US Patent 7669499 Arrester device for a closing apparatus

The present disclosure relates to an arrester device for closing apparatus, such as doors, comprising a worm gear rotationally fixedly connected to an output shaft serving as a winding shaft and a self-locking worm which is in communication with an input shaft. In accordance with the present disclosure, an auxiliary worm gear is seated on an eccentric region of the output shaft with clearance, with the auxiliary worm gear having an eccentricity of the same amount as the output shaft and being assembled such that the eccentricities are cancelled with respect to the axis of the output shaft, with the auxiliary worm gear being able to follow the movement of the worm gear without load via its toothed region.