Patent ID: 7506560
Filing Date: 2009-03-24
Classification: A47B,F16D,F16H,H02K,Y10T

Abstract:
1. An actuator comprising a reversible motor, a transmission operatively connected to the motor, a spindle with threads, said spindle being operatively connected to the transmission to rotate the spindle multiple revolutions, a movable adjustment element having threads in engagement with the threads of the spindle for moving the movable adjustment element along the spindle, a cylindrical part which is static, fixed and immovably mounted relative to the motor, a rotating element attached to an end of the spindle and rotatable by the motor, a coil spring with a first end secured to the rotating element, said coil spring being arranged on the cylindrical part and with a direction of winding such that the spring exerts a braking effect on the adjustment element in one direction of movement thereof in that the spring is tightly wrapped around the cylindrical part, said braking effect being adapted such that it may be overcome by the motor, and wherein an axis of the coil spring is in alignment with an axis of the rotating element so that the spring is carried along in the rotation on the cylindrical part.