Patent ID: 7984902
Filing Date: 2011-07-26
Classification: B65H

Abstract:
1. A sheet feeding device, comprising: a loading portion configured to be loaded with a stack of sheets and to be movable up and down; a lifting mechanism configured to lift the loading portion in an operating state and to stop lifting the loading portion in a stopped state; a cam configured to be rotated alternately to a first rotational position for setting the lifting mechanism to the operating state and to a second rotational position for setting the lifting mechanism to the stopped state; a detecting unit having a contact portion configured to be movable up and down while contacting a top sheet of the stack on the loading portion, the detecting unit being configured to detect whether the top sheet reaches a first height based upon the movement of the contact portion and to detect whether the top sheet reaches a second height lower than the first height; and a control unit configured to stop the cam in the first rotational position until the detecting unit detects that the top sheet reaches the second height and to start rotating the cam before the detecting unit detects that the top sheet reaches the first height such that the lifting mechanism lifts the loading portion intermittently while switching between the operating state and the stopped state, wherein the control unit is further configured to stop the cam in the second rotational position in response to the detecting unit detecting that the top sheet reaches the first height.