Abstract: A safety belt retractor with a belt tensioner acting on a belt reel via a first coupling mechanism includes a housing, a vehicle and/or belt webbing-sensitive automatic blocking device for the belt reel and a second coupling mechanism which establishes a force flow between the housing and the belt reel after the belt has been tensioned and upon movement of the belt reel in the direction of belt unwinding in the event of the belt reel. The first coupling mechanism is connected on the power output side and the second coupling mechanism is connected on the power input side to the first end of a torsion bar whose second end is connected to the belt reel. A deactivation device connected to the second coupling mechanism is provided for the automatic blocking device.

Abstract: The seat belt retractor has a belt reel (12) rotatably mounted in a frame (10). A vehicle-sensitive latching mechanism includes a control disk (64) connected to the belt reel (12), rotation of which is lockable by means of the vehicle-sensitive inertial sensor (71, 71a, 73a, 75a). A belt tensioning drive engages the first axial end of a torsion bar (30), the second end of which is drivingly coupled to the belt reel (12). After belt tensioning the first end of said torsion bar (30) is blocked on the frame (10). Under the load subsequently introduced via the belt webbing (14) the torsion bar (30) is twisted about its axis for conversion of energy. The control disk (64) is connected to the belt reel (12) via a torque-limiting coupling (60, 62, 68, 74, 78; 92 to 106).

Abstract: To avoid an undesirable locking of the belt spool on sudden taking up of a relatively great length of webbing on the belt spool, a means is provided which from a predetermined value of the external diameter of the webbing coil on the belt spool onwards prevents activation of the vehicle and webbing-sensitive blocking mechanism. This is achieved by means of a synchronization gear which is coupled non-rotatably to the belt spool and from a predetermined value of the external diameter of the webbing coil onwards comes into engagement with a coupling gear which simultaneously comes into engagement with an external toothing of a control disk, so that any relative movement between the control disk and the belt spool is prevented, thereby disabling activation of the blocking mechanism.

Abstract: A safety belt retractor is provided with a dual-tension comfort function. Between the belt reel and housing a retractor spring and an auxiliary spring of weaker spring force than said retractor spring are connected functionally in series via a ratchet wheel. The rotation of said ratchet wheel is selectively blockable by a pawl. The transition between diminished and undiminished tension in the webbing takes place gently, jerk-free and silently because the rotation of the ratchet wheel is inhibited by a brake means as long as the auxiliary spring is not completely or at least almost completely tensioned. Said brake means includes lever-like engagement elements which are pivotally mounted on the ratchet wheel and which are moved by the pressure exerted by the outer periphery of the auxiliary spring in the axial direction to activate a friction brake.