Oxygen monitoring and apparatus
First Claim
1. Oxygen monitoring apparatus, comprising:
- a flow component including;
a flow passage; and
a luminescable composition positioned so as to be exposed to gases flowing through said flow passage, luminescence of said luminescable composition being quenched when said luminescable composition is exposed to oxygen; and
a transducer removably securable to said flow component and including;
a radiation source which emits at least a wavelength of electromagnetic radiation capable of exciting said luminescable composition; and
a detector configured to sense electromagnetic radiation of at least one wavelength emitted by said luminescable composition and to produce a signal indicative of an intensity of said at least one wavelength emitted by said luminescable composition, said detector being oriented, upon securing said transducer to said flow component, to receive electromagnetic radiation emitted by said luminescable composition.
7 Assignments
0 Petitions
Accused Products
Abstract
Apparatus or systems which employ luminescence quenching to produce an oxygen concentration indicative signal. Components of such systems include: (1) an airway adapter, sampling cell, or the like having a sensor which is excited into luminescence with the luminescence decaying in a manner reflecting the concentration of oxygen in gases flowing through the airway adapter or other flow device; (2) a transducer which has a light source for exciting a luminescable composition in the sensor into luminescence and a light sensitive detector for converting energy emitted from the luminescing composition as that composition is quenched into an electrical signal indicative of oxygen concentration in the gases being monitored; and (3) subsystems for maintaining the sensor temperature constant and for processing the signal generated by the light sensitive detector. Sensors for systems of the character just described, methods of fabricating those sensors, and methods for installing the sensors in the flow device.
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Citations
77 Claims
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1. Oxygen monitoring apparatus, comprising:
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a flow component including;
a flow passage; and
a luminescable composition positioned so as to be exposed to gases flowing through said flow passage, luminescence of said luminescable composition being quenched when said luminescable composition is exposed to oxygen; and
a transducer removably securable to said flow component and including;
a radiation source which emits at least a wavelength of electromagnetic radiation capable of exciting said luminescable composition; and
a detector configured to sense electromagnetic radiation of at least one wavelength emitted by said luminescable composition and to produce a signal indicative of an intensity of said at least one wavelength emitted by said luminescable composition, said detector being oriented, upon securing said transducer to said flow component, to receive electromagnetic radiation emitted by said luminescable composition. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77)
a reference detector; and
a beam splitter for dividing the light propagated from said radiation source between said data detector and said reference detector.
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5. Oxygen monitoring apparatus as defined in claim 1 in which said luminescable composition is embedded in a porous polymer.
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6. Oxygen concentration monitoring apparatus as defined in claim 1 wherein at least one window in said flow component facilitates the transmission of electromagnetic radiation from said radiation source to said luminescable composition and from said luminescable composition to said detector.
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7. Oxygen monitoring apparatus as defined in claim 1 in which said detector comprises a photodiode.
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8. Oxygen monitoring apparatus as defined in claim 1, further comprising a filter adjacent said radiation source to prevent exposure of said luminescable composition to radiation of at least some wavelengths of electromagnetic radiation emitted from said radiation source.
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9. Oxygen monitoring apparatus as defined in claim 1 in which said transducer comprises at least one platform for supporting said radiation source and said detector.
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10. Oxygen monitoring apparatus as defined in claim 1 in which said luminescable composition comprises a phosphorescent organometallic complex.
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11. Oxygen monitoring apparatus as defined in claim 1, further comprising a temperature sensor configured to sense a temperature of at least one of said heater component, said thermal capacitor, and said luminescable composition.
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12. Oxygen monitoring apparatus as defined in claim 1 in which said luminescable composition is positioned within said flow passage.
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13. Oxygen monitoring apparatus as defined in claim 1 in which said signal indicative of said intensity of said at least one wavelength emitted by said luminescable composition is also indicative of a concentration of oxygen in respiratory gas to which said luminescable composition is exposed.
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14. Oxygen monitoring apparatus as defined in claim 1 in which said radiation source emits electomagnetic radiation of at least wavelengths from about 300 nm to about 600 nm.
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15. Oxygen monitoring apparatus as defined in claim 1 in which said luminescable composition absorbs electromagnetic radiation of at least wavelengths from about 400 nm to about 700 nm.
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16. Oxygen monitoring apparatus as defined in claim 1 in which said luminescable composition emits electromagnetic radiation of at least wavelengths from about 500 nm to about 1,100 nm.
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17. Oxygen monitoring apparatus as defined in claim 1 in which said radiation source is configured to emit said electromagnetic radiation in a pulsed manner.
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18. Oxygen monitoring apparatus as defined in claim 1 in which said radiation source is oriented, upon securing said transducer to said flow component, to emit said electromagnetic radiation toward said luminescable composition.
