Abstract: An embodiment provides electrical energy from a source on one side of a medium to a load on the other side of the medium, the embodiment including a first piezoelectric to generate acoustic energy in response to electrical energy from the source, and a second piezoelectric to convert the received acoustic energy to electrical energy used by the load. Other embodiments are described and claimed.

Abstract: An embodiment provides electrical energy from a source on one side of a medium to a load on the other side of the medium, the embodiment including a first piezoelectric to generate acoustic energy in response to electrical energy from the source, and a second piezoelectric to convert the received acoustic energy to electrical energy used by the load. Other embodiments are described and claimed.

Abstract: The present invention provides a design of a horn for vibration actuators. In general a driving actuator generates vibrations and a horn amplifies the vibration amplitude where the amplification is related to the ratio between the surface area of the horn at the contact with the actuator and the tip surface. The acoustic path of existing direct horn designs is modified to adopt at least one change in direction, or fold, so as to produce a compact design Preferably there are three parallel, concentric, acoustic paths and two folds. A second embodiment has an internal horn that is concentric and internal to the actuator. A third embodiment uses a tubular horn where an electroactive stack is encircled by the horn. The device may have a hollow core for the transfer of materials from one side to the other.