Method for adjusting mattresses into an operating position and mechanism for performing said method

A mechanism for moving mattresses, beds or armchairs into an operating position comprising a bed having a frame, supported by telescopic feet positionable at various heights with respect to a floor, a lifting mechanism being comprised of extensible guides comprising staffs which are respectively slidable into said guides, said staffs having ends that converge to an articulation pin, and having opposite ends that are equipped with articulations, wherein on the frame a mattress is disposed having pivot pins project outwardly from a halfway plane of said mattress which can be coupled with articulation pins of the staffs wherein, a parallelogram has articulations which are connected to one another by a guide slot with an articulation capable of sliding in the guide slot, the staffs being articulated to the articulation pin, with the interposition of a bushing between the staffs and the articulation pin, the articulation pin extending on one side into a pulley with a return spring around which a wire is wound, fixed at its free end with the articulation, the wire at a certain height of the mattress being taut and further reducing an angle, the wire making the pulley rotate so as to turn the mattress itself.