US5746445A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Injection termination feature
Assignee: Autoliv ASP Inc
•
Filing: 1996-12-03
•
Granted: 1998-05-05
•
Expires: 2016-12-03
Abstract
Abstract In an inflator of a vehicle safety restraint system utilizing liquid propellant as the inflation gas generator, decomposition of residual liquid propellant within the inflator produces undesirable gases which can result in unacceptable inflator effluent. The injection termination features of the present invention are formed onto an encapsulation or plug of a regenerative piston inflator. Upon completion of the piston stroke, the injection termination feature makes contact with the injection ports and plugs the injection ports to prevent combustion and decomposition reactions from propagating through the piston.
Inventors
- 👤 Darrin L. Johnson
- 👤 Bradley D. Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:56
CPC Classifications
B; B60; B60R; B60R21/00; B60R21/02; B60R21/16; B60R21/26; B60R21/264
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
115 words
An inflator of a vehicle safety restraint system, comprising: a housing, the housing including a reservoir of liquid propellant; a combustion chamber disposed in the housing in communication with the liquid propellant reservoir; regenerative piston means for separating the liquid propellant reservoir and the combustion chamber, the piston means including a plurality of injection ports for delivering the liquid propellant to the combustion chamber in a controlled manner; and injection termination means disposed in the housing, wherein upon completion of a stroke of the piston means, the injection termination means seals the injection ports of the piston means for preventing combustion and decomposition reactions of any residual liquid propellant from propagating through the piston means.
Claim 2
Dependent Claim
115 words
An inflator of a vehicle safety restraint system, comprising: a housing, the housing including a reservoir of liquid propellant; a combustion chamber disposed in the housing in communication with the liquid propellant reservoir; regenerative piston means for separating the liquid propellant reservoir and the combustion chamber, the piston means including a plurality of injection ports for delivering the liquid propellant to the combustion chamber in a controlled manner; and injection termination means disposed in the housing, wherein upon completion of a stroke of the piston means, the injection termination means seals the injection ports of the piston means for preventing combustion and decomposition reactions of any residual liquid propellant from propagating through the piston means.
Claim 3
Dependent Claim
17 words
The inflator of claim 1, further comprising means for encapsulating the liquid propellant reservoir within the housing.
Claim 4
Dependent Claim
42 words
The inflator of claim 2, wherein the piston means comprises a piston including a head separating the combustion chamber from the liquid propellant reservoir and a piston stem extending through the encapsulation means, the piston being movably disposed within the encapsulation means.
Claim 5
Dependent Claim
61 words
The inflator of claim 3, further comprising a quantity of ignitor material disposed within the stem of the piston and initiating means disposed within the housing for igniting the material, wherein upon ignition the piston head is driven into the liquid propellant reservoir and the liquid propellant flows through the injection ports disposed in the piston head into the combustion chamber.
Claim 6
Dependent Claim
25 words
The inflator of claim 3, wherein the encapsulation means comprises an encapsulation cup contacting the housing, the encapsulation cup being molded from a non-corrosive material.
Claim 7
Dependent Claim
16 words
The inflator of claim 5, wherein the injection termination means is located within the encapsulation cup.
Claim 8
Dependent Claim
42 words
The inflator of claim 6, wherein the injection termination means comprises a plurality of buttons of material molded integrally with the encapsulation cup, wherein upon completion of the stroke of the piston the plurality of buttons seal the plurality of injection ports.
Claim 9
Dependent Claim
41 words
The inflator of claim 6, wherein the injection termination means comprises a plurality of buttons of material adhered to the encapsulation cup, wherein upon completion of the stroke of the piston the plurality of buttons seal the plurality of injection ports.
Claim 10
Dependent Claim
28 words
The inflator of claim 6, wherein the piston head includes a circular groove in a bottom portion thereof, the plurality of injection ports being disposed in the groove.
Claim 11
Dependent Claim
46 words
The inflator of claim 9, wherein the injection termination means comprises a ring of material located on the encapsulation cup, wherein upon completion of the stroke of the piston, the ring fits within the groove of the piston head to seal the plurality of injection ports.
