Abstract: Mounts are provided on the inside surface of the left and the right sides of a seat cover on the underside of a chair, and positioning pins with heads and fastening members are provided on the upper surfaces of the bases of armrests. Each mount includes positioning holes respectively having holes for the heads of the positioning pins to be passed through and slits of a width allowing the rods of the positioning pins to be fitted in, and a support hole for the fastening member to be engaged in. When the positioning pins are located at the rear ends of the slits of the positioning holes, the armrests is fixed to the mounts through the support holes by the fastening members. Thus the armrests are removably, assembled with the chair body.

Abstract: The present device relates to a chair in which a base member is fitted onto an upper portion of a leg comprising a plurality of castors in contact with a floor together with support members for these castors, and a seat portion and a back rest are provided on an upper portion of a support plate that is capable of reclining with respect to the base member. This chair is also provided with a cam-shaped link capable of rotating about the periphery of a pin provided in the base member, an upper portion of the link protrudes towards the support plate side, and a corresponding elastic member that is compressed by the rotation of the link is provided in a bottom portion of the base member. A shaft portion in contact with the link, and which causes the link to change profile in response to the reclining action, is provided within the support plate. This configuration provides a chair that is inexpensive and can naturally adopt either a serious working position or a relaxed reclining position.

Abstract: Mounts are provided on the inside surface of the left and the right sides of a seat cover on the underside of a chair, and positioning pins with heads and fastening members are provided on the upper surfaces of the bases of armrests. Each mount includes keyholed-shaped positioning holes respectively having holes for insertion of the heads of the positioning pins and slits of a width suitable for slidably receiving the rods of the positioning pins. Each mount also includes a support hole for the fastening member to be engaged in. When the positioning pins are located at the rear ends of the slits of the positioning holes, the armrest is fixed to the mount through the support hole by the fastening member. Thus the armrests are removably assembled with the chair body. The seat cover has upper and lower protrusions which contact the mount and the base of the armrest, respectively. The mount is bent so that its outboard and inboard portions are inclined relative to each other.