Method and apparatus for controlling electromechanical components

Abstract

The invention relates to a control method for an electromechanical element for positioning an element to be driven which is at least temporarily in contact with said electromechanical element, wherein voltage pulses are applied to said electromechanical element in step mode and said respective voltage The pulse has at least two periods, wherein in said one period an average slower temporal change in voltage occurs and in said other period an average faster time change in voltage occurs, and at least in the period defined as the drive period During a part of the period of the average slower time change of the voltage, the element to be driven is caused to be driven by the electromechanical element by static friction between the electromechanical element expanding or contracting in the driving direction and the element to be driven. The element is brought into motion, and at least during a portion of said period defined as an average faster temporal change of said voltage over a period of relative movement, by said electromechanical element contracting or expanding opposite to the direction of actuation and said to-be-actuated Relative movement between the electromechanical element and the element to be driven occurs due to sliding friction between the elements, so that the element to be driven performs discrete steps in the driving direction using the respective voltage pulses, and the method A controller and a driver electrically connected to the controller are also included. According to the invention, the controller transmits a time-continuous current to the driver, and the driver transmits a corresponding charging current to the electromechanical element electrically connected to the driver, wherein the controller relies on the The difference between the actual position and the target position of the element to be driven is continuously adapted to the time-continuous current, and the drive is performed independently of the controller but on the voltage acting on the electromechanical element. Electrically isolated from the controller. The invention also relates to a corresponding device for carrying out the method according to the invention.

Description

technical field [0001] The invention relates to a method for controlling an electromechanical element, in particular a piezoelectric actuator, and a corresponding device for carrying out this method. Background technique [0002] A method is known for controlling a piezoelectric actuator for a driver, wherein the piezoelectric actuator is supplied with a saw-tooth-shaped or ramp-shaped voltage with flat and steep edges by the driver, wherein the actuation The actuator completes a correspondingly slower expansion or contraction in the phase of the slower voltage change, i.e. in the region of the flat edge (also known as the stick-phase), and the element to be driven which is in frictional contact with the actuator can This slower movement is followed due to stiction and thus produces a driving movement or a driving step, whereas in the phase of rapid voltage changes, i.e. in the region of steep edges (also called the slip phase (Slip-Phase)), resulting in The actuator comple...

AI Technical Summary

Problems solved by technology

This complicates the implementation of the corresponding controller

Here, switching between modes corresponds to a discontinuity, which leads to a corresponding and unfavorable discontinuity in the control signal

Finally, the methods known from the prior art not only need to be used to check whether it is necessary to switch to another mode, but also require a certain time for the mechanical part of the drive to decay accordingly in the discontinuous stepping mode, resulting in an overall relatively slow Control Method

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