Abstract: A reconfigurable apparatus for sitting and having a seat mounted on a frame and movable under the weight of a sitting user. As an incident of the user sitting, resistance to movement of a back rest component is increased a predetermined amount based upon the user's weight. A manually operable subassembly allows the increased resistance to be changed from the predetermined amount with the user sitting on the seat.

Abstract: A tilt-swivel chair employing a bearing base assembly in communication with connection plate or seat plate of the chair is provided. The tilting mechanism in forward and backward direction is provided by the spring which has a pushing and pulling action and the swiveling action is done along the side axis of the bearing base assembly, and the side axis is a cylindrical shape section with a bushing cap onto which a lever base is equipped and is connected to the connection plate or seat plate. The balance ball feeling is provided with the spring action. A cam and lever mechanism is provided at the base of the side axis in corporation with the base section of the assembly. The cam and lever mechanism provides a smooth swiveling action to the seat and to lock and shut down and take a break.

Abstract: A reconfigurable apparatus for seating a user and having: a frame; a seat movable relative to the frame between: a) a first position in which the seat resides with no user sitting on the seat; and b) a loaded position; a back rest with a changeable angular orientation relative to the frame; and an adjusting assembly having a plurality of gears that move relative to each other as an incident of the seat moving from the first position into the loaded position to thereby cause an increase in resistance to changing of the angular orientation of the back rest.

Abstract: A chair in which a synchronized mechanism, fixed on a telescopic post of a base, supports and renders interdependent rigid elements and which, define respectively the backrest and the seat of the chair and are mutually hinged at a first point, i.e. along a horizontal axis perpendicular to the longitudinal centerline plane of the seating space, which is entirely defined by a single curved line obtained by joining the rigid elements and which are adapted for this purpose.

Abstract: The invention relates to a vehicle seat comprising a backrest portion and a seating surface portion, each of which is arranged to be connected with a seat base portion, wherein the backrest portion is resiliently arranged and supported to be able to swivel with respect to the seat base portion, and wherein the seating surface portion is arranged to be able to move in at least a longitudinal direction of the seat frontwards and rearwards with respect to the seat base portion, wherein the backrest portion and the seating surface portion are operatively connected together via a first lever arrangement in such a way that the seating surface portion is able to move rearwards in the longitudinal direction of the seat when the backrest portion makes a suspending movement with respect to the seat base portion in a direction away from the seating surface portion.

Abstract: 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.

Abstract: A seat assembly forming a substantially horizontal plane for an exposed surface of each of a lower seat cushion and a seatback cushion of a seatback comprises a lifter mechanism for a rearward edge of the lower seat cushion. The lifter mechanism comprises a bracket pivotable about a transverse bar fixedly mounted to a frame assembly for a lower seat assembly, the bracket comprising a forward lever and a rearward lever; and a link pinned at a first end to the seatback and pinned at a second end to the rearward lever by a slot. The rearward edge of the lower seat cushion is initially raised by the forward lever upon the seatback pivoting to a predetermined reclined position and the rearward edge of the lower seat cushion is raised to the substantially horizontal plane upon the seatback pivoting to a fully reclined position.

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: The present invention discloses a chair reclining adjustment mechanism, including a chassis, a turntable rotatably connected to the chassis by using a rotation shaft, and an elastic resetting device that is disposed between the chassis and the turntable and is configured to always enable the turntable to have a moving trend of rotating towards one side of the rotation shaft, wherein a rotation gap is provided between the turntable and the chassis at the other side of the rotation shaft; the adjustment mechanism further includes a locking member capable of entering or slipping out of the rotation gap, a locking component that always enables the locking member to have a moving trend of entering the rotation gap and an unlocking component configured to pull the locking member to slip out of the rotation gap.

Abstract: The present invention provides a chair and a chair lifting adjustment control mechanism thereof. The chair lifting adjustment control mechanism comprises a base, an executing member slidably connected to the base for pressing a pushbutton of a telescoping member, and a cable-driven assembly with one end connected to the executing member to enable the executing member to produce a horizontal displacement. The cable-driven assembly comprises a dragline with one end connected to the executing member, and the executing member has a driving ramp for facing the pushbutton and pressing or relaxing the pushbutton during the horizontal displacement.

