JP2009047791A - Actuator controller, lens barrel, and optical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator controller capable of performing highly accurate control regardless of variations in an individual product or an environmental change, and to provide a lens barrel and an optical device having the controller. <P>SOLUTION: The actuator controller includes: a driving section 12 which outputs a drive signal to an actuator 9; a detecting section 10 which detects the driving speed of the actuator 9; a storage means 16 which stores characteristic data indicating a relationship between the frequency of a drive signal and a driving speed; a control section 14 which controls a drive signal output from the driving section 12 on the basis of the characteristic data stored in the storage means 16; and an updating means S8 which operates the driving section 12 and the detecting section 10 after powered on but before the control by the control section 14 starts and updates the characteristic data stored in the storage means 16. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an actuator control device, a lens barrel, and an optical device.

  For example, an ultrasonic motor is used in an autofocus drive mechanism of a lens barrel of a camera. The ultrasonic motor has a stator having a piezoelectric body and a movable body that performs a rotational movement, and moves by applying a voltage having a frequency (driving frequency) in an ultrasonic range exceeding 20 kHz to the piezoelectric body. The child rotates. In the ultrasonic motor, the rotational speed increases exponentially as the driving frequency is lowered.

  Ideally, the number of rotations of the ultrasonic motor should correspond one-to-one with the drive frequency. However, in practice, there are variations in the individual ultrasonic motors, and the object to be driven by the ultrasonic motors is different. The correspondence between the rotational speed and the drive frequency also changes depending on the load. In addition, the relationship between the oscillation frequency generated by the voltage controlled oscillator (VCO) itself that generates the drive frequency with respect to the input voltage also varies.

  Therefore, as shown in Patent Document 1 below, a technique has been developed in which a correction coefficient is obtained from the difference between the standard drive characteristic of the motor and the actual drive characteristic, and the motor is controlled based on the standard drive characteristic and the correction coefficient. ing.

However, in the apparatus shown in Patent Document 1, the correction coefficient is not calculated with the lens barrel attached to the camera body, but is used as a special lens adjustment apparatus for calculating the correction coefficient. It is calculated by attaching. Therefore, a special device for calculating the correction coefficient is required, and the work is complicated. For this reason, it is difficult for the apparatus shown in Patent Document 1 to cope with changes in motor characteristics due to environmental changes such as the environmental temperature when the camera is used.
JP 2003-219668 A

  The present invention has been made in view of such a situation, and an object of the present invention is to provide an actuator control device that can be controlled with high accuracy without depending on individual product variations and environmental changes, and a lens barrel having the control device, and An optical device is provided.

In order to achieve the above object, an actuator control device according to the first aspect of the present invention provides:
A drive unit (12) for outputting a drive signal to the actuator (9);
A detector (10) for detecting the driving speed of the actuator;
Storage means (16) for storing characteristic data indicating the relationship between the frequency of the drive signal and the drive speed;
A control unit (14) for controlling the drive signal output from the drive unit based on the characteristic data stored in the storage unit;
Update means (S8) for operating the drive section and the detection section and updating the characteristic data stored in the storage section after the power is turned on and before starting the control by the control section. It is provided with.

  In the actuator control device according to the first aspect of the present invention, the characteristic data stored in the storage means is updated after the power is turned on and before the control is started, and based on the updated characteristic data. Control the actuator. Therefore, it becomes possible to control the actuator with high accuracy irrespective of variations in individual actuator products and environmental changes. Moreover, the present invention does not require a special device for calculating the correction coefficient.

  Preferably, the control unit (14) starts the control after input of an external command signal and after the processing by the updating means is completed. Since the control does not start when the update by the update means does not end, the control always starts based on the latest update data.

  Preferably, the control unit (14) outputs a signal indicating that the control by the control unit cannot be performed when the command signal is input before the processing by the updating unit is completed. Convenience is improved by notifying the operator of the device that control cannot be performed.

  Preferably, the updating means (S8) updates the characteristic data every time the power is turned on. In that case, every time the power is turned on, high-precision control based on the latest characteristic data is always possible.

