B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
B66F3/00—Devices, e.g. jacks, adapted for uninterrupted lifting of loads
B66F3/08—Devices, e.g. jacks, adapted for uninterrupted lifting of loads screw operated
B66F3/20—Devices, e.g. jacks, adapted for uninterrupted lifting of loads screw operated actuated through multiple or change-speed gearings
B—PERFORMING OPERATIONS; TRANSPORTING
B66—HOISTING; LIFTING; HAULING
B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
B66F3/00—Devices, e.g. jacks, adapted for uninterrupted lifting of loads
B66F3/08—Devices, e.g. jacks, adapted for uninterrupted lifting of loads screw operated
B66F3/10—Devices, e.g. jacks, adapted for uninterrupted lifting of loads screw operated with telescopic sleeves
B—PERFORMING OPERATIONS; TRANSPORTING
B66—HOISTING; LIFTING; HAULING
B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
B66F3/00—Devices, e.g. jacks, adapted for uninterrupted lifting of loads
B66F3/44—Devices, e.g. jacks, adapted for uninterrupted lifting of loads with self-contained electric driving motors