Patent ID: 8251453

Claim:
An adjustable armrest support of a chair; comprising: a lower pillar for being connected to a cushion of the chair, comprising: a positioning board, having a longitudinal positioning slot, wherein the positioning slot comprises a straight through hole and a plurality of semicircular holes arranged in a row and communicating with the straight through hole; a linking board, being of an inverted-L shape, having a horizontal top, an inclined hole and a handle being mounted on the top; a T-shaped frame composed of a vertical portion and a horizontal portion, the horizontal portion being provided with a transversal limiting hole positionally corresponding to the positioning slot and the inclined hole, and the hole, the positioning slot and the inclined hole being penetrated through by a bolt; a compression spring disposed between the horizontal portion of the T-shaped frame and the top of the linking board for exerting a downward force on the linking board; and a main body having a hollow portion and a trough communicating therewith, the positioning board, the T-shaped frame and the linking board being accommodated in the hollow portion through the trough, and the positioning board is sandwiched between the T-shaped frame and the linking board; and an upper pillar for connecting an armrest, being hollow to slidably accommodate the lower pillar, one side of the upper pillar being provided with a through hole corresponding to the top of the linking board for allowing the top of the linking board to pass through and to be movable therein; wherein the positioning board is fastened with the main body, the horizontal portion of the T-shaped frame is fastened atop the upper pillar; when the handle is not forced, the linking board is pushed by the compression spring to move downwards, and the bolt moves to an upper end of the inclined hole and enters a semicircular hole to form a position effect; when the handle is pulled up, the bolt moves to a lower end of the inclined hole and enters the straight through hole to form an adjustable effect.