| 摘要 |
A straddle tractor of variable tractor width and utilizable on sloping ground, intended especially for carrying or hauling a machine for agricultural or public works, comprises four upright members having wheels articulated on their lower extremities and which are rigidly fixed together two by two by cross-members in order to form two rigid lateral flanks coupled to each other by at least one upper arm articulated on the said flanks in such manner that each flank is capable of pivoting with respect to the said arm about a horizontal axis, each of the two lateral flanks being further attached to the upper arm by means of a member of variable length articulated both on the arm and on the flank considered. Each of the members of variable length is constituted by an endless screw engaged in a tubular nut and capable of rotating with respect to the said nut by the action of driving means having two directions of rotation, transmission means fixed to the upper arm and comprising a device for reversing the direction of operation, being provided in order to transmit the movement of rotation to both the two rotating screws and permitting the direction of rotation of one screw to be reversed with respect to the other. |
