3929374 is referenced by 128 patents and cites 11 patents.

A tilting, adjustable passenger seat back is provided with an angularly adjustable upper headrest section which has tilting linkage and a hinge connection to the upper part of the seat back such that when the back is in a generally upright position, the headrest section is back and out of the way of a passenger's head and shoulders; however, when the seat back is moved to a recline position, the headrest section will rotate forward to provide support for the head while the passenger is in the recline position. A modified construction also has additional linkage which provides for a lumbar support that moves along with recline movement to be most effective for upright positioning and out of the way for the recline position.

Vehicle seat with headrest movement responsive to seat back tilting
Application Number
Publication Number
Application Date
November 4, 1974
Publication Date
December 30, 1975
Weik Kirby B
Hogan Gerard T
Page II William H
Liggett Philip T
Hoatson Jr James R
Universal Oil Products Company
A47C 31/00
A47C 01/36
B60N 02/66
B60N 02/64
B60N 02/48
A47C 01/36
A47C 01/31
A47C 07/38
A47C 07/36
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