This application relates to methods and apparatus for driving a transducer with switching drivers. A switching driver has first and second supply node for receiving supply voltages and includes an output bridge stage, a capacitor and a network of switches. The network of switches is operable in different switch states to provide different switching voltages to the output bridge stage. A controller is configured to control the switch state of the network of switches and a duty cycle of output switches of the output bridge stage based on an input signal to generate an output signal for driving the transducer.

A control method for a piezoelectric drive device having a vibrating portion including a piezoelectric element and a transmitting portion, synthesizing longitudinal vibration and flexural vibration by energization to the piezoelectric element to vibrate the vibrating portion and make elliptic motion of the transmitting portion, and moving a driven member by the elliptic motion of the transmitting portion, includes controlling a movement amount of the driven member by changing amplitude of the longitudinal vibration with amplitude of the flexural vibration kept constant.

A control method for a piezoelectric drive device having a vibrating portion including a piezoelectric element and a transmitting portion, synthesizing longitudinal vibration and flexural vibration by energization to the piezoelectric element to vibrate the vibrating portion and make elliptic motion of the transmitting portion, and moving a driven member by the elliptic motion of the transmitting portion, includes controlling a movement amount of the driven member by changing amplitude of the longitudinal vibration with amplitude of the flexural vibration kept constant.

A vibration actuator that is capable of reducing difference of vibration velocities when a contact member is driven using a plurality of vibrators includes a vibrator device and the contact member, which moves relative to the vibrator device. The vibrator device includes the plurality of vibrators, which are connected in series, and a plurality of inductors, which are connected in parallel to the respective vibrators.

A contact body that makes it possible to easily verify whether or not the resin has been properly impregnated in the pores. A metallic sintered body having a plurality of pores, as a main body, is in contact with a vibration element in a vibration actuator. The contact body includes a sliding portion that has a sliding surface in contact with the vibration element, and a non-sliding portion adjacent to the sliding portion and not in contact with the vibration element. The non-sliding portion is provided with a resin lump containing hard particles and resin, and the resin lump is formed to be lower in height in a vertical direction than the sliding surface. In the sliding portion, part of hard particles and resin is exposed on the sliding surface.

A vibration device is provided that includes a vibration element with a piezoelectric vibrator and a driving device that causes the vibration element to vibrate. The vibration element includes a translucent body and the piezoelectric vibrator is electrically coupled to the driving device. The driving device includes a first circuit that applies an electric signal to the piezoelectric vibrator to render the vibration element in a resonant state, a second circuit that applies an electric signal to the piezoelectric vibrator according to a feedback signal output from the piezoelectric vibrator, and a switch that switches coupling between the first circuit and the piezoelectric vibrator and coupling between the second circuit and the piezoelectric vibrator at a certain timing.

A method of treating a calculi mass can include using an ultrasonic probe to produce acoustic energy and fragment the mass. The method can include varying the frequency at which fragmentation occurs to treat the mass with a resonant frequency. The ultrasonic probe can have a distal tip for contact with the mass, where the tip has a morphology for concentrating stress on the mass. The ultrasonic probe can have two or more ultrasonic horns to allow for higher voltage and power levels.

A vibration device includes a cylindrical body including an opening, a light-transmissive cover joined to the cylindrical body, a piezoelectric element directly or indirectly joined to the cylindrical body and including first and second main surfaces, and a power feeder joined to the piezoelectric element. The power feeder includes a substrate including first and second surfaces, first and second power feeding electrodes on the first surface or the second surface, and first and second external connection electrodes. The power feeder sandwiches the piezoelectric element in a thickness direction, and the first and second power feeding electrodes are joined to the first main surface or the second main surface of the piezoelectric element. Portions of the substrate, which are not located on the first and second main surfaces of the piezoelectric element, are bent to sandwich the piezoelectric element.

This application relates to methods and apparatus for driving a transducer with switching drivers. A switching driver has first and second supply node for receiving supply voltages and includes an output bridge stage, a capacitor and a network of switches. The network of switches is operable in different switch states to provide different switching voltages to the output bridge stage. A controller is configured to control the switch state of the network of switches and a duty cycle of output switches of the output bridge stage based on an input signal to generate an output signal for driving the transducer.

A fluid control valve can suppress heat generation when discharging charges from a piezo actuator for contraction and reduce energy necessary to drive the piezo actuator. The fluid control valve includes a piezo actuator and a drive circuit connected to the piezo actuator is adapted so that the drive circuit includes: a flyback transformer including a primary side coil connected to a DC power supply DV and a secondary side coil connected to the piezo actuator; a charge switch that is connected to the primary side coil and switched from on to off when the piezo actuator charges; a discharge switch that is connected to the secondary side coil and switched from off to on when the piezo actuator discharges; and a regenerative capacitor that is connected to the primary side coil and into which electric energy due to the discharge of the piezo actuator is regenerated.