JPH11275878A - Vibration actuator driving device and lens-barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably bring a rotating body into frictional contact with an ultrasonic actuator without causing sound or heart to be generated from the sliding surface, and at the same time, to improve the spatial efficiency of the vibration actuator drive device for such a body that has a small inside/outside diameter ratio and is long in the direction of axis of rotation. SOLUTION: A vibration actuator drive device is provided with an ultrasonic actuator 110B, which harmoniously generates a symmetrical extensional vibration (R, 1) mode and a non-axisymmetric vibration (1, 1) mode and a rotating body 140 which comes into contact with the actuator 110B with pressure and causes at least part of the actuator 110B to make relative motions including revolving motions. The vibrating direction of the actuator 110B in the symmetrical extensional vibration (R, 1) mode nearly coincides with the axial direction of the revolving motions of the rotating body 140.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field 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 same.

[0002]

2. Description of the Related Art In a lens barrel, various actuators are incorporated for various purposes such as focus adjustment of a photographing optical system, change of a focal length, and control of an aperture. Conventionally, there has been known a lens barrel having a built-in vibration actuator. The vibration actuator has features such as good control characteristics, quietness, and high torque, and is used in a lens barrel as a power source of, for example, an automatic focusing mechanism. Further, the vibration actuator is also used as a power source of a so-called power zoom for electrically adjusting a focal length in a zoom lens barrel. As an example of a lens barrel using a vibration actuator as a power source of a power zoom, for example, a ring-shaped vibration actuator (hereinafter, referred to as a “ring-shaped vibration actuator”) disclosed in JP-A-59-111117 is used. There is a lens barrel used.

The above-mentioned annular vibration actuator is a rotary vibration actuator that outputs a rotational driving force. In addition to the above, there is a linear vibration actuator that outputs a linear driving force. The configuration and load characteristics of the linear vibration actuator are described in, for example, "Piezoelectric Linear Motor for Moving Optical Pickup" (Yoshiaki Tomikawa et al .: Proceedings of the 5th Dynamic Symposium on Electromagnetic Force, pp 393-398). Are listed. A linear vibration actuator is made up of a flat elastic body and an electromechanical transducer joined to the elastic body, and applies an AC voltage to the electromechanical transducer to vibrate the elastic body, causing the elastic body to vibrate vertically. And an elliptical motion are generated on the surface of the elastic body by generating the vibration and the bending vibration in harmony.

Japanese Patent Application Laid-Open No. Hei 8-21279 discloses a lens barrel that also incorporates such a linear vibration actuator. That is, JP-A-8-21127
In the lens barrel disclosed in No. 9, an annular vibration actuator is built in to drive a focus adjustment lens group for adjusting a focal point, and a linear actuator is driven to drive the focal length adjustment lens group for adjusting a focal length. Built-in vibration actuator.

FIG. 10 is a sectional view of a lens barrel disclosed in Japanese Patent Application Laid-Open No. 8-21279. As shown in FIG. 10, in the lens barrel disclosed in Japanese Patent Application Laid-Open No. Hei 8-21279, an annular vibration actuator 210 is arranged on the outer peripheral side of the focusing lens group L201. The annular vibration actuator 210 includes a stator 211 and a rotor 212, and the rotary cylinder 202 is driven to rotate by the rotation of the rotor 212. The rotational movement of the rotating barrel 202 is transmitted to the frame 206 of the focusing lens group L201 via the key groove 202a and the key 206a, whereby the frame 206 rotates integrally with the rotating barrel 202. Further, the rotational motion of the frame 206 is converted into a linear motion in the optical axis direction by the helicoid 209 connected to the fixed cylinder 201. As a result, the frame 206 and the focus adjustment lens group L201 move in the optical axis direction.

