Method and system for synchronizing items using position compensation
AssigneeBell & Howell Company
InventorAaron A. Kracht
Life of this patent
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Abstract
The present applications relates to techniques and equipment to control the alignment of cut sheets of paper that are transported in parallel in an inserting system prior to their assembly into a document and inserted into an envelope. The alignment of the parallel sheets is adjusted by commanding incremental position changes to servo drive motors used to control the position of the parallel sheets during their transport through a hold module of the inserting system.
Claims17
An inserting system configured to adjust alignment of a plurality of sheets of paper outputted from a cutter module, the inserting system comprising:
- a hold module positioned downstream from the cutter module, the hold module including:
- a plurality of parallel sheet transports for transporting the sheets of paper in parallel;
- a plurality of servo motors configured to drive each sheet transport and each servo motor coupled to an encoder configured to generate encoder pulses for each rotation of the servo motors;
- first and second photo sensors configured to detect a presence of first and second sheets at respective sheet transport entry points;
- and
- an inserter system control computer programmed to calculate an alignment adjustment of the sheets in the hold module to account for requirements of one or more modules downstream of the hold module, the system control computer configured to:
- calculate an initial alignment offset between the sheets based on a difference in encoder pulses received between a first detection of the first sheet by the first photo sensor on a first sheet transport and a detection of the second sheet by the second photo sensor on a second sheet transport,
- receive established sheet alignment requirements of the one or more modules downstream of the hold module,
- calculate an alignment correction distance, and
- control a distance that each sheet in the hold module is to be moved for each cyclic update.
A method for aligning a plurality of sheets processed in parallel by an inserter system, the method comprising steps of:
- transporting first and second sheets through parallel first and second sheet transports of a hold module of the inserter system;
- receiving photocell triggers from first and second photocells, and encoder pulse values from first and second encoders positioned at the first and second sheet transports in the hold module as the first and second sheets are transported through the hold module;
- calculating an initial alignment offset by counting a number of encoder pulses received from the first encoder from a first time at which the first sheet triggers the first photocell until a second time at which the second sheet triggers the second photocell;
- dividing an amount of alignment correction between a first servo motor associated with the first sheet transport and a second servo motor associated with the second sheet transport based on requirements of one or more subsequent modules downstream from the hold module;
- and
- driving the first servo motor to adjust a first distance moved by the first sheet in the first sheet transport for each cyclic update, and driving the second servo motor to adjust a second distance moved by the second sheet in the second sheet transport for each cyclic update,
- wherein a total number of cyclic updates sent to each servo motor results in moving the first and second sheets through the hold module while imparting an offset distance between the first and second sheets.
Dependencies are inferred from the claim text.