Hinge assembly for vehicle seat back, comprises coaxial gear rings with internal and external teeth and satellite gears moving over angular course defined by limits of tooth engagement

摘要

The hinge uses parallel gears that are made up from two coaxial rings (K1,K2). The first external tooth (26) that is joined to the mobile internal tooth (22) extends over a sector smaller than the second external tooth (24). This allows the satellite gears (S1 to S4) to move along an angular course between the engagement of the two exterior teeth with the joined interior teeth (20,22). They can move between two end positions in which the fixed engagement of the internal tooth with the first external joined tooth is held while the first external tooth is released from the mobile internal tooth.