A rotary piezoelectric motor (1), in particular for a timepiece, including a rotor (3) configured to rotate and actuate a mechanical device, and a stator (2) configured to rotate the rotor (3), the stator (2) including a piezoelectric actuator provided with a resonator (29) arranged to perform an oscillatory motion, and a fixed element (4). The resonator in a movable element (5) arranged at a distance from the fixed element (4) and connected to the fixed element (4), the piezoelectric actuator being configured to move the movable element (5) against the rotor (3) to make it rotate, the movement of the movable element (5) making the rotor (3) rotate in a first direction.

This application relates to a drive assembly, a motor, and a terminal. The drive assembly includes a stator and a rotor. The stator includes an excitation part, a vibration part, a first fixed part, and a pushing part. The vibration part is connected to the excitation part. The first fixed part is connected to the vibration part, and the vibration part is located between the excitation part and the first fixed part along a first direction L. The pushing part is connected to the vibration part and the rotor. The excitation part is capable of vibrating, and the excitation part is capable of driving the vibration part to act. Under limiting by the first fixed part, the vibration part is capable of vibrating at least along the first direction L and a second direction W.

A vibration-type actuator capable of suppressing reduction in holding torque or holding force under influence of humidity. A vibration-type actuator 10 includes a vibrating body 2 and a driven body 1. The vibrating body 2 has a piezoelectric element 2c and an elastic body 2b. The driven body 1 is in contact with the vibrating body 2. The vibration-type actuator 10 moves the vibrating body 2 and the driven body 1 relatively to each other by vibration excited to the vibrating body 2. At least one of a first contact portion of the vibrating body 2 and a second contact portion of the driven body 1 includes a stainless-steel sintered body with pores and at least some of the pores are impregnated with a resin.

A control method for a piezoelectric motor having a vibrating portion including a piezoelectric element and a transmitting portion transmitting vibration of the vibrating portion to a driven member, and synthesizing longitudinal vibration and flexural vibration by energization of the piezoelectric element to vibrate the vibrating portion and elliptically move the transmitting portion and moving the driven member by the elliptical motion, includes changing an orbit of the elliptical motion according to a load received by the transmitting portion.

An ultrasonic motor includes a vibration section having a piezoelectric element configured to generate vibration by receiving a drive voltage, a driven section, a convex section connected to the vibration section and configured to transmit vibration of the vibration section to the driven section, a drive circuit configured to generate the drive voltage, an encoder configured to detect a movement amount of the driven section, a storage section configured to store a specified voltage value, and a determination section configured to receive position information from the encoder when the driven section starts to move and a voltage value at the time of start up from the drive circuit and to determine that least one of the convex section or the driven section is worn out when the voltage value at the time of start up is larger than the specified voltage value.

A drive control circuit restores a holding force when a vibrator and a driven body have been left at a standstill for a long time period and when they are used in a high-humidity environment. A drive circuit outputs an alternating-current signal, which is to be applied to an electro-mechanical energy conversion element, based on an output from a control unit. The control circuit controls the drive circuit with first timing such that elliptical motion produced in the vibrator takes a path of which a component parallel to a driving direction of the driven body is large as compared to such a path that a speed at which the driven body is driven is the maximum. The first timing is different from second timing with which relative positions of the vibrator and the driven body are changed.

A piezoelectric driving device includes a substrate, a plurality of piezoelectric elements disposed on the substrate, a first groove section provided between the plurality of piezoelectric elements, and a first wire provided in at least a part of a side surface and a bottom section of the first groove section.

A piezoelectric drive device includes a substrate, a convex portion coupling to the substrate and transmitting drive power to a driven member, first drive piezoelectric elements placed on the substrate and vibrating the substrate in Y directions in which the substrate and the convex portion are arranged, second drive piezoelectric elements placed on the substrate and vibrating the substrate in Z directions orthogonal to the Y directions, a reference piezoelectric element placed on the substrate, receiving the vibration in the Y directions, and outputting a detection signal, and a concave portion placed side by side with the reference piezoelectric element in the Z directions in a plan view from an X direction orthogonal to the Y directions and the Z directions.

A vibration driving device that achieves low cost and high accuracy while reducing driving load. A drive unit has a vibrator with a projection and generates driving force by vibrating the vibrator. A first unit has a contact portion with which the projection is in pressure contact in a first direction. A second unit rotates relative to the first unit around a rotation axis parallel to the first direction by the driving force. Three or more support members are between the first and second units in the first direction to support the first and second units rotatably. The support members are positioned such that, during relative rotation of the first and second units, a contact point at which the projection contacts the contact portion is always located in at least one of triangular areas formed by connecting any three support members with straight lines when viewed in the first direction.

One aspect of the invention relates to a vibration type drive device including: a mechanical energy application element; a resilient member provided with the mechanical energy application element; a driven member subjected to a relative displacement with respect to the resilient member due to a vibration excited by the resilient member, wherein the resilient member includes a conductive material, and does not constitute an electric closed loop.