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:
Mar. 04, 1980
Filed:
Feb. 14, 1977
Francis J Sisk, Apollo, PA (US);
Electric Power Research Institute, Inc., Palo Alto, CA (US);
Abstract
An evaporator heat exchanger is disposed within a vertical, rectangular duct. A heater for defrosting the heat exchanger is disposed beneath the exchanger. During the defrost cycle heated air rises by convection vertically through the heat exchanger. The defrost cycle is initiated by sensing the pressure drop across the heat exchanger. This is done by extending a small diameter pipe through a wall of the duct downstream of the heat exchanger so that an air current is drawn through the pipe during normal operation of the system. A constant energy output heater heats the air current in the pipe so that the temperature of the heated current remains constant so long as the air volume flowing in the pipe remains constant. As the pressure drop across the heat exchanger increases as a result of an increasing frost buildup, relatively more air is drawn through the pipe. As a result the temperature of the heated air in the pipe decreases. A control switch is adjusted so that it initiates the defrost cycle whenever the air current temperature reduction in the pipe reaches a predetermined value.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile