Airbag device
An airbag device equipped with an airbag having a reduced volume. An airbag inflated and expanded, by supplied gas, from a state folded in the rear of an instrument panel with respect to the vehicle's front-rear direction has an outer bag for restraining the upper body of a vehicle occupant from the front side in the vehicle's front-rear direction and also has a reaction force support tube inflated and expanded, by supplied gas, at the front on the inner side of the outer airbag. An inflator supplies gas to each of the outer bag and the reaction force support tube. When the outer bag restrains the upper body of the vehicle occupant, gas discharge from the reaction force support tube is suppressed by a one-way valve and the pressure in the reaction force support tube is maintained at a pressure higher than the pressure in the outer bag.
1. An airbag device comprising:
a first bag that receives a gas supply and is inflated and expanded from a folded-up state within a rear portion of an instrument panel in a vehicle longitudinal direction to thereby restrain a vehicle passenger from a front side in the vehicle longitudinal direction;
a second bag that: i) has a smaller volume than the first bag, ii) has a bag-body that is independent from the first bag, iii) receives the gas supply, and iv) is inflated and expanded from a folded-up state together with the first bag, in an interior of the first bag such that,
when the first bag restrains the vehicle passenger, an upper end side portion of the second bag extending in a vehicle vertical direction contacts a windshield glass and a lower end side portion of the second bag contacts a surface of the instrument panel;
an inflator that is configured to generate the gas supply to the first bag and the second bag;
an internal pressure difference imparting structure that includes a gas discharge suppressing structure that is configured to: i) suppress discharging of gas that has been supplied to the second bag, and ii) make an internal pressure of the second bag higher than an internal pressure of the first bag, at least when the first bag restrains the vehicle passenger; and
a gas flow path member that: i) is flexible, ii) is folded-up together with the first bag and the second bag, iii) is inflated and expanded by the gas supply from the inflator, and iv) directly supplies gas from the inflator to the first bag and the second bag respectively.
2. The airbag device of claim 1 , wherein the gas discharge suppressing structure includes a one-way valve that is disposed along the gas flow path member or along a communicating portion of the gas flow path member and the second bag, and that permits gas flow from the gas flow path member to the second bag and prevents or suppresses gas flow from the second bag to the gas flow path member.
3. The airbag device of claim 1 , wherein the second bag is configured to expand, within the first bag, into a shape which causes an interval between two edges of the second bag to gradually widen in a vehicle transverse direction, from a lower end toward an upper end in the vehicle vertical direction.
4. The airbag device of claim 1 , further comprising:
a third bag that: i) has a smaller volume than the first bag, ii) receives a gas supply through the gas flow path member, and iii) is inflated and expanded from a folded-up state, so as to contact the instrument panel at a lower side in the vehicle vertical direction with respect to the first bag at least when the first bag restrains the vehicle passenger; and
a gas discharge suppressing structure that is configured to suppress discharging of gas that has been supplied to the third bag.
5. The airbag device of claim 4 , wherein the third bag is inflated and expanded, to thereby restrain knees of the vehicle passenger from a rear side in the vehicle longitudinal direction.
6. An airbag device comprising:
a first bag that receives a gas supply and is inflated and expanded from a folded-up state within a rear portion of an instrument panel in a vehicle longitudinal direction, to thereby restrain a vehicle passenger from a front side in the vehicle longitudinal direction;
a pair of second bags that: i) are provided within the first bag, ii) have a smaller volume than the first bag, and iii) are configured to expand to thereby cause an interval between the pair of second bags in a vehicle transverse direction to gradually widen from a lower end toward an upper end in a vehicle vertical direction, iv) receive a gas supply, and v) are inflated and expanded from a folded-up state together with the first bag, in an interior of the first bag or at a front side of the first bag in the vehicle longitudinal direction with respect to the first bag such that,
when the first bag restrains the vehicle passenger, an upper end side portion of the pair of second bags extending in a vehicle vertical direction contacts a windshield glass and a lower end side portion of the pair of second bags contacts a surface of the instrument panel;
an inflator that is configured to generate the gas supply to the first bag and the pair of second bags;
an internal pressure difference imparting structure that includes a gas discharge suppressing structure that is configured to: i) suppress discharging of gas that has been supplied to the pair of second bags, and ii) make an internal pressure of the pair of second bags higher than an internal pressure of the first bag, at least when the first bag restrains the vehicle passenger; and
a gas flow path member that: i) is flexible, ii) is folded-up together with the first bag and the pair of second bags, iii) is inflated and expanded by the gas supply from the inflator, and iv) directly supplies gas from the inflator to the first bag and the pair of second bags, respectively.
7. The airbag device of claim 6 , wherein the gas discharge suppressing structure includes a one-way valve that is disposed along the gas flow path member or along a communicating portion of the gas flow path member and the pair of second bags, and that permits gas flow from the gas flow path member to the pair of second bags and prevents or suppresses gas flow from the pair of second bags to the gas flow path member.
8. The airbag device of claim 7 , further comprising:
a third bag that: i) has a smaller volume than the first bag, ii) receives a gas supply through the gas flow path member, and iii) is inflated and expanded from a folded-up state, so as to contact the instrument panel at a lower side in the vehicle vertical direction with respect to the first bag at least when the first bag restrains the vehicle passenger; and
a gas discharge suppressing structure that is configured to suppress discharging of gas that has been supplied to the third bag.
9. The airbag device of claim 8 , wherein the third bag is inflated and expanded, to thereby restrain knees of the vehicle passenger from a rear side in the vehicle longitudinal direction.