Abstract: The elastic support structure for human body to lean against includes a connecting frame, a swing rack, and an elastic rod. The connecting frame includes a connecting surface and a positioning part for the support structure. The swing rack has its first end placed on one end of the connecting frame, which makes the second end of the swing rack swing. At least two elastic rods are placed on the same side of the connecting frame and swing rack, and two movable parts of the support structure. A multi-directional swing is created. The movable part of the support structure uses the swing feature of the second end of the swing rack, so that the movable part creates a greater range of swing in the corresponding direction.

Abstract: A “task” chair intended primarily for a person working at a computer terminal has a back provided with a pair of upright struts that incorporate respective parallelogram linkages operative to increase the curvature of the lumbar region of the seat back while at least substantially maintaining the contour of the upper region of the backrest when a person leans back in the chair.

Abstract: A chair comprising a support structure bearing a seat and a backrest, in which the backrest comprises a bearing portion and a connecting portion for connection to the support structure, in which the backrest is tiltable rearwards relative to a resting position under a rearwards thrust applied by the user and elastically returns to the resting position when the rearwards thrust ceases. The rearwards tilting of the backrest is formed in part by an elastic detonation of the bearing portion and in part by a displacement of at least a part of the connecting portion relative to the support structure.

Abstract: This present invention discloses a seat, comprising: a seat cushion; and a seat back frame connected to the seat cushion, the seat back frames being bent in a range of specified bending angle in a direction of moving the top end backward by a backward load over a predetermined value, by way of a joint provided at an intermediate portion in the vertical direction, such that the seat back frame receives a reaction force corresponding to the bending angle.

Abstract: A flexible chair back provides a preferred elastic effect than conventional plastic chair backs, which comprises a back supporting board having a flexible member integrally extended from the back supporting board, a rear board and a spring sandwiched by the back supporting board and the rear board. The spring enhances the elasticity of the flexible member, so that the flexible member pushes a seated person's back quite adaptively, and therefore a person can sit against the chair back with comfort for a long period of time.

Abstract: A vehicle seat comprising a rigid support structure provided with a rear central beam, which structure carries a headrest, a seat proper, and a seat back carried by the central beam. The seat back is pivotally mounted on the central beam via two couplings that enable the seat back to move rearwards, under a force greater than a predetermined limit value.

Abstract: A chair with a flexible resilient back support structure includes a hollow tubular seat frame, a hollow tubular backrest frame pivotally connected to the seat frame, and a limit stop affixed to the backrest frame or the seat frame adjacent to the pivot points. The limit stop is configured to limit a degree of rotation of the backrest frame between an upright position and a maximum backwardly rotated position. An elongate spring element extends from within the backrest frame into the seat frame, and is configured to bias the backrest frame in the upright position, and to resiliently resist backward rotation. In various embodiments, a cam surface is associated with the spring element, providing an effective fulcrum point which moves rearwardly as the backrest frame reclines, thereby increasing the effective flexural resistance of the spring element during reclining.

Abstract: A cushion includes a flexible curved main body having a first end formed with a fixed portion and a second end formed with a movable portion, and an elastic mechanism mounted on the main body and biased between the fixed portion and the movable portion of the main body. Thus, the elastic mechanism is stretched by the movable portion of the main body to mate with variation of the curvature of the main body, so that when the main body is pressed and deformed by the user's weight, the main body has a greater elastic action, and the curvature of the main body is changed automatically by the elastic force of the elastic mechanism so as to fit users of different statures and weights.

Abstract: A chair comprises a frame, a chair back, and a chair back return device. The chair back is mounted to the frame for pivotable movement away from a home position. The chair back return device is arranged to return the chair back to the home position.

