JP2005102369A - Driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving device which provides a high driving force and is capable of both the fine feed and coarse feed of a driven body. <P>SOLUTION: The driving device 1 comprises a vibrating body 2. The vibrating body 2 comprises a body part 21 which is bendable, a contact part 23 which is provided on a center axis 31 of the body part 21 and abuts with a driven body P, and an excitation parts 22a-22d which are provided asymmetrically, through the center axis 31, at a position deviated from the center axis 31 of the body part 21 and deform by an applied voltage. A fine feed mode and a normal feed mode are provided. In the fine feed mode, the vibrating body 2 is bent and displaced by the balance of stress generated by one deformation in other words a driving force, and reactive force which the contact part 23 receives from the driven body P after one of the excitation parts 22a and 22c or 22b and 22d is excited. The bending/displacing drives the driven body P through the contact part 23. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a drive device.

As a conventional drive device, a technique described in Patent Document 1 is known. In the conventional driving device, the vibrating body is bent and displaced directly by the excitation unit, thereby driving the driven body via the contact portion.
However, in the conventional driving device in which the vibrator is driven by bending and displacing it directly by the excitation unit, or in which the longitudinal vibration and the bending vibration are used together and resonated at the same time, a large driving force is generated by the vibrator. In order to obtain the above, it is necessary to increase the amplitude of the vibrating body, which increases the driving amount, and it is difficult to feed the driven body slightly (fine movement).

Japanese Patent Laid-Open No. 11-235063

  An object of the present invention is to provide a drive device that can obtain a large driving force and can feed a driven body minutely (finely), and can also feed a driven body roughly (coarsely). is there.

Such an object is achieved by the present invention described below.
The driving device according to the present invention is provided on a bendable main body, a contact portion that is provided on the symmetry axis of the main body portion, abuts on the driven body, and a position off the symmetry axis of the main body portion, A drive device including a vibrating body having a plurality of excitation parts that are deformed by applying a voltage,
By driving at least one of the plurality of excitation units without driving at least one excitation unit and applying a driving force to the other excitation unit, the vibrator receives the contact from the driven body. Bending displacement due to balance with reaction force, and microfeed mode for driving the driven body via the contact portion by this bending displacement,
The driving amount of the driven body in one vibration of the vibrating body has a normal feed mode larger than the minute feed mode.

  According to the present invention, in the minute feed mode, the vibrating body is indirectly bent and displaced by the driving force of the excitation portion and the reaction force received by the contact portion from the driven body, and the bending displacement causes the object to be passed through the contact portion. Drive the driver. As a result, a large driving force can be obtained and the driven body can be finely (finely moved) fed. On the other hand, in the normal feed mode, the driven body can be coarsely (coarsely moved) fed. For this reason, versatility is wide.

In addition, the number of vibrators can be reduced compared to the case where a dedicated vibrator for feeding the driven body minutely and a dedicated vibrator for feeding the vibrator roughly are provided. Can be reduced in size and weight, and the cost can be reduced.
Further, by arranging at least one pair of excitation parts with the symmetry axis (center axis) of the main body interposed therebetween, the vibrating body can be bent in both forward and reverse directions with respect to the symmetry axis. Can be driven in both forward and reverse directions.

The drive device according to the present invention is configured to change the drive direction of the driven body by changing a combination of the excitation unit not driven and the drive excitation unit in the minute feed mode. Is preferred.
Thereby, the drive direction of a to-be-driven body can be changed easily.
The driving device according to the present invention is provided on a bendable main body, a contact portion that is provided on the symmetry axis of the main body portion, abuts on the driven body, and a position off the symmetry axis of the main body portion, A drive device including a vibrating body having a plurality of excitation parts that are deformed by applying a voltage,
By making the distortion amount of at least one excitation part of the plurality of excitation parts different from a reference distortion amount, the vibrating body is bent and displaced, and the driven body via the contact part is caused by the bending displacement. A micro feed mode to drive
The driving amount of the driven body in one vibration of the vibrating body has a normal feed mode larger than the minute feed mode.
According to the present invention, in the minute feed mode, the bending displacement can be induced in the vibrating body due to the deviation (difference) in the distortion amount (expansion / contraction amount) of the excitation unit, so that a higher driving force can be obtained. On the other hand, in the normal feed mode, the driven body can be coarsely (coarsely moved) fed. For this reason, versatility is wide.

In addition, the number of vibrators can be reduced compared to the case where a dedicated vibrator for feeding the driven body minutely and a dedicated vibrator for feeding the vibrator roughly are provided. Can be reduced in size and weight, and the cost can be reduced.
Further, by arranging at least one pair of excitation parts with the symmetry axis (center axis) of the main body interposed therebetween, the vibrating body can be bent in both forward and reverse directions with respect to the symmetry axis. Can be driven in both forward and reverse directions.

The drive device according to the present invention is preferably configured to change the drive direction of the driven body by changing a combination of excitation units that vary the amount of distortion in the micro feed mode.
Thereby, the drive direction of a to-be-driven body can be changed easily.
In the drive device of the present invention, it is preferable that in the minute feed mode, the plurality of excitation units are all driven to drive the driven body.
Thereby, a higher driving force can be obtained.

In the driving device of the present invention, in the minute feed mode, the voltage value applied to the excitation unit is adjusted to make the distortion amount of the corresponding excitation unit different from the reference distortion amount. preferable.
Thereby, the distortion amount of the excitation unit can be easily adjusted (adjusted), and the distortion amount of the corresponding excitation unit can be made different from the reference distortion amount.

In the drive device of the present invention, it is preferable that in the minute feed mode, the displacement direction of the excitation unit is substantially perpendicular to the moving direction of the driven body.
Thereby, the frictional force between the contact portion and the driven body can be increased, and efficient driving can be realized.
In the driving device according to the present invention, it is preferable that longitudinal vibration is excited by the excitation unit in the minute feed mode.
As a result, the displacement amount of the contact portion in the bending direction (lateral direction) can be suppressed as compared with the case where bending vibration or the combined vibration of longitudinal vibration and bending vibration is directly excited on the vibrating body, and the driven body Can be finely fed.

