A lens barrel includes an element displaced by application of voltage; an elastic body having a contact surface coming into contact with the element, a drive surface to produce a vibration wave by displacement of the element, and a plurality of grooves; a moving element come into contact with the drive surface and rotated by the vibration wave; an annular ring rotated by rotating of the moving element; and a lens moved in an optical axis direction by rotating of the annular ring; wherein the element mainly contains a material having potassium sodium niobate, potassium niobate, sodium niobate, or barium titanate, wherein a value of [(T/B)÷W] is in a range of 0.84 to 1.94, where T represents a depth of the groove, B represents a distance from a bottom part of the groove to the contact surface, and W represents a radial width of the elastic body.

A lens barrel includes an element displaced by application of voltage; an elastic body having a contact surface coming into contact with the element, a drive surface to produce a vibration wave by displacement of the element, and a plurality of grooves; a moving element come into contact with the drive surface and rotated by the vibration wave; an annular ring rotated by rotating of the moving element; and a lens moved in an optical axis direction by rotating of the annular ring; wherein the element mainly contains a material having potassium sodium niobate, potassium niobate, sodium niobate, or barium titanate, wherein a value of [(T/B)÷W] is in a range of 0.84 to 1.94, where T represents a depth of the groove, B represents a distance from a bottom part of the groove to the contact surface, and W represents a radial width of the elastic body.

A device may include a stator including a vibrating body in a plate shape having a first principal surface and a second principal surface opposed to each other, and including a piezoelectric device provided on the first principal surface of the vibrating body. A device may include a rotor directly or indirectly in contact with the second principal surface of the vibrating body. A device may include a spring in a plate shape having an opening and configured to give elastic force to the rotor in a direction from a side of the rotor to a side of the stator. A device may include a shaft inserted into the opening of the spring and having a mating portion, wherein. A device may include a shape of the opening of the spring is a noncircular shape in a plan view.

Provided is a method of manufacturing a piezoelectric element in which, at a time when the piezoelectric element is manufactured, a piezoelectric material is prevented from being exposed to a temperature higher than a Curie temperature thereof to be depolarized, to thereby significantly decrease piezoelectric properties. The method of manufacturing a piezoelectric element includes a first step of arranging a plurality of electrodes on a piezoelectric material, electrically short-circuiting two or more electrodes of the plurality of electrodes, and subjecting the piezoelectric material to heat treatment, and a second step of, after the first step, electrically opening the short circuit of the two or more electrodes at a time when a temperature of the piezoelectric material decreases to less than a temperature of the piezoelectric material at a time of the heat treatment.

An electronic device is provided, including a shell, a driving mechanism and a driven module, wherein the shell is provided with an avoidance space communicating with an inner cavity of the shell; the driving mechanism includes at least two first field deformation structural components; the first field deformation structural components are arranged in the avoidance space; the adjacent two first field deformation structural components are distributed at intervals and energizing currents are opposite; the driven module is connected to the first field deformation structural components; and when the first field deformation structural components are in a power-up state, each of the first field deformation structural components drives the driven module to rotate through deformation.

An electronic device is provided, including a shell, a driving mechanism and a driven module, wherein the shell is provided with an avoidance space communicating with an inner cavity of the shell; the driving mechanism includes at least two first field deformation structural components; the first field deformation structural components are arranged in the avoidance space; the adjacent two first field deformation structural components are distributed at intervals and energizing currents are opposite; the driven module is connected to the first field deformation structural components; and when the first field deformation structural components are in a power-up state, each of the first field deformation structural components drives the driven module to rotate through deformation.

A sensor, a movable platform, and a microwave radar sensor are provided. The sensor may include a motor, a rotating body, and a grating sensor. The motor may include a stator and a rotor rotatably connected to the stator, and the stator may have a mounting end face in an extension direction of a rotation center line of the rotor. The rotating body may be fixedly connected to the rotor. The grating sensor may include a grating code disc and a reading head assembly matched with the grating code disc. The grating code disc may be disposed on the mounting end face. The reading head assembly may be connected to the rotating body, and its position is opposite the position of the grating code disc. The reading head assembly may cooperate with the grating code disc to sense a rotation angle of the rotating body.

An ultrasonic motor is provided that includes a stator including first and second piezoelectric elements provided on a first main surface of a vibrator having a plate shape, a rotor in direct or indirect contact with a second main surface of the vibrator, and a wiring member connected to the first and second piezoelectric elements. Moreover, the wiring member includes first and second connection members connected to the first and second piezoelectric elements, a central wiring portion connected to the first and second connection members and provided in a region including a center of an axial direction, and an extended wiring portion connected to the central wiring portion. The central wiring portion is fixed to the first main surface of the vibrator and the extended wiring portion is lifted from the first main surface of the vibrator.

Provided is an injector in which adhesion between a stator and a rotor of an ultrasonic motor can be released efficiently. An injector (1) which injects a chemical liquid includes: an ultrasonic motor unit (3) including an ultrasonic motor (31); a drive mechanism (4) to be driven by the ultrasonic motor unit (3) so as to feed the chemical liquid when the ultrasonic motor (31) rotates forwardly; and a control device (5) which controls the ultrasonic motor (31) of the ultrasonic motor unit (3). The ultrasonic motor (31) includes a stator (32) and a rotor (33), and the control device (5) controls the ultrasonic motor (31) to alternately repeat forward rotation and reverse rotation so that adhesion between the stator (32) and the rotor (33) is released.

Provided is an injector in which adhesion between a stator and a rotor of an ultrasonic motor can be released efficiently. An injector (1) which injects a chemical liquid includes: an ultrasonic motor unit (3) including an ultrasonic motor (31); a drive mechanism (4) to be driven by the ultrasonic motor unit (3) so as to feed the chemical liquid when the ultrasonic motor (31) rotates forwardly; and a control device (5) which controls the ultrasonic motor (31) of the ultrasonic motor unit (3). The ultrasonic motor (31) includes a stator (32) and a rotor (33), and the control device (5) controls the ultrasonic motor (31) to alternately repeat forward rotation and reverse rotation so that adhesion between the stator (32) and the rotor (33) is released.