GAS GENERATOR

• US 20130255529A1
• Filed: 03/11/2013
• Published: 10/03/2013
• Est. Priority Date: 04/02/2012
• Status: Active Grant

• Current Assignee: Daicel Corporation
• Original Assignee: Daicel Corporation
• Inventors: KOBAYASHI, Tomoharu, YAMAZAKI, Masayuki, UKITA, Shinichiro
• Granted Patent: US 8,714,091 B2
• Time in Patent Office: Days
• 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
• CPC Class Codes: C06D 5/00 Generation of pressure gas, e.g. for blasting cartridges, starting cartridges, rockets explosive compositions containing an oxidizer, fuels for rocket engines intended for reaction with an oxidant other than air C06B

Abstract

A gas generator includes, a housing integrated at upper and lower circumferential wall plates, an ignition device chamber defined by a cup-shaped container disposed at a bottom plate of the housing, a combustion chamber surrounding the ignition device chamber, an annular filter disposed to face a top plate of the housing, a retainer supporting the annular filter, the retainer including, an annular bottom surface supporting a lower surface of the filter and a cylindrical wall surface press-fitted to a circumferential wall plate of the housing, a circumferential wall of the cup-shaped container in the vicinity of the bottom surface abutting or positioned close to an inner circumferential surface of the annular filter.

During activation, when the housing deforms, the retainer and annular filter move such that the annular filter gas-tightly attaches to the top plate of the diffuser shell. A combustion gas is discharged radially through the annular filter.

Claims

1. A gas generator, comprising:

a housing including,

a diffuser shell having a top plate and an upper circumferential wall plate provided with a gas discharge port, and

a closure shell having a bottom plate and a lower circumferential wall plate,

the housing, forming an outer shell, being obtained by joining and integrating the upper circumferential wall plate and the lower circumferential wall plate;

an ignition device chamber provided within the housing and defined by a cup-shaped container that is disposed in a central part at the bottom plate of the closure shell, and accommodates an ignition device therein;

a combustion chamber defined to surround the ignition device chamber and charged with a gas generating agent;

an annular filter disposed to face the top plate;

a retainer supporting the annular filter and including,

an annular bottom surface supporting at least a portion of a lower surface of the annular filter, and

a cylindrical wall surface extending at least in an axial direction of the housing from an outer circumferential edge of the annular bottom surface, the cylindrical wall surface being fixed by being press-fitted directly or indirectly to a circumferential wall plate formed by the upper circumferential wall plate and the lower circumferential wall plate;

a combustion gas passage formed to pass through from an outer circumferential surface of the filter to the gas discharge port;

the cup-shaped container being disposed such that a bottom surface thereof abutting against or being positioned close to the top plate of the diffuser shell, a circumferential wall thereof in the vicinity of the bottom surface abutting against or being positioned close to an inner circumferential surface of the annular filter,

during activation,

when the housing deforms in the both directions of the top plate of the diffuser shell and the bottom plate of the closure shell, the retainer and the annular filter move such that the annular filter is in gas-tight contact with the top plate of the diffuser shell, a combustion gas passes through the combustion gas passage to be discharged from the gas discharge port after passing radially outward through the annular filter.

2. The gas generator according to claim 1, wherein

the cylindrical wall surface of the retainer extends toward the top plate of the diffuser shell, and a depression and a protrusion are provided in the circumferential direction at a circumferential edge thereof;

when the housing is deformed toward both the top plate of the diffuser shell and the bottom plate of the closure shell and the retainer and the annular filter move toward the top plate of the diffuser shell during the actuation,

the protrusion of the cylindrical wall surface of the retainer is abutted against the top plate of the diffuser shell, and the depression of the cylindrical wall surface of the retainer forms combustion gas passages.

3. The gas generator according to claim 1, wherein

a cylindrical member is disposed within the housing such as to be press-fitted to the lower circumferential wall plate of the closure shell, and such that a gap is formed between the cylindrical member and the top plate of the diffuser shell and also between the cylindrical member and the gas discharge port provided in the upper circumferential wall plate, and

the retainer is press-fitted and fixed to the cylindrical member.

4. The gas generator according to claim 1, wherein

the lower surface of the annular filter is supported by the annular bottom surface of the retainer, and the outer circumferential surface of the annular filter is supported by the cylindrical wall surface of the retainer, and

the retainer has a through-hole in the inner circumferential edge side of the annular bottom surface facing the annular filter.

5. The gas generator according to claim 1, wherein

the inner circumferential surface of the annular filter is arranged to protrude toward the center axis of the housing beyond an inner circumferential edge of the annular bottom surface of the retainer.