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. 05, 2013
Filed:
Sep. 12, 2008
Lawrence P. Ziehr, Clarkston, MI (US);
Gregory A. Major, Farmington Hills, MI (US);
Lawrence P. Ziehr, Clarkston, MI (US);
Gregory A. Major, Farmington Hills, MI (US);
GM Global Technology Operations LLC, Detroit, MI (US);
Abstract
A method and system for removing oil accumulation from refrigerant lines of a vehicle HVAC system having multiple refrigerant loops each having an evaporator is disclosed. The method for operating the system may comprise the steps of: monitoring a flow rate through at least one of the refrigerant loops; determining if the flow rate through any of the at least one refrigerant loops being monitored is below a predetermined flow rate for greater than a predetermined time limit; monitoring for an indication of imminent vehicle operation; and if the indication of imminent vehicle operation is detected and the flow rate through any of the at least one refrigerant loops being monitored is below the predetermined flow rate for greater than the predetermined time limit, opening a valve to allow for maximum flow through the at least one refrigerant loop.