A piezoelectric motor includes a driven body configured to rotate around a rotation axis, a first piezoelectric vibrator configured to transmit a driving force to the driven body, a moving mechanism configured to move the first piezoelectric vibrator in directions approaching and separating from the rotation axis, and a second piezoelectric vibrator configured to transmit a driving force to the moving mechanism. The moving mechanism includes a screw shaft disposed along the directions and configured to rotate around an axis with the driving force of the second piezoelectric vibrator and a holding section configured to screw with the screw shaft and hold the first piezoelectric vibrator.

A piezoelectric motor includes a driven member rotating around a rotation axis, and a plurality of piezoelectric vibrators rotating the driven member by transmitting drive forces to the driven member. The plurality of piezoelectric vibrators includes a first piezoelectric vibrator and a second piezoelectric vibrator at a larger distance from the rotation axis than the first piezoelectric vibrator. The control method for the driven member includes, for acceleration of the driven member, rotating the driven member by the drive force of the second piezoelectric vibrator when a rotation velocity of the driven member is lower than a first velocity, and rotating the driven member by the drive force of the first piezoelectric vibrator when the rotation velocity of the driven member is equal to or higher than the first velocity.

A piezoelectric drive device includes a vibrating part which has a piezoelectric element, and drives a driven part using the piezoelectric element, and a first plate spring part configured to bias the vibrating part in a first direction from the vibrating part toward the driven part. The first plate spring part extends toward a second direction crossing the first direction, the first plate spring part is disposed so as to be opposed to the vibrating part in a third direction perpendicular to the first direction and the second direction, and when dividing the first plate spring part into a first portion and a second portion farther from the vibrating part than the first portion so that a length along the third direction is equally divided, a volume of the second portion is larger than a volume of the first portion.

Provided are a piezoelectric ceramics which does not contain lead, has small temperature dependence of a piezoelectric constant within an operating temperature range, and has high density, a high mechanical quality factor, a satisfactory piezoelectric constant, and a small surface roughness, and a method of manufacturing the piezoelectric ceramics. The method of manufacturing a piezoelectric ceramics is characterized by including: sintering a compact containing a raw material at 1,000° C. or more to obtain a sintered compact; abrading the sintered compact; and annealing the abraded sintered compact at a temperature of 800° C. or more and less than 1,000° C.

A piezoelectric drive device includes: a vibrating body having a first surface and a second surface provided with a recessed portion; and a piezoelectric element provided on the first surface. The recessed portion and the piezoelectric element have an overlap region when viewed in a normal direction of the second surface.

A piezoelectric driving device includes a substrate, a first insulating film disposed on the substrate, a piezoelectric element for driving disposed on the first insulating film and configured to vibrate the substrate, a piezoelectric element for detection configured to detect the vibration of the substrate, a wire for driving electrically connected to the piezoelectric element for driving, a wire for detection electrically connected to the piezoelectric element for detection, and a lower layer wire disposed between the first insulating film and the substrate and set to fixed potential. At least one of the wire for driving and the wire for detection overlaps at least a part of the lower layer wire.

A piezoelectric motor comprises a frame having a first frame side and a second frame side; a first actuator assembly and a second actuator assembly. The first actuator assembly comprises a first piezoelectric actuator and two rollers, each of the rollers is pressed between the first piezoelectric actuators and the first frame side the second actuator assembly comprises a second piezoelectric actuator and two rollers, each of the rollers is pressed between the second piezoelectric actuator and the second frame side. The motor further comprises at least one pre-loaded spring provided between the first actuator assembly and the second actuator assembly, pushing the first actuator assembly and the second actuator assembly against the first frame side and the second frame side, respectively.

A piezoelectric motor includes a piezoelectric actuator, a holding member that holds the piezoelectric actuator, a housing in which the piezoelectric actuator and the holding member are placed, a first positioning pin that positions the holding member and the housing, and a first fixing part that fixes the first positioning pin. In the piezoelectric motor, the first positioning pin is fixed to one of the holding member and the housing, and a first hole portion in which the first positioning pin is placed is provided in the other of the holding member and the housing. The first fixing part fixes relative positions of the first hole portion and the first positioning pin.

A piezoelectric driving device includes a supporting section, a first moving section movable in a first direction relative to the supporting section, a second moving section movable in a second direction relative to the first moving section, a first driving section configured to drive a first piezoelectric actuator to move the first moving section relative to the supporting section and stop the first piezoelectric actuator to hold the first moving section on the supporting section, and a second driving section configured to drive a second piezoelectric actuator to move the second moving section relative to the first moving section and stop the second piezoelectric actuator to hold the second moving section on the first moving section. A first holding force for holding the first moving section on the supporting section and a second holding force for holding the second moving section on the first moving section are different from each other.

A piezoelectric drive device includes a piezoelectric element, a vibrating plate with a concave portion provided in a side surface, and a projecting portion provided between two side surfaces of the concave portion and having a spherical shape, an elliptical shape, or an egg shape, wherein a plurality of the piezoelectric elements and a plurality of the vibrating plates are stacked, and the concave portion includes a bottom surface.