Abstract: A device for rolling up a belt of a safety belt assembly for automobiles or the like of the kind employing a locking wheel on the reel spindle for the belt. The locking wheel is moved axially into engagement with a set of teeth on the housing to stop the reel spindle rotatably mounted in said housing. A locking member on the locking wheel first engages another set of teeth on the housing in response to accelerations of the belt in the withdrawal direction to bring the locking wheel to a stop in one of a limited number of known angular positions, whereupon it is moved axially to engage the first mentioned housing teeth with no risk of those teeth coming into tip-to-tip engagement. The locking member may be an inertia body and/or acted on by a separate inertia body, which may be a ring.

Abstract: Inertia type wind up device for safety web belt and having a winding shaft and an inertia blocking wheel rotatably mounted on the winding shaft and which wheel is axially shiftable on the winding shaft upon abrupt acceleration of the shaft against a wind up spring and by means of oblique cam and follower surfaces on the blocking wheel and winding shaft.