| 摘要 |
A gantry crane comprising a pair of spaced, parallel rectangular side frames each having top and bottom members and front and rear vertical members connected to the top and bottom members, a front cross beam rigidly connected to each of the side frames at the upper front corners thereof, and a rear cross beam pivotally connected to each of the side frames at the upper rear corners thereof, each of the side frames further including diagonal braces, ground engaging drive wheels mounted on the side frames at the lower corners thereof so that as the gantry crane traverses uneven ground, the wheels maintain ground contact as the rear cross beam pivots with respect to the side frames and the front cross beam absorbs the torsional stress. |
