JP2016136836A - Ultrasonic motor and lens device having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in which the degree of design freedom of an ultrasonic motor is restricted since there is a need to set a node of vibration in the vicinity of the center of a contact surface of a driven part pressed by a vibrator for excellent pressure contact, without inhibition of ultrasonic vibration of the vibrator.SOLUTION: An ultrasonic motor comprises: a vibrator which has a contact surface brought into contact with a driven part, includes a piezoelectric element, and drives the driven part with ultrasonic vibration excited by the piezoelectric element; a holding part which holds the vibrator; pressure means which applies an energization force for energizing the holding part toward the driven part in order to press the contact surface against the driven part; and a fixing part which supports the pressure means. The holding part holds the vibrator on both sides of the contact surface in the drive direction of the driven part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an ultrasonic motor that drives a driven part by generating an elliptical vibration in a pressed vibrator, and a lens device using the ultrasonic motor.

  Conventionally, for example, an ultrasonic motor has been adopted as a drive source for a camera or a lens, taking advantage of features such as silent operation, driving from low speed to high speed, and high torque output. The ultrasonic motor disclosed in Patent Document 1 includes an annular driven part having a rotation shaft and a plurality of vibrators, and the vibrators are in contact with the driven part in a pressed state. It is in a so-called pressure contact state, and is arranged on the annular driven part at a predetermined interval. When ultrasonic vibration is excited in the vibrator under the pressure contact state, an elliptical motion occurs in a portion of the vibrator that is in contact with the driven part, and the driven part is centered on the rotation axis of the driven part. Driven by rotation. The pressing contact state of the vibrator to the driven part can be obtained by urging a portion corresponding to a vibration node set near the center of the vibrator with a leaf spring. The pressing force is adjusted by a screw and an adjustment washer provided near the fixed portion of the leaf spring.

JP 2006-158052 A Japanese Patent Laid-Open No. 2004-304877

  However, in the ultrasonic motor disclosed in Patent Document 1, in order to prevent the ultrasonic vibration excited by the vibrator from being obstructed, a vibration node must be set at a position pressed by the vibrator. There wasn't. In addition, in order to obtain a good pressure contact state between the contact surface of the vibrator and the driven part, it is necessary to press at the center of the contact surface. There is a problem that the degree of freedom of design for vibration is limited.

  The present invention has been made to solve the above-described problems, and in an ultrasonic motor that drives a driven part by ultrasonic vibration generated in the vibrator, the contact surface between the vibrator and the driven part is excellent. An object of the present invention is to provide an ultrasonic motor with improved design freedom with respect to vibration while ensuring a pressurized contact state.

In order to solve the above problems, the ultrasonic motor of the present invention has the following configuration.
The ultrasonic motor has a contact surface that comes into contact with the driven part and includes a piezoelectric element, the vibrator that drives the driven part by ultrasonic vibration excited by the piezoelectric element, and A holding unit that holds a vibrator; a pressing unit that applies a biasing force that biases the contact surface toward the driven unit; and a fixing that supports the pressing unit. The holding portion holds the vibrator on both sides of the contact surface in the driving direction of the driven portion, and the vibrator forms a contact surface with the driven portion. A flat plate portion including the piezoelectric element, a bonding portion that is bonded to the holding portion to hold the vibrator, and a connection portion that connects the bonding portion and the flat plate portion, The connection part has a higher vibration damping rate than the flat plate part. To.

  According to the present invention, in an ultrasonic motor that drives a driven part by ultrasonic vibration generated in the vibrator, a design for vibration is ensured while ensuring a good pressure contact state between the contact surface of the vibrator and the driven part. An ultrasonic motor having an improved degree of freedom can be provided.

It is a disassembled perspective view of the ultrasonic motor in Example 1 of the present invention. It is a perspective view in the state where each member shown in Drawing 1 was built. It is an expansion perspective view which shows the joining state of a vibrator | oscillator and a small base. (A) And (B) is an expanded sectional view showing the state where each member in Example 1 was incorporated. (C) is an enlarged detail view of part A of (B), showing a component vector of the pressing force of the elastic member. It is an expanded sectional view which shows the state which the rotor and the ring base each inclined. (A) And (B) is an expanded sectional view showing the state where each member in Example 2 was incorporated.

[Example 1]
Embodiments of the present invention will be described below with reference to the drawings. The ultrasonic motor of the present embodiment will be described by taking a rotary drive motor unitized as a drive actuator such as a lens barrel for a digital camera as an example, but the usage is not limited to this.

