Seat

1. A seat comprising:

a backrest configured to support a back of a seated occupant;

a headrest provided to an upper portion of the backrest and configured to support a back of a head of the seated occupant;

an overhang portion configured to overhang forward so as to laterally cover the head of the seated occupant from a side portion of the headrest;

an overhang adjustment mechanism configured to adjust an overhang amount of the overhang portion; and

a height adjustment mechanism configured to adjust a height position of the headrest with respect to the backrest, wherein

the overhang portion further includes an air outlet configured to blow out air inward in a seat width direction.

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

a backrest angle adjustment mechanism configured to adjust a backrest angle of the backrest.

3. The seat according to claim 1 , further comprising:

a duct that allows air to flow in a flow path through the backrest, the duct being inserted into the headrest such that the flow path is overlapped with the headrest,

wherein the height adjustment mechanism is provided inside the headrest.

4. The seat according to claim 1 ,

wherein the overhang portion is provided to both side portions of the headrest.

5. The seat according to claim 4 ,

wherein the overhang adjustment mechanism has a structure configured to individually operate each overhang portion.

6. The seat according to claim 1 ,

wherein the height adjustment mechanism includes:

a headrest stay;

a fixed body fixed to an upper portion of the headrest stay; and

a movable body fitted to a lower portion of the headrest stay and slidable in a height direction with respect to the fixed body,

wherein the headrest is mounted to the movable body, and

wherein the height adjustment mechanism is configured to adjust the height position of the headrest with respect to the fixed body.

7. The seat according to claim 1 ,

wherein the overhang portion is configured to overhang forward so as to laterally cover an entirety of the head of the seated occupant from the side portion of the headrest.

8. The seat according to claim 1 ,

wherein when the backrest is moved from a first position in which the overhang portion covers the head of the seated occupant from the side portion of the headrest to a second position in which the overhang portion is disposed without covering an exposed portion of the head of the seated occupant from the side portion of the headrest, the height adjustment mechanism adjusts the height position of the headrest so that the overhang portion covers the exposed portion of the head of the seated occupant from the side portion of the headrest.