Air bag system for a motor vehicle

• US 5,842,718 A
• Filed: 07/14/1997
• Issued: 12/01/1998
• Est. Priority Date: 03/22/1995
• Status: Expired due to Fees

• Current Assignee: Daewoo Electronics (Government of South Korea)
• Original Assignee: Daewoo Electronics (Government of South Korea)
• Inventors: Byon, Sung-Kwang
• Primary Examiner(s): Dickson, Paul N.
• Application Number:
  US08/892,105
• Time in Patent Office: 505 Days
• Field of Search: 280/728.1, 280/735, 280/736, 280/741
• US Class Current: 280/736
• CPC Class Codes: B60R 21/01508 detecting forces or pressure in bags or modules
• CPC Class Codes: B60R 21/30 with means to draw ambient air into the flow line and mix such air with the inflation fluid

Abstract

An improved air bag system requires low manufacturing cost and facilitates an installation thereof. A flexible hose is installed between an air bag and an inflator for preliminarily charging air into the air bag, an air pipe is provided for connecting the flexible hose to an inlet manifold of a motor vehicle, a pressure sensor is installed within the flexible hose, and a cut off valve is within the air pipe. A compressor and an air reservoir are provided between flexible hose and the inlet manifold for supplying the air to the air bag through flexible hose and the air pipe. The inflator has a single filter in place of a cooling passage. A collision sensor, an electronic control unit and the inflator constitute a single module except the air bag to easily mount the air bag system to the motor vehicle. Thus, the quantities of a pyrotechnic material and a gas generating material required for inflating the air bag are reduced and the air bag of various sizes is employed while affording a cooling effect to an inflation gas of high temperature and high pressure.

Claims

1. An air bag system for a motor vehicle, said air bag system comprising:

an inflatable air bag;

a collision sensor for sensing a collision of the motor vehicle to generate a collision sensing signal;

an electronic control unit for receiving the collision sensing signal from said collision sensor to control an operation of said inflatable air bag, and for generating an air bag expansion triggering signal when it is judged that the collision is dangerous by receiving the collision sensing signal;

an inflator for injecting an inflation gas into said inflatable air bag in accordance with the air bag expansion triggering signal from said electronic control unit to expand said inflatable air bag;

a first conduit for preliminarily charging air into said inflatable air bag, said first conduit being connected between said inflatable air bag and said inflator;

a second conduit for introducing the air into said first conduit, said second conduit being connected to said first conduit;

an air supplying means for supplying air to said first conduit through said second conduit, said air supplying means being provided between said second conduit and an inlet manifold of the motor vehicle, the air being supplied from the inlet manifold; and

a first valve provided in said second conduit for adjusting an amount of the air admitted into said inflatable air bag and said first conduit in accordance with a control signal from said electronic control unit.

2. An air bag system for a motor vehicle as claimed in claim 1, wherein said air bag system further comprises a pressure sensor installed within said first conduit for sensing an air pressure within said first conduit to generate a pressure sensing signal, and said electronic control unit consistently maintains the quantity of the air preliminarily charging into said inflatable air bag and said first conduit by controlling said first valve in accordance with the pressure sensing signal from said pressure sensor.

3. An air bag system for a motor vehicle as claimed in claim 1, wherein said inflatable air bag is preliminarily charged with the air under an atmospheric pressure in an amount of about 1/2 to about 2/3 of a capacity of said air bag.

4. An air bag system for a motor vehicle as claimed in claim 1, wherein said first conduit is a flexible hose.

5. An air bag system for a motor vehicle as claimed in claim 1, wherein said second conduit is an air pipe.

6. An air bag system for a motor vehicle as claimed in claim 1, wherein said valve is a cut off valve.

7. An air bag system for a motor vehicle as claimed in claim 1, wherein said collision sensor, said electronic control unit and said inflator are formed as a single module.

8. An air bag system for a motor vehicle as claimed in claim 1, further comprising a second valve for discharging the air in the inflatable air bag when an engine of the motor vehicle is stopped.

9. An air bag system for a motor vehicle as claimed in claim 1, wherein said air supplying means includes a compressor for compressing the air supplied from the inlet manifold of the motor vehicle and an air reservoir for reserving the compressed air which is to be supplied to said inflatable air bag through said first and second conduits.

10. An air bag system for a motor vehicle as claimed in claim 1, wherein said inflator comprises:

a cylindrical container including a front, rear and side wall formed as one piece;

a burstable diaphragm for partitioning an internal space of said cylindrical container into a first chamber and a second chamber;

a cylindrical filter mounted to said front wall;

a gas generating material retained in said first chamber for inflating said air bag;

a pyrotechnic material retained in said second chamber for burning said gas generating material; and

pyrotechnic means mounted to said rear wall for igniting said pyrotechnic material.

11. An air bag system for a motor vehicle as claimed in claim 10, wherein said cylindrical filter is mounted to said front wall in concentric arrangement with said side wall.

