JP2006223077A - Drive device of ultrasonic vibrator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive device of an ultrasonic vibrator that can drive a plurality of the ultrasonic vibrators by one unit. <P>SOLUTION: The drive device of the ultrasonic vibrator includes an ultrasonic vibrator selector 11 that selects the ultrasonic vibrator 25 of an X-axis ultrasonic motor 21 from the ultrasonic vibrators 25, 26 attached to a plurality of the ultrasonic motors 21, 22 as the selected ultrasonic vibrator, a drive signal generator 12 that generates a drive signal to the ultrasonic vibrator 25, a drive power generator 13 that generates drive power by amplifying the drive signal in terms of power; and a connector 14 that electrically connects the drive power generator 13 and the ultrasonic vibrator 25. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ultrasonic transducer driving device, and more particularly to an ultrasonic transducer driving device capable of driving a plurality of ultrasonic transducers.

  An ultrasonic motor using an ultrasonic transducer as a driving source has been applied as a driving device for a moving body that needs to move a minute distance accurately like a microscope stage.

  The present applicant has already proposed an ultrasonic motor driving device capable of controlling the displacement and speed very precisely (see, for example, Patent Document 1).

  FIG. 6 is a block diagram of an ultrasonic motor driving apparatus already proposed by the present applicant. The X / Y stage 91 is driven by an ultrasonic motor 92 arranged in contact with the X / Y stage 91.

  The ultrasonic motor drive device 9 includes a control unit 93 that outputs a command signal, a drive pattern determination board 94 that determines a drive pattern based on the command signal, and an ultrasonic wave attached to the ultrasonic motor 92 based on the drive pattern. And a drive signal substrate 95 that generates a drive signal for driving the vibrators 96 and 97.

  The controller 93 outputs the displacement target value and the speed target value, and the drive pattern determination board 94 determines a drive pattern that is a sine wave having a wave number determined according to the displacement target value with an interval determined according to the speed target value interposed therebetween. .

  The drive signal board 95 generates a drive signal having a frequency and amplitude instructed from the control unit 93 based on the drive pattern, and excites the ultrasonic transducers 96 and 97 of the ultrasonic motor 92.

  The ultrasonic motor driving apparatus according to the above proposal drives a single ultrasonic motor. When driving a multi-axis stage with an ultrasonic motor, several ultrasonic motor driving apparatuses are required. Become.

  In addition, an ultrasonic motor drive system that can drive a plurality of ultrasonic motors with a single control circuit has already been proposed (see, for example, Patent Document 2).

The ultrasonic motor drive system according to the above proposal generates an operation command for a plurality of ultrasonic motors with a single control circuit, and a driver for driving the ultrasonic motor based on the operation command is installed for each ultrasonic motor. There is a need to.
JP 2004-201405 A ([0018] to [0021], FIG. 1) JP 2003-284367 A ([0012], FIG. 1)

  However, in an XY stage having a plurality of ultrasonic motors, there are not only a few cases where a plurality of ultrasonic motors are operated at the same time, and even when power is not supplied to the ultrasonic motors, Since the X / Y stage can maintain the current position by the mechanical frictional force acting between the Y stage and the ultrasonic vibrator driving device or driver for each ultrasonic vibrator of the ultrasonic motor. The installation not only increases the size of the drive device but also deteriorates the economy.

  In order to solve the conventional problems, an object of the present invention is to provide an ultrasonic transducer driving apparatus having a simple configuration capable of driving a plurality of ultrasonic transducers.

  An ultrasonic transducer driving device according to the present invention is an ultrasonic transducer driving device that supplies driving power to a plurality of ultrasonic transducers, and includes one ultrasonic transducer among the plurality of ultrasonic transducers. An ultrasonic transducer selection unit that is selected as a selected ultrasonic transducer, a drive signal generation unit that generates a drive signal for the selected ultrasonic transducer, and a drive power generator that generates drive power by amplifying the drive signal And a connection unit that electrically connects the drive power generation unit and the selected ultrasonic transducer.

  With this configuration, a plurality of ultrasonic transducers can be driven by one ultrasonic transducer driving device.

  In the ultrasonic transducer driving apparatus of the present invention, the ultrasonic transducer selection unit drives a driven body, which is driven by the selected ultrasonic transducer, by a predetermined drive amount. Is detected, a first selection change unit that changes the selection of the plurality of ultrasonic transducers is included.

