The invention relates to an annular or hollow cylindrical ultrasonic actuator, on the end faces of which are arranged n≥2 friction elements, and on the outer peripheral surface of which are arranged 2 n excitation electrodes, spaced apart from one another in each case by a separating gap, each of the friction elements being arranged in the region of a separating gap, wherein, between friction elements that are adjacent with respect to the periphery of the ultrasonic actuator and are located on different end faces, two excitation electrodes are arranged such that, when the ultrasonic actuator is electrically excited, the friction elements of both end faces simultaneously perform a movement which is suitable for driving an element to be driven to rotate in the same direction. The invention further relates to an ultrasonic motor having an ultrasonic actuator of this kind and having a holding device in which the ultrasonic actuator is inserted.

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 device and method using the electromechanical properties of piezoelectric materials to generate and deliver electrical power to a high speed electrically powered rotatable shaft. The device has a stationary module that is connected to an electrical source; and has a rotatable module, which is mechanically connected to the electrically powered rotatable shaft. The rotatable module rotates relative to the stationary module. When the stationary module is electrically energized, the stationary piezoelectric component expands and causes the rotatable piezoelectric component to compress. When the rotatable piezoelectric component compresses, it generates electrical power transferred to the electrically powered rotatable shaft. Thus, electrical energy can be delivered to the electrically powered rotatable shaft without a direct electrical connection. The present invention is particularly useful in applications requiring large diameter through-hole dimensions.

A vibration wave motor includes a vibrator including a piezoelectric element and a vibratory plate, a friction member configured to make a frictional contact with the vibrator, a pressurizer configured to press the vibrator and the friction member against each other, and a guide unit configured to guide a relative movement between the vibrator and the friction member. The guide unit includes a plurality of rollers configured to move relative to the pressurizer, and a guide member that includes a guide portion, the guide portion being configured to extend along a relative movement direction between the vibrator and the friction member and to guide the plurality of rollers. The guide member includes a reinforcer configured to extend along the relative movement direction near a roller closest to a center position of a pressing force by the pressurizer.

A vibration-wave motor includes a vibrator, a first holding member configured to hold the vibrator, a second holding member configured to hold the first holding member, a plurality of pressing members arranged around the vibrator and configured to press the vibrator against a contacting member that contacts the vibrator, a movable plate disposed opposite to the vibrator with respect to the contacting member, and a coupling part configured to couple the second holding member and the movable plate with each other. The vibrator and the contacting member move relatively to each other due to a vibration generated by the vibrator. One of the second holding member and the movable plate includes a transmitting part configured to transmit a driving force of the vibration-wave motor to a driven member.

A first member, a second member, a bearing that rotatably supports the second member about a rotation axis relative to the first member, a driven member placed on the first member, and a plurality of piezoelectric actuators that transmit driving forces for rotating the second member about the rotation axis relative to the first member to the driven member are provided, and the piezoelectric actuators are supported by the second member while being pressed against the first member or the member fixed thereto, and, as seen from a direction along the rotation axis, a center of pressing forces from the plurality of piezoelectric actuators to the driven member is located inside of an outer circumferential part of the bearing.

A quick assembly structure used for a driver is provided. The driver comprises a motor, an upper shell and a lower shell, and the upper shell is combined with the lower shell. The quick assembly structure comprises a clamping cavity formed in the lower shell. The upper shell is provided with a clamping piece to be inlaid in the clamping cavity. One end of the clamping piece is fixedly connected to the upper shell, and the other end of the clamping piece is an open end. A clamping hole is formed in a side of the lower shell, and the upper shell is provided with a first hook to be inlaid in the clamping hole.

Provided is a vibration wave motor including: a vibrator; a friction member that comes into frictional contact with the vibrator; a press member that pressurizes the vibrator and the friction member into frictional contact with each other; a first guide member and a second guide member that guide the vibrator and the friction member so as to allow relative movement of the vibrator and the friction member; a hold member that holds the friction member and the first guide member; and a fixing member. The friction member and the first guide member are fixed to the hold member with the fixing member.

In a vibration type motor, a vibrator unit including a vibrator configured to vibrate, and a friction member unit including a friction member which the vibrator contacts relatively moving in a first direction. The vibrator unit is displaceable relative to the friction member unit in a second direction orthogonal to the first direction, and presses the vibrator against the friction member in the second direction. The friction member unit includes a stopper that contacts the vibrator unit so as to restrict the vibration unit from displacing, by an amount exceeding a predetermined amount, in the second direction. The stopper extends in the first direction, a distance greater than a length, in the first direction, of an area of the friction member which the vibrator contacts, and the stopper projects from the friction member toward the vibrator in the second direction when viewed from the first direction.