Gas generator

• US 8,011,303 B2
• Filed: 04/14/2008
• Issued: 09/06/2011
• Est. Priority Date: 04/18/2007
• Status: Active Grant

• Current Assignee: Daicel Chemical Industries Limited
• Original Assignee: Daicel Chemical Industries Limited
• Inventors: Noma, Noriaki, Nikko, Takeo, Nakayasu, Masayuki
• Primary Examiner(s): Carone; Michael
• Assistant Examiner(s): Abdosh; Samir
• Application Number:
  US12/081,311
• Publication Number:
  US 20080257195A1
• Time in Patent Office: 1,240 Days
• Field of Search: 102/530
• US Class Current: 102/530
• CPC Class Codes: B60R 2021/26011 using a filter through which the inflation gas passes
• 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 includes, a housing defining a first combustion chamber and accommodating an enhancer chamber cup member, defining an enhancer chamber, and a combustion chamber cup member provided outside the enhancer chamber cup member and defining a second combustion chamber. The enhancer cup member accommodates a first gas generating agent ignited by a first ignition device, and has an enhancer hole for communicating the enhancer chamber with the first combustion chamber during activation. The combustion chamber cup member accommodates a second gas generating agent ignited by a second ignition device, and has a through-hole for communicating the second combustion chamber with the first combustion chamber during activation. A top plate of the enhancer chamber cup member is positioned higher than a top plate of the combustion chamber cup member, and the enhancer hole is positioned higher than the top plate of the combustion chamber cup member.

Claims

1. A gas generator, comprising:

a housing including a diffuser shell provided with a gas discharge port and a closure shell, a cylindrical filter disposed inside the housing, a first combustion chamber defined inside the cylindrical filter, and a second combustion chamber defined inside the first combustion chamber,

the first combustion chamber having an enhancer chamber and a first gas generating agent stored outside the enhancer chamber,

the enhancer chamber, being defined by an enhancer chamber cup member and accommodating therein a first ignition device for igniting and combusting the first gas generating agent,

the enhancer chamber cup member including a first end, a second end opposite to the first end, and a circumferential surface extending from the first end to the second end, the first end being provided with a first top plate, and the circumferential surface including an enhancer hole communicating the enhancer chamber with the first combustion chamber during activation,

the second combustion chamber being surrounded by a combustion chamber cup member disposed eccentrically to a central axis of the housing, the combustion chamber cup member including a second top plate and a through-hole for communicating the second combustion chamber with the first combustion chamber during activation,

the second combustion chamber accommodating a second ignition device and a second gas generating agent therein, and

the first top plate being positioned higher than the second top plate so that a space accommodating the first gas generating agent is provided above the second top plate, and the enhancer hole being provided such that the enhance hole opposes the space where the first gas generating agent is provided.

2. The gas generator according to claim 1, wherein

the second ignition device comprises an electric igniter, and

the combustion chamber cup member includes a cylindrical member having a first opening portion and a second opening portion opposite to the first opening portion, and provided such that the first opening portion is in contact with a bottom surface of the housing, and the second top plate, provided separately from the cylindrical member, is placed on the second opening portion to cover the second opening portion, and

wherein the second top plate is provided with a protruding portion at the center thereof.

3. The gas generator according to claim 1, wherein

a ratio H2/H1 of a height (H2) of the combustion chamber cup member to a height (H1) of the enhancer chamber cup member is within a range of 0.3 to 0.9, and the height of the enhancer chamber cup member is equal to a height from a bottom surface to a ceiling surface of the housing.

4. The gas generator according to claim 1, wherein

the housing has a round planar shape, the filter has a round planar shape, the enhancer chamber cup member has a round planar shape, and the combustion chamber cup member has a circular arc planar shape, and

the combustion chamber cup member is disposed so that a curved portion thereof is positioned on the inner wall surface side of the filter, and a flat portion thereof is positioned on the side of the enhancer chamber cup member.

