US5119638A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air conditioning compressor protection device
Assignee: Delphi Technologies Inc
•
Filing: 1991-03-18
•
Granted: 1992-06-09
•
Expires: 2011-03-18
Abstract
Abstract A method of locating a limit switch (10) on a compressor (12) utilizes thermography for determining the optimum location thereof. A thermograph is produced for normal and abnormal operating modes of the compressor (12). High temperature gradients in the thermograph indicate high rates of temperature increases during compressor failure modes for selecting an optimum location for the limit switch. A bimetal switch (10) is utilized to establish a cut-out temperature for preventing operation of the compressor (12) and a cut-in temperature lower than the cut-out temperature for automatically closing to resume operation of the compressor (12) when returned to normal temperatures.
Inventors
- 👤 Larry D. Cummings
- 👤 Peter S. Eros
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:26
CPC Classifications
F; F04; F04B; F04B49/00; F04B49/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
99 words
A method of positioning a limit switch on a compressor for measuring the temperature of the compressor allowing operation of the compressor during normal operation when the temperature thereof is less than a cut-in temperature and preventing operation of the compressor during abnormal operation when the temperature thereof is greater than a cut-out temperature, the method including the steps of: operating a compressor near failure mode, measuring external thermodynamics of the compressor for establishing a thermal differential location, positioning the limit switch at the thermal differential location to prevent operation of the compressor during abnormal operation of the compressor.
Claim 2
Independent Claim
99 words
A method of positioning a limit switch on a compressor for measuring the temperature of the compressor allowing operation of the compressor during normal operation when the temperature thereof is less than a cut-in temperature and preventing operation of the compressor during abnormal operation when the temperature thereof is greater than a cut-out temperature, the method including the steps of: operating a compressor near failure mode, measuring external thermodynamics of the compressor for establishing a thermal differential location, positioning the limit switch at the thermal differential location to prevent operation of the compressor during abnormal operation of the compressor.
Claim 3
Dependent Claim
21 words
A method as set forth in claim 1 further including measuring the normal external thermodynamics of a compressor during normal operation.
Claim 4
Dependent Claim
25 words
A method as set forth in claim 1 further including thermographing the normal thermodynamics for the compressor during normal operation for producing a normalized thermograph.
Claim 5
Dependent Claim
25 words
A method as set forth in claim 3 further including thermographing the abnormal thermodynamics for the compressor during abnormal operation for producing an abnormal thermograph.
Claim 6
Dependent Claim
27 words
A method as set forth in claim 4 further including comparing the abnormal thermograph to the normal thermograph to identify high temperature gradients indicating the differential location.
Claim 7
Dependent Claim
14 words
A method as set forth in claim 5 further including photographing the normal thermograph.
Claim 8
Dependent Claim
14 words
A method as set forth in claim 6 further including photographing the abnormal thermograph.
References Cited (Backward Citations)
US2978879A
Cited
US3232519A
Cited
US3702065A
Cited
US4059366A
Cited
US4236621A
Cited
JPS5913137A
Cited
US4596518A
Cited
US4733175A
Cited
US4704072A
Cited
US4799578A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-06-09 | 1995-12-09 | 1996-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-09 | 1999-12-09 | 2000-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-09 | 2003-12-09 | 2004-06-09 | $7700.00 | Window Closed / Lapsed |