JP4078466B2 - Vibration actuator driving device and lens barrel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vibration actuator driving device in which a vibration actuator and a relative motion member perform relative motion including rotational motion, and a lens barrel using the vibration actuator drive device.
[0002]
[Prior art]
In a lens barrel, various actuators are incorporated for various purposes such as focus adjustment of a photographing optical system, change of focal length, and control of a diaphragm. Conventionally, a lens barrel incorporating a vibration actuator is known as one of such lens barrels. The vibration actuator has characteristics such as good control characteristics, quietness, and high torque. In the lens barrel, the vibration actuator is used as a power source of an automatic focus adjustment mechanism, for example. The vibration actuator is also used as a power source for electrically adjusting the focal length of the zoom lens barrel, so-called power zoom. As an example of a lens barrel using a vibration actuator as a power source for power zoom, for example, an annular vibration actuator (hereinafter referred to as “annular vibration actuator”) disclosed in Japanese Patent Application Laid-Open No. 59-111117. There is a lens barrel used.
[0003]
The annular vibration actuator is a rotary vibration actuator that outputs a rotational driving force. In addition to this, there is a linear vibration actuator that outputs a straight driving force. For example, “Linear vibration actuator for the purpose of optical pickup movement” (Yoshiro Tomikawa et al .: Proceedings of the 5th Dynamic Symposium on Electromagnetic Forces pp393-398) Are listed. A linear vibration actuator is composed of a plate-like elastic body and an electromechanical conversion element joined to the elastic body. An AC voltage is applied to the electromechanical conversion element to vibrate the elastic body, and the elastic body vibrates longitudinally. And bending vibration are generated in a harmonic manner to generate an elliptical motion on the elastic body surface.
[0004]
Japanese Patent Laid-Open No. 8-2111279 discloses a lens barrel that also incorporates such a linear vibration actuator. That is, in the lens barrel disclosed in Japanese Patent Application Laid-Open No. 8-21279, an annular vibration actuator is built in to drive a focus adjustment lens group that adjusts the focus, and a focal length adjustment lens that adjusts the focal length. A linear vibration actuator is built in to drive the group.
[0005]
FIG. 10 is a cross-sectional view of a lens barrel disclosed in Japanese Patent Laid-Open No. 8-2111279. As shown in FIG. 10, in the lens barrel disclosed in Japanese Patent Application Laid-Open No. 8-21279, an annular vibration actuator 210 is arranged on the outer peripheral side of the focus adjustment lens group L201. The annular vibration actuator 210 includes a stator 211 and a rotor 212, and the rotary cylinder 202 is rotationally driven by the rotational motion of the rotor 212. The rotational movement of the rotary cylinder 202 is transmitted to the frame body 206 of the focus adjustment lens group L201 via the key groove 202a and the key 206a, whereby the frame body 206 rotates integrally with the rotary cylinder 202. Further, the rotational movement of the frame body 206 is converted into a linear movement in the optical axis direction by the helicoid 209 coupled to the fixed cylinder 201. As a result, the frame 206 and the focus adjustment lens group L201 move in the optical axis direction.
[0006]
On the other hand, a linear vibration actuator 205 is disposed on the outer peripheral side of the focal length adjusting lens unit L202. The vibration actuator 205 is in contact with a flat portion 207a provided on the outer peripheral surface of the frame body 207. When the vibration actuator 205 is driven, a driving force in the optical axis direction is applied to the flat portion 207a. As a result, the frame body 207 and the focal length adjusting lens group L202 are arranged in parallel with the optical axis, and are guided by the linear guide 208 penetrating the frame body 207 to move in the optical axis direction.
As described above, in the lens barrel disclosed in Japanese Patent Application Laid-Open No. 8-21279, the focus adjustment lens group is driven by the annular vibration actuator, and the focal length adjustment lens group is directly driven in the optical axis direction by the linear vibration actuator. ing.
[0007]
[Problems to be solved by the invention]
However, the conventional lens barrel described above has the following problems.
First, when the photographic optical system frame is directly driven in the optical axis direction using a linear vibration actuator, the positioning accuracy of the frame is the minimum distance that the vibration actuator can move the frame. (Hereinafter referred to as “drive unit”). Therefore, there is a problem that the accuracy of focusing adjustment or focal length adjustment cannot be improved beyond the drive unit of the linear vibration actuator.