In the drive device of the present invention, it is preferable that the excitation unit is driven at a frequency substantially equal to a resonance frequency of longitudinal vibration in the minute feed mode.
As a result, the displacement amount of the contact portion in the bending direction (lateral direction) can be suppressed as compared with the case where bending vibration or the combined vibration of longitudinal vibration and bending vibration is directly excited on the vibrating body, and the driven body Can be slightly fed, and the driving efficiency can be improved.
In the drive device of the present invention, in the normal feed mode, at least two of the plurality of excitation units are driven to excite at least bending vibration with respect to the vibrating body. Is preferred.

In the drive device of the present invention, it is preferable that the symmetry axis of the main body is substantially perpendicular to the moving direction of the driven body.
Thereby, the frictional force between the contact portion and the driven body can be increased, and efficient driving can be realized.
In the drive device of the present invention, it is preferable that at least one pair of the plurality of excitation portions is disposed with the symmetry axis of the main body portion interposed therebetween.
Thereby, since the vibrating body can be bent in both forward and reverse directions with respect to the symmetry axis, the driven body can be driven in both forward and reverse directions.

In the drive device according to the aspect of the invention, it is preferable that at least one pair of the excitation units among the plurality of excitation units is arranged symmetrically with respect to the symmetry axis of the main body.
As a result, the vibrating body can be bent symmetrically in both forward and reverse directions with respect to the symmetry axis, so that the driven body can be driven symmetrically in both forward and reverse directions.
In the driving apparatus of the present invention, it is preferable that a slit is provided between the pair of excitation units.
Thereby, the restraint between each excitation part is suppressed and the drive efficiency of a vibrating body can be improved.
In the driving apparatus according to the aspect of the invention, it is preferable that the excitation unit includes a piezoelectric element.

DESCRIPTION OF EMBODIMENTS Hereinafter, a drive device of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
(First embodiment)
FIG. 1 is a perspective view showing a drive device according to a first embodiment of the present invention, and FIG. 2 is a configuration diagram showing the drive device shown in FIG.
As shown in these drawings, the drive device 1 includes the vibrating body 2 and a control system having a drive circuit 41. The drive device 1 vibrates the vibrating body 2 by applying an alternating voltage (high frequency voltage), and transmits the vibration to the driven body (moving body) P to drive (move) the driven body P. It is. In the driving device 1, the vibration component of the vibrating body 2 in the driving direction (moving direction) of the driven body P is suppressed, so that the driven body P can be slightly displaced, that is, can be moved slightly (fine movement). The driven body P can be coarsely (coarsely moved) by making the driving amount (feed amount) of the driven body P in one vibration of the vibrating body 2 larger (larger) than in the fine feed mode. It is characterized in that it has a normal feed (coarse feed) mode.

The vibrating body 2 is in contact with a bendable main body (reinforcing plate) 21, a first excitation unit 22a, a second excitation unit 22b, a third excitation unit 22c, and a fourth excitation unit 22d. A portion (convex portion) 23 and a pair of support portions (arm portions) 24 are provided. Hereinafter, the first excitation unit, the second excitation unit, the third excitation unit, and the fourth excitation unit are also simply referred to as “excitation units”, respectively.
The main body 21 has a substantially rectangular plate-like structure and is made of, for example, stainless steel, aluminum, an aluminum alloy, titanium, a titanium alloy, copper, a copper-based alloy, or other metal materials. However, the shape and constituent materials of the main body 21 are not limited to this. The main body 21 has a function of reinforcing the vibrating body 2 and prevents damage to the vibrating body 2 due to over-amplitude or external force. The main body 21 functions as a common electrode for a pair of deformation elements (electric / mechanical conversion elements) 25 described later.

Each excitation part 22a, 22b, 22c, 22d is comprised with the deformation | transformation element 25 and the electrode 26, respectively, and has a function which excites the vibration of the vibrating body 2 (excitation). Specifically, in the portion of the deformation element 25, the portion that expands and contracts (stretching vibration) by application of voltage and the electrode 26 are the main portions of the excitation portions 22a, 22b, 22c, and 22d, respectively. That is, in this drive device 1, of the deformation element 25, the portion where each electrode 26 is disposed (the portion corresponding to each electrode 26) and the corresponding electrode 26 are respectively provided in the excitation units 22 a, 22 b, 22 c, The main part of 22d is comprised.
Here, the “deformation element” refers to an element having a member or part that is deformed by the supply of electric energy. Examples of such a deformable element include a piezoelectric element, a shape memory element, a magnetostrictive element, and an artificial muscle. Among these, a piezoelectric element is preferable. In the driving device 1, a piezoelectric element is employed as the deformation element 25.

  The constituent material of the piezoelectric element is not particularly limited. For example, lead zirconate titanate (PZT), crystal, lithium niobate, barium titanate, lead titanate, lead metaniobate, polyvinylidene fluoride, lead zinc niobate Various types such as lead scandium niobate can be used. By applying an alternating voltage to the piezoelectric element, the piezoelectric element expands and contracts in a predetermined direction. Further, the expansion / contraction displacement can be easily and arbitrarily controlled by adjusting (adjusting) the magnitude and frequency of the applied voltage. Thereby, the deformation of the deformation element 25 can be easily and accurately controlled.

  The deformation element 25 has a rectangular plate-like structure substantially congruent with the main body portion 21. The deformation elements 25 are configured as a pair, and are laminated so as to be planar with the main body 21 so as to face each other and sandwich the main body 21 from the front and back sides (see FIG. 1). . Further, the deformation elements 25, 25 are fixed to the main body 21. Thereby, there exists an advantage which can improve the intensity | strength of the vibrating body 2. FIG.

The electrode 26 is composed of a strip-shaped (rectangular) plate-like member, and is installed as a set of four pieces on one deformation element 25 along the edge on the long side on the deformation element 25. ing. The installed electrodes 26 are respectively included in the first excitation unit 22a, the second excitation unit 22b, the third excitation unit 22c, and the fourth excitation unit 22d.
Each electrode 26 is provided at a position deviated from the longitudinal central axis (symmetric axis) 31 of the vibrating body 2 (main body portion 21), and is disposed substantially parallel to the central axis 31. (See FIGS. 1 and 2). Thereby, bending vibration is excited (excited) in the vibrating body 2 by the action described later.

