Communications: electrical – Audible indication – Percussion-type sound producer
Patent
1982-03-03
1985-01-15
Groody, James J.
Communications: electrical
Audible indication
Percussion-type sound producer
340365S, 340711, G06F 302
Patent
active
044941102
ABSTRACT:
A keyboard has tactile-feel keys (64-70) each with a grounded terminal (78) under an insulated touchable terminal (88) supplied with a square wave signal.
Touching a key increases the capacitive delay of the square wave signal on that key, so it is retarded relative to first delayed clock pulse which then resets a bistable circuit (142) to stop a counter (152), which controls scanning of the keys, at a value indentifying the touched key. This enables selection of the touched key to be verified, for example on an associated video display, whereafter the key can be pressed to actuate it, thereby establishing contact between its terminals. The resulting grounding of the touchable terminal suppresses the square wave signal, resetting another bistable circuit (172) in response to another, more delayed, clock pulse to generate a signal indicating that the desired key function is to be implemented.
REFERENCES:
patent: 3244369 (1966-04-01), Nassimbene
patent: 3750113 (1973-07-01), Cencel
patent: 3921166 (1975-11-01), Volpe
patent: 4028695 (1977-06-01), Saich
patent: 4078257 (1978-03-01), Bagley
IBM Technical Disclosure Bulletin, Mitchell et al., vol. 24, No. 5, Oct. 1981, pp. 2422-2423.
Thompson Alan D.
Wakeling Antony J.
Gaudier Dale
Groody James J.
Schlumberger Electronic (U.K.) Ltd.
LandOfFree
Keyboard modules for use in data terminals does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Keyboard modules for use in data terminals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Keyboard modules for use in data terminals will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1483791