In addition, when driving the frame of the photographing optical system using an annular vibration actuator, a helicoid mechanism or the like is disposed between the vibration actuator and the frame of the photographing optical system. There is no problem with accuracy.
However, in the ring-type vibration actuator, high surface accuracy is required on the contact surfaces of both the stator and the rotor. This surface accuracy is not particularly problematic for a small vibration actuator, but in a vibration actuator used in a lens barrel, the stator and rotor have a large diameter that is about the same as the diameter of the lens barrel. There is a problem that it is difficult to ensure appropriate surface accuracy.
[0008]
On the other hand, a linear type vibration actuator has a plurality of driving force extraction parts formed in a protrusion shape on the abdomen of flexural vibration, and this driving force extraction part (hereinafter also referred to as a protrusion part) is formed in the width direction. Have a spread. Therefore, when the driven member is a rotating body, the relative motion speed of the protrusion varies depending on the location. For this reason, sound and heat may be emitted from the sliding surface of the rotating body and the protrusion.
For this reason, the vibration actuator may fall down when the protrusion is simply made small, and cannot stably make frictional contact with the rotating body.
In addition, linear vibration actuators are designed so that the dimensional ratio between the length direction and the thickness direction is almost constant in order to generate longitudinal vibration and bending vibration harmoniously. The space efficiency was poor for those having a small inner / outer diameter ratio and long in the direction of the rotation axis.
[0009]
The first problem of the present invention is that the sliding surface between the vibration actuator and the relative motion member can be stably brought into frictional contact without generating sound or heat, and the inner / outer diameter ratio is small, and the rotational axis direction It is another object of the present invention to provide a vibration actuator driving apparatus having a high space efficiency for a long object.
A second problem of the present invention is a lens barrel that drives a focus adjustment lens group and the like using a vibration actuator, and has a structure in which the positioning accuracy of the focus adjustment lens group and the like is high and high surface accuracy is not required. The lens barrel is provided.
[0010]
[Means for Solving the Problems]
In order to solve the above problems, the invention of claim 1 A vibrator having a driving force extraction portion provided on the outer periphery; Symmetrical stretching vibration that expands and contracts within a given plane and non-axisymmetric vibration In the drive force extraction part Vibration actuator for generating driving force and the vibration actuator The driving force extraction part In contact with Said Relative to vibration actuator rotation Do exercise Toroidal Relative motion member and A pressurizing mechanism for pressurizing the driving force extraction portion to the relative motion member from a direction substantially parallel to a rotation axis in the relative rotational motion; Comprising relative There is provided a vibration actuator driving apparatus in which a direction of a rotation axis in a rotational motion is substantially parallel to the predetermined surface and substantially orthogonal to a vibration direction of the non-axisymmetric vibration.
[0011]
According to a second aspect of the present invention, in the vibration actuator driving device according to the first aspect, Vibrator Is formed in a plate shape And The vibrator is provided with an opening including the center of the vibrator on the predetermined surface, and the pressurizing mechanism is in the vicinity of the opening of the vibrator. With pressure Provided is a vibration actuator driving device that operates.
[0012]
According to a third aspect of the present invention, in the vibration actuator driving device according to the second aspect, the pressurizing mechanism contacts the vibrator at a thickness portion of the vibrator in the opening, and the pressure is applied to the contact surface. Provided is a vibration actuator driving device that operates.
[0013]
According to a fourth aspect of the present invention, in the vibration actuator driving device according to the second or third aspect, the opening is formed with a plane portion substantially parallel to the vibration direction of the non-axisymmetric vibration, and The pressure mechanism is a vibration actuator driving device that contacts the vibrator at the thickness portion of the vibrator in the plane portion and presses the vibrator toward the relative motion member by applying the pressure to the contact surface. I will provide a.
[0014]
According to a fifth aspect of the present invention, in the vibration actuator driving device according to any one of the first to fourth aspects, the vibrator is moved in a direction intersecting with a plane including the vibration of the symmetrical extension vibration. Provided is a vibration actuator driving device including a position regulating member for regulating.
