Patent ID: 6253632
Filing Date: 2001-07-03
Classification: E06B,F16H,Y10T

Abstract:
A motion transforming apparatus transforming an angular motion into an angular function thereof, comprising an electric motor that is placed in a stationary tube and has an output, said output being coupled to a screw drive which includes two screws with different pitches and two nuts and a guide mechanism, the output of the electric motor is coupled to a driving screw transmission which includes a driving screw and a driving nut cooperating with one another, whereby one of said driving screw and driving nut is rotatably connected to said output and the other one of said driving screw and said driving nut being arranged non-rotatably but axially movable; said non-rotatably but axially movable driving screw or driving nut being drivingly connected to a guide rod so as to impart a non-rotatable but axial motion to said guide rod; said guide rod being linearly guided in said guide mechanism and connected to a driven screw so as to form a single piece therewith; said non-rotatable but axial movable driven screw cooperating with a rotatable but axially immovable driven nut whereby said linear motion of said guide rod and said driven screw imparts via its pitch in turn a rotational motion to said rotatable but axially immovable driven nut; said electric motor, said driving screw, said driving nut, said guide rod, said driven screw, said driven nut and said guide mechanism being arranged in-line on a common axis in said stationary tube; said electric motor being fixed at one end of said stationary tube and said driven nut being rotatably but axially immovable coupled to the other end of said stationary tube; said driving and driven screw having the different pitches, whereby the pitch of said driven screw is high enough that the whole screw transmission is self-locking with respect to an external torque.