  With this configuration, it is possible to change the ultrasonic transducer to be driven every time the operation of one ultrasonic transducer is completed, and to drive a plurality of ultrasonic transducers by one ultrasonic transducer driving device. It becomes.

  In the ultrasonic transducer driving device of the present invention, after the ultrasonic transducer selecting unit drives the driven body driven by the selected ultrasonic transducer by the selected ultrasonic transducer for a predetermined time, It has the structure including the 2nd selection change part which changes selection of the said some ultrasonic transducer | vibrator.

  With this configuration, a plurality of ultrasonic transducers can be driven by a single ultrasonic transducer driving device by changing the ultrasonic transducer to be driven every predetermined time.

  The ultrasonic transducer driving apparatus according to the present invention includes a measuring unit that measures the amount of movement of the driven body by the selected ultrasonic transducer, and the ultrasonic transducer selecting unit that measures the amount of movement measured by the measuring unit. It has a configuration including feedback on / off means for turning on / off the feedback.

  With this configuration, the operation amount of the driven body can be controlled by feed forward control or feedback control.

  The present invention electrically connects an ultrasonic transducer selecting unit that selects one ultrasonic transducer as a selected ultrasonic transducer from among a plurality of ultrasonic transducers, a drive power generation unit, and a selected ultrasonic transducer. By providing the connection portion connected to the ultrasonic transducer driving device, it is possible to provide an ultrasonic transducer driving device having an effect that a plurality of ultrasonic transducers can be driven by one unit.

  Hereinafter, an ultrasonic transducer driving apparatus according to an embodiment of the present invention will be described with reference to the drawings.

  In the embodiment, it is assumed that the ultrasonic transducer is attached to an ultrasonic motor and drives the XY stage.

  As shown in the block diagram of FIG. 1, the ultrasonic transducer driving apparatus 1 according to the embodiment of the present invention includes an X-axis from among ultrasonic transducers 25 and 26 attached to a plurality of ultrasonic motors 21 and 22. An ultrasonic transducer selection unit 11 that selects the ultrasonic transducer 25 attached to the ultrasonic motor 21 as a selected ultrasonic transducer, and a drive signal for the ultrasonic transducer 25 attached to the X-axis ultrasonic motor 21. A drive signal generation unit 12 to generate, a drive power generation unit 13 that amplifies the drive signal to generate drive power, an ultrasonic transducer 25 attached to the drive power generation unit 13 and the X-axis ultrasonic motor 21; And a connecting portion 14 for electrically connecting the two.

  An X-axis direction movement amount measuring device 23 that measures the X-axis direction movement amount of the X / Y stage, a Y-axis direction movement amount measuring device 24 that measures the Y-axis direction movement amount, and the ultrasonic transducer selecting unit 11. May be provided with a switching unit 15 for switching the measurement result of the X-axis direction movement amount measuring device 23 or the Y-axis direction movement amount measuring device 24 input to the.

  FIG. 2 is a block diagram showing a hardware configuration of the ultrasonic transducer driving apparatus 1 according to the embodiment of the present invention. The ultrasonic transducer selecting unit 11 and the drive signal generating unit 12 are included in the microcomputer 4. Configured in software.

  The microcomputer 4 includes a CPU 41 that executes a program installed in the microcomputer 4, a memory 42 that stores the program and calculation results, and an operation panel interface (hereinafter referred to as “I / F”) to which the operation panel 5 is connected. 43, a drive signal I / F 44 that outputs a drive signal for the ultrasonic motor, an identification signal I / F 45 that outputs an identification signal to the connection unit 14, and a feedback signal input I / F 46 that inputs a feedback signal. It has the structure connected to.

  The operation panel 5 connected to the operation panel I / F 43 includes a liquid crystal display panel 51, a pointing device 52, and a data input key 53.

  The drive signal I / F 44 supplies a drive signal to the driver 55. The driver 55 amplifies the supplied drive signal to generate drive power. The driver 55 functions as the drive signal generation unit 12.

  The identification signal output circuit 57 connected to the identification signal I / F 45 operates the relay 58 and the relay 59 based on the identification signal output from the identification signal I / F 45.

  The relay 58 and the relay 59 are controlled so that the contact is in the contact state when the identification signal is on, and the contact is disconnected when the identification signal is off.

  The identification signal output circuit 57 and the relays 58 and 59 function as the connection unit 14.

