The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 27, 1996
Filed:
Jun. 13, 1994
Joseph M Szynal, Laporte, IN (US);
Beth A Maddix, Lincoln Township, Berrien County, MI (US);
Ronald W Guess, Evansville, IN (US);
Whirlpool Corporation, Benton Harbor, MI (US);
Abstract
A defrost cycle controller for modifying the total length of time a compressor operates before a defrost cycle is initiated, wherein the time the compressor is on between defrost cycles is referred to herein as a frost accumulation period. A microprocessor includes means for deenergizing the compressor and coupling the defrost heater to a power supply when a continuous compressor run time exceeds a predetermined demand defrost time. The microprocessor further includes means for determining the time required to actually defrost the evaporator during a defrost operation, referred to herein as a defrost time, and means for modifying the frost accumulation period in response to the time to complete the defrost operation. The present invention further provides a method for determining the time required to actually defrost the evaporator during a first defrost operation, referred to herein as a first defrost time, and for determining the time required to actually defrost the unit during a second defrost operation, referred to herein as a second defrost time, wherein the second defrost operation is immediately subsequent to the first defrost operation. An inference is made as to whether the frost accumulating period should be modified before initiating the next defrost operation in response to the first defrost time and the second defrost time are provided and the frost accumulating period is modified if required.