JP6011330B2 - Driving device and lens barrel - Google Patents

Description

  The present invention relates to a driving device and a lens barrel.

  There is known an imaging apparatus that performs processing such as autofocus by driving an optical system by a vibration wave motor (Patent Document 1).

JP 2009-153286 A

  When switching the driving direction of the optical system by the vibration wave motor, there is a problem that abnormal noise occurs. In the invention of Patent Document 1, when switching the driving direction, voltage application to the vibration wave motor is stopped to temporarily stop driving the optical system. At this time, when a voltage is applied to the vibration wave motor for driving after the direction is switched, an abnormal noise is generated with an increase in energy in the driving circuit. These abnormal sounds are recorded, for example, when a moving image is shot by the imaging apparatus.

  A driving apparatus according to the present invention generates a driving force by a signal generating unit that generates a pair of driving signals, an electromechanical transducer to which the driving signal generated by the signal generator is applied, and vibration of the electromechanical transducer. A vibrating body, a moving body that is pressed against the vibrating body and driven by a driving force, and a control unit that sets a frequency and a phase difference of a driving signal are provided. The control unit changes a driving direction of the moving body. In this case, the phase difference is changed after setting the frequency to a holding frequency at which the driving speed of the moving body is substantially zero.

  According to the present invention, it is possible to suppress the generation of abnormal noise when driving the vibration wave motor.

1 is a schematic view of a lens barrel according to an embodiment of the present invention. It is the schematic of the vibrating body of a vibration wave motor. It is a figure which shows the phase difference-rotational speed characteristic of a vibration wave motor. It is a figure which shows the frequency-rotation speed characteristic of a vibration wave motor. It is a block diagram of the drive device by one embodiment of the present invention. It is a flowchart regarding the drive control of the vibration wave motor by the drive device by one embodiment of this invention. It is an example of a timing chart regarding drive control of a vibration wave motor by a drive unit by one embodiment of the present invention. It is a figure for demonstrating a holding frequency. It is a flowchart regarding the setting process of holding frequency.

  FIG. 1 is a schematic view of a lens barrel according to an embodiment of the present invention. A lens barrel 2 in FIG. 1 is a lens barrel for an imaging apparatus such as a digital camera. The vibration wave motor 1 includes a vibrating body 161, a moving body 162, a buffer support member 163 made of a nonwoven fabric or the like, and a pressure contact means 164. The vibration wave motor 1 provides the lens barrel 2 with a driving force for driving the lens group L in the optical axis direction.

  The vibrating body 161 includes an elastic body 161a and a piezoelectric body 161b. The elastic body 161a is formed of a metal material having a high resonance sharpness. The shape of the elastic body 161a is an annular shape as shown in FIG. A piezoelectric body 161b is bonded to one circular surface of the elastic body 161a, and a comb tooth portion 121 having a groove is provided on the opposite surface.

  The piezoelectric body 161b is an electromechanical conversion element that converts electrical energy into mechanical energy. The piezoelectric body 161b is divided into two phases (A phase and B phase) along the circumferential direction. In each phase of the piezoelectric body 161b, the polarization is alternately arranged every ½ wavelength. Between the A phase and the B phase of the piezoelectric body 161b, a quarter wavelength interval is provided. A drive signal is output from the drive circuit 80 to each phase of the piezoelectric body 161b. The phase difference between the drive signal output to the A phase and the drive signal output to the B phase of the piezoelectric body 161b is variable. When a high frequency voltage is applied to the A phase and the B phase of the piezoelectric body 161b, the piezoelectric body 161b is excited. The deflection of the base portion 122 of the elastic body 161a due to the excitation of the piezoelectric body 161b is enlarged by the comb tooth portion 121 of the elastic body 161a and becomes a traveling wave on the driving surface 123 at the tip of the comb tooth portion 121. In the present embodiment, it is assumed that the piezoelectric body 161b has an electrode pattern in which nine traveling waves (9th order bending vibration waves) are likely to be generated.

  The moving body 162 is formed of a light metal such as aluminum. The moving body 162 is in pressure contact with the drive surface 123 by the pressure applied by the pressure contact means 164 having a pressure plate and a pressure member. An elliptical motion is generated at the wave front of the traveling wave generated in the driving unit 123. The moving body 162 brought into pressure contact with the drive surface 123 is driven by the friction due to the elliptical motion and rotates. The rotation direction of the moving body 162 changes depending on the phase difference between the A phase and B phase drive signals of the piezoelectric body 161b.

