JPH06165590A - Object driver - Google Patents

Abstract

PURPOSE:To attain operational feeling matched to the feeling of operator by determining the rotational direction of a manual operating member depending on a constant width pulse signal. CONSTITUTION:Upon turning a manual operating member 8, two-phase pulses are outputted in time series from an encoder 7 depending on the rotational angle thereof and the two-phase pulses are fed to a direction decision unit 6. The direction decision unit 6 detects rotational direction of the manual operating member 8 from the two-phase pulses thus received and delivers a signal representative of driving direction of a motor 3 to a drive circuit 4. The direction decision unit 6 also synthesizes the two-phase pulses into a single-phase pulse which is subsequently fed to a constant width pulse generating circuit 5. The constant width pulse generating circuit 5 is triggered by the edge of the single-phase pulse received from the direction decision unit 6 to actuate a timer circuit thus delivering a driving signal having constant width to the drive circuit 4. This constitution provides an operational feeling matched to the feeling of operator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an object driving device such as a power manipulating device for driving an object to be driven by the power of a motor or the like in accordance with an operation amount, an operation speed and an operation direction of a manual operation member.

[0002]

2. Description of the Related Art Conventionally, the following technique has been proposed as a power focus device which detects rotation of a manually operated member which is rotated and drives an optical system by a motor.

In Japanese Patent Laid-Open No. 63-89825, the input to the manually operated member is counted as a pulse signal per rotation angle, and an encoder is provided in a motor for moving a focus member of an optical system, and the above-described count amount or count amount is set. A power focus device has been proposed which drives the motor based on the encoder output of the motor by an amount proportional to.

Japanese Laid-Open Patent Publication No. 1-161325 proposes a power focus device that detects the rotation amount and rotation speed of a manually operated member and switches the drive amount of a motor based on these values.

Japanese Unexamined Patent Publication No. 1-182812 proposes a power focus device that detects the rotational speed of a manually operated member and selectively sets the high and low levels of the motor drive output based on this value.

[0006]

However, in the technique disclosed in Japanese Patent Laid-Open No. 63-89825, it is not possible to switch between the rough adjustment and the fine adjustment at the same time, and it is not possible to achieve both the rapidity and the accuracy of focus.

Further, in the technique disclosed in JP-A-1-161325 and the technique disclosed in JP-A-1-182812, in order to change the drive speed of the motor according to the rotation speed of the manual operation member, the rotation of the manual operation member is performed. It was essential to detect the speed, and a fv converter or timer measurement was absolutely necessary.

Moreover, even when the control is performed by a microcomputer or the like, the determination after the above rotation speed detection is complicated, and a large-scale program is required.

It is an object of the present invention to provide an improved object drive system which overcomes the above mentioned problems of the prior art.

[0010]

An object driving apparatus according to the present invention has constant width pulse signal generating means for generating a constant width pulse signal in response to generation of a pulse signal representing a rotation angle of a manually operated member, and drives the object driving device. The source control means is configured to be controlled by the constant width pulse signal and the output of the manual operation member rotation direction determination means.

[0011]

According to the device of the present invention, the following effects can be obtained.

(1) The drive speed of the motor is arbitrarily changed according to the rotation speed of the operation member, and an operation feeling that matches the sensitivity of the operator can be obtained.

(2) The drive amount of the motor is arbitrarily changed according to the rotation speed of the operating member, and it is not necessary to switch between coarse adjustment and fine adjustment.

(3) It is not necessary to detect the rotational speed of the operating member, and a dedicated circuit such as an fv converter or a timer for measuring the interval is unnecessary. Therefore, the cost of the device can be reduced.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <First Embodiment> FIG. 1 is a block diagram showing a first embodiment of the present invention.

In FIG. 1, 1 is an optical system, 2 is a moving lens group, 3 is a motor which is a drive source for driving the moving lens group, 4 is a drive circuit for driving the motor 3, and 5 is a drive circuit. Constant-width pulse generation circuit, 6 is direction determination circuit, 7
Is an encoder, and 8 is a manually operated member.

In this structure, when the manual operation member 8 is rotated,
A two-phase pulse is output from the encoder 7 in time series according to the rotation angle and sent to the direction discriminator 6.