  These electrodes 26 are symmetrical via a central axis 31 and via a central axis (symmetric axis) 32 in a direction (width direction) perpendicular to the longitudinal direction of the vibrating body 2 (main body portion 21). Are symmetrically arranged (see FIGS. 1 and 2). That is, on the vibrating body 2, the first excitation unit 22a and the second excitation unit 22b are provided symmetrically with the central axis 31 interposed therebetween, and the third excitation unit 22c and the fourth excitation unit 22d. Are provided symmetrically with the central axis 31 in between, and the first excitation part 22a and the third excitation part 22c are provided symmetrically with the central axis 32 in between, and the second excitation part 22b and the fourth excitation part 22d are provided symmetrically with the central axis 32 in between. Thereby, symmetrical vibrations are excited in the vibrator 2 when the first excitation unit 22a is driven and when the second excitation unit 22b is driven. Similarly, the case where the third excitation unit 22c is driven, the case where the fourth excitation unit 22d is driven, the case where the first excitation unit 22a is driven, and the case where the third excitation unit 22c is driven. When the second excitation unit 22b is driven and when the fourth excitation unit 22d is driven, mutually oscillating vibrations are excited in the vibrator 2.

  Further, a total of eight electrodes 26 are provided for each of the front and back deformation elements 25, 25. As a result, the first excitation unit 22a, the second excitation unit 22b, the third excitation unit 22c, and the fourth excitation unit 22d are formed on the front and back of the vibrating body 2, respectively. However, illustration of the first excitation unit 22a, the second excitation unit 22b, the third excitation unit 22c, and the fourth excitation unit 22d on the back surface side that does not appear in the drawing is omitted.

In this drive device 1, the vibrating body 2 has a total of eight excitation parts 22a, 22a, 22b, 22b, 22c, 22c, 22d, and 22d on the front and back sides, which are provided with excitation parts 22a, 22b, Compared to the case of having 22c and 22d, it is preferable in that a stronger driving force can be obtained.
However, the present invention is not limited to this, and the excitation units 22 a, 22 b, 22 c, and 22 d may be provided only on one side surface of the vibrating body 2. Thereby, the vibrating body 2 (drive device 1) can be reduced in thickness and weight.
Further, the electrodes 26 and 26 of the first excitation parts 22a and 22a on the front and back sides, the electrodes 26 and 26 of the second excitation parts 22b and 22b on the front and back sides, the electrodes 26 of the third excitation parts 22c and 22c on the front and back sides, 26 and the electrodes 26 and 26 of the fourth excitation portions 22d and 22d on the front and back sides are electrically connected to each other by a conductive wire (conductive wire) (see FIGS. 1 and 2).

  Further, the electrodes 26 of the respective excitation units 22a, 22b, 22c, and 22d are connected to the drive circuit 41 of the vibrating body 2 (see FIGS. 1 and 2). The drive circuit 41 applies an alternating voltage to the excitation units 22a, 22b, 22c, and 22d to cause the excitation units 22a and 22b to expand and contract at high speed, thereby adjusting the applied voltage, that is, adjusting the magnitude and frequency of the applied voltage. The expansion / contraction displacement of the portions 22a, 22b, 22c, and 22d is freely controlled.

In this case, in the minute feed mode, only the excitation unit of one combination of the first excitation unit 22a and the third excitation unit 22c, and the second excitation unit 22b and the fourth excitation unit 22d is driven. (Energize) Further, in the normal feed mode, only the excitation units of one combination of the first excitation unit 22a and the fourth excitation unit 22d, and the second excitation unit 22b and the third excitation unit 22c are driven. Accordingly, the drive circuit 41 excites vibrations in the vibrating body 2 and controls the vibrations.
Note that a detection circuit (not shown) for detecting the vibration frequency (vibration) of the vibrating body 2 by detecting a voltage from the excitation unit on the non-drive side (the non-energized side) may be provided.

  In the driving device 1, switches (switching switches) S 1, S 2, and S 3 are provided between the vibrating body 2 and the driving circuit 41. The switch S1 is for switching the driving direction between the forward direction (right direction in FIG. 2) and the reverse direction (left direction in FIG. 2), and the switching is as shown in FIG. Further, the switches S2 and S3 are for switching the mode between the fine feed mode and the normal feed mode, and are linked to each other, and the switching is as shown in FIG. In addition, each switch S1-S3 can employ | adopt arbitrary structures, respectively.

  The contact part 23 is provided in the center part of the short side of the vibrating body 2, that is, the center part of the tip part in the longitudinal direction. Further, the contact portion 23 is disposed on the central axis 31 of the vibrating body 2, protrudes in the direction of the central axis 31, and comes into contact with the driven body P substantially vertically (see FIGS. 1 and 2). The contact portion 23 is formed integrally with the main body portion 21 (the main body portion 21 and the contact portion 23 are formed as one member). Thereby, there exists an advantage which can install the contact part 23 firmly with respect to the main-body part 21 (vibrating body 2). In particular, in the driving device 1, the contact portion 23 collides with the driven body P at a high speed and repeatedly with a high pressing force due to the vibration of the vibrating body 2 during driving. Therefore, this configuration has an advantage that the durability of the contact portion 23 can be improved.

  In the present embodiment, the contact portion 23 has a substantially semicircular tip (see FIGS. 1 and 2). Such a contact portion 23 stably makes frictional contact with the side surface of the driven body P as compared with the case where the contact portion 23 has a square tip portion. Accordingly, there is an advantage that the pressing force from the vibrating body 2 can be reliably transmitted to the driven body P even when the acting direction of the vibrating body 2 is slightly deviated. Note that the shape of the contact portion 23 is not limited to a semicircular shape, and may be another shape.

  Here, the positional relationship between the excitation units 22a to 22d and the contact unit 23 will be described. In this drive device 1, the excitation vibrations 22 a to 22 d and the contact part 23 are indirectly induced in the vibrating body 2 by the expansion and contraction of predetermined excitation parts of the excitation parts 22 a to 22 d. It is provided at the position. Specifically, as described above, each of the excitation units 22a to 22d is provided at a position deviated from the central axis 31 of the vibrating body 2, is substantially parallel to the central axis 31, and has a predetermined value. The excitation parts are arranged so as to be symmetrical with each other via the central axis 31 (see FIGS. 1 and 2).

