Patent ID: 7070171

Claim:
Suspension and hoisting system for a load support, applied towards the two opposite ends of said load support, said load support being suspended by at least four suspension reaches comprised of at least two suspension elements, each suspension element being suspended towards one of said support ends from a fixed point and towards the other support end from a driven member of a lifting means by being reeved around circular suspension element deflection supports which are in integral rotation with the suspension elements and are mounted on two parallel shafts, each end of the load support having one of said shafts mounted towards said respective end, and the circular supports located towards the same end of the load support being mounted on one and the same shaft, each suspension element being connected to its associated lifting means at the end of the load support opposite the end of the load support at which the other suspension element is connected to the other lifting means, that at least one of the suspension elements is reeved successively around at least two coaxial circular supports towards each load support end to follow such a path that, on at least one of the end shafts, at least one circular support associated with said one suspension element rotates in the same direction as at least one coaxial circular support associated with the other suspension element, under identical action of the two lifting means related to the suspension elements, whereas a torque of equal intensity and opposite direction is applied to said two circular supports, respectively, when their common shaft is constrained downwardly by a same force independently of the action of the lifting means, and that said two circular supports are interlocked, whereby the effect of said force is substantially cancelled without thereby affecting the action of the lifting means on the circular supports through the intermediary of the suspension elements.