Patent ID: 6024406
Filing Date: 2000-02-15
Classification: B60N

Abstract:
A vehicle seat comprising a seat-back surmounted by a headrest and provided with a strength-member supporting padding, said seat-back having a front face designed to bear against the back of a passenger, the strength-member of the seat-back being made up of two portions that are movable one relative to the other, namely firstly a lower portion and secondly an upper portion carrying the head-rest, said upper portion being pivotally mounted on the lower portion to pivot about an axis of rotation between first and second angular positions in which it is respectively inclined as far rearwards and as far forwards as it will go relative to the lower portion, the front face of the seat-back itself having two superposed regions, namely a lower region and an upper region which are secured respectively to the lower portion and to the upper portion of the seat-back strength-member, the upper portion of the seat-back strength-member having a thrust member located in the seat-back below the axis of rotation of said upper portion so that in the event of the vehicle being subjected to an impact from behind, the upper portion of the seat-back strength-member is urged towards the second angular position, the upper and lower portions of the seat-back strength-member being interconnected via a retaining device which normally prevents involuntary pivoting of the upper portion, said retaining device having a mechanical resistance which is chosen so that the retaining device gives way when the upper portion of the seat-back is in a position other than the second angular position and said thrust member is subjected to a rearwardly-directed force in excess of a predetermined value, in the event of an impact from behind, and the headrest is mounted on the upper portion of the seat-back so as to be subjected to the same movement as said upper portion in the event of an impact from behind;wherein said seat further includes energy absorption means for braking the upper portion of the seat-back strength-member throughout angular movement thereof, while said upper portion is moving into the second angular position, in the event of an impact from behind; andwherein the retaining device is a non-reversible control mechanism driven by a control member, said control mechanism being adapted to move the upper portion of the seat-back strength-member between the first and second angular positions as a function of actuation of the control mechanism, and to lock said upper portion of the seat-back strength-member when the control mechanism is unactuated.