Patent ID: 8165762
Filing Date: 2012-04-24
Classification: F16H

Abstract:
1. A method to operate a valve system of a drive train of a vehicle transmission system with a valve system unit and an engaging electro-magnetic activator unit, whereby through the valve system unit a hydraulic pressure value of the hydraulic system in the transmission of a vehicle's drive train can be set, depending on a pulse-width modulated current signal (i_EDS), present at the electro-magnetic activator unit, and at least one of an amplitude (A) and a pulse duration (pw 1 ) of a pulse-width modulated signal, during a Dither-Modulation which is, by maintaining the pressure value to be set, whereby the valve system's lengthwise movable anchor and the connected valve shaft are now exposed to a vibration, thereby characterized that the Dither-Modulation will be activated or deactivated depending on gear shifts that are activated within a range of gear ratios, the range of gear ratios being pre-defined by a shifting strategy.