Method for determining the position of an element driven by the drive shaft of a direct current motor

A method for determining the position of a movable element to be driven by the drive shaft of a direct current motor along a travel segment between first and second end positions, the method comprising:

• counting current ripples contained in an armature current signal of the direct current motor as the drive shaft of the direct current motor rotates to drive the movable element;
• determining the position of the movable element along the travel segment based on the counted current ripples;
• actuating the direct current motor to move the movable element into the first end position when the movable element is to be moved out of the first end position towards the second end position;
• resetting the counted current ripples to a reset value after the direct current motor has been actuated to move the movable element into the first end position and the position of the movable element is at the first end position such that the reset value corresponds to the position of the movable element being at the first end position;
• and
• actuating the direct current motor to move the movable element out of the first end position towards the second end position after the counted current ripples has been reset to the reset value.