On the other hand, the contact portion 23 is disposed on the central axis 31 of the vibrating body 2, protrudes in the direction of the central axis 31, and makes contact with the driven body P substantially perpendicularly.
In such an arrangement, when the driving device 1 is not driven (stationary), the longitudinal direction of the excitation units 22a to 22d, that is, the extension line in the expansion / contraction direction, serves as a contact point (contact point) between the contact unit 23 and the driven body P. I can't pass. Therefore, in this configuration, as will be described later, the stress caused by the expansion / contraction of the excitation parts 22a and 22c or the stress caused by the expansion / contraction of the excitation parts 22b and 22d and the reaction force that the contact part 23 receives from the driven body P are vibrations. Acting on the body 2, bending motion (flexural vibration) is induced in the vibrating body 2. As a result, there is an advantage that minute bending vibration can be excited in the vibrating body 2. Further, for example, by adjusting the applied voltage to the excitation units 22a to 22d and adjusting the positional relationship between the excitation units 22a to 22d and the contact portion 23, the bending vibration excited by the vibrating body 2 is adjusted with a small amount. There are advantages you can do. Specifically, the bending vibration can be adjusted by, for example, increasing or decreasing (changing) the applied voltage, increasing or decreasing the frequency, increasing or decreasing the distance between the excitation units 22a to 22d and the center axis 31 of the vibrating body 2, and the like.

Each support portion 24 is provided so as to protrude substantially perpendicularly to the long side at the center portion of the corresponding long side of the vibrating body 2, that is, the central portion of the side portion in the longitudinal direction. Each support portion 24 is formed integrally with the main body portion 21 (the main body portion 21 and each support portion 24 are formed as one member). Thereby, there exists an advantage which can install the support part 24 firmly with respect to the main-body part 21 (vibrating body 2). For example, bolts, screws, and other fixing means (not shown) are inserted through holes provided at the ends of the support portions 24, and are fixedly installed on a casing (base) (not shown) via the fixing means. Each support portion 24 supports the vibrating body 2 in a state of being separated from the wall surface (not shown) of the casing (floating with respect to the wall surface). In such a configuration, since no friction is generated between the vibrating body 2 and the wall surface of the housing, there is an advantage that the vibration of the vibrating body 2 is not easily restrained and free vibration of the vibrating body 2 can be realized.
Each support portion 24 has elasticity, and the elastic body (restoring force) urges the vibrating body 2 toward the driven body P, and the urging force causes the contact portion 23 of the vibrating body 2 to be urged. Is pressed (pressed) against the side surface of the driven body P. The main body 21 is grounded through the support 24, for example.

  Here, the support portion 24 is provided on the side of the vibrating body 2 and at a position that is a node of vibration of the vibrating body 2. This position can be obtained by vibration analysis or other known methods. For example, when the electrodes 26 are provided symmetrically in the longitudinal direction and the width direction of the vibrating body 2 as in the driving device 1 (see FIGS. 1 and 2), the longitudinal direction of the vibrating body 2 is substantially reduced. Near the center is a vibration node. Therefore, in the driving device 1, the support portion 24 is provided at the approximate center of the long side of the vibrating body 2. With this configuration, when the vibrating body 2 vibrates, the support portion 24 does not hinder the vibration of the vibrating body 2, so that dissipation of vibration energy from the support portion 24 to the outside can be suppressed. Thereby, there exists an advantage which can drive the drive device 1 efficiently.

In this first embodiment, the driven body P is a slider and is slidable (movable) in a direction perpendicular to the central axis 31 of the vibrating body 2 (the x-axis direction in FIGS. 1 and 2). is set up.
In the present invention, the configuration of the driven body P is not limited to this, and the driven body P includes, for example, a plate-like body, a linear body, a rod-like body, a columnar body, a cylindrical state, a rotor (rotary body), An annular body, a spherical body, etc. may be sufficient, and the to-be-driven body P may be provided, for example so that rotation is possible or rocking | swinging about a predetermined fulcrum.

  3 and 4 are explanatory views showing the operation of the driving apparatus shown in FIG. FIGS. 3A to 3C show the case where the driven body P slides in the right direction in the micro feed mode, and FIG. 3D shows the case where the driven body P is driven in the micro feed mode. The case where the body P slides in the left direction in the figure is shown. 4A shows a case where the driven body P slides in the right direction in the drawing in the normal feeding mode, and FIG. 4B shows the driven body P in the normal feeding mode. The case of sliding to the left in the middle is shown.

In this drive device 1, when setting to the minute feed mode in which the driven body P is minutely (finely moved), the switches S2 and S3 are switched to the “minute” side in FIG.
Further, when the driven body P is driven (slid) in the right side (positive direction) in FIGS. 2 and 3, the switch S1 is switched to the “positive direction” side in FIG.
Then, the vibrating body 2 applies an AC voltage having a predetermined frequency (high frequency) from the drive circuit 41 to the first excitation unit 22a and the third excitation unit 22c. As a result, the first excitation unit 22a and the third excitation unit 22c (specifically, the deformation element 25 in the portion where the electrode 26 is disposed) are rapidly and repeatedly applied in the longitudinal direction by the application of the AC voltage. It expands and contracts. The expansion / contraction displacement (vibration) of the first excitation unit 22a and the third excitation unit 22c itself is longitudinal vibration without bending. At this time, the second excitation portion 22b and the fourth excitation portion 22d side do not expand or contract, or are extremely small due to the expansion and contraction of the first excitation portion 22a and the third excitation portion 22c. I do.

  First, from the initial state where the vibrating body 2 is not deformed (see FIG. 3A), the first excitation portion 22a and the third excitation portion 22c extend in the longitudinal direction. At this time, the stress generated by the extension of the first excitation portion 22a and the third excitation portion 22c and the reaction force received by the contact portion 23 from the driven body P act in the vibration body 2 and the vibration body 2 Is bent in a direction in which the central axis 31 is curved so that the left side in the figure is convex (see FIG. 3B). The pressing force L (displacement of the contact portion 23) L exerted on the driven body P by the contact portion 23 acts in a direction inclined with respect to a direction perpendicular to the moving direction of the driven body P (vertical direction). A pressure component (component in the moving direction of the driven body P in the displacement of the contact portion 23) Lx is generated in the moving direction of the body P. On the other hand, the pressing component Lz in the vertical direction of the pressing force L (the vertical component in the displacement of the contact portion 23) Lz generates a frictional force between the contact portion 23 and the driven body P. Thereby, the driven body P slides in the right direction (positive direction) in FIG. 3B by the pressing component Lx in the moving direction and the pressing component Lz in the vertical direction given from the contact portion 23.

