Inflatable seatbelt system

Claim 1

An inflatable seatbelt system for a vehicle including at least: means for generating a gas when deceleration acting on the vehicle upon occurrence of an emergency situation, for example, a collision of the vehicle, exceeds first set deceleration; a webbing having a portion brought into contact with an occupant's body, at least a part of said contact portion being formed as a bag-shaped portion, said webbing being arranged such that when no gas is generated from said gas generating means, said webbing is maintained in the shape of a strap having a predetermined width, whereas, when a gas is generated from said gas generating means, said bag-shaped portion is inflated by the gas; a retractor operating such that when the deceleration on the vehicle is not higher than second set deceleration, which is lower than said first set deceleration, said retractor allows said webbing to be freely wound up and unwound, whereas, when the deceleration on the vehicle exceeds said second set deceleration, said retractor prevents unwinding of said webbing; a tongue connected to said webbing; and a buckle device with which said tongue is disengageably engaged; wherein said tongue has an engagement portion engageable with said buckle device and having a gas inlet port to which the gas generated by said gas generating means is introduced through said buckle device when said tongue is in engagement with said buckle device, an operating portion having a webbing receiving hole through which said webbing extends and used to engage and disengage said tongue in relation to said buckle device, a gas outlet portion formed with a width larger than a width of said bag-shaped portion and connected to said webbing and having a gas outlet port for said gas, and a gas flow hole providing communication between said gas inlet and outlet ports, and wherein said webbing is formed of a webbing base fabric made out of a woven fabric, said webbing base fabric having warp disposed in a longitudinal direction of the seatbelt and weft disposed in a lateral direction of the seatbelt, said weft being formed of spandex threads made of a material having a relatively low modulus of elasticity and stretchable in a rubber-like manner, for example, urethane, said weft being cut in a predetermined region including one end of said bag-shaped portion, the gas outlet portion of said tongue being inserted into said bag-shaped portion from the weft cut area so that a part of said bag-shaped portion is brought into close contact with said gas outlet portion by elastic force of the weft which is not cut, said webbing extending through said webbing receiving hole at a portion thereof which extends in a direction opposite to the direction of insertion of said gas outlet portion so that said gas outlet portion is prevented from slipping out of said bag-shaped portion by at least the portion of said webbing which lies in said webbing receiving hole.