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:
Oct. 06, 1992
Filed:
Feb. 10, 1992
Laurence R Brickner, Marathon, NY (US);
David A Christiansen, Bloomington, MN (US);
Thermo King Corporation, Minneapolis, MN (US);
Abstract
A method of determining if the refrigerant charge in a refrigeration system is within an acceptable range, including the step of developing a model evaporator temperature-versus-time signature for a system known to have a recommended refrigerant charge level. The model developing step includes the steps of isolating an evaporator from a space to be conditioned by the system, operating the system in a cooling mode to cool the evaporator, trapping refrigerant in the cooled evaporator to introduce an instability into the cooling cycle, and continuing the cooling mode for a time sufficient for a system having an acceptable charge level to recover from the trapping step. A test signature is then provided for a system to be checked, using steps similar to those used to develop the model signature, and the test signature is compared with the model signature to determine if the refrigerant charge is within an acceptable range.