Inflatable seat belt apparatus

An inflatable seat belt apparatus, comprising:

• a webbing, at least part of a portion which comes into contact with a passenger is formed into a bag-shape, wherein the webbing is maintained in a belt-shape form during initial conditions and the bag-shape portion is inflated by gas from gas generating means at the time of vehicle collision;
• a tongue provided on said webbing which is insertable into and lockable with a buckle to make possible restraint of the passenger;
• an intermediate guide, which has a through-hole through which the webbing is passed, for guiding said webbing through the through-hole in a freely movable manner;
• a through-hole opening-area control member movably provided on said intermediate guide and being movable between an opening-area reducing position and an opening-area enlarging position, said control member being held at said opening-area reducing position under initial conditions and being moved to said opening-area enlarging position in the event of a vehicle collision;
• wherein when said control member is at said opening-area reducing position, an opening area of the through-hole is defined at least in part by said control member to be a first size which allows movement of said webbing therethrough while said webbing is maintained in the belt-shape form, but which will impede turning over and twisting of said webbing, and when said control member is at said opening-area enlarging position, said opening-area of the through-hole is defined at least in part by said control member to be a second size which is larger than said first size and which is sufficient to allow gas to readily penetrate the bag-shape portion;
• and
• said control member remaining in said opening-area reducing position even during movement of said webbing through said through-hole and moving to said opening-area enlarging position when said bag-shape portion is inflated with gas from the gas generating means.