  Preferably, the update means (S8) performs control to change the frequency of the drive signal output from the drive unit, and determines the drive signal until the drive speed detected by the detection unit reaches a predetermined value. The characteristic data is updated based on the relationship between the frequency and the driving speed. In particular, in an ultrasonic motor, the drive speed changes based on the change in the frequency of the drive signal, and therefore, accurate control is possible by updating the characteristic data based on the relationship between the frequency of the drive signal and the drive speed. .

An actuator control device according to the second aspect of the present invention provides:
A drive unit (12) for outputting a drive signal to the actuator;
A detector (10) for detecting the driving speed of the actuator;
Storage means (16) for storing characteristic data indicating the relationship between the frequency of the drive signal and the drive speed;
A control unit (14) for controlling a drive signal output from the drive unit on the basis of the characteristic data stored in the storage unit by an input of an external command signal;
Update means (S18) for detecting the drive speed by the detection section and updating the characteristic data stored in the storage section when the drive signal is controlled by the control section. It is characterized by that.

  In the actuator control device according to the second aspect of the present invention, when the drive signal is controlled by the control unit, the characteristic data stored in the storage unit is updated, and based on the updated characteristic data, Control the actuator. Therefore, it becomes possible to control the actuator with high accuracy irrespective of variations in individual actuator products and environmental changes. Moreover, the present invention does not require a special device for calculating the correction coefficient.

  Preferably, the updating means (S18) updates the characteristic data every predetermined time. By updating the characteristic data every predetermined time, it becomes possible to control the actuator with high accuracy based on the latest characteristic data at all times.

Preferably, the actuator control device of the present invention further includes a temperature sensor,
The updating means (S18) updates the characteristic data when the temperature change detected by the temperature sensor becomes a predetermined value or more. By updating the characteristic data according to the temperature change, it becomes possible to control the actuator with high accuracy regardless of the temperature environment change.

  Preferably, the update means (S18) updates the characteristic data based on a relationship between the drive speed and the drive speed until the drive speed detected by the detection unit reaches a predetermined value. . By detecting and updating the characteristic data in a wide range until the driving speed reaches a predetermined value, the control accuracy is further improved.

The actuator control device according to the third aspect of the present invention is:
A drive unit (12) for outputting a drive signal to the actuator;
A detector (10) for detecting the driving speed of the actuator;
Storage means (16) in which first characteristic data indicating the relationship between the frequency of the drive signal and the drive speed is stored in advance;
Characteristic data acquisition means (S28, S29) for changing the frequency of the drive signal output from the drive unit and obtaining second characteristic data from the relationship with the drive speed detected by the detection unit;
A control unit (12) for controlling the frequency of the drive signal output from the drive unit based on the first characteristic data and the second characteristic data is provided.

  In the actuator control apparatus according to the third aspect of the present invention, the actuator is controlled based on the first characteristic data stored in advance and the second characteristic data that changes according to the variation or environment of each product. To do. Therefore, it becomes possible to control the actuator with high accuracy irrespective of variations in individual actuator products and environmental changes. Moreover, the present invention does not require a special device for calculating the correction coefficient.

  Preferably, the second characteristic data is data of the driving speed corresponding to the driving signals having at least two frequencies. For example, the data amount can be reduced by using only two points of data of the drive frequency data in the low-speed side measurement area and the drive frequency data in the high-speed side measurement area. Therefore, the capacity of the storage means for storing data can be reduced.

  Preferably, the control unit corrects the first characteristic data based on the second characteristic data. Control accuracy is improved by performing control based on the corrected first characteristic data.

  Preferably, the characteristic data acquisition unit (S28, S29) is configured to perform the first step based on a relationship between the drive speed and the frequency of the drive signal until the drive speed detected by the detection unit reaches a predetermined value. 2 characteristic data is obtained. By obtaining the second characteristic data in a wide range until the driving speed reaches a predetermined value, the reliability of the second characteristic data is improved.

  A lens barrel according to the present invention includes the actuator control device according to any one of the above.

  An optical device according to the present invention includes the actuator control device according to any one of the above.

