Chair

Abstract

A chair is such that concave grooves recessed rearward and forward and oriented in an upward/downward direction are formed in front and rear surfaces of left and right side portions of a backrest, and portions of mounting members installed at both sides an optional member are engaged with the concave grooves to mount the optional member on the backrest.

1 . A chair, wherein concave grooves recessed rearward and forward and oriented in an upward/downward direction are formed in front and rear surfaces of left and right side portions of a backrest, and portions of mounting members installed at both sides of an optional member are engaged with the concave grooves to mount the optional member on the backrest. 
     
     
         2 . The chair according to  claim 1 , wherein the concave grooves formed in the front and the rear of both sides of the backrest are in alignment with each other in a forward/rearward direction so that horizontal cross-sections of both sides of the backrest have a substantially “H” shape. 
     
     
         3 . A chair, wherein concave grooves recessed rearward and oriented in an upward/downward direction are formed in a front surface of a backrest, and portions of mounting members installed at both sides of an optional member are engaged with the concave grooves to mount the optional member on the backrest. 
     
     
         4 . A chair, wherein concave grooves recessed forward and oriented in an upward/downward direction are formed in a rear surface of a backrest, and portions of mounting members installed at both sides of an optional member are engaged with the concave grooves to mount the optional member on the backrest. 
     
     
         5 . The chair according to  claim 1 , wherein any one of upper and lower ends of the concave grooves in the backrest is blocked by a blocking piece. 
     
     
         6 . The chair according to  claim 1 , wherein the backrest comprises a pair of left and right side rods and a back plate connecting the side rods and having a forward/rearward directional thickness smaller than that of both of the side rods, and the concave grooves are formed on both of the side rods. 
     
     
         7 . The chair according to  claim 1 , wherein at least one convex portion or at least one concave portion is formed in an inner surface of each of the concave grooves, and the portions of the mounting members are engaged with the convex portions or the concave portions. 
     
     
         8 . The chair according to  claim 1 , wherein a plurality of convex portions or concave portions are formed in the inner surfaces of the concave grooves at predetermined intervals in the upward/downward direction, and the portions of the mounting members are selectively engaged with the convex portions or the concave portions, so that the optional member is installed at the backrest in the upward/downward direction in a manner capable of adjusting a mounting position. 
     
     
         9 . The chair according to  claim 8 , wherein the mounting members of the optional member comprise surrounding pieces extending outward from side ends of the optional member and surrounding side ends of the backrest, elastic members installed at the surrounding pieces, and engaging claws installed at ends of any one of upper and lower front ends of the surrounding pieces and fitted to the concave grooves of the backrest to be selectively engaged with the plurality of convex portions or concave portions formed in the concave grooves, so that the optional member can be locked to the backrest at the plurality of heights, and wherein the engaging claws are biased by the elastic members in a direction of engaging the mounting members with the convex portions or the concave portions with respect to the backrest, so that the engaging claws can be separated from the convex portions or the concave portions by moving the optional member against the biasing force. 
     
     
         10 . The chair according to  claim 1 , wherein the mounting members of the optional member comprise surrounding pieces extending outward from side ends of the optional member and surrounding side ends of the backrest and elastic members installed at the surrounding pieces, at least one of the front ends of the surrounding pieces and the elastic members is engaged with the concave grooves of the backrest, and the side ends of the backrest are sandwiched by the front ends of the surrounding pieces and the elastic members. 
     
     
         11 . The chair according to  claim 1 , wherein the optional member is any one or a plurality of a hanger for hanging clothes, a headrest, an armrest, and a lumbar support.