US3691730A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel tank inerting system
Assignee: Parker Hannifin Corp
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Filing: 1971-05-18
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Granted: 1972-09-19
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Expires: 1991-05-18
Abstract
Abstract A fuel tank inerting system in which the tank ullage contains a non-combustible gaseous mixture of fuel vapor, oxygen and an inert gas, such mixture from the ullage being circulated through incoming liquid fuel when the tank is being filled for scrubbing dissolved oxygen from the fuel and diluting the same as it rises to the tank ullage, and there being a means for introducing a fresh supply of inert gas from a separate source for continuing the scrubbing and diluting of oxygen from the incoming fuel only when the oxygen content of the tank ullage nears a predetermined yet non-combustible percentage, whereby a minimum amount of fresh inert gas is utilized for maintaining the ullage gases incombustible during filling of the tank and during subsequent ascending flight of the aircraft.
Inventors
- 👤 William G Hickey
- 👤 Richard L Kenyon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:58
CPC Classifications
B; B64; B64D; B64D37/00; B64D37/32
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
103 words
An inerting system comprising a fuel tank whose ullage contains a sufficient supply of inert gas whereby the oxygen content of the ullage is below an amount that would support combustion of fuel vapor therein, a separate supply of inert fluid connected to the tank, first means for introducing liquid fuel into the tank for filling the same, second means for mixing said inert ullage gas with said incoming fuel to remove oxygen from the fuel, and third means for automatically initiating flow of said inert fluid to said tank when a predetermined amount of liquid fuel has been supplied to the tank.
Claim 2
Dependent Claim
103 words
An inerting system comprising a fuel tank whose ullage contains a sufficient supply of inert gas whereby the oxygen content of the ullage is below an amount that would support combustion of fuel vapor therein, a separate supply of inert fluid connected to the tank, first means for introducing liquid fuel into the tank for filling the same, second means for mixing said inert ullage gas with said incoming fuel to remove oxygen from the fuel, and third means for automatically initiating flow of said inert fluid to said tank when a predetermined amount of liquid fuel has been supplied to the tank.
Claim 3
Dependent Claim
29 words
The system of claim 1 in which there is a means for automatically stopping flow of said inert fluid to the tank when the latter is full of fuel.
Claim 4
Dependent Claim
47 words
The system of claim 1 in which said second means includes a valve controlled conduit connecting the ullage with the incoming liquid fuel and there is a fourth means that automatically causes the valve to close when a predetermined amount of liquid fuel has entered the tank.
Claim 5
Dependent Claim
40 words
The system of claim 1 in which said third means is automatically actuated by a float operated device to permit flow of said inert fluid into the tank when the liquid fuel has reached a predetermined level in the tank.
Claim 6
Dependent Claim
32 words
The system of claim 1 in which there is a means for automatically discontinuing flow of said inert fluid to the tank when flow of liquid fuel to the tank is discontinued.
Claim 7
Dependent Claim
37 words
The system of claim 1 in which there are means for automatically shutting off flow of incoming liquid fuel and flow of said inert fluid into the tank when the tank is substantially full of liquid fuel.
Claim 8
Dependent Claim
89 words
An inerting system comprising a fuel tank containing an inert gas in its ullage, first means including a first conduit for delivering liquid fuel from a supply source to said tank for filling the latter with the liquid fuel, second means including a second conduit for delivering inert fluid to the tank from a source other than the tank ullage, a third conduit connecting the ullage to the first conduit, and third means responsive to a predetermined level of liquid fuel in the tank for opening the second conduit.
Claim 9
Dependent Claim
89 words
An inerting system comprising a fuel tank containing an inert gas in its ullage, first means including a first conduit for delivering liquid fuel from a supply source to said tank for filling the latter with the liquid fuel, second means including a second conduit for delivering inert fluid to the tank from a source other than the tank ullage, a third conduit connecting the ullage to the first conduit, and third means responsive to a predetermined level of liquid fuel in the tank for opening the second conduit.
Claim 10
Dependent Claim
31 words
The system of claim 7 in which said third means includes a valve actuated by a float operated device responsive to said predetermined level to cause closing of said third conduit.
Claim 11
Dependent Claim
24 words
The system of claim 7 in which said third means includes a float operated valve that closes the third conduit at said predetermined level.
Claim 12
Dependent Claim
22 words
The system of claim 7 in which said first conduit includes an aspirator and said third conduit is connected to the aspirator.
Claim 13
Dependent Claim
16 words
The system of claim 7 in which said second conduit is also connected to said aspirator.
Claim 14
Dependent Claim
19 words
The system of claim 11 in which said second conduit is connected to the aspirator via said third conduit.
Claim 15
Dependent Claim
36 words
The system of claim 7 in which said third means includes a float operated switch responsive to said predetermined level to cause opening of said second conduit and which also causes closing of said third conduit.
Claim 16
Dependent Claim
24 words
The system of claim 7 in which said third means is actuated upon the tank becoming filled to about 55 percent of its capacity.
Claim 17
Dependent Claim
59 words
The system of claim 8 in which there is a normally closed valve in said second conduit, means causing a lowering of fluid pressure within said third conduit when said float actuated valve closes, and there is a pressure differential operated device responsive to said lowering of fluid pressure in said third conduit for opening said normally closed valve.
Claim 18
Dependent Claim
20 words
The system of claim 7 in which said third conduit is always open to an upper region of the tank.
Claim 19
Dependent Claim
69 words
The system of claim 7 in which there is a supply of inert fluid in the aircraft connected by a fourth conduit to The tank, and there is a means actuated by a predetermined differential in pressure between the interior and exterior of the tank for opening the fourth conduit for introducing inert fluid from said supply in the aircraft to the tank when the aircraft descends in altitude.
Claim 20
Dependent Claim
30 words
The system of claim 7 in which there are automatically operated means for closing off both the supply of liquid fuel and inert fluid when the tank is substantially full.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-19 | 1976-03-20 | 1976-09-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-19 | 1980-03-20 | 1980-09-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-19 | 1984-03-20 | 1984-09-19 | $7700.00 | Window Closed / Lapsed |