  In the above description, in order to explain the present invention in an easy-to-understand manner, the description has been made in association with the reference numerals of the drawings showing the embodiments, but the present invention is not limited to this. The configuration of the embodiment described later may be improved as appropriate, or at least a part of the configuration may be replaced with another component. Further, the configuration requirements that are not particularly limited with respect to the arrangement are not limited to the arrangement disclosed in the embodiment, and can be arranged at a position where the function can be achieved.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
FIG. 1 is a schematic perspective view of a camera according to an embodiment of the present invention.
2 is a control block diagram of an ultrasonic motor used for the lens barrel of the camera shown in FIG.
3 is a flowchart of the control circuit shown in FIG.
FIG. 4 is a graph showing the relationship between the drive frequency and the rotational speed in the flowchart shown in FIG.
FIG. 5 is a flowchart of a control circuit according to another embodiment of the present invention.
FIG. 6 is a graph showing the relationship between the drive frequency and the rotational speed in the flowchart shown in FIG.
FIG. 7 is a flowchart of a control circuit according to still another embodiment of the present invention.
FIG. 8 is a graph showing the relationship between the drive frequency and the rotation speed in the flowchart shown in FIG.
First embodiment

  As shown in FIG. 1, a digital single lens reflex camera 2 according to an embodiment of the present invention includes a camera body 4 and a lens barrel 6 that is detachably attached to the camera body 4. A subject image incident from the lens barrel 6 can be viewed through a finder (not shown) on the back of the camera body 4.

  The camera body 4 and the lens barrel 6 are driven by a battery (not shown) built in the camera body 4 as a driving power source, and the release button 8 provided on the upper surface of the camera body 4 is half-pressed, whereby the lens barrel The lens group in 6 moves in the optical axis direction and performs operations such as autofocus.

  The camera body 4 and the lens barrel 6 incorporate an MCU (not shown) for controlling each of them. Between the camera body 4 and the lens barrel 6, a communication circuit 18 (see FIG. 2) for connecting signal lines for performing data communication between the MCUs is provided.

  By making the release button 8 shown in FIG. 1 half-pressed, the MCU in the camera body 4 is controlled by a control circuit (for example, MCU) 14 in the lens barrel 6 connected via the communication circuit 18 shown in FIG. A drive instruction is issued. The control circuit 14 in the lens barrel 6 receives a driving instruction and drives the ultrasonic motor 9 via the driving circuit 12 to drive a focusing lens (not shown).

  As shown in FIG. 2, the actuator control apparatus according to the present embodiment includes a drive circuit 12 for the ultrasonic motor 9, a control circuit 14, a memory 16 including a nonvolatile memory (EEPROM), and the ultrasonic motor 9. And a speed detector 10 for detecting the rotational speed of the motor.

  The control circuit 14 performs the control shown in FIG. 3, for example. That is, in step S1, when the control circuit 14 shown in FIG. 2 detects that the camera 2 shown in FIG. 1 is turned on, initialization is performed in step S2. Next, in step S3, a drive signal is output from the control circuit 14 shown in FIG. 2 to the drive circuit 12, and the drive of the ultrasonic motor 9 by the drive circuit 12 is started. At the start of driving, as shown in FIG. 4, the driving frequency f is the initial frequency f0. The initial frequency f0 is not particularly limited, but is, for example, 30 kHz ± 1 kHz.

  The drive frequency f applied to the ultrasonic motor 9 from the drive circuit 12 shown in FIG. 2 decreases monotonously from the initial frequency f0 as shown in FIG. The drive frequency f applied to the ultrasonic motor 9 from the drive circuit 12 is read into the control circuit 14 in step S4 shown in FIG. In the ultrasonic motor 9 shown in FIG. 2, as shown in FIG. 4, the rotation speed (rotation speed) N starts to increase after a predetermined response delay time Δt after the drive frequency f is applied. The response delay time Δt is, for example, 10 milliseconds.

  In the ultrasonic motor 9, the rotation speed N increases as the drive frequency decreases. The rotational speed of the ultrasonic motor 9 is measured by the speed detector 10 shown in FIG. 2, and the rotational speed N is monitored by the control circuit 14 in step S5 shown in FIG. Next, in step S6 shown in FIG. 3, it is determined whether or not the rotational speed N monitored by the control circuit 14 is Nmax or more.

