(19) United States
(12) Patent Application Publication (io) Pub. No.: US 2002/0043788 Al
GALLAGHER et al. (43) Pub. Date: Apr. 18,2002
(54) METHOD OF FORMING A MOTOR
VEHICLE INSTRUMENT PANEL WITH A
FLEXIBLY TETHERED AIR BAG
(76) Inventors: MICHAEL J. GALLAGHER,
HAMPTON, NH (US); JOHN D.
GRAY, UNION, NH (US); STEPHEN
D. FARRINGTON, KINGSTON, NH
Steven J. Grossman
HAYES, SOLOWAY, HENNESSEY,
GROSSMAN & HAGE, P.C.
175 Canal Street
Manchester, NH 03101 (US)
( * ) Notice: This is a publication of a continued prosecution application (CPA) filed under 37 CFR 1.53(d).
(21) Appl. No.: 09/127,681
(22) Filed: Jul. 31, 1998
Related U.S. Application Data
(63) Continuation-in-part of application No. 08/426,104, filed on Apr. 21, 1995, now patented.
(51) Int. CI.7 B60R 21/16
(52) U.S. CI 280/728.3; 280/732
A method of forming a motor vehicle instrument panel with a flexibly tethered air bag deployment door comprises the steps of molding an instrument panel with a first plastics material to a desired shape and with an integral air bag deployment door whose opening is defined by a tear seam formed by a groove molded in one side of the panel and with an integral mounting/hinge flange that extends from an inside surface of the door, and forming a bonded layer of second plastics material on one side of the flange and the inside surface of a potentially frangible portion of the door. The second plastics material has the physical characteristic of remaining ductile to a substantial degree at low temperatures substantial below the temperature at which the first plastics material becomes brittle and as a result the bonded layer forms a tether that connects the frangible door portion to the mounting/hinge flange in a flexible manner when this door portion breaks away from the flange because of embrittlement of the first plastics material at the low temperatures on tearing of the tear seam and opening movement of the door by an inflating air bag pressing against the inside surface of the frangible door portion.