Control logic for trouble detection and recovery

Claim 2

In a copier/duplicator apparatus wherein differentiated copy counting and indicating means are provided which includes a first meter for indicating copy counts of the copy run up to a predetermined number and a second meter for indicating copy counts of the copy run above said predetermined number and wherein means are provided to detect out-of-supply condition actually occurring during a copy run and interrupt the operation of the apparatus and counting and indicating means and put them into an interrupt mode, whereby the supply can be replenished and then copying counting and indicating operation can be resumed to complete the copy run, and the improvement which comprises: means for detecting the out-of-supply condition artificially induced and generating an out-of supply signal, means for determining from the nature of the out-of-supply signal whether it is for the acTual condition or for an artifically induced condition and generating a first signal indicative of the actual condition and a second signal indicative of the artificial condition, means responsive to the first signal for putting the apparatus and the counting and indicating means into the interrupt mode, and means responsive to the second signal for terminating the copy run, whereby an attempt to tamper with the differentiated counting means by introducing artificially induced out-of-supply condition is circumvented.

Claim 3

A copier/duplicator apparatus according to claim 1, including means for detecting jam condition and providing an interrupt signal, means responsive to said interrupt signal and putting apparatus and counting and indicating means into the interrupt mode, means for detecting removal of the jam condition that produced the interruption and enabling said apparatus and said counting and indicating means to complete the copy run.

Claim 4

The apparatus according to claim 2 including scanning means operating in successive cycles at said regular time interval, means responsive to the operation of said scanning means for generating a train of count pulses, said counting and indicating means counting said train of count pulses and indicating the count of the pulses as the counts of the copies being made by said apparatus, said scanning and count pulse generating means stopping in response to said jam signal, said pulse generating means providing one more pulse than the number of copies actually made by said apparatus, and means for inhibiting the application of the first pulse of the train of count pulses after the apparatus resumes its copy run operation, whereby the copy count indicated by said indicating means correspond to the actual number of copies made by the apparatus.

Claim 5

The apparatus according to claim 1, including means for detecting the failure of a transfer sheet from detacking from the image surface of the apparatus and generating said interrupt signal.

Claim 6

The apparatus according to claim 2, including means for detecting out of supply condition of the transfer sheets and providing said interrupt signal.

Claim 7

The apparatus according to claim 3, including safety interlock for the apparatus, means responsive to the opening of said interlock for removing power supply for the apparatus for safety and removing jammed transfer sheet, said means for resuming the copy run includes a coincidence gate which responds to a command signal to resume the copying operation only after said interlock is opened, jam removed, and then said interlock is closed.

Claim 8

The apparatus according to claim 6, including means for de-energizing said counting and indicating means when said interlock is opened in the absence of the interrupt signal.

Claim 9

The apparatus according to claim 1, including means for setting said apparatus to make a given number of copies in a copy run, said determining means includes a first coincidence gate, a second coincidence gate, means for applying the out of article supply signal to said first and second coincidence gates, means for generating and applying a first train of pulses to said first coincidence gate wherein said first pulse train is synchronized to occur in succession at the rate at which the articles are fed and wherein the pulses of the first pulse train are timed so that when the out-of-supply condition actually occurs and is detected, one of the pulses coincide at least in part with the out-of-supply signal occurring in response to the actual out-of-supply condition, and means for generating and applying a second train of pulses to said second coincidence gate wherein said second pulse train is synchronized to the rate at which the articles are fed but time displaced with respect to said first pulse train so that said second pulse train do not overlap with said first pulse train and wherein the pulses of the second pulse train are timed so that when the artifically induced out-of-supply condition occurs and is detected, one of the pulses of the second pulse train coincide at least in part with the out-of-supply signal induced artificially, whereby said first coincidence gate detects the out of supply signal indicative of the actual condition and said second coincidence gate detects artifically induced condition.

Claim 10

The apparatus according to claim 8, including means responsive to the output of said first coincidence gate for interrupting the operation of the machine so that the operation can be restarted after the articles are replenished, means responsive to the output of said second coincidence gate for stopping the operation of the machine.

Claim 11

The apparatus according to claim 9, said second pulse train generating means is adopted to generate pulses having pulse width which is substantially wider than that of the first pulse train for enhancing the discrimination capability of said coincidence gates between the actual and artifically induced out-of-supply condition signals.

Claim 12

The apparatus according to claim 10, including a tray N for holding a supply of transfer sheets, said tray being positioned at a first location from which the sheets are fed automatically, and wherein said tray can be moved to a second position to be filled with the supply, said sensing means being positioned to detect the paper being fed and is adapted to generate the out-of-supply signal when the last sheet of the supply is run out, and said sensing means also detecting the moving of said paper tray from said first position to said second position while the copy run of the copier/duplicator is in progress and generating the artifically induced out-of-supply signal.