Abstract: A tilt mechanism for a weight-responsive seating furniture comprises a backrest support, a first lever and a second lever. The backrest support is configured for coupling to a backrest and is pivotably mounted. The first lever has a mount structure for coupling the first lever to a seat. The first lever is pivotably mounted at a first pivot axis. The second lever is pivotably attached to the backrest support at a second pivot axis and is coupled to the first lever by a coupling mechanism to pivot the first lever about the first pivot axis when the backrest support pivots relative to the carrier.

Abstract: A seating furniture includes a seat device and a backrest device connected via at least one first rotatable coupling in respective coupling portions (P) of the backrest device and at rear portion (B) of the seat device. A base supports the seat device and the backrest device. The backrest device comprises a portion extending in a direction towards the base and past the first rotatable coupling, and the portion is rotatably coupled to and supported on the base via at least one respective link arm. The seat device is rotatably coupled to and supported on the base via a second rotatable coupling attached closer to front end (F) of the seat device than the first rotatable coupling. A lockable control device controls the movements between the backrest device and the seat device. The construction is well-balanced, and low forces are required to adjust the chair in all positions.

Abstract: A mechanism for an office chair has a base support which is placeable on a chair column. A seat support is arranged on the base support and is movable relative to the base support. A backrest support is coupled with the seat support. Pivoting the backrest causes the seat support to move relative to the base support. An alternative solution for adjusting the tilting resistance of the seat support of an office chair is provided where the tilting resistance of the seat support is influenced by the pivoting resistance of the backrest support.

Abstract: A seat back recliner is revealed. A seat back is pivotally connected to and positioned on a rear end of a seat part of a chair while a cylinder is disposed between the seat part and the seat back. A reclined angle of the seat back is adjustable under control of the cylinder. Thereby a user sitting on the chair can directly adjust the seat back to the reclined angle required. The reclined seat back allows a user to lie back and have the greatest level of comfort and relaxation while sitting on the chair.

Abstract: The chair includes a cushion having a chassis, a back and an adjustment structure connected to the chassis. The adjustment structure includes a base frame and a back frame. The base frame has a main body with a connecting arm rotatably connecting the chassis. The back frame is connected between the back and the base frame and has a connecting portion connected to the base frame and a support substantially perpendicularly extending from the connecting portion toward the back. An arc-shaped bend portion is formed between the support and the connecting portion. A top of the support is connected to the back.

Abstract: A (recliner) chair action of relatively movable seat frame (11), (back) drive frame (12) and yoke frame (13), with intervening links (16, 17, 18, 19), independently grouped respectively between seat frame and drive frame and between drive frame and yoke frame; for seat translation and elevation upon back recline operable under a potential energy function in an inter-relationship between back recline and seat movement, for a common or harmonious experience between different occupancy weights.

Abstract: A chair back according to embodiments of the present invention includes a rigid support member for reclinable attachment to a base, a flexible frame member having a flexible frame and a mesh, the mesh at least partially spanning the frame, and a seat attachment member moving in synchronization with the rigid support member at a different rate than the rigid support member during reclining of the rigid support member, wherein a first portion of the flexible frame member is affixed to the rigid support member, wherein a second portion of the flexible frame member flexes freely, wherein the seat attachment member contacts at least part of the second portion of the flexible frame member, wherein the first portion moves with the rigid support member and the second portion moves with the seat attachment member such that a curvature of the second portion increases as the rigid support member reclines.

Abstract: A chair in which a biasing force acting on a back can be changed even if the stroke of a moving member is small, thereby enabling the device to be compact, and the biasing force can be steplessly adjusted with light force. A biasing force transmission member (41) reverses the biasing force of a biasing mechanism acting on a tip portion of the biasing force transmission member (41) which is a point of effort (Q) with a point abutting a fulcrum member (49) working as a fulcrum (P) for a lever, transmits the biasing force to a base end of the biasing force transmission member (41) which is a point load (R) to bias the back in an upright direction, and moves the fulcrum member (49) along a side edge of the biasing force transmission member (41) on a pressure receiving side to be able to adjust the biasing force.

