position and the slide member 34, as described in the first embodiment. Therefore, the cleaning drive for driving the table 32 can be performed.

  In normal driving, the table 32 is driven in a state in which the screwing amount of the screw 16 is adjusted so that the grinding wheel 14 does not contact the sliding member 34. On the other hand, in the cleaning drive, the table 32 is reciprocated in a state in which the screwing amount of the screw 16 is adjusted so that the grinding wheel 14 contacts and is pressed against the sliding member 34.

  In the driving apparatus according to this embodiment, when normal driving is repeatedly performed, the sliding member 34 and the driving elements 12a and 12b are gradually worn, and wear powder generated by the wear gradually adheres to the sliding member 34. However, the abrasion powder adhering to the sliding member 34 can be removed by performing a cleaning drive. The removed wear powder falls as it is, but does not affect the driving of the table 32 thereafter.

  When the cleaning drive is performed, the grinding wheel 14 grinds the sliding member 34 finely, so that the abrasion powder adhering to the sliding member 34 (including the abrasion powder applied to the sliding member 34) is completely obtained. Can be removed. Further, since the grinding wheel 14 is in contact with the sliding member 34 on the surface, there is no possibility that local scratches are generated on the sliding member 34 as in the case of using a hard brush, and the ultrasonic motor 36 is driven. Good characteristics can be maintained.

  The timing for performing the cleaning drive, the number of times to reciprocate the table 32 during the cleaning drive, and the range for reciprocating the table 32 during the cleaning drive are the same as the timing, number of times, and range described in the first embodiment. It can be carried out.

  As described above, according to the drive device according to the present embodiment, the abrasion powder (abrasion as applied to the sliding member 34) adhered to the sliding member 34 by grinding the sliding member 34 itself with the grinding wheel 14. (Including flour) can be completely removed. In addition, it is possible to prevent the drive efficiency and drive performance from being lowered and the life of the ultrasonic motor 36 from being shortened due to the driver elements 12a and 12b biting the wear powder.

The drive device according to this embodiment can be modified as follows.
For example, in this embodiment, the ultrasonic motor according to the first embodiment is applied as the ultrasonic motor 36, but the ultrasonic motor according to the first embodiment is modified (for example, the ultrasonic motor shown in FIG. 2), or the like. It is also possible to apply a modification of the ultrasonic motor according to the second embodiment shown in FIG. 3 or the ultrasonic motor according to the second embodiment.

  Further, for example, in the drive device according to the present embodiment, the LED light source and the light detector are fixed to the encoder holder 37 as a wear powder detector so as to face the sliding member 34, and this is electrically connected to a control device (not shown). It is also possible to configure so as to be connected to each other. In this case, the wear powder detector can detect the accumulation amount of the wear powder by irradiating the sliding member 34 with light from the LED light source and detecting the reflected light with the photodetector. This utilizes the fact that the reflected light gradually weakens as the amount of wear powder accumulated on the sliding member 33 increases. In this case, the ultrasonic motor 36 according to the second embodiment can be combined as the ultrasonic motor 36. In this case, when a predetermined amount of wear powder is detected by the wear powder detector, an electric signal applied to the grindstone seat 21 made of a single-axis piezo element is controlled so that the grinding wheel 14 is applied to the sliding member 34. It is also possible to automatically perform cleaning driving by driving the table 32 after being pressed.

  As mentioned above, although the Example of this invention was described, this invention is not limited to each Example mentioned above, A various improvement and change are possible within the range which does not deviate from the summary of this invention. For example, in each of the above-described embodiments, it is possible to combine configurations according to other embodiments.

DESCRIPTION OF SYMBOLS 11 Vibrator 12a, 12b Driver 13 Holder 13a Notch hole 13b Leaf spring part 13c Hole 14 Grinding wheel 15 Grinding wheel seat 16 Screw 21 Grinding wheel seat 31 Base part 32 Table 33a, 33b Guide member 34 Sliding member 35 Scale 36 Super Sonic motor 37 Encoder holder 38 Encoder

Claims (10)

A vibrator that excites vibrations;
A driver provided in the vibrator;
Holding means for holding the vibrator;
A grinding wheel provided in the holding means;
With
The grinding wheel is configured to be arranged and adjustable.
An ultrasonic motor characterized by that. When the holding means is fixed to the fixed portion so that the driver is brought into contact with and pressed against a sliding member provided on a driven body movably supported with respect to the fixed portion, the grinding The grindstone is configured to be arranged and adjustable in a direction perpendicular to the sliding surface of the sliding member.
The ultrasonic motor according to claim 1. When the grinding wheel is arranged to come into contact with or press against the sliding member, the grinding wheel comes into contact with the sliding member on the surface;
The ultrasonic motor according to claim 2. The grinding wheel is provided on both sides of the vibrator,
The ultrasonic motor according to any one of claims 1 to 3, wherein: In the grinding wheel provided on both sides of the vibrator, the grinding wheel provided on one side is coarse, and the grinding wheel provided on the other side is fine.
The ultrasonic motor according to claim 4. When the driven body is driven in a state where the grindstone with coarse particles is arranged so as to be in contact with and pressed against the sliding member, the grindstone with fine particles is slid. It is arranged so that it does not touch the member,
When the driven body is driven in a state where the grinding wheel with fine particles is arranged so as to be in contact with and pressed against the sliding member, the grinding wheel with coarse particles is slid. Arranged so as not to contact the member,
The ultrasonic motor according to claim 5. The pressing force when the grinding wheel with coarse particles contacts and is pressed against the sliding member, and the pressing force when the grinding wheel with fine particles contacts and presses the sliding member, Different,
The ultrasonic motor according to claim 6. The grinding wheel is configured to be arranged and adjustable by the action of a screw.
The ultrasonic motor according to any one of claims 1 to 7, wherein: The grinding wheel is configured to be arranged and adjustable by the action of a single-axis piezo element.
The ultrasonic motor according to any one of claims 1 to 7, wherein: A base part;
A table supported movably with respect to the base part;
A sliding member provided on the table;
The ultrasonic motor according to any one of claims 1 to 9, provided on the base portion;
With
The holding means of the ultrasonic motor is fixed to the base portion so that the driving element of the ultrasonic motor contacts and is pressed against a sliding member provided on the table,
The grinding wheel is configured to be arranged and adjustable in a direction perpendicular to the sliding surface of the sliding member.
A drive device characterized by that.

Images