METHODS AND APPARATUS TO DETERMINE A POSITION OF A VALVE

• US 20080308157A1
• Filed: 04/07/2008
• Published: 12/18/2008
• Est. Priority Date: 06/15/2007
• Status: Active Grant

• Current Assignee: Fisher Controls International LLC (Emerson Electric Company)
• Original Assignee: Fisher Controls International LLC (Emerson Electric Company)
• Inventors: Jun, Fan Jian, Cang, Lu, Zhuang, Yin
• Granted Patent: US 8,387,657 B2
• Time in Patent Office: Days
• US Class Current: 137/12
• CPC Class Codes: F16K 37/0066 Hydraulic or pneumatic means F16K37/0075 takes precedence
• CPC Class Codes: Y10T 137/0379 By fluid pressure
• CPC Class Codes: Y10T 137/8225 Position or extent of motion indicator
• CPC Class Codes: Y10T 137/8326 Fluid pressure responsive indicator, recorder or alarm
• CPC Class Codes: Y10T 137/86485 Line condition change responsive release of valve
• CPC Class Codes: Y10T 137/86944 One valve seats against other valve [e.g., concentric valves]

Abstract

Methods and apparatus to indicate a position of a valve are described. An example apparatus includes a first pressure sensor to detect an inlet pressure of a valve, a second pressure sensor to detect an outlet pressure of the valve, and a controller operatively coupled to the first pressure sensor and the second pressure sensor to determine a position of the valve corresponding to one of a plurality of predetermined operational states of the valve.

Claims

1. An apparatus for use with a valve comprising:

a first pressure sensor to detect an inlet pressure of the valve;

a second pressure sensor to detect an outlet pressure of the valve; and

a controller operatively coupled to the first pressure sensor and the second pressure sensor to determine a position of the valve corresponding to one of a plurality of predetermined operational states of the valve.

2. An apparatus as defined in claim 1, wherein the controller calculates a differential pressure between the inlet pressure of the valve and the outlet pressure of the valve to determine the position of the valve.

3. An apparatus as defined in claim 2, wherein the controller is to compare the differential pressure to a predetermined valve pressure value.

4. An apparatus as defined in claim 1, wherein the position indicates whether the valve is prepared to receive an input.

5. An apparatus as defined in claim 1, wherein the one of the plurality of predetermined operational states of the valve comprises an open state, a closed state, or a bleed state.

6. An apparatus as defined in claim 1, further comprising a display operatively coupled to the controller.

7. An apparatus as defined in claim 1, wherein the controller is to communicate a message associated with the position of the valve to a user.

8. An apparatus as defined in claim 1, wherein the valve comprises an internal valve configured to be installed in a tank.

9. An apparatus as defined in claim 8, wherein the inlet pressure is substantially equal to a pressure in the tank.

10. An apparatus as defined in claim 1, wherein the valve is to receive liquefied petroleum gas.

11. An apparatus as defined in claim 1, wherein the valve comprises an internal excess flow valve.

12. A method for use in a valve apparatus, comprising:

obtaining an inlet pressure of the valve;

obtaining an outlet pressure of the valve; and

comparing the inlet pressure to the outlet pressure to determine a position of the valve corresponding to one of a plurality of predetermined operational states of the valve.

13. A method as defined in claim 12, wherein comparing the inlet pressure to the outlet pressure comprises calculating a differential pressure between the inlet pressure and the outlet pressure of the valve.

14. A method as defined in claim 13, further comprising comparing the differential pressure to a predetermined valve pressure value to determine the position of the valve.

15. A method as defined in claim 12, wherein the position of the valve indicates whether the valve is prepared to receive an input.

16. A method as defined in claim 12, wherein the one of the plurality of predetermined operational states of the valve comprises an open state, a closed state, or an intermediate state.

17. A method as defined in claim 12, further comprising communicating a message to a user associated with the plurality of predetermined operational states of the valve.

20. A method as defined in claim 12, wherein the plurality of predetermined operational states of the internal valve comprises an open state, a closed state, or a bleed state.

18. A system comprising:

a tank having an internal valve to control a flow of fluid;

a first pressure sensor to detect an inlet pressure of the internal valve;

a second pressure sensor to detect an outlet pressure of the internal valve;

a controller operatively coupled to the first pressure sensor and the second pressure sensor, wherein the controller is to calculate a differential pressure between the inlet pressure and the outlet pressure, and wherein the differential pressure indicates a position of the internal valve corresponding to one of a plurality of predetermined operational states of the internal valve; and

a display operatively coupled to the controller to communicate the position of the internal valve to a user.

19. A system as defined in claim 18, wherein the inlet pressure is substantially equal to a pressure of the tank.

21. A system as defined in claim 18, wherein the position indicates whether the valve is prepared to receive an input from the user.