Folding hard top system for convertible structure, in particular for motor vehicle

A retractable rigid roof system for an uncoverable structure comprising a roof constituted by at least two rigid panels that are movable relative to each other and relative to a passenger compartment of the structure, said at least two rigid panels including a rear first panel and a front second panel linked together by linking means arranged in such a manner that the front second panel is movable relative to the rear first panel between a closed position in which the front second panel covers the passenger compartment and an open position in which the front second panel is in a position that is substantially superposed relative to the rear first panel, the rear first panel being mounted to pivot relative to a bodywork of the structure in such a manner as to pivot together with the front second panel between a closed position in which the rear first panel covers the passenger compartment, and an open position in which the rear first panel and the front second panel are received in their substantially superposed position behind the passenger compartment, the front second panel being connected to the rear first panel via two sets of two substantially parallel auxiliary pivot arms, each set of pivot arms comprising a front arm and a rear arm, each of said arms being pivoted at a rear end to a respective rear hinge point fixed to the rear first panel and at a front end to a respective front hinge point fixed to the front second panel, the two arms in each set being arranged so as to be situated transversely outside the front second and rear first panels, means for causing respective pivot shafts of the rear ends of both said arms in both sets of auxiliary arms to pivot in one direction to open said roof system and in another direction to close said roof system.