Patent ID: 7364233
Filing Date: 2008-04-29
Classification: A47C

Abstract:
1. A chair comprising: a base on which at least one seat frame and at least one backrest frame are hinged; and a chair synchronization mechanism having at least one stiffening spring positioned directly between said base and said backrest frame, and a device to adjust the stiffness of said at least one spring including structure to move one end of said at least one spring with respect to its other end, said structure comprising at least one cam element provided to said base, said cam element being positionable to act on the end to be moved of said at least one spring, the other end of said at least one spring being directly linked to said backrest frame, wherein said structure comprises at least one connecting rod, hinged at one end to said base and engaged, at its other end, with the end to be moved of said at least one spring, and wherein said cam element is movable relative to and engages with said at least one connecting rod.