  FIG. 1 is an exploded perspective view of an ultrasonic motor according to an embodiment of the present invention. In the drawings, the same members are indicated by the same symbols. Reference numeral 101 denotes a rotor which is a driven part, which includes a contact surface 101a with which a vibrator 109 described later comes into pressure contact with a pressing force. Reference numeral 102 denotes a vibration plate that comes into contact with the contact surface 101a in a pressure contact state with pressing. An elliptical motion can be generated by applying a voltage to the piezoelectric element 103 in a state where the piezoelectric element 103 is pressure-bonded to the diaphragm 102. The vibration plate 102 and the piezoelectric element 103 constitute a vibrator 109. In this embodiment, the rotor 101 is rotationally driven by three vibrators 109. Reference numeral 104 denotes a small base as a holding unit for holding the vibrator 109. Reference numeral 105 denotes a ring base as a fixing portion, which holds a small base 104, a pressure member 106 and a leaf spring 107, which will be described later. Reference numeral 106 denotes a pressure member that fits into the through hole 105b of the ring base 105, is held so as to be movable only in a direction perpendicular to the contact surface 101a of the rotor 101, and is pressed from a plate spring 107 described later. The vibrator 109 is brought into pressure contact with the rotor 101 via the small base 104 by pressure. Reference numeral 107 denotes a leaf spring which is an elastic member. Both ends of the leaf spring are fixed to the ring base 105 with screws 108, and the vibrator and the driven portion are brought into pressure contact with the pressing force of the leaf spring. The pressing member 106 and the leaf spring 107 serve as the pressing unit of the present invention.

  As described above, each member described above is incorporated and unitized as an ultrasonic motor.

  FIG. 2 is a perspective view showing a state in which each member of FIG. 1 is incorporated. In FIG. 2, the configuration around the vibrator 109 is the same in all three locations, and numbers are given only to the front side in the drawing in order to prevent complexity of the drawing. As shown in the figure, the pressing force is applied to the vibrator 109 via the pressure member 106 and the small base 104 by the leaf springs 107 fixed by two screws 108 at three locations on the ring base 105. As a result, the contact surface 101a of the vibrator 109 and the rotor 101 comes into pressure contact. When incorporated in an actual lens barrel or the like, the rotor 101 is driven by being connected to a focus mechanism or a zoom mechanism.

  Next, details of components of the ultrasonic motor will be described. FIG. 3 is an enlarged perspective view for explaining the connection state of the diaphragm 102 and the small base 104 in FIGS. 1 and 2 and is a view seen from the rotor 101 side. In the figure, two projections 102b are formed on the flat plate 102a at the center of the diaphragm 102. The upper end surface of the protrusion, that is, the surface that contacts the contact surface 101a of the rotor 101 is formed in the same plane and is finished to a uniform surface by polishing or the like during the manufacturing process in order to improve the contact state with the contact surface. It is done.

  On the other hand, the piezoelectric element 103 is pressure-bonded with an adhesive or the like on the back surface side of the flat plate portion 102a shown in FIG. 3 (the surface side opposite to the surface on which the two protruding portions 102b are formed). Note that the method of press-bonding the back side of the flat plate portion 102a and the piezoelectric element 103 is not limited as long as the press-bonding is performed. The piezoelectric element 103 is formed by laminating and integrating a plurality of piezoelectric element films. The laminated piezoelectric element 103 is excited by applying a desired AC voltage, and two vibration modes are excited on the diaphragm 102 to which the piezoelectric element 103 is pressure-bonded. At this time, by setting the vibration phases of the two vibration modes to be a desired phase difference, an elliptical motion as indicated by an arrow in FIG. 3 occurs in the protrusion 102b. This elliptical motion is generated by three vibrators 109 as shown in FIGS. 1 and 2 and transmitted to the contact surface 101a of the rotor 101, whereby the rotor 101 can be driven to rotate. Note that details regarding the laminated structure and vibration mode of the piezoelectric element described above are the same as the contents described in Patent Document 2, and a description thereof will be omitted.

