Patent attributes
A jack, comprising: a top plate having at least one adapter block mounted thereon and adapted to contact a load; an intermediate plate; a base plate; a first pair of actuators coupled between the base and intermediate plates; and, a second pair of actuators coupled between respective lowered portions of the intermediate plate and the top plate; wherein one of the first pair of actuators is positioned on the base plate on either side of the respective lowered portions; wherein the actuators are operable to move the top and intermediate plates between respective lowered and raised positions to thereby lower and raise the load; and, wherein a top adapter plate of the at least one adapter block is operable to slide between first and second positions across the top plate as the load is raised and lowered to maintain alignment of the top, intermediate, and base plates below the load.