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:
Aug. 29, 1989
Filed:
Dec. 29, 1987
Daniel S Query, Antioch, TN (US);
Whirlpool Corporation, Benton Harbor, MI (US);
Abstract
A fiber optic frost sensor for use in a refrigerating apparatus having evaporator coils is used to determine when ice or frost has accumulated on the evaporator coils to an extent that the air around the evaporator coils cannot be cooled efficiently. The frost sensor includes a fiber optic cable located adjacent to the evaporator coils, the fiber optic cable extending between a light transmitter and a light receiver. As ice and frost accumulate on the evaporator coils, the ice and frost also accumulate on the outer surface of the fiber optic cable resulting in a change in the amount of light traveling from the transmitter to the receiver through the fiber optic cable. When the amount of light received by the receiver changes a preselected amount, the receiver determines that a defrost cycle needs to be initiated to melt the accumulated ice or frost. In one embodiment, a serpentine fiber optic cable is looped along the evaporator coils. In another embodiment, notches or the like are provided in the external surface of the fiber optic cable. In yet another embodiment, a segmented fiber optic cable is used. In order to properly position the fiber optic cable adjacent to the evaporator coils, the fiber optic cable can be preassembled into a mounting bracket that snaps onto the evaporator coils.