Patent US4864813A successfully refreshed from Google Patents.
US4864813A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for a gas turbine engine
Assignee: RTX Corp
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Filing: 1988-05-23
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Granted: 1989-09-12
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Expires: 2008-05-23
Abstract
Abstract When a stall is dectected during high power operation, the engine is given one chance to recover without a change in bleed schedule. Should a record stall occur within 10 seconds the control system switches to an override bleed schedule for 51/2 minutes, or until throttle is reduced. This supplies a minimum adaquate thrust for a limited time.
Inventors
- 👤 Leon Krukoski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:26
CPC Classifications
F; F04; F04D; F04D27/00; F04D27/02; F04D27/0207; F04D27/023; F04D27/0223
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
160 words
A foreign object damage control system for an aircraft gas turbine engine comprising: stall detector means; bleed valve postion detecting means; first setting means for setting a first flag in response to a detected stall; a second setting means for setting a second flag in response to a detected recovery from stall, but only in the presence of said first flag; a timer; means for starting said timer in response to the setting of said second flag; third setting means for setting a third flag in response to a detected stall during a preselected first time period of the time cycle of said timer; reset means for resetting said third flag in response to a detected stall not occurring during the first period of the time cycle of said timer; a normal bleed schedule; an override bleed schedule; and means for replacing said normal bleed schedule with said override bleed schedule in response to the setting of said third flag.
Claim 2
Dependent Claim
160 words
A foreign object damage control system for an aircraft gas turbine engine comprising: stall detector means; bleed valve postion detecting means; first setting means for setting a first flag in response to a detected stall; a second setting means for setting a second flag in response to a detected recovery from stall, but only in the presence of said first flag; a timer; means for starting said timer in response to the setting of said second flag; third setting means for setting a third flag in response to a detected stall during a preselected first time period of the time cycle of said timer; reset means for resetting said third flag in response to a detected stall not occurring during the first period of the time cycle of said timer; a normal bleed schedule; an override bleed schedule; and means for replacing said normal bleed schedule with said override bleed schedule in response to the setting of said third flag.
Claim 3
Dependent Claim
34 words
An apparatus as in claim 1 having also: means for returning to said normal bleed schedule in response to the expiration of a pre-established second time period of the time cycle of said timer.
Claim 4
Dependent Claim
28 words
An apparatus as in claim 1 having also: means for blocking said first setting means in response to the detection of said bleed valves being not substantially open.
Claim 5
Dependent Claim
30 words
An apparatus as in claim 1 having also: means for blocking said third setting means in response to the detection of said bleed valves being greater than 25 percent open.
Claim 6
Dependent Claim
31 words
An apparatus as in claim 1 having also: means for detecting throttle position; and means for returning to said normal bleed schedule in response to detection of a low throttle position.
Claim 7
Dependent Claim
73 words
An apparatus as in claim 1 having also: means for blocking said first setting means in response to the detection of said bleed valves being not substantially open; means for blocking said third setting means in response to the detection of said bleed valves being greater than 25 percent open; means for detecting throttle position; and means for returning to said normal bleed schedule in response to detection of a low throttle position.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-09-11 | 1993-03-13 | 1993-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-09-11 | 1997-03-13 | 1997-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-09-11 | 2001-03-13 | 2001-09-12 | $7700.00 | Window Closed / Lapsed |