  If the rotational speed N monitored by the control circuit 14 is smaller than Nmax, the drive frequency f output from the drive circuit 12 shown in FIG. Returning to step S3, steps S4 to S6 are repeated.

  In step S6, when the rotational speed N becomes equal to or greater than Nmax, as shown in FIG. 4, the measurement of the rotational speed is terminated, and the process goes to step S8 shown in FIG. Characteristic data indicating the relationship is stored in the memory 16 shown in FIG. In the storage, the old characteristic data is updated to the new characteristic data and stored. Specifically, the frequency measurement period t1 is made to coincide with the rotation speed measurement period t0 shown in FIG. 4, the drive frequency f and the rotation speed N in the meantime are matched, and the data is used as actual fN characteristic data. The memory 16 is updated and stored.

  The rotation speed measurement period t0 is not particularly limited, but is, for example, 1 to 2 seconds. The drive frequency f1 after the frequency measurement period t1 is, for example, about 25 kHz.

  In step S9 shown in FIG. 3, the ultrasonic motor shown in FIG. 2 is driven based on the actual fN characteristic data stored in the memory 16, and the lens group in the lens barrel 6 shown in FIG. Move in the direction and perform automatic focusing operation.

  In the actuator control apparatus according to the present embodiment, after the power is turned on in step S3 shown in FIG. 3, the actual operation stored in the memory 16 shown in FIG. 2 is started before the normal operation control in step S9 is started. The fN characteristic data is updated, and the ultrasonic motor 9 is controlled based on the updated characteristic data. Therefore, it is possible to control the ultrasonic motor 9 with high accuracy regardless of variations in individual ultrasonic motor 9 products and environmental changes. In addition, this embodiment does not require a special device for calculating the correction coefficient.

  In the present embodiment, the control circuit 14 shown in FIG. 2 sends the release button from the camera body 4 shown in FIG. 1 via the communication circuit 18 before the update and storage of the characteristic data in step S8 shown in FIG. When a half-press signal of 8 is received, the following control is performed. That is, the control circuit 14 shown in FIG. 2 sends a signal to the camera body 4 shown in FIG. 1 via the communication circuit 18, and “data update” or the like is displayed on the display screen attached to the back of the camera body 4. Is displayed to inform the operator that normal control such as focusing cannot be performed.

  For this reason, in the present embodiment, when the update of characteristic data in step S8 shown in FIG. 3 is not completed, the normal operation control in step S9 is not started, so that the control is always started based on the latest update data.

In the present embodiment, the actual fN characteristic data is updated every time the camera 2 shown in FIG. 1 is turned on. Therefore, every time the power is turned on, highly accurate control based on the latest actual fN characteristic data can be performed.
Second embodiment

  The actuator control apparatus according to the present embodiment is different from the first embodiment only in the operation of the control circuit 14 shown in FIG. 2, and the other configurations and operational effects are the same as those in the case of the first embodiment. is there. Hereinafter, a different part from 1st Embodiment is demonstrated in detail, and description of a common part is abbreviate | omitted.

  As shown in FIG. 5, in this embodiment, when the control circuit 14 shown in FIG. 2 detects the power-on of the camera 2 shown in FIG. 1 in step S11, initialization work is performed in step S12. Next, in step S13, it is detected whether or not a half-press signal of the release button 8 has been received from the camera body 4 shown in FIG. 1 via the communication circuit 18 shown in FIG. When the half-press signal is detected, the process goes to step S14 shown in FIG. 5 to output a normal drive signal from the control circuit 14 shown in FIG. 2 to the drive circuit 12, and the drive circuit 12 performs normal drive of the ultrasonic motor 9. To start.

  At the start of driving, as shown in FIG. 6, the driving frequency f is the initial frequency f0. The drive frequency f applied to the ultrasonic motor 9 from the drive circuit 12 shown in FIG. 2 is read into the control circuit 14 in step S15 shown in FIG. In the ultrasonic motor 9 shown in FIG. 2, as shown in FIG. 6, the rotational speed (rotational speed) N starts to increase after a predetermined response delay time Δt after the drive frequency f is applied.

