Method for the positioning of an actuator

A method for the positioning, without acknowledgment, of an actuator by a rotor of an electric motor, the motor being controlled as a function of time by a microprocessor, comprising the steps of:

• determining a value K.sub.1 of a proportionality constant K and a corresponding value T.sub.1 of an adjustment time T during a braking of the rotor under a value B.sub.1 of a load B from a first speed of rotation N.sub.2 to a second speed of rotation N.sub.b upon deenergization of the electric motor, for use in a formula
• adjustment path=(K) (T):
• storing the values K.sub.1, T.sub.1, B.sub.1, N.sub.a and N.sub.b ;
• repeating said steps of determining and storing for additional corresponding K.sub.2 . . . K.sub.n, T.sub.2 . . . T.sub.n and B.sub.2 . . . B.sub.n for the braking from speed N.sub.a to speed N.sub.b ;
• measuring a time T.sub.x for braking the rotor from the speed N.sub.a to the speed N.sub.b upon operation of the actuator to obtain a measured value of time T.sub.x ;
• interpolating by linear interpolation between two stored values of time T.sub.n and T.sub.n+1 to obtain a value of the constant K.sub.x corresponding to the measured value of time T.sub.x ;
• and
• positioning the actuator with a braking of the rotor through an adjustment path equal to the product of K.sub.x and T.sub.x.