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 stackable chair includes a seat assembly and flexible back support having a seat spring system attached therebetween. The seat assembly includes seat sides having spaced apart rear portions. The back support includes lower ends curved forwardly and disposed in registry with and separated by right and left gaps from respective seat side rear portions. Right and left spring members are disposed inwardly adjacent to bridge each gap. Each spring member includes forward ends connected to respective right and left front support members extended inbound from respective seat sides, and includes rear ends connected to opposed ends of a frame rear cross-member. The spring members allow limited reclining movement of the back frame. A limit to excessive forward movement of the back support is provided by pairs of fixation plates positioned in aligned and abutting relationship on upper surfaces of each respective forward and rear ends of each spring member.

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 capable of increasing the supporting force, and still further includes a selector device for activating and deactivating the booster mechanism. The selector device is easily moveable with a low effort that is separated from and independent from any friction generated by internal components of the booster mechanism. In a narrower aspect, the control is powered, such as by an electrical or electromechanical device from a remote location. A back stop is attached to the selector device, for movement between a disengaged position, a partial-recline position, and a recline-prevented position.

Abstract: An office-type chair which provides for synchronous differential tilting of the seat and back assemblies, with the seat assembly being constructed such that the front lip thereof does not significantly lift upon rearward tilting. The chair incorporates a tilt control mechanism formed by a control body which secures to the upper end of the chair pedestal and an upright which pivotally connects to the control body about an axis disposed forwardly of the pedestal. A pivot assembly connects the upright and control body together.

Abstract: A chair comprises a seat support assembly including a seat support, the seat support assembly being adapted to stand on a surface so as to provide the seat support at a suitable height for a person to sit on, and a back support assembly, including a back frame member and a back support. In one embodiment, the back frame member has a curved middle portion substantially in the plane of the back support, and first and second end portions substantially in the plane of the seat support. The back frame member is flexibly interconnected to the seat support assembly by a first spring flexibly interconnecting the first end portion of the back frame member and the seat support assembly; and a second spring flexibly interconnecting the second end portion of the back frame and the seat support assembly.

Abstract: A vehicle seat structure having a one-piece flexible shell incorporated in the seating surface portion and a one-piece flexible shell incorporated in the backrest portion, wherein dampening means is provided between the shell and the seat frame for added comfort and vibration isolation.

Abstract: A furniture drive for displacing components of a piece of furniture is provided. An adjustment element is pivotably mounted on a main body and serves for displacing a component of a piece of furniture. A drive element is drivingly connected with the adjustment element for displacing the same. A lever gear mechanism is disposed between the drive element and the adjustment element for effecting the driving connection therebetween.

Abstract: A chair comprises a seat support assembly including a seat support, the seat support assembly being adapted to stand on a surface so as to provide the seat support at a suitable height for a person to sit on, and a back support assembly, including a back frame member and a back support. In one embodiment, the back frame member has a curved middle portion substantially in the plane of the back support, and first and second end portions substantially in the plane of the seat support. The back frame member is flexibly interconnected to the seat support assembly by a first spring flexibly interconnecting the first end portion of the back frame member and the seat support assembly; and a second spring flexibly interconnecting the second end portion of the back frame and the seat support assembly.

Abstract: A stackable chair includes a base with a pair of inverted U-shaped leg members. Each of the leg members includes a front leg portion, a rear leg portion, and a generally horizontal portion interconnecting the front and rear leg portions. The base also has a generally horizontal seat cushion frame extending between the U-shaped leg members with the transverse front spring reinforcement bar extending side-to-side. A back support frame has a generally vertical portion with an upper and lower end and a generally horizontal end portion that extends from the lower end. The generally horizontal portion includes a transverse rear spring reinforcement bar. A spring member has one end interconnected with the front spring reinforcement bar and another end interconnected with the rear spring reinforcement bar. The spring member supports the back support frame such that the back support frame has an unstressed position and a reclined position.

Abstract: A joint is provided that automatically pre-tensions itself during assembly. The joint includes first and second structural members, such as a back upright and a pivot link in a chair. A torsion spring bushing and a pair of threaded anchors pivotally connect the first structural member to the second structural member. The anchor and back upright include mating angled surfaces that inter-engage and rotate the torsion spring bushing during assembly in a manner that pre-tensions the spring bushing while engaging the anchors in a direction parallel an axis of rotation defined by the joint.