  The moving body 162 is provided with a vibration absorbing member 166 such as rubber that absorbs vibration in the optical axis direction of the moving body 162. The vibration absorbing member 166 is in pressure contact with the output transmission unit 155 by the pressure contact means 164. The rotational movement of the moving body 162 is transmitted to the output transmission unit 155. However, the output transmission unit 155 is restricted from moving in the optical axis direction and in the radial direction by a bearing 156 attached to the fixing member 151.

  The output transmission unit 155 has a protrusion 155a. The protrusion 155a is fitted with the fork 154. The fork 154 is transmitted with the rotational movement of the output transmission portion 155 via the protrusion 155a. Further, the rotational motion is transmitted to the cam ring 153. Inside the cam ring 153, a key groove 153a is cut spirally in the circumferential direction. A fixing pin 152a of the AF ring 152 is inserted into the key groove 153a. When the cam ring 153 rotates, the fixing pin 152a is guided and moved by the key groove 153a, and the AF ring 152 holding the lens group L moves in the optical axis direction.

  As described above, the traveling wave generated by the vibration wave motor 1 is transmitted to the AF ring 152 via the moving body 162, the output transmission unit 155, the fork 154, and the cam ring 153, and the lens group L is moved together with the AF ring 152. Driven in the optical axis direction. Using this drive, the lens barrel 2 performs a wobbling operation or the like.

  FIG. 3 is a diagram showing the relationship between the phase difference between the A phase and B phase drive signals and the rotational speed of the moving body 162. When the phase difference is + 90 °, the rotational speed of the moving body 162 is the maximum speed for forward rotation (for example, clockwise), and when the phase difference is −90 °, the rotational speed is the maximum speed for reverse rotation (for example, counterclockwise). Become.

  FIG. 4 is a diagram illustrating the relationship between the frequency of the drive signal and the rotational speed of the moving body 162. The rotational speed of the moving body 162 is substantially zero when the frequency of the drive signal is within a predetermined range. Here, “substantially zero” refers to a state in which a torque sufficient to rotate the movable body 162 in pressure contact with the vibration absorbing member 166 or the like is not generated. For example, within the range shown in FIG. 4, the rotational speed of the moving body 162 is zero within the range of 28.5 kHz to 30.0 kHz. Further, even if the frequency is lower than 28.5 kHz or higher than 30.0 kHz, torque sufficient to rotate the moving body 162 in pressure contact with the vibration absorbing member 166 or the like is not generated, and the cam ring 153 or the like rotates. However, there is a frequency at which the rotational speed of the moving body 162 is substantially zero. A frequency at which the rotational speed of the moving body 162 is substantially zero is referred to as a holding frequency f0.

  In the present invention, when switching the rotational drive direction of the moving body 162, voltage application to the vibration wave motor 1 is not stopped, but the frequency of the drive signal is changed to the holding frequency f0. As a result, it is possible to reduce abnormal noise that occurs when a voltage is applied again after the voltage application is stopped.

  FIG. 5 is a block diagram relating to a driving apparatus according to an embodiment of the present invention. The drive device 90 illustrated in FIG. 5 includes the vibration wave motor 1 and a drive circuit 80. The drive circuit 80 includes a control unit 81, an oscillation unit 82, a phase shift unit 83, amplification units 84a and 84b, a detection unit 85, and a temperature measurement unit 86.

  The oscillation unit 82 oscillates a signal having a frequency set by the control unit 81. The phase shift unit 83 generates an A phase signal and a B phase signal based on the oscillation signal oscillated by the oscillation unit 82. The phase difference between the A phase signal and the B phase signal is set by the control unit 81.

  The amplifying unit 84 a amplifies (boosts) the voltage amplitude of the A-phase signal generated by the phase shifting unit 83 to the voltage set by the control unit 81. As a result, an A-phase drive signal is generated. The amplifying unit 84 b amplifies (boosts) the voltage amplitude of the B-phase signal generated by the phase shifting unit 83 to the voltage set by the control unit 81. As a result, a B-phase drive signal is generated.