The direction discriminator 6 detects the rotation direction of the manually operated member 8 from the received two-phase pulse, gives a signal indicating the driving direction of the motor 3 to the drive circuit 4, and combines the two-phase pulse into a single-phase pulse. The single-phase pulse is applied to the constant width pulse generation circuit 5.

The constant-width pulse generation circuit 5 triggers the pulse edge of the single-phase pulse signal received from the direction discriminator 6 to activate the timer circuit, and gives the drive circuit 4 a drive signal of a constant width.

The drive circuit 4 energizes the motor 3 with the drive signal received from the constant width pulse generation circuit 5 in the direction designated by the direction discriminator 6 during the period of this drive signal.

FIG. 2 is a circuit diagram showing an electric circuit configuration of the block diagram shown in FIG. 1. Corresponding parts are designated by the same reference numerals.

FIG. 3 is a diagram showing the configuration of the encoder 7 of FIG. 1, and the corresponding parts are given the same numbers.

In FIG. 3, reference numerals 9 and 10 denote encoders 7.
Brush for two-phase signal generation, 75 is a ground brush,
76 is a conductive pattern.

Since the structure of the encoder 7 is a known technique, its detailed description is omitted.

With this structure, when the manual operation member 8 is rotated, the brush 9 and the brush 10 are alternately turned to the ground brush 75.
A two-phase signal is generated by switching to.

In FIG. 2, reference numeral 11 denotes a direction determining circuit of the direction discriminator 6, which receives two-phase signals from the brushes 9 and 10 and either one of the signal lines 12 and 13 depending on the rotating direction of the manual operation member 8. Becomes H level.

Reference numeral 14 denotes an XOR circuit for pulse synthesis, which is 2
The signal lines 15 and 16 of the two switches 9 and 10 are combined, the two-phase pulse is converted into a single-phase pulse, and the output signal line 17
A single-phase pulse is given to the constant-width pulse generation circuit 5 through.

The constant width pulse generation circuit 5 is an XOR circuit 14
The rising edge of the single-phase pulse, which is the output of, is used as a trigger, and then the output signal line 18
To H level.

When the next monophasic pulse arrives during this Δtl, the edge of the pulse is used as a trigger to re-enter Δt.
l is taken.

That is, assuming that the single-phase pulse interval is Δtp, if Δtp> Δtl (1), a pulse of Δtl width is generated from the constant width pulse generation circuit 5 for each Δtp, and Δtp ≦ Δtl (2) If so, the output of the constant-width pulse generation circuit 5 is kept at the H level until the period of the single-phase pulse satisfies the relation of the expression (1).

Reference numerals 19 and 20 denote AND circuits, which are driver transistors 23 and 24 for driving the motor 3 by synthesizing the output signal 18 of the constant width pulse generating circuit 5 and the output signals 12 to 13 of the direction determining circuit 11. , 25 and 26 are supplied with drive signals through signal lines 21 and 22.

FIG. 4 is a time chart showing the above-mentioned signal lines, the effective voltage 27 applied to the motor, and the speed 28 of the motor 3.

As is apparent from FIG. 4, when the manual operation member 8 rotates slowly, Δtp increases, the effective voltage 27 applied to the motor 3 decreases, the speed 28 of the motor 3 decreases, and inevitably. It is in a fine adjustment state.

When the manual operation member 8 rotates rapidly, Δtp decreases, the effective voltage 27 applied to the motor 3 increases, and the speed 28 of the motor 3 increases. At this time, of course, the coarse adjustment state is set.

That is, the present invention makes it possible to apply a pseudo PWM drive to the motor by directly performing pulse-energization time conversion from the single-phase pulse shown in FIG. 4 to generate a motor energization signal. .

According to this configuration, in changing the drive speed and drive amount of the motor according to the rotation speed of the manual operation member 8, the following advantages can be obtained as compared with the prior art.

(1) The rotation speed detecting means of the manually operated member is unnecessary.

(2) A PWM circuit for controlling the speed of the motor, a D / A converter circuit, etc. are unnecessary.

(3) Since the open loop control without the feedback control of the motor speed is possible, the encoder is unnecessary on the motor side.

<Second Embodiment> FIG. 5 is a block diagram showing a second embodiment of the present invention.

The present embodiment is an example in which the present invention is applied to control of a stepping motor.