Abstract: A chair control actuator, such as a chair control paddle, is provided with a surface relief. The surface relief depicts a chair in two different positions illustrative of different chair positions which may result from use of said actuator. The surface relief has solid relief areas depicting a first of the two positions and outline relief areas depicting a second of the two positions.

Abstract: An upper back support in a vehicle seat, with the vehicle seat having a base assembly including a seat support. The seat member is supported on the base assembly and a back frame is pivoted to the base assembly for movement. A back shell is connected to the back frame and an upper back support is coupled to the back shell. The upper back support comprises a panel having a lower portion and an upper portion, with the lower portion flexibly coupled to the back shell of the vehicle seat. A resilient member is coupled to the panel proximate the upper portion and to the back shell of the vehicle seat. An additional resilient member can be coupled to the panel proximate the upper portion and to the back shell of the vehicle seat in a spaced apart relationship to the other resilient member.

Abstract: A stackable chair includes a base with a pair of inverted U-shaped leg members. Each of the leg members includes a front leg portion, a rear leg portion, and a generally horizontal portion interconnecting the front and rear leg portions. The base also has a generally horizontal seat cushion frame extending between the U-shaped leg members with the transverse front spring reinforcement bar extending side-to-side. A back support frame has a generally vertical portion with an upper and lower end and a generally horizontal end portion that extends from the lower end. The generally horizontal portion includes a transverse rear spring reinforcement bar. A spring member has one end interconnected with the front spring reinforcement bar and another end interconnected with the rear spring reinforcement bar. The spring member supports the back support frame such that the back support frame has an unstressed position and a reclined position.

Abstract: An upper back support in a vehicle seat, with the vehicle seat having a base assembly including a seat support. The seat member is supported on the base assembly and a back frame is pivoted to the base assembly for movement. A back shell is connected to the back frame and an upper back support is coupled to the back shell. The upper back support comprises a panel having a lower portion and an upper portion, with the lower portion flexibly coupled to the back shell of the vehicle seat. A resilient member is coupled to the panel proximate the upper portion and to the back shell of the vehicle seat. An additional resilient member can be coupled to the panel proximate the upper portion and to the back shell of the vehicle seat in a spaced apart relationship to the other resilient member.

Abstract: A stackable chair includes a base with a pair of inverted U-shaped leg members. Each of the leg members includes a front leg portion, a rear leg portion, and a generally horizontal portion interconnecting the front and rear leg portions. The base also has a generally horizontal seat cushion frame extending between the U-shaped leg members with the transverse front spring reinforcement bar extending side-to-side. A back support frame has a generally vertical portion with an upper and lower end and a generally horizontal portion that extends from the lower end. The generally horizontal portion includes a transverse rear spring reinforcement bar. A spring member has one end interconnected with the front spring reinforcement bar and another end interconnected with the rear spring reinforcement bar. The spring member supports the back support frame such that the back support frame has an unstressed position and a reclined position.

Abstract: A swivel arrangement is provided for a chair having a backrest, a chair seat, a chassis, and a base. The chassis includes a swivel seat mounted to an underside of the chair seat, a first connecting seat, a second connecting seat, a spring seat, a control device, and an adjusting rod. The swivel seat includes a hole and a stop adjacent to the hole. The control device includes a pressing plate engaged with an inner end of the adjusting rod and an operative block with a pressing portion. The first connecting seat, the swivel seat, and the second connecting seat are connected by axle rods.

Abstract: A chair comprises a back cushion material, a back plate and a back frame. The chair is used for looking at a display of a personal computer at suitable posture when it is reclined. The back plate comprises upper and lower shell which are connected by a flexible bent portion to each other. The back plate is mounted to the back frame at the upper end and a lower portion. When the chair is reclined, the upper shell is moved forwards and the lower shell is moved rearwards, so that an angle between the upper and lower shells may become smaller. Thus, the operator can take suitable posture for looking at the display any time.

