The armrest support structure is capable of ensuring an appearance quality on the upper side of a hinge cover and capable of making it less likely for a garment or the like to be caught on said upper side. A reverse flange protruding upward from an upper part of a hinge cover is inserted into an opening and extends along a reverse side of a front surface of a skin material, whereby the reverse flange can restrict recession of the skin material on the upper side of the hinge cover. Therefore, an appearance quality on the upper side of the hinge cover can be ensured, and it can be made less likely for a garment or the like to be caught between the upper side of the hinge cover and the skin material.

An extendible armrest for a seat structure includes a pivot plate configured to be fixed to the seat structure and having a pivot hole and a first curved pivot slot and a second curved pivot slot. An extension plate includes a pivot pin pivotally connecting the extension plate to the pivot plate and including a guide pin supported by the extension plate and received in the first curved pivot slot. The extension plate further includes a guide slot. An armrest supports a first guide pin received in the second curved pivot slot of the pivot plate and supporting a second guide pin received in the guide slot of the extension plate. The armrest assembly permits a folding type armrest that allows the armrest to move forward when unfolded so that the entire armrest surface can be utilized.

To provide an armrest that enables suppression of deterioration of the mountability of an accommodation member to a frame and that can make it less likely for the accommodation member to be detached from the frame. A claw of a second engaging portion and a second to-be-engaged portion are opposed to each other in a first direction (the direction of arrows U-D) over an overlap length in a state where an extending portion of the second engaging portion has been brought into contact with an outer peripheral surface of a body portion by elastically deforming the extending portion about a base side from a state where the claw is hooked on the second to-be-engaged portion.

An armrest assembly for a vehicle seat includes an armrest body and a first shaft that extends from a first side of the armrest body along an armrest axis and is attached to the armrest body for relative rotational movement about the armrest axis. The armrest assembly also includes a second shaft that extends from a second side of the armrest body along the armrest axis and is attached to the armrest body for relative rotational movement about the armrest axis. A detent body is fixed on the first shaft and includes a first detent and a second a second detent. A stop is fixed on the armrest body. The stop is retained in the first detent when the armrest body is in a first position relative to the first shaft. The stop is retained in the second detent when the armrest body is in a second position relative to the first shaft.