In FIG. 5, 29 is an optical system, 30 is a moving lens group, 31 is a stepping motor for driving the moving lens group 30, 32 is a drive circuit, 33 is a v-f converter, 3
Reference numeral 4 is a constant width pulse generation circuit, 35 is a direction discriminator, 37 is a manual operation member, 36 is an encoder linked with the manual operation member 37, and 38 is a capacitor.

Signal lines 39 to 44 connect the blocks.

In this structure, when the manual operation member 37 is rotated, two-phase pulses are output in time series from the encoder 36 which is interlocked with the manual operation member 37 according to the rotation angle.
It is sent to the direction discriminator 35 through a signal line 39.

The direction discriminator 35 detects the rotation direction of the manually operated member 35 from the received two-phase pulse, and the drive circuit 32
A signal indicating the driving direction of the motor is applied to the signal line 41 through the signal line 41, and the two-phase pulse is combined into a single-phase pulse and applied to the constant width pulse generation circuit 34 through the signal line 40.

The constant-width pulse generation circuit 34 triggers the pulse edge of the single-phase pulse signal received from the direction discriminator 35 to generate a constant-width pulse signal to generate the signal line 4
Place on 2.

Here, the signal line 42 has a capacitor 3
8 are arranged in parallel, the waveform of the constant width pulse signal output from the constant width pulse generation circuit is blunted by the capacitance of the capacitor 38, and becomes a substantially effective voltage 42a. This signal, which has been converted to a substantially effective voltage, is input to the v-f converter 33.

The v-f converter 33 has the substantially effective voltage 42.
The voltage of a is converted from frequency to frequency, which is given to the drive circuit 32 through the signal line 43 as a frequency for driving the stepping motor.

The drive circuit 32 is a stepping motor 31.
In response to the frequency signal given by the v-f converter 33, a drive signal is given in the direction indicated by the direction discriminator 35.

As a result, the stepping motor 31 is driven and the moving lens group 30 moves in the optical axis direction.

FIG. 6 is a time chart showing the signal lines and the motor speed 45.

As shown in FIG. 6, according to this configuration, when the rotation speed of the manual operation member 37 is slow, the effective voltage becomes low, so that the output frequency of the v-f converter 33 also becomes low and the motor. The rotation speed of is slow and the amount of drive per unit time is also small.

Further, when the rotation speed of the manual operation member 37 is high, the effective voltage increases, so that the output frequency of the v-f converter 33 also increases and the rotation speed of the motor increases and the drive amount per unit time also increases.

According to this configuration, in changing the speed of the stepping motor 31 according to the rotation speed of the manual operation member 37, the following advantages can be obtained as compared with the conventional case.

(1) The rotation speed detecting means of the manually operated member is unnecessary.

(2) The reference voltage for controlling the speed of the stepping motor can be obtained with a simple structure, and the cost of the device can be reduced.

<Third Embodiment> FIG. 7 is a block diagram showing a third embodiment of the present invention.

In this embodiment, the direction discriminating means and the constant width pulse generating means are realized by the control of the microcomputer, and D
This is an example applied to control of a C motor.

In FIG. 7, 46 is an optical system, 47 is a moving lens group, 48 is a DC motor for driving the moving lens group 47, 49 is a drive circuit for the motor 48, 50 is an I / O port, and 51 is a micro. The CPU of the computer, 52 is a memory, 53 is a timer, 54 is an I / O port, 55 is an encoder, and 56 is a manual operation member.

FIG. 8 is a schematic flowchart of the main program for operating the microcomputer in this embodiment.

FIG. 9 is a schematic flowchart of an interrupt routine for performing a timer interrupt process for setting a constant width Δt of a constant width pulse signal.

Next, the operation of this embodiment will be described with reference to the flow charts of FIGS.

First, after the power is turned on, the process proceeds to step 101.

(Step 101) I / O ports 50, 5
4 is initialized and I / O port 54 is used as an input port and I / O.
Set port 50 as the output port.

Thereafter, the energization stop data is output to the I / O port 50, and the energization stop command is sent to the drive circuit 49.

The drive circuit 49 which has received the energization stop command stops energizing the motor 48, and the motor 48 is turned off.

(Step 102) RAM in the memory 52
Inside, as a work area for passing data to the interrupt routine described later, the counter and direc
secure the tion.

The meaning of each work area is as follows.

