SYSTEM AND METHOD FOR DETECTING PRESSURE VARIATIONS IN FUEL DISPENSERS TO MORE ACCURATELY MEASURE FUEL DELIVERED

• US 20080257429A1
• Filed: 04/20/2007
• Published: 10/23/2008
• Est. Priority Date: 04/20/2007
• Status: Active Grant

• Current Assignee: Gilbarco Incorporated (Vontier Corp.)
• Original Assignee: Gilbarco Incorporated (Vontier Corp.)
• Inventors: Nanaji, Seifollah S., Robertson, Philip A.
• Granted Patent: US 7,681,460 B2
• Time in Patent Office: Days
• US Class Current: 137/557
• CPC Class Codes: B67D 7/16 Arrangements of liquid meters
• CPC Class Codes: G07F 13/025 wherein the volume is determined during delivery
• CPC Class Codes: Y10T 137/8326 Fluid pressure responsive indicator, recorder or alarm

Abstract

A system and method for enhancing the accuracy of fuel flow measurement by a fuel dispenser are provided. Pressure sensors positioned in the fuel flow path detect pressure in the fuel flow path and communicate pressure signals to a control system in the fuel dispenser. The pressure signals are used by the control system to enhance the accuracy of the fuel flow rate and fuel dispensed that the control system determines by converting meter signals from a meter. In particular, the pressure signals are used by the control system to determine whether a non-steady state condition exists in the fuel flow path and compensate the fuel flow rate and fuel dispensed due to the non-steady state condition.

Claims

1. A fuel dispenser for dispensing fuel from fuel storage tanks into a vehicle, comprising:

a control system;

a fuel flow path to receive fuel from the fuel storage tanks for dispensing to the vehicle;

a meter coupled inline to the fuel flow path and through which fuel passes and adapted to generate a meter signal in relation to the amount of fuel passing through the meter to the control system; and

a pressure sensor positioned in the fuel flow path that senses pressure in the fuel flow path and communicates a pressure signal associated with the pressure sensed to the control system;

the control system adapted to;

receive the meter signal from the meter;

calculate a volume or flow rate of the fuel delivered to the vehicle based on the meter signal;

detect if a non-steady state condition exists in the fuel flow path based on the pressure signal received from the pressure sensor; and

compensate the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition.

2. The fuel dispenser of claim 1, wherein the control system is further adapted to compensate the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition by disregarding the meter signal for a predetermined period of time.

3. The fuel dispenser of claim 2, wherein the control system is further adapted to resume calculating a volume or flow rate of the fuel delivered to the vehicle based on the meter signal after expiration of the predetermined period of time.

4. The fuel dispenser of claim 1, wherein the control system is further adapted to compensate the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition by applying a mathematical factor to the calculated volume or flow rate of the fuel.

5. The fuel dispenser of claim 1, wherein the detection of the non-steady state condition is based on a detection of a pressure spike in the fuel flow path.

6. The fuel dispenser of claim 1, wherein the non-steady state condition is due to a nozzle snap.

7. The fuel dispenser of claim 6, wherein the nozzle snap is a local nozzle snap.

8. The fuel dispenser of claim 6, wherein the nozzle snap is a remote nozzle snap.

9. The fuel dispenser of claim 1, wherein the pressure sensor is positioned in the fuel flow path downstream from the meter.

10. The fuel dispenser of claim 1, wherein the pressure sensor is positioned upstream from the meter.

11. The fuel dispenser of claim 1 further comprising:

a first pressure sensor positioned in the fuel flow path downstream from the meter that senses pressure in the fuel flow path and communicates a first pressure signal associated with the pressure sensed to the control system; and

a second pressure sensor positioned in the fuel flow path upstream from the meter that senses pressure in the fuel flow path and communicates a second pressure signal associated with the pressure sensed to the control system;

the control system adapted to;

receive the meter signal from the meter;

calculate a volume or flow rate of the fuel delivered to the vehicle based on the meter signal;

detect if a non-steady state condition exists in the fuel flow path based on at least one of the first pressure signal received from the first pressure sensor and the second pressure signal received from the second pressure sensor; and

compensate the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition.

12. The fuel dispenser of claim 11, wherein the control system is further adapted to compensate the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition by disregarding the meter signal for a predetermined period of time.

13. The fuel dispenser of claim 11, wherein the control system is further adapted to resume calculating a volume or flow rate of the fuel delivered to the vehicle based on the meter signal after expiration of the predetermined period of time.

14. The fuel dispenser of claim 11, wherein the control system is further adapted to compensate the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition by applying a mathematical factor to the calculated volume or flow rate of the fuel.

15. The fuel dispenser of claim 11, wherein the detection of the non-steady state condition is based on a detection of a pressure spike by at least one of the first pressure sensor and second pressure sensor in the fuel flow path.

