Patent ID: 6454199
Filing Date: 2002-09-24
Classification: B60R

Abstract:
A pretensioner which is integrated with a webbing take-up device in which a vehicle occupant-restraining webbing is wound on a winding shaft, and at the time of rapid deceleration of a vehicle, which rotates the winding shaft by a predetermined amount in a direction in which the webbing is taken up by using a rack and pinion type driving mechanism, said pretensioner comprising:the winding shaft including: a shaft; and a sleeve portion, one end portion of the sleeve portion being connected to an end portion of the shaft, wherein the driving mechanism comprises: a piston disposed so as to be movable in a cylinder in an axial direction thereof and including a rack portion provided with rack teeth, said piston being provided to move at the time of rapid deceleration of the vehicle; and a pinion disposed so as to engage with the rack teeth and directly connected to an axial end of the winding shaft via a clutch which is connected to the winding shaft, only at the time of rapid deceleration of the vehicle, the pinion including a toothed portion in which pinion teeth engaging with the rack teeth are formed and which covers another end portion of the sleeve portion; and a clutch portion which covers a middle portion of the sleeve portion and formed coaxially and integrally in one piece with the toothed portion wherein a clutch mechanism is positioned at a side of an inner periphery thereof, and wherein roller members are disposed between an inner periphery portion of the clutch portion and an outer periphery portion of the middle portion of the sleeve portion so as to form the clutch mechanism.