On the other hand, a linear vibration actuator 205 is arranged on the outer peripheral side of the focal length adjusting lens unit L202. The vibration actuator 205 is mounted on the frame 207.
Is in contact with the flat portion 207a provided on the outer peripheral surface of the flat portion 2 when the vibration actuator 205 is driven.
07a is applied with a driving force in the optical axis direction. As a result, the frame 2
07 and the focal length adjusting lens unit L202 are arranged in parallel with the optical axis, and the linear guide 20 penetrating through the frame body 207.
8 to move in the optical axis direction. As described above, in the lens barrel disclosed in Japanese Patent Application Laid-Open No. H8-21279, 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]

However, the above-mentioned conventional lens barrel has the following problems. First,
When the frame of the imaging optical system is driven directly in the optical axis direction using a linear vibration actuator, the positioning accuracy of the frame is determined by the minimum distance (hereinafter, referred to as a distance that the vibration actuator can move the frame). "Drive unit"). Therefore, there has been a problem that the accuracy of focusing adjustment or focal length adjustment cannot be improved beyond the driving unit of the linear vibration actuator. Also,
When the frame of the photographing optical system is driven by using the ring-shaped vibration actuator, a helicoid mechanism or the like is disposed between the vibration actuator and the frame of the photographing optical system. No problem. However, in the ring-shaped vibration actuator, high surface accuracy is required for the contact surfaces of both the stator and the rotor. This surface accuracy is not particularly problematic in a small vibration actuator, but in a vibration actuator used in a lens barrel, the stator and the rotor have a diameter as large as the diameter of the lens barrel. There was a problem that it was difficult to secure appropriate surface accuracy.

On the other hand, a linear vibration actuator is
A plurality of driving force extracting portions are formed in the abdomen of the bending vibration in a projecting shape, and the driving force extracting portions (hereinafter, sometimes referred to as projecting portions) have a width in the width direction. Therefore, when the driven member is a rotating body, the relative movement speed of the projection differs depending on the location. For this reason, sound or heat may be emitted from the sliding surface between the rotating body and the projection. For this reason, if the protrusion is simply reduced in size, the vibration actuator may fall down, and cannot stably make frictional contact with the rotating body. In addition, linear type vibration actuators are designed so that the dimensional ratio in the length direction and the thickness direction is almost constant in order to generate longitudinal vibration and bending vibration in harmony. In addition, the space efficiency was poor for those having a small inner / outer diameter ratio and being longer in the direction of the rotation axis.

A first object of the present invention is to provide a stable frictional contact without generating noise or heat on a sliding surface between a vibration actuator and a relative motion member, a small inner / outer diameter ratio, An object of the present invention is to provide a vibration actuator driving device that is space-efficient for a device that is long in the rotation axis direction. A second object of the present invention is to provide a lens barrel that drives a focus adjustment lens group or the like using a vibration actuator, in which positioning accuracy of the focus adjustment lens group or the like is high, and
An object of the present invention is to provide a lens barrel having a structure that does not require high surface accuracy.

[0010]

In order to solve the above-mentioned problems, a first aspect of the present invention is to provide a driving force by harmoniously generating a symmetric elongational vibration that expands and contracts in a predetermined plane and a non-axisymmetrical vibration. And a relative motion member that contacts the vibration actuator and performs relative motion including rotary motion at least in part with the vibration actuator, and a direction of a rotation axis in the rotary motion is: A vibration actuator driving device is provided that is substantially parallel to the predetermined plane and substantially perpendicular to a vibration direction of the non-axisymmetric vibration.

According to a second aspect of the present invention, in the vibration actuator driving device according to the first aspect, the vibration actuator includes a vibrator formed in a plate shape, and a vibrator and a relative movement member interposed between the vibrator and the relative motion member. Pressurizing mechanism for generating pressure, the vibrator is provided with an opening including the center of the vibrator in the predetermined surface, the pressurizing mechanism,
A vibration actuator driving device for applying the pressing force near an opening of the vibrator is provided.

According to a third aspect of the present invention, in the vibration actuator driving device according to the second aspect, the pressing mechanism comprises:
Provided is a vibration actuator driving device that contacts the vibrator at a thickness portion of the vibrator in the opening and applies the pressing force to the contact surface.

