| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the application of excessive force to a sheet feeder and the like so as to prevent the device from overturning when the rotation of a wheel in a caster in the lower part of the sheet feeder is fixed completely. SOLUTION: In this device, a projection strap part 56 is formed in the vicinity of a fitting part for an axle 52 of a rotational frame 51 arranged in the lower part of a sheet feeder freely rotationally, and in a lever 54, which is supported in the axle 52 freely rotationally, a recess groove which can be fitted around the projection strap part 56 in the frame 51, is formed on one face, while the other face is used as a flange part 52a for the axle 52, so that a wheel can be freely rotated when the projection bar part 56 and the recess groove are fitted to each other. When the projection strap part 56 and the recess groove are not fitted to each other, the side face of the wheel is pressed by means of the one face via the vicinity of the projection bar part 56 in the frame 51, so that the rotation of the wheel by torque of a predetermined value or less is prohibited, while the rotation of the wheel is allowed when the torque exceeds the predetermined value, so that the sheet feeder and the like can be prevented from overturning.</p> |
