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:
Jan. 10, 2017
Filed:
Nov. 17, 2010
David K. Hinde, Atlanta, GA (US);
John D. Bittner, Bethlehem, GA (US);
Shitong Zha, Conyers, GA (US);
Joseph R. Poland, Decatur, GA (US);
David K. Hinde, Atlanta, GA (US);
John D. Bittner, Bethlehem, GA (US);
Shitong Zha, Conyers, GA (US);
Joseph R. Poland, Decatur, GA (US);
Hill Phoenix, Inc., Conyers, GA (US);
Abstract
A cascade refrigeration system includes an upper portion having at least one modular chiller unit that provides cooling to at least one of a low temperature subsystem having a plurality of low temperature loads, and a medium temperature subsystem having a plurality of medium temperature loads. The modular chiller unit includes a refrigerant circuit having at least a compressor, a condenser, an expansion device, and an evaporator. An ammonia refrigerant mixed with a soluble oil circulates within the refrigerant circuit. A control device may be programmed to modulate the position of the expansion device so that a superheat temperature of the ammonia refrigerant near an outlet of the evaporator fluctuates within a substantially predetermined superheat temperature range to positively return soluble oil from the evaporator to the compressor.