Inflatable bags for airbag passive restraint systems for driver and method for production thereof

• US 5,358,273 A
• Filed: 02/16/1993
• Issued: 10/25/1994
• Est. Priority Date: 03/09/1992
• Status: Expired due to Fees

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: TOYO Tire & Rubber Company Limited
• Inventors: Onishi, Osamu, Ozaki, Toru, Sugiura, Koji, Onoda, Atsushi, Sogi, Hidehito, Fukushima, Shigeyoshi
• Primary Examiner(s): Rice, Kenneth R.
• Assistant Examiner(s): Ellis, Christopher P.
• Application Number:
  US08/017,874
• Time in Patent Office: 616 Days
• Field of Search: 280/743 R, 280/728 R, 280/743 A, 280/729, 280/731
• US Class Current: 280/743.1
• CPC Class Codes: B60R 2021/23324 Inner walls crating separate compartments, e.g. communicating with vents
• CPC Class Codes: B60R 2021/23382 Internal tether means
• CPC Class Codes: B60R 21/203 in steering wheels or steering columns
• CPC Class Codes: B60R 21/233 comprising a plurality of individual compartments; comprising two or more bag-like members, one within the other B60R21/232 takes precedence
• CPC Class Codes: B60R 21/2338 Tethers

Abstract

An inflatable bag for airbag passive restraints for driver which comprises upper and lower circular base cloths of the same size seamed together at their outer peripheries and lateral regulating means for regulating inflation of the bag in lateral and upward directions and causing downward inflation, which means extends to link between an inner periphery of the lower base cloth and the outer peripheries in a shorter length than the radial distance therebetween, thus forming a sag portion on the lower cloth. When the bag is deployed, the lateral regulating means enables the sag portion to bulge sideways out of a steering wheel to protect a driver. The bag may further include upward restricting means for upward inflation. The lateral and the upward regulating means may be located in a whole circumferential area or within a range of 1/2 to 1/4 the circumference of both cloths. A method of producing the bag having lateral or both regulating means is characterized by using a third cloth of the same size having strap-like portion or portions defined by communicating hole or holes. After superposing and sewing of the lower, upper and third cloths, the strap-like portions are each raised and folded into two and sewn at two roots, thus forming the lateral means. Then the folded strap-like portions are cut at one root and the unfolded strap ends are sewn to the upper base cloth to form upward strap members.

Claims

1. An inflatable bag for an airbag passive restraint system of a vehicle, comprising:

a generally circular upper base cloth;

a lower base cloth of generally the same size and shape as the upper base cloth, said upper and lower base cloths being seamed together at respective outer peripheral portions thereof and being adapted to face toward the driver and to be connected to an inflator for releasing gas into the inflatable bag for inflation thereof, said lower base cloth having a central opening through which to communicate with the inflator; and

lateral regulating means for regulating the inflation of the bag in lateral and upward directions and causing downward inflation in a lower area of the bag, said lateral regulating means having a length which is shorter than a radial distance between the outer peripheral portions of both cloths and an inner peripheral portion around the central opening of the lower base cloth, said lateral regulating means extending radially to link the inner peripheral portion of the lower base cloth and the outer peripheral portions of both cloths in a mutually opposing manner to shorten a radial distance between the inner and outer peripheral portions thus forming, in a non-inflated state, a circumferential sag portion which enables downward inflation of the lower base cloth.

2. The inflatable bag as set forth in claim 1, wherein said lateral regulating means includes a plurality of strap members disposed in a circumferentially spaced relation.

3. The inflatable bag as set forth in claim 1, wherein said lateral regulating means includes at least one laterally regulating strap member disposed within the range of 1/2 to 1/4 the circumference of both cloths.

4. An inflatable bag as set forth in claim 1, further comprising upward regulating means for restricting an upward flaring of the bag, said upward regulating means extending upwardly from the inner peripheral portion of the lower base cloth to a central circular portion of the upper base cloth, said upward regulating means including at least one strap member.

5. The inflatable bag as set forth in claim 4, wherein said upward regulating means includes a plurality of strap members disposed in a whole circumferential area of the inner peripheral portion and the central circular portion in a circumferentially spaced relation.

