| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve paper feeding performance by providing a paper feeding head touching the top part of a stack of sheet, operating a sheet supporting body according to an output from a sensor when a sheet is fed from the stack, and maintaining the proper stack height. SOLUTION: In a sheet feeder feeding a print sheet to a transfer unit, a feeding head 50 including a light pressure roll 53 touching the uppermost part sheet in a stack 54 is provided, and a sheet in the stack 54 is slightly pushed into a nip constructed of a feeding roll 52 and a speed reducing roll 51. In this process, the light pressure roll 53 is translated downward according to consumption of the sheets in the stack 54, and a sensor flag 150 is turned, and then, a sensor 160 is opened. On the basis of the output from the sensor 160, an elevator mechanism is operated so as to lift the stack 54, and when the sensor 160 is closed, the elevator motion is stopped so as to hold a proper stack height.</p> |