Counter: Stores the count value of the encoder.

Direction: The rotation direction of the encoder is stored.

(Step 103) The interrupt period of the interval timer 53 is set to Δt, and the interrupt address is set to the interrupt routine described later.

After that, the interrupt is permitted.

(Step 104) The output of the encoder 55 is fetched into the CPU 51 via the I / O port 54.
(Step 105) The data read in Step 104 is judged, and if no new pulse is generated, the process returns to Step 104.

(Step 106) The rotation direction of the manually operated member is determined from the data read in Step 104, and this rotation direction and the dir stored in the work area are determined.
Compare the data of the action.

That is, it is determined whether the rotation is in the same direction as the previous rotation.

As a result of the judgment, if the direction is the same as the previous time, the process proceeds to step 107, and if it is the reverse direction to the previous time, the process proceeds to step.

(Step 107) Disable interrupts.

The value of counter in the work area is read, the process of counter ← counter + 1 is performed, and the value of counter is stored in the work area again.

Enable interrupts.

Control is transferred to step 104.

(Step 108) Disable interrupts.

"1" in the counter in the work area
Write.

(Step 109) di in the work area
The direction value is read, the process of direction ← not (direction) is performed, the direction is reversed, and the work area is di
Store the value of "redirection".

Enable interrupts.

Control is passed to step 104.

After that, from step 104 to step 109
Repeat the above operations.

By the operation of steps 101 to 109 described above, the output of the encoder 55, that is, the rotation of the manual operation member 56 is captured and stored in the two values of the work area, counter and direction.

Next, this counter and direct
The operation of the interrupt processing routine that operates by receiving the value of ion will be described.

The interrupt processing routine is activated every Δt during the period in which interrupts are enabled in the loop of steps 104 to 109 described above.

A flowchart of the interrupt processing routine is shown in FIG. 9. When an interrupt occurs, the control shifts to 110.

(Step 110) When the interrupt processing routine is activated, first, various flags and registers are saved in the stack.

(Step 111) co in the work area
Get the unter value and check if it is 0 or not.

If it is 0, the control is transferred to step 116, and if it is not 0, the process proceeds to step 112.

(Step 112) dir of work area
The value of section is acquired and it is determined whether it is normal rotation or reverse rotation.

At this time, if it is normal rotation, the control shifts to step 113, and if it is reverse rotation, control shifts to step 115.

(Step 113) Forward rotation energization data is output to the I / O port 50.

When the forward rotation energization data is output to the I / O port 50, the forward rotation energization command is given to the drive circuit 49.

Drive circuit 49 which has received the forward rotation energization command
Energizes the motor 48 in the forward direction.

As a result, the motor 48 rotates in the forward direction and drives the moving lens group 47 in the forward direction.

(Step 114) co in the work area
The value of counter is read, the processing of counter ← counter-1 is performed, and the value of counter is stored in the work area again.

Control is transferred to step 117.

(Step 115) Reverse rotation energization data is output to the I / O port 50.

When the reverse rotation energization data is output to the I / O port 50, the reverse rotation energization command is given to the drive circuit 49.

Drive circuit 49 which has received the reverse rotation energization command
Energizes the motor 48 in the reverse direction.

As a result, the motor 48 rotates in the reverse direction and drives the moving lens group 47 in the reverse direction.

Thereafter, the control shifts to step 114.

(Step 116) The energization stop data is output to the I / O port 50.

When the energization stop data is output to the I / O port 50, an energization stop command is given to the drive circuit 49.

The drive circuit 49 which has received the energization stop command
Stops the power supply to the motor 48, and the motor 48 is turned off.

(Step 117) Various flags and registers saved in the stack are restored, and control is returned to the original routine of the interrupt.

The interrupt routine is composed of steps 110 to 117 described above, and is executed every Δt.

FIG. 10 is a time chart of this embodiment.

In FIG. 10, reference numeral 58 is an encoder signal, 77 is a direction instruction signal given to the drive circuit 49, and 5 is a direction instruction signal.
9 is a motor drive signal given to the drive circuit 49, 60
Is the effective voltage applied to the motor 48, 61 is the motor 48
Represents the speed of.

As can be seen by comparing FIG. 10 with FIG. 4 in the first embodiment, also in this embodiment, except that the trigger position of Δt of the motor drive signal is delayed by the maximum Δt. The same operation as is performed.