Abstract: Reaction force mechanism for backrest of a chair has clear large space under the seat and uses a longer reaction force spring than the prior art. The mechanism includes a base member supported on a leg, a back support member coupled by a rotation shaft to the base member to recline and support the backrest, a seat support member to which the seat is mounted, a weight-dependent reaction force mechanism for moving the seat support member in a lifting direction, and a reaction force spring for applying a spring force for returning the back support member to an original position, in which the reaction force spring is disposed in a lateral orientation between the back support member and the seat support member.

Abstract: A chair and method of use is for a chair disposed upon a surface that is designed for a female anatomy; the chair includes a seat having proximate and distal end portions forming a first convex surface with a chord plane intersecting, the having a length shorter than its width. The chair includes a back having first and second end portions that form a second convex surface, wherein, a second lateral measure on the second end is less than a first lateral measure on the first end. The seat plane and an extension axis that is perpendicular to the surface are relatively positioned to one another to form an acute angle to one another, such that a user's femur bone lengthwise angles downward from hip to knee toward the surface while the user's shoulders arch rearward thus aligning the user's hip joint and shoulder joint vertically for better posture.

Abstract: A chair includes: a backrest with a waist support projecting part; a horizontal forward seat; a backward seat pivotally supported so as to be able to swing downward relative to the forward seat; a leg support pivotally supported at a front end of the forward seat; links for changing a positional relation between the rear end of the backward seat and the lower end of the backrest so that a distance from the waist support projecting part to the backward seat is reduced from a standing posture to a tilted posture as the backrest is tilted backward; and a connection link for connecting the lower end of the backrest and a part of the leg support lower than the upper end of the leg support so as to cause the leg support to swing forward as the backrest is tilted backward.

Abstract: A modular chair mechanism for limiting travel and adjusting tension in a chair is provided. The chair mechanism generally includes a shuttle that travels inside a housing, with a biasing member that applies tension during travel of the shuttle. An interface is coupled to the shuttle that alters the amount of force required to cause the shuttle to travel. In embodiments, the chair mechanism limits travel of a chair back support assembly to a number of positions based on travel of a shuttle inside the mechanism housing. For example, a feature on an end of the shuttle may selectively abut one of a plurality of retention means on the housing, which determines how far the shuttle may travel in that position. The amount of tension in the biasing member may also be affected by a self-weighing mechanism that applies an initial amount of force against a biasing member.

Abstract: Follow-up performance to respiratory movements is made higher than that of the prior art without obstructing movements of the pelvis of a person. A configuration is adopted that a cushioning member arrangement frame for a seat back 34, 140 and a cushioning member arrangement frame for a seat cushion are displaced according to load fluctuation to a cushioning member for a seat back 40, 150 or a cushioning member for a seat cushion 20. That is, such a configuration is adopted that the cushioning member arrangement frame for a seat back 34, 140 or the cushioning member for a seat cushion 20 not only moves according to load fluctuation but also frames themselves supporting them move via tension structure members spread over the frames (a cushioning member for a seat back and a cushioning member for a seat cushion).

Abstract: A device for an adjustable piece of seating and reclining furniture with an adjustable angle between the seat and the back of the piece of furniture, wherein on each side of the piece of furniture there is located a fitting projecting upwards from its base, the seat being tiltable about a forward suspension point on the fitting, and the back being tiltable about a rear suspension point on the fitting, wherein the back upon tilting backwards causes the seat to tilt backwards in that a link is pivotally fastened to a rear part of the seat frame and pivotally fastened to a lower part of the back frame, the pivotal connection of the link to the back frame being located behind and below said rear suspension point. On an increase in the angle between the seat and the back, the angle that the neck rest of the piece of furniture forms with the back is reduced.

Abstract: A height adjustment mechanism is disclosed that includes a pedestal height variability mechanism. The pedestal height variability mechanism includes a first member and a biasing mechanism. The biasing mechanism is configured to hold the first member in a first position. The first member has a first end and a second end opposite the first end. The biasing mechanism has a first portion attached to the first member adjacent the first end of the first member. The biasing mechanism also has a second portion attached to the first member adjacent to the second end of the first member. Preferably, a second member is also provided that is moveably attached to the first member. The second member may be configured such that movement of the second member actuates height adjustment of a chair.

