| CPC B65H 9/002 (2013.01) [B65H 2404/1424 (2013.01); B65H 2601/272 (2013.01)] | 3 Claims |
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1. A method for aligning a sheet in a feeder of a sheet-processing machine, the method comprising:
transporting a plurality of sheets in a transport direction with one sheet following another in a sheet transport cycle;
delivering the sheet to be aligned to a sheet transport device in the transport direction by a first feed roller and a first counterpressure roller cooperating with the first feed roller, and by a second feed roller and a second counterpressure roller cooperating with the second feed roller, wherein the first and second feed rollers are commonly mounted on a slide that is movable, with the first and second feed rollers, in a direction transversely to the transport direction;
driving the first feed roller in rotation by a first motor and simultaneously driving the second feed roller in rotation by a second motor;
performing a set-down motion, wherein the first and second counterpressure rollers are set down onto the first and second feed rollers, respectively, and a lift-off motion by pivoting a support upon which the first and second counterpressure rollers are rotatably mounted, and performing the set-down motion and the lift-off motion in synchronicity with the sheet transport cycle;
in a first alignment step, aligning the sheet laterally by clamping the sheet between the first feed roller and the first counterpressure roller and between the second feed roller and the second counterpressure roller, and moving the slide on which the first feed roller and the second feed roller are mounted together with the clamped sheet in a first direction transversely to the transport direction;
in a second alignment step, after the sheet has been gripped by the sheet transport device, lifting the first counterpressure roller from the sheet on the first feed roller, and lifting the second counterpressure roller from the sheet on the second feed roller; and
in a third alignment step, subsequent to lifting the first and second counterpressure rollers from the sheet, moving the slide with the first feed roller and the second feed roller back in a second direction counter to the first direction while the sheet, which is no longer clamped between the first and second feed rollers and the respective first and second counterpressure rollers, is still present in a region between the first feed roller and the first counterpressure roller and in a region between the second feed roller and the second counterpressure roller;
during a movement of the slide in the first direction and in the second direction, moving the slide relative to the first motor and relative to the second motor.
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