Patent ID: 8152159
Filing Date: 2012-04-10
Classification: B65H

Abstract:
1. A sheet feeding device, comprising: a sheet feeding cassette including a sheet accommodating portion that accommodates a sheet stack; a main body portion to which the sheet feeding cassette is attached; a sheet carrying plate that is provided within the sheet accommodating portion and stacks the sheet stack thereon; a pickup roller that has a cylindrical periphery disposed for contacting an upper face of the sheet stack and for dispatching a sheet on an uppermost layer of the sheet stack; an elevator mechanism that displaces the sheet carrying plate between a sheet feeding position in which the upper face of the sheet stack contacts the pickup roller, and a separating position in which the upper face of the sheet stack separates from the pickup roller by a predetermined distance; and a controller that controls an operation of the elevator mechanism while the sheet feeding cassette remains attached to the main body portion such that the sheet carrying plate is lowered from the sheet feeding position to the separating position after passage of a first predetermined time between completion of a preceding sheet feeding operation for feeding a sheet located in the sheet feeding position and initiation of a subsequent sheet feeding operation, thereby preventing contact between the pickup roller and the sheet on the uppermost layer of the sheet stack for time periods in excess of the first predetermined time, wherein the controller, in controlling the operation of the elevator mechanism, causes a lowering of the sheet carrying plate from the sheet feeding position for a second predetermined time period sufficient for the sheet carrying plate to reach the separating position so that the upper face of the sheet stack is separated from the pickup roller by the predetermined distance.