Abstract: An armrest according to the present invention includes a support member (8a, 215, 308a) which is a support structure, and an armrest main body (8b, 216, 308b), the armrest main body (8b, 216, 308b) includes a lower layer member (8j) including an operation lever (8p, 235, 308p) which is supported by a support member (8a, 215, 308a) to be movable in a forward-and-rearward direction and is operated by a seated person, and an upper layer member (8k) supported by the lower layer member (8j) to be movable in right-and-left direction, and the upper layer member (8k) covers the operation lever (8p, 235, 308p) at a base position in the right-and-left direction.

Abstract: An armrest according to the present invention includes a support member (8a, 215, 308a) which is a support structure, and an armrest main body (8b, 216, 308b), the armrest main body (8b, 216, 308b) includes a lower layer member (8j) including an operation lever (8p, 235, 308p) which is supported by a support member (8a, 215, 308a) to be movable in a forward-and-rearward direction and is operated by a seated person, and an upper layer member (8k) supported by the lower layer member (8j) to be movable in right-and-left direction, and the upper layer member (8k) covers the operation lever (8p, 235, 308p) at a base position in the right-and-left direction.

Abstract: In a chair (1) and a backrest (30) for the chair of the invention, thin back plate extension parts (51) that are continuous with a front surface of a back plate part (31), thinned sections being formed in outside portions, in a width direction of the backrest, on the rear surface side; and reinforcing ribs (52) that protrude from inside end parts of the back plate extension parts (51) in the width direction of the backrest to a rear side are provided in regions of side edge support parts (32) above parts where fitting holes (33) are formed. The reinforcing ribs (52) extend substantially in an upward-downward direction, gradually increase in cross-sectional area on a bottom end side, are connected to the parts where the fitting holes (33) are formed.

Abstract: In a chair (1) and a backrest (30) for the chair of the invention, thin back plate extension parts (51) that are continuous with a front surface of a back plate part (31), thinned sections being formed in outside portions, in a width direction of the backrest, on the rear surface side; and reinforcing ribs (52) that protrude from inside end parts of the back plate extension parts (51) in the width direction of the backrest to a rear side are provided in regions of side edge support parts (32) above parts where fitting holes (33) are formed. The reinforcing ribs (52) extend substantially in an upward-downward direction, gradually increase in cross-sectional area on a bottom end side, are connected to the parts where the fitting holes (33) are formed.

Abstract: An armrest device for a chair includes a lower support rod that rises at a side of a chair seat and has a tubular upper end portion; and an upper support cylinder that has an armrest provided in an upper end thereof, is externally fitted to the lower support rod so as to be slidable in an up-down direction, and has a plurality of engaging portions therein. The armrest is made height-adjustable with respect to the lower support rod by disposing the locking member and a biasing member at an upper end portion of the lower support rod and providing the rotating rod inside the lower support rod.

Abstract: A load-supporting body includes a base plate constituting a framework; a cushion material arranged on a front surface side of the base plate; an upholstery material stretched to cover an outside surface of the cushion material and an outer peripheral edge of the base plate; and a tightening cord inserted through a peripheral edge of the upholstery material and tightened to allow end parts to be tied together on a rear surface side of the base plate in a state in which the upholstery material has covered the outside surface of the cushion material and the outer peripheral edge of the base plate. The base plate is provided with a first side wall and a first protruding wall that restricts displacement of the tightening cord in a base-plate center direction, and a second side wall and a second protruding wall that restrict displacement of the tightening cord in a base plate outward direction.

Abstract: An armrest device for a chair includes a lower support rod that rises at a side of a chair seat and has a tubular upper end portion; and an upper support cylinder that has an armrest provided in an upper end thereof, is externally fitted to the lower support rod so as to be slidable in an up-down direction, and has a plurality of engaging portions therein. The armrest is made height-adjustable with respect to the lower support rod by disposing the locking member and a biasing member at an upper end portion of the lower support rod and providing the rotating rod inside the lower support rod.