According to a fourth aspect of the present invention, in the vibration actuator driving device according to the second or third aspect,
A flat portion substantially parallel to the vibration direction of the non-axisymmetric vibration is formed in the opening, and the pressing mechanism contacts the vibrator at a thickness portion of the vibrator in the flat portion, Provided is a vibration actuator driving device that presses the vibrator in the direction of the relative motion member by applying the pressing force to a surface.

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, in a direction intersecting a plane including the vibration of the symmetric extension vibration of the vibrator. Provided is a vibration actuator drive device provided with a position regulating member for regulating movement of the actuator.

According to a sixth aspect of the present invention, there is provided a support for supporting at least a part of an optical system and movable in a direction of an optical axis of the optical system. The vibration actuator driving device described above, and a conversion unit that converts the rotational motion about the optical axis into a linear motion in the optical axis direction and transmits the linear motion to the support unit, and the vibration actuator driving device includes the relative motion. A member constitutes a rotating part rotatable around the optical axis, and the vibration actuator comprises:
By rotating the rotating part by frictionally contacting a part of the rotating part, or by being provided in the rotating part and frictionally contacting a part of another member facing the rotating part, A rotation unit drives the rotation unit, and the conversion unit provides a lens barrel that converts the rotation movement of the rotation unit into the linear movement in the optical axis direction.

According to a seventh aspect of the present invention, in the lens barrel according to the sixth aspect, the lens barrel further comprises a fixed cylinder for accommodating the vibration actuator, wherein the vibration actuator is accommodated within a thickness of the fixed cylinder. Provide a lens barrel.

[0017]

Embodiments of the present invention will be described below in more detail with reference to the drawings. In the following description, an example of an ultrasonic actuator using an ultrasonic vibration region will be described as the vibration actuator. In addition, portions that perform the same functions as those of the above-described conventional example are given the same reference numerals or the same reference numerals at the end, and redundant description will be omitted as appropriate.

(Embodiment of Vibration Actuator Driving Apparatus) FIG. 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 a vibration actuator according to the embodiment of FIG. FIG. 3 is a conceptual diagram showing a vibration mode of the vibration actuator according to the embodiment of FIG. The vibration actuator driving device of this embodiment includes a rotating body (relative motion member) 140 and an ultrasonic actuator 110.

The ultrasonic actuator 110 is shown in FIG.
As shown in (a), a vibrator 111 formed of a donut-shaped piezoelectric element, which is an electromechanical conversion element for converting electric energy into mechanical displacement, and a vibrator 111 formed on one surface of the vibrator 111 and having a center line CL It comprises two electrodes 112 and 113 in the shape of a half-donut plate symmetrically arranged with respect to each other, and a driving force extracting portion 114 and the like provided on the outer periphery of the vibrator 111 and intersecting the center line CL. I have.

The vibrator 111 has a (R, 1) mode (FIG. 3A), which is a symmetric elongation vibration in the radial direction (plane direction), and a non-axially symmetric in-plane bending vibration ((1,1)). )) The dimensional ratio is such that the mode [FIG. 3 (b)] occurs simultaneously.

As shown in FIG. 2B, a drive circuit 120 for driving the ultrasonic actuator 110 includes an oscillator 121 for outputting a drive signal of an AC voltage having a predetermined frequency,
A phase shifter 122 for converting the phase of the drive signal generated from the oscillator 121 by 90 °, an amplifier 123 for amplifying the drive signal from the oscillator 121 and connecting to the A terminal, and a phase shifter 12
And an amplifier 124 for amplifying the drive signal from the second terminal and connecting to the B terminal.

The ultrasonic actuator 110 is shown in FIG.
When signals having a phase difference of 90 degrees are input to the two electrodes 112 and 113 shown in FIG.
Vibrations having phases different by 0 degrees are generated, and an elliptical motion is generated in the driving force extracting unit 114. By bringing the rotating body 140, which is a relative movement member, into pressure contact with the driving force extracting section 114, it is possible to cause relative movement between the ultrasonic actuator 110 and the rotating body 140.

