Patent ID: 6981822

Claim:
A jacking system comprising a mobile, marine-based platform, a plurality of supporting legs for said mobile, marine-based platform and means for providing relative motion between the mobile, marine-based platform and the plurality of supporting legs, each of said plurality of supporting legs including a leg chord comprising a column with a toothed rack welded on one side of the column, the means for providing relative motion between the mobile, marine-based platform and the plurality of supporting legs comprising: a plurality of continuous linear motion motors, with at least one continuous linear motion motor being engaged with the toothed rack of the leg chord of each of the supporting legs, each continuous linear motion motor comprising at least three piston/cylinder units, each of the at least three piston/cylinder units having an extendable and retractable piston and a toothed rack engagement member driven by its piston and an engagement/disengagement means for engaging and disengaging the toothed rack engagement member with the toothed rack; and a source of hydraulic pressure for operating the continuous linear motion motors; and control means for operating said plurality of continuous linear motion motors by operating a portion of the engagement/disengagement means of each of said continuous linear motion motors and engaging a portion of the toothed rack engagement members of each of said continuous linear motion motors with the toothed racks, and operating said engaged portion of said continuous linear motion motors to provide said continuous relative motion while operating at least one of the engagement/disengagement means of each of said continuous linear motion motors and disengaging at least one toothed rack engagement member of each of said continuous linear motion motors and operating the disengaged one of the continuous linear motion motors to reposition the disengaged toothed rack engagement member for re-engagement with the toothed rack and providing said continuous relative motion.