Emergency locking seat belt retractor

摘要

An emergency locking seatbelt retractor. The retractor includes a pivoting lock plate which can pivot through a limited arc during activation of a webbing sensor or a vehicle sensor. When the lock plate is in its quiescent position, a pin thereon operates to hold a lock bar out of engagement with ratchet teeth on the webbing spool, thereby allowing free rotation of the spool. If either or both of the webbing sensor and vehicle sensor are activated, the lock plate is caused to pivot, drawing the pin away from the lock bar and allowing the lock bar to engage the ratchet teeth, thereby locking the retractor. Additionally, the locking initiation mechanism (the lock plate) and the sensors are isolated from webbing withdrawal forces and may therefore be constructed of lightweight, inexpensive materials. The retractor includes a vehicle sensor which is effective in substantially eliminating any vertical motion of the sensor ball. This prevents the retractor from locking when it is subjected to a downward acceleration.