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:
Jul. 15, 2003
Filed:
Jul. 11, 2000
John E Seem, Glendale, WI (US);
Jonathan D West, Brown Deer, WI (US);
Willem Huisman, Veenwouden, NL;
Johnson Controls Technology Company, Plymouth, MI (US);
Abstract
A refrigeration system ( ) has a compressor ( ) that forces a refrigerant to flow in a loop between an evaporator ( ) and a condenser ( ). The present method controls the speed of a condenser fan ( ) in response to the condenser temperature. In a first control state, the speed of the fan ( ) is varied in response to the condenser temperature. In a second state, the fan ( ) is turned on and off by a pulse width modulated signal that has a duty cycle which varies in response to the condenser temperature. A transition occurs from the first state to the second state when the fan ( ) operates at the slowest possible speed for a predetermined period while the condenser temperature is below a desired value. A transition occurs from the second state to the first state when the duty cycle is at 100% for a given period and the condenser temperature is above the desired value.