IONIC PROBE

• US 20090101524A1
• Filed: 10/10/2008
• Published: 04/23/2009
• Est. Priority Date: 09/06/2006
• Status: Active Grant

• Current Assignee: Hach Company (Veralto Corp.)
• Original Assignee: Hach Company (Veralto Corp.)
• Inventors: Young, Russell Martin, Woodward, John Robert, Livrozet, Pierre Antoine Robert, Schvan, Jean-Francois Maurice Rene
• Granted Patent: US 8,551,311 B2
• Time in Patent Office: Days
• US Class Current: 205/787.500
• CPC Class Codes: G01N 27/302 pH sensitive, e.g. quinhydron, antimony or hydrogen electrodes ion selective electrodes G01N27/333, glass electrodes G01N27/36
• CPC Class Codes: G01N 27/36 Glass electrodes
• CPC Class Codes: G01N 27/4035 Combination of a single ion-sensing electrode and a single reference electrode G01N27/406 and G01N27/413 take precedence

Abstract

An ionic probe is provided according to the invention. The ionic probe includes an active electrode configured to generate a measurement signal for an external test fluid, a first reference electrode configured to generate a first reference signal, and an at least second reference electrode configured to generate at least a second reference signal. The measurement signal is compared to the first reference signal and the at least second reference signal in order to determine an ionic measurement of the external test fluid.

Claims

1. An ionic probe, comprising:

an active electrode configured to generate a measurement signal for an external test fluid;

a first reference electrode configured to generate a first reference signal; and

an at least second reference electrode configured to generate at least a second reference signal;

wherein the measurement signal is compared to the first reference signal and the at least second reference signal in order to determine an ionic measurement of the external test fluid.

2. The ionic probe of claim 1, with the active electrode being located in an active electrolyte that ionically interacts with the external test fluid, with the first reference electrode being located in a first reference solution that ionically interacts with a middle solution, and with the second reference electrode being located in a second reference solution that ionically interacts with an outer solution, wherein the middle solution and the second reference solution ionically interact with the external test fluid.

3. The ionic probe of claim 1, with the ionic probe further comprising:

an inner shell forming an active chamber and including an active electrolyte solution and an active ion sensitive region that protrudes from the ionic probe and is adapted to contact the external test fluid, with the active ion sensitive region allowing ion interaction between the active electrolyte solution and the external test fluid;

the active electrode located in the active chamber and configured to generate a measurement signal related to an ionic potential between the external test fluid and the active electrolyte solution;

a middle divider located inside the inner shell and forming a first reference chamber, with the first reference chamber holding a first reference solution and including at least one first ion sensitive region formed in the inner shell, with the at least one first ion sensitive region allowing ion interaction between the first reference solution and a middle solution that is external to the inner shell at the first ion sensitive region;

the first reference electrode located within the first reference chamber and configured to generate a first reference signal related to an ionic potential between the first reference solution and the middle solution;

a middle shell forming a second reference chamber and holding a second reference solution and including at least one second ion sensitive region formed in the middle shell, with the at least one second ion sensitive region completing a circuit between the second reference solution and an outer solution that is external to the middle shell at the second ion sensitive region; and

the second reference electrode located in the second reference chamber and configured to generate at least a second reference signal related to an ionic potential between the second reference solution and the outer solution.

4. The ionic probe of claim 3, wherein one or more of the active ion sensitive region, the at least one first ion sensitive region, or the at least one second ion sensitive region comprise patches of ion sensitive material bonded to the inner shell and the middle shell.

5. The ionic probe of claim 1, wherein the first reference signal is compared to the at least second reference signal in order to determine a correction value to be applied to the ionic measurement.

6. The ionic probe of claim 1, wherein the first reference signal is compared to the at least second reference signal in order to detect a single reference drift in one of the first reference signal or the at least second reference signal.

7. The ionic probe of claim 1, wherein the first reference signal and the at least second reference signal are compared to a predetermined reference voltage in order to detect a dual reference drift in both the first reference signal and the at least second reference signal.