  In the ultrasonic motor 9, the rotation speed N increases as the drive frequency decreases. The rotational speed of the ultrasonic motor 9 is measured by the speed detector 10 shown in FIG. 2, and the rotational speed N is monitored by the control circuit 14 in step S16 shown in FIG. Next, in step S17 shown in FIG. 5, it is determined whether or not the rotational speed N monitored by the control circuit 14 is equal to or greater than Nmax.

  When the rotation speed N monitored by the control circuit 14 is smaller than Nmax, the process returns to step S14, and steps S14 to S17 are repeated to continue normal control operations such as a focusing operation.

  In step S17, when the rotational speed N becomes Nmax or more, as shown in FIG. 6, the measurement of the rotational speed is terminated, and the process goes to step S18 shown in FIG. Characteristic data indicating the relationship is stored in the memory 16 shown in FIG. In the storage, the old characteristic data is updated to the new characteristic data and stored. Specifically, the frequency measurement period t1 is made to coincide with the rotation speed measurement period t0 shown in FIG. 6, and the drive frequency f and the rotation speed N in the meantime are made to correspond to each other as the actual fN characteristic data. The memory 16 is updated and stored.

  In step S19 shown in FIG. 5, the ultrasonic motor shown in FIG. 2 is driven based on the actual fN characteristic data stored in the memory 16, and the lens group in the lens barrel 6 shown in FIG. Move in the direction and continue the auto-focusing operation.

  In the actuator control apparatus according to the present embodiment, the actual fN characteristic data stored in the memory 16 is stored when normal control of the ultrasonic motor 9 is performed by the control circuit 14 and the drive circuit 12 shown in FIG. The ultrasonic motor 9 is controlled based on the updated characteristic data. Therefore, it is possible to control the ultrasonic motor 9 with high accuracy regardless of variations in individual ultrasonic motor 9 products and environmental changes. In addition, this embodiment does not require a special device for calculating the correction coefficient.

  In this embodiment, every time a half-press signal is detected in step S13 shown in FIG. 5, the actual f-N characteristic data is not updated and stored in step S18, but the actual f-N -N characteristic data may be updated and stored. That is, in step S13, whether or not the predetermined time has elapsed is repeatedly detected, and the characteristic data may be updated only in that case. In this case, the actuator can be controlled with high accuracy based on the latest characteristic data at all times, and the data is not updated every time the button is half-pressed, so that the automatic focusing operation is quickened.

Furthermore, in this embodiment, either the camera body 4 or the lens barrel 6 shown in FIG. 1 is provided with a temperature sensor, and temperature data detected by the temperature sensor is input to the control circuit 14 shown in FIG. You may make it let it. That is, every time a half-press signal is detected in step S13 shown in FIG. 5, the actual fN characteristic data is not updated and stored in step S18, but the temperature change detected by the temperature sensor is greater than or equal to a predetermined value. Only when it becomes, the actual fN characteristic data may be updated and stored. That is, in step S13, whether the temperature change detected by the temperature sensor is equal to or greater than a predetermined value is detected repeatedly, and only in that case, the characteristic data may be updated. In that case, by updating the characteristic data according to the temperature change, it becomes possible to control the actuator with high accuracy regardless of the change in the temperature environment, and the data is not updated every time the button is half-pressed. Automatic focusing operation is quick.
Third embodiment

  The actuator control apparatus according to the present embodiment is different from the first embodiment only in the operation of the control circuit 14 shown in FIG. 2, and the other configurations and operational effects are the same as those in the case of the first embodiment. is there. Hereinafter, a different part from 1st Embodiment is demonstrated in detail, and description of a common part is abbreviate | omitted.

  As shown in FIG. 7, in this embodiment, when the control circuit 14 shown in FIG. 2 detects the power-on of the camera 2 shown in FIG. 1 in step S21, initialization work is performed in step S22. Next, in step S23, a drive signal is output from the control circuit 14 shown in FIG. 2 to the drive circuit 12, and the drive of the ultrasonic motor 9 by the drive circuit 12 is started. At the start of driving, as shown in FIG. 4, the driving frequency f is the initial frequency f0.