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19. Oxygen monitoring apparatus as defined in claim 1, wherein said at least one wavelength of electromagnetic radiation emitted by said luminescable composition and sensed by said detector is in the visible light range.
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20. Oxygen monitoring apparatus as defined in claim 19, further comprising a filtering element configured to prevent said detector from receiving wavelengths of electromagnetic radiation emitted from said luminescable composition that do not indicate an amount of oxygen to which said luminescable composition has been exposed.
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21. Oxygen monitoring apparatus as defined in claim 1 which comprises a second radiation source which emits at least a calibration wavelength of electromagnetic radiation.
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22. Oxygen monitoring apparatus as defined in claim 21 in which said second radiation source comprises a light-emitting diode.
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23. Oxygen monitoring apparatus as defined in claim 21 in which said detector, upon sensing at least said calibration wavelength, generates a calibration signal.
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24. Oxygen monitoring apparatus as defined in claim 23 in which at least one of said transducer and said flow component includes a resiliently displaceable member which is configured to be displaced upon assembly of said transducer with said flow component so as to expose said first member of said temperature control component and said second member of said temperature control component to one another.
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25. Oxygen monitoring apparatus as defined in claim 21 in which said electromagnetic radiation emitted from said second radiation source does not substantially cause said luminescable composition to luminesce.
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26. Oxygen monitoring apparatus as defined in claim 21 in which said second radiation source emits at least an orange, red, or infrared wavelength of electromagnetic radiation.
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27. Oxygen monitoring apparatus as defined in claim 1 in which said transducer includes a center section and first and second end sections on opposite sides of said center section which cooperate to define a well configured to receive a portion of said flow component.
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28. Oxygen monitoring apparatus as defined in claim 27 in which said radiation source is positioned at least partially in said first member of said transducer and said detector is positioned at least partially in said second member of said transducer.
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29. Oxygen monitoring apparatus as defined in claim 1 in which said radiaton source comprises a light-emitting diode.
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30. Oxygen monitoring apparatus as defined in claim 29 in which said radiation source emits at least a blue or green wavelength of visible light.
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31. Oxygen monitoring apparatus as defined in claim 1 in which said luminescable composition comprises a fluorinated porphyrin.
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32. Oxygen monitoring apparatus as defined in claim 31 in which the luminescable composition comprises at least one of palladium mesotetraphenyl porphine, platinum meso-tetraphenyl porphine, palladium meso-tetra (perfluoro) phenyl porphine, and platinum meso-tetra (perfluoro) porphine.
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33. Oxygen monitoring apparatus as defined in claim 1 in which said detector comprises a photodiode.
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34. Oxygen monitoring apparatus as defined in claim 33 in which said photodiode comprises a PIN silicon photodiode.
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35. Oxygen monitoring apparatus as defined in claim 1 in which said transducer is configured to communicate said signal to a processor.
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36. Oxygen monitoring apparatus as defined in claim 35, wherein said processor is configured to increase a signal-to-noise ratio of said signal.
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37. Oxygen monitoring apparatus as defined in claim 35 in which said processor converts said signal into an oxygen concentration signal.
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38. Oxygen monitoring apparatus as defined in claim 37 in which said processor utilizes a first signal processing protocol if the oxygen concentration in monitored gases is low and utilizes a second signal processing protocol if the oxygen concentration in said monitored gases is high.
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39. Oxygen monitoring apparatus as defined in claim 1 in which a portion of said transducer is configured to removably interconnect with a complementary portion of said flow component.
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40. Oxygen monitoring apparatus as defined in claim 39 in which said portion of said transducer receives said complementary portion of said flow component.
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41. Oxygen monitoring apparatus as defined in claim 39 in which at least one of said flow component and said transducer is configured to prevent improper assembly of said flow component and said transducer.
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42. Oxygen monitoring apparatus as defined in claim 1, further comprising a temperature control component configured to maintain said luminescable composition at a substantially constant temperature.
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43. Oxygen monitoring apparatus as defined in claim 42 in which said temperature control component includes members in both said transducer and said flow component.
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44. Oxygen monitoring apparatus as defined in claim 42 in which said flow component includes at least a portion of said temperature control component.
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45. Oxygen monitoring apparatus as defined in claim 42 in which said transducer comprises at least a portion of said temperature control component.
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46. Oxygen monitoring apparatus as defined in claim 45 in which said filtering element comprises an optical filter positioned in an optical path between said luminescable composition and said detector.
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47. Oxygen monitoring apparatus as defined in claim 42 in which said transducer includes a first member of said temperature control component and said flow component includes a second member of said temperature control component.
