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. 24, 2012
Filed:
Feb. 11, 2009
Christian Popp, Kressbronn, DE;
Thilo Schmidt, Meckenbeuren, DE;
Klaus Steinhauser, Kressbronn, DE;
Christoph Braun, Uhldingen-Muhlhofen, DE;
Christian Popp, Kressbronn, DE;
Thilo Schmidt, Meckenbeuren, DE;
Klaus Steinhauser, Kressbronn, DE;
Christoph Braun, Uhldingen-Muhlhofen, DE;
ZF Friedrichshafen AG, Friedrichshafen, DE;
Abstract
A method of operating a valve system of a transmission comprising part of the vehicle drive train through a valve unit and said valve unit's electro-magnetic activator configuration. In a transmission's hydraulic system and is part of the vehicle drive train, its hydraulic pressure value (p_EDS) can be employed and adjusted through a valve unit configuration by applying a pulse-width-modulated current signal (i_EDS) to the electro-magnetic activator system. The pulse-width modulated current signal (i_EDS) and its amplitude (A) and/or its pulse duration (pw) will periodically change, during the applied Dither-Modulation, by maintaining the required pressure value (p_EDS) at the same time, whereby a lengthwise movable anchor, which is attached a valve shaft of the valve system, receives hereby an imposed vibrating oscillation. According to the invention, the Dither-Modulation is activated or deactivated during pre-defined operating conditions of the vehicle drive train.