As shown in FIG. 3, the ultrasonic actuator 110 has an expansion / contraction surface of a symmetric elongation vibration generated in the vibrator 111 (an expansion / contraction direction in the driving force take-out portion 114 is indicated by an arrow A) and a rotation of the rotating body 140. Axial direction of axis O (see Fig. 1)
Are substantially parallel. In addition, non-axisymmetric vibration ((1,
The vibration direction (arrow B) of the 1)) mode is substantially orthogonal to the axial direction of the rotation axis O of the rotating body 140, and substantially coincides with the rotational tangent direction T of the rotating body 140 (see FIG. 1). . here,
When 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 causes an elliptical motion, and can rotate the rotating body 140. At this time, since the direction of the vibration in the ((1, 1)) mode substantially coincides with the circumferential direction (tangential direction) of the rotational motion, the force can be transmitted efficiently.

According to the present embodiment, the ultrasonic actuator 110 using the symmetric elongation vibration and the non-axisymmetric vibration is employed, and the axial direction of the rotation axis of the rotating body 140 is adjusted to the symmetric elongation vibration generated in the vibrator 111. The driving state is substantially parallel to the expansion and contraction surface and substantially perpendicular to the vibration direction of the non-axisymmetric vibration, so that it is possible to realize a driving state in which noise during driving is small and power transmission efficiency is good.

(First Embodiment of Lens Barrel) FIG. 4 is a view showing a first embodiment of a lens barrel using a vibration actuator driving device according to the present invention. In the lens barrel of FIG. 4, the ultrasonic actuator 110B is disposed in a housing 151 provided within the thickness t of the fixed barrel 150 of the lens barrel. At that time, the ultrasonic actuator 110B
The elastic surface of the symmetric elongation vibration generated in the vibrator 111 is substantially parallel to the axial direction of the rotation axis O of the rotating body 140B, and
Vibration direction of non-axisymmetric vibration and rotation axis O of rotating body 140B
Are arranged so that the axial direction is substantially perpendicular to the axis direction. The rotational force of the rotating body 140B is transmitted to a moving mechanism of a moving lens that moves for focusing, zooming, and the like.

According to this embodiment, for a lens barrel having a small inner / outer diameter ratio and a longer length in the direction of the rotation axis,
Space efficiency can be improved.

(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, and FIG. 6 is an enlarged view of the vibrator of FIG. FIGS. 7 and 8 are views showing a supporting and pressing mechanism of the vibration actuator driving device of FIG.

The lens barrel of the present embodiment is a fixed barrel 150C having an ultrasonic actuator 110C and a housing 151 for housing the ultrasonic actuator 110C.
And a support member 132 for supporting the ultrasonic actuator 110C, and a rotating body 14 rotatably supported around the optical axis.
0C, ultrasonic actuator 110C and rotating body 140
And a pressure member 133 for bringing C into pressure contact.

As shown in FIG. 6, the ultrasonic actuator 110C has a substantially circular outer shape, a vibrator 111C made of a piezoelectric element having an opening 115 formed in the center, and is formed on one plane of the vibrator 111C. And two electrodes 1 symmetrically arranged apart from each other with respect to the center line CL.
12, 113, and 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 so on. The opening 115 is connected to the vibrator 111.
It comprises a circular portion 115a formed substantially concentrically with C, and two notch portions 115b formed in a rectangular shape at two opposing locations on the circumference of the circular portion 115a.

The accommodating portion 151 is formed on the outer surface of the fixed cylinder 150C so as to have a substantially rectangular notch, and accommodates the ultrasonic actuator 110C within the thickness t of the fixed cylinder 150C. ing.

The support member 132 includes a support pin 132a (FIG. 7) attached to the ceiling 151a of the housing 151.
(See (b)), an L-shaped arm portion 132b provided at the tip of the support pin 132a, and an L-shaped arm portion 132b provided at the tip of the arm portion 132b and inserted into the opening 115 of the vibrator 111C. A pressing plate portion 132c (see FIG. 8A) that presses the flat portion of the notch portion 115b, and a pressing plate portion 132c that is detachable from the pressing plate portion 132c with a screw or the like and inserted into the opening 115. And a fixing portion 132e for fixing the member so as not to come off.

