Articulation for a seat back comprising a composite bearing plate

Claim 1

An articulation for a seat back comprising a fixed flange (2) having a lower recess, and a mobile flange (1) adjacent said fixed flange, a slidable composite bearing plate (15) and a cam (5) moveably mounted within the lower recess (3) and said mobile flange (1) being also provided with a recess (8) in registration with the lower recess (3) and being larger than said lower recess (3), said fixed and mobile flanges being mounted on an articulation axis (0) above said movable flange with said fixed and mobile flanges being alternatively movable and fixed with respect to one another by means of said slidable composite bearing plate (15), a drive shaft (6) for rotating said cam (5) to control displacement of said slidable composite bearing plate, said cam being provided with a stepped portion (11) and a nose (10), said slidable bearing plate (15) being guided by parallel walls (3a, 3b) of the lower recess (3) and being formed of first and second parts (15a, 15b) bearing together along a straight line (D1), said first and second parts of said bearing plate having lower toothings (15e, 15f) cooperating with a corresponding toothing (7) of said mobile flange (1), the lower toothing (15e) of said first part substantially fully engaging said corresponding toothing (7) while the lower toothing (15f) of said second part (15b) extends only partly within said corresponding toothing (7), whereby a degree of play exists to provide compensation when the stepped portion (11) pushes said second part (15b) of said slidable composite bearing plate (15).