8. The ionic probe of claim 1, where the inner shell, the middle divider, and the middle shell are substantially mono-axial/coaxial.

9. The ionic probe of claim 1, further comprising an outer shell holding at least an outer solution, with the outer solution being configured to ionically interact with the second reference solution through the at least second ion sensitive region.

10. The ionic probe of claim 1, further comprising an outer shell, wherein the inner shell, the middle shell, the inner divider, and the outer shell are substantially mono-axial/coaxial.

11. The ionic probe of claim 1, wherein the at least second reference electrode comprises a redundant electrode that can be selectively employed.

12. The ionic probe of claim 1, wherein the at least second reference electrode comprises a redundant electrode unit that can be selectively exposed to the external test fluid.

13. An ionic probe, comprising:

an inner shell forming an active chamber and including an active electrolyte solution and an active ion sensitive region that protrudes from the ionic probe and is adapted to contact an external test fluid, with the active ion sensitive region allowing ion interaction between the active electrolyte solution and the external test fluid;

an active electrode located in the active chamber and configured to generate a measurement signal related to an ionic potential between the external test fluid and the active electrolyte solution;

a middle divider located inside the inner shell and forming a first reference chamber, with the first reference chamber holding a first reference solution and including at least one first ion sensitive region formed in the inner shell, with the at least one first ion sensitive region allowing ion interaction between the first reference solution and a middle solution that is external to the inner shell at the first ion sensitive region;

a first reference electrode located within the first reference chamber and configured to generate a first reference signal related to an ionic potential between the first reference solution and the middle solution;

a middle shell forming a second reference chamber and holding a second reference solution and including at least one second ion sensitive region formed in the middle shell, with the at least one second ion sensitive region allowing ion interaction between the second reference solution and an outer solution that is external to the middle shell at the second ion sensitive region; and

a second reference electrode located in the second reference chamber and configured to generate at least a second reference signal related to an ionic potential between the second reference solution and the outer solution, wherein the measurement signal is compared to the first reference signal and the at least second reference signal in order to determine an ionic measurement of the external test fluid.

14. The ionic probe of claim 13, wherein one or more of the active ion sensitive region, the at least one first ion sensitive region, or the at least one second ion sensitive region comprise patches of ion sensitive material bonded to the inner shell and the middle shell.

15. The ionic probe of claim 13, wherein the first reference signal is compared to the at least second reference signal in order to determine a correction value to be applied to the ionic measurement.

16. The ionic probe of claim 13, wherein the first reference signal is compared to the at least second reference signal in order to detect a single reference drift in one of the first reference signal or the at least second reference signal.

17. The ionic probe of claim 13, wherein the first reference signal and the at least second reference signal are compared to a predetermined reference voltage in order to detect a dual reference drift in both the first reference signal and the at least second reference signal.

18. The ionic probe of claim 13, where the inner shell, the middle shell, and the outer shell are substantially mono-axial/coaxial.

19. The ionic probe of claim 13, further comprising an outer shell holding at least an outer solution, with the outer solution being configured to ionically interact with the second reference solution through the at least second ion sensitive region.

20. The ionic probe of claim 13, further comprising an outer shell, wherein the inner shell, the middle shell, the inner divider, and the outer shell are substantially mono-axial/coaxial.

21. The ionic probe of claim 13, wherein the at least second reference electrode comprises a redundant electrode that can be selectively employed.

22. The ionic probe of claim 13, wherein the at least second reference electrode comprises a redundant electrode unit that can be selectively exposed to the external test fluid.

23. An ionic meter, comprising:

an ionic probe comprising;

an active electrode configured to generate a measurement signal for an external test fluid;

a first reference electrode configured to generate a first reference signal; and

at least a second reference electrode configured to generate an at least second reference signal;

a cable coupled to the ionic probe; and

meter electronics coupled to the cable and configured to receive the measurement signal, the to first reference signal, and the at least second reference signal and compare the measurement signal to the first reference signal and the at least second reference signal in order to determine an ionic measurement of the external test fluid.