[0015]
According to a sixth aspect of the present invention, the support unit supports at least a part of the optical system and is movable in the direction of the optical axis of the optical system, and is described in any one of the first to fifth aspects. A vibration actuator driving device; and a conversion unit that converts a rotational movement around the optical axis into a linear movement in the optical axis direction and transmits the linear movement to the support unit. The vibration actuator driving device includes: A rotating part that can rotate around an optical axis is configured, and the vibration actuator rotationally drives the rotating part by frictional contact with a part of the rotating part, or is provided in the rotating part, A lens mirror that rotationally drives the rotating unit by frictional contact with a part of another member facing the rotating unit, and the converting unit converts the rotational motion of the rotating unit into a linear motion in the optical axis direction. Provide a tube.
[0016]
According to a seventh aspect of the present invention, in the lens barrel according to the sixth aspect of the present invention, the lens barrel further includes a fixed barrel that accommodates the vibration actuator, and the vibration actuator includes a lens barrel that is accommodated within a thickness of the fixed barrel. provide.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments according to the present invention will be described in more detail with reference to the drawings.
In the following description, an ultrasonic actuator using an ultrasonic vibration region is taken as an example of the vibration actuator. In addition, parts having the same functions as those of the above-described conventional example are given common reference numerals or unified reference numerals at the end thereof, and redundant descriptions are appropriately omitted.
[0018]
(Embodiment of vibration actuator driving device)
1 is a perspective view showing an embodiment of a vibration actuator driving apparatus according to the present invention, FIG. 2 is a schematic view showing the vibration actuator according to the embodiment of FIG. 1, and FIG. 3 is a vibration according to the embodiment of FIG. It is a conceptual diagram which shows the vibration form of an actuator.
The vibration actuator driving device of this embodiment includes a rotating body (relative motion member) 140 and an ultrasonic actuator 110.
[0019]
As shown in FIG. 2A, the ultrasonic actuator 110 includes a vibrator 111 formed of a donut-plate-like piezoelectric element that is an electromechanical transducer that converts electrical energy into mechanical displacement, and one surface of the vibrator 111. And the two half-doughnut plate-like electrodes 112 and 113 arranged symmetrically with respect to the center line CL, and the driving force provided at the outer periphery of the vibrator 111 and intersecting the center line CL. A take-out section 114 and the like.
[0020]
The vibrator 111 has a (R, 1) mode [FIG. 3 (a)] which is a symmetrical extension vibration in the radial direction (plane direction) and a ((1, 1)) mode which is a non-axisymmetric in-plane bending vibration. The dimensional ratio is such that [FIG. 3B] occurs simultaneously.
[0021]
As shown in FIG. 2B, the drive circuit 120 that drives the ultrasonic actuator 110 includes an oscillator 121 that outputs an AC voltage drive signal having a predetermined frequency, and a phase of the drive signal generated from the oscillator 121 by 90 °. A phase shifter 122 to convert, an amplifier 123 that amplifies the drive signal from the oscillator 121 and connects to the A terminal, an amplifier 124 that amplifies the drive signal from the phase shifter 122 and connects to the B terminal, and the like It has.
[0022]
When the ultrasonic actuator 110 inputs signals having a phase difference of 90 degrees to the two electrodes 112 and 113 shown in FIG. 2A, the two modes become vibrations having a phase difference of 90 degrees, and the driving force is extracted. An elliptical motion is generated in the portion 114. If the rotating body 140, which is a relative motion member, is brought into pressure contact with the driving force extraction portion 114, it is possible to cause relative motion between the ultrasonic actuator 110 and the rotating body 140.
[0023]
As shown in FIG. 3, the ultrasonic actuator 110 includes an expansion / contraction surface of a symmetrical extension vibration generated in the vibrator 111 (the expansion / contraction direction of the driving force extraction unit 114 is indicated by an arrow A) and the rotation axis O of the rotating body 140. The axial direction (see FIG. 1) is substantially parallel. Further, the vibration direction (arrow B) of the non-axisymmetric vibration ((1, 1)) mode is substantially orthogonal to the axial direction of the rotation axis O of the rotating body 140, and the rotational tangential direction T of the rotating body 140 (FIG. 1). Is substantially the same.
Here, if the vibration in the (R, 1) mode and the vibration in the ((1, 1)) mode are generated at the same time, the driving force extraction unit 114 may cause an elliptical motion to rotate the rotating body 140. it can. At this time, the vibration direction in the ((1, 1)) mode and the circumferential direction (tangential direction) of the rotational motion substantially coincide with each other, so that force can be transmitted efficiently.