Next, the first excitation part 22a and the third excitation part 22c contract, and the vibrating body 2 bends in the opposite direction (see FIG. 3C). At this time, the contact portion 23 is instantaneously separated from the driven body P, and does not inhibit the driven body P from sliding in the right direction and does not slide the driven body P in the left direction.
By repeatedly expanding and contracting the first excitation unit 22a and the third excitation unit 22c in the vibration body 2, the vibration body 2 alternately repeats the states of FIG. 3B and FIG. 3C. As a result, bending vibration is induced in the vibrating body 2 as a result (indirectly), and the contact portion 23 performs a slight rotational motion in a counterclockwise elliptical orbit in the drawing. Then, the driven body P is sent in the right direction in the figure by the pressing force L from the contact portion 23. As described above, in the driving device 1, the vibration body 2 is indirectly coupled with the longitudinal vibration excited by the first excitation portion 22 a and the third excitation portion 22 c and the reaction force received by the contact portion 23 due to the longitudinal vibration. In this case, bending vibration is induced to drive the driven body P.
Here, the drive frequency of the vibrating body 2 is preferably the resonance frequency of the longitudinal vibration. As a result, there is an advantage that the driving efficiency can be improved and a larger driving force can be obtained. The resonance frequency can be determined as appropriate based on the shape, structure, material, and other factors of the vibrating body 2.

On the other hand, in contrast to the above case, when the driven body P is driven (slid) in the left direction (reverse direction) in FIGS. 2 and 3, the switch S1 is on the “reverse direction” side in FIG. Switch to.
Then, the vibrating body 2 applies an AC voltage having a predetermined frequency from the drive circuit 41 to the second excitation unit 22b and the fourth excitation unit 22d.
Thereby, the contact part 23 of the vibrating body 2 performs a slight rotational motion in the clockwise elliptical orbit in the figure by the same action as described above. And the to-be-driven body P is sent to the left direction (reverse direction) in a figure with the pressing force from this contact part 23 (refer FIG.3 (d)).

  Here, in the minute feed mode, the stress generated by the expansion and contraction of the first excitation unit 22a and the third excitation unit 22c, or the second excitation unit 22b and the fourth excitation unit 22d, that is, the first excitation unit. The vibrating body 2 is balanced by the balance between the driving force of the part 22a and the third excitation part 22c, or the second excitation part 22b and the fourth excitation part 22d, and the reaction force that the contact part 23 receives from the driven body P. Indirectly induces bending vibration and generates (forms) a pressing component Lx in the moving direction of the driven body P, so that the pressing component Lx in the moving direction is suppressed to a very small amount, and the driven body P becomes a very small amount. Is displaced, that is, a slight (fine movement) is fed.

Further, since the pressing component Lx in the moving direction is suppressed to a very small amount, the pressing component Lz in the direction perpendicular to the moving direction of the driven body P is large. Thereby, a big frictional force is obtained between the contact part 23 and the driven body P, and a high driving force is obtained. In particular, since the excitation parts 22a to 22d (that is, the deformation element 25) themselves excite longitudinal vibration, the pressing component Lz in the vertical direction is very large and the driving force of the driven body P is very high.
In this way, the driven body P can be arbitrarily driven in both forward and reverse directions (both left and right directions in the figure). In other words, the moving direction of the driven body P can be changed by changing the switch S1 and changing the driving excitation section (the combination of the driving section that is not driven and the driving excitation section). Can be moved in either the forward direction or the reverse direction.

  In the driving device 1, the excitation units 22 a and 22 c and the excitation units 22 b and 22 d are formed symmetrically with respect to the central axis 31 of the vibrating body 2. As a result, the vibrating body 2 is mutually connected when the first excitation unit 22a and the third excitation unit 22c are driven and when the second excitation unit 22b and the fourth excitation unit 22d are driven. Therefore, there is an advantage that the driven body P can be moved forward and backward equally (forward and backward symmetrical). That is, since it is forward / reverse (right / left) symmetric, the drive characteristics in the forward direction and the drive characteristics in the reverse direction can be made substantially equal.

When the normal feed (coarse feed) mode in which the driven body P can be coarsely (coarsely moved) is set, the switches S2 and S3 are switched to the “normal” side in FIG. When the driven body P is driven (slid) on the right side (positive direction) in FIGS. 2 and 3, the switch S1 is switched to the “positive direction” side in FIG.
The vibrating body 2 is applied with an AC voltage having a predetermined frequency from the drive circuit 41 to the first excitation unit 22a and the fourth excitation unit 22d.

Thereby, as shown in FIG. 4A, the first excitation unit 22a and the fourth excitation unit 22d are driven (expanded / contracted), and the vibration body 2 is subjected to bending vibration (or longitudinal vibration and bending vibration). Compound vibration) is excited. That is, bending vibration (or combined vibration of longitudinal vibration and bending vibration) is directly generated in the vibrator 2.
Thereby, the contact part 23 of the vibrating body 2 performs a slight rotational motion in a counterclockwise elliptical orbit in the drawing. And the to-be-driven body P is sent to the right direction in a figure with the pressing force from this contact part 23. FIG.

On the other hand, in contrast to the above case, when the driven body P is driven (slid) in the left direction (reverse direction) in FIGS. 2 and 3, the switch S1 is on the “reverse direction” side in FIG. Switch to.
Then, the vibrating body 2 applies an AC voltage having a predetermined frequency from the drive circuit 41 to the second excitation unit 22b and the third excitation unit 22c.
As a result, as shown in FIG. 4B, the second excitation unit 22b and the third excitation unit 22c are driven (expanded / contracted), and the vibration body 2 is subjected to bending vibration (or longitudinal vibration and bending vibration). Compound vibration) is excited. That is, bending vibration (or combined vibration of longitudinal vibration and bending vibration) is directly generated in the vibrator 2.
Thereby, the contact part 23 of the vibrating body 2 performs a slight rotational motion in a clockwise elliptical orbit in the drawing. And the to-be-driven body P is sent to the left direction in a figure with the pressing force from this contact part 23. FIG.