Abstract: A chair control is provided for use with a chair having a base assembly including a base frame, a back frame pivoted to the base frame for movement between upright and reclined positions, and a seat slidably supported on the base frame and pivoted to the back frame so that the seat moves forwardly and its rear moves forwardly and downwardly with the back frame upon recline. The chair control includes a novel energy mechanism comprising a control housing, a transverse spring positioned transversely in the housing, and a lever pivotally engaging a side of the housing to form a fulcrum with one end of the lever engaging the spring and another end of the lever engaging a synchronized seat and back arrangement. A moment arm shift adjuster is provided for adjusting the spring tension on the back frame. The moment arm shift adjuster is readily adjustable and includes an overtorque device to prevent damage to components of the energy mechanism.

Abstract: A chair with user responsive reclinable back-support connected to a seat member by a set of elastically deformable bracket members. A pivot axis defined by an imaginary line connecting the respective center-of-curvature of the bracket members is positionable in substantial correspondence with the chair occupant's hip joint and is selectively displaceable under occupant loading for reclining the back-support.

Abstract: A tilt control apparatus is provided for use on a chair having a base and a backrest, and includes a center retainer from which a pair of torsion bar segments protrude. A tubular outer casing is received over each torsion bar segment and is affixed to the center retainer, and an end bar retainer is received on the distal end of each torsion bar segment for rotation therewith. A structure is provided for restricting axial and rotational movement of the end retainers relative to the outer casings, holding the end retainers in place on the apparatus and permitting the torsion bar segments to be pre-torqued, if desired.

Abstract: A task chair is provided having a base frame, a back assembly pivoted to the base assembly for movement between upright and reclined positions, and a seat slidably supported on the base assembly and pivoted to the back frame so that the seat moves forwardly and its rear moves forwardly and downwardly with the back frame upon recline. The pivots for connecting the back frame to the base frame and for connecting the seat to the back frame permit quick fastenerless assembly by flexing the back frame during assembly. The pivots include rubber elements that permit flexing of a bearing element to prevent binding during rotation when the bearing element is not fully aligned with a pivot axis. A method of assembly including flexing apart the configured end sections of the back frame positioning the configured ends adjacent opposite sides of the seat, and releasing the configured end sections so that they engage the seat, is also disclosed.

Abstract: A chair, with an elastic movable means capable of allowing the back of the chair to be leaned back at an angle of inclination, is disclosed. The chair has one or more leg frames. A seat frame is mounted to the top portion of the leg frames and holds a seat. A back frame is connected to the seat frame and holds a back. The elastic movable means is provided at the junction between the seat and back frames and allows the back frame to be elastically leaned back relative to the seat frame. The elastic movable means has two leaning angle limit units at both ends and one torsion bar extending between the two limit units. Each of the two limit units is fitted into the seat and back frames at opposite ends and limits the leaning angle of the back frame. The torsion bar elastically returns the back frame from a leaned position to the original position.

Abstract: A pivotable fastening for a chair, includes fastening members as well as a resilient element allowing resilient displacement of the fastening members The fasting has two substantially identical fastening members one of which has a, and delete the remainder of the line said fastening members (2A) comprising a first cup-shaped pivotable portion having first protruding stoppers. The second fastening member has a second corresponding cup-shaped pivotable portion having second protruding stoppers both fastening members encircle a string-shaped elastic element extending through both fastening member.

Abstract: A chair has a base, a generally horizontal seat supported on the base, and a generally vertical back supported on the base behind the seat and provided at a predetermined spacing above the seat with a horizontally extending flex joint having formations for permitting free pivoting backward of an upper portion of the back to a predetermined backwardly deflected position and for thereafter resisting further backward deflection. The back comprises a front plate, a cushion carried on the front plate, and a rear plate fixed to the front plate and formed with the flex joint. The formations include a pair of extending flanges extending generally horizontally from the rear plate and a bight interconnecting the two flanges. The flex joint can be unitarily formed with the rear plate. Its flanges are vertically spaced from each other and only touch when the predetermined backwardly deflected position is reached.

