| 摘要 |
The hitch comprises a support and a fifth wheel hitch plate above the support, having opposite lateral sides and a fore to aft longitudinal axis. A linkage between the support and fifth wheel hitch plate at each lateral side allows the fifth wheel hitch plate to move vertically up or down with respect to the support. A pair of cam followers are on each linkage. A pair of wedging cams on the support are positioned to cooperatively engage the cam followers. Each wedging cam comprises a pair of slidably interconnected lower and upper wedges. A pair of power actuators mounted on the support are connected to the wedging cams to extend and sequentially shift the lower wedges and then the upper wedges into elevating engagement with the cam followers to raise the fifth wheel plate relative to the support, and to retract and sequentially shift the upper wedges and then the lower wedges to lower the fifth wheel plate relative to the support. |
