US4538419A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refrigeration unit controls
Assignee: Carrier Corp
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Filing: 1984-04-06
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Granted: 1985-09-03
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Expires: 2004-04-06
Abstract
Abstract A field test circuit for an electronic control of a refrigeration unit. The test circuit has a field installed test panel with a control switch and a readout device for indicating that portion of the electronic control to be tested. A microprocessor is provided with a logic program that provides coded information regarding the stage of capacity of the refrigeration unit, the operational status of the unit, diagnostic information of the unit, and a test procedure for testing all inputs and outputs of the microprocessor.
Inventors
- 👤 Richard G. Lord
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:30
CPC Classifications
G; G01; G01R; G01R31/00; F; F25; F25B; F25B49/00; F25B49/02; G05; G05D; G05D16/00; G05D16/20; G05D16/2006; G05D16/2013; G05D16/2022; F25B2400/00; F25B2400/06; F25B2400/07; F25B2400/075
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
115 words
A method of testing the electronic controls of a refrigeration unit from a built in field test panel having a digital display, a digital display control switch, a plurality of condition sensor means, and a test logic circuitry having a preprogrammed procedure comprising the steps of: electrically connecting output signals of the plurality of condition sensor means to the inputs of a microprocessor control; generating a series of test signals from the preprogrammed procedure of the test logic circuitry of the microprocessor; operating the digital display control switch to sequentially advance said series of test signals; and displaying the series of test signals on the digital display as the digital display control switch is operated.
Claim 2
Independent Claim
115 words
A method of testing the electronic controls of a refrigeration unit from a built in field test panel having a digital display, a digital display control switch, a plurality of condition sensor means, and a test logic circuitry having a preprogrammed procedure comprising the steps of: electrically connecting output signals of the plurality of condition sensor means to the inputs of a microprocessor control; generating a series of test signals from the preprogrammed procedure of the test logic circuitry of the microprocessor; operating the digital display control switch to sequentially advance said series of test signals; and displaying the series of test signals on the digital display as the digital display control switch is operated.
Claim 3
Dependent Claim
42 words
A method as set forth in claim 1 wherein said series of test signals are displayed as coded numerals on the digital display at the test panel and a series of step numerals are displayed sequentially, one prior to each test signal.
Claim 4
Dependent Claim
30 words
A method as set forth in claim 1 wherein said generating, operating and displaying of said series of test signal occurs only during an initialization stage of the electronic controls.
Claim 5
Dependent Claim
22 words
A method as set forth in claim 3 wherein said initialization stage occurs generally within two minutes of starting the refrigeration unit.
References Cited (Backward Citations)
US4146085A
Cited
US4411139A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-02 | 1989-03-04 | 1989-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-02 | 1993-03-04 | 1993-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-02 | 1997-03-04 | 1997-09-03 | $7700.00 | Window Closed / Lapsed |