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:
Apr. 05, 2005
Filed:
Sep. 23, 2003
Krishnendu Kar, Webster, NY (US);
Sergio Eduardo Garcia, Webster, NY (US);
Krishnendu Kar, Webster, NY (US);
Sergio Eduardo Garcia, Webster, NY (US);
Delphi Technologies, Inc., Troy, MI (US);
Abstract
A method of determining the rubbing friction torque involves characterizing fuel cutoff engine deceleration, and calculating the rubbing friction torque for any combination of engine speed and powertrain temperature is calculated in accordance with a base point rubbing friction torque RFTdetermined at a base powertrain temperature Tand fuel cutoff characterization data. The calibration data characterizing fuel cutoff engine deceleration is obtained by alternately enabling and cutting off engine fuel delivery to cycle the engine speed between specified set points, and measuring and recording the engine deceleration during intervals of fuel cutoff. The rubbing friction torque RFTat a given test temperature Tis calculated according towhere DECELand DECELare the fuel cutoff engine decelerations at the test and base points, respectively, and PFT, and PFTare the pumping friction torques at the test and base points, respectively.