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US4358933A Expired / Lapsed US ⏱️ 0.0 years remaining

Household refrigerator defrost system

Assignee: General Electric Co
•
Filing: 1981-01-19
•
Granted: 1982-11-16
•
Expires: 2001-01-19
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Abstract

Abstract A refrigerator including a compressor, an evaporator and a condenser with a temperature control to energize and de-energize the compressor. There is an electrical defrost heater for periodically warming the evaporator to defrost temperatures which is energized and de-energized by an electrical motor-driven defrost control timer having a predetermined period of run time between initiation of each successive defrost cycle. The defrost control timer is energized to run only when the compressor is energized and the defrost control timer is delayed in running for a period of time each time the compressor is energized.

Inventors

  • 👤 Julius B. Horvay

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 07:15
CPC Classifications
F; F25; F25D; F25D21/00; F25D21/002; F25D21/008; F25B; F25B2600/00; F25B2600/23; F25D2700/00; F25D2700/02; F25D2700/12

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 105 words
In a refrigerating system including a compressor, an evaporator and a condenser; (a) temperature control means to energize and de-energize the compressor, (b) an electrical defrost heater for periodically warming the evaporator to defrost temperatures, (c) an electrical motor-driven defrost control timer to energize and de-energize the defrost heater and having a predetermined period of run time between initiation of each successive defrost cycle, (d) means to energize and run the defrost control timer only when the compressor is energized, and (e) means to automatically delay the running of the defrost control timer for a fixed period of time each time the compressor is energized.
Claim 2
Dependent Claim 105 words
In a refrigerating system including a compressor, an evaporator and a condenser; (a) temperature control means to energize and de-energize the compressor, (b) an electrical defrost heater for periodically warming the evaporator to defrost temperatures, (c) an electrical motor-driven defrost control timer to energize and de-energize the defrost heater and having a predetermined period of run time between initiation of each successive defrost cycle, (d) means to energize and run the defrost control timer only when the compressor is energized, and (e) means to automatically delay the running of the defrost control timer for a fixed period of time each time the compressor is energized.
Claim 3
Dependent Claim 54 words
In the refrigerating system of claim 1 wherein the means to delay the running of the defrost control timer is an electro-mechanical timer that runs for a set period of time after energization of the compressor and at the end of the run period, switch means are actuated to energize the defrost control timer.
Claim 4
Dependent Claim 21 words
In the refrigerator of claim 2 wherein the delay timer is reset prior to the next successive energization of the compressor.

References Cited (Backward Citations)

US3812306A Cited
US4056948A Cited
US4197717A Cited
US4156350A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-11-15 1986-05-17 1986-11-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-11-15 1990-05-17 1990-11-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-11-15 1994-05-17 1994-11-16 $7700.00 Window Closed / Lapsed

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