1. Field of the Invention
The present invention relates to a head protecting airbag system that deploys an airbag downward along the side of a vehicle body in a passenger compartment when the vehicle is involved in either a side collision or a rollover. In particular, the present invention relates to a head protecting airbag system that deploys an inflation section between an occupant's head and the vehicle body.
2. Description of the Related Art
In the recent trends, a head protecting airbag system is mounted in vehicles as a supplemental restraint system. The head protection airbag system has a curtain airbag that is deployed downward from a roof side rail when the vehicle is involved in a side collision or rollover. As one of such head protecting airbag systems, there has been proposed a head protecting airbag system designed to deploy the airbag between the head of the occupant and the side of the vehicle body in order to protect the occupant's head.
This type of head protecting airbag system is described in Japanese Patent Application Publication No. 2004-58848 (JP-A-2004-58848). In this head protecting airbag system, the airbag includes a gas supply path and a main inflation part disposed on the lower side of the gas supply path. The airbag is folded with the main inflation part rolled up toward the outer side in the vehicle and with the gas supply path not rolled, but folded for the sake of easier deployment of the airbag upon gas supply. In addition, in Japanese Patent Publication No. 3656156, at the initial stage of deployment of the airbag, a part of the airbag deploys into a thin plate shape between the pillar and the headrest of the occupant seat with no gas supplied. Then, gas is supplied into the thin plate airbag from an inflow port formed on the lower side of the airbag. This prevents the inflating airbag from being interfered with by the headrest of the occupant seat.
However, in order to immediately deploy the airbag in the longitudinal direction of the vehicle along the side of the passenger compartment, the airbag has to initially deploy inward towards the passenger compartment over the top end of the pillar garnish.