US4151710A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lubrication cooling system for aircraft engine accessory
Assignee: RTX Corp
•
Filing: 1977-03-11
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Granted: 1979-05-01
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Expires: 1997-03-11
Abstract
Abstract This invention serves to cool the lubricant used by a mechanical constant speed drive (CSD) driving an aircraft alternator which aircraft is powered by a turbofan engine. The system cooling capacity is supplemented by an existing engine fuel/oil heat exchanger thereby effectuating a reduction in size of the CSD fan air/oil heat exchanger and minimizing an aircraft engine performance penalty.
Inventors
- 👤 James G. Griffin
- 👤 Irwin D. Singer
- 👤 Roger L. Summers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:47
CPC Classifications
F; F02; F02C; F02C7/00; F02C7/12; F02C7/14; Y; Y02; Y02T; Y02T50/00; Y02T50/60
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
177 words
Lubrication system for a constant speed drive mechanically driven by a turbofan engine having a fuel to lubricant heat exchanger for cooling the engine lubricant with the engine's fuel prior to combustion by indirect heat exchange relation, a cooling system for the lubricant of the constant speed drive including a plate/fin heat exchanger for indirect heat exchange of the lubricant and fan air mounted on the fan duct and extending in the fan air stream, a cooling loop for the lubricant of the constant speed drive including an extension of said fuel to lubricant heat exchanger for indirect heat exchange of said constant speed drive lubricant and engine fuel, thereby minimizing the size of the fan mounted plate/fin heat exchanger and improving engine performance, said cooling loop includes conduit means for directing said lubricant to said fuel to lubricant heat exchanger, and means to separate said lubricant for the constant speed drive from the engine lubricant such that the lubricant for the constant speed drive is downstream of the engine lubricant relative to the flow of fuel.
Claim 2
Dependent Claim
177 words
Lubrication system for a constant speed drive mechanically driven by a turbofan engine having a fuel to lubricant heat exchanger for cooling the engine lubricant with the engine's fuel prior to combustion by indirect heat exchange relation, a cooling system for the lubricant of the constant speed drive including a plate/fin heat exchanger for indirect heat exchange of the lubricant and fan air mounted on the fan duct and extending in the fan air stream, a cooling loop for the lubricant of the constant speed drive including an extension of said fuel to lubricant heat exchanger for indirect heat exchange of said constant speed drive lubricant and engine fuel, thereby minimizing the size of the fan mounted plate/fin heat exchanger and improving engine performance, said cooling loop includes conduit means for directing said lubricant to said fuel to lubricant heat exchanger, and means to separate said lubricant for the constant speed drive from the engine lubricant such that the lubricant for the constant speed drive is downstream of the engine lubricant relative to the flow of fuel.
Claim 3
Dependent Claim
26 words
A lubrication system as in claim 1 including a bypass means for bypassing said plate/fin heat exchanger when said lubricant goes below a predetermined temperature value.
Claim 4
Dependent Claim
26 words
A lubrication system as in claim 2 including another bypass means for bypassing said fuel to lubricant heat exchanger whenever said temperature reaches a predetermined condition.
Claim 5
Dependent Claim
37 words
A lubrication system as in claim 1 wherein said fuel to lubricant heat exchanger includes a plurality of axially extending tubes for conducting the flow of fuel prior to being delivered to the combustor of said engine.
References Cited (Backward Citations)
US2865580A
Cited
US3797561A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-04-30 | 1982-10-30 | 1983-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-30 | 1986-10-30 | 1987-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-30 | 1990-10-30 | 1991-05-01 | $7700.00 | Window Closed / Lapsed |