  Next, two joint portions 102 c are formed at both ends of the diaphragm 102 to join the upper surface portion 104 a formed on both sides of the small base 104. The diaphragm 102 is joined to the small base 104 by welding or adhesion at the joint 102c. However, as long as the diaphragm 102 and the small base 104 are joined, the method is not limited. Two arm portions (connection portions) 102d are formed between the two joint portions 102c and the flat plate portion 102a, and the diaphragm 102 and the piezoelectric element 103 are connected to the small base via the arm portions 102d. 104 is fixed. The arm portion 102d is difficult to transmit the vibration generated in the flat plate portion 102a to the joint portion 102c, that is, has a high vibration damping rate. Therefore, as shown in FIG. It has a thin shape. In other words, a connection configuration in which the small base 104 that is a rigid body does not hinder vibration generated in the flat plate portion 102a is realized by the joint portion 102c. In addition, a predetermined gap 203 is formed between the flat surface portion 104 b near the center of the small base 104 and a surface (not shown) facing the flat surface portion 104 b of the piezoelectric element 103.

  In an ultrasonic motor driven by the frictional force between the contact surfaces of the vibrator 109 and the rotor 101, it is important to press at the center of the flat plate portion 102a to reduce the pressing unevenness in order to ensure a good contact state. In order to press the center of the flat plate portion 102a, it is necessary to press the center of the vibrator 109. In the ultrasonic motor disclosed in Patent Document 1, the vibrator is directly pressed. Therefore, in order not to inhibit the ultrasonic vibration excited by the vibrator 109, it is necessary to set the center of the vibrator 109 as a vibration node. Therefore, when combining the two vibration modes to cause the protrusion 102b to generate an elliptical motion, it is necessary to set a vibration node at the center of the vibrator 109 for both vibration modes. For this reason, there is a problem that the degree of freedom in design of vibration is limited.

  However, in the ultrasonic motor of the present invention, since the vibrator 109 is held by the holding member 104 via the arm portion 102d that suppresses the propagation of vibration, there is no need to set a vibration node at the center of the vibrator 109. . Therefore, for example, as described in Patent Document 2, it is possible to set a vibration mode in which a node of one vibration mode does not exist at the center of the vibrator 109 among the two vibration modes. As a result, an ultrasonic motor having a high degree of freedom in vibration design can be realized.

  In the ultrasonic motor of the present invention, the arm portion 102d is provided on the outer side in the driving direction with respect to the protruding portion 102b. Further, a joint portion 102c is provided on the outer side in the driving direction with respect to the arm portion 102d. Thereby, the magnitude | size of the direction orthogonal to a drive direction, ie, the radial direction of a rotor, can be suppressed. Therefore, the miniaturization of the ultrasonic motor can be realized by the present invention.

  FIGS. 4A and 4B are enlarged cross-sectional views showing a state in which each member is incorporated, and only the periphery of one of the three vibrators 109 in FIG. 2 is enlarged. The remaining two locations have the same configuration and will not be described.

  FIG. 4A is a view with the rotor 101 on the upper side, and in each of the two protrusions 102b of the diaphragm 102, the center of gravity of each upper end surface that is a surface in contact with the contact surface 101a of the rotor 101, A plane including the normal line of each upper end surface starting from each center of gravity is defined as a cut surface.

  4B is a surface that includes the center of gravity of the entire upper end surface that contacts the contact surface 101a and the normal line of the contact surface 101a, and is orthogonal to FIG. 4A, in the protrusion 102b of the diaphragm 102 in FIG. Is the cut surface. However, the entire upper end surface includes all the two upper end surfaces.

  4A and 4B, 201 is a center line that passes through the center of gravity of the entire upper end surface in contact with the contact surface 101a and includes the normal line of the contact surface 101a in the protrusion 102b of the diaphragm 102. .

  The upper end surface of the protrusion 102b is in contact with the contact surface 101a of the rotor 101 and is in a pressure contact state. Further, the diaphragm 102 is joined to the small base 104 at two upper surface portions 104a at the joint portions 102c at both ends. A predetermined gap 203 is formed between the piezoelectric element 103 and the flat portion 104 b of the small base 104.

  A hole 104c and an elongated hole 104d are provided on the lower surface side of the small base 104, and two shaft portions 105a formed on the ring base 105 are fitted. A contact portion 104 e is provided at the lower center of the small base 104. The contact portion 104e has a semi-cylindrical shape in which an arc shape as shown in FIG. 4A extends in the depth direction of the paper (the left-right direction in FIG. 4B). The contact portion 104e is in contact with the upper end surface 106a of the pressure member 106. Since the upper end surface 106a is formed as a flat surface, the contact with the contact portion 104e is a line contact having a length in the depth direction of the paper surface in FIG. 4A (the left-right direction in FIG. 4B). It has become. In this embodiment, the abutting portion 104e has a semi-cylindrical shape having an arc shape as described above. However, if the abutting portion 104e and the upper end surface 106a of the pressure member 106 can maintain a linear line contact, the shape is sufficient Is not limited.

