Inventors:
Rudy Yorio - Pompano Beach FL
Andrzej T. Guzik - Pompano Beach FL
William Boone Mullen - Coral Springs FL
Danny E. Ross - Plantation FL
Raymond C. Vivian - Clearwater FL
Assignee:
Motorola, Inc. - Schaumburg IL
International Classification:
H01L 41113
Abstract:
A piezoelectric active-mode incrementor switch system (100) includes two ratchet wheels (118, 124) that are rotationally mounted on a drive shaft (112) having a knob (102). The ratchet wheels (118, 128) form a slipping clutch with their respective drive wheels (116, 128) which are rigidly mounted to the drive shaft and mechanically loaded with spring (120). The ratchet wheels (118, 124) are mounted inversely to each other on the drive shaft (112) and make contact with their respective cantilever beams (114, 136) which each have a piezoelectric film. In operation, the switch (100) functions by mechanically stimulating the piezoelectric beams. When the knob (102) is rotated in one direction, only one of the beams (114, 136) is displaced causing a generation of an electrical charge that acts as a signal. The other beam (114 or 136) is prevented from moving and therefore its beam does not produce a signal. When the knob (102) is rotated in the opposite direction, the other beam that was previously prevented from moving is displaced causing an electrical signal to be generated by the switch.