Airbag device

1. An airbag device, the airbag device comprising:

an airbag for protecting an occupant seated in a seat of a vehicle; and

an inflator for injecting gas to deploy the airbag;

wherein:

the airbag in an expansion completed state where expansion and deployment are complete includes:

a first cushion configured to cover at least a side of a head of the occupant; and

a second cushion connected to a back of the first cushion, and extending downward from a connecting point between the first cushion and the second cushion; and

a notched section extending from a front towards a back between the first cushion and the second cushion, and

wherein the airbag in the expansion completed state further comprises a duct section positioned at the back of the notched section that enables communication between the first cushion and the second cushion, the duct section connected to a stowing section of the inflator.

2. The airbag device according to claim 1 , wherein of the first cushion, a side of head protecting section that protects the side of the head of the occupant has a plurality of non-expandable sections arranged surrounding an expansion region that is expanded by gas from the inflator in addition to regions close to connecting parts with the duct sections.

3. The airbag device according to claim 2 , wherein the non-expandable sections of the plurality of non-expandable sections are arranged at intervals on the side of head protecting section in the expansion completed state on a virtual straight line extending from the back to the front.

4. The airbag device according to claim 2 , wherein the non-expandable sections of the plurality of non-expandable sections are lined up on the side of head protecting section in the expansion completed state on a virtual straight line extending from a lower side to an upper side.

5. The airbag device according to claim 1 , wherein the first cushion in the expansion completed state further includes a front protecting section configured to cover the front of the head of the occupant formed continuous to the front of the side of head protecting section in addition to the side of head protecting section for protecting the side of the head of the occupant.

6. The airbag device according to claim 5 , wherein a region to the side of head protecting section side of the front protecting section is a continuous expansion region from an upper end to a lower end.

7. The airbag device according to claim 6 , wherein a front side non-expandable section extends vertically near a center in a left-right direction of the front protecting section.

8. The airbag device according to claim 1 , wherein the duct section has a first communication port to the first cushion and a second communication port to the second cushion and with the airbag in a non-expanded and spread out state, a minimum width of the second communication port is larger as compared to a minimum width of the first communication port.

9. The airbag device according to claim 1 , wherein relative to the first cushion for protecting the side of the head of the occupant, a plurality of cushions are connected for circumferentially covering a front of the head and a side of the head on an opposite side.

10. The airbag device according to claim 1 , wherein with the first cushion and the second cushion in a state of being spread out flat and in an expansion completed state, an angle between an outer periphery of the first cushion and that outer periphery of the second cushion that form the notched section is an obtuse angle.

11. An airbag device, the airbag device comprising:

an airbag for protecting an occupant seated in a seat of a vehicle; and

an inflator for injecting gas to deploy the airbag;

wherein:

the airbag in an expansion completed state where expansion and deployment are complete includes:

a first cushion configured to cover at least a side of a head of the occupant; and

a second cushion connected to a back of the first cushion, and extending downward from a connecting point between the first cushion and the second cushion; and

a notched section extending from a front towards a back between the first cushion and the second cushion, and

wherein the first cushion in the expansion completed state further includes a front protecting section that covers the front of the head of the occupant formed continuous to the front of the side of head protecting section in addition to the side of head protecting section that protects the side of the head of the occupant.

12. An airbag device, the airbag device comprising:

an airbag for protecting an occupant seated in a seat of a vehicle; and

an inflator for injecting gas to deploy the airbag;

wherein:

the airbag in an expansion completed state where expansion and deployment are complete includes:

a first cushion configured to cover at least a side of a head of the occupant; and

a second cushion connected to a back of the first cushion, and extending downward from a connecting point between the first cushion and the second cushion; and

a notched section extending from a front towards a back between the first cushion and the second cushion, and

wherein relative to the first cushion for protecting the side of the head of the occupant, a plurality of cushions are connected for circumferentially covering a front of the head and a side of the head on an opposite side.