Seatbelt webbing lock preventing apparatus
The invention is related to a seatbelt webbing lock preventing apparatus enables a flywheel constituted as an inertia mass means to prevent a rotating lock of a lock mechanism followed by the webbing acceleration and deceleration of a seatbelt in any case of withdrawing the seatbelt from a retractor and rewinding it therein. The webbing lock preventing apparatus comprises a webbing control portion 10 including a locking portion with a torsion bar mechanism for limiting a force applied to a seatbelt, a locking actuation mechanism provided with a flywheel for controlling the operating of the locking portion and stopping the rotating of a spool and the webbing of the seatbelt in accordance with the webbing acceleration and deceleration of the seatbelt caused by withdrawing the seatbelt from the retractor and rewinding it thereinto; and a flywheel rotating control portion including a friction spring mounted in a hub of the locking actuation mechanism, thereby preventing the flywheel from being rotated with its inertia force at the time of the acceleration or deceleration of the webbing.
1. A seat belt webbing lock preventing apparatus of a seatbelt retractor, said seatbelt retractor comprising a spool and a webbing disposed about the spool, said seat belt webbing lock preventing apparatus comprising;
a webbing control portion comprising a locking portion and a locking actuation mechanism for operating the locking portion;
said locking portion comprising a torsion bar mechanism for limiting a force applied to a seatbelt, a locking base coupled to the torsion bar, and a pawl disposed on the locking base;
said locking actuation mechanism comprising a lock gear, a pawl spring compressively mounted between the locking base and the lock gear; a flywheel pivotally mounted onto the lock gear; a flywheel compressive spring biasing the flywheel relative to the lock gear; and
a flywheel rotation control portion comprising a retainer and a friction spring mounted on the retainer and engaging the flywheel to reduce movement of the flywheel at below a certain value of an acceleration or deceleration in response to withdrawal or rewinding of the webbing.
2. The seatbelt webbing lock preventing apparatus as claimed in claim 1 , in which;
the friction spring comprises a coupling portion; and
the retainer includes a ring portion comprising a ring portion having an inner tooth portion, and a supporting portion disposed within the ring portion and engaging the coupling portion.
3. The seatbelt webbing lock preventing apparatus as claimed in claim 2 , in which;
the coupling portion is in the form of a symbol Ω of Ohm.
4. The seatbelt webbing lock preventing apparatus as claimed in claim 3 , in which;
the friction spring is a wire spring or a leaf spring.