Vertically height adjustable seatback for a vehicle

A vehicle comprising:

• a body defining, at least in part, a passenger compartment;
• and
• a seat arranged in the passenger compartment, the seat comprising:
• a seat base, the seat base comprising a pair of side walls;
• and
• a seatback coupled to the seat base,
• a first frame member and a second frame member that are spaced apart from each other and coupled to the seat base between the side walls of the seat base;
• an adjustment mechanism comprising a shaft extending along a lateral axis between the first frame member and the second frame member and rotatably mounted on the first frame member and the second frame member so as to be rotatable about the lateral axis but fixed linearly with respect to the first frame member and the second frame member, a first adjustor mounted on the shaft and rotatable therewith, the first adjustor comprising a first plurality of gear teeth, and a second adjustor mounted on the shaft and rotatable therewith, the second adjustor comprising a second plurality of gear teeth;
• a third frame member coupled to the first frame, member via the first adjustor and comprising a first outwardly facing surface that is parallel to the lateral axis and that comprises a first plurality of openings, the first plurality of gear teeth of the first adjustor engageable with the first plurality of openings such that, when the first adjustor is rotated about the lateral axis, the third frame member is moved linearly with respect to the first frame member;
• and
• a fourth frame member coupled to the second frame member via the second adjustor and comprising a second outwardly facing surface that is parallel to the lateral axis and that comprises a second plurality of openings, the second plurality of gear teeth of the second adjustor engageable with the second plurality of openings such that, when the second adjustor is rotated about the lateral axis, the fourth frame member is moved linearly with respect to the second frame member,
• wherein the seatback is fixed to the third and fourth frame members so as to be linearly movable relative to the seat base,
• wherein the seatback comprises a forward surface structured as a back support portion and a rear surface opposite the forward surface, and a pair of side surfaces extending between the forward surface and the rear surface, and
• wherein the third and fourth frame members are disposed entirely within a space defined by the forward surface, the rearward surface, and the side surfaces.