US Patent 7503606 Lifting assembly

In one aspect of the present invention, a lifting assembly has a frame structure with a translatable support element. The support element has a load-bearing surface and a screw-form. The screw-form is threadedly connected to a gear which is in mechanical communication with a power source, which may be an electric motor. The load-bearing surface is fixed to a shaft of the translatable support element and at least a portion of the load-bearing surface is angularly oriented with respect to the shaft. A guide with at least one end fixed to the frame structure is adapted to adjust the rotational orientation of the load-bearing surface.