Gas generator for air bag and air bag apparatus

• US 20060131853A1
• Filed: 12/22/2005
• Published: 06/22/2006
• Est. Priority Date: 10/04/1999
• Status: Active Grant

• Current Assignee: Nobuyuki Katsuda, Nobuyuki Ohji, Yasunori Iwai, Yoshihiro Nakashima
• Original Assignee: Nobuyuki Katsuda, Nobuyuki Ohji, Yasunori Iwai, Yoshihiro Nakashima
• Inventors: Ohji, Nobuyuki, Iwai, Yasunori, Katsuda, Nobuyuki, Nakashima, Yoshihiro
• Granted Patent: US 7,207,597 B2
• Time in Patent Office: Days
• US Class Current: 280/736
• CPC Class Codes: B60R 2021/2633 with a plurality of inflation levels
• CPC Class Codes: B60R 2021/2648 comprising a plurality of combustion chambers or sub-chambers
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder

Abstract

A gas generator for an air bag in which safety and reliability are improved. Even when a gas generating agent 9a inside a first combustion chamber 5a is burnt, a gas generating agent 9b is prevented from being burnt by function of a metal thin plate 11 closing a communication hole 10 with a second combustion chamber 5b. A cup 1190 having a hole 1191 is covered on an igniter 1112, and the flame thereof advances into a transfer charge 1116 straightly in a narrow width. Accordingly, since the transfer charge 1116 is burnt completely, sufficient flame for burning a gas generating agent 1109 can be generated securely. An igniter and a transfer charge are stored in an ignition means accommodating chamber 2008, and the charge density of a transfer charge 2016a inside a transfer charge accommodating chamber 2015a is in the range of 0.1 to 5 g/cm³. A communication hole 3010 between a first combustion chamber 3005a and a second combustion chamber 3005b is closed by double-layered seal tape 3011 laminated through an adhesive layer. After activation, the seal tapes 3011 are not ruptured due to increase in the internal pressure of the first combustion chamber 3005a, but they are peeled off easily due to increase in the internal pressure of the second combustion chamber 3005b.

Claims

1. A gas generator for an air bag comprising a housing having a gas discharge port, and an ignition means to be actuated by the impact and a gas generating means which is to be ignited and burnt by the ignition means for generating a combustion gas to inflate an air bag, the ignition means and the gas generating means stored in the housing, wherein the respective gas generating means are stored in the housing, a first combustion chamber and a second combustion chamber with a communication hole for allowing communication between the chambers are also provided in the housing, the communication hole between the first combustion chamber and the second combustion chamber is closed by a plurality of metal thin plates layered through an adhesive.

2. A gas generator for an air bag according to claim 1, wherein the metal thin plates are layered in a non-flat state.

3. A gas generator for an air bag according to claim 1, wherein the total thickness of a plurality of metal thin plates layered except for the adhesive is in the range of 10 to 200 μ

m.

4. A gas generator for an air bag according to claim 1, wherein the thickness of each metal thin plate is in the range of 5 to 100 μ

m.

5. A gas generator for an air bag according to any one of claims 1, wherein the thickness of a first adhesive layer provided on a contacting surface between a peripheral edge portion of the communication hole and a first metal thin plate is in the range of 10 to 50 μ

m.

6. A gas generator for an air bag according to any one of claims 1, wherein the thickness of a second adhesive layer provided on a contacting surface between the first metal thin plate and a second metal thin plate is in the range of 10 to 50 μ

m.

7. A gas generator for an air bag according to any one of claims 1, wherein the communication hole is closed by the metal thin plate from the side of the inner wall of the first combustion chamber.