Vehicle seat

A vehicle seat comprising:

• a seatback;
• a back frame forming a framework of the seatback;
• and
• an armrest configured to be pivotable between a stored position in which the armrest is stored in the seatback and an in-use position in which the armrest is folded down toward a front side of the seat,
• wherein the armrest comprises:
• two side frames disposed so as to be spaced apart in a seat width direction;
• and
• a stopper pin projecting outside from the two side frames in the seat width direction,
• wherein the back frame comprises two support brackets to which the two side frames are respectively pivotably coupled,
• wherein the two support brackets respectively comprise guide slots in which the stopper pin is inserted, the guide slots being configured to guide the stopper pin when the armrest pivots, and
• wherein, on a reference surface that is perpendicular to the seat width direction and defined for each of the two side frames, a locus of one of the guide slots of a corresponding one of the two support brackets is projected, and a shape of a corresponding one of the two side frames and a shape of a portion of the stopper pin inserted into the guide slots are also projected on the reference surface,
• wherein the locus, as projected on the reference surface, is delineated by the guide slots moving relative to the two side frames when the armrest pivots, and a diameter of a largest perfect circle that can be fitted into nonoverlapping areas of the locus that do not overlap with the corresponding one of the two side frames or the stopper pin is smaller than a width of the one of the guide slots, and
• at least one of the two side frames comprises:
• a panel shaped main body;
• and an auxiliary bracket attached to the main body, and wherein the auxiliary bracket is plate shaped and is a separate member from the main body.