Abstract: A rotatable office chair comprises at least two seat carriers, each further comprising an upper arched guide and a lower arched guide, and at least two back rest carriers, each further comprising a restrictedly guided region, and a back rest arranged on back rest carriers, wherein the restrictedly guided region of the at least one back rest carrier is guided between the upper arched guide and the lower arched guide of the at least one seat carrier, thus allowing the at least one back rest carrier to be inclined relative to the seat carrier, wherein the upper arched guide and the lower arched guide are embodied at least in certain regions as an arc of a circle portion and wherein the arc of a circle portion of the upper arched guide and the arc of a circle portion of the lower arched guide have the same center of a circle.

Abstract: The present invention relates to a chair or armchair, in particular a rotatable office chair, comprising: at least two seat carriers, each further comprising an upper arched guide and a lower arched guide, and at least two back rest carriers, each further comprising a restrictedly guided region, and a back rest arranged on back rest carriers, wherein the restrictedly guided region of the at least one back rest carrier is guided between the upper arched guide and the lower arched guide of the at least one seat carrier, thus allowing the at least one back rest carrier to be inclined relative to the seat carrier, wherein the upper arched guide and the lower arched guide are embodied at least in certain regions as an arc of a circle portion and wherein the arc of a circle portion of the upper arched guide and the arc of a circle portion of the lower arched guide have the same centre of a circle H.

Abstract: A chair, in particular a work or office chair, having a seat mounted onto a chair frame. The front region of the seat can be inclined about a horizontal, pivoting shaft which is displaced upwards and downwards, following a spatial guide curve in relation to the chair frame. The seat is also connected in an articulated manner to a rocker which is directed upwards and extends backwards from an articulated rocker bearing fixed to the chair frame and which is connected at a distance from the rear edge of the seat, or at the side of said seat. The chair also includes a backrest which is attached to the section of the rocker that is directed upwards, the inclination of the backrest being disproportionately altered, in a forced manner, with the alteration of the inclination of the seat.

Abstract: The invention relates to a chair, in particular a work or office chair, comprising a seat (5) mounted onto a chair frame (13). The front region of said seat can be inclined about a horizontal, pivoting shaft (15) which is displaced upwards and downwards, following a spatial guide curve in relation to the chair frame (13). Said seat is also connected in an articulated manner to a rocker (7) which is directed upwards and extends backwards from an articulated rocker hearing (12) fixed to the chair frame and which is connected at a distance from the rear edge of the seat, or at the side of said seat (5). The chair also comprises a backrest (4) which is attached to the section of the rocker (7) that is directed upwards, the inclination of said backrest being disproportionately altered, in a forced manner, with the alteration of the inclination of the seat (5). The invention aims to achieve an increased apex angle between the backrest and the seat, together with a uniform displacement.