Hinge Mechanism and Vehicle Seat Comprising Such a Mechanism, and Method for Making Such a Mechanism

Abstract

A hinge mechanism ( 6 ) for a vehicle seat, comprising: first and second frames mounted so that they can rotate relative to one another; and an annular ring comprising a cylindrical base which covers the peripheral edges of the frames, and first and second side flaps. The ring does not comprise a portion that is in contact with one of the inner faces of the frames.

1 . A hinge mechanism for a vehicle seat, comprising:
 first and second frames mounted so that they can rotate relative to one another about an axis, said frames comprising inner faces oriented inward and facing one another, outer faces oriented outward and away from each other, and circular peripheral edges distanced from the axis, and   an annular ring comprising a base which covers the peripheral edges of the frames, and first and second side flaps which cover at least a portion of each of the outer faces,   wherein the base has a cylindrical shape which extends in the direction of the axis directly between the first side flap and the second side flap, and the ring does not comprise a portion in contact with one of the inner faces of the frames.   
     
     
         2 . The hinge mechanism according to  claim 1 , wherein axial play along the direction of the axis is preserved between the first side flap and the first frame during the formation of the second side flap against the second frame. 
     
     
         3 . The hinge mechanism according to  claim 1 , wherein the second frame has a diameter greater than a diameter of the first frame, and the difference between said diameters is less than 1 mm. 
     
     
         4 . The hinge mechanism according to  claim 1 , wherein the second frame has a diameter equal to a diameter of the first frame. 
     
     
         5 . The hinge mechanism according to  claim 1   4 , wherein the peripheral edge of the second frame is in close contact with an inner face of the base ( 91 ) in order to attach the ring solidly to the second frame. 
     
     
         6 . The hinge mechanism according to  claim 1 , wherein the peripheral edge of the second frame comprises teeth which engage with the inner face of the base in order to attach the ring solidly to the second frame. 
     
     
         7 . The hinge mechanism according to  claim 1 , wherein the first side flap comprises indentations extending from said first flap in the direction of the outer face of the first frame, said indentations being greater than or equal to three in number. 
     
     
         8 . The hinge mechanism according to  claim 1 , wherein the base of the ring ( 9 ) comprises a conical inner face in order to grip the peripheral edge of the second frame radially and leave the peripheral edge of the first frame free to rotate. 
     
     
         9 . A seat of a vehicle, comprising first and second parts connected to each other by a hinge mechanism according to any of the above claims, the first frame being attached to the first part and the second frame being attached to the second part. 
     
     
         10 . The seat according to  claim 9 , wherein the first part is a frame of a seat back and the second part is a frame of a seat bottom. 
     
     
         11 . A method for making a hinge mechanism for a vehicle seat, comprising the following steps:
 a) an assembly is provided which comprises:   first and second frames able to be mounted so that they can rotate relative to one another about an axis, said frames comprising inner faces oriented inward and towards one another, outer faces oriented outward and away from each other, and circular peripheral edges distanced from the axis, and   an annular ring comprising a cylindrical base which covers the peripheral edges of the frames, and a first side flap which covers at least a portion of the outer face of the first frame,   b) a second side flap is formed by folding a portion of the ring towards the outer face of the second frame and by pressing against the outer face of the first frame.   
     
     
         12 . The method according to  claim 11 , wherein the following step is carried out between steps a) and b):
 the ring is positioned relative to the first frame with a predetermined clearance with a first tool comprising first and second surfaces, the first surface being adapted to press against the first side flap, the second surface being adapted to press against the first outer surface, and said surfaces being offset in the direction of the axis to ensure said predetermined clearance between an inner surface of the first side flap and the first outer surface of the first frame, the ring being pushed towards said first tool and said first tool being pushed towards said first frame so that said surfaces are pressing against one another.   
     
     
         13 . The method according to  claim 11 , wherein the ring is squeezed radially inward onto the peripheral edge of the second frame. 
     
     
         14 . The method according to  claim 11 , wherein step b) is carried out in at least the two following sub-steps:
 b1) the portion of the ring is folded to a first angle to form a flange sloping at said first angle, and   b2) said flange is folded to a second angle, substantially 90°, to form the second side flap facing the outer face of the second frame, the assembly being pushed towards a die by a first tool pressing against the outer face of the first frame.   
     
     
         15 . The method according to  claim 14 , wherein the first angle is between 30° and 60°, and preferably substantially equal to 45°.