Chair with a pivoting backrest

Claim 1

A chair comprising a basic frame, a seat supported by the basic frame, a backrest and a support frame for supporting the backrest, the support frame being connected to the basic frame and the backrest being articulated thereto about a transverse axis so as to be movable between a substantially erect position and a pivoted-back position, resilient means being interposed between the backrest and its support frame in order to bias the backrest towards its erect position, wherein the support frame for supporting the backrest comprises a pair of lateral supporting limbs each of which has one end connected to the basic frame and the opposite end articulated to the backrest about the aforesaid transverse axis in an intermediate region relative to the height of the backrest, the supporting limbs being disposed behind the backrest so that the lower portion of the backrest bears against them when the backrest is in the erect position and wherein the backrest is a single body of synthetic material and the resilient means is comprised of at least one horizontally extending resilient leaf having a free end, and constituting an integral part of the backrest situated below the transverse axis and bearing on a rear surface of a respective supporting limb so as to oppose the pivoting of the backrest towards its pivoted-back position.