Overlapping document strip conveying method and apparatus

Apparatus for conveying at least two superposed strips of documents in a direction of conveyance toward a downstream workstation, each of said strips comprising a plurality of documents, each of said documents having a portion thereof which will be a leading edge upon eventual separation of said document from its strip, said strips being conveyed over one another in a direction of superposition whereby the leading edges of documents of one strip alternate in sequence in the direction of conveyance with the leading edge of documents in another strip, said apparatus comprising:

• conveying means for imparting motion to said strips in said direction of conveyance;
• separating means for separating in alternating strip fashion leading ones of said document from their respective strips;
• means for determining whether the speeds of motion of said strips are in an acceptable velocity relationship, said determining means further comprising:
• means for determining when leading ones of said documents have been separated from their respective strips and for generating a separation signal indicative thereof;
• means for generating timing pulses;
• first counter means;
• second counter means;
• counter select means for selectively enabling counting of said timing pulses by said first counter and said second counter, said counters being enabled in alternating fashion after documents are separated in alternating strip fashion from their strips, said counters being enabled to count the number of pulses generated from a point in time after a preceding document has been separated from a first of said strips until a document has been separated from a second of said strips;
• and,
• means for comparing the count in one of said counters (indicative of the number of timing pulses generated with respect to the conveyance of a just-separated from said second strip document) with the count in the other of said counters (indicative of the number of timing pulses generated with respect to the conveyance of the document previously separated from said first strip) and for generating a comparison signal indicative thereof;
• braking means capable of at least temporarily retarding the motion of at least one of said strips;
• and,
• control means responsive to said determining means for controlling said braking means whereby the motion of at least one of said strips is retarded for restoring said acceptable velocity relationship of said strips.

A method for conveying at least two superposed strips of documents in a direction of conveyance toward a downstream workstation, each of said strips comprising a plurality of documents, each of said documents having a portion thereof which will be a leading edge upon eventual separation of said document from its strip, said strips being conveyed over one another in a direction of superposition whereby the leading edges of documents of one strip alternate in sequence in the direction of conveyance with the leading edge of documents in another strip, said method comprising the steps of:

• imparting motion to said strips in said direction of conveyance;
• separating in alternating strip fashion leading ones of said document from their respective strips;
• determining whether the leading edges of documents in one of said strips are in an acceptable positional relationship in said direction of conveyance with said leading edges of documents in the other of said strips, said determining step further comprising the steps of:
• determining when leading ones of said documents have been separated from their respective strips and for generating a separation signal indicative thereof;
• using pulse generation means for generating timing pulses;
• selectively enabling counting of said timing pulses by a first counter and a second counter, said counters being enabled in alternating fashion after documents are separated in alternating strip fashion from their rows, said counters being enabled to count the number of pulses generated from a point in time after a preceding document has been separated from a first of said strips until a document has been separated from a second of said strips;
• and,
• comparing the count in one of said counters (indicative of the number of timing pulses generated with respect to the conveyance of a just-separated from said second strip document) with the count in the other of said counters (indicative of the number of timing pulses generated with respect to the conveyance of the document previously separated from said first strip) and for generating a comparison signal indicative thereof;
• using braking means capable of at least temporarily retarding the motion of at least one of said strips;
• and,
• controlling said braking means whereby the motion of at least one of said strips is retarded for urging the leading edges of documents in one of said strips into said acceptable positional relationship in said direction of conveyance with the leading edges of documents in the other of said strips.

A method for conveying at least two superposed strips of documents in a direction of conveyance toward a downstream workstation, each of said strips comprising a plurality of documents, each of said documents having a portion thereof which will be a leading edge upon eventual separation of said document from its strip, said strips being conveyed over one another in a direction of superposition whereby the leading edges of documents of one strip alternate in sequence in the direction of conveyance with the leading edge of documents in another strip, said method comprising the steps of:

• imparting motion to said strips in said direction of conveyance;
• separating in alternating strip fashion leading ones of said document from their respective strips;
• determining whether the speeds of motion of said strips are in an acceptable velocity relationship, said determining step further comprising the steps of:
• determining when leading ones of said documents have been separated from their respective strips and for generating a separation signal indicative thereof;
• using pulse generation means for generating time pulses;
• selectively enabling counting of said timing pulses by a first counter and a second counter, said counters being enabled in alternating fashion after documents are separated in alternating strip fashion from their rows, said counters being enabled to count the number of pulses generated from a point in time after a preceding document has been separated from a first of said strips until a document has been separated from a second of said strips;
• and,
• comparing the count in one of said counters (indicative of the number of timing pulses generated with respect to the conveyance of a just-separated from said second strip document) with the count in the other of said counters (indicative of the number of timing pulses generated with respect to the conveyance of the document previously separated from said first strip) and for generating a comparison signal indicative thereof;
• using braking means capable of at least temporarily retarding the motion of at least one of said strips;
• and,
• controlling said braking means whereby the motion of at least one of said strips is retarded for restoring said acceptable velocity relationship of said strips.