Vehicle seat

1. A vehicle seat comprising:

a seat frame that includes a plurality of frame members joined to each other at a plurality of connection points in which a stress concentration occurs in the seat frame during a vehicle collision, the connection points being regions where joined frame members make surface contact with each other; and

a reinforcing member that is attached to at least one of the plurality of joined frame members such that the reinforcing member extends across and overlaps at least one connection point of at least one set of joined frame members of the plurality of joined frame members to disperse a stress from the stress concentration that occurs at the at least one connection point during the vehicle collision, and

the reinforcing member having a specific gravity smaller than a specific gravity of the seat frame.

2. The vehicle seat according to claim 1 , wherein

the reinforcing member is a unidirectional tape.

3. A vehicle seat comprising:

a seat frame including at least two frame members joined to each other at at least two connection points in which a stress concentration occurs in the seat frame during a vehicle collision, the connection points being regions where the at least two joined frame members make surface contact with each other; and

a reinforcing member that extends across and overlaps at least one of the at least two connection points of the at least two joined frame members to disperse a stress from the stress concentration that occurs at the at least two connection points during the vehicle collision, and the reinforcing member having a specific gravity smaller than a specific gravity of the seat frame, wherein

the reinforcing member is attached to at least one of a side surface of one of the at least two frame members on an outer peripheral side of the one of the at least two frame members in a direction extending across the at least one of the at least two connection points in which a maximum tensile stress is generated at a time when a load causing bending in a direction perpendicular to a longitudinal direction in which the seat frame extends is applied to the seat frame, and a side surface of the one of the at least two frame members on an inner peripheral side of the one of the at least two frame members in the direction extending across the at least one of the at least two connection points in which a maximum compression stress is generated at the time when the load is applied to the seat frame,

the reinforcing member being attached to the at least one of the outer peripheral side and the inner peripheral side of the one of the at least two frame members in a state in which the reinforcing member receives the load and disperses a corresponding one of the maximum tensile stress and the maximum compression stress.

4. The vehicle seat according to claim 3 , wherein

the reinforcing member is a unidirectional tape.

5. A vehicle seat comprising:

a seat frame including at least two frame members joined to each other at a connection point in which a stress concentration occurs in the seat frame during a vehicle collision, the connection point being a region where the at least two joined frame members make surface contact with each other; and

a reinforcing member that extends across and overlaps the connection point of the at least two joined frame members to disperse a stress from the stress concentration that occurs at the connection point during the vehicle collision, and the reinforcing member having a specific gravity smaller than a specific gravity of the seat frame, wherein

the reinforcing member is provided on one of the at least two frame members in a direction extending across the connection point in which the stress concentration occurs such that the reinforcing member extends along a specific in-plane direction, and at least one of a size and a shape of the reinforcing member is changed in accordance with a magnitude of the stress.

6. The vehicle seat according to claim 5 , wherein

the reinforcing member is a unidirectional tape.