A seat with a base, an actuator, at least one front boom, at least one rear boom, a seat platform, and a back platform. The actuator is circularly rotatably connected to each of the at least one front boom, the at least one rear boom, the seat platform, and the back platform. The base is circularly rotatably connected to each of the at least one front boom and the at least one rear boom.

A chair component assembly includes a support component adapted to support a portion of a seated user, and a cover including a plurality of sides that cooperate to form an interior space that receives the support component therein, the cover further including a support component receiving aperture and a flap movable between an open position where the support component may be moved from an exterior of the cover to the interior space of the cover, and a closed position where the flap covers the support component receiving aperture, and wherein the flap is secured to the support component by a quick-connect fastener.

An oscillation system (1) for chairs includes a backrest support (3) oscillating about a rotation axis (4), a first support element (6) of the seat coupled to the frame (2) to assume, in the at rest position of the backrest support (3), a plurality of relative vertical positions with respect to the frame (2) depending on, and by effect of, a weight force applied to the first support element (6). A first elastic element (21) opposes an elastic reaction to the backrest support oscillation with respect to an at rest position of the backrest support (3). A lever (31) connects to the first support element (6) to be rotated by the first support element (6) during variation of the relative position, and connects to the first anchoring end (22) to displace the first anchoring end (22). A fulcrum axis (60) does not coincide with the rotation axis (4).

A chair provided with a plate, to which a seat is freely articulated above, by way of at least one first linkage and a second pair of linkages in the rear and front regions, a backrest being articulated laterally and freely to said seat.

The first end of a pair of cams is pivoted to the plate at the rear, and the second end is pivoted to the backrest.

The pair of cams has arc-like guiding means for the sliding of at least one seventh pivot which is integral with and protrudes from the backrest.

The first linkage, the second pair of linkages and the pair of cams are adapted to force the forward and downward movement of the seat with respect to a backward inclination that can be imparted to the backrest.

A chair can include a chair back, or backrest, that is coupled to a base of a chair above a seat of the chair. A tilt mechanism can attach the backrest to the base at spaced apart locations. In some embodiments, the tilt mechanism can be configured so that the backrest rotates about multiple pivots as it reclines from an upright position to a reclined position to drive forward motion of the seat during recline of the backrest.

A mechanism for adjusting the seat of a chair as a result of changing the tilt of the backrest with respect to the seat is provided. The mechanism has a backrest frame and a base frame, as well as a covering element stably combined with the base frame and forming part of the seat. The backrest frame is rotatably constrained to the base frame around a respective rotation axis and tilting with respect to the seat between a position (P1) of minimum tilt and a position (P2) of maximum tilt. Advantageously, the covering element is partially elastically deformable, with the mechanism having deforming means operated by the backrest frame in order to reversibly deform, in the vertical direction, when the covering element as a function of the tilt angle with backrest frame has reached with respect to the position (P1) of minimum tilt.

The invention relates to a seat (1), in particular an office chair, comprising a seat support (3) for a seating surface (6) and comprising a backrest support (4) of a backrest (5), which is held on the seat support (3) so as to be able to move in a tiltable manner to the side, wherein the backrest support (4) comprises two support arms (4a, 4b) which are configured to be flexible and/or articulated laterally and spaced apart from one another. Preferably, the seating surface (6) and/or the backrest (5) comprises a curved seat shell and/or backrest shell (6a, 5a) provided with a cover (6b, 5b) with a number of flexible curved ribs (15, 16) on the edge of the shell, wherein the cover is stretched by the seat shell and/or backrest shell (6a, 5a) such that when the cover (6b, 5b) is loaded, the bending of the curved ribs (15, 16) is altered.

An office chair comprises a seat element (3) mounted movably on a fixed support element (1) and a back support element (2). The arrangement simultaneously allows the seat element (3) to move and tilt backwards when the user leans backwards. The seat element (3) carries the chair seating panel (4) in such a way that when the user leans to a side, said chair seating panel (4) tilts to the same side according to the user's movement and independently of the chair's back element (2).

An elastic seesaw-type tilting mechanism is provided, including: a base support, configured to be connected with a chair base through a chair column; a seat support, being pivotably mounted on the base support and configured to be connected with a seat; a backrest support, being pivotably mounted on the base support and configured to be connected with a backrest; a first elastic mechanism, being connected with the seat support and the backrest support to form an elastic seesaw mechanism; a second elastic mechanism, being connected with the base support and the seat support, the second elastic mechanism and the first elastic mechanism being respectively biased against the seat support in opposite directions. A swivel chair is further provided, including: one of the elastic seesaw-type tilting mechanism as described above, a seat, a backrest, a chair column and a chair base.

A tilting mechanism (1) for chairs includes a support frame (2), a structure (4) rotationally coupled to the support frame. An elastic system (80) is interposed between the support frame and the structure to counteract a reaction to the tilting of the structure from an at-rest position to a tilted position. An adjustment system (20) is capable of varying the reaction to the tilting. The elastic system (80) includes at least one elastic element (12) and a first and a second stop element (81, 82) fastened at respective longitudinal end portions of the elastic element, respectively. In the at-rest position, the first and second stop elements are in contact with each other, and the elastic element (12) is in a deformed configuration and generates a residual elastic force that is at least partially released on the first and second stop elements.