Linear position indicator system and method

• US 7,343,800 B2
• Filed: 09/22/2006
• Issued: 03/18/2008
• Est. Priority Date: 09/23/2005
• Status: Expired due to Fees

• Current Assignee: PCS Ferguson Incorporated (ChampionX Corporation)
• Original Assignee: FB Imonitoring, Inc.
• Inventors: Dixon, David M., Harman, Robert M., Barry, Alexander M., Couch, Philip R.
• Primary Examiner(s): Larkin; Daniel S.
• Assistant Examiner(s): West; Paul M
• Application Number:
  US11/525,501
• Publication Number:
  US 20070186648A1
• Time in Patent Office: 543 Days
• Field of Search: 733/19, 733/13, 733/225
• US Class Current: 73/319
• CPC Class Codes: G01F 23/68 using electrically actuated indicating means
• CPC Class Codes: G01F 23/72 using magnetically actuated indicating means

Abstract

The present invention is directed to system and method for determining a fluid level. The system comprises a sensing rod assembly comprised of releasably connectable rod segments. Each rod segment carries a processor and a plurality of inductors. Each inductor generates a position signal responsive to a float signal. A float assembly comprises a housing containing a circuit having an integrally formed coil periodically energizable by a processor to emit the float signal. A control assembly receives the generated position signals and determines the fluid level. The method comprises providing releasably connectable rod segments with inductors that generate a position signal responsive to a float signal, determining a sensing rod assembly length, forming the sensing rod assembly, disposing it within a container, providing a float assembly periodically actuated to generate a float signal, generating position signals responsive to the float signal and analyzing those signals to determine the fluid level.

Claims

1. A linear position indicator system for determining the first fluid level of a first fluid within a container and having a first fluid surface, comprising:

a sensing rod assembly extending substantially vertically within said container, said sensing rod assembly comprising a sensing rod having a plurality of releasably connectable rod segments, each said rod segment extending a given segment length and carrying a rod controller and a plurality of inductors spaced apart given distances along said segment length, each said inductor being responsive to a first float signal to generate one or more first position signals;

a first float assembly capable of floating at said first fluid surface and vertically movable along said sensing rod assembly, comprising

(i) a coil energizable to emit said first float signal,

(ii) a control circuit configured to periodically energize said coil;

(iii) a power supply electrically associated with said control circuit;

(iv) a fluid-resistant housing containing said coil, said control circuit, and said power supply;

a control assembly electrically associated with said sensing rod assembly and including a controller responsive to receive said first position signals generated by each said inductor and to determine from said first position signals said first fluid level of said first fluid in said container.

2. The linear position indicator system of claim 1 wherein said given length of each said rod segment is about 12 inches.

3. The linear position indicator system of claim 1 wherein said given length of each said rod segment is about 19 inches.

4. The linear position indicator system of claim 1 wherein each said rod segment comprises a printed circuit board with one surface extending between a first end and a second end, said first end bearing a first connector component and said second end bearing a second connector component.

5. The linear position indicator system of claim 4 wherein said first connector component comprises a male connector component having a plurality of connector pins extending perpendicularly to said one surface and said second connector component comprises a female connector component having a plurality of apertures corresponding to said connector pins.

6. The linear position indicator system of claim 1, wherein said plurality of inductors comprise radio frequency identification transducer coils.

7. The linear position indicator system of claim 4, wherein said plurality of inductors comprise radio frequency identification transducer coils.

8. The linear position indicator system of claim 4, wherein said plurality of inductors comprise a plurality of coils integrally formed on said printed circuit board.

9. The linear position indicator system of claim 4, further comprising a potting compound encasing said printed circuit board.

10. The linear position indicator system of claim 1, further comprising:

a sensing rod housing surmounting said sensing rod assembly and having a plurality of releasably connected housing segments.

11. The linear position indicator system of claim 9, wherein said sensing rod housing segments comprise fiberglass tubes extending a given length between a first end and a second end, said first and second ends bearing threads for releasably connecting said fiberglass tubes together.

12. The linear position indicator system of claim 1, wherein each said rod segment rod controller comprises a microprocessor.

13. The linear position indicator system of claim 1, wherein said first float assembly control circuit comprises a microprocessor.

14. The linear position indicator system of claim 1, wherein said control assembly controller comprises a microprocessor.

15. The linear position indicator system of claim 1, wherein said fluid-resistant housing comprises a potting compound.

16. The linear position indicator system of claim 1, wherein said container contains a second fluid having a second fluid surface, further comprising:

each said inductor of said sensing rod being responsive to a second float signal to generate a second position signal;

a second float assembly capable of floating on said second fluid surface and vertically movable along said sensing rod assembly, comprising

(i) a circuit having an integrally formed coil energizable to emit said second float signal,

(ii) a processor programmed to periodically energize said coil;

(iii) a power supply electrically associated with said processor;

(iv) a fluid-resistant housing containing said circuit, said processor, and said power supply;

said processor of said control assembly being programmed to receive said second position signal generated by each said inductor and to determine from said second position signals said second fluid level of said second fluid in said container.

17. The linear position indicator system of claim 15, wherein said container comprises a tank and said first fluid comprises oil and said second fluid comprises water.

18. The linear position indicator system of claim 1 further comprising a wireless assembly for transmitting generated data from said control assembly to a remote location.

20. The method of claim 18, wherein said container contains a second fluid having a second fluid surface, further comprising the steps of:

(j) providing a second float assembly that floats on said second fluid surface and is vertically movable along said sensing rod assembly, said second float assembly comprising a circuit having an integrally formed coil actuable to generate a second float signal corresponding to the position of said second float assembly;

(g) periodically actuating said second float assembly coil to generate said second float signal;

(h) sensing said second float signal with said inductors to generate a plurality of second position signals; and

(i) analyzing said sensed second position signals to determine said second fluid level of said fluid in said container.

21. The method of claim 18, wherein said step (i) of analyzing said sensed position signals comprises performing a non-linear regression analysis.

19. A method for determining the fluid level of a fluid contained within a container and having a fluid surface, comprising the steps of:

(a) providing a plurality of releasably connectable rod segments, each rod segment extending a given rod segment length and having a plurality of inductors located along said length, each said inductor being responsive to a float signal to generate a position signal;

(d) determining a sensing rod assembly length based on the depth of said container;

(e) forming a sensing rod assembly having said rod assembly length by connecting a plurality of rod segments;

(f) disposing said sensing rod assembly generally vertically within said container;

(g) providing a float assembly that floats at said fluid surface and is vertically movable along said sensing rod assembly, said float assembly comprising a circuit having a coil excitable to generate a float signal corresponding to the position of said float assembly;

(g) periodically exciting said float assembly coil to generate said float signal;

(h) sensing said float signal with said inductors to generate a plurality of position signals; and

(i) analyzing said sensed position signals to determine said fluid level of said fluid in said container.