Airbag gas generator and an airbag apparatus
First Claim
1. An airbag gas generator, comprising:
- a housing; and
a combustion chamber provided within said housing for burning a gas generating agent therein, said combustion chamber having a first volume before activation of said gas generator, said first volume being increased to a second volume, larger than the first volume, by an initial increase in an inner pressure of the combustion chamber at an initial stage of the activation due to a combustion gas generated by a combustion of said gas generating agent, wherein combustion of the gas generating agent is momentarily suppressed in the initial stage by a decrease in the inner pressure due to the increase in the first volume.
1 Assignment
0 Petitions
Accused Products
Abstract
An airbag gas generator with a simple construction, which operates to apply as small an impact as possible to the passenger during the initial stage of its operation and thereafter rapidly increase the gas pressure to reliably protect the passenger.
The airbag gas generator which includes in the housing with gas discharge ports a single ignition means activated by impacts, a gas generating agent ignited and burned by the ignition means to produce a combustion gas, and a filter means to cool the combustion gas and/or arrest combustion residue. The operation performance of the gas generator is adjusted such that the tank pressure measured at 0.25×T milliseconds will be 0.25×P (kPa) or less where a desired tank maximum pressure in the tank combustion test is P (kPa) and a period of time from the start of rising of the tank pressure to the time when the maximum pressure P (kPa) is reached is T milliseconds.
116 Citations
22 Claims
-
1. An airbag gas generator, comprising:
-
a housing; and
a combustion chamber provided within said housing for burning a gas generating agent therein, said combustion chamber having a first volume before activation of said gas generator, said first volume being increased to a second volume, larger than the first volume, by an initial increase in an inner pressure of the combustion chamber at an initial stage of the activation due to a combustion gas generated by a combustion of said gas generating agent, wherein combustion of the gas generating agent is momentarily suppressed in the initial stage by a decrease in the inner pressure due to the increase in the first volume. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. An airbag apparatus, comprising:
-
an airbag gas generator including, a housing, and a combustion chamber provided within said housing and burning a gas generating agent therein, said combustion chamber including a space having a first volume before activation of said gas generator, said first volume being expanded to a second volume, larger than the first volume, by an inner pressure of a combustion gas generated by a combustion of at least a portion of said gas generating agent to control a combustion of a rest of said gas generating agent;
an impact sensor that detects impacts and activates said gas generator;
an airbag inflated by receiving a gas generated by the gas generator; and
a module case that accommodates the airbag.
-
-
11. An air bag gas generator, comprising:
-
a housing having gas discharge ports;
ignition means provided within said housing for generating a combustion product upon activation thereof, said ignition means including a transfer charge having at least one of nitrogunidine-based and ammonium nitrate-based gas generating agent for generating at least one of combustion gas and heat; and
seal means for closing the gas discharge ports to prevent fluid communication between inside and outside of said housing before activation of said gas generator.
-
-
12. A method of decreasing an amount of gas generated in an initial stage of activation of an air bag gas generator, comprising:
-
providing a housing having gas discharge ports;
providing, within the housing, a combustion chamber having a first volume before activation of the gas generator;
providing gas generating material inside the combustion chamber;
combusting at least a portion of the gas generating material to increase an inner pressure within the combustion chamber; and
increasing, in the initial stage, a volume of the combustion chamber from the first volume to a second volume, larger than the first volume, by the increase in the inner pressure; and
momentarily suppressing combustion of the gas generating material in the initial stage by the decrease in the inner pressure due to the increase in the volume of the combustion chamber. - View Dependent Claims (13)
deforming the housing.
-
-
14. An airbag gas generator, comprising:
-
a housing having a gas discharge port formed in a circumferential wall thereof, ignition means provided within said housing for generating a combustion product upon activation thereof;
a combustion chamber provided within said housing for accommodating therein a gas generating agent;
an ignition means accommodating chamber provided within said housing for accommodating said ignition means therein and including a port for discharging the combustion product therefrom, the port being formed in a circumferential portion of said ignition means accommodating chamber such that an axis of the gas discharge port and an axis of the port are substantially on the same plane and perpendicular to a center axis of said housing;
a single coolant provided within said housing such that said single coolant and the circumferential wall defines a space therebetween and the gas discharge port directly opposes an outer circumference of said single cylindrical coolant; and
seal means for closing the gas discharge port to prevent a fluid communication between an inside and outside of said housing before activation of said gas generator. - View Dependent Claims (15, 16, 17)
-
-
18. An airbag gas generator, comprising:
-
a housing, a combustion chamber provided within said housing for burning a gas generating material therein, said combustion chamber having a first volume before activation of the gas generator, the first volume being expandable to a second volume that is larger than the first volume by pressure generated by combustion of at least a portion of the gas generating material at a predetermined time after activation of the gas generator to control combustion of a remaining portion of the gas generating material and to temporarily decrease inflation gas generated for a period of time after activation of the gas generator. - View Dependent Claims (19, 20, 21)
-
-
22. A method of decreasing gas generation in an initial stage of activation of an air bag gas generator, comprising:
-
providing a housing having at least one gas discharge port;
providing, within the housing, a combustion chamber having a first volume before activation of the gas generator;
providing gas generating material within the combustion chamber;
combusting at least a portion of the gas generating material to increase internal pressure within the housing;
increasing volume of the combustion chamber by the increased internal pressure such that the first volume expands to second volume at a predetermined time after activation of the gas generator, the second volume being larger than the first volume whereby combustion of the gas generating material is temporarily decreased.
-
Specification