Here, in this normal feed mode, since the driven body P is driven by exciting (exciting) bending vibration directly by the excitation section, the pressing component Lx in the moving direction is not suppressed, and the driven body P Is displaced by a relatively large amount, that is, coarsely (coarsely moved). Further, by increasing the amplitude of the bending vibration, each of the pressing component Lx in the moving direction of the driven body P and the pressing component Lz in the direction perpendicular to the moving direction of the driven body P can be increased. The driven body can be roughly fed with a large driving force.
In this way, the driven body P can be arbitrarily driven in both forward and reverse directions (both left and right directions in the figure).

As described above, the driving device 1 has the fine feed mode and the normal feed mode. Therefore, in the fine feed mode, the driven body P is slightly (finely moved) with a large (high) driving force. The driven body P can be coarsely (coarsely moved) with a large driving force in the normal feed mode.
By selecting the minute feed mode, the driven body P can be minutely fed and positioning with high accuracy becomes possible.

On the other hand, by selecting the normal feed mode, the driven body P can be roughly fed (high-speed feed) and can be moved in a short time.
In particular, in the minute feed mode, the pressure component Lx in the moving direction of the driven body P is adjusted by adjusting the voltage applied to the excitation units 22a to 22d and adjusting the positional relationship between the excitation units 22a to 22d and the contact portion 23. By adjusting, the displacement amount of the driven body P can be adjusted in minute units.

  In the minute feed mode, the contact portion 23 of the vibrating body 2 can be largely displaced in the vertical direction (the height direction with respect to the contacted surface of the driven body P) by the longitudinal vibration of the excitation portions 22 to 22d. . Therefore, for example, even when the surface roughness of the driven body P is large, the contact portion 23 can easily get over the unevenness, and thus stable driving can be realized.

  Further, in the driving device 1, the vibrating body 2 is arranged with the vibration direction (displacement direction) of the excitation portions 22a to 22d oriented substantially perpendicular to the moving direction of the driven body P (FIG. 1). And FIG. 2). Therefore, in the minute feed mode, the pressing component Lz in the moving direction of the driven body P can be reduced and larger than the configuration in which the vibrating body is arranged so that the vibration direction is inclined with respect to the driven body. A driving force (high driving force) can be obtained.

In the minute feed mode, the excitation units 22a to 22d of the vibrating body 2 are all driven by longitudinal vibration, so that the vibration body 2 can be driven by setting the frequency substantially equal to the resonance frequency of the longitudinal vibration as the driving frequency. It can be driven efficiently.
Moreover, in this drive device 1, the structure of the vibrating body 2 is simple, and the drive device 1 can be reduced in size and weight.

Moreover, in this drive device 1, since the single vibrating body 2 is used and the micro feed mode and the normal feed mode are switched by switching the energization pattern of the vibrator 2, the driven body P is used for micro feed. Compared with the case where a dedicated vibrating body and a dedicated vibrating body for coarse feeding are provided, the number of vibrating bodies can be reduced, and the drive device 1 can be reduced in size and weight. Cost can be reduced.
Thus, since this drive device 1 has the micro feed mode and the normal feed mode, the versatility is wide.

The use of the drive device 1 is not particularly limited, but the drive device 1 has a minute feed mode in which the driven body P can be minutely fed with a large driving force as described above. It can be suitably used for operating devices (control devices) and electronic devices that require force and fine feed. Specific examples of this include an electric stage, a turntable of an imaging device (camera), and the like.
In addition, although the vibrating body in this embodiment has four excitation parts (electrodes) on one side and has a total of eight exciting parts, in the present invention, the configuration of the vibrating body (for example, the overall shape) The shape of the main body, the shape of the excitation part (electrode), the number of excitation parts, the arrangement of the excitation parts, etc.), the driving method of the vibrating body (for example, vibration mode, energization pattern, etc.) are limited to this. It is not a thing.

  For example, in the vibrating body 2 shown in FIG. 1, the fifth excitation 22a and the third excitation 22c and the second excitation 22b and the fourth excitation 22d, that is, on the central axis 31, By providing excitation and driving the fifth excitation in the normal feed mode, the composite vibration of the longitudinal vibration and the bending vibration is excited, so that the vibrating body 2 performs the composite vibration of the longitudinal vibration and the bending vibration. It may be configured. In this case, it is preferable that the resonance frequency of the longitudinal vibration and the resonance frequency of the bending vibration are different from each other and are close to each other.

(Second Embodiment)
Next, a second embodiment will be described.
FIG. 5 is a configuration diagram showing a driving apparatus according to the second embodiment of the present invention.
Hereinafter, the driving apparatus 1 according to the second embodiment will be described with a focus on differences from the first embodiment described above, and description of similar matters will be omitted.

In the second embodiment shown in the figure, in the minute feed mode, for all the excitation parts of the first excitation part 22a, the second excitation part 22b, the third excitation part 22c, and the fourth excitation part 22d, Drive by applying AC voltage.
Further, in the driving device 1, switches (switching switches) S4, S5, S6, S7, S8, S9, S10, S11, and S12 are provided between the vibrating body 2 and the driving circuit 41, respectively. The switch S4 is for switching the driving direction between the forward direction (right direction in FIG. 5) and the reverse direction (left direction in FIG. 5) in the normal feed mode. The switching is as shown in FIG. It is. In addition, the switches S5 and S6 are for switching the driving direction between the forward direction (right direction in FIG. 5) and the reverse direction (left direction in FIG. 5) in the minute feed mode, respectively. The switching is as shown in FIG. Further, the switches S7 to S12 are for switching the mode between the fine feed mode and the normal feed mode, and are interlocked with each other, and the switching is as shown in FIG. Note that any configuration can be adopted for each of the switches S4 to S12.
In addition, the switch S7 is connected to the high (High) AC voltage side of the drive circuit 41, and the switch S8 is connected to the low (Low) AC voltage side of the drive circuit 41. The high AC voltage and the low AC voltage of the drive circuit 41 are AC voltages having the same frequency and the same phase.

