A driving-unit operation method includes: generating pulse blocks on the basis of driving pulses; and modifying a driving signal in accordance with a position error signal. In the modifying the driving signal, when the position error signal is in a first range, the shape of the driving pulses is modified so as to form a first driving-pulse shape, and the pulse-block duty cycle is set to a first pulse-block duty cycle value, whereas when the position error signal is in a second range, the shape of the driving pulses is modified so as to form a second driving-pulse shape, and the pulse-block duty cycle is set to a second pulse-block duty cycle value.

A control method for a piezoelectric drive device includes a first step of executing first control to decrease a frequency of a drive voltage applied to a piezoelectric vibrator from a predetermined first frequency while acquiring a pickup voltage representing vibration amplitude of the piezoelectric vibrator, and a second step of executing second control to increase the frequency of the drive voltage applied to the piezoelectric vibrator to a second frequency as a frequency of the drive voltage applied before a second time when the pickup voltage is higher from a first time to the second time and the pickup voltage is lower from the second time to a third time.

A vibration actuator is capable of reducing differences in vibration phase and vibration amplitude without raising a voltage of a drive circuit when driving a contact member using a plurality of vibrators connected in series. The vibration actuator includes a vibrator device and a contact member that moves relative to the vibrator device. The vibrator device includes transformers of which primary coils are connected in series, and vibrators that are respectively connected in parallel to secondary coils of the transformers.

Disclosed herein is a microelectromechanical (MEMS) device, including a rotor and a first piezoelectric actuator mechanically coupled to the rotor. The first piezoelectric actuator is electrically coupled between a first signal node and a common voltage node. A second piezoelectric actuator is mechanically coupled to the rotor, and is electrically coupled between a second signal node and the common voltage node. Control circuitry includes a drive circuit configured to drive the first and second piezoelectric actuators, a sense circuit configured to process sense signals generated by the first and second pizeoelectric actuators, and a multiplexing circuit. The multiplexing circuit is configured to alternate between connecting the drive circuit to the first piezoelectric actuator while connecting the sense circuit to the second piezoelectric actuator, and connecting the drive circuit to the second piezoelectric actuator while connecting the sense circuit to the first piezoelectric actuator.

There is provided a control method for a piezoelectric driving device including a vibrating body including a piezoelectric element for driving and configured to vibrate when a driving signal is applied to the piezoelectric element for driving, a section to be driven that is driven by the vibration of the vibrating body, and a driving-signal generating section configured to generate the driving signal using a pulse signal generated based on a target pulse duty ratio. When the target pulse duty ratio is smaller than a predetermined value, the driving signal generated by the driving-signal generating section is an intermittently generated periodic signal.

A drive control device 100, which controls driving of a vibration type actuator 200 including a vibrator 214 that includes a piezoelectric element 203, and a rotor 207, includes amplifier circuits 11 and 12 amplifying a power supply voltage to generate a drive voltage to be applied to the piezoelectric element 203, and a microcomputer unit 1. The microcomputer unit 1 performs a control to increase the amplitude of the drive voltage to perform acceleration from when the vibration type actuator 200 is started to when a target speed of the rotor 207 is reached, decrease the frequency of the drive voltage without changing the amplitude of the drive voltage when power supplied to the piezoelectric element 203 exceeds a first power limit P-Lim.sub.1, and increase the amplitude of the drive voltage when the power falls below a second power limit P-Lim.sub.2 during an operation of decreasing the frequency.

A piezoelectric motor may include a stator, a rotor rotating about a rotational axis and at least one piezoelectric element driving the rotor and maintained by the stator. Mechanical reliability and performance levels of a piezoelectric motor may be increased in that the at least one piezoelectric element may be mounted in an oscillating housing that oscillates with respect to the stator about the pivot axis.

A piezoelectric driving device includes a first substrate having cleavability, and a piezoelectric element placed above the first substrate, wherein a cleavage direction of the first substrate and a direction in which a shear force is applied do not coincide in a plan view of the first substrate. Further, an angle formed by the cleavage direction of the first substrate and the direction in which the shear force is applied is equal to or larger than 20° in the plan view of the first substrate. Furthermore, the first substrate contains silicon single crystal.

A piezoelectric drive device for vibrating a vibrating body to make a tip of a protruding part make a rotational motion of drawing an elliptic orbit to thereby drive a driven member, wherein the vibrating body includes a substrate, a driving piezoelectric element configured to vibrate the substrate, and a detecting piezoelectric element configured to detect a vibration of the substrate, the driving piezoelectric element includes a first driving piezoelectric element for making the vibrating body perform a stretching vibration in a first direction, and a second driving piezoelectric element for making the vibrating body perform a flexural vibration in a second direction perpendicular to the first direction, the detecting piezoelectric element is arranged with the first driving piezoelectric element in the first direction, and there is provided a voltage control section for controlling a magnitude of a voltage to be applied to the first driving piezoelectric element.

There is provided a control method for a piezoelectric driving device including a vibrating body configured to vibrate when a driving signal including a periodic signal is applied to a piezoelectric element for driving, a section to be driven that is driven by the vibration of the vibrating body, and a driving-signal generating section configured to generate the driving signal using a pulse signal generated based on a target pulse duty ratio. The driving-signal generating section detects voltage amplitude generated in the piezoelectric element for driving and generates the target pulse duty ratio based on the voltage amplitude. The driving signal includes an intermittent signal formed by an output period in which the periodic signal is output and a suspension period in which the output of the periodic signal is suspended. The driving-signal generating section detects the output-period voltage amplitude and does not detect the suspension-period voltage amplitude.