Laurence T Welsh

6469267, Oct 22, 2002

Jul 12, 2000

09/614290

Laurence M. Welsh - San Carlos CA
Leonard H. Radzilowski - Mountain View CA
Tom J. A. M. Cloots - Londerzeel, BE
Bavo A. A. Muys - Eppegem, BE
Peter J. M. Willaert - Destelbergen, BE

ELO Touchsystems, Inc. - Freemont CA

H01H 102

200512, 345173

A switch comprises two substrates coated with conductive elements opposed to each other across a gap. At least one of the conductive elements comprises an intrinsically conductive polymer. The switch completes an electrical circuit when one of substrates is pressed toward the other of the substrates and the two conductive elements touch. The polarity applied to the intrinsically conductive polymer coating is, preferably, negative. The voltage applied to the electrical circuit, is, preferably, less than five volts; more preferably, the voltage applied to the electrical circuit is less than three volts; even more preferably, the voltage applied to the electrical circuit is less than one volt.

53829093, Jan 17, 1995

Jul 30, 1993

8/100710

Michael Masia - Redwood City CA
James P. Reed - San Francisco CA
Robert S. Wasley - San Carlos CA
Larry R. Reeder - San Jose CA
Peter L. Brooks - Los Altos CA
Thomas W. Tolles - San Francisco CA
Louis M. Frank - Sunnyvale CA
Mauro Bonomi - Palo Alto CA
Ray F. Stewart - Redwood City CA
John Lahlough - San Jose CA
Laurence Welsh - Palo Alto CA

Raychem Corporation - Menlo Park CA

G01R 3108
H01B 732

324522

Detection of liquid leaks and other changes in variables is disclosed. The event causes two elongate conductors to become electrically connected at a location which is determined by the event, thus creating a system in which the connection point can be located by measuring the potential drop from one end of one of the conductors (called the locating member) to the connection point. The system comprises a balancing component so that its sensitivity is not dependent on the location of the event along an elongate path. A fixed current flows through the connection, so that the result is independent of the resistance of the connection. The locating member can be a continuous resistive wire, coated with a conductive polymer; such a locating member can form part of a sensor cable in which the elongate components of the circuit are in a wrapped configuration. Alternatively the locating member comprises a plurality of discrete resistors. The system is arranged so that only connections within a certain range of resistance will activate the system.

50159585, May 14, 1991

Jun 27, 1989

7/372179

Michael Masia - Redwood City CA
James P. Reed - San Francisco CA
Robert S. Wasley - San Carlos CA
Paul D. Hauptly - Fremont CA
Larry R. Reeder - San Jose CA
Peter L. Brooks - Los Altos CA
Thomas W. Tolles - San Francisco CA
Louis M. Frank - Sunnyvale CA
Mauro Bonomi - Palo Alto CA
Denis Wales - Fremont CA
Ray F. Stewart - Redwood City CA
John Lahlouh - Belmont CA
Laurence Welsh - Palo Alto CA

Raychem Corporation - Menlo Park CA

G01R 3108
H01B 732

324522

Detection of events, e. g. liquid leaks and other changes in varibles. The event causes two conductors to become electrically connected, and thus creating a system in which the connection point can be located by measuring the potential drop from one end of one of the conductors (called the locating member) to the connection point. Preferably a fixed current flows through the connection, so that the result is independent of the resistance of the connection. The locating member can be a continuous resistive wire, preferably coated with a conductive polymer; such a locating member can form part of a sensor cable in which the elongate components of the circuit are in a wrapped configuration, or part of a cable in which the conductors are separated by a member shaped to prevent capillary action of a liquid from connecting the conductors. Alternatively the locating member comprises a plurality of discrete resistors. Preferably the system is arranged so that the sensitivity of the system is not dependent on the location of the fault and/or is such that only connections within a certain range of resistance will activate the system.