  The vibrating body 161 is driven based on the A-phase drive signal amplified by the amplifying unit 84a and the B-phase drive signal amplified by the amplifying unit 84b. The detection unit 85 includes an optical encoder, a magnetic encoder, and the like, detects the position and speed of the lens group L driven by driving the moving body 162, and uses these detection values as electrical signals (detection signals). 81. The control unit 81 acquires information related to the position and speed of the lens group L based on the detection signal from the detection unit 85.

  The temperature measurement unit 86 measures the temperature of the vibration wave motor 1. The temperature of the vibration wave motor 1 rises due to heat generated by the friction between the vibrating body 161 and the moving body 162. An increase in temperature of the vibration wave motor 1 adversely affects its driving ability. The temperature measurement unit 86 outputs the measured temperature signal to the control unit 81. Based on the temperature signal, the controller 81 estimates the influence of the temperature of the vibration wave motor 1 on the driving capability.

  The control unit 81 acquires a drive instruction regarding the moving direction and moving amount of the lens group L from the CPU 3 of the lens barrel 2. The control unit 81 sets the frequency set for the oscillation unit 82, the phase difference set for the phase shift unit 83, and the amplification so that the lens group L is positioned at a target position determined based on the drive instruction. The voltage amplitude set for the portions 84a and 84b is controlled. In addition, the drive instruction | indication which the control part 81 acquires is not limited only to the thing regarding the combination of a movement direction and a movement amount. For example, a movement speed or a movement sequence pattern (for example, the number of wobbling operations) may be included. Further, the driving instruction acquired by the control unit 81 may be a combination of a moving direction and a moving speed.

  The drive control of the vibration wave motor 1 according to the present invention will be described with reference to FIGS. 6 and 7A to 7C. FIG. 6 is an example of a flowchart regarding drive control of the vibration wave motor 1. FIGS. 7A to 7C are examples of timing charts related to drive control of the vibration wave motor 1. FIG. 7A is a timing chart regarding the phase difference between the A-phase and B-phase drive signals. FIG. 7B is a timing chart regarding the oscillation frequency of the oscillation unit 82, that is, the frequency of the drive signal. FIG. 7C is a timing chart regarding the rotational speed of the vibration wave motor 1.

  The processing in FIG. 6 starts executing when the control unit 81 obtains a drive instruction. In step S100, the control unit 81 sets the holding frequency f0 for the oscillating unit 82 and controls the oscillation unit 82 to oscillate the signal having the holding frequency f0.

  In step S110, the control unit 81 sets a phase difference of + 90 ° or −90 ° with respect to the phase shift unit 83, and the phase difference between the A phase signal and the B phase signal output from the phase shift unit 83 is set. Are changed (timing T0 to T1, timing T3 to T4 in FIG. 7). When the frequency at which the oscillating unit 82 oscillates is the holding frequency f0, the rotational speed of the vibration wave motor 1 is substantially zero. Therefore, even if the control unit 81 changes the phase difference in step S110, the driving of the vibration wave motor 1 does not become unstable.

  After the change of the phase difference in step S110 is completed, in step S120, the control unit 81 measures the position and speed of the lens group L calculated from the drive instruction, the detection signal from the detection unit 85, and the temperature measurement unit 86. Based on the temperature of the vibration wave motor 1 and the individual difference between the vibration wave motors 1 and the like, the frequency set for the oscillating unit 82 is controlled so that the lens group L is positioned at the target position. (Timing T1 to T2 in FIG. 7).

  When the frequency set for the oscillating unit 82 is lower than the holding frequency f0, the rotational speed of the vibration wave motor 1 becomes greater than zero. Since the voltage application to the vibration wave motor 1 is not stopped when the vibration wave motor 1 is stopped, no abnormal noise is generated even when the vibration wave motor 1 starts driving.

  In step S130, the control unit 81 determines whether or not the lens group L has reached the target position. Control unit 81 advances the process to step S120 when step S130 is negatively determined, and advances the process to step S140 when step S130 is positively determined.

  In step S140, the control unit 81 sets the holding frequency f0 for the oscillating unit 82 and controls the oscillating unit 82 to oscillate a signal having the holding frequency f0 (timing T2 to T3 in FIG. 7).

  In step S150, the control unit 81 determines whether or not the next drive instruction has been acquired. Control unit 81 advances the process to step S110 if step S150 is affirmed, and advances the process to step S160 if step S150 is negative.

  In step S160, the control unit 81 sets a phase difference of 0 ° with respect to the phase shift unit 83, and changes the phase difference between the A phase signal and the B phase signal output from the phase shift unit 83. Then, the process of FIG. Thereby, as shown in FIG. 3, the rotational speed of the vibration wave motor 1 is controlled to be zero even by the phase difference.