The arm 132b is provided so as to be movable in the axial direction of the support pin 132a. Press plate 132c
Is inserted into the opening 115 of the vibrator 111C as shown in FIG. 8B, and its lower surface (the area indicated by P in FIG. 8)
Presses the flat part of the notch 115b.

As shown in FIGS. 7 (a) and 8 (a), the pressing plate portion 132c and the fixing portion 132e respectively
Arms are formed in two directions from the center side of the vibrator 111C to the outer peripheral side along a direction parallel to the contact surface between the driving force extracting portion 114 and the rotating body 140. Then, the vibrator 111C is sandwiched between the ends of the arms, and the vibration is caused (B in FIG. 5).
A projection (position regulating member) 132d (FIG. 7A, FIG. 8) for preventing the -B line from rotating.
(See (a)). That is, the pressing plate 13
By interposing the vibrator 111C between the projection 132d on the 2c side and the projection 132d on the fixed part 132e,
The connection between the vibrator 111C and the support member 132 and the vibrator 1
11 is performed.

The pressing member 133 is composed of a coil spring inserted into the support pin 132a, and presses the upper plate 132b 'of the arm 132b downward, thereby causing the driving force extracting member 114 to rotate via the pressing member 132c. Press 140.
When the length of the coil spring is equal to the distance between the ceiling of the housing part 151 and the upper plate 132b 'of the arm part 132b, the coil spring presses the driving force extracting part 114 against the rotating body 140 with a predetermined pressure. It is set as follows.

When assembling the ultrasonic actuator 110C into the lens barrel, first, with the coil spring, which is the pressing member 133, attached, the support pin 13 of the support member 132 is mounted.
2a is the ceiling part 151a of the accommodation part 151 of the fixed cylinder 150C.
Fixed to. At this time, the fixing portion 132 of the support member 132
e is removed from the pressing plate 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 housing 151. Thereafter, the vibrator 111C of the ultrasonic actuator 110C is disposed in the housing 131 so that the pressing plate 132c is inserted into the opening 115 thereof. Finally, the support member 132
Is fixed to the pressing plate 132c with screws or the like.

According to the lens barrel of the present embodiment, the ultrasonic actuator 110C, the support portion 132, and the pressing member 1
33 can be accommodated in the thickness portion of the fixed cylinder 150C with good space efficiency. Further, since the support member 132 contacts and presses the vibrator 111C at the thickness portion (flat portion) of the notch 115b, stable pressurized support is possible.
Further, since the vibrator 111C is regulated from both sides, it is possible to stably support the vibrator 111C and to perform efficient vibration.

(Third Embodiment of Lens Barrel) FIG. 9 is a sectional view showing a third embodiment of the lens barrel according to the present invention. The frame 166 is a member that holds the focusing lens group L161. The frame 166 is connected to the fixed cylinder 161 by a helicoid 169. A rotating cylinder 162 is rotatably mounted in front of the fixed cylinder 161 on the optical axis. A key groove 162a is formed on the inner periphery of the rotary cylinder 162 in parallel with the optical axis. Further, the focusing lens group L
A key 166a is formed on one frame 166,
The key 166a is engaged with the key groove 162a.

A rotor 140D is integrally fixed to an end of the rotary cylinder 162 behind the optical axis. Rotor 140D
Has a flat portion 140D-1 perpendicular to the optical axis at the rear of the optical axis. Further, the rotor 140D has a circumferential groove 14 on the outer circumferential surface.
0D-2. The ball 141 is spread in the circumferential groove 140D-2. The sphere 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 retaining ring 164 is screwed into the inner peripheral side of the fixed cylinder 161. The holding ring 164 is a member that limits the movement of the ball 141 in the optical axis direction. By the action of the retaining ring 164,
The sphere 141 does not protrude from the lens barrel after the lens barrel is assembled. The holding ring 164 also limits the movement of the rotor 140D in the optical axis direction together with the ball 141.