Claim 12
Dependent Claim
37 words
The inflator of claim 6, wherein the injection termination means comprises a washer of material disposed within the encapsulation cup, wherein upon completion of the stroke of the piston, the washer seals the plurality of injection ports.
Claim 13
Dependent Claim
19 words
The inflator of claim 3, wherein the encapsulation means comprises an encapsulation tube of non-corrosive material contacting the housing.
Claim 14
Dependent Claim
16 words
The inflator of claim 12, wherein the encapsulation tube includes a cap sealing an end thereof.
Claim 15
Dependent Claim
49 words
The inflator of claim 13, wherein the injection termination means comprises a plurality of buttons of material molded integrally with the cap of the encapsulation tube, wherein upon completion of the stroke of the piston the plurality of buttons seal the plurality of injection ports in the piston head.
Claim 16
Dependent Claim
48 words
The inflator of claim 13, wherein the injection termination means comprises a plurality of buttons of material adhered to the cap of the encapsulation tube, wherein upon completion of the stroke of the piston the plurality of buttons seal the plurality of injection ports of the piston head.
Claim 17
Dependent Claim
28 words
The inflator of claim 13, wherein the piston head includes a circular groove in a bottom portion thereof, the plurality of injection ports being disposed in the groove.
Claim 18
Dependent Claim
53 words
The inflator of claim 16, wherein the injection termination means comprises a ring of material located on the cap of the encapsulation tube, wherein upon completion of the stroke of the piston, the ring fits within the groove of the piston head to seal the plurality of injection ports of the piston head.
Claim 19
Dependent Claim
66 words
The inflator of claim 6, wherein the injection termination means comprises a chamber of non-combustible material located within the encapsulation cup, the chamber being separated from the liquid propellant reservoir by a frangible membrane, wherein upon completion of the stroke of the piston, the piston head fractures the membrane and the non-combustible material flows into and seals the plurality of injection ports of the piston head.
Claim 20
Independent Claim
151 words
A method of terminating injection of a liquid propellant in a regenerative piston inflator of a vehicle safety restraint system, comprising the steps of: movably positioning a piston within a housing of the inflator, the housing including a reservoir of liquid propellant and a combustion chamber separated from the liquid propellant reservoir by a head of the piston; driving the piston head into the liquid propellant reservoir, the piston head including a plurality of injection ports in fluid communication with the liquid propellant reservoir, the liquid propellant flowing through the injection ports into the combustion chamber; combusting the liquid propellant in the combustion chamber; continuing to drive the piston into the liquid propellant reservoir; and sealing the injection ports of the piston head by injection termination means disposed in the housing to prevent combustion and decomposition reactions of any remaining liquid propellant from propagating through the injection ports of the piston.
Claim 21
Independent Claim
151 words
A method of terminating injection of a liquid propellant in a regenerative piston inflator of a vehicle safety restraint system, comprising the steps of: movably positioning a piston within a housing of the inflator, the housing including a reservoir of liquid propellant and a combustion chamber separated from the liquid propellant reservoir by a head of the piston; driving the piston head into the liquid propellant reservoir, the piston head including a plurality of injection ports in fluid communication with the liquid propellant reservoir, the liquid propellant flowing through the injection ports into the combustion chamber; combusting the liquid propellant in the combustion chamber; continuing to drive the piston into the liquid propellant reservoir; and sealing the injection ports of the piston head by injection termination means disposed in the housing to prevent combustion and decomposition reactions of any remaining liquid propellant from propagating through the injection ports of the piston.
Claim 22
Dependent Claim
46 words
The method of claim 19, wherein the injection termination means comprises a quantity of material disposed within an encapsulation means enclosing the liquid propellant, and the step of sealing the injection ports of the piston head comprises sealing the injection ports with the quantity of material.
References Cited (Backward Citations)
US3618974A
Cited
US3689105A
Cited
US3690255A
Cited
US3960390A
Cited
US4326377A
Cited
US4805399A
Cited
US5060973A
Cited
US5330730A
Cited
US5345876A
Cited
US5487561A
Cited
US5639117A
Cited
US5669631A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-05-04 | 2001-11-03 | 2002-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-04 | 2005-11-03 | 2006-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-04 | 2009-11-03 | 2010-05-05 | $7700.00 | Window Closed / Lapsed |