  As shown in FIG. 4, the holding frequency f0 has a range of possible values. In step S140, the effect obtained with respect to the vibration wave motor 1 varies depending on the value within the range of the holding frequency f0 set by the control unit 81 in the oscillation unit 82. The difference in effect will be described with reference to FIG.

  FIG. 8 is a diagram illustrating the frequency-vibration deformation characteristics of the vibrating body 161. In FIG. 8, the natural frequency f9 of the ninth-order bending vibration of the vibrating body 161 is illustrated at a position of 26 kHz, and the natural frequency f10 of the tenth-order bending vibration is illustrated at a position of 32 kHz. Hereinafter, the natural frequency f9 of the ninth-order bending vibration is simply abbreviated as the natural frequency f9, and the natural frequency f10 of the tenth-order bending vibration is simply abbreviated as the natural frequency f10.

  When the frequency of the drive signal is in the vicinity of the natural frequency f9 of the ninth bending vibration, nine traveling waves are generated on the drive surface 123 of the vibrating body 161. When the frequency of the drive signal is in the vicinity of the natural frequency f10 of the 10th-order bending vibration, ten traveling waves are generated on the drive surface 123 of the vibrating body 161. Of the magnitude of the vibration of the vibrating body 161, the traveling wave components of the nine peaks become smaller as the frequency is farther from the natural frequency f9. Similarly, the traveling wave components of 10 peaks in the magnitude of the vibration of the vibrating body 161 become smaller as the frequency goes away from the natural frequency f10.

  As described above, the piezoelectric body 161b has an electrode pattern that easily excites nine traveling waves, and the vibration wave motor 1 is driven when nine traveling waves are used rather than ten traveling waves. Efficiency is good. Therefore, in FIG. 8, the magnitude of the vibration of the nine traveling waves is larger than the magnitude of the vibration of the ten traveling waves.

  When the phase difference between the two-phase drive signals is the same, the rotational directions of the nine traveling waves and the ten traveling waves are opposite to each other. For example, when the phase difference between two-phase driving signals is + 90 °, the moving body 162 rotates in the forward direction when the frequency of the driving signal is 27 kHz, and the moving body 162 rotates in the reverse direction when the frequency of the driving signal is 33 kHz. Rotate. When the frequency is between the natural frequency f9 and the natural frequency f10, the rotation of the moving body 162 by the nine traveling wave components and the rotation of the moving body 162 by the ten traveling wave components cancel each other.

(1) When the holding frequency f0 is an average value of the natural frequency f9 and the natural frequency f10 When the holding frequency f0 is an average value of the natural frequency f9 and the natural frequency f10, for example, when the holding frequency f0 is 29 kHz in the example of FIG. The magnitude of vibration of the vibrating body 161 is reduced. This is because, in the middle of the natural frequency f9 and the natural frequency f10, both the traveling wave component of 9 peaks and the traveling wave component of 10 peaks are small. Furthermore, the rotation of the moving body 162 due to the traveling wave component of nine peaks and the rotation of the moving body 162 due to the traveling wave component of ten peaks cancel each other.

  Therefore, when the holding frequency f0 is an average value of the natural frequency f9 and the natural frequency f10, the magnitude of the vibration of the vibrating body 161 is small and the moving body 162 is not separated from the vibrating body 161. No abnormal noise is generated due to the collision. In addition, since the rotation of the moving body 162 due to the traveling wave component of nine peaks and the rotation of the moving body 162 due to the traveling wave component of ten peaks cancel each other, the certainty of stopping the rotation of the moving body 162 is increased.

(2) When the holding frequency f0 is higher than the average value of the natural frequency f9 and the natural frequency f10 When the holding frequency f0 is higher than the average value of the natural frequency f9 and the natural frequency f10, that is, closer to the natural frequency f10 than the natural frequency f9. In this case, the traveling wave component generated by the vibrating body 162 is dominated by the traveling wave components of 10 peaks. The moving body 162 that has been rotated based on the traveling wave components of nine peaks in step S120 of FIG. 6 is controlled based on the traveling wave components of ten peaks when the drive frequency is changed to the holding frequency f0 in step S140. In other words, since the rotation by the traveling wave component of 10 peaks is opposite to the rotation by the traveling wave component of 9 peaks, the rotation direction of the moving body 162 in step S140 is the rotation direction at the time of the control in the immediately preceding step S120. The opposite direction. However, since the torque generated by the vibration wave motor 1 at this time is small, the fork 154, the cam ring 153, and the AF ring 152 do not rotate.

