AIR INLET SHUT-OFF DEVICE FOR A MOTOR VEHICLE, WITH AN AUTOMATIC RETURN SYSTEM

An air inlet shut-off device for a motor vehicle having: a support frame defining a passage opening for an incoming air flow, a curtain movable between a closed position and an open position, an automatic return system for the curtain having: an elastic element which is elastic in elongation along the rolling axis of the roller shaft and secured to the latter in such a way as to be rotated and vice versa; a cylindrical slider intended to move in translation along the rolling axis and in rotation about this same axis, said slider being secured to the elastic element in such a way as to be rotated indirectly by the roller shaft, said slider including a helical groove on its outer surface, the support frame including a fixed finger configured to be inserted in said helical groove.