Daicel Corporation

Hitachi Global Storage Technologies Netherlands B.v.

Katsuhiro Imoto

Teppei Hanano

Haruhiko Yamashita

Masayuki Yamazaki

Shinichiro Ukita

Toshio Kakihara

Shuhji Yamada

Akihiko Mouri

A gas generator comprising, a first ignition device, a first inner tube member including therein the first ignition device and a surrounding wall portion provided with one or a plurality of communication holes, the surrounding wall portion including, in a circumferential direction thereof, a combustion product discharge region and a combustion product non-discharge region, and a housing including a peripheral wall portion and defining therein a first combustion chamber, the peripheral wall portion being provided with a first gas discharge port and a second gas discharge port having an opening pressure higher than the first gas discharge port, and a communication hole-associated region associated with the combustion product discharge region and including only the first gas discharge port formed therein and a communication hole non-associated region associated with the combustion product non-discharge region and including the second gas discharge port formed therein.

Gas generator

A gas generator includes: an ignition device chamber arranged at one end opening of a housing; a diffuser portion provided with a gas discharge port and arranged at another end opening; a pressurized gas chamber arranged between the ignition device chamber and the diffuser portion; a first rupturable plate closing the one end opening between the ignition device chamber and the chamber; a second rupturable plate closing the other end opening between the chamber and the diffuser portion; an igniter and a molded article of a gas generating agent accommodated in the ignition device chamber; a gas charged in the chamber; and an amount A (J/msec) of energy generated per unit time by the gas generating agent, a cross-sectional area B (cm) of the chamber at a portion proximate to the ignition device chamber, and a density C (g/cm) of the gas satisfy A/B&#xd7;C=320 to 490.

The present invention provides an igniter assembly in which reliability in operation is enhanced. An igniter assembly includes an igniter main body, a resin portion enclosing a periphery of the igniter main body, a metallic collar being arranged on a periphery of the resin portion and integrated with the resin portion, a cup-like shaped igniter housing filled therein with a gas generating agent or a transfer charge. The metallic collar includes a combination of a cylindrical collar and an annular collar, and the cup-like shaped igniter housing abuts against a portion with a reduced diameter on the side of a first end portion of the cylindrical collar, thereby being fixed from the outside.

Igniter assembly and gas generator using the same

The present invention provides a gas generator in which short-passing of combustion gas is prevented. A cylindrical filterincluding a first annular end surfaceabutted against a top plateand a second annular end surfaceabutted against a bottom plateis disposed inside a housing. A corner portionformed by a bottom surfaceand an outer circumferential wallof a support memberis abutted against an abutting portion between the second annular end surfaceand the bottom plateto prevent the short-passing of the combustion gas from this portion.

The present invention provides a gas generator wherein a diffuser portion having a gas discharge port is disposed at one end of a cylindrical housing; an ignition device is disposed at the other end of the cylindrical housing; an axially-movable metallic partition wall having a plurality of through-holes is disposed between the ignition device and the diffuser portion; a space between the partition wall and the ignition device is an ignition device chamber charged with a molded article of a first gas generating agent; a space between the partition wall and the diffuser portion is a combustion chamber charged with a molded article of a second gas generating agent; the partition wall has a circular bottom surface and an annular wall extending, in a single direction, perpendicularly to an outer circumference of the circular bottom surface, and the circular bottom surface is disposed so as to be on the diffuser portion side; the ignition device has an igniter having a disk-shaped ignition portion protruding toward the partition wall and a metallic annular member having an annular wall and disposed around the ignition portion; and the annular wall of the annular member protrudes to the partition wall further than the distal end surface of the ignition portion.

A gas generator includes a cylindrical housing, a diffuser portion, a first combustion chamber defined by a first porous plate member, a second combustion chamber defined by a second porous plate member, and an ignition device having an ignition portion attached to an igniter collar. The first porous plate member comprises first through holes arranged in the vicinity of a peripheral edge portion. An annular space is formed between an outer peripheral surface of the ignition portion and an inner peripheral wall surface of the cylindrical housing. The height (H) of a top surface of the ignition portion from the igniter collar and a smallest length (Lmin) of a first gas generating agent in the first combustion chamber satisfies a relation Lmin&#x3c;H. An axis of the cylindrical housing is coincident with a central line of the ignition portion, the first porous plate member, and the second porous plate member.

In one embodiment, a HDD creates a segment table to associate an address of user data in a flash memory with an LBA in a magnetic disk. The HDD updates the segment table in a DRAM and saves it to the flash memory at a specific timing. The HDD creates journals indicating the update of the segment table and saves it to the flash memory. The latest segment table can be restored using the segment table and the journals in the flash memory.

Growing community of inventors

Tatsuno, Japan

Katsuhiro Imoto