Abstract: A chair with a pivoting backrest includes resilient leaves which cooperate with limbs for supporting the backrest to oppose the pivoting of the backrest towards its pivoted-back position.

Abstract: A chair has two lateral frame parts, each one in the form of a single, continuous member of an elastically yielding material. Transverse rods are connected between the lateral frame parts. A seat is connected to at least one of the transverse rods and a back rest is connected to at least one of the transverse rods. The single member of the lateral frame parts is preferably made of spring steel. Connecting elements that are slipped onto the lateral frame parts are used for connecting the transverse rods to the lateral frame parts. The connecting parts can be balls having throughbores for receiving the lateral frame parts and threaded holes, extending substantially perpendicularly to the throughbores, for receiving the transverse rods.

Abstract: A chair is provided which comprises a support, a seat arranged above the support, and a seat back tiltably connected to the support behind the seat. The seat back has an upper back supporting portion and a lower waist supporting portion. The chair further comprises a mechanism for deforming the waist supporting portion forward until the seat back tilts rearward to a predetermined intermediate tilt angle but for retarding or stopping such forward deformation when the seat back tilts rearward beyond this intermediate tilt angle. The seat may be made to move rearward as the seat back tilts rearward.

Abstract: A durable patient chair (10) comprises a chair base frame (12) including a pair of substantially rigid, spaced apart, front legs (22); a pair of brackets (14), each bracket (14) being fixedly attached to each front leg (22) and has a downwardly extending lip (42) and a horizontal portion (44); a rearwardly extending resilient seat (16) having a front edge with a downwardly extending lip (56) for attachment to the brackets (14); and a pair of first fasteners (18) for attaching the downwardly extending lip (42) of the bracket (14) to the downwardly extending lip (56) of the seat. Preferably, a second fastener (20) is used for attaching the horizontal portion (44) of the bracket (14) to an outer surface of the seat (16) proximate to the front edge (53) to better secure the seat (16) to the bracket (14).

Abstract: A one-piece seat shell having a backrest and a seat connected by an angled transition section that contains a plurality of slots to permit resilient deflection of the backrest with respect to the seat.

Abstract: A chair control includes a flexible truss having tandem springs interconnected in spaced relation so that they interact to provide a unique torque versus displacement profile during flexing, with a portion of one of the springs moving longitudinally relative to a portion of the other spring as they are flexed. A stop on the springs limits the longitudinal movement, thereby limiting the angle of tilt both in the upright and rearward chair back positions. In one form, the springs are pairs of leaf springs connected in tandem and operably attached to a chair back and bottom formed by a corrugated member. In another form, one of the springs is a flexible shell forming a chair with the other spring attached thereto in a nested arrangement. In yet another form, the flexible truss is a separate module installable in furniture as a self-contained energy absorber.

Abstract: A chair having a seat section, a base section and a support structure interconnecting the seat and base sections for rockably supporting the seat section relative to the base section is disclosed. The support structure includes a resilient member that is generally W-shaped, as viewed in plan, and generally U-shaped, as viewed in elevation. The resilient member includes first and second transversely spaced outer legs fastened to the seat section, and first and second inner legs positioned intermediate the first and second outer legs, when viewed in plan. The inner legs are fastened to the base section. In the preferred embodiment the base section includes upper and lower portions which are pivotable relative to one another. In this case the first and second inner legs are fastened to the upper portion of the base section so that the seat section may be swiveled relative to the lower portion of the base section.

Abstract: The present invention is directed to a suspension mechanism (10) utilized to interconnect the seating portion (16) as well as the back supporting portion (18) of a chair assembly (12) to a pedestal assembly (14). A spring support (30) is fastened to the upper end portion of the pedestal assembly (14). At least one primary seat spring (40) is secured to the spring support (30) and extends generally upwardly and rearwardly therefrom to be secured to the underside of a seating portion (16). Preferably, the primary seat spring (40) comprises a pair of laterally spaced, leaf springs (40). Also secured to the spring support (30), and preferably between the pair of laterally spaced primary seat springs (40), is an interactive spring (60). The interactive spring (60) extends outwardly from the spring support (30) in generally parallel relation with the primary seat springs (40) to be disposed in a cantilevered fashion therebetween.