  The ring base 105 has a through hole 105b on the surface facing the plate spring as shown in FIG. 1, and the pressure member 106 is fitted into the through hole 105b to come into contact with the plate spring. Thus, it can cooperate with the leaf spring 107. Note that the central axes of the through-hole portion 105b and the pressure member 106 substantially coincide with the center line 201, that is, the axial direction perpendicular to the contact surface 101a. 4A and 4B, the leaf spring 107 is deformed on the lower spherical surface portion 106b of the pressure member 106, and the pressure member 106 is attached in the direction of the small base 104 by its elastic force. Touching in a state of force.

  The leaf spring 107 needs to have a small spring constant to some extent in order to reduce variations in the pressing force due to changes in the deformation amount. Therefore, the leaf spring should be as thin as possible and the length should be as long as possible. The plate spring 107 of the present embodiment uses a thin plate, and is formed in an arc shape in order to make the length as long as possible in an annular ultrasonic motor. By doing so, even if a slight change occurs in the amount of displacement of the pressing member 106 in the pressing direction, variation in the urging force due to the leaf spring can be suppressed to a small value. Accordingly, a mechanism for adjusting the pressing force with respect to the pressing force as in the conventional example becomes unnecessary. With the configuration described above, the vibrator 109 is pressed against the rotor 101 by the leaf spring 107 via the small base 104 and the pressure member 106.

  Next, with reference to FIGS. 4A, 4 </ b> B, and 4 </ b> C, a structure for transmitting a pressing force by the leaf spring 107 will be described. In the following description, the pressing force vector is a force vector including the direction and magnitude of the pressing force in the cross section of each figure.

  First, in FIG. 4A, the small base 104 is in contact with the pressure member 106 at the contact portion 104e. The small base 104 is in contact with the rotor 101 at two protrusions 102b, and the center of gravity of each contact surface is the same distance from the center line 201 in the driving direction of the rotor. On the other hand, regarding the contact between the leaf spring 107 and the pressure member 106, in this embodiment, the leaf spring is formed in an arc shape, so that the support portions at both ends of the leaf spring 107 and the input points of the pressing force (the leaf spring 107 and The contact point of the pressure member 106 does not exist on a straight line. Therefore, the cross section of the leaf spring when generating the pressing force is in a state having an inclination as shown in FIG. As a result, the vector of the pressing force input to the pressing member 106 by the leaf spring 107 can be illustrated as an arrow 206a. The contact point between the pressing member 106 and the leaf spring 107 does not exist on the center line 201 and shifts to a point 205 on the right side of the center line 201 in FIG.

  FIG. 4C shows an enlarged detailed view around the point 205 in the portion A of FIG. 4B. The pressing force applied to the pressing member 106 by the leaf spring 107 is represented by a vector 206 a and is inclined with respect to the center line 201. Therefore, the pressing force vector 206 a can be decomposed into a component vector 206 b in a direction parallel to the center line 201 and a component vector 206 c in a direction perpendicular to the center line 201.

  As shown in FIGS. 4A and 4B, the pressure member 106 is held on the ring base 105 with a degree of freedom only in a direction substantially parallel to the center line 201, so that the leaf spring 107 The pressing force vector 206a that presses the pressing member 106 is transmitted to the small base 104 with a force (vector 204a) corresponding to the component vector 206b in the direction of the center line 201.

  On the other hand, the pressing force (vector 204a) transmitted to the small base 104 is transmitted to the contact surface 101a by the two protrusions 102b, and the force with which each protrusion 102b presses the contact surface is half of the pressing force vector 204a. The pressing force of the magnitude (vector 204b). Therefore, it is possible to keep the pressing force at the two protruding portions 102b uniform.

  In addition, since the contact between the protrusion 102b and the contact surface 101a is a surface contact, in reality, a pressing force uniformly distributed in the surface is presented. However, in order to facilitate understanding, it acts on the center of gravity position in the surface. Expressed as a force vector. Further, since the contact between the pressing member 106 and the contact portion 104e of the small base 104 is a line contact, in reality, the pressure vector is uniformly distributed on the straight line. It is expressed as a vector of the force that works on. Hereinafter, surface contact and line contact are also expressed by a force vector at the center of gravity.

