Patent ID: 8286518

Claim:
A drive device coupled between a stationary component and a hinged movable component, the drive device comprising: a first fastening element connectable to one of the stationary component and the hinged movable component; a housing tube, the housing tube configured to be axially moveable relative to the first fastening element; a second fastening element attached to the housing tube at an end opposite the first fastening element, the second fastening element being connectable to the other of the stationary component and the hinged movable component; a spindle drive mounted in the housing tube, the spindle drive comprising: a threaded spindle having an external thread; and a spindle nut mounted on the threaded spindle and coupled to the first fastening element, wherein the spindle drive is configured to move the first fastening element and the housing tube axially relative to each other via the spindle nut; a rotary drive configured to rotate the spindle; a stationary magnetic field sensor coupled to the housing tube for detecting a stroke position of the first fastening element; a cylindrical externally threaded part mounted on the threaded spindle, the thread of the cylindrical externally threaded part being of a finer pitch than the thread of the threaded spindle; and a circular internally threaded part, wherein the thread of the internally threaded part engages the thread of the cylindrical externally threaded part; a permanent magnet coupled to the cylindrical internally threaded part for movement in a longitudinal direction, wherein rotation of the threaded spindle moves the permanent magnet along a sensing area of the stationary magnetic field sensor.