Gas generator for air bag

• US 7,487,995 B2
• Filed: 03/09/2006
• Issued: 02/10/2009
• Est. Priority Date: 03/10/2005
• Status: Active Grant

• Current Assignee: Daicel Chemical Industries Limited
• Original Assignee: Daicel Chemical Industries Limited
• Inventors: Matsuda, Naoki, Yabuta, Mikio
• Primary Examiner(s): Nguyen; John Q.
• Assistant Examiner(s): Coker; Robert A.
• Application Number:
  US11/370,867
• Publication Number:
  US 20060214403A1
• Time in Patent Office: 1,069 Days
• Field of Search: 280/736, 280/737, 280/741, 280/742, 102/530, 102/531
• US Class Current: 280/736
• CPC Class Codes: B60R 2021/26094 characterised by fluid flow controlling valves
• CPC Class Codes: B60R 2021/2648 comprising a plurality of combustion chambers or sub-chambers
• CPC Class Codes: B60R 21/261 with means other than bag structure to diffuse or guide inflation fluid
• CPC Class Codes: B60R 21/264 using instantaneous generation of gas, e.g. pyrotechnic B60R21/268 takes precedence

Abstract

A gas generator for an air bag includes a housing having a gas discharge port, a first combustion chamber and a second combustion chamber, each of the combustion chambers being provided with a gas generating agent and an ignition device, being in the housing, the second combustion chamber being separated from the first combustion chamber by a cup member disposed within the housing, the second gas generating agent and the second ignition device being disposed within the cup member, the cup member being moved upon activation of the second ignition device, thereby forming a discharge passage for a gas generated in the second combustion chamber.

Claims

1. A gas generator for an air bag, comprising:

a housing having a gas discharge port,

a first combustion chamber provided with a first gas generating agent and a first iginition device inside the housing; and

a second combustion chamber provided with a second gas generating agent and a second ignition device inside the housing,

the second combustion chamber being separated from the first combustion chamber by a cup member disposed within the housing,

the second gas generating agent and the second ignition device being disposed within the cup member, and

the cup member being moved upon activation of the second ignition device, thereby forming a discharge passage for discharging a gas generated in the second combustion chamber,

wherein the cup member has a closed through-hole in a lower end portion thereof,

when the cup member is moved upon the activation of the second ignition device, the through-hole opens, thereby forming the discharge passage for discharging the gas generated in the second combustion chamber, and

the second ignition device comprises a combination of a second igniter and a second igniter collar, and, by fitting an opening portion of the cup member onto the second igniter collar, the cup member is fixed into position such that the through-hole in the cup member is closed by the second igniter collar.

2. The gas generator for an air bag according to claim 1, wherein a peripheral edge of an opening portion of the cup member is in contact with a bottom face of the housing and a gap exists between a ceiling surface of the cup member and a ceiling surface of the housing, and when the second ignition device is activated, the cup member rises such that the ceiling surface of the cup member impinges on the ceiling surface of the housing, thereby forming the discharge passage for discharging the gas generated in the second combustion chamber.

3. The gas generator for an air bag according to claim 1, wherein the second combustion chamber is located within the first combustion chamber, a first ignition device, including a first igniter and a first igniter collar, is disposed within the first combustion chamber, and a part of a peripheral surface of the cup member is sandwiched between the first igniter collar and the second igniter collar.

4. A gas generator for an air bag, comprising:

a housing having a gas discharge port,

a first combustion chamber disposed inside the housing and provided with a first gas generating agent and a first ignition device;

a second combustion chamber disposed inside the housing and provided with a second gas generating agent and a second ignition device;

a cup member disposed in the housing, the cup member separating the second combustion chamber from the first combustion chamber, the second gas generating agent and the second ignition device being disposed within the cup member, the cup member having a through-hole in a lower end portion thereof and being moved upon activation of the second ignition device,

wherein, the second ignition device comprises a combination of an igniter and an igniter collar, and, by press-fitting an opening portion of the cup member onto the igniter collar, the cup member is fixed into position such that the through-hole in the cup member is closed, and

when the cup member is moved upon activation of the second ignition device, the through-hole opens, thereby exposing the through-hole for discharging the gas generated in the second combustion chamber.