Patent ID: 8167296
Filing Date: 2012-05-01
Classification: B65H

Abstract:
1. An image forming apparatus having a sheet feeding apparatus for blowing air against sheets stacked on a tray, loosening the sheets, and feeding a loosened sheet toward an image forming unit, comprising: an air blowing mechanism which is constructed by combining a plurality of fans serially so that air blown out from an upstream positioned fan among the plurality of fans in a flow of the air is drawn by a downstream positioned fan among the plurality of fans in the flow of the air in order to blow air against the sheets stacked on the tray; a driving unit which moves the tray upward and downward; a sheet presence/absence detecting sensor which detects presence/absence of the sheet on the tray; a lower position detecting sensor which detects the tray at a lower position; and a control unit which performs a rotational speed control which adjusts the plurality of fans of the air blowing mechanism, wherein the control unit controls the driving unit to lower the tray to the lower position based on the lower position detecting sensor, the control unit performs the rotational speed control based on a detection by the sheet presence/absence detecting sensor indicating that a no-sheet state on the tray is detected and a detection by the lower position detecting sensor indicating that the tray moved by the driving unit is at the lower position, and the control unit controls rotational speeds of at least two of the plurality of fans individually so as to adjust the rotational speeds of the plurality of fans to be within target rotational speed ranges which have been set for each of the plurality of fans.