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:
May. 23, 1989
Filed:
Jul. 13, 1987
Patricia Duenes, Irvine, CA (US);
Richard L Kenyon, Irvine, CA (US);
John N Scapes, Schamburg, IL (US);
Eugene H Schild, Des Plaines, IL (US);
Arthur P Strong, Prospect Heights, IL (US);
Parker Hannifin Corporation, Cleveland, OH (US);
Abstract
Apparatus for detecting frost buildup on an evaporator (34) of a refrigeration system (10) includes an air velocity sensor (42) in the air flow path. The sensor is connected to an analog to digital converter (46) which delivers binary signals representative of air velocity to a microcomputer (50) which includes a processor and a memory. Microcomputer (50) is programmed to prompt an operator through a screen (56) at a user station (52) to input an air flow reduction factor at a keyboard (54). The microcomputer uses the air flow reduction factor and the velocity sensed when the evaporator is fully defrosted to calculate a defrost initiation value. When the air velocity sensed at the sensor is no longer greater than the initiation value the microcomputer generates a defrost initiation signal. The microcomputer also includes a timer clock and periodically prints at a printer (58) the time and the velocity sensed.