12. An air bag system for a motor vehicle as claimed in claim 10, wherein said container is comprised of a steel or a stainless steel.

13. An air bag system for a motor vehicle as claimed in claim 10, wherein said diaphragm is a thin metal sealing diaphragm.

14. An air bag system for a motor vehicle as claimed in claim 10, wherein said cylindrical filter is comprised of a metal or a ceramic.

15. An air bag system for a motor vehicle, said air bag system comprising:

an inflatable air bag;

a collision sensor for sensing a collision of the motor vehicle to generate a collision sensing signal;

an electronic control unit for receiving the collision sensing signal from said collision sensor to control an operation of said inflatable air bag, and for generating an air bag expansion triggering signal when it is judged that the collision is dangerous by receiving the collision sensing signal;

an inflator for injecting an inflation gas into said inflatable air bag in accordance with the air bag expansion triggering signal from said electronic control unit to expand said inflatable air bag, said inflator including a cylindrical container having a front, rear and side wall formed as one piece, a burstable thin metal sealing diaphragm for partitioning an internal space of said cylindrical container into a first chamber and a second chamber, a cylindrical filter mounted to the front wall, a gas generating material retained in said first chamber for inflating said air bag, a pyrotechnic material retained in said second chamber for burning the gas generating material and a pyrotechnic means mounted to the rear wall for igniting the pyrotechnic material;

a flexible hose for preliminarily charging air into said inflatable air bag, said flexible hose being connected between said inflatable air bag and said inflator;

an air pipe for introducing the air into said flexible hose, said air pipe being connected to said flexible hose;

an air supplying means for supplying air to said flexible hose through said air pipe, said air supplying means being provided between said air pipe and an inlet manifold of the motor vehicle, the air being supplied from the inlet manifold;

a cut off valve provided to said air pipe for adjusting an amount of the air admitted into said inflatable air bag and said flexible hose in accordance with a control signal from said electronic control unit; and

a pressure sensor installed within said flexible hose for sensing an air pressure within said flexible hose to generate a pressure sensing signal,

wherein said inflatable air bag is preliminarily charged with the air under an atmospheric pressure in an amount of about 1/2 to about 2/3 of a capacity of said air bag, said electronic control unit consistently maintains the quantity of the air preliminarily charging into said inflatable air bag and said flexible hose by controlling said cut off valve in accordance with the pressure sensing signal from said pressure sensor, and said collision sensor, said electronic control unit and said inflator are formed as a single module.

16. An air bag system for a motor vehicle as claimed in claim 15, said container is comprised of a steel or a stainless steel.

17. An air bag system for a motor vehicle as claimed in claim 15, wherein said cylindrical filter is comprised of a metal or a ceramic.

18. An air bag system for a motor vehicle, said air bag system comprising:

an inflatable air bag;

a collision sensor for sensing the collision of the motor vehicle to generate a collision sensing signal;

an electronic control unit for receiving the collision sensing signal from said collision sensor to control an operation of said inflatable air bag, and for generating an air bag expansion triggering signal when it is judged that the collision is dangerous by receiving the collision sensing signal;

an inflator for injecting an inflation gas into said inflatable air bag in accordance with an air bag expansion triggering signal from said electronic control unit to expand said inflatable air bag, said inflator including a cylindrical container being comprised of either a steel or a stainless steel, and having a front, rear and side wall formed as one piece, a burstable thin metal sealing diaphragm for partitioning an internal space of said cylindrical container into a first chamber and a second chamber, a cylindrical filter comprised of either a metal or a ceramic, and mounted to the front wall, a gas generating material retained in said first chamber for inflating said air bag, a pyrotechnic material retained in said second chamber for burning the gas generating material and a pyrotechnic means mounted to the rear wall for igniting the pyrotechnic material;

a flexible hose connected between said inflatable air bag and said inflator for preliminarily charging air into said inflatable air bag;

an air pipe connected between an inlet manifold of the motor vehicle and said flexible hose for introducing the air into said flexible hose;

an air supplying means for supplying air to said flexible hose through said air pipe, said air supplying means being provided between said air pipe and the inlet manifold of the motor vehicle, the air being supplied from the inlet manifold;

a cut off valve provided in said air pipe for adjusting an amount of the air admitted into said inflatable air bag and said flexible hose in accordance with a control signal from said electronic control unit; and

a pressure sensor installed within said flexible hose for sensing an air pressure within said flexible hose to generate a pressure sensing signal,

wherein said inflatable air bag is preliminarily charged with the air under an atmospheric pressure of about 1/2 through 2/3 of a capacity of said air bag, said electronic control unit consistently maintains the quantity of the air preliminarily charging into said inflatable air bag and said flexible hose by controlling said cut off valve in accordance with the pressure sensing signal from said pressure senor, and said collision sensor, said electronic control unit and said inflator are formed as a single module.