[0024]
According to the present embodiment, the ultrasonic actuator 110 using symmetric elongation vibration and non-axisymmetric vibration is employed, and the axial direction of the rotation axis of the rotating body 140 is set to the expansion / contraction surface of the symmetric elongation vibration generated in the vibrator 111. Since it is substantially parallel and substantially orthogonal to the vibration direction of the non-axisymmetric vibration, it is possible to realize a driving situation in which sound is hardly generated during driving and force transmission efficiency is good.
[0025]
(First embodiment of lens barrel)
FIG. 4 is a diagram showing a first embodiment of a lens barrel using the vibration actuator driving device according to the present invention.
In the lens barrel of FIG. 4, the ultrasonic actuator 110 </ b> B is disposed in the accommodating portion 151 provided within the thickness t of the fixed barrel 150 of the lens barrel. At this time, the expansion / contraction surface of the symmetrical extension vibration generated in the vibrator 111 of the ultrasonic actuator 110B and the axial direction of the rotation axis O of the rotating body 140B are substantially parallel, and the vibration direction of the non-axisymmetric vibration and the rotation It arrange | positions so that the axial direction of the rotating shaft O of the body 140B may be substantially orthogonal. The rotational force of the rotating body 140B is transmitted to the moving mechanism of the moving lens that moves for focusing, zooming, and the like.
[0026]
According to this embodiment, it is possible to improve the space efficiency for a lens barrel having a small inner / outer diameter ratio and long in the direction of the rotation axis.
[0027]
(Second embodiment of lens barrel)
FIG. 5 is a diagram showing a second embodiment of a lens barrel using the vibration actuator driving device according to the present invention, FIG. 6 is an enlarged view of the vibrator of FIG. 5, and FIGS. FIG. 6 is a view showing a support pressurizing mechanism of the vibration actuator driving device of FIG.
[0028]
The lens barrel of the present embodiment includes an ultrasonic actuator 110C, a fixed cylinder 150C having an accommodating portion 151 for accommodating the ultrasonic actuator 110C, a support member 132 that supports the ultrasonic actuator 110C, and an optical axis. A rotating body 140C that is rotatably supported, and a pressure member 133 that pressurizes and contacts the ultrasonic actuator 110C and the rotating body 140C are provided.
[0029]
As shown in FIG. 6, the ultrasonic actuator 110 </ b> C is formed on a vibrator 111 </ b> C composed of a piezoelectric element having an almost circular outer shape and an opening 115 at the center, and one plane of the vibrator 111 </ b> C. Two electrodes 112 and 113 arranged symmetrically in a state of being separated from each other with respect to the line CL, a driving force extracting portion 114 provided at a position on the outer periphery of the vibrator 111C and intersecting the center line CL, and the like It consists of The opening 115 includes a circular portion 115a formed substantially concentrically with the vibrator 111C, and two cutout portions 115b formed in a rectangular shape at two opposite locations on the circumference of the circular portion 115a. .
[0030]
The accommodating portion 151 is formed on the outer surface side of the fixed cylinder 150C so as to have a substantially rectangular cutout shape, and accommodates the ultrasonic actuator 110C within the thickness t of the fixed cylinder 150C.
[0031]
The support member 132 includes a support pin 132a (see FIG. 7B) attached to the ceiling portion 151a of the accommodating portion 151, an L-shaped arm portion 132b provided at the tip of the support pin 132a, and an arm portion 132b. A pressing plate portion 132c (see FIG. 8A) that is inserted into the opening 115 of the vibrator 111C and presses the flat portion of the notch 115b of the vibrator 111C, and a pressing plate portion 132c. On the other hand, it is detachable with a screw or the like, and includes a fixing portion 132e for fixing the pressing plate portion 132c inserted into the opening 115 so as not to come off.
[0032]
The arm portion 132b is provided so as to be movable in the axial direction of the support pin 132a. As shown in FIG. 8B, the pressing plate portion 132c is inserted into the opening 115 of the vibrator 111C, and presses the flat portion of the notch 115b on the lower surface (region indicated by P in FIG. 8). It has become.
