A piezoelectric cooling system and method for driving the cooling system are described. The piezoelectric cooling system includes a first piezoelectric cooling element and a second piezoelectric cooling element. The first piezoelectric cooling element is configured to direct a fluid toward a surface of a heat-generating structure. The second piezoelectric cooling element is configured to direct the fluid to an outlet area after heat has been transferred to the fluid by the heat-generating structure.

A piezoelectric cooling system and method for driving the cooling system are described. The piezoelectric cooling system includes a first piezoelectric cooling element and a second piezoelectric cooling element. The first piezoelectric cooling element is configured to direct a fluid toward a surface of a heat-generating structure. The second piezoelectric cooling element is configured to direct the fluid to an outlet area after heat has been transferred to the fluid by the heat-generating structure.

Provided is a piezoelectric element vibration apparatus that generates vibration by applying a driving voltage to a piezoelectric vibrator, wherein a piezoelectric element layer is arranged on an electrode substrate made of a conductive material, an insulation member for preventing the applied driving voltage from leaking is formed on the piezoelectric element layer, and the piezoelectric element vibration apparatus has various types of forms in order to attach and install the piezoelectric vibrator. As a result, the piezoelectric element vibration apparatus has the effects wherein: installation is possible simply by attachment, thereby simplifying the assembly process; installation in any position is possible because the thickness of the piezoelectric element vibration device is made to be thin; the vibration volume can increase and the vibration noise can decrease while minimizing the thickness.

An acoustic resonator includes a wafer and a first phononic crystal disposed on the wafer to define an acoustic waveguide so as to propagate an acoustic wave along a propagation direction. The first phononic crystal includes a first two-dimensional (2D) array of metal stripes having a first period on the propagation direction. The apparatus also includes a second phononic crystal and a third phononic crystal disposed on two sides of the first phononic crystal and having a different period from the first period. The second phononic crystal and the wafer define a first reflector to reflect the acoustic wave. The third phononic crystal and the wafer define a second reflector to reflect the acoustic wave.

A fluid actuator includes an actuating portion, a piezoelectric unit, a conduction unit, and a levelness regulating portion. The actuating portion includes a first actuating area, a second actuating area, and at least one connecting section between the two actuating areas. The piezoelectric unit includes a first signal area and a second signal area. The two signal areas are provided in the same plane and are isolated from each other by an isolating portion. The piezoelectric unit corresponds in position to the first actuating area of the actuating portion. The conduction unit includes a first electrode and a second electrode. The first signal area of the piezoelectric unit is electrically connected to the first electrode, and the second signal area of the piezoelectric unit to the second electrode. The levelness regulating portion, the piezoelectric unit, and the conduction unit are located on the same side of the actuating portion.

A piezoelectric actuator is disclosed that may include a insulating layer, individual electrodes, a common electrode, and a piezoelectric layer. The common electrode may include divisional electrodes that are connected with one another. The individual electrodes may be disposed between the insulating layer and the piezoelectric layer while the piezoelectric layer may be disposed between the individual electrodes and the common electrode. Further, the divisional electrodes may be configured to face the individual electrodes.

A piezoelectric actuator is disclosed that may include a insulating layer, individual electrodes, a common electrode, and a piezoelectric layer. The common electrode may include divisional electrodes that are connected with one another. The individual electrodes may be disposed between the insulating layer and the piezoelectric layer while the piezoelectric layer may be disposed between the individual electrodes and the common electrode. Further, the divisional electrodes may be configured to face the individual electrodes.

An ultrasonic motor is provided with increased torque without an increase in size. The ultrasonic motor includes a stator having a plate-shaped vibrating body including first and second main surfaces and a piezoelectric element on the first main surface; and a rotor in contact with the second main surface. The piezoelectric element is disposed along a circumferential direction of a traveling wave so as to generate the traveling wave circulating around an axial direction Z by vibrating the vibrating body. The piezoelectric element vibrates the vibrating body in a vibration mode including a nodal line extending in the circumferential direction. A mass addition portion is provided along the circumferential direction on at least one of the first and second main surfaces of the vibrating body 3, and the mass addition portion is located outside the nodal line in a direction perpendicular to the axial direction Z.

An ultrasonic motor is provided with increased torque without an increase in size. The ultrasonic motor includes a stator having a plate-shaped vibrating body including first and second main surfaces and a piezoelectric element on the first main surface; and a rotor in contact with the second main surface. The piezoelectric element is disposed along a circumferential direction of a traveling wave so as to generate the traveling wave circulating around an axial direction Z by vibrating the vibrating body. The piezoelectric element vibrates the vibrating body in a vibration mode including a nodal line extending in the circumferential direction. A mass addition portion is provided along the circumferential direction on at least one of the first and second main surfaces of the vibrating body 3, and the mass addition portion is located outside the nodal line in a direction perpendicular to the axial direction Z.

A first power supply member and a second power supply member are arranged on the same side of a first member in a thickness direction of an actuator. The first power supply member includes a first external connection terminal. The second power supply member includes a second external connection terminal. The first external connection terminal and the second external connection terminal are arranged on the same positions in the thickness direction. A second insulating layer is arranged between the second power supply member and a frame body. A far end side portion on an opposite side to a side, on which the first external connection terminal protrudes, in the first power supply member is bent toward the frame body to be electrically connected with the frame body.