  The drive frequency f applied to the ultrasonic motor 9 from the drive circuit 12 shown in FIG. 2 decreases monotonously from the initial frequency f0 as shown in FIG. The drive frequency f applied to the ultrasonic motor 9 from the drive circuit 12 is read into the control circuit 14 in step S24 shown in FIG. In the ultrasonic motor 9 shown in FIG. 2, as shown in FIG. 4, the rotation speed (rotation speed) N starts to increase after a predetermined response delay time Δt after the drive frequency f is applied.

  In the ultrasonic motor 9, the rotation speed N increases as the drive frequency decreases. The rotational speed of the ultrasonic motor 9 is measured by the speed detector 10 shown in FIG. 2, and the rotational speed N is monitored by the control circuit 14 in step S25 shown in FIG. Next, in step S26 shown in FIG. 7, it is determined whether or not the rotational speed N monitored by the control circuit 14 is Nmax or more.

  If the rotational speed N monitored by the control circuit 14 is smaller than Nmax, the drive frequency f output from the drive circuit 12 shown in FIG. 2 to the ultrasonic motor 9 is lowered in step S27. Returning to step S23, steps S24 to S66 are repeated.

  In step S26, when the rotational speed N becomes Nmax or more, as shown in FIG. 4, the measurement of the rotational speed is stopped, and the process goes to step S28 shown in FIG. Characteristic data indicating the relationship is stored in the memory 16 shown in FIG. When saving, as shown in FIG. 8, not all the actual fN characteristic data curves are saved, but only the two adjustment points of the low speed side measurement area and the high speed side measurement area as follows. The correction value is calculated from the data and the data is updated and stored.

  That is, in the present embodiment, the actual f− is adjusted at two adjustment points of the low speed side measurement area and the high speed side measurement area with respect to the standard fN characteristic data stored in the memory 16 shown in FIG. 2. In consideration of the difference from the N characteristic data, the correction value is calculated in step S29 shown in FIG. 7, and only the correction value is stored. For example, the rotational speed of the low speed side measurement area is 10 rpm, the rotational speed of the high speed side measurement area is 40 rpm, and the actual fN characteristic data is realigned with the standard fN characteristic data.

  For example, it is assumed that standard fN characteristic data is expressed by the following equation (1). In Equation (1), N is the number of revolutions, f is the drive frequency, and G is a function indicating a curve of standard fN characteristic data.

[Equation 1]
N = G (f) (1)

  The correction value includes a shift amount shift in the frequency f direction and a slope γ of the characteristic curve. With these corrections, the actual fN characteristic data is expressed by the following equation (2).

[Equation 2]
N = γ × G (f + shift) (2)

  In step S30 shown in FIG. 7, the ultrasonic motor shown in FIG. 2 is driven based on the standard fN characteristic data in which the correction value shown in equation (2) is incorporated, and the lens barrel 6 shown in FIG. This lens group is moved in the direction of the optical axis to perform an automatic focusing operation.

  In the actuator control apparatus according to the present embodiment, ultrasonic waves are generated based on standard fN characteristic data stored in advance and correction value data (γ, shift) that changes in accordance with the variation or environment of each product. The motor 9 is controlled. Therefore, it is possible to control the ultrasonic motor 9 with high accuracy regardless of variations in individual ultrasonic motor 9 products and environmental changes. In addition, this embodiment does not require a special device for calculating the correction coefficient.

  Further, in the present embodiment, a correction value is calculated from data of only two points, that is, the driving frequency data in the low speed side measurement area and the driving frequency data in the high speed side measurement area, and only the correction value is saved. The amount of data can be reduced. Therefore, the capacity of the storage means for storing data can be reduced.

  The above-described embodiment can be variously modified within the scope of the present invention. For example, the actuator driven by the actuator control device of the above-described embodiment is not limited to an ultrasonic motor, and may be an actuator such as a DC motor.

  The optical device in which the actuator control device of the above-described embodiment is incorporated is not limited to a digital single-lens reflex camera, but may be an optical device such as a film single-lens reflex camera, a digital compact camera, a film compact camera, or a video camera.