Abstract: A sliding hinge is mounted between a cover and a body of an electronic device and has a bracket, a linking panel, a slide and a connecting wire. The bracket is attached securely to the cover. The linking panel is attached securely to the body and is mounted slidably on the bracket. The slide is mounted slidably on the bracket. The connecting wire is wound around a fulcrum of the bracket and respectively connects to the linking panel and the slide. The cable of the electronic device is mounted through the slide. When the cover slides relative to the body, the slide and the linking panel relatively move in opposite directions. Therefore, the cable is folded to keep taut.

Abstract: A chair that includes a support module, a seat carrier, an initially forwardly declined seat member articulated to the seat carrier such as by being pivotal along a front, and an initially rearwardly angled backrest carrier having a backrest member, the carrier articulated to the seat carrier such as by being pivotal along a lower end. The angular positions of the seat and backrest member are largely controlled via an actuator arm and adjustable spring arrangement, wherein the actuator arm directly links the seat member to the backrest carrier and the spring arrangement returns the backrest carrier and seat member to initial positions when a weighted load is lessened or removed from the rear of the seat member. A pneumatic cylinder to provide resistance to the seat member, a limiter to limit a maximum and minimum angular position of the seat member, adjustable arm rests, and casters may be included.

Abstract: A chair has a link of a chair back, a link of a chair seat, and a link mechanism that pushes up the link of the chair seat when the link of the chair back is pressed to incline rearward, so that the occupant can take the optimum seating posture without being conscious, thus further improving the comfort in the reclined posture.

Abstract: A seat comprising a seat pan (12) and a support structure, wherein the seat pan (12) is pivotally coupled to the support structure (8) about a first pivot axis (pi) provided across substantially the front of the seat pan (12), such that the seat pan (12) may be pivoted about the said first pivot axis (pi) in use, and the angle of the seat pan (12) relative to the support structure (18) may thus be adjusted. The seat further comprises a backrest (14), the backrest being coupled (p2) to substantially the rear of the seat pan (p12). Also provided is pneumatic apparatus for use with a seat, comprising one or more inflatable cushions for supporting a user in use.

Abstract: A workstation for a user comprising a basis, an shaft pivoted on the basis, a seat pivoted on the shaft, a back rest connected to the shaft, at least one shaft piston connecting the basis to the shaft and at least one seat piston connecting the shaft to the seat. The shaft and the seat are arranged to allow a user to sit at the workstation. The at least one shaft piston and at least one seat piston are arranged to allow changing the position of the shaft and of the seat. The orientation of the shaft and the orientation of the seat are adjustable by the user.

Abstract: A chair has a link of a chair back, a link of a chair seat, and a link mechanism that pushes up the link of the chair seat when the link of the chair back is pressed to incline rearward, so that the occupant can take the optimum seating posture without being conscious, thus further improving the comfort in the reclined posture.

Abstract: An adjusting structure for use in reclining chairs includes a reclining chair including a seat, a chairback, two armrests, a pad and a frame. The frame includes a hydraulic cylinder pivotally disposed on the rear end thereof and two double rodded holders couplingly mounted on two sides thereof respectively. The front ends of the double rodded holders and two swinging members beneath the seat are pivotally connected with a shaft. Each of the double rodded holders includes an offset member affixed on the front end thereof and extending backwardly for coupling with the bottom of the armrest. Also, the pad includes two connecting rods attached on two sides thereof, each connecting rod having two supports secured on the seat and the armrest respectively. The rear sides of the two supports are coupled with the chairback by using a T-shaped piece, thereby enabling the functions of recumbency and force-saving leave from the reclining chair.

Abstract: A work station chair (10) is enabled to shift in response to a person leaning forward in the chair (10) when in a working mode and leaning back in a rest position. The chair includes a seat (18), a backrest (24) and supportive structure. The seat (18) is resiliently supported on the supportive structure (22) and moveably along an arc track (30) which is mounted on the supportive structure and has a radius generated from the ankle of the person sitting on the chair. The backrest (20) is resiliently supported on the seat (18) and moveable along an arc track (64) which is mounted to the seat (18) and has a radius generated from H-point that is a natural pivot point of the torso and thigh lines of the person. The chair (10) provides a combined tilting movement of the person's body about the ankle point and the H-point when the person shifts his or her gravity to reduce adverse static postural loads and forces which are responsible for the fatigue and biomechanical dysfunction.