5. The gas generator according to claim 1, wherein

the housing has a round planar shape, the filter has a round planar shape, the enhancer chamber cup member has a round planar shape, and the combustion chamber cup member has a planar shape similar to a circular arc comprising a circumference and a concave curve, and

the combustion chamber cup member is disposed so that a curved portion thereof is positioned on the inner wall surface side of the filter, and a concave curved portion thereof is positioned on the side of the enhancer chamber cup member.

7. The gas generator according to claim 2, wherein

a ratio H2/H1 of a height (H2) of the combustion chamber cup member to a height (H1) of the enhancer chamber cup member is within a range of 0.3 to 0.9, and the height of the enhancer chamber cup member is equal to a height from a bottom surface to a ceiling surface of the housing.

8. The gas generator according to claim 2, wherein

the housing has a round planar shape, the filter has a round planar shape, the enhancer chamber cup member has a round planar shape, and the combustion chamber cup member has a circular arc planar shape, and

the combustion chamber cup member is disposed so that a curved portion thereof is positioned on the inner wall surface side of the filter, and a flat portion thereof is positioned on the side of the enhancer chamber cup member.

9. The gas generator according to claim 2, wherein

the housing has a round planar shape, the filter has a round planar shape, the enhancer chamber cup member has a round planar shape, and the combustion chamber cup member has a planar shape similar to a circular arc comprising a circumference and a concave curve, and

the combustion chamber cup member is disposed so that a curved portion thereof is positioned on the inner wall surface side of the filter, and a concave curved portion thereof is positioned on the side of the enhancer chamber cup member.

6. A gas generator, comprising:

a housing including a diffuser shell provided with a gas discharge port and a closure shell, the housing defining therein a first combustion chamber accommodating a first gas generating agent therein;

an enhancer chamber cup member provided within the first combustion chamber and defining an enhancer chamber accommodating therein a first ignition device for igniting and combusting the first gas generating agent, the enhancer chamber cup member including a first end, a second end opposite to the first end, and a circumferential surface extending from the first end to the second end, the first end being provided with a first top plate, and the circumferential surface being provided with an enhancer hole communicating the enhancer chamber with the first combustion chamber during activation; and

a combustion chamber cup member provided eccentrically to a central axis of the housing within the first combustion chamber, the combustion chamber cup member defining a second combustion chamber including therein a second ignition device and a second gas generating agent, and having a second top plate and a through-hole for communicating the second combustion chamber with the first combustion chamber during activation, the combustion chamber cup member being provided such that the enhancer hole is provided in the circumferential surface of the enhancer cup member at a height between the first top plate and the second top plate,

the first top plate being positioned higher than the second top plate so that a space accommodating the first gas generating agent is provided above the second top plate, and the enhancer hole being provided such that the enhancer hole opposes the space where the first gas generating agent is provided.

10. A gas generator, comprising:

a housing;

a first combustion chamber defined inside the housing;

an enhancer chamber cup member accommodated inside the first combustion chamber and defining, therein, an enhancer chamber, the enhancer chamber cup member having a first end, a second end opposite to the first end, a circumferential surface extending from the first end to the second end, a first top plate provided at the first end, and an enhancer hole provided in the circumferential surface for communicating the enhancer chamber with the first combustion chamber during activation; and

a combustion chamber cup member accommodated inside the first combustion chamber and outside the enhancer chamber cup member and defining therein a second combustion chamber, the combustion chamber cup member having a second top plate at an upper end thereof and a through-hole for communicating the second combustion chamber with the first combustion chamber during activation,

wherein the enhancer chamber cup member accommodates a first ignition device and a first gas generating agent ignited by the first ignition device,

the combustion chamber cup member accommodates a second ignition device and a second gas generating agent ignited by the second ignition device,

the enhancer hole is provided in the circumferential surface of the enhancer chamber cup member at a height between the first top plate and the second top plate, and

the first top plate is positioned higher than the second top plate so that a space accommodating the first gas generating agent is provided above the second top plate, and the enhancer hole is provided such that the enhancer hole opposes the space where the first gas generating agent is provided.

11. The gas generator according to claim 10, wherein the first top plate is positioned higher than the second top plate.