  Further, a frictional force generated by a component vector 206c in a direction perpendicular to the center line 201 of the pressing force vector 206a input to the pressing member 106 is generated by the leaf spring 107 on the side surface of the pressing member 106. On the other hand, a frictional force is also generated in the fitting at the shaft portion 105a. Since these frictional forces are sufficiently small with respect to the pressing force, they are ignored. In fact, if the finish on this side surface is smoothed to some extent, the influence of the frictional force can be reduced to a negligible level.

  In this embodiment, as described above, the pressure member 106 is generally held with respect to the ring base 105 in a state having a degree of freedom only in the direction of the center line 201. Therefore, the pressing force vector 204 a applied to the small base 104 by the pressing member 106 can be made to substantially coincide with the center line 201. At this time, the magnitude of the pressing force vector 204a is equal to the component vector 206b in a direction parallel to the center line 201 of the pressing force vector 206a by the leaf spring. This is because only the component vector 206b of the pressing force vector 206a becomes the pressing force vector 204a. The component vector 206c in the direction perpendicular to the center line 201 of the pressing force vector 206a affects the frictional force on the side surface of the pressing member 106. Note that the side surface of the pressure member 106 and the inner surface of the through-hole portion 105b are finished smoothly, so that the generated friction force is sufficiently smaller than the pressing force, and the smooth advance and retreat of the pressure member 106 is not hindered. Finally, the pressing force vector applied to the contact surface 101a by one protrusion 102b is 204b, and the magnitude thereof is half of the pressing force vector 204a. This is because there are two protrusions 102b as shown in FIG. As described above, referring to the cross-sectional views of FIGS. 4A and 4B, the force point of the input pressing force vector 206 a is deviated from the center line 201, and the direction is not parallel to the center line 201. However, the pressing force vectors 204a and 204b can maintain a good pressing force.

  On the other hand, the small base 104 is configured to be pressed through a linear contact portion of the contact portion 104e. Therefore, in the cross section in FIG. 4 (A), the small base 104 can be tilted, and even if a dimensional error during production or a tilt of the member due to disturbance occurs, a good pressure contact state is obtained. Can keep.

  FIG. 5 is a cross-sectional view of the same member shown in FIG. 4 (A) in the same cross section. Compared with the state of FIG. 4 (A), the rotor 101 and the ring base 105 are brought into contact with the small base 104. A case where a relative inclination occurs with the contact portion 104e as the rotation center is shown. Also in FIG. 5, the protrusion 102 b of the diaphragm 102 follows the contact surface 101 a of the rotor 101 and maintains a good pressure contact state. The small base 104 and the ring base 105 are fitted in the hole 104c, the long hole 104d, and the shaft 105d, but may be inclined because a fitting play, that is, a fitting gap is provided. it can. Therefore, even if the rotor 101 or the ring base 105 is tilted due to a dimensional error during manufacturing, or is tilted due to vibration or disturbance during driving, the contact surface 101b at the two protruding portions 102b is moved to. Can be pressed well.

  That is, in the cross section of FIG. 4A, even when the inclination shown in FIG. 5 occurs between the members, the contact portion 104e of the small base 104 and the pressure member 106 in FIG. The contact is made as a single point contact, and the problem is solved by maintaining the followability between the contact surfaces with respect to the inclination. On the other hand, in the cross section shown in FIG. 4B, the contact between the contact portion 104e of the small base 104 and the pressure member 106 is a straight line contact, so that the small base in the left-right direction in FIG. The configuration is such that 104 and the pressure member do not tilt each other.

  As described above, in this embodiment, the vibrator 109 is held on the small base 104 via the arm portion 102d that suppresses the propagation of vibration. Accordingly, since there is no restriction on the position of the vibration node, it is possible to realize an ultrasonic motor with improved design freedom for vibration while ensuring a good pressure contact state between the contact surface of the vibrator and the driven part. Is possible.

[Example 2]
The second embodiment is a modification of the first embodiment, and is an example in which the contact portion where the small base 104 contacts the pressure member 106 has a spherical shape. 6A and 6B are enlarged cross-sectional views showing a state in which each member is incorporated, and only one of the three vibrators 109 is enlarged. The direction shown in the figure and the position of the cut surface are the same as those in FIGS. 4A and 4B. With reference to FIGS. 6A and 6B, the pressure member 106 is provided in the depth direction of FIG. 6A (FIG. 6B) by providing the small base 104 with a contact portion 104f having a spherical shape. In B), point contact is also made in the left-right direction), and tilting is possible. Accordingly, when the rotor 101 or the ring base 105 is tilted in the radial direction due to a dimensional error at the time of manufacturing, or due to vibration or disturbance during driving, the member is subjected to the depth direction in FIG. Even in the case where an inclination occurs in the left-right direction, it is possible to maintain good pressure contact at the two protruding portions 102b. In the present embodiment, the contact portion 104e has a spherical shape as described above, but the shape is limited as long as the contact portion 104f and the upper end surface 106a of the pressure member 106 can maintain point contact by one point. Not.

