Verfahren zum Steuern des Übersetzungsverhältnisses eines Riemengetriebes

摘要

A belt drive continuously variable transmission has a primary pulley operatively connected to an engine and a secondary pulley operatively connected to wheels of a motor vehicle, hydraulic cylinders for changing effective diameters of both pulleys, and a transmission ratio control valve for producing a primary pressure applied to the primary cylinder for controlling transmission ratio. An anti-lock brake system is provided on the vehicle. A deceleration of the vehicle is calculated based on vehicle speed. Time from an end of operation of the antilock brake system until the vehicle stops is calculated based on the calculated deceleration and to the vehicle speed. Furthermore, downshifting speed necessary to increase the actual transmission ratio to a maximum transmission ratio before the vehicle stops is calculated based on the calculated time until the vehicle stops and to the actual transmission ratio. In place of the transmission ratio changing speed, the calculated downshifting speed is used when the operation of the antilock brake system ends.