According to this structure, in changing the speed of the motor 48 according to the rotation speed of the manual operation member 56, the following advantages can be obtained as compared with the conventional one.

(1) The rotation speed detecting means of the manually operated member is unnecessary.

(2) The PWM circuit for controlling the speed of the motor, the D / A converter circuit, etc. are unnecessary.

(3) Since the open loop control without the feedback control of the motor speed is possible, the encoder is not required on the motor side.

<Fourth Embodiment> FIG. 11 is a block diagram showing a fourth embodiment of the present invention.

The present embodiment is an example in which the present invention is applied to control of an ultrasonic motor (hereinafter abbreviated as USM).

In FIG. 11, 62 is an optical system, 63 is a moving lens group, 64 is a USM for driving the moving lens group 63,
65 is a drive circuit of USM64, 66 is an I / O port, 6
7 is a microcomputer, 68 is an I / O port, 69
Is an A / D converter connected to the I / O port 68, 70 is a capacitor, 71 is a constant width pulse generation circuit,
Reference numeral 72 is a direction discriminator, 74 is a manual operation member, and 73 is an encoder interlocked with the manual operation member 74.

In this structure, when the manual operation member 74 is operated, the encoder 73 interlocked with the manual operation member 74 outputs a two-phase pulse corresponding to the rotation angle of the manual operation member 74.

The two-phase pulse output from the encoder 73 is sent to the direction discriminator 72.

The direction discriminator 72 synthesizes the received two-phase pulse into a single-phase pulse and sends it to the constant-width pulse generation circuit 71, and at the same time detects the rotation direction of the manually operated member 74 from the two-phase pulse and outputs the direction indication data. Send to I / O port 68.

The constant width pulse generation circuit 71 which receives the single phase pulse generates a constant width pulse signal by using the edge of the single phase pulse as a trigger.

The constant width pulse signal generated here is A / D
It is sent to the converter 69.

Since the capacitor 70 is arranged in parallel in the signal line for sending this signal to the A / D converter 69, the constant width pulse signal output from the constant width pulse generating circuit has a waveform depending on the capacity of the capacitor 70. The rounding is applied to the A / D converter 69 as a substantially effective voltage.

The A / D converter 69 converts this substantially effective voltage from analog to digital, converts it into digital data, and outputs it as I data.
/ O port 68.

The above-mentioned two types of data, that is, the direction designating data and the digital data after A / D conversion, are input to the I / O port 68.

The microcomputer 67 associates the above two kinds of data of the I / O port 68 with each other in the following manner and uses the USM.
64 is controlled.

-Direction designation data-> USM64 drive direction -Digital data after A / D conversion-> USM64 drive speed The method by which the microcomputer 67 controls the USM64 is a well-known technique, and therefore its explanation is omitted.

Also in the above-mentioned configuration, the first to third
A feeling of operation similar to that of the embodiment can be obtained.

The present invention is not limited to the control of the motor described above, but can be applied to the control of various motors such as a linear type motor.

Needless to say, the encoder for detecting the rotation of the manually operated member may be any of various encoders such as mechanical type, magnetic type and optical type.

In the above-described embodiments, the present invention is applied only to optical devices such as cameras, but the technique of the present invention can be applied to general power manipulating devices (for example, magic hand and remote control device). Clearly applicable.

[0136]

As described above, according to the present invention, the following effects can be obtained.

(1) The driving speed of the motor is arbitrarily changed according to the rotation speed of the operating member, and an operation feeling that matches the sensitivity of the operator can be obtained.

(2) The drive amount of the motor is arbitrarily changed according to the rotation speed of the operating member, and it is not necessary to switch between coarse adjustment and fine adjustment.

(3) Since it is not necessary to detect the rotation speed of the operating member, a dedicated circuit such as an fv converter or a timer for measuring the interval is unnecessary, so that the cost of the device can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment of a power manipulating type lens driving device configured by applying the present invention.

FIG. 2 is a circuit diagram of an electronic control system having the configuration shown in FIG.

FIG. 3 is a configuration diagram of an encoder 7 used in the configuration of FIG.

FIG. 4 is a time chart of signals of respective parts in the configurations of FIGS. 1 and 2.