Abstract: Chair having seat and back parts capable of springy tilting relative to each other. The seat and back parts are provided in the region where they join each other with a reduced width to intensify the relative tilting thereof. Longitudinal slots are also provided in the seat and extend from the region of reduced width to further intensify this relative tilting.The chair frame is provided with fastening elements in the region of the front edge of the seat for tilting attachment of seat and back.

Abstract: There is described a vehicle seat, notably for motor vehicle, comprising a bottom and a back, that back portion at least whereagainst the back of a person taking place in the seat bears, so cooperating with resilient members as to be swingable about a fixed point relative to the bottom, exclusively with an up-and-down motion, which seat is provided with means to limit conveying from the seat bottom, vibrations with a frequency higher than 10 Hz to that back portion whereagainst said person back does bear.

Abstract: A frame assembly for a chair includes a base member, a seat support member and a backrest member. The front end of the seat support member is pivotally mounted on the front end of the base member a seat suspension spring is provided for the purposes of urging the seat support member to its elevated position. The seat suspension spring is mounted at a point spaced a substantial distance from the pivotal connection between the base and the seat support. Preferably, the suspension spring is a compression spring mounted rearwardly of and extending longitudinally of the backrest member so as to enjoy a substantial mechanical advantage.

Abstract: The present invention discloses a chair having a seat and a backrest which is hinged to the seat by a resilient hinge. The hinge is substantially moulded together with the shell formed by the seat and backrest. The degree of flexure of the backrest exceeds any flexure of prior art. One piece plastic shells and stops are preferably provided to limit the degree of flexure of the hinge. Moulding the hinge with the shell substantially reduces costs.

Abstract: A seat for a vehicle, preferably a motor vehicle, includes a bottom and a back. The back of a passenger bears against the back of the seat. The back of the seat is mounted to swing together with the back of the passenger in a vertical direction. The seat back has a natural frequency which is higher than the natural frequency of the seat bottom when bearing a passenger.

Abstract: An adjustable chair is described comprising a body supported by a base and having a frame constituted by two parts and hingedly connected together.The main characteristic of the present invention lies in the fact that it includes a mechanism having a first body hinged about a pin rigidly connected to the base and having its front end rigidly connected to the part associated with the seat, and a second body and having a rear end fixed to the part associated with the seat back and a front end connected, by spring means, to a central portion of the said first body.

Abstract: The seat furniture is provided with a seat-plate backrest inclination-adjusting mechanism (6), a single-column supporting device (2) and a supporting foot (1). The backrest is composed of a backrest bottom part (16) and a backrest top part (14), and when the backrest inclination is fixed the backrest top part (14) can additionally be moved, counter to the pressure exerted by a restoring-spring arrangement (13), so as to swing freely to the rear between a first and a second stop position of an adjusting-spring device (22).

Abstract: A resilient hinge comprising a first support that can be mounted on a member to be supported, such as the back of a chair, and a second support that can be mounted on a main body, such as the remainder of a chair, wherein the two supports are each connected hingedly to a hood and wherein between each support and the hood two bodies of elastic, resilient material are arranged.

Abstract: An ergonomic chair comprising:a substantially rigid seat structure (2,2'),a substantially rigid back structure (1,1'), articulated to the seat structure,a base (5,5') resting on the floor,a legs structure comprising on each side a pair of crossing legs (3,3', 4,4'), one (4,4') of which is articulated at the upper end to the front portion of the seat structure (2,2'), is provided with a slider (8,8') for the other leg (3,3') and is bound at the lower end to the base (5,5'), whereas the other leg (3,3'), which is elastically bending deformable, is articulated at the upper end to the back structure (1,1'), leans against a back stud (9,9') applied to the seat structure (2,2') engages with the slider (8,8') foreseen in the other leg (4,4') and is bound at the lower end to the base (5,5').