6. The inflatable bag as set forth in claim 3, further comprising an upward regulating means having at least one upwardly regulating strap member disposed in the range of 1/2 to 1/4 the circumference of both cloths in the same circumferential area as the lateral regulating means.

7. The inflatable bag as set forth in claim 1, wherein said lateral regulating means has a length of 30-80% the radial distance between the outer peripheral portions of both cloths and the inner peripheral portion of the lower base cloth.

8. The inflatable bag as set forth in claim 4, wherein said lateral regulating means has a length of 30-80% the radial distance between the outer peripheral portions of both cloths and the inner peripheral portion of the lower base cloth.

11. An inflatable bag as set forth in claim 3, wherein said lateral regulating means includes a plurality of laterally regulating strap members disposed within the range of 1/2 to 1/4 the circumference of both cloths, the strap members being disposed in a circumferentially spaced relation.

12. An inflatable bag as set forth in claim 6, wherein said lateral regulating means and said upward regulating means each include a plurality of laterally regulating strap members and upwardly regulating strap members, respectively, the respective strap members being disposed in a circumferentially spaced relation.

13. An inflatable bag as set forth in claim 1, wherein said vehicle includes a steering wheel and a means central of the steering wheel for deploying said inflatable bag, and wherein said lateral regulating means, upon inflation of said bag results in an orientation of said sag portion radially outside of a radially outer perimeter of said steering wheel so that the inflation of said sag portion will cause said sag portion to be oriented between a vehicle operator and said steering wheel.

9. A method of producing an inflatable bag having an upper base cloth, a lower base cloth of generally the same size and form as the upper base cloth and having a central opening through which to communicate with an inflator, a lateral regulating means for regulating inflation of the bag in lateral and upward directions and causing downward inflation in a lower area thereof, and a third cloth having the same size and form as the upper and lower base cloths and the same central opening as the lower base cloth, the third cloth forming the lateral regulating means and having at least one strap-like portion, the strap-like portion extending radially from the central opening to a radial outer edge of the third cloth and having at least one longitudinal edge of the strap-like portion defined by a communicating hole through the third cloth, which method comprises the steps of:

superposing the third cloth on a reverse side of the lower base cloth and seaming inner peripheral portions of the third and lower cloths around the respective central openings;

superposing the lower base cloth on the upper base cloth so that an obverse side of the lower base cloth may face an obverse side of the upper base cloth and seaming outer peripheral portions of the third, lower base and upper base cloths together;

picking up and raising the at least one strap-like portion of the third cloth to fold the strap-like portion in a circumferential direction into two and seaming the folded strap-like portion at two roots thereof, thus forming the lateral regulating means; and

subsequently, turning the obverse sides of the upper and lower base cloths inside out.

10. A method of producing an inflatable bag having an upper base cloth, a lower base cloth of generally the same size and form as the upper base cloth and having a central opening through which to communicate with an inflator, a lateral regulating means for regulating inflation of the bag in lateral and upward directions and causing downward inflation in a lower area thereof, an upward regulating means for restricting an upward flaring of the bag, and a third cloth having the same size and form as the upper and lower cloths and the same central opening as the lower base cloth, the third cloth forming the lateral regulating means and the upward regulating means and having at least one strap-like portion, the strap-like portion extending radially from the central opening to a radial outer edge of the third cloth and having at least one longitudinal edge of the strap-like portion defined by a communicating hole through the third cloth, which method comprises the steps of:

superposing the third cloth on a reverse side of the lower base cloth and seaming inner peripheral portions of the third and lower cloths around the respective central openings;

superposing the lower base cloth on the upper base cloth so that an obverse side of the lower base cloth may face an obverse side of the upper base cloth and seaming outer peripheral portions of the third, lower base and upper base cloths together;

picking up the at least one strap-like portion of the third cloth to fold the strap-like portion in a circumferential direction into two and seaming the folded strap-like portion at two roots thereof, thus forming the lateral regulating means;

cutting one root of the folded strap-like portion to form an unfolded strap having a free end and seaming the free end to a central circular portion of the upper base cloth at a reverse side of the upper base cloth thereby forming the upward regulating means; and

subsequently, turning the obverse sides of the upper and lower base cloths inside out.