A vibration actuator difficult to be affected by an external force. A vibration element is held by a shaft. A driven element is held in pressure contact with an elastic body, and a bearing member is joined to the driven element in a manner rotatable about the shaft as a rotational axis. Vibrations excited in the vibration element cause the vibration element and the driven element to rotate relative to each other about the shaft. In the driven element, a connecting portion connects between a main body and a gear provided outside the main body. The degree of freedom of the main body with respect to the bearing member is restricted in other directions than a direction of rotation thereof and a thrust direction of the shaft. The connecting portion has a lower flexural rigidity in a direction parallel to the rotational axis than the main body and the gear.

The piezoelectric vibrator element is miniaturized, and at the same time, the vibration leakage is suppressed. The piezoelectric vibrator element is formed so that the total length L1 of the piezoelectric vibrator element, the length L2 of the base, the width L3 of the connection part, the length L4 of the support arm part fulfill all of the following conditions A through C, Condition A: 0.1L2/L10.2, Condition B: 0.4L3/L20.6, Condition C: L4/L10.7. While the miniaturization is realized by shortening the base due to the condition A, the distance via the base can be elongated due to the condition B. Further, by increasing the length of the support arm parts due to the condition C, it is possible to increase the total mass of the path transmitting the vibration to absorb the vibration to thereby further suppress the vibration leakage.

A piezoelectric vibrator element includes a pair of vibrating arms extending from a base, and having a groove on each of opposing principal surfaces in the longitudinal direction of the vibrating arms. Two systems of excitation electrodes are included on the side surfaces and the opposing principal surfaces, and in the grooves of the vibrating arms. A width of a bank part formed by a side surface of the vibrating arms and a side surface of the groves is W0, and the separation distance between the excitation electrodes on the opposing principal surfaces is W1, such that 1 m<W1<3 m and W0>W1.

When stopping a vibration type actuator at a final target stopping position, driving frequency and phase difference of AC signals input to a piezoelectric element are set in accordance with a first deviation obtained from a command position sequentially determined and a relative position of a vibrating member and driven element, and also pulse duty is adjusted in accordance with a second deviation obtained from a final target stopping position and the relative position.

An ultrasonic motor includes a vibrator configured to generate a vibration, a relatively movable member configured to be movable by the vibrator, wherein the relatively movable member is movable relatively according to the vibration of the vibrator, a holding unit configured to hold the vibrator, wherein the holding unit includes a first holding member configured to hold the vibrator and a second holding member; and a damping member provided between the vibrator and the second holding member and configured to reduce a vibration transmitted to the second holding member, a pressure unit configured to press the vibrator against the relatively movable member, wherein the second holding member is configured to press the vibrator against the relatively movable member, and wherein the first holding member is made of a material having a higher damping capability against the vibrator than a material of the second holding member.

The present invention provides a vibration-type actuator that makes it possible to improve and stabilize yields. A vibration-type actuator includes a vibrator including an elastic body with a protrusion having a contact portion, and an electromechanical transducer attached to a surface of the elastic body; and a flexible printed circuit board having an electrode portion and attached to the electromechanical transducer. There is a space between the contact portion and the electromechanical transducer. No end portion of the electrode portion of the flexible printed circuit board is overlapped with the space in a direction perpendicular to the surface of the elastic body.

A driving apparatus of a vibration-type actuator includes a driving circuit configured to drive a vibration unit including a plurality of vibrators, a detection unit configured to detect a sum of power consumption consumed by the plurality of vibrators, and a driving frequency setting unit configured to set a driving frequency within a frequency range depending on the sum of power consumption detected by the detection unit.

A control device includes: a controller that outputs control, signals pertaining to at least two directions, respectively, based on predetermined gains in a normal operation mode, and outputs control signals based on gains set with respect to the two directions, respectively, in a learning operation mode; a controlled amount calculating unit that receives the control signals and outputs signals pertaining to drive parameters with respect to at least two motors, respectively, wherein the controlled amount calculating unit includes: a characteristic difference calculating unit that calculates characteristic differences between at least the two motors based on the control signals; and a gain compensator that corrects controlled amount pertaining to drive parameters of at least the two motors according to the calculated characteristic differences of at least the two motors, and outputs the signals.

The actuator includes a vibration plate including a fixing portion for fixing the vibration plate to a holding member, and a connection portion for connecting a center portion and the fixing portion, and is provided between a surface and a friction-sliding surface in a direction in which the vibration plate is pressed against the rotor by a pressurizing force produced by a pressure member. When finishing a surface on which a piezoelectric device is to be fixed to the vibration plate to a uniform surface by polishing, a decrease in the performance of the ultrasonic motor due to deformation of the vibration plate that is caused by warping of support portions that extend from both ends thereof or by burrs or the like can be prevented, and the time required to polish the vibration plate can be reduced.

A vibration-type actuator which is downsized and stably holds the position of a vibrating body. In the vibrating body, it is possible to excite vibrations in a first bending vibration mode with two nodal lines that do not cross each other but cross short sides of an elastic body, and no nodal line that connects two long sides of the elastic body together, and a second bending vibration mode in which amplitude peaks vibration in an out-of-plane direction of a flat-shaped plane of the elastic body lies in respective six areas formed by dividing the flat-shaped plane, and in the adjoining areas, vibrations at the amplitude peaks are in opposite phases. Combined vibrations in the first and second bending vibration modes cause an oval motion of the projecting portion, moving the vibrating body and a driven body relatively to each other in a lateral direction of the elastic body.