Patent ID: 6575498
Filing Date: 2003-06-10
Classification: B60R

Abstract:
A webbing retractor which includes a take-up shaft for taking up a webbing, a pretensioner mechanism which has a substantially hollow cylinder and a piston which is provided within said cylinder and with which a fitting portion which substantially fits into the inner wall of said cylinder is provided, and in which when a vehicle is in an emergency, gas is supplied within said cylinder and below said fitting portion such that said piston is moved upward due to the gas pressure to rotate said take-up shaft in the direction in which said webbing is taken up, and a force limiter mechanism having a deformable energy absorbing member in which when a vehicle is in an emergency, said energy absorbing member is deformed due to a load of a vehicle occupant upon said webbing such that said take-up shaft is rotated in the direction in which said webbing is pulled out to move said piston downward,said pretensioner mechanism comprising: a gas passing portion which is provided at said piston and from which said gas can be discharged from below to above said fitting portion; and a closing device including a retaining means and a sealing means which is provided so as to correspond to a hole portion of said gas passing portion, and substantially closes said gas passing portion under normal circumstances, and maintains the state in which said gas passing portion is substantially closed when said piston is moved upward by said pretensioner mechanism, and which opens said gas passing portion when said piston is moved downward by said force limiter mechanism by the action of said retaining means releasing said sealing means.