Patent attributes
A lifting device with a head cavity in the lifting member shaped to accept a removable lifting head. The head cavity in the lifting device—e.g., the piston of a bottle jack—may be provided with threads, or may have the threads removed. A yoke fitted on the lifting head provides registration, horizontal restraint, or both against a lifted object, component, or surface to prevent sliding off the lifting head while in use. In a smooth-walled-shaft embodiment, a set of risers (spacers, adjusters, trims, or shims) serves to adjust an extension height of the shaft, elevating the lifting head with respect to the piston prior to beginning to lift the hydraulic piston.