Full free lift mast assembly

摘要

A full free lift mast assembly having a first pair of spaced apart uprights, a second pair of spaced apart uprights mounted on the first pair of uprights and elevationally movable therealong and a carriage mounted on the second pair of uprights is provided. A first mast lift jack is connected between the first and second pairs of spaced apart uprights, and first and second interconnected carriage lift jacks are pivotally connected to and between the second pair of spaced apart uprights and the carriage. A first connecting arrangement connects a cylinder of the first and second carriage lift jacks and maintains the first and second carriage lift jacks parallel, in a preselected overlapping relationship relative to each other. Therefore, bending of the carriage lift jacks, fluid leakage, missequencing and the like have been substantially reduced. The full free lift mast assembly is particularly suited for use on a material handling vehicle.