Steering wheel

• US 5,002,306 A
• Filed: 02/14/1989
• Issued: 03/26/1991
• Est. Priority Date: 04/21/1988
• Status: Expired due to Fees

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Ohno, Satoshi, Hiramitsu, Tetsushi
• Primary Examiner(s): Marmor, Charles A.
• Assistant Examiner(s): GRAYSAY, TAMARA L
• Application Number:
  US07/309,856
• Time in Patent Office: 770 Days
• Field of Search: 280/728, 280/731, 280/743, 280/750, 280/748, 200/61.57, 200/61.56, 200/61.55, 200/61.54
• 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

Abstract

An air bag device is provided on upper side of a boss portion. The air bag device comprises an air bag, an inflater supplying gas to the air bag, a backup plate holding the air bag and the inflater, and a pad in box shape for covering the air bag. A thin breaking portion is formed on an upper wall of the pad so as to break the upper wall in state of connecting the upper wall to the side wall when the air bag is expanded, and a plurality of membrane switches comprising a pair of electrodes in thin film shape are arranged at portions of the upper wall of the pad except for the breaking portion. A connector connected to a prescribed electric circuit at lower side of the boss portion and the membrane switches are electrically connected by lead wires arranged along a pad side wall portion in state of connecting the pad upper wall when the pad upper wall is broken.

Claims

1. A steering wheel which is provided with a ring portion, a boss portion arranged at the center of the ring portion, a spoke portion connecting between the ring portion and the boss portion, and an air bag device comprising:

(a) an air bag capable of being expanded at a prescribed time;

(b) an inflater supplying gas to expand said air bag;

(c) a backup plate arranged on an upper side of said boss portion for holding said air bag and said inflater;

(d) a pad formed in box shape with an upper wall and a side wall extending downward from a periphery of the upper wall, and covering an upper side and lateral side of said air bag and connecting the side wall to said backup plate and having a breakopen area for releasing said air bag and defined by a thinned breaking portion on the upper wall for breaking the upper wall open while leaving a part of the upper wall outside said area connected to the side wall when said air bag is expanded;

(e) a plurality of membrane switches arranged at portions of the upper wall of said pad remote from said thinned breaking portion so as not to cross said thinned breaking portion and comprising a pair of electrodes in thin film shape;

(f) a connector arranged at a lower side of said boss portion and connected to a prescribed electric circuit; and

(g) lead wires connecting said membrane switches to said connector electrically, and arranged along the pad side wall adjacent said part of the upper wall of said pad, said lead wires being remote from said thinned breaking portion so as not to cross said thinned breaking portion.

2. A steering wheel as set forth in claim 1, wherein at least one among the plurality of membrane switches function as a horn switch.

3. A steering wheel as set forth in claim 1 wherein said breaking portion is in the shape of an H and the upper wall above and below the H includes the said upper wall part which remains connected to the side wall when the air bag is expanded.

4. A steering wheel which is provided with a ring portion, a boss portion arranged at the center of the ring portion, a spoke portion connecting between the ring portion and the boss portion, and an air bag device installed on an upper side of the boss portion, said air bag device comprising:

an air bag capable of being expanded at a prescribed time;

an inflater supplying gas to expand said air bag;

a backup plate arranged on an upper side of said boss portion for holding said air bag and said inflater;

a pad formed in box shape with an upper wall and a side wall extending downward from a periphery of the upper wall, and covering an upper side and lateral side of said air bag and connecting the side wall to said backup plate and having a breakopen area for releasing said air bag and defined by a thinned breaking portion on the upper wall for breaking the upper wall open while leaving a part of the upper wall outside said area connected to the side wall when said air bag is expanded;

a plurality of membrane switches arranged at portions of the upper wall of said pad remote from said thinned breaking portion so as not to cross said thinned breaking portions and comprising a pair of electrodes in thin film shape; and

lead wires operatively connecting said plurality of membrane switches to a prescribed electric circuit, said lead wires being arranged remote from said thinned breaking portion so as not to cross said thinned breaking portion.

5. A steering wheel as set forth in claim 4 wherein said breaking portion is in the shape of an H and the upper wall above and below the H includes the said upper wall part which remains connected to the side wall when the air bag is expanded.