Gas generator

Patent metadata

Field	Value
Publication number	US-9527470-B2
Application number	US-201414913197-A
Country	US
Kind code	B2
Filing date	Jul 16, 2014
Priority date	Aug 20, 2013
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

The present invention provides a gas generator including
an ignition device provided at one end of a cylindrical housing and a diffuser portion having a gas discharge port and provided at the other end of the housing, molded articles of a gas generating agent and a molded article of a pressure increasing agent charged into a combustion chamber inside the cylindrical housing, the molded articles of a gas generating agent charged into a charging space remained except for a charging portion for the molded article of a pressure increasing agent inside the combustion chamber such that the molded articles of a gas generating agent are in contact with the ignition device and a total volume of the molded articles of a gas generating agent is less than a volume of the charging space, the molded article of a pressure increasing agent charged in contact with the molded articles of a gas generating agent at a position axially distant from the ignition device, a combustion temperature of the molded articles of a gas generating agent being 1000° C. to 1700° C., and a combustion temperature of the molded article of a pressure increasing agent being higher than that of the molded articles of a gas generating agent, a charged mass of the molded articles of a gas generating agent being larger than a charged mass of the molded article of a pressure increasing agent, and the molded article of a pressure increasing agent being to burn out before burnout of the molded articles of a gas generating agent at the time of actuation.

First claim

The invention claimed is:

1. A gas generator, comprising:
an ignition device provided at one end of a cylindrical housing and a diffuser portion having a gas discharge port and provided at the other end of the housing,
molded articles of a gas generating agent and a molded article of a pressure increasing agent charged into a combustion chamber inside the cylindrical housing,
the combustion chamber being a space inside the cylindrical housing excluding the ignition device and the diffuser portion,
the molded articles of a gas generating agent being charged, in a charging space remained except for a charging portion for the molded article of a pressure increasing agent inside the combustion chamber, such that the molded articles of a gas generating agent is in contact with the ignition device and a total volume of the molded articles of a gas generating agent is less than a volume of the charging space,
the molded article of a pressure increasing agent being charged in contact with the molded articles of a gas generating agent at a position axially distant from the ignition device in the combustion chamber,
a combustion temperature of the molded articles of a gas generating agent being 1000° C. to 1700° C., and a combustion temperature of the molded article of a pressure increasing agent being higher than that of the molded articles of a gas generating agent,
a charged mass of the molded articles of a gas generating agent being larger than a charged mass of the molded article of a pressure increasing agent, and
the molded article of a pressure increasing agent being to burn out before burnout of the molded articles of a gas generating agent at the time of actuation.

2. The gas generator according to claim 1 , wherein
the total volume (V1)of the molded articles of a gas generating agent and the volume (V2) of the charging space of the molded articles of a gas generating agent satisfy the relationship V1/V2=0.50 to 0.90 when the molded articles of a gas generating agent do not have a through hole.

3. The gas generator according to claim 1 , wherein
the molded article of a pressure increasing agent is charged between a position at a distance of 1/3L from the ignition device and the diffuser portion, where L stands for the length of the combustion chamber.

4. The gas generator according to claim 1 , wherein,
inside the combustion chamber,
the molded article of a pressure increasing agent is charged such as to form a disk abutting against the inner circumferential surface of the cylindrical housing, and
the molded articles of a gas generating agent are charged into one or two remaining columnar spaces.

5. The gas generator according to claim 1 , wherein
a filter is disposed between the combustion chamber and the diffusion portion.

6. The gas generator according to claim 1 , wherein
the molded articles of a gas generating agent and the molded article of a pressure increasing agent are different from each other in at least one of shape, size, composition and composition ratio.

7. A gas generator, comprising:
an ignition device provided at one end of a cylindrical housing and a diffuser portion having a gas discharge port and provided at the other end of the housing,
molded articles of a gas generating agent and a molded article of a pressure increasing agent charged into a combustion chamber inside the cylindrical housing,
the combustion chamber being a space inside the cylindrical housing excluding the ignition device and the diffuser portion,
the molded articles of a gas generating agent being charged, in a charging space remained except for a charging portion for the molded article of a pressure increasing agent inside the combustion chamber, such that the molded articles of a gas generating agent is in contact with the ignition device and a total volume of the molded articles of a gas generating agent is less than a volume of the charging space,
the molded article of a pressure increasing agent being charged in the end portion of the combustion chamber opposite the ignition device, and the molded article of a pressure increasing agent and the molded articles of a gas generating agent being separated by a partition wall,
the partition wall being selected from a partition wall formed of a metal that is melted and deformed by heat at the time of actuation, a partition wall that is burned by heat at the time of actuation, a partition wall that is not melted or deformed by heat at the time of actuation but has ports,
a combustion temperature of the molded articles of a gas generating agent being 1000° C. to 1700° C., and a combustion temperature of the molded article of a pressure increasing agent being higher than that of the molded articles of a gas generating agent,
a charged mass of the molded articles of a gas generating agent being larger than a charged mass of the molded article of a pressure increasing agent, and
the molded article of a pressure increasing agent being to burn out before burnout of the molded articles of a gas generating agent at the time of actuation.

8. The gas generator according to claim 7 , wherein
the total volume (V1) of the molded articles of a gas generating agent and the volume (V2) of the charging space of the molded articles of a gas generating agent satisfy the relationship V1/V2=0.50 to 0.90 when the molded articles of a gas generating agent do not have a through hole.

9. The gas generator according to claim 7 , wherein
the molded article of a pressure increasing agent is charged between a position at a distance of 1/3L from the ignition device and the diffuser portion, where L stands for the length of the combustion chamber.

10. The gas generator according to claim 7 , wherein,
inside the combustion chamber,
the molded article of a pressure increasing agent is charged such as to form a disk abutting against the inner circumferential surface of the cylindrical housing, and
the molded articles of a gas generating agent are charged into one or two remaining columnar spaces.

11. The gas generator according to claim 7 , wherein
the molded articles of a gas generating agent and the molded article of a pressure increasing agent are different from each other in at least one of shape, size, composition and composition ratio.

Assignees

• Daicel Corp

Inventors

• Hanano Teppei
• Yamazaki Masayuki
• Matsuda Naoki

Classifications

• B60R2021/26011

  using a filter through which the inflation gas passes · CPC title

• B60R21/264 Primary

  using instantaneous generation of gas, e.g. pyrotechnic (B60R21/268 takes precedence) · CPC title

• F42B3/04

  for producing gas under pressure {(generators of inflation fluid especially adapted for vehicle air bags B60R21/26)} · CPC title

• B60R21/2644 Primary

  using only solid reacting substances, e.g. pellets, powder · CPC title