US6128910A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diagnostic unit for an air conditioning system
Assignee: ENALASYS Corp
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Filing: 1997-08-19
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Granted: 2000-10-10
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Expires: 2017-08-19
Abstract
Abstract An apparatus and method for noninvasively diagnosing a closed air refrigeration system includes a sensing unit which can be selectively placed over the evaporator inlet duct and the evaporator outlet duct to respectively measure the evaporator inlet enthalpy and the evaporator outlet enthalpy. Using both of these enthalpies, a computer calculates a sensible heat ratio for the evaporator which is useable to diagnose the system. Similarly, the sensing unit can be selectively placed over the condenser intake and condenser exhaust to measure the condenser intake enthalpy and the condenser exhaust enthalpy. Using these enthalpies, the computer calculates a sensible heat ratio for the condenser which is useable to further diagnose the system. Further, superheat and subcool set points can be calculated and compared with rated set points to evaluate the system. In an alternate embodiment, separate sensing units can be used simultaneously to measure the various enthalpies.
Inventors
- 👤 John E. Faircloth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 05:26
CPC Classifications
F; F25; F25B; F25B49/00; F25B49/005; F24; F24F; F24F11/00; F24F11/30; F24F11/32; F24F11/38
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
122 words
An apparatus for noninvasively diagnosing a closed air refrigeration system, the system having an evaporator with an inlet and an outlet and a condenser with an intake and an exhaust, the apparatus comprising: a sensor means for measuring enthalpy components, wherein said enthalpy components include dry bulb temperature and relative humidity; a computer means electrically connected with said sensor means for calculating an inlet enthalpy from the measured components when said sensor means is placed near said evaporator inlet, and calculating an outlet enthalpy from the measured components when said sensor is placed near said evaporator outlet, and comparing said inlet enthalpy with said outlet enthalpy to determine a total heat transfer (Q TOT ) for use in diagnosing said refrigeration system.
Claim 2
Independent Claim
122 words
An apparatus for noninvasively diagnosing a closed air refrigeration system, the system having an evaporator with an inlet and an outlet and a condenser with an intake and an exhaust, the apparatus comprising: a sensor means for measuring enthalpy components, wherein said enthalpy components include dry bulb temperature and relative humidity; a computer means electrically connected with said sensor means for calculating an inlet enthalpy from the measured components when said sensor means is placed near said evaporator inlet, and calculating an outlet enthalpy from the measured components when said sensor is placed near said evaporator outlet, and comparing said inlet enthalpy with said outlet enthalpy to determine a total heat transfer (Q TOT ) for use in diagnosing said refrigeration system.
Claim 3
Dependent Claim
63 words
An apparatus as recited in claim 1 wherein said computer means calculates an intake enthalpy from the measured components when said sensor is placed near said condenser intake and an exhaust enthalpy from the measured components when said sensor is placed near said condenser exhaust and wherein said computer means compares said intake enthalpy with said exhaust enthalpy for diagnosing said refrigeration system.
Claim 4
Dependent Claim
28 words
An apparatus as recited in claim 2 wherein said sensor means is selectively positionable near said evaporator inlet, said evaporator outlet, said condenser intake, and said condenser exhaust.
Claim 5
Dependent Claim
77 words
An apparatus as recited in claim 2 wherein said sensor means comprises: an inlet sensing unit positioned near the evaporator inlet for measuring said evaporator inlet enthalpy components; an outlet sensing unit positioned near the evaporator outlet for measuring said evaporator outlet enthalpy components; an intake sensing unit positioned near the condenser intake for measuring a condenser intake enthalpy components; and an exhaust sensing unit positioned near the condenser exhaust for measuring a condenser exhaust enthalpy components.
Claim 6
Dependent Claim
20 words
An apparatus as recited in claim 1 wherein said computer means compares said inlet enthalpy with said outlet enthalpy simultaneously.
Claim 7
Dependent Claim
39 words
An apparatus as recited in claim 1 wherein said apparatus further includes an instrument means for measuring barometric pressure, and said computing means is connected to said instrument means for using said barometric pressure measurement to calculate said enthalpies.
Claim 8
Dependent Claim
21 words
An apparatus as recited in claim 1 wherein said computer means uses respective said enthalpies to calculate a sensible heat ratio.
Claim 9
Independent Claim
100 words
An apparatus for non-invasively diagnosing a closed air refrigeration system, the system having an evaporator with an inlet and an outlet and a condenser with an intake and an exhaust, the apparatus comprising: a sensing unit selectively positioned near the evaporator inlet for measuring an inlet enthalpy at the evaporator inlet, and near the evaporator outlet for measuring an outlet enthalpy at the evaporator outlet; and a computer means in communication with said sensing unit to compare said inlet enthalpy with said outlet enthalpy to determine a total heat transfer (Q TOT ) for use in diagnosing said refrigeration system.
Claim 10
Independent Claim
100 words
An apparatus for non-invasively diagnosing a closed air refrigeration system, the system having an evaporator with an inlet and an outlet and a condenser with an intake and an exhaust, the apparatus comprising: a sensing unit selectively positioned near the evaporator inlet for measuring an inlet enthalpy at the evaporator inlet, and near the evaporator outlet for measuring an outlet enthalpy at the evaporator outlet; and a computer means in communication with said sensing unit to compare said inlet enthalpy with said outlet enthalpy to determine a total heat transfer (Q TOT ) for use in diagnosing said refrigeration system.
