3929374 is referenced by 127 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.

Title
Vehicle seat with headrest movement responsive to seat back tilting
Application Number
05/520,311
Publication Number
3929374
Application Date
November 4, 1974
Publication Date
December 30, 1975
Inventor
Weik Kirby B
Hogan Gerard T
Agent
Page II William H
Liggett Philip T
Hoatson Jr James R
Assignee
Universal Oil Products Company
IPC
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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