Abstract: Cost effective connectors of high bending stiffness for making high-performance piezoelectric actuators and derivative devices are disclosed. In one embodiment, the connector has circumferentially alternating recesses of circular cross-section which can be cost-effectively machined out with conventional machining techniques. The circular recesses can be adopted to house circular or non-circular cross-sectioned piezoelectric active elements to make cost effective 2-level (2×) piezoelectric displacement actuators. In another embodiment, the non-circular cross-sectioned recesses in the connector include suitable wall openings to enable said recesses to be machined out cost effectively via conventional machining techniques, or via reduced use of non-conventional machining techniques. Additional stiffening mechanisms can be added to minimize the bending displacement of the base of recesses when desired.
Abstract: The present invention provides a transverse width mode for sound and ultrasound generation and reception. The transverse width mode can be combined with conventional longitudinal or transverse mode to make sonic and ultrasonic transducers and/or arrays of multiple resonant modes, a broadband coupled mode or their combinations. Due to its half-wavelength resonance nature, when the transverse width mode is designed to operate with suitable head mass and/or matching layers, ultra broadband transducers of moderate to high sound pressure level can be realized. With active materials having low transverse sound velocities, the transverse dimensions of each transducer element can be kept about or smaller than half the wavelengths of sounds in water and human tissues, making the transverse width mode highly suited for various array designs and operations.
Abstract: An accelerometer comprises an elastic substrate beam having a first end and a second end and having upper and lower surfaces; supports to support the first and second ends of the substrate beam; sensing elements comprising piezoelectric material bonded onto the upper, lower or both the upper and lower surfaces of the substrate beam; and force applying elements for applying forces at two locations between the first and second ends. The substrate beam and the piezoelectric materials operate in a four-point bending configuration. Optionally the first and second ends of the substrate beam are formed by bending the substrate beam to reduce the physical dimensions of the device.