GAS GENERATOR

• US 20190054891A1
• Filed: 02/09/2017
• Published: 02/21/2019
• Est. Priority Date: 02/10/2016
• Status: Active Grant

• Current Assignee: Nippon Kayaku Company Limited
• Original Assignee: Nippon Kayaku Company Limited
• Inventors: TANAKA, Yusuke, KOYAMA, Hiroaki, KANAJI, Motohiro, HASEGAWA, Shinya
• Granted Patent: US 10,676,061 B2
• Time in Patent Office: Days
• CPC Class Codes: B60R 2021/26029 Ignitors
• CPC Class Codes: B60R 2021/26076 characterised by casing
• CPC Class Codes: B60R 21/264 using instantaneous generation of gas, e.g. pyrotechnic B60R21/268 takes precedence
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder
• CPC Class Codes: F42B 3/103 Mounting initiator heads in initiators; Sealing-plugs
• CPC Class Codes: F42B 3/12 Bridge initiators F42B3/103, F42B3/11, F42B3/195 take precedence; electric ignitors in propellant charges F42C19/12

Abstract

A gas generator includes a cylindrical housing including a top plate portion and a bottom plate portion, an igniter including an ignition portion charged with an ignition agent, and a fixing portion which is formed from a resin molding and fixes the igniter to the bottom plate portion. The fixing portion includes an annular wall portion surrounding an outer circumferential surface of the ignition portion. The annular wall portion has a lower cover portion provided as being continuous in a circumferential direction on a side of the bottom plate portion so as to cover the outer circumferential surface of the ignition portion as being secured to the outer circumferential surface of the ignition portion and an upper enclosing portion provided on a side of the top plate portion at a distance from the outer circumferential surface of the ignition portion.

Claims

1. A gas generator comprising:

a cylindrical housing constituted of a top plate portion and a bottom plate portion closing axial end portions and a circumferential wall portion provided with a gas discharge opening and containing a combustion chamber accommodating a gas generating agent;

an igniter charged with an ignition agent for burning the gas generating agent; and

a fixing portion fixing the igniter to the bottom plate portion,

the bottom plate portion being provided with an opening,

the igniter including an ignition portion defining an ignition chamber accommodating the ignition agent and a terminal pin connected to the ignition portion for igniting the ignition agent and arranged to pass through the opening,

the fixing portion being formed from a resin molding provided to close the opening and to fill a space between the igniter and the bottom plate portion,

the resin molding including an annular wall portion surrounding an outer circumferential surface of the ignition portion, and

the annular wall portion having a lower cover portion provided as being continuous in a circumferential direction on a side of the bottom plate portion so as to cover the outer circumferential surface of the ignition portion as being secured to the outer circumferential surface of the ignition portion and an upper enclosing portion provided on a side of the top plate portion at a distance from the outer circumferential surface of the ignition portion.

2. The gas generator according to claim 1, wherein

the ignition portion has a substantially cylindrical cup body having a closed upper end and an open lower end and a plug closing the lower end of the cup body and supporting the terminal pin,

the cup body includes a contact portion located on the side of the bottom plate portion and being in contact with the plug and a non-contact portion located on the side of the top plate portion and facing the ignition chamber as not being in contact with the plug, and

the lower cover portion covers at least a part of the contact portion and the upper enclosing portion faces at least a part of the non-contact portion.

3. The gas generator according to claim 1, or wherein

the annular wall portion further has an upper auxiliary cover portion provided as being continuous in the circumferential direction on the side of the top plate portion so as to be located in a gap provided between the outer circumferential surface of the ignition portion and the upper enclosing portion and so as to cover the outer circumferential surface of the ignition portion as being secured to the outer circumferential surface of the ignition portion.

4. The gas generator according to claim 1, wherein

a gate mark is provided in a surface of the upper enclosing portion.

11. The gas generator according to claim 1, the gas generator further comprising an externally attached component externally attached to the annular wall portion, wherein

an inner circumferential surface of the externally attached component and an outer circumferential surface of the annular wall portion are brought in press contact with each other.

12. The gas generator according to claim 11, wherein

the externally attached component is a cup-shaped member which accommodates an enhancer agent arranged to face the ignition portion.

5. A gas generator comprising:

a cylindrical housing constituted of a top plate portion and a bottom plate portion closing axial end portions and a circumferential wall portion provided with a gas discharge opening and containing a combustion chamber accommodating a gas generating agent;

an igniter charged with an ignition agent for burning the gas generating agent; and

a fixing portion fixing the igniter to the bottom plate portion,

the bottom plate portion being provided with an opening,

the igniter including an ignition portion defining an ignition chamber accommodating the ignition agent and a terminal pin connected to the ignition portion for igniting the ignition agent and arranged to pass through the opening,

the fixing portion being formed from a resin molding provided to close the opening and to fill a space between the igniter and the bottom plate portion,

the resin molding including an annular wall portion surrounding an outer circumferential surface of the ignition portion, and

the annular wall portion having a lower cover portion provided as being continuous in a circumferential direction on a side of the bottom plate portion so as to cover the outer circumferential surface of the ignition portion as being secured to the outer circumferential surface of the ignition portion and an upper cover portion provided as being intermittent in the circumferential direction on a side of the top plate portion so as to cover the outer circumferential surface of the ignition portion as being secured to the outer circumferential surface of the ignition portion.

6. The gas generator according to claim 5, wherein

the ignition portion has a substantially cylindrical cup body having a closed upper end and an open lower end and a plug closing the lower end of the cup body and supporting the terminal pin,

the cup body includes a contact portion located on the side of the bottom plate portion and being in contact with the plug and a non-contact portion located on the side of the top plate portion and facing the ignition chamber as not being in contact with the plug, and

the lower cover portion covers at least a part of the contact portion and the upper cover portion covers at least a part of the non-contact portion.

7. The gas generator according to claim 5 or 6, wherein

the annular wall portion further has an upper auxiliary cover portion provided as being intermittent in the circumferential direction on the side of the top plate portion so as to be located between the upper cover portion divided in the circumferential direction and so as to cover the outer circumferential surface of the ignition portion as being secured to the outer circumferential surface of the ignition portion, and

the upper auxiliary cover portion is smaller in thickness in a radial direction than the upper cover portion.

8. The gas generator according to claim 5, wherein

a gate mark is provided in a surface of the upper cover portion.

9. The gas generator according to claim 5, the gas generator further comprising an externally attached component externally attached to the annular wall portion, wherein

an inner circumferential surface of the externally attached component and an outer circumferential surface of the annular wall portion are brought in press contact with each other.

10. The gas generator according to claim 9, wherein

the externally attached component is a cup-shaped member which accommodates an enhancer agent arranged to face the ignition portion.