Air bag device

• US 20060001244A1
• Filed: 06/24/2005
• Published: 01/05/2006
• Est. Priority Date: 06/28/2004
• Status: Active Grant

• Current Assignee: Ashimori Industry Company Limited, Mazda Motor Corporation
• Original Assignee: Ashimori Industry Company Limited, Mazda Motor Corporation
• Inventors: Taguchi, Seigo, Yamaji, Naoki, Ishigame, Katsuyoshi, Sugahara, Tsutomu, Azuma, Hidetaka
• Granted Patent: US 7,431,329 B2
• Time in Patent Office: Days
• US Class Current: 280/729
• CPC Class Codes: B60R 2021/23316 Inner seams, e.g. creating separate compartments or used as tethering means
• CPC Class Codes: B60R 21/23138 specially adapted for side protection B60R21/23184, B60R21/232 take precedence
• CPC Class Codes: B60R 21/2346 Soft diffusers
• CPC Class Codes: B60R 21/239 characterised by their venting means

Abstract

Expansion of an air bag can be smoothly effected even in a small space by controlling the air bag in thickness and introduction of the gas for expansion, and the protection of an occupant can be rapidly implemented with a relatively small volume of the gas. An air bag device comprises a first air chamber 12 for protection of the chest or the waist of an occupant, a second air chamber 14 for protection of the head of the occupant, and a lower portion of the diffuser bag 30 interposed therebetween for portioning out gas from an inflator 20, wherein the second air chamber 14 has a first tether 50 forming a gas passage 14a for guiding gas jetted from gas outlets of the lower portion of the diffuser bag 30 into the second air chamber 14 so as to go around the tether of a head protection region of an air bag 1, from the back side thereof toward the front side thereof, and has a second tether 52 for forming a gap provided at the lower end of the first tether 50 in the vicinity of the gas outlets, for letting a portion of the gas escape into a front part of the second air chamber 14.

Claims

1. An air bag device comprising a first air chamber for protection of the chest or the waist of an occupant, a second air chamber for protection of the head of the occupant, and a diffuser interposed therebetween, having a first communicating hole, and a second communicating hole, for portioning out gas from an inflator to the second air chamber, and the first air chamber, respectively, wherein the second air chamber has a first tether for guiding gas jetted from gas outlets of the diffuser into the second air chamber so as to go around the tether of a head protection region of an air bag from the back side thereof toward the front side thereof, and has a gap provided at the lower end of the first tether in the vicinity of the gas outlets, for letting a portion of the gas escape into a front part of the second air chamber.

2. An air bag device according to claim 1, wherein the first tether is formed by sewing together base clothes forming the second air chamber, on the top face side, and rear face side thereof, respectively, so as to be oriented upward in the second air chamber from the vicinity of the gas outlets of the diffuser.

3. An air bag device according to claim 1, wherein the gap for letting the portion of the gas escape into the front part of the second air chamber is formed by the first tether and a second tether formed by sewing together the base clothes forming the second air chamber, on the top face side, and rear face side thereof, respectively, at a position below the first tether with a predetermined interval provided therebetween.

4. An air bag device according to claim 1, wherein a tether is provided in a shoulder protection region, inside the second air chamber, such that the shoulder protection region of the air bag, at the time of expansion, is controlled to be smaller in thickness than the head protection region.

5. An air bag device according to claim 1, wherein when pressure inside the diffuser becomes lower than pressure inside the second air chamber, the first communicating hole for portioning out the gas from the inflator into the second air chamber are closed owing to a difference in pressure therebetween.

6. An air bag device comprising a first air chamber for protection of the chest or the waist of an occupant, a second air chamber for protection of the head of the occupant, and a diffuser interposed therebetween, having a first communicating hole, and a second communicating hole, for portioning out gas from an inflator to the second air chamber, and the first air chamber, respectively, wherein the second air chamber has a first tether for guiding gas jetted from gas outlets of the diffuser into the second air chamber so as to go around the tether of a head protection region of an air bag, from the back side thereof toward the front side thereof, and has a shoulder protection region continuous from the head protection region, joined to the first air chamber, as well as second tethers for controlling the thickness of the shoulder protection region.

7. An air bag device according to claim 6, wherein at least one of the second tethers is disposed at a position adjacent to the gas outlets of the diffuser of the second air chamber, away from the first tether with a gap provided therebetween, enabling the gas to flow into the shoulder protection region through the gap.

8. An air bag device according to claim 7, wherein the at least one of the second tethers is formed by sewing together base clothes, on the top face side, and rear face side of the air bag, respectively, into the shape of a circle.

9. An air bag device according to claim 6, wherein when pressure inside the diffuser becomes lower than pressure inside the second air chamber, the first communicating hole for portioning out the gas from the inflator into the second air chamber is closed owing to a difference in pressure therebetween.

10. An air bag device comprising a first air chamber for protection of the chest or the waist of an occupant, a second air chamber for protection of the head of the occupant, and a diffuser in a bag-like shape, interposed therebetween, having a first communicating hole, and a second communicating hole, for portioning out gas from an inflator to the second air chamber, and the first air chamber, respectively, wherein the second air chamber has a first tether for guiding gas jetted from gas outlets of the diffuser through the first communicating hole into the second air chamber so as to go around the tether of a head protection region of an air bag, from the back side thereof toward the front side thereof while the second communicating hole is formed so as to be smaller in opening area than the first communicating hole, and vent holes are formed in the first air chamber.

11. An air bag device according to claim 10, wherein the second air chamber is provided in a part of the air bag, above the diffuser, and the first air chamber is provided in a part of the air bag, in front of the diffuser.

12. An air bag device according to claim 10, wherein the vent holes of the first air chamber are provided in the vicinity of an edge of the chamber.