[0033]
As shown in FIGS. 7A and 8A, the pressing plate portion 132c and the fixing portion 132e are respectively along a direction parallel to the contact surface between the driving force extraction portion 114 and the rotating body 140. The arm portions are formed in two directions from the center side of the vibrator 111C toward the outer peripheral side. A protrusion 111C (position restricting member) 132d (FIG. 7) for sandwiching the vibrator 111C at the tip of each arm portion and preventing blurring (movement with the BB line in FIG. 5 as a rotation axis) is provided. (A) and FIG. 8 (a)) are formed. In other words, the vibrator 111C is sandwiched between the protrusion 132d on the pressing plate portion 132c side and the protrusion 132d on the fixed portion 132e side, so that the coupling between the vibrator 111C and the support member 132 and the vibration of the vibrator 111 are prevented. Prevention is done.
[0034]
The pressing member 133 includes a coil spring inserted into the support pin 132a, and presses the driving force extraction member 114 against the rotating body 140 via the pressing member 132c by pressing the upper plate 132b ′ of the arm portion 132b downward. To do. The coil spring presses the driving force extraction portion 114 against the rotating body 140 with a predetermined pressure when the length of the spring is equal to the distance between the ceiling of the accommodating portion 151 and the upper plate 132b ′ of the arm portion 132b. Is set to
[0035]
When incorporating the ultrasonic actuator 110C into the lens barrel, first, the support pin 132a of the support member 132 is fixed to the ceiling portion 151a of the accommodating portion 151 of the fixed cylinder 150C with the coil spring as the pressure member 133 attached. To do. At this time, the fixing portion 132e of the support member 132 is removed from the pressing plate portion 132c. Further, the support member 132 is arranged in such a direction that the arm portion 132b is close to the inner wall surface of the accommodating portion 151. Thereafter, the vibrator 111C of the ultrasonic actuator 110C is disposed in the housing portion 131 such that the pressing plate portion 132c is inserted into the opening 115 thereof. Finally, the fixing portion 132e of the support member 132 is fixed to the pressing plate portion 132c with a screw or the like.
[0036]
According to the lens barrel of the present embodiment, the ultrasonic actuator 110C, the support part 132, and the pressure member 133 can be accommodated in the thickness portion of the fixed cylinder 150C in a space-efficient manner.
In addition, since the support member 132 presses the vibrator 111C in contact with the thickness portion (planar portion) of the notch 115b, stable pressure support is possible.
Furthermore, since the vibrator 111C is regulated from both sides, it can be stably supported and efficient vibration can be achieved.
[0037]
(Third embodiment of lens barrel)
FIG. 9 is a cross-sectional view showing a third embodiment of the lens barrel according to the present invention.
The frame body 166 is a member that holds the focus adjustment lens group L161. The frame body 166 is coupled to the fixed cylinder 161 by a helicoid 169. A rotary cylinder 162 is rotatably attached in front of the optical axis of the fixed cylinder 161. A key groove 162a is formed on the inner periphery of the rotary cylinder 162 in parallel with the optical axis. A key 166a is formed on the frame 166 of the focus adjustment lens unit L1, and the key 166a is engaged with the key groove 162a.
[0038]
A rotor 140 </ b> D is integrally fixed to an end of the rotating cylinder 162 at the rear of the optical axis. The rotor 140D has a flat portion 140D-1 that intersects perpendicularly to the optical axis behind the optical axis. Further, the rotor 140D has a circumferential groove 140D-2 on the outer peripheral surface. A sphere 141 is spread over the circumferential groove 140D-2. The ball 141 is a member that brings the rotor 140 into rolling contact with the fixed cylinder 161 to ensure smooth rotation of the rotor 140D. In front of the optical axis of the sphere 141, a holding ring 164 is screwed into the inner peripheral side of the fixed cylinder 161. The restraining ring 164 is a member that restricts movement of the sphere 141 in the optical axis direction. Due to the action of the restraining ring 164, the ball 141 does not jump out of the lens barrel after the lens barrel is assembled. In addition, the restraining ring 164 restricts movement of the rotor 140 </ b> D in the optical axis direction together with the sphere 141.
[0039]
A driving force extraction portion 114 of the ultrasonic actuator 110D is disposed behind the optical axis of the rotor 140D so as to be in contact with the flat portion 140D-1.
The ultrasonic actuator 110D is the same as that shown in FIG. 5, the support member 132 and the pressure member 133 are the same as those shown in FIGS. 5 to 8, and the vibrator 111 is connected to the flat portion 140D-1 of the rotor 140D. Pressurize in the direction of.
