Abstract: The present claimed invention intends to provide a chair having a frame structure that is effective for securing a required strength without needless structure to reinforce the strength. The chair has a chair body A comprising a seat frame 12, a back frame 22 and a rib that reinforces between the seat frame 12 and the back frame 22, wherein the rib is formed to extend to a side direction so as to be used as an arm frame 71, and the seat frame 12, the back frame 22 and the arm frame 71 are continuously and integrally formed three-dimensionally, and openings 12a, 22a into which a mesh member 13, 23 to form a seating face is fitted are arranged at the seat frame 12 and the back frame 22 respectively.

Abstract: The present claimed invention intends to newly provide a convenient chair that is structurally easy to arrange an operating lever and that is easy for a seated person to see a position of the operating lever. The chair is so arranged that multiple seat support frames 41 extend from a center portion of a leg support post 3 toward a direction to be directed away gradually, undersurfaces of edge portions of a seat 1 are supported by distal end portions of the seat support frames 41, a portion locating both below the seat 1 and between the seat support frames 41, 41 lying next to each other is left open so that the portion can be used as a function adjusting space A1 through A3 where an operating part is arranged.

Abstract: The present claimed invention intends to provide a chair having a frame structure that is effective for securing a required strength without needless structure to reinforce the strength. The chair has a chair body A comprising a seat frame 12, a back frame 22 and a rib that reinforces between the seat frame 12 and the back frame 22, wherein the rib is formed to extend to a side direction so as to be used as an arm frame 71, and the seat frame 12, the back frame 22 and the arm frame 71 are continuously and integrally formed three-dimensionally, and openings 12a, 22a into which a mesh member 13, 23 to form a seating face is fitted are arranged at the seat frame 12 and the back frame 22 respectively.