FIG. 5 is a block diagram of a second embodiment of a lens driving device to which the present invention has been applied.

FIG. 6 is a time chart of signals of various parts in the configuration of FIG.

FIG. 7 is a block diagram of a third embodiment of a lens driving device to which the present invention has been applied.

FIG. 8 is a schematic flowchart of a main program of control operation of the third embodiment.

FIG. 9 is a schematic flowchart of an interrupt routine of control operation of the third embodiment.

FIG. 10 is a time chart of signals at various parts in the third embodiment shown in FIG.

FIG. 11 is a block diagram of a lens driving device according to a fourth embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical system 2 ... Moving lens group 3 ... Motor 4 ... Drive circuit 5 ... Constant width pulse generation circuit 6 ... Direction discriminator 7 ... Encoder 8 ... Manual operation member 9, 10 ... Brush 11 ... Direction discrimination circuit 12, 13 ... Signal line 14 ... XOR circuit 15, 16, 17, 18 ... Signal line 19, 20 ... AN
D circuit 21, 22 ... Signal line 23, 24, 25, 26 ... Driver transistor 27 ... Effective voltage 28 ... Motor 3
Speed 29 ... Optical system 30 ... Moving lens group 31 ... Stepping motor 32 ... Drive circuit 33 ... Vf converter 34 ... Constant width pulse generation circuit 35 ... Direction discriminator 36 ... Encoder 37 ... Manual operation member 38 ... Capacitor 39 , 40, 41, 42, 43, 44 ... Signal line 42a ... Substantially effective voltage 45 ... Motor 3
1 speed 46 ... Optical system 47 ... Moving lens group 48 ... DC motor 49 ... Drive circuit 50 ... I / O port 51 ... CPU 52 ... Memory 53 ... Timer 54 ... I / O port 55 ... Encoder 56 ... Manual operation member 58 Encoder signal 59 Motor drive signal given to drive circuit 60 Effective voltage applied to motor 48 61 Speed of motor 62 62 Optical system 63 Moving lens group 64 USM 65 Drive circuit 66 I / O port 67 ... Microcomputer 68 ... I / O port 69 ... A / D converter 70 ... Capacitor 71 ... Constant width pulse generation circuit 72 ... Direction discriminator 73 ... Encoder 74 ... Manual operation member 75 ... Grand brush 76 ... Conductive pattern 77 ... Direction Instruction signal

Claims (6)

[Claims] 1. A manual operation member that is rotated by hand, a drive source that drives a driven object member, and pulse generation means that interlocks with the rotation of the manual operation member and generates a pulse signal according to a rotation angle. A constant width pulse signal generating means for generating a constant width pulse signal in response to the generation of the pulse signal, a direction discriminating means for detecting the rotation direction of the manually operated member from the pulse signal, and a drive source for controlling the drive source. And a control means,
An object driving apparatus characterized in that the drive source control means is controlled by the constant width pulse signal and the output of the direction determining means. 2. The drive source is a DC motor, and the drive source control means has a function of energizing the DC motor in the direction detected by the direction determining means during the pulse width of the constant width pulse signal. Claim 1 characterized by having.
Object drive device. 3. The drive source is a stepping motor, the drive source control means converts the constant width pulse signal into an analog effective voltage, and the analog effective voltage is v-
v-f converting means for f-converting, and has a function of giving a drive signal to the stepping motor according to the frequency obtained by the v-f converting means and the direction detected by the direction determining means. The object drive device according to claim 1, wherein the object drive device is a device. 4. The driving means includes a microcomputer, and means for converting the constant width pulse signal into an analog effective voltage, and means for A / D converting the unlogged effective voltage.
And having a function of fetching a digitally converted output into the microcomputer and controlling the drive source according to the digital output and the direction detected by the direction determining means. The object drive device according to claim 1. 5. The drive source is an ultrasonic motor, the drive source control means includes a microcomputer, and means for converting the constant width pulse signal into an analog effective voltage, and A / D conversion of the analog effective voltage. And a function for determining the driving speed of the ultrasonic motor based on the digital output and the direction detected by the direction determining means. The object drive device according to claim 1, wherein the object drive device is provided. 6. The object to be driven is at least one lens group of an optical system of an optical device, and the object driving device constitutes a power manipulating device for driving a lens of the optical device. The object drive device according to claim 1.