A seating posture is stabilized for the shoulders of a passenger seated on a vehicle seat. A vehicle seat is provided with a seat back configured to support the seated person from the rear. A shoulder support portion of the seat back configured to support a corresponding one of the shoulders of the seated passenger includes an air cell configured to expand when air is supplied. When the air cell expands, one end portion of the shoulder support portion on the outside in the width direction of the vehicle seat moves more forward than the other end portion of the shoulder support portion on the inside in the width direction.

A method of assembling a vehicle seat is provided, comprising: providing a seat back frame; forwardly movably connecting a headrest for supporting a head of a seat occupant to the seat back frame; mounting a rear-end collision detector to the seat back frame at a position behind the seat occupant, operatively connecting the rear-end collision detector to the headrest; disposing a link member at a position lateral to the rear-end collision detector; forming a front extending portion that inwardly extends in a right-to-left direction at a front end of a lateral face of the side frame; and forming a rear extending portion that inwardly extends in the right-to-left direction; wherein a protruding portion is formed from a portion of the lateral face of the side frame that faces at least the part of the bracket, the link support shaft being disposed at a same height as the protruding portion.

A seat device includes a seatback frame attached to a seat cushion frame via a seatback attachment member. The seatback attachment member includes a first attachment point to which the seat cushion frame extending forward is attached, a second attachment point to which the rear portion of the seat cushion frame is attached, and a third attachment point to which the lower portion of the seatback frame is rotatably attached. The second attachment point has a floating structure.

A deformation element for a motor vehicle seat, which element is intended to be arranged on a subassembly of a motor vehicle seat, having a base member, a deformation portion which is formed on the base member and on which the deformation element can be deformed and/or destroyed under the action of an external force, and a force introduction region by means of which a structural element of a motor vehicle seat can be brought into operational connection with the deformation portion so that a force acting on that structural element can be introduced via the force introduction region into the deformation portion. The deformation portion is formed by means of partial deformation of the material of the deformation element and at the transition of the deformation portion to the base member of the deformation element there is a weakening region which defines at least one tear line.

In a structure in which a lower arm is fixed to a vehicle, provided is a vehicle seat that can reduce an impact applied to a recliner. One aspect of the present disclosure is a vehicle seat including a lower arm and a recliner. The lower arm includes an arm body to which the recliner is attached, a first fixing portion to be attached to the vehicle in a lower position, and a second fixing portion attached to the vehicle in a rear position. The arm body includes a first recess arranged between the recliner and the first fixing portion in an up-down direction, the first recess extending from an edge of the arm body, and a second recess arranged between the recliner and the second fixing portion in a front-rear direction, the second recess extending from the edge of the arm body.

A seat backrest includes right and left side frame segments, a pressure receiving member disposed between the side frame segments movably in a front-back direction, and a cushion pad covering the front of the side frame segments and pressure receiving member. The pressure receiving member includes a main body part, and extending parts extending laterally from both sides of the main body part. The cushion pad includes a back receiving part covering the front of the main body part, and bank parts disposed on both sides of the back receiving part, protruding forward from both sides, and covering the front of the extending parts and side frame segments. A recess is formed at an area, facing a corresponding extending part of the extending parts, of a rear surface of each bank part.

A vehicle seat includes a seat back, and an airbag that deploys in the seat back. After having deployed, the airbag has such a shape that a deployment amount, in a front-back direction, of the airbag near an upper part of the seat back differs from that near a lower part of the seat back. The airbag deploys in the seat back in such a way that, after having deployed, the airbag elastically supports an upper body of an occupant and elastically receives an impact force applied to a back surface of the seat back.

In order to improve steering operation operability during cornering while maintaining a driver holding property, a seat apparatus is provided with: a seat back frame; a cornering sensor for detecting a cornering direction of a vehicle; and a control unit that controls the seat back frame on the basis of the result of detection by the cornering sensor. The seat back frame is provided with: left and right side frames disposed on both sides of the seat back frame; a back plate disposed between the left and right side frames; and a swinging mechanism for swinging the back plate with respect to the direction of movement of the vehicle. The control unit controls the swinging mechanism such that, upon detection of a cornering direction of the vehicle by the cornering sensor, the inner one of the sides of the back plate with respect to the cornering direction is positioned rearward of the outer one of the sides with respect to the cornering direction.

The object of the invention is to provide a vehicle seat which can improve degree of freedom in the design of the vehicle seat. A vehicle seat with a seat cushion and a seat back includes: right and left side frames 20 constituting right and left frames of the seat back; a pressure-receiving member 40 disposed between the right and left side frames 20 and configured to receive a load from an occupant; and a driving mechanism 50 disposed at each of right and left sides of the pressure-receiving member 40 and configured to cause a right end portion or a left end portion of the pressure-receiving member 40 to move from an initial position to an advanced position that is located frontward of the initial position or to move from the advanced position to the initial position, wherein the driving mechanism 50 includes a linkage (drive link member 100 and contact link member 200) configured to be connected to the pressure-receiving member 40 and a driving source 52 configured to actuate the linkage, and wherein the linkage is configured to operate when a load equal to or greater than a predetermined amount is input from the occupant to the pressure-receiving member 40 to cause the pressure-receiving member 40 to move to a backward position that is located rearward of the initial position.

A back frame attachment structure, wherein a hack frame includes a pair of side frames, wherein a lower end portion side of the side frame is attached to an upper portion of a lower arm member whose lower portion is fixed to a vehicle body side member, wherein the lower arm member includes two plate-like members superimposed with each other in a seat width direction, the upper portion and the lower portion being connected to each other by a front connection portion and a rear connection portion which are separated by a through-hole, and wherein, when a large load is applied to the back frame, the two plate-like members are configured to absorb energy by being deformed to be separated from each other in the seat width direction by a compressive load in an upper and lower direction generated in the front connection portion or the rear connection portion.