METHOD FOR DETERMINING THE POSITION OF AN ELEMENT DRIVEN BY THE DRIVE SHAFT OF A DIRECT CURRENT MOTOR

摘要

A method for determining the position of an element drivable by a motor within a travel segment between first and second positions. The method includes energizing a motor to drive the element along the travel segment. Current ripples contained in an armature current signal of the motor are counted as the motor drives the element. The position of the element along the travel segment is determined as a function of the counted current ripples. The motor is de-energized once the position of the element is within a certain distance of the first position if the element is to be driven into the first position. The motor is then re-energized to drive the element into the first position. The counted current ripples is set to a reset value after the element has been driven into the first position such that the reset value corresponds to the first position.