Abstract: The invention achieves a chair in which a shape of a backrest surface can be three-dimensionally changed while following a motion such as a sitting person looks around while sitting or the like. In a chair provided with a backrest in which an upper portion of a backrest surface is supported by a plurality of frame elements arranged so as to be spaced with each other in a width direction, the respective frame elements are independently movable backward and forward.

Abstract: The present invention intends to arrange the appearance of furniture at a connecting portion between a first member having stiffness and a second member movable relative to the first member and having stiffness without forming the connecting portion in an unnaturally large diameter. More specifically, the present invention provides a structure for connecting members comprising: a first member having stiffness; a second member movable relative to the first member and having stiffness; and a spring member in which an end portion thereof is connected to the first member and other end portion thereof is connected to the second member so as to accumulate a reaction force by elastic deformation, wherein the spring member is formed into a frame-like shape extending along the first and second members.

Abstract: There is provided a chair that realizes a state preferably following a motion of a sitter in accordance with a posture of the relevant sitter, and a state preferably supporting the sitter. The chair includes a lower frame portion supported so as to be capable of rocking between a standing position and a rearward tilting position with respect to a base, and an upper frame portion supported so as to be capable of rocking between a normal position and a rear end position with respect to the relevant lower frame portion. Furthermore, upper frame portion biasing that elastically biases the upper frame portion from the rear end position to the normal position is provided. This upper frame portion biasing is adapted to change an elastically biasing force to the upper frame portion corresponding to a position in the rocking movement of the lower frame portion.

Abstract: The present invention intends to arrange the appearance of furniture at a connecting portion between a first member having stiffness and a second member movable relative to the first member and having stiffness without forming the connecting portion in an unnaturally large diameter. More specifically, the present invention provides a structure for connecting members comprising: a first member having stiffness; a second member movable relative to the first member and having stiffness; and a spring member in which an end portion thereof is connected to the first member and other end portion thereof is connected to the second member so as to accumulate a reaction force by elastic deformation, wherein the spring member is formed into a frame-like shape extending along the first and second members.

Abstract: A structure intends to arrange the appearance of furniture at a connecting portion between a first member having stiffness and a second member movable relative to the first member and having stiffness without forming the connecting portion in an unnaturally large diameter. More specifically, the present invention provides a structure for connecting members comprising: a first member having stiffness; a second member movable relative to the first member and having stiffness; and a spring member in which an end portion thereof is connected to the first member and other end portion thereof is connected to the second member so as to accumulate a reaction force by elastic deformation, wherein the spring member is formed into a frame-like shape extending along the first and second members.

Abstract: It is a subject to provide a chair capable of realizing a condition in which movements of a seating person are preferably followed and a condition in which a back of the seating person can be preferably supported. For this purpose, a chair C comprising a lower frame portion that is supported to be rockable between a standing position and a rearward tilting position of a back frame with respect to the base and an upper frame portion that is supported to be rockable between a normal position and a rear end position, wherein the chair is further comprised with a movement range setting mechanism with which a movement range through the rocking movement of the upper frame portion with respect to the lower frame portion is made changeable in accordance with the position of the lower frame portion with respect to the base during the rocking movement.

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 structure for attaching a frame-like spring being capable of effectively reducing the number of parts, is provided. According to this structure, a reaction force frame element which is a frame-like spring is attached via a lower frame portion and an upper frame portion so that pressurization is always provided in the movable range and the pressurization becomes the lowest at a predetermined position of a normal posture. Specifically, when the a reaction force frame element is made into the attaching preparation posture that the elastic repulsive forces are accumulated rather than a normal posture, the upper attaching portions include insertion portions for allowing insertion of lower ends and engagement portions to be engaged to the lower end portions due to an elastic repulsive force when the external force is released.

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: There is provided a chair that realizes a state preferably following a motion of a sitter in accordance with a posture of the relevant sitter, and a state preferably supporting the sitter. The chair includes a lower frame portion supported so as to be capable of rocking between a standing position and a rearward tilting position with respect to a base, and an upper frame portion supported so as to be capable of rocking between a normal position and a rear end position with respect to the relevant lower frame portion. Furthermore, upper frame portion biasing means that elastically biases the upper frame portion from the rear end position to the normal position is provided. This upper frame portion biasing means is adapted to change an elastically biasing force to the upper frame portion corresponding to a position in the rocking movement of the lower frame portion.

Abstract: The present invention intends to arrange the appearance of furniture at a connecting portion between a first member having stiffness and a second member movable relative to the first member and having stiffness without forming the connecting portion in an unnaturally large diameter. More specifically, the present invention provides a structure for connecting members comprising: a first member having stiffness; a second member movable relative to the first member and having stiffness; and a spring member in which an end portion thereof is connected to the first member and other end portion thereof is connected to the second member so as to accumulate a reaction force by elastic deformation, wherein the spring member is formed into a frame-like shape extending along the first and second members.

Abstract: A structure for attaching a frame-like spring according to the present invention, being capable of effectively reducing the number of parts, is provided. According to this structure, a reaction force frame element which is a frame-like spring is attached via lower frame portion and an upper frame portion so that a pressurization is always given in the movable range and the pressurization becomes the lowest at a predetermined position of a normal posture. Specially, when the a reaction force frame element is made into the attaching preparation posture that the elastic repulsive forces are accumulated rather than a normal posture, the upper attaching portions include insertion portions for allowing insertion of lower ends and engagement portions to be engaged to the lower end portions due to an elastic repulsive force when the external force is released.

Abstract: It is a subject to provide a chair capable of realizing a condition in which movements of a seating person are preferably followed and a condition in which a back of the seating person can be preferably supported. For this purpose, a chair C comprising a lower frame portion that is supported to be rockable between a standing position and a rearward tilting position of a back frame with respect to the base and an upper frame portion that is supported to be rockable between a normal position and a rear end position, wherein the chair is further comprised with a movement range setting mechanism with which a movement range through the rocking movement of the upper frame portion with respect to the lower frame portion is made changeable in accordance with the position of the lower frame portion with respect to the base during the rocking movement.

Abstract: The invention achieves a chair in which a shape of a backrest surface can be three-dimensionally changed while following a motion such as a sitting person looks around while sitting or the like. In a chair provided with a backrest in which an upper portion of a backrest surface is supported by a plurality of frame elements arranged so as to be spaced with each other in a width direction, the respective frame elements are independently movable backward and forward.

Abstract: In order to adjust a reaction force of a frame-like spring, the invention provides an attachment structure of a reaction force frame element, which is frame-like spring, having an upper end, which is one end, connected to an upper frame element, which is first attaching object, and a lower end, which is the other end, connected to a lower frame element, which is second attaching object, wherein the upper end is attached to the upper frame element through an upper attaching portion, which is first attaching portion, and the lower end is attached to the lower frame element through a lower attaching portion, which is second attaching portion, and, the lower attaching portion is configured to change a relative angle formed by the reaction force frame element and a downward face, which is attaching face, of the lower frame element.