Safety belt tensioning device

Claim 1

Apparatus for tensioning a restraining device when actuated, comprising, in combination: a. piston means; b. cylinder means, surrounding said piston means, for applying a force to cause said piston means to move therein upon actuation, said cylinder means including a propellant charge for applying said force when released, said cylinder means being further provided with at least one discharge opening for controlling the velocity of said piston means; c. actuatable sensor means for releasing said propellant charge when actuated; d. intermediate means including a piston connecting rod, connecting said piston means to the restraining device, for tensioning the restraining device upon movement of said piston; and e. return stop means acting directly on said piston means for maintaining tension in the restraining device after tensioning by said intermediate means, said return stop means including: 1. at least two gripping jaws surrounding said connecting rod, the outer diameter of said gripping jaws being conically tapered such that said outer diameter is reduced in the direction of locking, and 2. jaw closing means surrounding said gripping jaws, the inner diameter of said jaw closing means being adapted to the contour of said outer diamter of said gripping jaws.