| 摘要 |
<p>ROTATING POWERED STEP A powered step for use with large construction equipment such as large crawler-type tractors, mining trucks and similar vehicles that have an operator's platform located a substantial distance off the ground, and which require storage of any ladder or step within the frame perimeter and above the operator's platform to avoid damage to the step during use. The operator step, as shown, comprises a step member or operator basket mounted on a parallel linkage that is hydraulically operated, for raising and lowering. The step support surface of course remains oriented in space (horizontal), as it is raised and lowered with respect to a horizontal plane. The step includes a mounting means that automatically rotates the step member about ninety degrees between its lowered position and its raised position so that the step movement starts adjacent the side of the machine, and at the end of its raising stroke the step is positioned parallel to the longitudinal axis of the vehicle and within the frame perimeter above the operator's platform.</p> |
