Scissors-type lifting linkage elevator

Claim 1

A cargo-loading elevator comprising a base, a load platform, a scissors linkage for raising the platform from a lowered to a raised position and including first and second frames which are pivoted together substantially midway between their ends to form said scissors linkage, each frame including a pair of spaced arms wit braces interconnecting The arms of said pair, fixed pivots mounting one end of the first frame at a first end of the base, and fixed pivots mounting the adjacent end of the second frame to the movable platform at said first end, rollers pivoted at the opposite ends of said frames, and trackways extending longitudinally of the base and platform at the opposite end of the elevator on which the rollers travel as the platform is raised and lowered, the arms in each frame having first offset sections which are offset below the general plane of the frame, the pivots connecting said frames to form the scissors linkage passing through said offset portions below said planes, one of said frames also having a second offset portion which is offset above the plane of said frame at a point between said scissors linkage pivots and the platform, a hydraulic piston, piston rod and cylinder assembly pivotally connected at one end thereof to said second offset portion lying above said plane and at its other end to a point adjacent the base.