REGISTRATION CORRECTION FOR ROTATING DRUMS
Original Publication Date: 1978-Dec-31
Included in the Prior Art Database: 2004-Mar-31
Xerox Disclosure Journal
In high speed, xerographic printers utilizing a rotating character drum, a non-synchronism may exist between the "regmark" pulses which occur several times per revolution of the xerographic drum and "linestart" pulses which occur once per revolution of the character drum. To correct any non-synchronism, the detected linestart period is split into a convenient number of time segments by a 1/N pulse generator 4 which is coupled through an AND gate 6 to a counter 8. A correction D/A function decoder 10 coupled to the counter stages supplies a correction signal to a correction pulse generator 12 which supplies a control signal to the drive circuit 14 of the synchronous motor 16 driving the character drum 18. The xerographic drum 20 is also driven by a synchronous motor 22.