Horn activator for steering wheels with air bags

• US 5,398,962 A
• Filed: 02/14/1994
• Issued: 03/21/1995
• Est. Priority Date: 02/14/1994
• Status: Expired due to Term

• Current Assignee: Key Safety Systems, Inc. (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Force Imaging Technologies, Inc. (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Kropp, Harry C.
• Primary Examiner(s): Tyson, Karin L.
• Assistant Examiner(s): English, Peter C.
• Application Number:
  US08/195,215
• Time in Patent Office: 400 Days
• Field of Search: 280/728 B, 280/731, 280/728 R, 280/728 A, 280/735, 200/61.54, 200/61.55
• US Class Current: 280/731
• CPC Class Codes: B60Q 5/003 mounted on the steering wheel
• CPC Class Codes: B60R 21/21658 with integrated switches, e.g. horn switches
• CPC Class Codes: H01H 13/785 characterised by the material of the contacts, e.g. conductive polymers
• CPC Class Codes: H01H 2201/036 Variable resistance
• CPC Class Codes: H01H 2239/03 Avoiding erroneous switching
• CPC Class Codes: H01H 2300/018 Application transfer; between utility and emergency power supply

Abstract

A steering wheel having a pressure-sensitive horn activator integrated with an airbag assembly. The horn activator is configured for quick activation, while avoiding accidental activation due to changes in ambient temperatures and pressures.

Claims

1. A steering wheel assembly for use in a vehicle having a horn, said assembly comprising a steering wheel, an inflatable air bag located within the perimeter of the steering wheel, and a horn activator overlying the inflatable airbag, said horn activator comprising a force sensor, and circuit means connected to said force sensor for sensing the change in the force applied to said sensor during a predetermined period, for determining whether the change has reached a selected threshold value, and for activating a horn if said change at least equals said selected threshold value.

2. A steering wheel assembly in accordance with claim 1, and wherein said force sensor is a thin flexible sensor comprising a pair of thin backing sheets, each having an electrode thereon disposed in a confronting pattern and pressure sensitive resistive material therebetween, the resistance of said resistive material changing with changes in the force applied against said force sensor.

3. A steering wheel assembly in accordance with claim 1 and wherein said force sensor is disposed in a cover assembly mounted on said steering wheel and overlying said airbag.