Patent ID: 6843534
Filing Date: 2005-01-18
Classification: A47C

Abstract:
1. In a chair formed of a seat and backrest supported by support legs, an armrest apparatus installed in a chair for a computer work, comprising: an armrest body which is vertically fixedly installed at one side of a chair; an upper receiving space which is formed in an inner upper portion of the armrest body and is formed widely in front and rear sides in such a manner that the upper potion of the upper receiving space is opened; a lifting and lowering guide space which is formed in a lower portion of the upper receiving space of the armrest body and is formed in a vertical direction in such a manner that the lifting and lowering guide space communicates with the upper receiving space; a link body which is received in the upper receiving space of the armrest body or which is ejected therefrom based on a lifting operation; a lifting and lowering guide member in which an inner rod is movable in upward and downward directions in the interior of an outer rod and is installed in the lifting and lowering guide space of the armrest body and is liftable therein, and an upper end of the outer rod is rotatably engaged to a lower link of the link body, and a lower end of the outer rod is elastically supported by a main spring, and an upper end of the inner rod passes through an operation groove formed in the lower link of the link body in such a manner that the upper end of the inner rod is movable in upward and downward directions, and a circular ring is elastically supported by a subsidiary spring installed in the operation groove, for thereby guiding a receiving operation and ejection operation of the link body; a first link member which is installed in such a manner that the first link member is horizontally movable in a slide moving space formed between an upper link and the lower link of the link body; a first pin member which includes upper and lower ends which pass through a rear end portion of the first link member and are horizontally movably and rotatably installed in upper and lower guide grooves which are opposite to each other in lower and upper surfaces of the upper and lower links of the link body; a second link member which is installed in a front end portion of the first link member and in an upper portion of the upper link of the link body; a second pin member which rotatably connects a rotation end of the second link member and the front end portion of the first link member; and an armrest member which is rotatably connected with respect to a free end of the second pin member and is placed on an upper surface of the armrest body and is lifted for thereby opening and closing the upper receiving space and is used as an armrest on which an arm of a user is placed at a usual time and is upwardly lifted during a computer work and is freely movable on a horizontal surface.