| 摘要 |
<p>PURPOSE:To carry out operation for holding the attitude of a seat constant and the raising/lowering operation of an elevation leg by a simple mechanism by constituting four pairs of elevation legs from a pinion double rack mechanism and selectively switching a driving pinion in a released state and a turning drive state. CONSTITUTION:When a staircase elevation/lowering shift vehicle goes over a step difference part, a driving pinion 341 on one rack 211 side is put into released state, having the other rack 212 as a grounded axis leg. Then, a pinion 342 for drive on the rack 212 side turns in the direction of arrow A, and at the same time, a nut 31 revolves. At this time, the pinion 342 drives a body 1 in the L-rising direction for the rack 212, and the nut 31 drives a ball screw 24 and a pinion 22 in the L-rise direction for the body 1. Accordingly, in the drive, the rack 211 is 4L-raised for the rack 212, and the wheel 21b at the lower edge of the rack 211 shifts to the next step S in the step difference part. Further, when the rack 212 is raised, having the rack 211 as the axis leg on the step S, the pinion 342 is put into released state, and the pinion 341 turns in the direction of arrow B, and at the same time, the nut 31 is revolved to raise the body 1.</p> |