24. The ionic meter of claim 23, with the active electrode being located in an active electrolyte that ionically interacts with the external test fluid, with the first reference electrode being located in a first reference solution that ionically interacts with a middle solution, and with the second reference electrode being located in a second reference solution that ionically interacts with an outer solution, wherein the middle solution and the outer solution ionically interact with the external test fluid.

25. The ionic meter of claim 23, with the meter electronics being further configured to compare the first reference signal to the at least second reference signal in order to determine a correction value to be applied to the ionic measurement.

26. The ionic meter of claim 23, with the meter electronics being further configured to compare the first reference signal to the at least second reference signal in order to detect a single reference drift in one of the first reference signal or the at least second reference signal.

27. The ionic meter of claim 23, with the meter electronics being further configured compare the first reference signal and the at least second reference signal to a predetermined reference voltage in order to detect a dual reference drift in both the first reference signal and the at least second reference signal.

28. The ionic meter of claim 23, with the ionic probe further comprising:

an inner shell forming an active chamber and including an active electrolyte solution and an active ion sensitive region that protrudes from the ionic probe and is adapted to contact an external test fluid, with the active ion sensitive region allowing ion interaction between the active electrolyte solution and the external test fluid;

an active electrode located in the active chamber and configured to generate a measurement signal related to an ionic potential between the external test fluid and the active electrolyte solution;

a middle divider located inside the inner shell and forming a first reference chamber, with the first reference chamber holding a first reference solution and including at least one first ion sensitive region formed in the inner shell, with the at least one first ion sensitive region allowing ion interaction between the first reference solution and a middle solution that is external to the inner shell at the first ion sensitive region;

a first reference electrode located within the first reference chamber and configured to generate a first reference signal related to an ionic potential between the first reference solution and the middle solution;

a middle shell forming a second reference chamber and holding a second reference solution and including at least one second ion sensitive region formed in the middle shell, with the at least one second ion sensitive region completing a circuit between the second reference solution and an outer solution that is external to the middle shell at the second ion sensitive region; and

a second reference electrode located in the second reference chamber and configured to generate at least a second reference signal related to an ionic potential between the second reference solution and the outer solution.

29. The meter of claim 28, where the inner shell, the middle shell, and the outer shell are substantially mono-axial/coaxial.

30. The meter of claim 23, further comprising an outer shell holding at least an outer solution, with the outer solution being configured to ionically interact with the second reference solution through the at least second ion sensitive region.

31. The meter of claim 23, further comprising an outer shell, wherein the inner shell, the middle shell, the inner divider, and the outer shell are substantially mono-axial/coaxial.

32. The meter of claim 23, wherein the at least second reference electrode comprises a redundant electrode that can be selectively employed.

33. The meter of claim 23, wherein the at least second reference electrode comprises a redundant electrode unit that can be selectively exposed to the external test fluid.

34. A self-correction method for an ionic meter, comprising:

generating a measurement signal;

generating a first reference signal;

generating at least a second reference signal; and

comparing the measurement signal to the first reference signal and the at least second reference signal in order to determine an ionic measurement of an external test fluid.

35. The method of claim 34, further comprising comparing the first reference signal to the at least second reference signal in order to determine a correction value to be applied to the ionic measurement.

36. The method of claim 34, further comprising comparing the first reference signal to the at least second reference signal in order to detect a single reference drift in one of the first reference signal or the at least second reference signal.

37. The method of claim 34, further comprising comparing the first reference signal and the at least second reference signal to a predetermined reference voltage in order to detect a dual reference drift in both the first reference signal and the at least second reference signal.

38. The method of claim 34, wherein the first reference signal is generated with respect to a first reference solution and the at least second reference signal is generated with respect to an at least second reference solution.

39. The method of claim 34, wherein the first reference signal is generated with respect to a first reference solution including a predetermined first pH level and the at least second reference signal is generated with respect to an at least second reference solution including a predetermined second pH level that is different from the predetermined first pH level.