An ergonomically improved chair in which the user's thoracic region is supported by a narrow and generally flat or moderately convex thoracic cushion in the midrest region of the chairback. The design omits or greatly minimizes support for the user's scapulae and other areas of the back outside the thoracic region, excepting lumbar and cervical support features in some embodiments. The design differs from the prior art at least in that the thoracic cushion is narrow and configured not to complement that user's spinal curvature. By appropriate selection and design, a chair incorporating the invention may comprise a fabric covering portions of the chairback without significantly affecting functionality. Other embodiments include a chairback comprising regions having differing levels of firmness and/or differing cushion height at appropriate regions to promote concentrated support of the user's thoracic region.

A chair back (2) comprising an upper back rest section (2), and a lower section (30) adapted to support the back rest section (2) relative to a chair seat (14), wherein the lower section (30) comprises a pair of resiliently flexible arcuate bands (4).

A chair back (2) comprising an upper back rest section (2), and a lower section (30) adapted to support the back rest section (2) relative to a chair seat (14), wherein the lower section (30) comprises a pair of resiliently flexible arcuate bands (4).

Described is a passenger seat that includes a seat bottom assembly (201) with a forward edge and a rear edge and a seat back assembly (101) extending up from the rear edge of the seat bottom assembly (201). The seat back assembly (101) may include a frame (103), a plurality of panels (104-107) within a perimeter of the frame (103), and at least one attachment member (161) configured to attach the plurality of panels (104-107) to the frame (103). The seat bottom assembly (201) may include a frame (203) and a plurality of panels (204,205,206) within a perimeter of the frame (103).

An adjustable chair has a seat and a splat. The seat has a lower base, an upper base, a tilt adjusting device, a lower rotating shaft, and an upper rotating shaft. The lower base has an assembling space. The upper base is movably deposited on the lower base. The tilt adjusting device is deposited in the assembling space. The lower rotating shaft is rotatably deposited in the lower base and connected to the tilt adjusting device. The upper rotating shaft is deposited in the upper base. The splat is tiltably connected to the seat and has a backrest unit and two connecting legs. The backrest unit is deposited at a rear side of the seat. The connecting legs are connected to the backrest unit, are connected to the lower rotating shaft, and are pivotally connected to the upper rotating shaft.

A back adjusting and positioning structure of a chair is characterized in that: a backward tilt adjustment unit is disposed at the junction of a cushion frame and a back frame of the chair so that the backward tilt adjustment unit drives a screw segment with one end thereof extending inward to retract and/or protrude a blocking element coupled to a rear segment thereof in response to a knob's rotating in a predetermined direction, so as to control compression and/or expansion of a predetermined stop distance acquired by a spring fitted in the backward tilt adjustment unit, and in consequence the back in operation attains the required tightening and/or loosening state.

A back adjusting and positioning structure of a chair is characterized in that: a backward tilt adjustment unit is disposed at the junction of a cushion frame and a back frame of the chair so that the backward tilt adjustment unit drives a screw segment with one end thereof extending inward to retract and/or protrude a blocking element coupled to a rear segment thereof in response to a knob's rotating in a predetermined direction, so as to control compression and/or expansion of a predetermined stop distance acquired by a spring fitted in the backward tilt adjustment unit, and in consequence the back in operation attains the required tightening and/or loosening state.

The invention relates to a chair, in particular a conference or visitor chair, which allows a coupled movement of a seat (3) and a backrest. The seat in this case is mounted in sliding bearings (4) comprising oblique guide surfaces (6) and is displaced and raised in the sliding bearings through a mounting end (5) of the backrest. According to the invention, two separate backrest bars (11) are provided, which are connected to the mounting ends (5), wherein the backrest bars can be moved independently of each other. In this way, different seat positions can be realized. Besides an upright standard position, an inclined high position, and an asymmetrical position, in which a one-sided load of a backrest bar (11) can be realized with a corresponding displacement and rotation of the seat (3).

A backrest for an office chair. The backrest has a support structure on which a backrest shell element can be fastened. The support structure is formed with two braces that which are interconnected at upper and lower end regions and that are spaced from each other between the upper and lower end regions. At least sections of the braces are movable relative to one another.

A backrest for an office chair. The backrest has a support structure on which a backrest shell element can be fastened. The support structure is formed with two braces that which are interconnected at upper and lower end regions and that are spaced from each other between the upper and lower end regions. At least sections of the braces are movable relative to one another.