Abstract: The invention relates to a backrest support for a seating furniture, in particular for an office chair. In order to provide a piece of seating furniture having a backrest, in the case of which particularly simple and safe installation and removal of the backrest is possible, it is proposed to design the backrest support (2) in two parts, having a first support part (4), which is connectable to a second support part (5) without a tool, with a releasable connection being formed, wherein, in the assembled state, the position of the two support parts (4, 5) with respect to each other can be secured without a tool by means of a lock (6).

Abstract: An office chair has an armrest. In order to provide an armrest which is of particularly simple construction, the armrest contains an armrest column and an arm support which is mounted on the armrest column and is rotatable about a rotation axis and which is linearly displaceable relative to the armrest column. A rotary mechanism for the rotation of the arm support is arranged substantially fully within the armrest column.

Abstract: A support for a piece of seating furniture provides an additional degree of freedom of movement. The support has a connecting unit fitted on a main body that connects to a supporting element of an underframe. The connecting unit has a mounting device for the supporting element, in particular a mount for the upper end of the supporting element. The connecting unit is fitted on the main body such that it is possible to alter the inclination of the main body relative to the supporting element. For that purpose the main body has a preferably convex contact base, which in the fitted state is contacted by a contact head of the connecting unit, with the abutment forming a non-planar contact rather than a contact over a surface area, in particular a punctiform contact.

Abstract: A chair, in particular an office chair, has a seat inclination mechanism. A transverse strut of the seat inclination mechanism forms a spring device and this spring device has at least one torsion element. The seat inclination mechanism further has a basic support on which a backrest support and a seat element support are articulated. The transverse strut of the seat inclination mechanism forms a spring device. The transverse strut extends in the chair transverse direction and wherein the spring device has at least one torsion element, in particular a torsion bar spring. The torsion element, together with the basic support and/or the backrest support and/or the seat element support, is formed integrally, in particular in one piece, from plastic.

Abstract: A mechanism is provided for an office chair. In order to accomplish an advantageous motion characteristic of the mechanism and thus of the office chair, a synchronized mechanism provides a correlated seat/backrest movement of an office chair. The backrest support is connected to the seat support not directly and immediately, but via a coupling element. The force applied to the seat support upon swiveling the backrest support is applied to the seat support solely via the coupling element. Two guide element pairs are provided to guide the seat support relative to the base support.

Abstract: An armrest, in particular for an office chair, achieves improved handling and adjustability in an individual and in a particularly variable manner by providing a preferably height-adjustable armrest column, an arm support carrier which is mounted on the armrest column and which is rotatable about a first rotational axis, and an arm support which is mounted on the arm support carrier. The arm support is rotatable about a second rotational axis and is displaceable in a linear manner relative to the arm support carrier. The two rotational axes are spaced apart from one another.

Abstract: A mechanism for a chair is particularly suited for an office chair. In order to improve the sitting comfort of a chair, the mechanism has a base support to be placed on a chair column, a seat support disposed on the base support and movable in the longitudinal direction of the chair relative to the base support, and a backrest support which is connected to the seat support. The seat support includes first and second seat support elements. The second seat support element is movable transversely with respect to the longitudinal direction of the chair relative to the first seat support element and/or the backrest support includes first and second backrest support elements. The second backrest support element is rotatable relative to the first backrest support element about a rotational axis which lies in the longitudinal direction of the chair.

Abstract: A height-adjustable armrest for a chair, in particular an office chair, has an arm support, which is retained by an armrest holder. The armrest holder is pivotable and a pivoting causes the armrest to be adjusted in height. An arresting device fixes the armrest holder in a height position. The arresting device is arranged at the upper, alterable-height end of the armrest holder and has a linearly movable latching element. The latching element is connected via a guide element to the armrest holder such that each pivoting movement of the armrest holder induces a linear movement of the latching element.

Abstract: A chair, in particular an office chair, has a backrest which is coupled to a seat support by way of a backrest support. The chair further has a seat face. For tool-free chair assembly the backrest support is constructed in two pieces having a first support member which is associated with the seat support and having a second support member which is associated with the backrest and which is joined to the seat-support-side first support member in a positive-locking plug type connection and is locked therein.