A fuel control device or fuel valve assembly includes a valve for metering flow of gaseous fuel to an engine, a drive device associated with the valve to adjust the effective flow area of the valve, a flow meter with at least one fixed area orifice located upstream of the valve, and one or more sens
A fuel control device or fuel valve assembly includes a valve for metering flow of gaseous fuel to an engine, a drive device associated with the valve to adjust the effective flow area of the valve, a flow meter with at least one fixed area orifice located upstream of the valve, and one or more sensors to measure predetermined parameters of the fuel flowing through the flow meter. A controller receives input from the flow sensor or sensors and a fuel demand signal from the engine control, calculates current flow rate based on the sensor inputs, and controls the drive device to adjust the valve flow area up or down depending on the difference between the calculated flow rate and current fuel demand signal.
대표청구항▼
1. A gaseous fuel control assembly comprising: a flow control valve housing having a gaseous fuel inlet, a metered gaseous fuel outlet for fuel supply to an engine, and a passageway between the gaseous fuel inlet and outlet;a flow control valve mounted in the passageway having an adjustable flow are
1. A gaseous fuel control assembly comprising: a flow control valve housing having a gaseous fuel inlet, a metered gaseous fuel outlet for fuel supply to an engine, and a passageway between the gaseous fuel inlet and outlet;a flow control valve mounted in the passageway having an adjustable flow area for metering flow of fuel to an engine;an adjustment device associated with the flow control valve to adjust the effective flow area of the valve;a flow measurement device having at least one fixed area orifice located upstream of the flow control valve, and at least one sensor associated with the orifice and configured to measure predetermined parameters of the fuel flowing through the orifice, the flow measurement device comprising a venturi secured in the passageway, the venturi having a fixed area inlet port, a reduced area throat downstream of the inlet port, and an outlet downstream of the throat; anda controller which receives input from the at least one sensor and a fuel demand signal from the engine, the controller having a processing module for calculating current flow rate based on the sensor input, a comparator module which compares the calculated flow rate with the fuel demand signal, and a valve control module which controls the adjustment device to adjust the flow area of the flow control valve up or down depending on the difference between the calculated current flow rate and current fuel demand signal;wherein the at least one sensor comprises at least one pressure sensor for sensing pressure of gas at the venturi throat, the venturi having an outer surface conforming to an opposing inner surface of the passageway along at least part of the length of the venturi, a throat pressure annulus between the outer surface of the venturi and inner surface of the passageway at a location surrounding the venturi throat, and a plurality of openings spaced around the venturi throat in communication with the throat pressure annulus, and the pressure sensor communicates with the throat pressure annulus to detect pressure at the venturi throat. 2. The assembly of claim 1, wherein the at least one sensor comprises a differential pressure sensor configured to detect pressure drop between the inlet port and throat of the venturi, a throat pressure sensor configured to detect absolute pressure of gaseous fuel flowing through the throat, and a temperature sensor configured to detect temperature of gaseous fuel flowing through the venturi, the controller receiving sensor inputs from the differential pressure sensor, the throat pressure sensor, and the temperature sensor, and the processing module being configured to determine current mass flow rate using the sensor inputs. 3. The assembly of claim 1, wherein the venturi has a smooth, curved inner surface extending from the inlet port to the throat, and a smooth outwardly tapering surface extending from the throat to the venturi outlet. 4. The assembly of claim 2, wherein the passageway has an outwardly tapering surface portion extending from the venturi outlet to the flow control valve. 5. The assembly of claim 4, wherein the outwardly tapering surface portion of the passageway has a taper angle less than the taper angle of the smooth outwardly tapering surface of the venturi. 6. The assembly of claim 4, wherein the angle of the outwardly tapering surface of the venturi is in the range from approximately five degrees to approximately twenty degrees. 7. The assembly of claim 6, wherein the angle of the outwardly tapering surface portion of the venturi is approximately 15 degrees. 8. The assembly of claim 1, wherein the at least one sensor further comprises a differential pressure sensor and first and second ports connecting the differential pressure sensor to an inlet region of the venturi and to the throat pressure annulus, respectively. 9. The assembly of claim 1, wherein the throat is located closer to the inlet port than the venturi outlet. 10. The assembly of claim 9, wherein the distance between the venturi outlet and the flow control valve is at least two inches. 11. The assembly of claim 10, wherein the distance between the throat of the venturi and the flow control valve is at least five inches. 12. The assembly of claim 1, wherein the venturi throat diameter is in the range from 0.25 inches to 1.15 inches. 13. The assembly of claim 3, wherein the venturi throat has a diameter of approximately 0.95 inches and the angle of the smooth outwardly tapering surface of the venturi is approximately 8.5 degrees. 14. The assembly of claim 3, wherein the venturi throat has a diameter of approximately 0.25 inches and the angle of the smooth outwardly tapering surface of the venturi is approximately 20 degrees. 15. The assembly of claim 1, wherein the flow control valve comprises a butterfly valve rotatably mounted in the passageway and the adjustment device comprises a drive motor configured to rotate the butterfly valve to vary the effective flow area. 16. A gaseous fuel control assembly comprising: a flow control valve housing having a gaseous fuel inlet, a metered gaseous fuel outlet for fuel supply to an engine, and a passageway between the gaseous fuel inlet and outlet;a flow control valve mounted in the passageway having an adjustable flow area for metering flow of fuel to an engine, the flow control valve comprising a butterfly valve rotatably mounted in the passageway;an adjustment device associated with the flow control valve to adjust the effective flow area of the valve, the adjustment device comprising a drive motor configured to rotate the butterfly valve to vary the effective flow area, the drive motor having a drive shaft;a flow measurement device having at least one fixed area orifice located upstream of the flow control valve, and at least one sensor associated with the orifice and configured to measure predetermined parameters of the fuel flowing through the orifice;a controller which receives input from the at least one sensor and a fuel demand signal from the engine, the controller having a processing module for calculating current flow rate based on the sensor input, a comparator module which compares the calculated flow rate with the fuel demand signal, and a valve control module which controls the drive motor to adjust the flow area of the butterfly valve up or down depending on the difference between the calculated current flow rate and current fuel demand signal;the butterfly valve comprising a disk and a butterfly shaft extending across the diameter of the disk and rotatably mounted across the passageway for rotation of the disk; anda coupler assembly which couples the drive shaft to the butterfly shaft and is configured to compensate for misalignment between the drive shaft and butterfly shaft. 17. The assembly of claim 16, wherein the coupler assembly has a first part having a central bore coupled to the drive shaft, a second part having a central bore coupled to the butterfly shaft, and spaced first and second connecting posts on opposite sides of the central bores which are loosely fitted in bores in the second part and first part, respectively, to compensate for misalignment between the drive shaft and butterfly shaft. 18. The assembly of claim 1, wherein the fixed area orifice comprises an orifice plate. 19. The assembly of claim 1, wherein the controller has an engine speed input for connection to an engine speed sensor, and the valve control module is further configured to adjust engine speed by control of the fuel input to the engine.
연구과제 타임라인
LOADING...
LOADING...
LOADING...
LOADING...
LOADING...
이 특허에 인용된 특허 (4)
Fisher, C. Ross; Fisher, David G.; Yates, Kristian W.; Hoie, William A., Emission control valve for gas-fueled engines.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.