SHEET FEEDER, IMAGE FORMATION APPARATUS AND SHEET CENTERING CONTROL METHOD

摘要

PROBLEM TO BE SOLVED: To obtain stable printing quality by enabling an image to be printed on a long sheet with high positional accuracy.SOLUTION: A control unit 75 detects ends of a printing object medium (long sheet) 16a by end sensors 18a and 18b when a sheet feeding roll 16 is attached to a long sheet supply part 15, specifies the center of the printing object medium 16a from the positions of the end sensors 18a and 18b, and matches the center position of the printing object medium (long sheet) 16a to the center position (of a conveyance path) of a printer body 30 in design by moving the sheet feeding roll 16 in the sheet width direction. The control unit 75 detects skew of the printing object medium (long sheet) 16a from positional deviations of ends Ea and Eb of the printing object medium (long sheet) 16a detected by the end sensors 18a and 18b, and cancels the skew by moving the sheet feeding roll 16 in the sheet width direction.SELECTED DRAWING: Figure 1