Abstract: In order to secure a shape retaining property of a support face of a backrest 1 of a chair, the backrest 1 for chairs comprises frame elements 21 and 22 arranged in pairs at right and left sides, a flexible support member 3 that bridges the frame elements 21 and 22 to support a load of a body of a seated person and an adjust mechanism that can change a bent degree of the support member 3 in multiple states and that can maintain the state against the load of the seated person.

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: In order to secure a shape retaining property of a support face of a backrest 1 of a chair, the backrest 1 for chairs comprises frame elements 21 and 22 arranged in pairs at right and left sides, a flexible support member 3 that bridges the frame elements 21 and 22 to support a load of a body of a seated person and an adjust mechanism that can change a bent degree of the support member 3 in multiple states and that can maintain the state against the load of the seated person.

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.

Abstract: A simple arrangement of a chair allows transformation of the shape of a backrest. The chair has a transformable backrest and a backrest receiving member that supports a bottom end portion of the backrest in a slidable manner toward a certain direction and an operating lever to select and fix a position at which the backrest is slid and the backrest can be transformed in compliance with the position fixed by the operating lever.

Abstract: A chair includes a seat portion 1(1B), a seat support 2(2B) supporting the seat portion 1, a rear seat support 3(3B) extending rearwardly upwardly relative to the seat support 2(2B), and a slide mechanism X1 (moving mechanism XB) for causing the seat portion 1(1B) to slide back and forth relative to the seat support 2 (2B). The chair is provided with a locking mechanism 100C for locking the seat portion 6C at a desired position in the fore-and-aft direction selectively, and a lever 110C for operating the locking mechanism 100C, the lever 110C being located at a position allowing the lever 110C to move together with the seat portion 6C in the fore-and-aft direction.