[0040]
The frame body 167 is a member that holds the focal length adjusting lens group L162. The frame body 167 has through-holes 167a and 167b (not shown because 167b overlaps with the 167a) formed in the thick portion in parallel to the optical axis direction, and a flat portion 167c is formed in a part of the outer periphery. ing.
A linear guide 168 is inserted into the through hole 167a (167b). The linear guide 168 is disposed in parallel with the optical axis, and is fixed to the fixed cylinders 161 and 163.
[0041]
A linear vibration actuator 165 is disposed at a position facing the flat portion 167 c of the frame body 167. The vibration actuator 165 mainly includes a vibrator 165a and a pressure member 165b.
[0042]
As described above, in this embodiment, a rotational driving force is applied to the rotor 140D using the ultrasonic actuator 110D. Further, the rotational movement of the rotor 140D is converted into a linear movement in the optical axis direction by the helicoid 169 and then used for driving the focus adjustment lens group L161. Therefore, in the present embodiment, the positioning accuracy of the focus adjustment lens unit L161 in the optical axis direction is mainly determined by the characteristics of the helicoid 169. In other words, in the present embodiment, the positioning accuracy of the focusing lens group L161 is improved by appropriately determining the shape of the helicoid 169 regardless of the drive unit size of the ultrasonic actuator 110D, and high-precision focusing adjustment is performed. Can be done.
[0043]
Further, since the ultrasonic actuator 110D contacts only a part of the rotor 140D, there is an advantage that the flat portion 140D-1 does not require very strict flatness. In general, in a vibration actuator such as an ultrasonic motor, the amplitude of vibration generated in a vibrator is on the order of microns. Therefore, a flatness requirement for a moving element (rotor) that makes frictional contact with the vibrator and moves relatively is severe. In addition, the demand for flatness increases with increasing contact area between the vibrator and the moving element. Therefore, if an annular ultrasonic motor is employed as in the lens barrel disclosed in Japanese Patent Application Laid-Open No. 59-111117, the ultrasonic motor and the rotor are in contact with each other all around the rotor. Therefore, the flatness requirement for the rotor becomes very strict. On the other hand, in the present embodiment, a linear ultrasonic actuator is adopted and is brought into contact with only a part of the rotor 140D. Therefore, the flatness of the rotor is determined by the driving force extracting portion of the ultrasonic actuator 110D. All that is required is a guarantee in a relatively narrow area corresponding to the thickness of 114. Therefore, as described above, the flatness requirement for the flat portion 140D-1 of the rotor 140D is relatively moderate, and its manufacture is easy.
[0044]
(Deformation)
The present invention is not limited to the embodiment described above, and various modifications and changes are possible, and these are also within the scope of the present invention.
For example, although the driving force extraction unit 114 has been described with an example in which a protrusion is formed, a friction material may be bonded.
The relative motion member is not limited to an annular member, and may be any member that has a trajectory including a rotational motion, such as a rotation within 360 °, or a motion that changes the curvature of a circle. .
In each embodiment of the lens barrel, an example has been described in which one ultrasonic actuator is provided, but a plurality of, for example, three ultrasonic actuators may be provided.
[0045]
【The invention's effect】
As described above, according to the invention described in each claim, the direction of the rotational axis in the rotational motion of the relative motion member is substantially parallel to the expansion / contraction surface of the symmetrical extension vibration generated in the vibrator, and the vibrator Therefore, the generation of sound during driving is reduced, and the transmission efficiency of force can be improved.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a vibration actuator driving device according to the present invention.
FIG. 2 is a schematic diagram showing a vibration actuator according to the embodiment of FIG. Fig.1 (a) is the front view and top view which show the structure of the vibrator | oscillator of a vibration actuator. FIG. 1B is a block diagram showing the configuration of the drive circuit of the vibration actuator.
FIG. 3 is a schematic view showing a vibration form of the vibration actuator according to the embodiment of FIG. 1; FIG. 3A shows a vibration form of the (R, 1) mode that is symmetric elongation vibration, and FIG. 3B shows a vibration form of the ((1, 1)) mode that is non-axisymmetric vibration. FIG.