The driving force extracting 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 pressing member 133 are the same as those shown in FIGS. 5 to 8, and the vibrator 111 is connected to the flat part 140D-1 of the rotor 140D. Press in the direction of.

The frame 167 is provided with a focal length adjusting lens unit L1.
62. The frame body 167 has through-holes 167a, 167b (167b) parallel to the optical axis direction in the thick part.
Is not shown because it overlaps with 167a).
Further, a flat portion 167c is formed on a part of the outer periphery.
The linear guide 168 is provided in the through hole 167a (167b).
Is inserted. The linear guide 168 is arranged parallel to the optical axis, and is fixed to the fixed cylinders 161 and 163.

A linear vibration actuator 165 is disposed at a position facing the flat portion 167c of the frame 167. The vibration actuator 165 mainly includes a vibrator 165a and a pressure member 165b.

As described above, in the present embodiment, a rotational driving force is applied to the rotor 140D by using the ultrasonic actuator 110D. Further, the rotational motion of the rotor 140D is converted into a linear motion in the optical axis direction by the helicoid 169, and then used for driving the focusing lens group L161. Therefore, in the present embodiment, the focusing lens group L
The positioning accuracy in the optical axis direction of the 161 is mainly based on the helicoid 1
69. In other words, in the present embodiment, regardless of the size of the driving unit of the ultrasonic actuator 110D, the positioning accuracy of the focusing lens group L161 is improved by appropriately determining the shape of the helicoid 169, and high-precision focusing adjustment is performed. It is possible to do.

Since the ultrasonic actuator 110D contacts only a part of the rotor 140D, the flat portion 140
D-1 has an advantage that a very strict flatness is not required. Generally, in the case of a vibration actuator such as an ultrasonic motor, the amplitude of vibration generated in the vibrator is on the order of microns, so that a flatness requirement is imposed on a moving member (rotor) that makes frictional contact with the vibrator and relatively moves. In addition, the requirement for flatness increases with the increase in the contact area between the vibrator and the moving element. Therefore, tentatively,
When a ring-shaped ultrasonic motor is used as in the lens barrel disclosed in JP-A-9-111117, the ultrasonic motor and the rotor are in contact with each other over the entire circumference of the rotor.
The flatness requirements for the rotor become very strict. On the other hand, in the present embodiment, a linear type ultrasonic actuator is employed and is brought into contact with only a part of the rotor 140D. It suffices to be guaranteed within a relatively small area corresponding to the thickness of 114. Therefore,
As described above, the flat portion 140D-1 of the rotor 140D.
The demand for flatness is relatively moderate, and its manufacture is easy.

(Modifications) Various modifications and changes are possible without being limited to the embodiment described above, and they are also within the scope of the present invention. For example, the driving force extracting unit 1
Although the example in which the protrusions are formed has been described, the friction material may be bonded. Also, the relative motion member is
It is not limited to an annular shape, and any shape having a trajectory including a rotational motion, such as a rotation within 360 ° and a motion that changes the curvature of a circle, may be used. In each embodiment of the lens barrel, an example was described in which one ultrasonic actuator was provided, but a plurality of, for example, three ultrasonic actuators may be provided.

[0045]

As described above, according to the invention described in each claim, the direction of the rotation axis in the rotational motion of the relative motion member is substantially parallel to the expansion and contraction surface of the symmetric elongation vibration generated in the vibrator. In addition, since the vibration direction of the non-axially symmetric vibration generated in the vibrator is substantially perpendicular to the vibration direction, the generation of noise during driving is reduced, and the power transmission efficiency 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. 1A is a front view and a plan view showing a configuration of a vibrator of a vibration actuator. FIG. 1 (b)
FIG. 3 is a block diagram illustrating a configuration of a drive circuit of the vibration actuator.

FIG. 3 is a schematic diagram illustrating a vibration mode of the vibration actuator according to the embodiment of FIG. 1; FIG. 3A shows a vibration mode of the (R, 1) mode which is a symmetric elongation vibration.
(B) is a figure which shows the vibration form of the ((1,1)) mode which is a non-axisymmetric vibration.

