Patent ID: 7323798

Claim:
An electrodynamic direct drive and more particularly a linear drive, comprising an armature adapted to travel within a housing, a drive system for moving such armature in relation to said housing, such drive system having two drivingly cooperating drive means, able to be moved in relation to each other, in the form of a coil system with at least one coil, and a magnet system with at least one permanent magnet in order to move a load driver coupled with the armature, wherein a displacement measurement space is defined by an end face of the armature from which the load driver does not project and at least one of the walls of the housing and the surface of the internally placed drive means, and a sensor disposed within the displacement measurement space adapted to detect the position of the armature within the displacement measurement space by way of electromagnetic waves, the distance of the movable armature from the sensor being able to be measured on the basis of the transit time of electromagnetic waves, the end face and the inner face of the displacement measurement space comprising an electrically conductive surface material in order to provide a reflecting surface for an optimum measuring function of the sensor.