| 摘要 |
<p>PROBLEM TO BE SOLVED: To rapidly and securely lock, if necessary, the rotation of a spool in the direction to unwind webbing, while also preventing a lock means from being actuated when the webbing is abruptly unwound. SOLUTION: At the occurrence of vehicle deceleration equal to or greater than a predetermined deceleration, the rotation of the spool 4 in the directionαto unwind the webbing is locked by a first lock means 5 using a solenoid 19, independently of the rotational movement of the spool 4. Then the rotation of the spool 4 in the directionαto unwind the webbing is rapidly locked and the amount of rotation of the spool 4 before actuation of the first lock means 5 decreases, reducing the amount by which the webbing 3 is unwound. If the solenoid 19 is not powered when necessary and the rotation of the spool 4 is not locked by the first lock means 5, then the electromagnet 34 is made to carry no current and a second lock means 6 locks the rotation of the spool 4 in the directionαto unwind the webbing. Thus, even if the first lock means 5 is not actuated, the rotation of the spool 4 in the directionαto unwind the webbing is securely locked.</p> |
