An ultrasonic actuator with increased radiating surface is presented. The increased radiating surface is provided by a plurality of piezoelectric stacks that are each compressed by action of a respective bolt against a common backing structure of the actuator. According to one aspect, each of the stacks includes a plurality of stacked piezoelectric rings with the respective bolt arranged through the central opening of the rings. According to another aspect, one or both of the backing structure and the horn of the actuator include tuning grooves and/or tuning slots to produce amplitude uniformity of displacement through the actuator. According to another aspect, the radiating surface has a symmetrical shape about an axial direction of the actuator with a lateral dimension that is in a range between one quarter and one half of the wavelength of operation of the actuator.

Provided is a laminated piezoelectric element is formed by folding back and laminating a piezoelectric film having an electrode layer and a protective layer on both sides of a piezoelectric layer in which piezoelectric particles are dispersed in a matrix. In the laminated two layers of the piezoelectric film, in a case where a thickness of a central portion thereof is a center thickness and a position up to twice the center thickness in a direction from the folded side end part toward the center is the folded-back portion, there is a position at which the thickness is greater than the center thickness in the folded-back portion, and there is an air gap in the folded-back portion or the air gap is filled with a cementing agent. The laminated piezoelectric element is able to prevent peeling of the electrode layer and the like in the folded-back portion in the laminated piezoelectric element in which the piezoelectric film is folded back and laminated. An electroacoustic transducer uses the laminated piezoelectric element.

The invention relates to a toilet cleaning tool comprising: a handle; a vibration member attached at a free end of the handle, wherein said vibration member includes an emitting surface for emitting vibrational waves;
wherein the toilet cleaning tool further includes one or more spacers arranged around the vibration member to keep the vibration member free of the toilet bowl during cleaning.

An ultrasonic surgical tool system with a tip capable of simultaneously vibrating in plural modes. The system includes a console capable of supplying a drive signal to the tip that includes plural components. Each component has a frequency characteristic that is based in part on the equivalent of current through the mechanical components of the tip. The frequency components are different from each other. Based on the application of drive signal the tip undergoes non-linear vibrations.

A high frequency ultrasound array having a number of transducer elements that are formed in sheet of piezoelectric material. A frame having a coefficient of thermal expansion similar to that of the piezoelectric material surrounds the piezoelectric material and is separated from the piezoelectric material by an epoxy material. Kerf cuts that define the individual elements in the sheet of piezoelectric material extend across a full width of the sheet. In some embodiments, sub-dice kerf cuts that divide a single transducer element into two or more sub-elements also extend all the way across the width of the sheet. A lens positioned in front of the transducer elements can have a radius machined therein to focus ultrasound signals. The frame, transducer elements and lens are bent or curved with the desired radius to focus ultrasound signals.

The present invention provides an image engraving apparatus capable of precisely driving a stylus to improve accuracy of image engraving. The image engraving apparatus has a vibration actuator fixed to a floating base and having an output portion configured to output vibration generated by deformation of piezoelectric elements, a stylus supported with a stylus holder to be vibrated and engrave an image on a medium to be engraved, a supporting spring supporting the stylus holder, and a retainer positionally adjustably supported to the floating base to come into contact with the medium.

The invention describes a device comprising at least one emitter of P-waves and/or S-waves, preferably shear waves, more preferably axisymmetric waves, and at least one wave receiver, wherein the receiver or receivers are disposed concentrically, and the disposition of the emitters and receivers allows same to simultaneously come into direct contact with a specimen, the structure of which it is desired to characterise. Also described is a method for characterising the spatial distribution of mechanical parameters of a specimen, based on the emission of shear waves and the subsequent reception thereof.

An acoustic transducer, in particular for an ultrasonic sensor, is proposed. The acoustic transducer has a functional group, the functional group encompassing a diaphragm cup and at least one electroacoustic transducer element. The acoustic transducer furthermore has a housing. The diaphragm cup encompasses a vibration-capable diaphragm and an encircling wall, as well as at least one electroacoustic transducer element, the transducer element being embodied to excite the diaphragm to vibrate and/or to convert vibrations of the diaphragm into electrical signals. The diaphragm cup is constituted from a plastic material, the at least one transducer element being integrated into the vibration-capable diaphragm, the transducer element having an electrically active polymer.

Systems and methods for the ultrasonic disruption of biofilm and algae growth on underwater structures utilize an ultrasonic actuator that produces a natural frequency in the ultrasonic range. In some embodiments, the ultrasonic actuator includes one or more piezoelectric transducers.

Disclosed is a connection device for piezoceramics of an ultrasonic transducer, comprising a nut (1), an ultrasonic transducer (5) having a screw structure and to be used with the nut (1), and a plurality of piezoceramics (3) and a plurality of metal sheets (4) fitted on an outer circumference of the screw of the ultrasonic transducer (5) and arranged at intervals. The connection device for the piezoceramics of the ultrasonic transducer further comprises a washer (2) located between the nut (1) and the piezoceramics (3), and the washer (2) is provided with a through hole through which the screw passes. The connection device has high connecting precision, strong working stability, and high working reliability.