The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 20, 1999
Filed:
Oct. 16, 1995
Charles F Davis, Cerulean, KY (US);
Joseph V Bednar, Carrollton, TX (US);
D & B Supply, Inc., Cerulean, KY (US);
Abstract
A system for summoning a service industry worker using pulsed width modulation for remote signalling having a number of signalling switches, each connected to a transmitter. When a switch is activated, the corresponding transmitter transmits an RF carrier modulated by a lower frequency tone, turning the tone on and off in a pattern determined by a unique code assigned to the switch. A central receiver filters the signal from the transmitter and converts the tone pattern to a binary output to a computer. The computer instructs a display unit to turn on a light corresponding to the switch by sending its number in a serial bit stream of all lights that should be on. The bit stream is interpreted by circuits in the display unit using a clock signal. Upon the clock signal, the bit is sent to the appropriate register, which is used to turn on the correct light.