FIG. 1 is a schematic perspective view of a camera according to an embodiment of the present invention. FIG. 2 is a control block diagram of an ultrasonic motor used in the lens barrel of the camera shown in FIG. FIG. 3 is a flowchart of the control circuit shown in FIG. FIG. 4 is a graph showing the relationship between the drive frequency and the rotational speed in the flowchart shown in FIG. FIG. 5 is a flowchart of a control circuit according to another embodiment of the present invention. FIG. 6 is a graph showing the relationship between the drive frequency and the rotational speed in the flowchart shown in FIG. FIG. 7 is a flowchart of a control circuit according to still another embodiment of the present invention. FIG. 8 is a graph showing the relationship between the drive frequency and the rotation speed in the flowchart shown in FIG.

Explanation of symbols

2 ... Camera 4 ... Camera body 6 ... Lens barrel 9 ... Ultrasonic motor 10 ... Speed detector 12 ... Drive circuit 14 ... Control circuit 16 ... Memory

Claims (15)

A drive unit that outputs a drive signal to the actuator;
A detection unit for detecting a driving speed of the actuator;
Storage means for storing characteristic data indicating the relationship between the frequency of the drive signal and the drive speed;
A control unit for controlling the drive signal output from the drive unit based on the characteristic data stored in the storage unit;
An update unit that operates the drive unit and the detection unit and updates the characteristic data stored in the storage unit after the power is turned on and before the control by the control unit is started. An actuator control device.   2. The actuator control apparatus according to claim 1, wherein the control unit starts control by the control unit after input of an external command signal and after completion of processing by the updating unit.   3. The actuator according to claim 2, wherein the control unit outputs a signal indicating that control by the control unit cannot be performed when the command signal is input before the processing by the updating unit is completed. Control device.   The actuator control apparatus according to claim 1, wherein the updating unit updates the characteristic data every time the power is turned on.   The update means performs control to change the frequency of the drive signal output from the drive unit, and the frequency of the drive signal and the drive speed until the drive speed detected by the detection unit reaches a predetermined value. The actuator control device according to claim 1, wherein the characteristic data is updated based on the relationship. A drive unit that outputs a drive signal to the actuator;
A detection unit for detecting a driving speed of the actuator;
Storage means for storing characteristic data indicating the relationship between the frequency of the drive signal and the drive speed;
A control unit that controls a drive signal output from the drive unit based on the characteristic data stored in the storage unit by an input of an external command signal;
Update means for detecting the drive speed by the detection unit and updating the characteristic data stored in the storage unit when the control of the drive signal by the control unit is performed. A featured actuator control device.   The actuator control apparatus according to claim 6, wherein the updating unit updates the characteristic data every elapse of a predetermined time. A temperature sensor;
The actuator control apparatus according to claim 6, wherein the update unit updates the characteristic data when a temperature change detected by the temperature sensor becomes a predetermined value or more.   The update means updates the characteristic data based on the relationship between the drive speed and the frequency of the drive signal until the drive speed detected by the detector reaches a predetermined value. Item 9. The actuator control device according to any one of Items 6 to 8. A drive unit that outputs a drive signal to the actuator;
A detection unit for detecting a driving speed of the actuator;
Storage means in which first characteristic data indicating a relationship between the frequency of the drive signal and the drive speed is stored in advance;
Characteristic data acquisition means for changing the frequency of the drive signal output from the drive unit and obtaining second characteristic data from the relationship with the drive speed detected by the detection unit;
An actuator control apparatus comprising: a control unit that controls a frequency of a drive signal output from the drive unit based on the first characteristic data and the second characteristic data.   11. The actuator control device according to claim 10, wherein the second characteristic data is data of the driving speed corresponding to the driving signals having at least two frequencies.   The actuator control device according to claim 10 or 11, wherein the control unit corrects the first characteristic data based on the second characteristic data.   The characteristic data acquisition means obtains the second characteristic data based on a relationship between the driving speed and the frequency of the driving signal until the driving speed detected by the detection unit reaches a predetermined value. The actuator control apparatus according to any one of claims 10 to 12,   A lens barrel having the actuator control device according to claim 1.   An optical device comprising the actuator control device according to claim 1.

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