An energy harvester includes an elongated tubular casing extending around a longitudinal axis between opposed first and second ends. A body is arranged in the casing. A helical electrical winding is wound around the longitudinal axis. The body is arranged to move along the longitudinal axis with alternate motion away from the first end towards the second end and away from the second end towards the first end. As a result of this alternate motion, an electromotive force is produced in the at least one helical electrical winding. Furthermore, at least one of the first and second ends includes a piezoelectric transducer that is configured to co-operate in a kinetic energy transfer relationship with the at least one body to generate an electric voltage as a result of the at least one body reaching, in the alternate motion, an end-of-travel position towards the piezoelectric transducer.

An energy harvester includes an elongated tubular casing extending around a longitudinal axis between opposed first and second ends. A body is arranged in the casing. A helical electrical winding is wound around the longitudinal axis. The body is arranged to move along the longitudinal axis with alternate motion away from the first end towards the second end and away from the second end towards the first end. As a result of this alternate motion, an electromotive force is produced in the at least one helical electrical winding. Furthermore, at least one of the first and second ends includes a piezoelectric transducer that is configured to co-operate in a kinetic energy transfer relationship with the at least one body to generate an electric voltage as a result of the at least one body reaching, in the alternate motion, an end-of-travel position towards the piezoelectric transducer.

According to one aspect of the invention, a circuit board for a display device includes: a first layer; a first lead line disposed on the first layer; and a sound generator disposed on the first layer, and the sound generator including: a first electrode to receive a first driving voltage; a second electrode to receive a second driving voltage; and a second layer disposed between the first electrode and the second electrode to contract or expand according to the first driving voltage and the second driving voltage; and a first solder to electrically communicate the first lead line and the first electrode.

According to one aspect of the invention, a circuit board for a display device includes: a first layer; a first lead line disposed on the first layer; and a sound generator disposed on the first layer, and the sound generator including: a first electrode to receive a first driving voltage; a second electrode to receive a second driving voltage; and a second layer disposed between the first electrode and the second electrode to contract or expand according to the first driving voltage and the second driving voltage; and a first solder to electrically communicate the first lead line and the first electrode.

A robotic cleaning appliance includes a housing to which is coupled a surface treatment item and a sensor assembly with first and second transducers and an acoustic interface. The first sonic transducer transmits sonic signals through an acoustic interface and out of a first acoustic opening toward a surface beneath the robotic cleaning appliance. The sonic signals reflect from the surface as corresponding returned signals received by the second sonic transducer via a second acoustic opening port of the acoustic interface. A first annular ring is defined around the first acoustic opening port and a second annular rings is defined around the second acoustic opening port. The annular ring attenuate direct path echoes between the acoustic opening ports. The first and second acoustic opening ports are coupled the first and sonic transducers, respectively, via first and second horns; and the horns are tilted from orthogonal with the surface.

A semi-wave transducer is provided that comprises a circular or elliptic transduction shell that has sidewalls captured between identical opposing upper and lower circular or elliptic conical segments (platens), each having a surface geometry of a radially symmetric wave shape that includes a center region and a rim wherein the distance between the center region of the upper and lower platens greater than the distance between the rims of the upper and lower platens. In some embodiments, the surface geometry of the platens may be a jinc function or a recurve function.

The present disclosure relates to a display apparatus, especially having a display panel generating sounds. A display apparatus according to the present disclosure includes: a display module; a back cover at a rear surface of the display module; a depression recessed into the back cover from a first surface of the back cover with a first width and a first depth; a penetration through from a second surface of the back cover to the depression with a second width smaller than the first width and a second depth corresponding to a difference between a thickness of the back cover and the first depth; and a first piezo vibration unit disposed at a stepped portion between the penetration and the depression.

The present disclosure relates to a display apparatus, especially having a display panel generating sounds. A display apparatus according to the present disclosure includes: a display module; a back cover at a rear surface of the display module; a depression recessed into the back cover from a first surface of the back cover with a first width and a first depth; a penetration through from a second surface of the back cover to the depression with a second width smaller than the first width and a second depth corresponding to a difference between a thickness of the back cover and the first depth; and a first piezo vibration unit disposed at a stepped portion between the penetration and the depression.

A sensor has a sensor element (5) with two opposite sides (11, 9) and an interconnect (7) with first and second terminal segments (13B, 13F) interconnected by an intermediate segment (42). The first terminal segment (13F) is positioned against a first side (11) of the sensor element and comprises a first contact terminal (50). The second terminal segment (13B) is positioned against the second side (9) of the two opposite sides of the sensor element and comprises a second contact terminal (52) on a surface facing the second side (11). There are third and fourth, external, contact terminals (54, 56). The interconnect provided electrical connections between the first and fourth contact terminals (50, 56) and between the second and third contact terminals (52, 54).

A Piezoelectric Micromachined Ultrasonic Transducer (PMUT) device includes a substrate, an edge support structure connected to the substrate, and a membrane connected to the edge support structure such that a cavity is defined between the membrane and the substrate, the membrane configured to allow movement at ultrasonic frequencies, the membrane having non-uniform stiffness. The membrane includes a piezoelectric layer, a first electrode and a second electrode coupled to opposing sides of the piezoelectric layer, and a mechanical support layer coupled to one of the first electrode and the second electrode.