16. The fuel dispenser of claim 11, wherein the control system compares the first pressure signal associated with the pressure sensed by the first pressure sensor with the second pressure signal associated with the pressure sensed by the second pressure sensor and from the comparison determines whether a non-steady state condition exists in the fuel flow path.

17. The fuel dispenser of claim 16, wherein the control system determines from the comparison of the first pressure signal with the second pressure signal that a local nozzle snap caused the non-steady state condition.

18. The fuel dispenser of claim 16, wherein the control system determines from the comparison of the first pressure signal with the second pressure signal that a remote nozzle snap caused the non-steady state condition.

19. The fuel dispenser of claim 16, wherein the control system is further adapted to compensate the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition by disregarding the meter signal for a predetermined period of time and wherein the predetermined period of time is based on the comparison of the first pressure signal associated with the pressure sensed by the first pressure sensor with the second pressure signal associated with the pressure sensed by the second pressure sensor.

20. The fuel dispenser of claim 16, wherein the non-steady state condition is a reversal of fuel flow in the fuel flow path.

21. The fuel dispenser of claim 16 further comprising:

a third pressure sensor positioned in the fuel flow path upstream from the meter that senses pressure in the fuel flow path and communicates a third pressure signal associated with the pressure sensed to the control system;

the control system adapted to;

receive the meter signal from the meter;

receive at least one of the first pressure signal received from the first pressure sensor, the second pressure signal received from the second pressure sensor, and third signal from the third pressure sensor; and

calculate a volume or flow rate of the fuel delivered to the vehicle based on the meter signal and the at least one of the first pressure signal, the second pressure signal and the third pressure signal.

22. A method for dispensing fuel received from fuel storage tanks into a vehicle, comprising:

receiving from a meter a meter signal in relation to the amount of fuel passing through the meter;

calculating a volume or flow rate of the fuel dispensed to the vehicle based on the meter signal;

detecting a non-steady state condition in the fuel flow path based on a pressure signal received from a pressure sensor positioned in the fuel flow path; and

compensating the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition.

23. The method of claim 22, wherein compensating the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition comprises disregarding the meter signal for a predetermined period of time.

24. The method of claim 23 further comprising resuming calculating a volume or flow rate of the fuel dispensed to the vehicle based on the meter signal after expiration of the predetermined period of time.

25. The method of claim 22, wherein compensating the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition comprises applying a mathematical factor to the calculated volume or flow rate of the fuel.

26. The method of claim 22, wherein detecting a non-steady state condition in the fuel flow path comprises detecting a pressure spike in the fuel flow path.

27. The method of claim 22, wherein the pressure sensor is positioned downstream from the meter.

28. The method of claim 22, wherein the pressure sensor is positioned upstream from the meter.

29. The method of claim 22 further comprising:

detecting a non-steady state condition in the fuel flow path based on at least one of a first pressure signal received from a first pressure sensor positioned in the fuel flow path downstream from the meter and a second pressure signal received from a second pressure sensor positioned in the fuel flow path upstream from the meter;

compensating the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition.

30. The method of claim 29, wherein compensating the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition comprises disregarding the meter signal for a predetermined period of time.

31. The method of claim 30 further comprising resuming calculating a volume or flow rate of the fuel dispensed to the vehicle based on the meter signal after expiration of the predetermined period of time.

32. The method of claim 29, wherein compensating the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition comprises applying a mathematical factor to the calculated volume or flow rate of the fuel.

33. The method of claim 29, wherein detecting the non-steady state condition is based on detecting a pressure spike by at least one of the first pressure sensor and the second pressure sensor in the fuel flow path.

34. The method of claim 29 further comprising comparing the first pressure signal associated with the pressure sensed by the first pressure sensor with the second pressure signal associated with the pressure sensed by the second pressure sensor and from the comparison determining whether a non-steady state condition exists in the fuel flow path.

35. The method of claim 29 further comprising determining that a local nozzle snap caused the non-steady state condition.

36. The method of claim 29 further comprising determining that a remote nozzle snap caused the non-steady state condition.

37. The method of claim 29, wherein compensating the calculated volume or flow rate of the fuel in response to detection of the non-steady state condition comprises disregarding the meter signal for a predetermined period of time and wherein the predetermined period of time is based on comparing the first pressure signal associated with the pressure sensed by the first pressure sensor with the second pressure signal associated with the pressure sensed by the second pressure sensor.

38. The method of claim 29, wherein the non-steady state condition comprises a reversal of the fuel flow in the fuel flow path.

39. The method of claim 29 further comprising:

receiving a third pressure signal from a third pressure sensor positioned in the fuel flow path upstream from the meter; and

calculating a volume or flow rate of the fuel delivered to the vehicle based on the meter signal, the first pressure signal, and at least one of the second pressure signal and the third pressure signal.