In the minute feed mode, the excitation unit of one combination of the first excitation unit 22a and the third excitation unit 22c and the second excitation unit 22b and the fourth excitation unit 22d is connected to the high AC voltage side. The other combination of the excitation units is connected to the low AC voltage side, and these are driven by AC voltages of different magnitudes.
On the other hand, in the normal feed mode, only the excitation unit of one combination of the first excitation unit 22a and the fourth excitation unit 22d and the second excitation unit 22b and the third excitation unit 22c has a high AC voltage. Only one combination of excitation units is driven. Since this normal feed mode is the same as that of the first embodiment described above, only switching of the switch will be described.

FIG. 6 is an explanatory diagram showing the operation of the drive device described in FIG.
In this drive device 1, when setting to the minute feed mode in which the driven body P is minutely (finely moved), the switches S7 to S12 are switched to the “minor” side in FIG.
Further, when the driven body P is driven (slid) on the right side (positive direction) in FIG. 5, the switches S5 and S6 are switched to the “positive direction” side in FIG.

  The vibrator 2 applies an alternating voltage of a predetermined frequency (high frequency) from the drive circuit 41 to the first excitation unit 22a, the second excitation unit 22b, the third excitation unit 22c, and the fourth excitation unit 22d. To be applied. In this case, a high AC voltage is applied to the first excitation unit 22a and the third excitation unit 22c, and a low AC voltage is applied to the second excitation unit 22b and the fourth excitation unit 22d.

  Thereby, as shown in FIG. 6, these excitation parts 22a-22d are all expanded-contracted in a longitudinal direction, and are longitudinally vibrated. However, since the first excitation unit 22a and the third excitation unit 22c are applied with a higher voltage than the second excitation unit 22b and the fourth excitation unit 22d, the first excitation unit 22a and the third excitation unit 22a. The amount of deformation, that is, the amount of expansion / contraction (distortion amount) is larger in the excitation unit 22c than in the second excitation unit 22b and the fourth excitation unit 22d. Bends and vibrates. And the to-be-driven body P is sent to the right direction (forward direction) in the figure with the pressing force L from the contact part 23. FIG.

On the other hand, contrary to the above case, when the driven body P is driven (slid) in the left direction (reverse direction) in FIG. 5, the switches S5 and S6 are moved to the “reverse direction” side in FIG. Switch.
The vibrator 2 applies an alternating voltage of a predetermined frequency (high frequency) from the drive circuit 41 to the first excitation unit 22a, the second excitation unit 22b, the third excitation unit 22c, and the fourth excitation unit 22d. To be applied. In this case, a high AC voltage is applied to the second excitation unit 22b and the fourth excitation unit 22d, and a low AC voltage is applied to the first excitation unit 22a and the third excitation unit 22c. The driven body P is sent in the left direction in the figure.
Note that either the distortion amount of the excitation unit when the low AC voltage is applied or the distortion amount of the excitation unit when the high AC voltage is applied may be set as the reference distortion amount. In addition, an arbitrary distortion amount between the distortion amount of the excitation unit when the low AC voltage is applied and the distortion amount of the excitation unit when the high AC voltage is applied may be set as a reference distortion amount. Good.

  In this way, by adjusting the magnitude (voltage value) of the alternating voltage applied to the excitation units 22a to 22d, the distortion amount of the corresponding excitation unit is made different from the reference distortion amount, so that the excitation unit 22a can be easily obtained. The distortion amount of ˜22d can be adjusted (adjusted), and the distortion amount of the corresponding excitation unit can be made different from the reference distortion amount. That is, the distortion amount of the first excitation unit 22a and the third excitation unit 22c is easily made larger than the distortion amount of the second excitation unit 22b and the fourth excitation unit 22d, or the second excitation unit The distortion amount of 22b and the 4th excitation part 22d can be made larger than the distortion amount of the 1st excitation part 22a and the 3rd excitation part 22c. Then, by switching the switches S5 and S6, the moving direction of the driven body P can be changed by changing the large (small) excitation unit (combination of the excitation units that vary the distortion amount) with a large amount of distortion. The driven body P can be moved in either the forward direction or the reverse direction.

When the normal feed (coarse feed) mode in which the driven body P can be coarsely (coarsely moved) is set, the switches S7 to S12 are switched to the “normal” side in FIG. When the driven body P is driven (slid) on the right side (positive direction) in FIG. 5, the switch S4 is switched to the “positive direction” side in FIG.
The vibrating body 2 is applied with an AC voltage having a high predetermined frequency from the drive circuit 41 to the first excitation section 22a and the fourth excitation section 22d, and the driven body is the same as in the first embodiment described above. P is sent in the right direction in the figure.

On the other hand, contrary to the above case, when the driven body P is driven (slid) in the left direction (reverse direction) in FIG. 5, the switches S5 and S6 are moved to the “reverse direction” side in FIG. Switch.
Then, the vibrator 2 is applied with an AC voltage having a predetermined frequency from the drive circuit 41 to the second excitation unit 22b and the third excitation unit 22c. Sent left.

According to this drive device 1, the same effect as the drive device 1 of 1st Embodiment mentioned above is acquired.
And in this drive device 1, in the micro feed mode, since all the excitation parts of the excitation parts 22a-22d are driven (excited) and induced flexural vibration, compared with the drive apparatus 1 of the first embodiment, A larger driving force can be obtained.

  Further, in the driving device 1, the magnitude of bending (bending rate) of the vibrating body 2 is determined by the voltage applied to the first excitation unit 22 a and the third excitation unit 22 c, the second excitation unit 22 b, and the second excitation unit 22 c. 4 is regulated by the difference from the voltage applied to the excitation unit 22d (voltage difference between the excitation units 22a and 22b). Therefore, by adjusting the voltage difference between the excitation units 22 a and 22 b, the amount of movement of the driven body P due to one vibration of the vibrating body 2 can be easily adjusted.

  Further, even if the voltage difference between the excitation units 22a and 22b is reduced and the amount of movement of the driven body P due to one vibration of the vibrating body 2 is small, a large AC voltage is applied to each excitation unit 22a to 22d itself. Since it can be applied, the pressing component Lz applied in the vertical direction can be increased. Therefore, a sufficiently large frictional force can be applied between the contact portion 23 and the driven body P, a larger driving force can be obtained, and the driving efficiency of the driven body P can be further increased.