Abstract: The invention relates to a chair, especially an office or work chair or similar, whereon a back-rest part (15) can be placed in an inclined position from an initial or rest position via a first axis of rotation (12). A seating part (14) performs a longitudinal displacement around a second axis of rotation (20) and an inclined displacement around a third axis of rotation (11) in a synchronous manner with respect to the inclined movement of the back-rest part (15). A return device (13) is provided for returning the back-rest part (15) and/or seating part (14) to the initial position or rest position. The office chair (1) comprises a carrier frame (5) which disposed centrically on the leg frame (2) and which supports in a stationary manner the first axis of rotation (12) on the centre of the leg frame, said axis of rotation remaining at a constant, predetermined distance above the seating part (14) in the rest position and in all inclined positions of the back-rest part (15).

Abstract: An articulating massaging chair is provided that includes a support frame; a seat pivotally connected to the support frame by a seat pivot; and a backrest pivotally connected to the support frame by a backrest pivot.

Abstract: A tilt control mechanism for an office chair includes a spring assembly therein which controls the tilt tension on the back assembly. This tilt control mechanism includes a tension adjustment assembly having a radial adjustment arm which supports the legs of a pair of coil springs and a cooperating cam block which cooperates with the arm to drive the arm upwardly and downwardly to vary the tilt tension. The cam block is mounted on a threaded shaft and is displaceable sidewardly to either drive the arm and spring legs upwardly or downwardly depending upon the direction of travel of the cam block.

Abstract: A chair control mechanism has a rotatable shaft with a radially extending member abutting an actuating finger of a gas control cylinder. A slider may push a second radially extending member of the rotatable shaft in order to rotate the shaft. The slider has a tab extending into the mouth of the head of a further shaft which is rotated by a user operated handle. Thus, when the user operates the handle, the head of the further shaft causes the slider to slide.

Abstract: Disclosed is a videogaming and computer workstation unit, preferably integrated with an ergonomic chair, which permits ease of entry and exit to the chair for users of various sizes, and which permits users to use peripheral devices for operating video games and computers comfortably from a chair integrated with a gaming console.

Abstract: A chair with a synchronous coordinating system for the chair back includes a base, a chair cushion and a chair back. The base and the chair cushion are connected fixedly or formed integrally, and the chair back is articulated with the base which is articulated with the chair back through an upright column extended above the chair cushion. The articulated point is located at the trochanter (the center point of the hip joint) of the human body. The chair cause the turning (pitched or inclined) pivot of the chair back and the human body on the same line by providing the articulated point of the chair back and the base at the trochanter of the human body in the pitching movement. No matter how the angle of the chair back is adjusted, the contact surface between the backside of the human body and the chair back will not be changed so that the chair back can provide sufficient supporting force to the waist at any angle and the person on the chair will not feel uncomfortable.

Abstract: A reclining apparatus is provided between a post and a seat of a chair. The reclining apparatus includes a first joint for attachment to the post, a second joint pivotally connected with the first joint for supporting the seat and a locking device for locking the second joint in one of several reclined positions relative to the casing.

Abstract: A reclining chair system with a standard assembly supporting seat and backrest assemblies, which are pivotally mounted to each other and capable of providing a rocker effect to a user. A strut assembly provides substantially a bounce free shock absorbing function by using two coaxially disposed compressible and resilient members that are compressed sequentially. A headed shaft with a step limits the compression of the first member. The arrangement permits a volumetrically efficient operation while preventing excessive fatigue of the member. An adjustment mechanism permits a user to readily set the relative angular position of backrest and seat with respect to the standard (and consequently the horizontal plane) depending on the location of the chair system.

Abstract: A seating unit includes a base, a seat, a back, and a control operably supporting the seat and the back on the base for movement between upright and recline positions. The control includes a spring providing a biasing supporting force to the back during recline, and further includes a booster mechanism for increasing the supporting force, and still further includes a stop member and a selector device for activating and deactivating the booster mechanism. The selector device is easily movable with a low effort that is independent from friction generated by internal components of the booster mechanism. The stop member is linearly slidably mounted atop a control housing for selectively engaging the booster mechanism and the link for movement between a disengaged position, a booster-engaged position, a partial-recline position, and a recline-prevented position.

