Abstract: A chair includes a leg 1, a seat 5 including a pressure receiving surface PS, a backrest 6, and a support mechanism SM. The seat 5 can move in the front-rear or left-right direction along a predetermined trajectory and to downwardly incline a tip side of the seat 5 in a movement direction in accordance with a movement of the seat 5 from a predetermined reference position (S). The support mechanism SM includes a return-force generation unit configured to generate, in accordance with an amount of movement, a return force in a direction in which the seat 5 moved from the reference position (S) in the front-rear or left-right direction is returned to the reference position (S), and movably supports the backrest 6 in the left-right direction together with a movement of the seat 5 in the left-right direction.

Abstract: A chair is realized which takes specific measures to suppress movement of a seat in a front-rear direction when the seat swings in the front-rear and the left-right directions with respect to a support base. For the purpose, the chair wherein a seat 5 swings in the front-rear and left-right directions with respect to a support base 2, the chair is configured such that swinging of the seat 5 in front-rear direction with respect to the support base 2 is capable of being suppressed at one or a plurality of predetermined positions, or arbitrary position via operation of operation member 152.

Abstract: A chair includes a leg 1, a seat 5 including a pressure receiving surface PS, a backrest 6, and a support mechanism SM. The seat 5 can move in the front-rear or left-right direction along a predetermined trajectory and to downwardly incline a tip side of the seat 5 in a movement direction in accordance with a movement of the seat 5 from a predetermined reference position (S). The support mechanism SM includes a return-force generation unit configured to generate, in accordance with an amount of movement, a return force in a direction in which the seat 5 moved from the reference position (S) in the front-rear or left-right direction is returned to the reference position (S), and movably supports the backrest 6 in the left-right direction together with a movement of the seat 5 in the left-right direction.

Abstract: [Problem] Provided is a chair capable of changing an operation of a movable part between allowed and suppressed states, without causing an up-down movement of a seat or without requiring a complicated structure relying on a back. [Solution] For that purpose, a weight-receiving part 50, the height position of which changes due to a person sitting on a seat surface, is provided on a seat 5, the change of the height position is mechanically transmitted to a control mechanism 8X configured to control an operation of a front-rear swing part 3 being the movable part, and the control mechanism 8X changes an operation of the front-rear swing part-3 being the movable part between allowed and suppressed states.

Abstract: In view of various movement of a seated person, when giving the left-right swinging operation to the seat in the non-conventional aspect, a chair configured such that the back can perform a new movement suitable for the left-right movement of the seat and return to the predetermined position when the seated person leaves a seat, is realized. For the purpose, a back 6 is arranged behind a seat 5, and the back 6 has an operation mechanism 6M turning-movably supporting the load received from a seated person in a left-right direction in a front view, and when the load is applied, at least a part of guide part 65a, 66a of the operation mechanism 6M is separated and the back moves freely, and when the applied load is removed, the back automatically returns to the neutral position along the guide part 65a, 66a.

Abstract: A flange part 31b is provided on a vertical surface 31a on the plate member PM of the front-rear swing part 3, the flange part 31b has a guide surface 31b1 extending to lateral direction and moving the rolling body 45 in the longitudinal direction, a lateral direction dimension of the guide surface 31b1 is greater than a thickness of the plate member PM, the flange part 31b and the portion of the plate member PM forming the vertical surface 31a around the flange part 31b are integrally formed of metal; and the flange part 31b has a shape that goes around the circumference of the guide hole 34 opened in the vertical surface 31a, and then, the rolling body 45 are provided independently to the left and right, to be able to a roll along the guide surface 31b1.

Abstract: A chair according to the present invention is a chair comprising a leg 1 arranged on a floor surface, a leg support pole 13 erected from the leg 1, a support base 4 fixed at an upper end of the leg support pole 13, a seat 2 arranged above the support base 4 and a support mechanism 5 interposed between the support base 4 and the seat 2 and configured to support the seat 2 movably in a front-rear direction and a left-right direction. Additionally, in the support mechanism 5, a left-right support part 51 is attached to the support base 4 movably in a left-right direction, a front-rear part 52 is attached to the left-right support part 51 movably in a front-rear direction, the seat 2 is attached to the front-rear support part 51, and the support base 4 has an arm attachment part 6.

Abstract: A chair is realized which takes specific measures to suppress movement of a seat in a front-rear direction when the seat swings in the front-rear and the left-right directions with respect to a support base. For the purpose, the chair wherein a seat 5 swings in the front-rear and left-right directions with respect to a support base 2, the chair is configured such that swinging of the seat 5 in front-rear direction with respect to the support base 2 is capable of being suppressed at one or a plurality of predetermined positions, or arbitrary position via operation of operation member 152.

Abstract: A flange part 31b is provided on a vertical surface 31a on the plate member PM of the front-rear swing part 3, the flange part 31b has a guide surface 31b1 extending to lateral direction and moving the rolling body 45 in the longitudinal direction, a lateral direction dimension of the guide surface 31b1 is greater than a thickness of the plate member PM, the flange part 31b and the portion of the plate member PM forming the vertical surface 31a around the flange part 31b are integrally formed of metal; and the flange part 31b has a shape that goes around the circumference of the guide hole 34 opened in the vertical surface 31a, and then, the rolling body 45 are provided independently to the left and right, to be able to a roll along the guide surface 31b1.

Abstract: [Problem] Provided is a chair capable of changing an operation of a movable part between allowed and suppressed states, without causing an up-down movement of a seat or without requiring a complicated structure relying on a back. [Solution] For that purpose, a weight-receiving part 50, the height position of which changes due to a person sitting on a seat surface, is provided on a seat 5, the change of the height position is mechanically transmitted to a control mechanism 8X configured to control an operation of a front-rear swing part 3 being the movable part, and the control mechanism 8X changes an operation of the front-rear swing part-3 being the movable part between allowed and suppressed states.

Abstract: In view of various movement of a seated person, when giving the left-right swinging operation to the seat in the non-conventional aspect, a chair configured such that the back can perform a new movement suitable for the left-right movement of the seat and return to the predetermined position when the seated person leaves a seat, is realized. For the purpose, a back 6 is arranged behind a seat 5, and the back 6 has an operation mechanism 6M turning-movably supporting the load received from a seated person in a left-right direction in a front view, and when the load is applied, at least a part of guide part 65a, 66a of the operation mechanism 6M is separated and the back moves freely, and when the applied load is removed, the back automatically returns to the neutral position along the guide part 65a, 66a.

Abstract: A chair according to the present invention is a chair comprising a leg 1 arranged on a floor surface, a leg support pole 13 erected from the leg 1, a support base 4 fixed at an upper end of the leg support pole 13, a seat 2 arranged above the support base 4 and a support mechanism 5 interposed between the support base 4 and the seat 2 and configured to support the seat 2 movably in a front-rear direction and a left-right direction. Additionally, in the support mechanism 5, a left-right support part 51 is attached to the support base 4 movably in a left-right direction, a front-rear part 52 is attached to the left-right support part 51 movably in a front-rear direction, the seat 2 is attached to the front-rear support part 51, and the support base 4 has an arm attachment part 6.