(Third embodiment)
Next, a third embodiment will be described.
FIG. 7 is a configuration diagram showing a vibrating body of the drive device according to the third embodiment of the present invention.
Hereinafter, the driving device 1 of the third embodiment will be described focusing on the differences from the first embodiment described above, and the description of the same matters will be omitted.

As shown in the figure, in the third embodiment, the vibrating body 2 has a slit 27. The slit 27 is provided between the first excitation unit 22 a and the third excitation unit 22 c and the second excitation unit 22 b and the fourth excitation unit 22 d, that is, on the central axis 31 of the vibrating body 2. The main body 21 and the deformation element 25 are cut out by the slit 27. That is, the first excitation unit 22 a and the third excitation unit 22 c, and the second excitation unit 22 b and the fourth excitation unit 22 d are separated on the vibrating body 2 by the slit 27.
In this case, as shown in FIG. 7A, the slit 27 may be opened at the end portion on the opposite side (upper side in the drawing) of the vibrating body 2, and FIG. As shown in FIG.

According to this drive device 1, the same effect as the drive device 1 of 1st Embodiment mentioned above is acquired.
And in this drive device 1, all the excitation parts 22a-22d to which the voltage was applied are expanded and contracted substantially independently without being restrained by the other excitation part. That is, the interference between the first excitation unit 22a and the third excitation unit 22c and the second excitation unit 22b and the fourth excitation unit 22d is suppressed, and the excitation units 22a to 22d to which the voltage is applied are , Both are easily expanded and contracted, thereby improving the driving efficiency of the vibrator 2.
The third embodiment can be applied to each embodiment.

The drive device of the present invention has been described based on the illustrated embodiment. However, the present invention is not limited to this, and the configuration of each part is replaced with an arbitrary configuration having the same function. be able to. In addition, any other component may be added to the present invention.
Further, the present invention may be a combination of any two or more configurations (features) of the above embodiments.
In the present invention, the drive device may have a plurality of vibrating bodies. In this case, for example, the plurality of vibrating bodies may be configured to drive a common driven body, and the plurality of vibrating bodies are configured to drive separate driven bodies, respectively. May be.

It is a perspective view which shows the drive device concerning 1st Embodiment of this invention. It is a block diagram which shows the drive device described in FIG. It is explanatory drawing which shows the effect | action of the drive device described in FIG. It is explanatory drawing which shows the effect | action of the drive device described in FIG. It is a block diagram which shows the drive device concerning 2nd Embodiment of this invention. It is explanatory drawing which shows the effect | action of the drive device described in FIG. It is a block diagram which shows the vibrating body of the drive device concerning 3rd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Drive device 2 ... Vibrating body 11 ... Base 21 ... Main-body part 22a-22d ... Excitation part 23 ... Contact part 24 ... Supporting part 25 ... Deformation element 26 ... Electrode 27 ... Slit 31, 32 ... Center axis 41 ... Drive circuit L ... Pressing force Lx ... Pressing component Lz ... Pressing component P ... Driven body S1 to S12 ... Switch

Claims (15)

Deformable by applying a voltage to a bendable main body, a contact portion provided on a symmetry axis of the main body portion, a contact portion contacting the driven body, and a position deviating from the symmetry axis of the main body portion. A driving device including a vibrating body having a plurality of excitation units,
By driving at least one of the plurality of excitation units without driving at least one excitation unit and applying a driving force to the other excitation unit, the vibrator receives the contact from the driven body. Bending displacement due to balance with reaction force, and microfeed mode for driving the driven body via the contact portion by this bending displacement,
A driving apparatus comprising: a normal feed mode in which a drive amount of the driven body in one vibration of the vibrator is larger than the minute feed mode.   2. The drive device according to claim 1, wherein in the minute feed mode, the drive direction of the driven body is changed by changing a combination of the excitation unit that is not driven and the excitation unit that is driven. 3. . Deformable by applying a voltage to a bendable main body, a contact portion provided on a symmetry axis of the main body portion, a contact portion contacting the driven body, and a position deviating from the symmetry axis of the main body portion. A driving device including a vibrating body having a plurality of excitation units,
By making the distortion amount of at least one excitation part of the plurality of excitation parts different from a reference distortion amount, the vibrating body is bent and displaced, and the driven body via the contact part is caused by the bending displacement. A micro feed mode to drive
A driving apparatus comprising: a normal feed mode in which a drive amount of the driven body in one vibration of the vibrator is larger than the minute feed mode.   4. The drive device according to claim 3, wherein in the minute feed mode, the drive direction of the driven body is changed by changing a combination of excitation units that vary the amount of distortion. 5.   5. The drive device according to claim 3, wherein in the minute feed mode, the plurality of excitation units are all driven to drive the driven body. 6.   6. The micro feed mode is configured so that a distortion amount of a corresponding excitation unit is made different from a reference distortion amount by adjusting a voltage value applied to the excitation unit. The drive device described.   The driving apparatus according to claim 1, wherein in the minute feed mode, a displacement direction of the excitation unit is substantially perpendicular to a moving direction of the driven body.   The drive device according to any one of claims 1 to 7, wherein in the minute feed mode, the excitation unit is configured to excite longitudinal vibration.   The drive device according to any one of claims 1 to 8, wherein in the minute feed mode, the excitation unit is driven at a frequency substantially equal to a resonance frequency of longitudinal vibration.   10. The device according to claim 1, wherein, in the normal feed mode, at least two excitation units among the plurality of excitation units are driven to excite at least bending vibration with respect to the vibrating body. The drive device described in 1.   The drive device according to claim 1, wherein a symmetry axis of the main body is substantially perpendicular to a moving direction of the driven body.   The drive device according to any one of claims 1 to 11, wherein at least one pair of excitation units among the plurality of excitation units is disposed with a symmetry axis of the main body portion interposed therebetween.   The drive device according to any one of claims 1 to 11, wherein at least one pair of the excitation units among the plurality of excitation units is arranged symmetrically with respect to an axis of symmetry of the main body unit.   The drive device according to claim 12 or 13, wherein a slit is provided between the pair of excitation units.   The drive device according to claim 1, wherein the excitation unit includes a piezoelectric element.

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