  Therefore, when there is a next drive instruction in step S150, if it is determined that the moving body 162 is rotated in the reverse direction in the next drive instruction, the play between the protrusion 155a and the fork 154, the key The play between the groove 153a and the fixing pin 152a is clogged. Thereby, the mechanical collision sound when the moving body 162 actually starts to rotate in the reverse direction can be suppressed.

(3) When the holding frequency f0 is lower than the average value of the natural frequency f9 and the natural frequency f10 When the holding frequency f0 is lower than the average value of the natural frequency f9 and the natural frequency f10, that is, the natural frequency f9 from the natural frequency f10. In the case where the traveling wave is close to, the traveling wave component generated by the vibrating body 162 is dominated by nine traveling wave components. In this case, in step S140, the rotation direction of the moving body 162 is the same as the rotation direction at the time of control in the immediately preceding step S120. Therefore, when there is a next drive instruction in step S150, if it is determined that the moving body 162 is rotated in the same direction in the next drive instruction, the play between the protrusion 155a and the fork 154, the key The play between the groove 153a and the fixing pin 152a is clogged. Thereby, the mechanical collision noise when the moving body 162 actually starts to rotate in the same direction can be suppressed.

  Further, since the holding frequency f0 is closer to the natural frequency f9 than in the cases (1) and (2), the period of the timings T2 to T3 in FIG. 7 can be shortened than in the cases (1) and (2). . Thereby, the processing time in the drive control of the mobile body 162 is shortened, and the stop accuracy of the mobile body 162 is improved.

  As described in (2) above, when the next drive instruction is driven in the direction opposite to the previous drive instruction, the holding frequency f0 should be higher than the average value of the natural frequency f9 and the natural frequency f10. Good. Further, as described in (3) above, when the next drive instruction is driven in the same direction as the previous drive instruction, the holding frequency f0 is set lower than the average value of the natural frequency f9 and the natural frequency f10. Better.

  FIG. 9 is a flowchart regarding the process of step S140 of FIG. In the process of FIG. 9, the holding frequency is appropriately set based on the next drive instruction executed after the drive instruction is executed.

  In step S141, the control unit 81 determines whether or not the next drive instruction has been acquired. If the determination at step S141 is affirmative, the control unit 81 proceeds to step S142. If the determination at step S141 is negative, the control unit 81 proceeds to step S143.

  In step S142, the control unit 81 determines whether or not the next drive instruction is an instruction to rotate the moving body 162 in the same direction as the drive instruction completed immediately before. If the determination at step S142 is affirmative, the control unit 81 proceeds to step S145. If the determination at step S142 is negative, the control unit 81 proceeds to step S144.

In step S143, the control unit 81 sets the holding frequency f0 to an average value of the natural frequency f9 and the natural frequency f10. Thereby, the effect as described in the above (1) is obtained.
In step S144, the control unit 81 sets the holding frequency f0 to a frequency that is higher than the average value of the natural frequency f9 and the natural frequency f10 and lower than the natural frequency f10. Thereby, the effect as described in the above (2) can be obtained.
In step S145, the control unit 81 sets the holding frequency f0 to a frequency that is lower than the average value of the natural frequency f9 and the natural frequency f10 and higher than the natural frequency f9. Thereby, the effect as described in the above (3) is obtained.

  In step S146, the control unit 81 sets the holding frequency f0 set in steps S143 to S145 in the oscillation unit 82.

According to the embodiment described above, the following operational effects can be obtained.
A driving device 90 that drives the lens group L in the lens barrel 2 includes a driving circuit 80 and the vibration wave motor 1. The drive circuit 80 generates A-phase and B-phase drive signals. The vibration wave motor 1 includes a vibrating body 161 and a moving body 162. The vibrating body 161 includes a piezoelectric body 161b to which A-phase and B-phase driving signals generated by the driving circuit 80 are applied, and a traveling wave is generated on the driving surface 123 of the elastic body 161a by the vibration of the piezoelectric body 161b. Then, a driving force for driving the movable body 162 brought into pressure contact is generated. The drive circuit 80 includes a control unit 81 that sets the frequency and phase difference between the A-phase and B-phase drive signals, and maintains the frequency at which the oscillation unit 82 oscillates when the drive direction of the moving body 162 is changed. After setting to f0 (steps S100 and S140 in FIG. 6), the phase difference set in the phase shifter 83 is changed (step S110 in FIG. 6).
By doing in this way, in the drive device 90, when switching the drive direction of the mobile body 162, since the drive of the mobile body 162 is stopped by control of a drive frequency, generation | occurrence | production of abnormal noise can be suppressed. .

