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. 21, 1984
Filed:
Nov. 09, 1981
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F25D / ;
U.S. Cl.
CPC ...
62155 ; 62156 ; 62234 ; 219497 ; 338 / ;
Abstract
A defrosting apparatus for removing frost deposited on a cooler of a refrigerator or an air conditioner employs a defrosting heater exhibiting a positive temperature coefficient of resistance which changes sharply at a specific temperature. A specific rate of change of the heater current of the defrosting heater is detected, and on the basis of the detected current change rate, stopping or starting of current supply to the defrosting heater is controlled. The defrosting heater is an organic type heater or an inorganic ceramic type heater possessing the function of self-temperature control.