MULTIPLE IGNITION SYSTEM FOR AIR CUSHION GAS SUPPLY

• US 3,773,352 A
• Filed: 03/30/1972
• Issued: 11/20/1973
• Est. Priority Date: 03/30/1972
• Status: Expired due to Term

• Current Assignee: Donald G. Radke
• Original Assignee: Donald G. Radke
• Inventors: Radke, Donald G.
• Primary Examiner(s): Betts, Kenneth H.
• Assistant Examiner(s): Silverstrim, John P.
• Application Number:
  US05/239,547
• Time in Patent Office: 600 Days
• Field of Search: 280/15AB 180/103 102/7.2R
• US Class Current: 280/731
• CPC Class Codes: B60R 2021/2633 with a plurality of inflation levels
• 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: F42B 3/04 for producing gas under pressure generators of inflation fluid especially adapted for vehicle air bags B60R21/26
• CPC Class Codes: F42B 3/10 Initiators therefor percussion fuzes F42C7/00; percussion caps F42C19/10; electric primers F42C19/12

Abstract

A multiple ignition system for air cushion gas supply of generated gas from pyrotechnic source to compensate for ambient temperature changes.

Claims

1. Method of igniting gas generating pyrotechnic on signal from crash sensing means for supply and filling of an air cushion device including more than one ignitor for said pyrotechnic, comprising upon ambient temperature conditions surrounding an ignitor rising above a certain predetermined limit deactivating said last mentioned ignitor and reactivating the last mentioned ignitor when said temperature falls below a predetermined level, distributing ignition impulse for each of said ignitors from said sensing means, and igniting pyrotechnic by the activated ignitors.

2. A procEss as claimed in claim 1 further including placing switch means in circuit between the sensing means and said ignitor which may be deactivated for accomplishing deactivation of said ignitor.

3. A method as set forth in claim 1 including at least three ignitors, including said ignitors previously recited, further comprising deactivating at least another ignitor on ambient temperature reaching above a predetermined limit of relatively lower temperature than said first recited limit, and reactivating said just recited ignitor at a predetermined temperature level below the relatively lower temperature level.

4. A process as set forth in claim 3, said first mentioned ignitor which may deactivate deactivating at a temperature level above about 135*F. and reactivating at a temperature level below about 120*F. and said another ignitor deactivating at a temperature level above about 15*F. and reactivating at a temperature level below about 0*F.

5. A process as set forth in claim 4, the ignitors being in the form of a squib.

6. A process as set forth in claim 1, said last mentioned ignitor deactivating at a temperature level above about 135*F. and reactivating at a temperature level below about 120*F.

7. Apparatus for igniting gas generating pyrotechnic on signal from crash sensing means for supply and filling of an air cushion comprising more than one ignitor for initiating burning of said pyrotechnic, electrical connection from each of said ignitors to said sensing means to initiate burning of said ignitor to burn pyrotechnic and inflate the cushion, switch means connected to at least one of said ignitors to deactivate said at least one ignitor when ambient temperature conditions surrounding said ignitor rise above a certain predetermined limit and to reactivate said at least one ignitor when said temperature falls below a predetermined limit.

8. Apparatus as claimed in claim 7, said switch means in circuit between the sensing means and the ignitor, said switch means open to deactivate the ignitor and closed to reactive the ignitor.

9. Apparatus as claimed in claim 8, said switch means being a bimetallic diaphragm switch sensitive to temperature.

10. Apparatus as claimed in claim 7, including at least three ignitors, including said ignitors previously recited, second switch means operatively associated with at least one of said other ignitors, said second switch to deactivate said other ignator on ambient temperature reaching above a predetermined limit of relatively lower temperature than said earlier recited limit and to reactivate each of said first and second ignitors at a predetermined temperature level below the temperature level at which each is deactivated.

11. Apparatus as set forth in claim 10, said at least one first mentioned switch means opening to deactivate the associated ignitor at a temperature level above about 135*F. and to reactivate closing at a temperature level of below about 120*F. and said at least one second switch means opening to deactivate the associated ignition at a temperature level above about 15*F. and closing to reactivate at a temperature level of below about 0*F.

12. Apparatus as set forth in claim 11, the ignitors being in the form of a squib.

13. Apparatus as set forth in claim 11, said ignitors balanced about the steering shaft assembly on which they are mounted.