  The feedback signal input I / F 46 feeds back a detection signal of the position of the X / Y table 2 in the X-axis direction and the Y-axis direction.

  The X / Y table 2 supplies the driving power output by the driver 55 to the ultrasonic transducer 25 of the X-axis ultrasonic motor 21 to supply the ultrasonic transducer 26 of the Y-axis ultrasonic motor 22 in the X-axis direction. It is configured to be movable in the Y-axis direction by supplying driving power output from the driver 55.

  The X-axis direction moving amount measuring device (for example, linear encoder) 23 detects the X-axis direction position of the X / Y table 2, and the Y-axis direction moving amount measuring device (for example, linear encoder) 24 is used for the X / Y table. 2 is detected, and the X and Y position of the XY table 2 is fed back to the drive signal generator 12 via the feedback signal input I / F 46.

  In the feedback path, a relay 60 and a relay 61 that connect and disconnect the feedback signal are installed and driven by the identification signal output circuit 57. The relay 60 and the relay 61 function as the switching unit 15.

  The ultrasonic transducer 25 of the X-axis ultrasonic motor 21 and the ultrasonic transducer 26 of the Y-axis ultrasonic motor 22 are driven by driving power output from the driver 55, respectively.

  The driver 55 and the ultrasonic transducer 25 of the X-axis ultrasonic motor 21 and the ultrasonic transducer 26 of the Y-axis ultrasonic motor 22 are connected via a relay 58 and a relay 59.

  That is, when the identification signal output circuit 57 outputs an ON signal to the relay 58, the contact of the relay 58 is closed and the relay 59 is opened, and the driving power output from the driver 55 is the ultrasonic vibration of the X-axis ultrasonic motor 21. The driving power supplied to the ultrasonic transducer 26 of the Y-axis ultrasonic motor 22 is supplied to the child 25 and cut off.

  When the identification signal output circuit 57 outputs an ON signal to the relay 58, the relay 60 of the feedback path is opened and the relay 61 is closed, and the measurement result by the X-axis direction movement measuring device 23 is the feedback signal input I / F 46. It is comprised so that it may be input.

  When the identification signal output circuit 57 outputs an ON signal to the relay 59, the contact of the relay 59 is closed and the relay 58 is opened, and the driving power output from the driver 55 is the ultrasonic vibration of the Y-axis ultrasonic motor 22. The driving power supplied to the child 26 and to the ultrasonic transducer 25 of the X-axis ultrasonic motor 21 is cut off.

  When the identification signal output circuit 57 outputs an ON signal to the relay 59, the relay 61 in the feedback path is in the open state and the relay 60 is in the closed state, and the measurement result by the Y-axis direction movement measuring device 24 is the feedback signal input I / F 46. It is comprised so that it may be input.

  In the above embodiment, the connecting portion 14 is constituted by the relay 58 and the relay 59, but a semiconductor switching element may be used instead of the relay.

  Since the semiconductor switching element is smaller than the relay, it can be installed on the substrate of the driver 55.

Two examples of the operation of the ultrasonic transducer driving device according to the present invention will be described below.
(First embodiment)
FIG. 3 is a flowchart of a first ultrasonic transducer driving routine installed in the microcomputer 4, and driving of another ultrasonic transducer is started after the operation of one ultrasonic transducer is completed. .

  First, the CPU 41 initializes the identification index i of the plurality of ultrasonic transducers to be driven to “1” (step S31).

  Next, the CPU 41 outputs the identification index i of the ultrasonic transducer to the identification signal output circuit 57 via the identification signal I / F 45 (step S32). In the present embodiment, when the identification index i of the ultrasonic transducer is “1”, the relay 58 is closed and the relay 59 is opened, and the driving power output from the driver 55 is the X-axis ultrasonic motor 21. To the ultrasonic transducer 25.

  The driving power is not supplied to the ultrasonic transducer 26 of the Y-axis ultrasonic motor 22, but the stator and rotor of the Y-axis ultrasonic motor 22 are kept in contact with each other. The movement of the Y table 2 in the Y-axis direction is prevented.

  Next, the CPU 41 reads the target position Pd (1) in the X-axis direction of the driven body (step S33). The target position Pd (1) may be read from the operation panel 5 or may be read from a host control device (not shown).

  The CPU 41 generates a drive signal having a wave number determined based on the target position Pd (1) (step S34), and outputs the drive signal to the driver 55 via the drive signal I / F 44 (step S35).