FIG. 4 is a schematic diagram showing a 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 along a plane parallel to the XZ plane, and FIG. 4B is a schematic diagram illustrating an arrangement state of a rotating body and a vibration actuator on an XY plane. FIG. 4C is a schematic diagram showing one cross section of a side surface taken along 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. 5A is a perspective view, and FIG.
It is the elements on larger scale of (b) part of (a).

FIG. 6 is an enlarged view of the vibrator of FIG. 5;

FIG. 7 is a schematic diagram showing a pressurized form of the vibration actuator driving device of FIG. FIG. 7 (a) is a diagram showing the A-
FIG. 7B is a diagram illustrating a cross section taken along a line BB in FIG. 5.

8 is a schematic diagram showing a configuration of a pressurizing mechanism of the vibration actuator driving device of FIG. FIG. 8A is a schematic perspective view showing a configuration of a contact portion with the vibrator. FIG. 8B
FIG. 8 is a cross-sectional view taken along the line CC in FIG. 7A, showing a configuration of a contact portion with a vibrator.

FIG. 9 is a schematic view 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 Electrode 114 Driving Force Extraction Section 132 Supporting Member 133 Pressing Member 140 Rotating Body (Relative Motion Member) 150 Fixed Cylinder

Claims (7)

[Claims] 1. A symmetrical stretching vibration that expands and contracts in a predetermined plane;
A vibration actuator that generates a driving force by harmoniously generating non-axisymmetric vibration; and a relative motion member that contacts the vibration actuator and performs relative motion including rotational motion at least in part with the vibration actuator. And a direction of a rotation axis in the rotational motion is substantially parallel to the predetermined plane and substantially orthogonal to a vibration direction of the non-axisymmetric vibration. 2. The vibration actuator driving device according to claim 1, wherein the vibration actuator is configured to generate a pressing force between the vibrator formed in a plate shape and the vibrator and the relative motion member. A pressure mechanism, wherein the vibrator is provided with an opening including the center of the vibrator on the predetermined surface, and the pressurizing mechanism acts on the pressing force near the opening of the vibrator. A vibration actuator driving device characterized in that the driving is performed. 3. The vibration actuator driving device according to claim 2, wherein the pressure mechanism contacts the vibrator at a thickness portion of the vibrator in the opening, and applies the pressing force to a contact surface thereof. A vibration actuator driving device characterized in that the driving is performed. 4. The vibration actuator driving device according to claim 2, wherein the opening is formed with a flat portion substantially parallel to a vibration direction of the non-axisymmetric vibration, Vibrating the vibrator, wherein the vibrator contacts the vibrator at a thickness portion of the vibrator in the plane portion and applies the pressing force to the contact surface to press the vibrator in the direction of the relative motion member. Actuator drive. 5. The method according to claim 1, wherein:
The vibration actuator driving device described in the paragraph, further comprising: a position regulating member that regulates movement of the vibrator in a direction intersecting a plane including the vibration of the symmetric elongation vibration. 6. A vibration actuator according to claim 1, which supports at least a part of an optical system and is movable in a direction of an optical axis of said optical system. A driving unit, and a conversion unit that converts the rotational motion about the optical axis into a linear motion in the optical axis direction and transmits the linear motion to the support unit, wherein the vibration actuator driving device is configured such that the relative motion member is the optical axis. Constituting a rotating portion rotatable around, wherein the vibration actuator drives the rotating portion to rotate by frictionally contacting a part of the rotating portion, or provided in the rotating portion, the rotating portion The frictional contact with a part of another member opposed to the rotating unit drives the rotating unit to rotate, and the converting unit converts the rotating motion of the rotating unit into the linear motion in the optical axis direction. Lens barrel. 7. The lens barrel according to claim 6, further comprising a fixed cylinder that houses the vibration actuator, wherein the vibration actuator is housed within a thickness of the fixed cylinder. Lens barrel.