  If the phase difference is changed while the moving body 162 is being driven, the rotation of the moving body 162 becomes unstable, and there is a possibility that abnormal noise is generated due to the collision between the moving body 162 and the vibrating body 161. However, if the phase difference between the A-phase and B-phase drive signals is controlled with the driving of the moving body 162 stopped as in the present invention, such abnormal noise may occur. Absent.

  In addition, if the phase difference is changed while the moving body 162 is being driven, the moving body 162 may be temporarily driven at a low speed. However, the rotation unevenness of the moving body 162 increases during low speed driving, and the stopping accuracy is increased. There is a risk that it cannot be secured. However, if the phase difference between the A-phase and B-phase drive signals is controlled in a state where the driving of the moving body 162 is stopped as in the present invention, such an increase in rotation unevenness may occur. Therefore, there is no possibility that the stop accuracy cannot be secured.

The embodiment described above can be implemented with the following modifications.
(Modification 1) In the above-described embodiment, assuming that the piezoelectric body 161b has an electrode pattern in which nine traveling waves are likely to be generated, nine traveling waves or ten mountains on the driving surface 123 of the vibrating body 161. It is assumed that a traveling wave of However, the traveling wave generated by the vibrating body 161 is not limited to nine traveling waves. In the present invention, the driving surface 123 may be caused to generate n-order bending vibration due to traveling waves of arbitrary n peaks.
(Modification 2) In the above-described embodiment, the phase difference between the A-phase and B-phase drive signals is controlled while the lens group L is being driven and controlled by controlling the frequency set for the oscillator 82. I did not. However, driving control of the lens group L by controlling the frequency set for the oscillating unit 82 within a range in which abnormal noise due to the collision between the moving body 162 and the vibrating body 161 and an increase in rotation unevenness of the moving body 162 can be ignored. The phase difference between the drive signals for the A phase and the B phase may be controlled even during the operation.

  The embodiments and modifications described above are merely examples, and the present invention is not limited to these contents as long as the features of the invention are not impaired. Further, the embodiments and modifications described above may be combined and executed as long as the features of the invention are not impaired.

DESCRIPTION OF SYMBOLS 1 Vibration wave motor 2 Lens barrel 80 Drive circuit 81 Control part 82 Oscillation part 83 Phase shift part 84a, 84b Amplification part 90 Drive apparatus 161 Vibration body 162 Moving body f0 Holding frequency f9, f10 Natural frequency

Claims (5)

A signal generator for generating a pair of drive signals;
An electromechanical transducer to which the drive signal generated by the signal generator is applied;
A vibrating body that generates a driving force by vibration of the electromechanical transducer;
A movable body that is brought into pressure contact with the vibrating body and driven by the driving force;
A control unit for setting the frequency and phase difference of the drive signal;
With
The control unit, when changing the driving direction of the moving body, changes the phase difference after setting the frequency to a holding frequency at which the driving speed of the moving body is substantially zero. Drive device. The drive device according to claim 1,
The controller sets an average value of the natural frequency fn of the n-th order vibration and the natural frequency fn + 1 of the n + 1-order vibration as the holding frequency. The drive device according to claim 1 or 2,
The control unit has, as the holding frequency, a frequency that is higher than the average value of the natural frequency fn of the nth-order vibration and the natural frequency fn + 1 of the n + 1st order vibration and lower than the natural frequency fn + 1, or lower than the average value. A drive device that sets a frequency that is higher than the natural frequency fn. The drive device according to claim 3, wherein
When the next driving direction of the moving body is the same as the previous driving direction, the control unit sets a frequency lower than the average value and higher than the natural frequency fn as the holding frequency. When the driving direction is opposite to the immediately preceding driving direction, a frequency that is higher than the average value and lower than the natural frequency fn + 1 is set.   A lens barrel comprising the drive device according to claim 1.

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