Title:
PIEZOELECTRIC VIBRATIONAL AND ACOUSTIC ALERT FOR A PERSONAL COMMUNICATION DEVICE
Document Type and Number:
WIPO Patent Application WO2000001131
Kind Code:
A9
Abstract:
An alert apparatus for a personal communication device that includes a piezoelectric wafer positioned within the personal communication device; an alternating current input line coupled at the two sides of the wafer where polarity is recognized; and a switch coupled to the alternating current input line, operative to switch the alternating current on the alternating current input line at least between an alternating current having a first frequency and an alternating current having a second frequency. The first frequency is sufficiently high so as to cause the wafer to vibrate at a resulting frequency that produces a sound perceptible by a human ear, and the second frequency is sufficiently low so as to cause the wafer to vibrate at a resulting frequency that produces a vibration readily felt by a holder of the personal communication device.
Inventors:
DENHARDT GERALD A
JANG SEGON
BALEIN RIZZA
JANG SEGON
BALEIN RIZZA
Application Number:
PCT/US1999/014469
Publication Date:
March 30, 2000
Filing Date:
June 25, 1999
Export Citation:
Assignee:
PROJECTS UNLIMITED INC (US)
International Classes:
H04M19/04; (IPC1-7): H04M/
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