Patent ID: 6786170
Filing Date: 2004-09-07
Classification: B63B

Abstract:
A lifting device for a boat, the lifting device comprising:a first platform; a plurality of linkage members, the plurality of linkage members configured to form at least two four-bar linkage assemblies, each four-bar linkage assembly having a first end pivotally attached to the first platform and a second end pivotally attached to a boat, wherein each four-bar linkage assembly forms two parallelogram linkages connected to each side of the first platform; at least one hydraulic cylinder, said cylinder having a first end and second end, the first end being pivotally connectable to the structure of a boat and the second end pivotally attached to at least one linkage member; a fluid device in communication with the hydraulic cylinders; and at least one load sharing member configured to span and connect to at least two of the four-bar linkages together to prevent uneven or tilted motion of the first platform.