Seat belt webbing lock apparatus and assembly therefor

A webbing lock apparatus for use in a vehicle seat belt system, said apparatus comprising:

• a shaft rotatably mounted to a spool frame;
• a spool interlocked with said shaft for rotation therewith, said spool having an intermediate portion for winding thereon, and unwinding therefrom, a seat belt webbing;
• a ratchet wheel interlocked with said shaft for rotation therewith;
• a hook retainer interlocked with said shaft for rotation therewith;
• a lock ring raced on said shaft adjacent said hook retainer, said lock ring having a ratchet portion;
• a hook movably mounted on said hook retainer for selective locking engagement with said ratchet portion of said lock ring;
• a spring connected between said hook and said hook retainer serving to directly elastically bias said hook out of engagement with said ratchet portion, said spring comprising a coil mounted on an axial boss of said hook retainer, and a pair of arms engaged, respectively, with said hook retainer and said hook for providing a continuous biasing force on said hook;
• a flywheel assembly raced with respect to said shaft and being coupled with said hook for moving said hook into engagement with said ratchet portion, against the bias of said spring, upon relative movement of said flywheel assembly and said hook retainer, whereby said lock ring is temporarily coupled for rotation with said shaft;
• a pawl coupled to said lock ring such that rotation of said lock ring with said shaft causes said pawl to lockingly engage said ratchet wheel, to thereby temporarily inhibit unwinding of said web;
• and
• a plurality of spaced lock members provided on said hook retainer, an arm of said spring being selectively engageable with said lock members in order to vary the spring force biasing the hook out of engagement with said ratchet portion.