Claim 11
Dependent Claim
20 words
An apparatus as recited in claim 8 wherein said sensing unit measures a dry bulb temperature and a relative humidity.
Claim 12
Dependent Claim
28 words
An apparatus as recited in claim 8 wherein said computer means compares said inlet enthalpy with said outlet enthalpy to calculate a sensible heat ratio for the evaporator.
Claim 13
Dependent Claim
52 words
An apparatus as recited in claim 8 wherein said sensing unit is an inlet sensing unit positioned near the evaporator inlet and said apparatus further comprises an outlet sensing unit positioned over the evaporator outlet, and wherein said inlet enthalpy and said outlet enthalpy are measured simultaneously by said respective sensing units.
Claim 14
Dependent Claim
80 words
An apparatus as recited in claim 11 further comprising: an intake sensing unit positioned near the condenser intake for measuring an intake enthalpy at the condenser intake; an exhaust sensing unit positioned near the condenser exhaust for measuring an exhaust enthalpy at the condenser exhaust; and a connection for placing said computer means in communication with said intake sensing unite and with said exhaust sensing unit to compare said intake enthalpy with said exhaust enthalpy for diagnosing said refrigeration system.
Claim 15
Dependent Claim
26 words
An apparatus as recited in claim 12 wherein all said sensing units measure a dry bulb temperature and a relative humidity to calculate a respective enthalpy.
Claim 16
Dependent Claim
52 words
An apparatus as recited in claim 13 wherein said computer means compares said evaporator inlet enthalpy with said evaporator outlet enthalpy to calculate a sensible heat ratio for the evaporator and said computer compares said condenser intake enthalpy with said condenser exhaust enthalpy to calculate a sensible heat ratio for the condenser.
Claim 17
Independent Claim
98 words
A method for non-invasively diagnosing a closed air refrigeration system, the system having an evaporator with an inlet and an outlet and a condenser with an intake and an exhaust, the method comprising the steps of: positioning a sensing unit near the evaporator inlet; measuring an enthalpy at the evaporator inlet with said sensing unit; positioning said sensing unit near the evaporator outlet; measuring an enthalpy at the evaporator outlet with said sensing unit; and comparing said evaporator inlet enthalpy with said evaporator outlet enthalpy to determine a total heat transfer (Q TOT ) to diagnose said system.
Claim 18
Independent Claim
98 words
A method for non-invasively diagnosing a closed air refrigeration system, the system having an evaporator with an inlet and an outlet and a condenser with an intake and an exhaust, the method comprising the steps of: positioning a sensing unit near the evaporator inlet; measuring an enthalpy at the evaporator inlet with said sensing unit; positioning said sensing unit near the evaporator outlet; measuring an enthalpy at the evaporator outlet with said sensing unit; and comparing said evaporator inlet enthalpy with said evaporator outlet enthalpy to determine a total heat transfer (Q TOT ) to diagnose said system.
Claim 19
Dependent Claim
65 words
A method as recited in claim 15 further comprising the steps of: positioning a sensing unit near the condenser intake; measuring an enthalpy at the condenser intake with said sensing unit; positioning said sensing unit near the condenser exhaust; measuring an enthalpy at the condenser exhaust with said sensing unit; and comparing said condenser intake enthalpy with said condenser exhaust enthalpy to diagnose said system.
Claim 20
Dependent Claim
35 words
A method as recited in claim 16 wherein said sensing unit comprises an evaporator inlet sensor and an evaporator outlet sensor, and wherein said evaporator inlet enthalpy and said evaporator outlet enthalpy are measured simultaneously.
Claim 21
Dependent Claim
36 words
A method as recited in claim 17 wherein said sensing unit further comprises a condenser intake sensor and a condenser exhaust sensor, and wherein said condenser intake enthalpy and said condenser exhaust enthalpy are measured simultaneously.
Claim 22
Dependent Claim
23 words
A method as recited in claim 18 wherein all said sensing units measure a respective dry bulb temperature and a respective relative humidity.
Claim 23
Dependent Claim
34 words
A method as recited in claim 16 wherein said comparing steps are accomplished using a computer means to calculate a sensible heat ratio of the evaporator and a sensible heat ratio for the condenser.
Claim 24
Dependent Claim
49 words
A method as recited in claim 15 wherein said comparing step is comprises the steps of: subtracting evaporator outlet enthalpy from said evaporator inlet enthalpy to determine a measured heat transfer; and evaluating said measured heat transfer with a rated heat transfer for said system to diagnose said system.
Claim 25
Dependent Claim
41 words
A method as recited in claim 21 further comprising the steps of: determining a measured sensible heat ratio for said system; and comparing said measured sensible heat ratio with a rated sensible heat ratio for said system to diagnose said system.
Claim 26
Dependent Claim
71 words
A method as recited in claim 21 further comprising the steps of: taking a suction line temperature and a liquid line temperature; using said suction line temperature and said liquid line temperature to calculate a measured superheat and a measured subcool for said system; and comparing said measured superheat with a rated superheat for said system, and said measured subcool with a rated subcool for said system to diagnose said system.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-10-10 | 2004-04-10 | 2004-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-10-10 | 2008-04-10 | 2008-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-10-10 | 2012-04-10 | 2012-10-10 | $7700.00 | Window Closed / Lapsed |