Vehicle wheel anti-slip device

A vehicle wheel having an anti-slip device comprising a plurality of independently pivotable blades, a plurality of pivot shafts extending laterally from the wheel and spaced around the wheel, the blades being mounted on the respective pivot shafts, each blade comprising an active portion and a successive control portion between which portions the pivot shaft lies, control means for acting on each control portion to pivot the blade from a rest position to an operating position in which the active portion of the blade projects past the periphery of the wheel before the active portion penetrates the ground during rotation of the wheel, and a plurality of stops each defining the operating position of a respective blade by cooperation with its active portion, the mutual arrangement of the pivot shaft, the active portion, and the stop associated with each blade being such that the part of the active portion which initially penetrates the ground is ahead of the pivot shaft with respect to the direction of motion of the vehicle, the reaction of the ground urging the active portion against the stop and urging the control portion away from the control means, whereby the active portion, the stop, and the pivot shaft alone transmit to the wheel the force of penetration of the active portion into the ground thereby avoiding subjecting the control means to the force of penetration.