Register control system and method

Claim 3

In apparatus for providing a set point signal for use in sensing register errors with respect to a moving web, means for generating encoder pulses as a function of web movement and for generating a cyclically occurring reference signal to initiate successive error-sensing cycles, scanner means for generating a scanner signal whose time of occurrence is responsive to register errors relative to said reference signal in each error-sensing cycle, and counting means including a main counter with a memory register for storing a count value controlling the count at which the main counter supplies an output signal, said counting means being operable to count encoder pulses beginning with the occurrence of one of said reference signals and to emit a set point signal which is to be time coincident with one of said scanner signals, wherein the improvement compriseS setup circuitry for operation in a setup cycle while the web has substantially a zero registration error to cause counting of encoder pulses beginning with the occurrence of a reference signal and ending with the occurrence of a scanner signal to provide an encoder count equal to the correct spacing between the reference signal and the scanner signal, and means operable during the setup cycle only for delaying the counting of encoder pulses be the main counter for a time interval corresponding to the time spacing between the occurrence of the output signal from the main counter and the set point signal in normal operation, thereby to produce a count in the main counter of the correct value for normal operation, said memory register of said main counter being automatically operable to store said count of the main counter during the setup cycle and thereafter to control the main counter in accordance with such count during normal operation where the delaying time interval is omitted.

Claim 4

In apparatus for providing a set point signal for use in sensing register errors with respect to a moving web, means for generating encoder pulses as a function of web movement and for generating a cyclically occurring reference signal to initiate successive error-sensing cycles, scanner means for generating a scanner signal whose time of occurrence is responsive to register errors relative to said reference signal in each error-sensing cycle, and counting means including a main counter with a memory register for storing a count value controlling the count at which the main counter supplies an output signal, said counting means being operable to count encoder pulses beginning with the occurrence of one of said reference signals and to emit a set point signal which is to be time coincident with one of said scanner signals, wherein the improvement compriseS setup circuitry for operation in a setup cycle while the web has substantially a zero registration error to cause counting of encoder pulses beginning with the occurrence of a reference signal and ending with the occurrence of a scanner signal to provide an encoder count equal to the correct spacing between the reference signal and the scanner signal, and means operable during the setup cycle only for delaying the counting of encoder pulses be the main counter for a time interval corresponding to the time spacing between the occurrence of the output signal from the main counter and the set point signal in normal operation, thereby to produce a count in the main counter of the correct value for normal operation, said memory register of said main counter being automatically operable to store said count of the main counter during the setup cycle and thereafter to control the main counter in accordance with such count during normal operation where the delaying time interval is omitted.

Claim 5

Apparatus according to claim 2 with said setup circuitry having a memory-set switch for selective actuation to initiate a setup during which a new count value is automatically stored in said memory register as a function of a scanner signal occurring after actuation of the memory-set switch is completed, whereby a different scanner signal may be selected from which to determine register errors.

Claim 6

Apparatus according to claim 2 wherein a mark discriminator switch is connected with said setup circuitry but is physically located adjacent said scanner means, said switch being actuatable to initiate a setup cycle with respect to a visually observed mark on the web.