Thermal and conductivity sensing systems, devices and methods

• US 20070253463A1
• Filed: 04/13/2007
• Published: 11/01/2007
• Est. Priority Date: 04/14/2006
• Status: Active Grant

• Current Assignee: Deka Products Limited Partnership
• Original Assignee: Deka Products Limited Partnership
• Inventors: Tracey, Brian, Perry, N., Demers, Jason
• Granted Patent: US 7,794,141 B2
• Time in Patent Office: Days
• US Class Current: 374/208
• CPC Class Codes: A61F 2007/126 for invasive application, e.g. for introducing into blood vessels
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1605 Physical characteristics of the dialysate fluid
• CPC Class Codes: A61M 1/1656 Apparatus for preparing dialysates
• CPC Class Codes: A61M 1/287 Dialysates therefor
• CPC Class Codes: A61M 1/362227 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/36225 with blood pumping means or components thereof
• CPC Class Codes: A61M 1/362263 Details of incorporated filters
• CPC Class Codes: A61M 1/362265 Details of valves
• CPC Class Codes: A61M 1/3626 Gas bubble detectors
• CPC Class Codes: A61M 1/369 Temperature treatment
• CPC Class Codes: A61M 2205/12 with interchangeable cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 2205/127 with provisions for heating or cooling
• CPC Class Codes: A61M 2205/128 with incorporated valves
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3324 PH measuring means
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 2205/3606 cooled
• CPC Class Codes: A61M 2205/3653 by Joule effect, i.e. electric resistance
• CPC Class Codes: A61M 2205/502 : User interfaces, e.g. screens or keyboards
• CPC Class Codes: A61M 60/113 : in other functional devices, e.g. dialysers or heart-lung machines
• CPC Class Codes: A61M 60/36 : for specific blood treatment; for specific therapy
• CPC Class Codes: A61M 60/43 : using vacuum at the blood pump, e.g. to accelerate filling
• CPC Class Codes: A61M 60/554 : of blood pressure
• CPC Class Codes: A61M 60/837 : Aspects of flexible displacement members, e.g. shapes or materials
• CPC Class Codes: A61M 60/847 : arranged in a cassette
• CPC Class Codes: A61M 60/849 : Disposable parts
• CPC Class Codes: A61M 60/851 : Valves
• CPC Class Codes: A61M 60/892 : Active valves, i.e. actuated by an external force
• CPC Class Codes: A61M 60/894 : Passive valves, i.e. valves actuated by the blood
• CPC Class Codes: F04B 23/06 : the pumps being all of reciprocating positive-displacement type
• CPC Class Codes: F04B 39/12 : Casings; Cylinders; Cylinder heads; Fluid connections
• CPC Class Codes: F04B 39/123 : Fluid connections
• CPC Class Codes: F04B 39/14 : Provisions for readily assembling or disassembling
• CPC Class Codes: F04B 43/0081 : systems, control, safety measures
• CPC Class Codes: F04B 43/073 : the actuating fluid being controlled by at least one valve
• CPC Class Codes: F04B 43/0736 : with two or more pumping chambers in parallel
• CPC Class Codes: F04B 53/16 : Casings; Cylinders; Cylinder liners or heads; Fluid connections
• CPC Class Codes: F04B 53/22 : Arrangements for enabling ready assembly or disassembly
• CPC Class Codes: F04B 7/02 : the valving being fluid-actuated
• CPC Class Codes: G01K 1/08 : Protective devices, e.g. casings
• CPC Class Codes: G01K 1/16 : Special arrangements for conducting heat from the object to the sensitive element
• CPC Class Codes: G01M 3/188 : for radiators
• CPC Class Codes: G05D 7/0682 : using a plurality of flow sources
• CPC Class Codes: Y02A 90/10 : Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Abstract

A sensing probe is described. The sensing probe includes a probe housing having a probe tip. A thermal sensor in the housing is also included. The thermal sensor has a sensing end and a connector end, where the sensing end is thermally coupled to the probe tip. Also included are at least two leads. The leads transfer electrical signals that are used to determine temperature and conductivity. Also included is a thermal well. The thermal well includes a hollow housing of a thermally conductive material. The housing has an outer surface and an inner surface. The inner surface is a predetermined shape so as to form a mating relationship with a sensing probe. The mating thermally couples the inner surface with a sensing probe. In some embodiments, the thermal well is located on a disposable portion and the sensing probe on a reusable portion.

Claims

1. A sensing probe comprising:

a probe housing;

a thermal sensor in said probe housing having a sensing end and a connector end;

a probe tip thermally coupled to said sensing end of the thermal sensor and attached to said probe housing, the probe tip adapted for thermal coupling with an inner surface of a thermal well; and

at least two leads connected to said connector end of said thermal sensor, whereby thermal energy is transferred from said thermal well to said thermal sensor and whereby temperature information is conveyed through said leads.

2. A sensing probe according to claim 1, further comprising a third lead attached to one of the probe housing, the thermal sensor, and the probe tip for permitting conductivity sensing.

3. A sensing probe according claim 1, further comprising urethane resin between said probe tip and said probe housing.

5. A sensing probe according to any of claims 1-4, further comprising thermal epoxy between said thermal sensor and said probe tip.

6. A sensing probe according to any of claims 1-4, where said probe tip is copper.

7. A sensing probe according to any of claims 1-4, wherein said probe tip is steel.

8. A sensing probe according to any of claims 1-4, wherein the probe tip is a metal including at least one of silver, copper, steel, and stainless steel.

9. A sensing probe according to any of claims 1-4, where said probe housing is plastic.

10. A sensing probe according to any of claims 1-4, wherein said probe housing is metal.

11. A sensing probe according to any of claims 1-4, wherein said housing further comprises a flange disposed about said probe housing.

