Patent ID: 8040082

Claim:
A linear actuator comprising: an electric motor, a transmission, a spindle, a spindle nut, where the spindle nut and the spindle between a first and a second point, indicating the length of stroke, can move axially in proportion to each other, depending on whether the spindle or the spindle nut is driven around via the transmission, incremental position sensors for determining the direction of rotation and position of the spindle nut/the spindle, a control unit comprising a micro processor for receiving signals from the position sensors and on this basis determining the position, and a power supply, wherein an initiating procedure, where the nut/spindle is moved from a first point on the spindle/nut to a second point on the spindle/nut for the first time, the number of pulses derived from the incremental position sensors are registered as a measurement for the length of stroke, and the position is subsequently determined in relation thereto, and the control unit is active before, during and after the operation of the motor.