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. 07, 2009
Filed:
May. 25, 2006
Jy-jen F. Sah, West Bloomfield, MI (US);
Bryan R. Snyder, Waterford, MI (US);
Jy-Jen F. Sah, West Bloomfield, MI (US);
Bryan R. Snyder, Waterford, MI (US);
GM Global Technology Operations, Inc., Detroit, MI (US);
Abstract
The invention comprises a method, an article, and a control system for controlling a powertrain having a main and an auxiliary hydraulic pump, with each pump operative to supply hydraulic fluid to a hydraulic circuit of the transmission. It includes determining a main pressure and a desired main pressure, and controlling the auxiliary hydraulic pump. Determining a main pressure in the hydraulic circuit comprises estimating hydraulic pressure. The auxiliary pump is controlled to an operating speed. Control of flow from the auxiliary and main pumps can comprise an exclusive 'either-or' flow, or a blended flow.