12. A sensing probe according to claim 11, further comprising a spring in communication with the flange.

13. A sensing probe according to claim 1, wherein the probe tip includes a flange for mating with the housing.

14. A sensing probe according to claim 1, further comprising:

a conductivity sensor attached to one of the probe housing, the thermal sensor, and the probe tip for permitting conductivity sensing; and

a third lead attached to the conductivity sensor for transmitting conductivity information.

16. A sensing probe according to any of claims 1-4, wherein the housing includes an integrated flexible member.

48. A sensing system comprising:

a sensing probe as in any of claims 1-16; and

a well as in any of claims 23-43, the well in communication with the sensing probe for at least one of thermal sensing and conductivity sensing.

4. A sensing probe comprising:

a probe housing having a probe tip adapted for thermal coupling with an inner surface of a thermal well;

a thermal sensor in said housing having a sensing end and a connector end, said sensing end thermally coupled to said probe tip; and

at least three leads, wherein said leads transfer electrical signals and whereby said signals are used to determine temperature and conductivity.

15. A sensing probe according to claim 4, further comprising a conductivity sensor attached to the housing, wherein at least one of the leads is attached to the conductivity sensor for transmitting conductivity information.

17. A sensor apparatus comprising:

a probe housing having a probe tip;

a thermal sensor in said housing having a sensing end and a connector end, said sensing end thermally coupled to said probe tip; and

at least three leads, wherein said leads transfer electrical signals and whereby said signals are used to determine a temperature and conductivity.

18. The sensor apparatus of claim 17 further comprising a thermal well of a predetermined size and shape wherein said thermal well mates with said probe and said probe tip is thermal coupled to said thermal well.

19. A thermal well comprising:

a hollow housing of a thermally conductive material, said housing having an outer surface and an inner surface, said inner surface of a predetermined shape so as to form a mating relationship with a sensing probe, whereby said mating thermally couples the inner surface with a sensing probe.

20. The thermal well of claim 19 further comprising a predetermined volume of thermal grease on said inner surface.

21. A method for determining temperature and conductivity of a subject media, said method comprising the steps of:

thermally coupling a thermal well and a sensing probe such that temperature and conductivity can be determined;

transferring thermal and conductivity signals through at least 3 leads from said sensing probe; and

determining temperature and conductivity using said signals.

22. A method for detecting air in a fluid line, said method comprising:

thermally coupling at least two thermal wells located in a fluid line to sensing probes such that temperature and conductivity can be determined;

transferring conductivity signals through at least 3 leads from said sensing probes;

determining conductivity for each sensing probe;

calculating the difference of conductivity from each sensing probe; and

determining if said difference exceeds a threshold.

23. Apparatus comprising a fluid conduit including a well for at least one of transmitting temperature and permitting conductivity sensing of fluid passing through the conduit, wherein the well is adapted for interconnection with a sensor.

24. Apparatus according to claim 23, configured so that a portion of the well comes into contact with fluid in the conduit.

25. Apparatus according to claim 23, configured so that no portion of the well comes into contact with fluid in the conduit.

26. Apparatus according to claim 23, wherein the fluid conduit comprises plastic tubing.

27. Apparatus according to claim 23, wherein the fluid conduit comprises metal tubing.

28. Apparatus according to claim 23, wherein the well and the conduit are integrally formed from the same material.

29. Apparatus according to claim 23, wherein the well is coupled to the fluid conduit.

30. Apparatus according to claim 29, wherein the well is coupled to the fluid conduit using at least one of press fit connection, flexible tabs, adhesive, ultrasonic weld, and a retaining plate and fastener.

31. Apparatus according to claim 29, further including an o-ring between the well and the fluid conduit.

32. Apparatus according to claim 30, wherein the o-ring includes one of a round cross-section, a square cross-section, and an X-shaped cross-section.

33. Apparatus according to claim 31, wherein the well includes a groove to receive a portion of the o-ring.

34. Apparatus according to claim 29, wherein a portion of the well in contact with the conduit is flexible so as to deform the conduit.

35. Apparatus according to claim 34, wherein the portion of the well in contact with the conduit includes a plurality of cuts to provide such flexibility.

36. Apparatus according to claim 23, wherein the well is embedded in the fluid conduit.

37. Apparatus according to claim 36, wherein the well is insert molded into the fluid conduit.

38. Apparatus according to claim 23, wherein the well and the conduit are made of different materials.

39. Apparatus according to claim 38, wherein the conduit is plastic and the well is metallic.

40. Apparatus according to claim 29, wherein the well includes protrusions to help secure the well to the conduit.

41. Apparatus according to claim 23, wherein the conduit has an inner surface and an outer surface and wherein a sensor end of the well is flush with the outer surface.

42. Apparatus according to claim 23, wherein the conduit has an inner surface and an outer surface and wherein a sensor end of the well protrudes beyond the outer surface.

43. Apparatus according to claim 23, wherein the conduit has an inner surface and an outer surface and wherein a sensor end of the well is recessed from the outer surface.

44. A fluid pumping apparatus comprising at least one pump and a well for at least one of transmitting temperature and permitting conductivity sensing of fluid passing through the conduit, wherein the well is adapted for interconnection with a sensor.

45. A fluid pumping apparatus according to claim 44, wherein the at least one pump includes at least one pod pump.

46. A fluid pumping apparatus according to claim 45, wherein the at least one pod pump comprises a pair of pod pumps.

47. A fluid pumping apparatus according to claim 44, wherein the at least one pump and the well are integrated into a cassette.