Abstract: A belt retractor for a motor vehicle seat belt device, with a rotatably mounted belt reel onto which a seat belt is wound, and a belt tensioner with a drive wheel (1), which drives the belt reel in the event of an activation. A positively controlled tensioner coupling transfers the drive movement from the drive wheel (1) onto the belt reel. At least one coupling pawl (2,3) mounted on the drive wheel (1) and which is moved into and out of engagement with a toothing (20) rotationally fixed in relation to the belt reel to establish and disconnect a rotational connection of the drive wheel (1) with the belt reel. A friction ring (4) has a control arm (11) coupled with the coupling pawl (2,3), wherein in the event of an activation of the belt tensioner, the friction ring (4) performs a relative movement to the drive wheel (1) by frictional forces and, controls via the control arm (11) the movement of the coupling pawl (2,3) into engagement and disengagement with the toothing (20).

Abstract: A belt retractor for a motor vehicle seat belt device, with a rotatably mounted belt reel onto which a seat belt is wound, and a belt tensioner with a drive wheel (1), which drives the belt reel in the event of an activation. A positively controlled tensioner coupling transfers the drive movement from the drive wheel (1) onto the belt reel. At least one coupling pawl (2,3) mounted on the drive wheel (1) and which is moved into and out of engagement with a toothing (20) rotationally fixed in relation to the belt reel to establish and disconnect a rotational connection of the drive wheel (1) with the belt reel. A friction ring (4) has a control arm (11) coupled with the coupling pawl (2,3), wherein in the event of an activation of the belt tensioner, the friction ring (4) performs a relative movement to the drive wheel (1) by frictional forces and, controls via the control arm (11) the movement of the coupling pawl (2,3) into engagement and disengagement with the toothing (20).

Abstract: A safety belt retractor, especially in vehicles, is provided that includes a belt shaft as a carrier for a belt that is wound thereon and a vehicle sensitive and/or belt sensitive controllable block device for the belt shaft. The block device includes a force limiting device, effective in the event of a block event, the force limiting device having a viscous medium-filled housing with at least one fixedly positioned contour and a counter-contour that is rotatably displaceable in response to a block event, so that the relative movement between the contour and the counter-contour forces the viscous medium between the surfaces arranged for this purpose. The level of the force limitation applied by the force limitation device is adjustably settable as a function of the parameters associated with the buckled-in passengers via a variation of the inner pressure in the viscous medium-filled housing.

Abstract: A safety belt retractor is provided that has a force limiting device that operates with a viscous medium. The belt shaft is adapted to be coupled with a central shaft that carries a socket type piston that is movable relative to a fixed counter socket, whereby due to relative movement the viscous medium is forced between the socket type piston and the counter sockets, thereby effecting a force limitation.