  The CPU 41 reads the actual position Pa (1) in the X-axis direction of the XY table 2 measured by the X-axis direction movement measuring device 23 via the feedback signal input I / F 46 (step S36), and the X-axis direction. It is determined whether or not the absolute value of the difference between the target position Pd (1) and the actual position Pa (1) is less than a predetermined error ε (step S37).

  If the absolute value of the difference is equal to or larger than the error ε, the CPU 41 returns to step S34 on the assumption that the XY table 2 has not reached the target position Pd (1) in the X-axis direction, and continues to generate the drive signal. .

  If the absolute value of the difference is less than the error ε, the CPU 41 determines whether or not the ultrasonic transducer identification index i is greater than or equal to the number I of ultrasonic transducers to be driven (step S38).

  In the present embodiment, the ultrasonic transducer driving apparatus of the present invention drives the ultrasonic transducer 25 of the X-axis ultrasonic motor 21 of the X / Y table 2 and the ultrasonic transducer 26 of the Y-axis ultrasonic motor 22. Therefore, a negative determination is made in step S38, the identification index i of the ultrasonic transducer is incremented to “2” (step S39), and the process returns to step S32.

  The CPU 41 outputs the identification index i of the ultrasonic transducer to the identification signal output circuit 57 via the identification signal I / F 45 (step S32). When the identification index i of the ultrasonic transducer is “2”, The relay 58 is opened and the relay 59 is closed, and the driving power output from the driver 55 is supplied to the ultrasonic transducer 26 of the Y-axis ultrasonic motor 22.

  Driving power is not supplied to the ultrasonic transducer 25 of the X-axis ultrasonic motor 21, but the stator and the rotor of the X-axis ultrasonic motor 21 are kept in contact with each other. Directional movement is prevented.

  The CPU 41 reads the target position Pd (2) of the driven body in the Y-axis direction (step S33).

  The CPU 41 generates a drive signal having a wave number determined based on the target position Pd (2) (step S34), and outputs the drive signal to the driver 55 via the drive signal I / F 44 (step S35).

  The CPU 41 reads the actual position Pa (2) in the Y-axis direction of the XY table 2 measured by the Y-axis direction movement measuring device 24 via the feedback signal input I / F 46 (step S36), and the Y-axis direction. It is determined whether or not the absolute value of the difference between the target position Pd (2) and the actual position Pa (2) is less than a predetermined error ε (step S37).

  If the absolute value of the difference is equal to or larger than the error ε, the CPU 41 returns to step S34 on the assumption that the XY table 2 has not reached the target position Pd (2) in the Y-axis direction, and continues to generate the drive signal. .

  If the absolute value of the difference is less than the error ε, the CPU 41 determines whether or not the ultrasonic transducer identification index i is greater than or equal to the number I of ultrasonic transducers to be driven (step S38).

  Since the identification index i of the ultrasonic transducer is “2”, an affirmative determination is made in step S38, and this routine is terminated.

  In the first embodiment, the X-axis direction position and the Y-axis direction position of the XY table 2 are measured by the X-axis direction movement amount measuring device 23 and the Y-axis direction movement amount measuring device 24. However, the X-axis direction target position and the Y-axis direction target position may be detected by a position detection switch.

  That is, position detection switches such as photosensors and microswitches are installed at the X-axis direction target position and the Y-axis direction target position of the X / Y table 2, and the state of the position detection switch is read in step S36. When X is reversed, it may be determined that the XY table 2 has reached the target position.

  Further, the ultrasonic transducer is turned on each time the drive signal generator 12 outputs a predetermined number of pulses without using the feedback from the X-axis direction movement measuring device 23 and the Y-axis direction movement measuring device 24. You may make it switch.

As described above, according to the first embodiment, a plurality of ultrasonic transducers are driven by one ultrasonic transducer driving device by changing the ultrasonic transducer to be driven every time the operation of one ultrasonic transducer is completed. It becomes possible to drive the ultrasonic transducer of the table.
(Second embodiment)
FIGS. 4 and 5 are flowcharts of the identification index switching routine and the second ultrasonic transducer driving routine installed in the microcomputer 4, and are super-driven for every predetermined time (for example, 1 second). The sound wave oscillator is switched.

  FIG. 4 is a flowchart of the identification index switching routine of the ultrasonic transducer, which is executed at predetermined time intervals.

