Sequencing system for variable level output inflators

• US 5,880,534 A
• Filed: 07/16/1997
• Issued: 03/09/1999
• Est. Priority Date: 07/16/1997
• Status: Expired due to Fees

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Inventors: Clark, Marcus T., Mossi, G. Dean
• Primary Examiner(s): Elms, Richard T.
• Application Number:
  US08/895,011
• Time in Patent Office: 601 Days
• Field of Search: 307/10.1, 307/9.1, 307/121, 180/282, 180/271, 280/729, 280/734-736, 280/741, 340/436, 340/438, 340/669, 701/36, 701/45-47, 102/202.5, 102/202.6, 102/202, 102/275.11, 102/276
• US Class Current: 307/10.1
• CPC Class Codes: B60R 2021/2633 with a plurality of inflation levels
• CPC Class Codes: B60R 2021/2725 using a fluid fuel gas generator
• CPC Class Codes: B60R 21/017 including arrangements for providing electric power to safety arrangements or their actuating means, e.g. to pyrotechnic fuses or electro-mechanic valves
• CPC Class Codes: B60R 21/272 with means for increasing the pressure of the gas just before or during liberation, e.g. hybrid inflators

Abstract

A sequencing system is provided for varying the output of an inflator in a vehicle safety restraint system. The inflator has a housing including at least one combustion chamber. Gas generant for producing an inflation gas is disposed in the housing. Ignition material for igniting the gas generating means is disposed in the at least one combustion chamber. A first electric squib is disposed in the inflator housing for initially igniting the ignition material. At least one additional electric squib is disposed in the inflator housing for further igniting the ignition material. A delay sequencing unit is disposed outside of the inflator housing for activating the at least one additional electric squib after a predetermined time from the activation of the first electric squib. Upon activation of the first electric squib by an electrical pulse, an initial amount of inflation gas is generated and the electrical pulse is also received by the delay sequencing unit. After the predetermined time the electrical pulse is allowed to flow to the at least one additional electric squib and an additional amount of inflation gas is generated.

Claims

1. A sequencing system for varying the output of an inflator in a vehicle safety restraint system, comprising:

an inflator having a housing, the housing including at least one combustion chamber;

means for generating an inflation gas disposed in the housing;

ignition means disposed in the at least one combustion chamber for igniting the gas generating means;

a first electrical squib disposed in the inflator housing for initially igniting the ignition means;

at least one additional electric squib disposed in the inflator housing for further igniting the ignition means; and

a delay sequencing unit, including a negative temperature coefficient thermistor, disposed outside of the inflator housing for activating said at least one additional electric squib after a predetermined time from the activation of the first electric squib, wherein upon activation of the first electric squib by an electrical pulse an initial amount of inflation gas is generated and the electrical pulse is delivered to the delay sequencing unit and after the predetermined time the electrical pulse is forwarded to the at least one additional electrical squib and an additional amount of inflation gas is generated.

2. A sequencing system for varying the output of an inflator in a vehicle safety restraint system, comprising:

an inflator having a housing, the housing including at least one combustion chamber;

means for generating an inflation gas disposed in the housing;

ignition means disposed in the at least one combustion chamber for igniting the gas generating means;

a first electrical squib disposed in the inflator housing for initially igniting the ignition means;

at least one additional electric squib disposed in the inflator housing for further igniting the ignition means; and

a delay sequencing unit, including a relay, disposed outside of the inflator housing for activating said at least one additional electric squib after a predetermined time from the activation of the first electric squib, wherein upon activation of the first electric squib by an electrical pulse an initial amount of inflation gas is generated and the electrical pulse is delivered to the delay sequencing unit and after the predetermined time the electrical pulse is forwarded to the at least one additional electrical squib and an additional amount of inflation gas is generated.