  The constituent elements other than the above-described hemispherical contact portion 104f and the method for transmitting the pressing force from the leaf spring 107 are the same as those in the first embodiment, and thus the description thereof is omitted here.

  As described above, in the second embodiment, since the small base 104 and the pressure member 106 are configured to be in point contact with the spherical contact portion 104f, not only the rotor drive direction but also the rotor drive direction is perpendicular. Even if there is a tilt in the direction, it is possible to maintain a good pressure contact state.

[Example 3]
By configuring the lens apparatus having the ultrasonic motor according to the first or second embodiment as a driving unit for driving a focus lens, a zoom lens, or the like, it is possible to realize a lens apparatus that can enjoy the effects of the present invention. it can.

  As described above, in the ultrasonic motor that drives the driven part by the elliptical vibration generated in the vibrator, the design freedom with respect to the vibration is ensured while ensuring a good pressure contact state of the contact surface between the vibrator and the driven part. By improving the above, it is possible to obtain a good pressure contact state on the contact surface without setting a vibration node near the center of the contact surface pressed by the vibrator as in the prior art.

  As mentioned above, although the preferable Example of this invention was described, this invention is not limited to these Examples, A various deformation | transformation and change are possible within the range of the summary.

101 Rotor (driven part)
101a Contact surface 102 Diaphragm 102a Flat plate part 102b Projection part 102c Joint part 102d Arm part (connection part)
103 Piezoelectric element 104 Small base (holding part)
105 ring base 106 pressure member 107 leaf spring (elastic member)
109 vibrator

In order to solve the above problems, the motor of the present invention has the following configuration.
A vibrator including a piezoelectric element, the vibrator driven by the vibration excited by the piezoelectric element;
A holding unit for holding the vibrator;
Pressurizing means for applying a biasing force that biases the holding portion toward the member in order to press the vibrator against the member;
With
The vibrator is
A flat plate portion having a protruding portion that comes into contact with the member by the biasing force;
A joining portion that joins the holding portion that holds the vibrator;
A connecting portion for connecting the joining portion and the flat plate portion;
With
The connecting portion is thinner than the flat plate portion and has a higher vibration damping rate than the flat plate portion.

Claims (7)

Ultrasonic motor
A vibrator having a contact surface in contact with the driven part and including a piezoelectric element, wherein the vibrator drives the driven part by ultrasonic vibration excited by the piezoelectric element;
A holding unit for holding the vibrator;
Pressurizing means for applying an urging force for urging the holding portion toward the driven portion in order to press the contact surface against the driven portion;
A fixing portion for supporting the pressurizing means;
With
The holding unit holds the vibrator on both sides of the contact surface in the driving direction of the driven unit;
An ultrasonic motor characterized by that. The vibrator is
A flat plate portion having a protrusion that forms the contact surface with the driven portion and including the piezoelectric element;
A joining portion joined to the holding portion to hold the vibrator;
A connecting portion for connecting the joining portion and the flat plate portion;
With
The connection portion has a high vibration damping rate with respect to the flat plate portion,
The ultrasonic motor according to claim 1.   The ultrasonic motor according to claim 2, wherein the connection portion is thinner than the flat plate portion. The pressurizing means includes a pressurizing member and an elastic member, and the elastic member applies a biasing force to the holding portion via the pressurizing member,
The holding portion includes a contact portion that is in point contact with the pressure member and includes a normal line that includes the contact surface and includes a normal line that passes through the center of gravity of the contact surface.
The ultrasonic motor according to claim 1, wherein the ultrasonic motor is provided. The pressurizing means includes a pressurizing member and an elastic member, and the elastic member applies a biasing force to the holding portion via the pressurizing member,
The holding portion includes a contact portion that is in line contact with the pressure member in a direction perpendicular to the driving direction of the driven portion.
The ultrasonic motor according to claim 1, wherein the ultrasonic motor is provided.   The ultrasonic motor according to claim 2, wherein a gap is provided between the vibrator and the holding portion.   A lens apparatus comprising the ultrasonic motor according to claim 1 as driving means for driving a driven part.

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