| 主权项 |
1. A retractor for a seat belt system for a vehicle comprising:
a spindle on which a webbing is wound; a frame for pivotally holding the spindle; a spindle locking system means for stopping rotation of the spindle rotating in a webbing drawing out direction when at least one of the two following criteria is met:
a rotational acceleration of the spindle is greater than a first predetermined value when the webbing is accelerated in the drawing out direction; anda deceleration of the vehicle is greater than a second predetermined value; a motor which generates a motor torque to rotate the spindle in the winding direction; a torque transmitting mechanism system which transmits the motor torque to the spindle, a control system for controlling the torque generated by the motor according to a seat belt fastening state and a dangerous state, the seat belt fastening state being one of a fastened seat belt state and a non-fastened seat belt state; a winding spring which generates a spring torque to rotate the spindle in a winding direction in which the webbing is wound onto the spindle, the winding spring being connected to the spindle at all times so as to transmit the generated spring torque to the spindle and being set to generate a spring torque insufficient for completely winding the webbing onto the spindle absent any other forces while the seat belt fastening state is the non-fastened seat belt state; a torque transmission cushioning system for cushioning a torque transmission by an elastic member arranged between the motor and the spindle, wherein when the motor torque is transmitted to the spindle, a sudden change in the motor torque is not transmitted to the spindle as a sudden change in torque, and wherein when the motor torque is transmitted to the spindle, a sudden force given to the spindle in the drawing out direction is not transmitted to the motor as a sudden change in force, the torque transmission cushioning system configured to be activated and deactivated by a clutch, a seat belt fastening state detecting system incorporated into a buckle, the seat belt fastening detection system being operable to detect the seat belt fastening state based on whether or not a tongue is engaged with the buckle; and a dangerous state detecting system for detecting whether or not the vehicle is in the dangerous state, wherein the motor is operated repeatedly, and the spring torque is configured to maintain a lower rotary speed of the spindle than the motor torque, wherein the control system is configured to compare an actual amount of drawing of the webbing determined by a count of an angular counter with a predetermined amount of drawing of the webbing when the seat belt fastening state is the non-fastened seat belt state, the predetermined amount being less than an amount of drawing of the webbing necessary for restricting a passenger seated in the seat, the control system further being configured to judge that the webbing cannot be wound only by the winding spring when the actual amount of drawing of the webbing is less than the predetermined amount and to activate the motor to wind up the webbing during the non-fastened seat belt state when the two following conditions are simultaneously met:
that the actual amount of drawing of the webbing is less than the predetermined amount; andthat the-spindle has stopped moving. |
