Multiple stage masts for lift trucks

Claim 1

A MAST ASSEMBLY FOR A LIFT TRUCK COMPRISING, FIRST, SECOND AND THIRD MAST SECTIONS, SAID SECTIONS BEING SUBSTANTIALLY THE SAME LENGTH AND DISPOSED IN NESTABLE RELATION EACH TO THE OTHER, SAID FIRST MAST SECTION BEING ATTACHED TO THE LIFT TRUCK AND EXTENDING GENERALLY VERTICALLY THEREFROM, SAID SECOND MAST SECTION MOUNTED FOR MOVEMENT LONGITUDINALLY ALONG SAID FIRST MAST SECTION, SAID THIRD MAST SECTION BEING MOUNTED FOR MOVEMENT LONGITUDINALLY ALONG SAID SECOND MAST SECTION, A LOAD CARRIAGE MOUNTED FOR MOVEMENT ALONG SAID THIRD MAST SECTION, A HOIST ASSEMBLY COMPRISING A FIRST HOIST CYLINDER HAVING A PISTON ROD, SAID HOIST CYLINDER AND PISTON ROD HAVING A LENGTH APPROXIMATELY EQUAL TO ONE-HALF THE LENGTH OF ONE OF SAID MAST SECTIONS, SAID FIRST HOIST CYLINDER BEING ATTACHED TO SAID THIRD MAST SECTION SO AS TO BE MOVABLE THEREWITH, A SECOND HOIST CYLINDER HAVING A PISTON ROD, SAID SECOND HOIST CYLINDER AND PISTON ROD HAVING A LENGTH APPROXIMATELY EQUAL TO THE LENGTH OF ONE OF SAID MAST SECTIONS, SAID SECOND HOIST CYLINDER BEING ATTACHED TO SAID THIRD MAST SECTION AND THE PISTON ROD OF SAID SECONDARY CYLINDER BEING ATTACHED TO SAID SECOND MAST SECTION, GUIDE MEANS MOUNTED ON SAID PISTON RODS, A PRIMARY FLEXIBLE MEMBER EXTENDING AROUND THE GUIDE MEANS ON THE PISTON ROD OF SAID FIRST HOIST CYLINDER AND HAVING ONE END CONNECTED TO SAID LOAD CARRIAGE AND ITS OPPOSITE END TO SAID THIRD MAST SECTION, A SECONDARY FLEXIBLE MEMBER EXTENDING AROUND THE GUIDE MEANS ON THE PISTON ROD OF SAID SECOND HOIST CYLINDER AND HAVING ONE END CONNECTED TO SAID THIRD MAST SECTION AND ITS OPPOSITE END TO SAID FIRST MAST SECTION, WHEREUPON ACTUATION OF SAID FIRST HOIST CYLINDER IS EFFECTIVE TO MOVE THE CARRIAGE ALONG SAID THIRD MAST SECTION AND ACTUATION OF SAID SECOND HOIST CYLINDER IS EFFECTIVE TO MOVE SAID SECOND AND THIRD MAST SECTIONS RELATIVELY TO EACH OTHER AND LONGITUDINALLY ALONG SAID FIRST MAST SECTION.