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48. Oxygen monitoring apparatus as defined in claim 42 in which said temperature control component includes:
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a heater component carried by said transducer; and
a thermal capacitor carried by said flow component and located proximate to said luminescable composition.
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49. Oxygen monitoring apparatus as defined in claim 48 in which said heater component protrudes through an aperture of said transducer.
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50. Oxygen monitoring apparatus as defined in claim 48 in which said heater component comprises a thermally conductive component and a thick film heater affixed to said thermally conductive component.
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51. Oxygen monitoring apparatus as defined in claim 48 in which said thermal capacitor is in intimate contact with a matrix that carries said luminescable composition.
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52. Oxygen monitoring apparatus as defined in claim 51 in which said thermal capacitor is located within an aperture of the airway adapter and at least edge portions of said matrix are held between said thermal capacitor and a surface of said aperture.
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53. Oxygen monitoring apparatus as defined in claim 48 further comprising a temperature control associated with said heater component.
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54. Oxygen monitoring apparatus as defined in claim 53 in which said temperature control comprises a PID controller.
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55. Oxygen monitoring apparatus as defined in claim 48 in which, upon assembly of said flow component and said transducer, said heater component and said thermal capacitor are biased against one another.
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56. Oxygen monitoring apparatus as defined in claim 55, further comprising a biasing member which, upon assembly of said flow component and said transducer, biases said heater component and said thermal capacitor against one another.
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57. Oxygen monitoring apparatus as defined in claim 56 in which said resilient biasing member is configured to displace said heater component relative to a remainder of said transducer to compensate for misalignments between said heater component and said thermal capacitor.
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58. Oxygen monitoring apparatus as defined in claim 1 in which said luminescable composition communicates with said flow passage by way of a sidestream conduit.
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59. Oxygen monitoring apparatus as defined in claim 58, further comprising a pump in communication with said sidestream conduit, said pump being configured to effect a flow of one or more gases into contact with said luminescable composition.
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60. Oxygen monitoring apparatus as defined in claim 59, further comprising a pump controller for controlling pressure within said sampling cell.
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61. Oxygen monitoring apparatus as defined in claim 60 in which said pump controller operates based on signals from a pressure transducer in communication with said sampling cell.
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62. Oxygen monitoring apparatus as defined in claim 59, further comprising an accumulator in said flow path to dampen the pressure pulses generated by operation of said pump.
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63. Oxygen monitoring apparatus as defined in claim 62, further comprising a flow restrictor in said flow path to further dampen pressure pulses generated by operation of said pump.
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64. Oxygen monitoring apparatus as defined in claim 59 in which said luminescable composition is located within a sampling cell.
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65. Oxygen monitoring apparatus as defined in claim 64 in which said sampling cell is replaceably removable from the system said flow component.
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66. Oxygen monitoring apparatus as defined in claim 64, further comprising a pressure transducer configured to compare the actual pressure in said sampling cell with said baseline pressure.
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67. Oxygen monitoring apparatus as defined in claim 66, further comprising an alarm that is activated if said pressure in said sampling cell varies from said baseline pressure.
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68. Oxygen monitoring apparatus as defined in claim 66 in which said pressure transducer comprises:
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an absolute pressure transducer;
a differential pressure transducer; and
a valve which is selectively operable to provide communication between said flow path and said absolute pressure transducer, said flow path and ambient surroundings, and said flow path and said differential pressure transducer.
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69. Oxygen monitoring apparatus as defined in claim 66, wherein said pressure transducer comprises a differential pressure transducer and further including a flow restrictor in said flow path.
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70. Oxygen monitoring apparatus as defined in claim 64 in which said sampling cell communicates with ambient surroundings to establish atmospheric pressure as a baseline pressure in said sampling cell.
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71. Oxygen monitoring apparatus as defined in claim 1 in which said luminescable composition is carried by a matrix.
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72. Oxygen monitoring apparatus as defined in claim 71 in which said matrix includes pores having sizes of about 0.1 μ
- m to about 10 μ
m.
- m to about 10 μ
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73. Oxygen monitoring apparatus as defined in claim 71 in which said matrix has a thickness of about 5 μ
- m to about 20 μ
m.
- m to about 20 μ
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74. Oxygen monitoring apparatus as defined in claim 71 in which said matrix comprises a polymer.
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75. Oxygen monitoring apparatus as defined in claim 74 in which said polymer comprises at least one of a silicone, a polycarbonate, a polystyrene, a polymethyl methacrylate, a polyvinyl chloride, a polypropylene, a polyester, and an acrylic copolymer.
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76. Oxygen monitoring apparatus as defined in claim 75 in which said polymer is a track etched polycarbonate.
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77. Oxygen monitoring apparatus as defined in claim 74 in which said polymer is a hydrophobic polymer.
Specification