Document feeding systems

Claim 2

Document feeding apparatus including means operative to feed a succession of documents one by one along a feeding path; sensing means operable to generate a first signal in response to the passage of each document past a fixed point in the feeding path; timing means having a plurality of timing signal output lines and being operative to generate a single timing signal on each of said output lines for each passage of a document past the sensing means, each such timing signal occurring during a different predetermined time interval relative to a selected document timing; gating means having gating output lines corresponding to said timing signal output lines and responsive to said first signal and said timing signals to generate for each document a single pulse of predetermined duration on one of the gating output lines determined by the timing coincidence of the first signal with one of the timing signals; pulse integrating means, one connected to each of the gating output lines and responsive to the pulses thereon to generate an output signal the magnitude of which is representative of the number of pulses received by the integrating means over a predetermined time period; and visual indicating means one connected to each integrating means and responsive to the output signal therefrom to provide an indication dependent on the magnitude of said output signal.

Claim 3

Document feeding apparatus as set forth in claim 1 in which one of said gating means generates pulses of half the duration of the pulses generated by the remainder of the gating means.

Claim 4

Document feeding apparatus as set forth in claim 1, having means for generating a train of pulses in synchronism with the cycle of operation of the document feeding means; a pulse counter responsive to said train of pulses; a plurality of gates controlled by the counter and operative to produce output pulses at selected times within the said cycle; and a plurality of two state devices, each responsive to a pair of said output pulses, such that a different one of the devices is in a predetermined state for the duration of each of said different time increments.

Claim 5

Document feeding apparatus as set forth in claim 3, having a plurality of AND gates, each responsive to said first signals and to state representing signals of one of said two state devices to generate an output signal for each of said first signals which occurs in a particular time increment.

Claim 6

Document feeding apparatus as set forth in claim 4, having a plurality of monostable devices, each responsive to output signals from one of said AND gates to apply pulses of predetermined amplitude and duration to a pulse integrating circuit.

Claim 7

Document feeding apparatus as set forth in claim 1, having reference voltage sources; voltage comparison devices operable to compare the output signals with said reference voltages; and two sTate devices settable in accordance with the result of the comparisons at predetermined sampling times.

Claim 8

Document feeding apparatus as set forth in claim 6, having a logical gating circuit interconnecting the said two state devices and said driving means, and so arranged that the driving means may be controlled by one of said two state devices, and by one of said two state devices in conjunction with at least one other of said two state devices.

Claim 9

Document feeding apparatus as set forth in claim 7, having a constantly rotating vacuum drum operable to feed the documents one by one from a stack of documents; a contrarotating separator roller positioned adjacent to the surface of said drum; and means operable to adjust the spacing between the separator roller and the surface of the drum.

Claim 10

Document feeding apparatus as set forth in claim 1, having means for supporting a stack of documents; a rotatable drum positioned adjacent a face of the stack; selectively operable means for applying vacuum to the drum to cause it to extract a document from the stack; and a separator roller positioned adjacent to the drum to engage a document extracted from the stack; and means for rotating the roller in a direction which tends to move such document back into the stack.

Claim 11

Document feeding apparatus including means operative to feed a succession of documents one by one along a feeding path; feed adjustment means operable to control the feeding of the documents to vary the timing thereof; sensing means operable to generate a first signal in response to the passage of each document past a fixed point in the feeding path; timing means having a plurality of timing signal output lines and being operative to generate a single timing signal on each of the said output lines for each passage of a document past the sensing means, each such timing signal occurring during a different predetermined time interval relative to a selected document timing; gating means having gating output lines corresponding to said timing signal output lines and responsive to said first signal and said timing signals to generate for each document a single pulse of predetermined duration on one of the gating output lines determined by the timing coincidence of the first signal with one of the timing signals; pulse integrating means, one connected to each of the gating output lines and responsive to the pulses thereon to generate an output signal the magnitude of which is representative of the number of pulses received by the integrating means over a predetermined time period; driving means operatively coupled to said feed adjusting means; and means controlled by the output signals of the integrating means and effective to energize the driving means to operate the adjusting means to provide a desired document timing.

Claim 12

Document feeding apparatus including means operative to feed a succession of documents one by one along a feeding path; feed adjustment means operable to control the feeding of the documents to vary the timing thereof; sensing means operable to generate a first signal in response to the passage of each document past a fixed point in the feeding path; timing means having a plurality of timing signal output lines and being operative to generate a single timing signal on each of the said output lines for each passage of a document past the sensing means, each such timing signal occurring during a different predetermined time interval relative to a selected document timing; gating means having gating output lines corresponding to said timing signal output lines and responsive to said first signal and said timing signals to generate for each document a single pulse of predetermined duration on one of the gating output lines determined by the timing coincidence of the first signal with one of the timing signals; pulse integrating means, one connected to each of the gating output lines and responsive to the pulses thereon to generate an output signal the magnitude of which is representative of the number of pulses received by the integrating means over a predetermined time period; driving means operatively coupled to said feed adjusting means; and means controlled by the output signals of the integrating means and effective to energize the driving means to operate the adjusting means to provide a desired document timing.

Claim 13

Document feeding apparatus as set forth in claim 10, having means for generating a train of pulses in synchronism with the cycle of operation of the document feeding means; a pulse counter responsive to said train of pulses; a plurality of gates controlled by the counter and operative to produce output pulses at selected times within the said cycle; and a plurality of two state devices, each responsive to a pair of said output pulses such that a different one of the devices is in a predetermined state for the duration of each of said different time increments.

Claim 14

Document feeding apparatus as set forth in claim 11, having a plurality of AND gates, each responsive to said first signals and to state representing signals of one of said two state devices to generate an output signal for each of said first signals which occurs in a particular time increment.

Claim 15

Document feeding apparatus as set forth in claim 12, having a plurality of monostable devices, each responsive to output signals from one of said AND gates to apply pulses of predetermined amplitude and duration to a pulse integrating circuit.

Claim 16

Document feeding apparatus as set forth in claim 10, having reference voltage sourceS; voltage comparison devices operable to compare the output signals with said reference voltages; and two state devices settable in accordance with the result of comparisons at predetermined sampling times.

Claim 17

Document feeding apparatus as set forth in claim 14, having a logical gating circuit interconnecting the said two state devices and said driving means, and so arranged that the driving means may be controlled by one of said two state devices, and by one of said two state devices in conjunction with at least one other of said two state devices.

Claim 18

Document feeding apparatus as set forth in claim 15, having a constantly rotating vacuum drum operable to feed the documents one by one from a stack of documents; a contrarotating separator roller positioned adjacent to the surface of said drum; and means operable to adjust the spacing between the separator roller and the surface of the drum.

Claim 19

Document feeding apparatus as set forth in claim 10, having means for supporting a stack of documents; a rotatable drum positioned adjacent a face of the stack; selectively operable means for applying vacuum to the drum to cause it to extract a document from the stack; and a separator roller positioned adjacent to the drum to engage a document extracted from the stack; and means for rotating the roller in a direction which tends to move such document back into the stack.