Altitude fuel limiter for engine and method of using the same

Patent metadata

Field	Value
Publication number	US-9765708-B2
Application number	US-201414536762-A
Country	US
Kind code	B2
Filing date	Nov 10, 2014
Priority date	Nov 19, 2013
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

An altitude fuel limiter and method for controlling an engine using the same is provided. The altitude fuel limiter includes a torque screw sleeve extending from an inboard end to an outboard end. The torque screw sleeve has an interior surface defining a central bore extending axially within the torque screw sleeve. A plunger is disposed within the central bore and moves axially between a first position and a second position. A plunger regulator senses ambient pressure and is coupled with the plunger to axially displace the plunger toward the inboard end of the torque screw sleeve to the first position in response to sensing an ambient pressure that is below a predetermined pressure. The predetermined pressure may be associated with non-compliant altitudes and the plunger limits fuel delivered to the engine when displaced to the first position.

First claim

What is claimed is:

1. An altitude fuel limiter for an engine, comprising:
a torque screw sleeve extending from an inboard end to an outboard end and including an interior surface defining a central bore extending axially within said torque screw sleeve;
a plunger disposed within said central bore of said torque screw sleeve, said plunger being movable along an axial direction between a first position and a second position; and
a plunger regulator coupled with said plunger, sensing ambient pressure, and axially displacing said plunger toward said inboard end of said torque screw sleeve to said first position to limit fuel delivered to the engine in response to said plunger regulator sensing an ambient pressure that is below a predetermined pressure, wherein said first position of said plunger is defined by said plunger at least partially extending from said inboard end of said torque screw sleeve to engage a governor lever arm of the engine for limiting a maximum fuel flow delivered to the engine by restricting rotational travel of said governor lever arm.

2. The altitude fuel limiter as set forth in claim 1 wherein said plunger regulator axially displaces said plunger toward said outboard end of said torque screw sleeve to said second position for providing unlimited fuel delivery to the engine in response to sensing an ambient pressure that is above said predetermined pressure.

3. The altitude fuel limiter as set forth in claim 2 wherein said second position of said plunger is defined by said plunger being displaced toward said outboard end of said torque screw sleeve relative to said first position of said plunger.

4. The altitude fuel limiter as set forth in claim 1 wherein said predetermined pressure corresponds with ambient pressure at an altitude of 2,500 feet above sea level.

5. The altitude fuel limiter as set forth in claim 1 wherein said predetermined pressure corresponds with ambient pressure at an altitude of 3,500 feet above sea level.

6. The altitude fuel limiter as set forth in claim 1 wherein said plunger regulator is an aneroid barometer.

7. The altitude fuel limiter as set forth in claim 1 wherein said plunger regulator includes a barometric pressure sensor for sensing ambient pressure and a solenoid in communication with said barometric pressure sensor and coupled with said plunger for axially displacing said plunger.

8. The altitude fuel limiter as set forth in claim 1 further comprising:
a sealing cap disposed about and enveloping said outboard end of said torque screw sleeve and said plunger regulator for preventing tampering with said torque screw sleeve and said plunger regulator.

9. An altitude fuel limiter for an engine, comprising:
a torque screw sleeve extending from an inboard end to an outboard end and including an interior surface defining a central bore extending axially within said torque screw sleeve;
a plunger disposed within said central bore of said torque screw sleeve, said plunger being movable along an axial direction between a first position and a second position; and
a plunger regulator coupled with said plunger, sensing ambient pressure, and axially displacing said plunger toward said inboard end of said torque screw sleeve to said first position to limit fuel delivered to the engine in response to said plunger regulator sensing an ambient pressure that is below a predetermined pressure, wherein said interior surface of said torque screw sleeve has a threaded portion proximate to said outboard end said torque screw sleeve.

10. The altitude fuel limiter as set forth in claim 9 further comprising:
a plunger housing of tubular shape extending between an inboard end and an outboard end and including an inner surface defining a plunger bore having a predetermined diameter and an outer surface having a threaded portion for engagement with said threaded portion of said interior surface of said torque screw sleeve.

11. The altitude fuel limiter as set forth in claim 10 wherein said plunger includes an annular stop and an inboard portion of cylindrical shape extending axially from said annular stop toward said inboard end of said torque screw sleeve and an outboard portion of cylindrical shape extending axially from said annular stop toward said outboard end of said torque screw sleeve.

12. The altitude fuel limiter as set forth in claim 11 wherein said plunger has a first diameter at said annular stop and a second diameter at said outboard portion that is less than said first diameter of said annular stop and less than said predetermined diameter of said plunger bore to provide sliding engagement of said outboard portion of said plunger within said plunger bore of said plunger housing.

13. The altitude fuel limiter as set forth in claim 12 wherein said plunger has a third diameter at said inboard portion that is less than said first diameter of said annular stop.

14. The altitude fuel limiter as set forth in claim 13 wherein said third diameter of said inboard portion of said plunger is equal to said second diameter of said outboard portion of said plunger.

15. The altitude fuel limiter as set forth in claim 13 further comprising:
an inboard spring disposed within said central bore of said torque screw sleeve and annularly about said inboard portion of said plunger.

16. The altitude fuel limiter as set forth in claim 15 further comprising:
an outboard spring disposed within said plunger bore of said plunger housing and annularly about said outboard portion of said plunger.

17. The altitude fuel limiter as set forth in claim 16 wherein said inboard spring and said outboard spring abut said annular stop of said plunger in an opposing relationship for axially biasing said plunger to said second position.

18. The altitude fuel limiter as set forth in claim 17 wherein said torque screw sleeve has a tubular shape and an exterior surface, said exterior surface of said torque screw sleeve being smooth proximate to said inboard end of said torque screw sleeve for sliding engagement with a governor assembly and said exterior surface of said torque screw sleeve including a threaded portion proximate to said outboard end of said torque screw sleeve for threaded engagement with said governor assembly.

19. The altitude fuel limiter as set forth in claim 18 wherein said torque screw sleeve includes a head portion abutting said outboard end of said torque screw sleeve including a plurality of flat perimeter faces circumscribing said head portion for tool engagement.

20. The altitude fuel limiter as set forth in claim 19 further comprising:
a lock nut having a threaded bore extending axially through said lock nut for engaging said threaded portion of said outer surface of said plunger housing, said lock nut being disposed on said plunger housing between said inboard end of said plunger housing and said outboard end of said plunger housing for abutting engagement with said head portion of said torque screw sleeve and said lock nut including a plurality of flat faces circumscribing said lock nut for tool engagement.

21. The altitude fuel limiter as set forth in claim 20 further comprising:
a stepped nut including a threaded bore extending axially through said stepped nut for engaging said threaded portion of said exterior surface of said torque screw sleeve, said stepped nut being disposed on said torque screw sleeve between said inboard end of said torque screw sleeve and said outboard end said torque screw sleeve for abutting engagement with said governor a

Assignees

• Avl Powertrain Engineering Inc

Inventors

• Kulp David L

Classifications

• F02D33/006

  depending on engine operating conditions, e.g. start, stop or ambient conditions · CPC title

• F02D2200/703

  Atmospheric pressure · CPC title

• F02M7/20 Primary

  operated automatically, e.g. dependent on altitude · CPC title

• F02M37/0023

  Valves in the fuel supply and return system · CPC title

• F02D2250/38

  Control for minimising smoke emissions, e.g. by applying smoke limitations on the fuel injection amount · CPC title