Patent ID: 6533355
Filing Date: 2003-03-18
Classification: A47C,Y10T

Abstract:
A chair comprising:a seat assembly for supporting a user thereon; an upright supported on the seat assembly which projects upwardly; a body supporting chair component which is movably supported on said upright to permit adjustment of the height of the chair component between upper and lower limits of vertical travel; and a height adjustment mechanism connecting said chair component and said upright together, said height adjustment mechanism including a gear assembly on one of said upright and said chair component and a rack member supported on the other of said upright and said chair component, said rack member including a vertically elongate rack defined by a plurality of rack teeth, and said gear assembly having a gear housing and a gear which is rotatably supported on said gear housing, said gear having gear teeth which extend about a circumference of said gear and continuously mesh with said rack teeth during raising and lowering of said chair component between said upper and lower limits of travel wherein said gear rotates in response to relative vertical movement between said rack and said gear assembly, said gear assembly further including a locking member which is engagable with said gear to prevent rotation thereof wherein said gear and said locking member are movable away from each other out of engagement during raising of said chair component to permit rotation of said gear and movable toward each other into engagement to prevent rotation of said gear which prevents lowering of said chair component by said meshing of said gear teeth and said rack teeth, said gear assembly further including a disengagement member which is movable between an operative position which maintains said gear and said locking member separated to permit lowering of said chair component and an inoperative position to permit said gear and said locking member to move toward and away from each other during raising of said chair component.