Vehicle seat

1. A vehicle seat comprising:

a seatback frame that includes a pair of an outer side frame portion and an inner side frame portion which are disposed to be spaced from each other in a seat width direction and are disposed near an inside and an outside of a vehicle width direction, and a lower frame portion extending in the seat width direction between lower areas of the outer side frame portion and the inner side frame portion;

a tilting shaft that supports the seatback frame at a position below the lower frame portion so as to be tiltable about a cushion frame or a vehicle body; and

a first load transfer block that protrudes outward in the vehicle width direction from an upper side of the outer side frame portion in the vehicle width direction and transfers an impact load input from a side portion of the vehicle body to the seatback frame, the first load transfer block being provided above the tilting shaft,

wherein the vehicle seat further comprises:

a plate-shaped rigid member of which an upper end is connected to the lower frame portion and an inner end in the vehicle width direction is connected to the inner side frame portion in the vehicle width direction; and

a plate-shaped reinforcement member of which an upper end is connected to the lower frame portion and a lower end is connected to a lower end of the plate-shaped rigid member,

wherein a lower edge of the plate-shaped rigid member extends downward to below the lower frame portion and below the tilting shaft, the plate-shaped rigid member and the plate-shaped reinforcement member form a closed cross-section extending in the vehicle width direction, the plate-shaped reinforcement member is disposed in front of the tilting shaft, and the plate-shaped rigid member is disposed in rear of the tilting shaft, and

wherein the lower frame portion is provided with a slope that is bent obliquely upward and toward the outer side frame portion in the vehicle width direction and the plate-shaped rigid member is connected to the lower frame portion so as to be along the slope.

2. The vehicle seat according to claim 1 , further comprising:

a second load transfer block that protrudes outward in the seat width direction from a position extending from the tilting shaft near the outer side frame portion in the vehicle width direction and transfers the impact load input from the side portion of the vehicle body to the seatback frame.

3. The vehicle seat according to claim 1 ,

wherein the plate-shaped rigid member is connected to the inner side frame portion in the vehicle width direction at a height position lower than the tilting shaft.

4. The vehicle seat according to claim 1 ,

wherein the tilting shaft is disposed inside the closed cross-section formed by the plate-shaped rigid member and the plate-shaped reinforcement member.

5. The vehicle seat according to claim 1 ,

wherein a distant space is provided between an inner end of the lower frame portion in the vehicle width direction and the inner side frame portion in the vehicle width direction, and a driving motor is disposed in the distant space so as to adjust a tilting angle of the seatback frame.

6. The vehicle seat according to claim 5 ,

wherein the plate-shaped rigid member connects the lower frame portion to the inner side frame portion in the vehicle width direction by bypassing an outside of the driving motor.

7. The vehicle seat according to claim 6 ,

wherein the plate-shaped rigid member extends from the lower frame portion to a height going around a lower side of the driving motor, and the inner end of the plate-shaped rigid member in the vehicle width direction is attached to the inner side frame portion in the vehicle width direction across a height area lower than the driving motor.

8. The vehicle seat according to claim 1 ,

wherein the lower frame portion, the plate-shaped reinforcement member, and the plate-shaped rigid member are disposed in a substantially same horizontal plane above the tilting shaft, and the plate-shaped rigid member and the lower frame portion are connected above the tilting shaft.

9. The vehicle seat according to claim 1 ,

wherein the lower frame is formed by a pipe material, extends to the first load transfer block, and obliquely transfers the impact load input from the side portion of the vehicle body through the first load transfer block.