  First, the CPU 41 determines whether or not the identification index i is greater than or equal to the maximum value I (step S41).

  The CPU 41 initializes the identification index i to “1” when it is determined that the identification index i reaches the maximum value I (step S42), and increments the identification index i when it is determined that the identification index i is less than the maximum value I. (Step S43).

  Finally, the CPU 41 outputs the identification index i to the identification signal output circuit 57 via the identification signal I / F 45 (step S44).

  FIG. 5 is a flowchart of the second ultrasonic transducer driving routine, which is executed every 100 milliseconds, for example.

  The CPU 41 first reads the identification index i output from the identification index switching routine (step S51). Next, the CPU 41 reads the target position Pd (i) from the operation panel 5 or the host control device (not shown) (step S52).

  The CPU 41 generates a drive signal based on the target position Pd (i) (step S53), and outputs it to the driver 55 via the drive signal I / F 44 (step S54).

  The position control or speed control of the XY table 2 is executed by a position control routine or speed control routine (not shown).

  As described above, according to the second embodiment, a plurality of ultrasonic transducers are driven by one ultrasonic transducer driving device by changing the ultrasonic transducer to be driven every predetermined time. It becomes possible.

  In the above embodiment, the movement amount of the X / Y table 2 is measured by the X-axis direction movement amount measuring device 23 and the Y-axis direction movement amount measuring device 24 and fed back to the ultrasonic transducer driving device 1. However, the feedback of the movement amount is not essential.

  That is, the XY table 2 may be driven by so-called open loop control in which both the relay 60 and the relay 61 are opened and the movement amount is not measured, or is strictly equivalent to the movement amount of the XY table. However, the XY table 2 may be driven by so-called semi-closed loop control that feeds back the number of pulses or the movement amount of the ultrasonic motor.

  As described above, the ultrasonic transducer driving device according to the present invention has an effect that a single ultrasonic transducer can be driven, and is effective as a driving device such as a piezoelectric element. .

Block diagram of an ultrasonic transducer driving apparatus according to an embodiment of the present invention 1 is a block diagram of a hardware configuration of an ultrasonic transducer driving apparatus according to an embodiment of the present invention. The flowchart of the 1st ultrasonic motor drive routine installed in the ultrasonic transducer drive device of embodiment concerning this invention Flowchart of identification index switching routine installed in the ultrasonic transducer driving apparatus according to the embodiment of the present invention Flowchart of a second ultrasonic motor driving routine installed in the ultrasonic transducer driving apparatus according to the embodiment of the present invention. Block diagram of a conventional ultrasonic motor drive device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic transducer drive device 2 X * Y table 11 Ultrasonic transducer selection part 12 Drive signal generation part 13 Drive power generation part 14 Connection part 21 X-axis ultrasonic motor 22 Y-axis ultrasonic motor 23 X-axis direction movement amount Measuring device 24 Y-axis direction movement measuring device 25, 26 Ultrasonic transducer

Claims (4)

An ultrasonic transducer driving apparatus that supplies driving power to a plurality of ultrasonic transducers,
An ultrasonic transducer selecting unit that selects one ultrasonic transducer as a selected ultrasonic transducer from the plurality of ultrasonic transducers;
A drive signal generator for generating a drive signal for the selected ultrasonic transducer;
A drive power generation unit that amplifies the drive signal to generate drive power;
An ultrasonic transducer driving apparatus including a connection unit that electrically connects the drive power generation unit and the selected ultrasonic transducer. After the ultrasonic transducer selection unit detects that the selected ultrasonic transducer has driven a driven body driven by the selected ultrasonic transducer with a predetermined drive amount, the plurality of ultrasonic waves The ultrasonic transducer driving apparatus according to claim 1, further comprising a first selection change unit that changes a selection of the transducer. The ultrasonic transducer selection unit changes the selection of the plurality of ultrasonic transducers after the driven ultrasonic transducer is driven by the selected ultrasonic transducer for a predetermined time. The ultrasonic transducer driving device according to claim 1, further comprising a second selection changing unit that performs the selection. Measuring means for measuring an operation amount of the driven body by the selected ultrasonic transducer;
4. The ultrasonic transducer driving apparatus according to claim 1, further comprising a feedback on / off unit configured to turn on / off feedback of the operation amount measured by the measurement unit to the ultrasonic transducer selection unit. 5.

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