Abstract: A chair has a seat and a backrest, a structure supporting the seat, and a base. The support structure has two lateral uprights and at least one projecting element provided with a substantially longitudinal guide. The backrest is associated with two angled elements; each of the angled elements has a first end connected to the backrest, a central part connected rotatably by a first hinging pin to a top end of one of the uprights of the support structure of the seat, and a second end connected by a second hinging pin to the seat. The seat is connected to the support structure by a telescopic rod, which can be shortened and lengthened in a resilient manner, and an element which can be slidably engaged in the guide of the projecting element.

Abstract: In order to provide a chair that can support near a pelvis or a lumbar portion of a person who sits on the chair irrespective of a body proportion the person or a way to sit, a boundary portion K between a back and a seat is arranged to be transformable or movable and the boundary portion K can be fixed at a position where the boundary K pushes against near the pelvis of the person with an operation from outside

Abstract: This object is attained in a chair comprising a pedestal; a seat support supported thereon via a chair column, said seat support comprising a front and a rear seat support element being connected with one another via a pivot axis extending substantially horizontally; a seat supported on said seat support elements; a backrest secured on said rear seat support element; a longitudinally adjustable energy storing means for mutually adjusting said backrest and said seat, said energy storing means being joined with said seat support elements at a distance from their pivot axis; a spring abutment being arranged pivotably around said pivot axis for adjustably dampening a pivoting movement of said seat support elements relative to one another; an adjusting element extending substantially tangentially relative to said pivot axis and being pivotable around an adjusting element pivot axis for modifying the bias between said spring abutment and one seat support element; and an actuating twist handle connected with said ad

Abstract: The invention discloses an armchair (1) with variable position comprising a support structure (2) having a post (3) defining a first vertical axis (Z), a first frame (8) comprising a first pivot (9) defining a second horizontal axis (X), a second frame (12) swinging at one end (11) around the first pivot (9), thrust means (14) connected to the first frame (8) and acting against the end (11) of frame (12) to resist its swinging movement around the axis (X), a seat (10) supported by the first frame (8) and a backrest (13) supported by the second frame (12). The seat (10) is connected at least to the first frame (8) through first elastic means (15) adapted to allow a rotary translatory motion to the seat (10). The backrest (13) is connected to the second frame (12) through second elastic means (22) to allow a further rotary translatory motion.

Abstract: A chair 1 allowing a person sitting thereon to move a part of the person's body above the waist which corresponds to the backrest of the chair is provided having a backrest portion located behind a seat portion, the backrest portion being divided into backrest upper frames 55 and backrest lower frames 50, wherein a first state which allows the whole backrest frame 5 to incline rearwardly and a second state which allows the backrest upper frames 55 to incline rearwardly relative to the backrest lower frames 50 are assumed, the first state and the second state being switchable to each other.

Abstract: An item of seating furniture having a seat and a backrest which are supported in an articulated manner on a frame, and having an operating mechanism for adjusting the inclination of the seat and the backrest. The backrest has a catch member and, when the backrest is inclined from a front position into an inclined rear position, the catch member comes into operative contact with the seat as of a specific angle of inclination of the backrest in such a manner that further inclination of the backrest brings about a simultaneous adjustment of the seat.

Abstract: A spring unit (11) for the weight setting of a chair (1), in particular an office chair, having a gas spring (12) and having a number of further spring elements (17, 18, 19; 27, 28) which can be connected up to the gas spring (12) individually or in combination. The spring unit (11) is expediently arranged between a seat carrier (7) connected to a rotary column (8) of the chair (1), and the seat (3), or a backrest link (4) which extends at least approximately parallel to said seat (3) and belongs to a backrest (2).

Abstract: An ergonomic chair includes a four-bar linkage arrangement wherein a lower frame member is provided with a rigid front support and a rigid rear support with a seat member pivotably connected to the front support. A back rest has an upper support pivotably connected at an upper end of the rear support of the lower frame member. A link member pivotably connects at a first end to a rear support of the seat member and at second end to a lower support of the back rest. This novel arrangement permits tilting movement of the backrest rearwardly relative to the lower frame member causing elevation of a rear portion of the seat member, permitting the feet to remain on the floor and alleviating pressure on the user's thighs.