Patent ID: 7357387
Filing Date: 2008-04-15
Classification: B65H

Abstract:
1. A sheet feed device comprising: a sheet accommodating unit for accommodating a plurality of cut sheets in a stacked condition; a sheet feed roller that feeds a cut sheet accommodated in the sheet accommodating unit, the cut sheet having a leading edge and a trailing edge defined in relation to a sheet feed direction in which the cut sheet is fed by the sheet feed roller; a trailing edge detector that detects the trailing edge of the cut sheet and outputs a detection signal indicative of the detection of the trailing edge; and a control unit that determines a timing at which a subsequent cut sheet is fed out by the sheet feed roller based on the detection, wherein the trailing edge detector comprises a conversion mechanism that converts movement of the cut sheet into rotations, wherein the sheet feed roller is a sector roller having a rotational shaft to be rotatable with the sector roller, and wherein the trailing edge detector comprises a collar shaft, a collar fixedly attached to the collar shaft to be rotatable with the collar shaft, a disk coaxially attached to the collar shaft, and a rotation sensor that detects rotations of the disk, wherein the sector roller feeds the cut sheet during a first phase of one rotation and does not feed the cut sheet during a second phase of one rotation, and the collar rotates during the second phase and does not rotate during the first phase, the detection signal being generated when the rotation sensor no longer detects the rotations of the disk.