FIG. 4 is a schematic view showing the configuration of a first embodiment of a lens barrel incorporating a vibration actuator driving device according to the present invention. FIG. 4A is a schematic diagram illustrating a cross section of a side surface cut by a plane parallel to the XZ plane, and FIG. 4B is a schematic diagram illustrating an arrangement state of the rotating body and the vibration actuator in the XY plane. FIG. 4C is a schematic view showing a cross section of a side surface cut by a plane parallel to the XZ plane.
FIG. 5 is a schematic diagram showing a second embodiment of a lens barrel incorporating a vibration actuator driving device according to the present invention. Fig.5 (a) is a perspective view, FIG.5 (b) is the elements on larger scale of the (b) part of Fig.5 (a).
6 is an enlarged view showing the vibrator of FIG. 5. FIG.
7 is a schematic view showing a pressurizing form of the vibration actuator driving device of FIG. 5. FIG. FIG. 7A shows a cross section taken along the line AA in FIG. 5, and FIG. 7B shows a cross section taken along the line BB in FIG.
8 is a schematic view showing a configuration of a pressurizing mechanism of the vibration actuator driving device of FIG. FIG. 8A is a schematic perspective view showing the configuration of the contact portion with the vibrator. FIG. 8B is a cross-sectional view taken along the line C-C in FIG.
FIG. 9 is a schematic diagram showing a third embodiment of a lens barrel incorporating a vibration actuator driving device according to the present invention.
FIG. 10 is a schematic diagram showing a lens barrel incorporating a vibration actuator driving device according to a conventional example.
[Explanation of symbols]
110 Ultrasonic actuator
111 vibrator
112,113 electrodes
114 Driving force extraction part
132 Support member
133 Pressure member
140 Rotating body (relative motion member)
150 fixed cylinder

Claims (7)

Has a vibrator driving force output portion is provided on the outer periphery, driving the symmetrical elongation vibrations stretch within a predetermined plane to the vibrator, the driving force output portion harmonically generate a non-axisymmetric vibration A vibration actuator that generates force,
A relative motion member annular shape to perform relative rotational movement between said contact with the driving force output portion of the vibration actuator, the vibration actuator,
A pressurizing mechanism for pressurizing the driving force extraction portion to the relative motion member from a direction substantially parallel to a rotation axis in the relative rotational motion ;
A vibration actuator driving apparatus characterized in that a direction of a rotation axis in the relative rotational motion is substantially parallel to the predetermined plane and substantially orthogonal to a vibration direction of the non-axisymmetric vibration. The vibration actuator driving device according to claim 1,
The vibrator is formed in a plate shape,
The vibrator is provided with an opening including the center of the vibrator on the predetermined surface,
The vibration actuator driving apparatus characterized in that the pressurizing mechanism applies a pressing force in the vicinity of the opening of the vibrator.   3. The vibration actuator driving device according to claim 2, wherein the pressurizing mechanism is in contact with the vibrator at a thickness portion of the vibrator in the opening, and the pressure is applied to the contact surface. Vibration actuator drive device.   4. The vibration actuator drive device according to claim 2, wherein a planar portion substantially parallel to a vibration direction of the non-axisymmetric vibration is formed in the opening, and the pressurizing mechanism includes the planar portion. The vibration actuator driving device according to claim 1, wherein a thickness portion of the vibrator contacts the vibrator, and the pressure is applied to the contact surface to press the vibrator toward the relative motion member.   5. The vibration actuator drive device according to claim 1, further comprising a position restriction member that restricts movement of the vibrator in a direction intersecting with a plane including the vibration of the symmetrical extension vibration. A vibration actuator drive device characterized by that.   A support unit that supports at least a part of the optical system and is movable in the direction of the optical axis of the optical system, the vibration actuator driving device according to any one of claims 1 to 5, A converter that converts rotational motion about the optical axis into linear motion in the direction of the optical axis and transmits the linear motion to the support portion, and the vibration actuator driving device is capable of rotating the relative motion member about the optical axis. The rotating actuator is configured to rotate and drive the rotating unit by frictional contact with a part of the rotating unit, or another rotating unit that is provided in the rotating unit and faces the rotating unit. A lens barrel, wherein the rotating unit is rotationally driven by frictional contact with a part of a member, and the converting unit converts a rotational motion of the rotating unit into a linear motion in the optical axis direction.   7. The lens barrel according to claim 6, further comprising a fixed cylinder that accommodates the vibration actuator, wherein the vibration actuator is accommodated within a thickness of the fixed cylinder.

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