Other

The Whitaker Corporation

Pennwalt Corporation

Atochem North America, Inc.

Joseph V Chatigny

Minoru Toda

Kyung T Park

Peter F Radice

Mitchell L Thompson

Kumar Ogale

Peter R Smith

Lewis F Brown

Donald L Halvorsen

Joseph F Yaskowski

A touch sensitive switch is fabricated from a substrate having a touch region on a first surface and a piezoelectric element on a second surface of the substrate. The piezoelectric element is driven by a signal configured so that an ultrasonic wave generated by the element is transmitted into the substrate and is reflected back and forth into the substrate at both surfaces. A touch changes the reflectivity at the first surface, and influences the impedance of the transducer assembly which is comprised of the piezoelectric element and the substrate.

Reflective mode ultrasonic touch sensitive switch

A traffic sensor including piezoelectric sensors having different polarities in different lanes of the roadway so that traffic data for different lanes of a roadway may be discriminated from the polarity of the received signal(s). Preferably, the piezoelectric sensors are formed by splicing oppositely polarized piezoelectric cables or films, by changing the applied electric field during manufacture so that adjacent portions of a piezoelectric cable or film have different polarities, or by applying an electric field of a reversed polarity to respective longitudinal sections of a piezoelectric film. Traffic data from up to 8 different lanes of traffic may be discriminated using only two piezoelectric sensors in accordance with the invention by providing unique combinations of output polarities for deflections of the piezoelectric sensors in the different lanes. In order to simplify installation, such piezoelectric sensors may be disposed in parallel within the same housing or concentrically within the same cable.

Traffic sensor having piezoelectric sensors which distinguish lanes

A method of forming a laminated piezoelectric structure is disclosed wherein a plurality of polarized piezoelectric films of vinylidene fluoride and trifluoroethylene are solvent welded together. The solvent welding solution comprises a copolymer of vinylidene fluoride and trifluoroethylene and a suitable solvent. The transducers produced from such a laminated structure are also disclosed.

Laminated piezoelectric structure and process of forming the same

A penetration sensor is disclosed which contains first and second transducers sandwiched around a layer which capacitively isolates the individual transducers. This sensing arrangement allows for the operational state of the sensor to be tested by applying an interrogation signal to each of the transducers.

Penetration sensor

Growing community of inventors

Wayne, PA, United States of America

Joseph V Chatigny