Abstract: A therapeutic back support device including a back support portion that automatically and repeatedly moves forward to maintain engagement with a user's back as the user moves forward with respect to a chair seat. The back support portion substantially resists backward motion and provides substantially continuous therapeutic support to the user's spine pending a release signal.

Abstract: A therapeutic back support device including a back support portion that automatically and repeatedly moves forward to maintain engagement with a user's back as the user moves forward with respect to a chair seat. The back support portion substantially resists backward motion and provides substantially continuous therapeutic support to the user's spine pending a release signal.

Abstract: A chair is provided that is designed so that the angle of the seat surface portion and the angle of the back surface portion are independent of each other and change, and a user can always take the optimum seated posture. The chair includes a base portion, a first link fixed to a seat and rotatably connected to the base portion, and a second link fixed to a seat back rest and rotatably connected to the first link. The chair also includes a first torque-generating mechanism that generates torque in accordance with the angle of the first link relative to the base portion; and a second torque-generating mechanism that generates torque in accordance with the angle of the second link relative to the first link.

Abstract: A chair according to embodiments of the present invention includes a base; a first linkage pivotably coupled to the base, a seat pivotably coupled to the first linkage, a second linkage pivotably coupled to the seat and pivotably coupled to the base, a back comprising a substantially upright portion and an attachment portion, the attachment portion pivotably coupled to the base at a first pivot point, and a third linkage pivotably coupled to the back at a second pivot point and pivotably coupled to the second linkage, wherein the second pivot point is on the attachment portion between the first pivot point and the substantially upright portion.

Abstract: It is a subject to provide a chair capable of realizing a condition in which movements of a seating person are preferably followed and a condition in which a back of the seating person can be preferably supported. For this purpose, a chair C comprising a lower frame portion that is supported to be rockable between a standing position and a rearward tilting position of a back frame with respect to the base and an upper frame portion that is supported to be rockable between a normal position and a rear end position, wherein the chair is further comprised with a movement range setting mechanism with which a movement range through the rocking movement of the upper frame portion with respect to the lower frame portion is made changeable in accordance with the position of the lower frame portion with respect to the base during the rocking movement.

Abstract: A chair has a coupling mechanism between a seat and a back, which includes a joining member, and a coupling member; the seat has two opposite front and two opposite rear ears on a bottom; the joining member is secured on a supporting tube for the seat, and has two opposite sloping slots on each end, and intermediate adjustment slots; the connecting member has a front fixing hole, and a rear sloping slot; the joining member, the connecting member, and the seat are joined together with a first shaft passed through the front ears and the front sloping slots, with a second shaft passed through the rear ears and all of the rear sloping slots; a third shaft is passed through the adjustment slots and the fixing hole; the connecting member is further pivoted to the joining member at a middle portion; the back is joined to the connecting member.

Abstract: A seating unit includes a base with a control housing, a back supported on the base for reclining movement, and a seat supported at least partially by a pivoting link on the base for synchronous movement with the back upon recline of the back. A back stop is operably mounted on a pair of parallel guide rods that extend transversely across the control housing for selective movement to a plurality of different positions where the back stop engages the link to limit movement of the seat and hence limit recline of the back to a plurality of selectable recline positions corresponding to the plurality of different positions.

Abstract: The invention provides a chair that the switching between operation and fixation of rocking may be operated with the height adjustment of the chair by one operation lever. A resilient member is interposed between a seat frame whose height is adjustable by a cylinder and a back frame rotatably fitted to the seat frame, wherein a joint member is rotatably fitted to the seat frame with a vertical shaft, an operation lever led to the outside of the seat frame and a pressing piece which touches and leaves a button for rod advancing and retreating of the cylinder are provided with a rocking member which is rockably assembled to the joint member with a horizontal shaft, and an interlocking regulating member is attached to an arm piece of the joint member so that the rotation of the back frame may be adjusted by moving the regulating member.

Abstract: A chair adjustable device includes a base with which a seat frame and a backrest frame are respectively and pivotably connected. A positioning mechanism is connected to the base and includes an operation handle which is able to shift a transmission frame and a positioning plate is movably connected to the transmission frame and biased by a spring, so that the positioning plate can be movably engaged with one of notches defined in a positioning member on the seat frame. The seat frame and the backrest frame are connected by a connection member so that the chair can be adjusted its tilt angle by operating the operation handle.

Abstract: A reclining apparatus includes a base, a reclining element and a control element. The base is arranged between a seat and a post of a chair. The reclining element is connected to a backrest of the chair and pivotally installed on the base. The reclining element defines a series of apertures. The control element is installed on the base so that the control element is moved on the base while it is rotated on the base. The control element includes a tip for removable insertion into one of the series of apertures defined by the reclining element, thus retaining the backrest on a selected one of several angular positions on the seat.

Abstract: Cushioning device to cushion a backrest with respect to the seat of a chair or suchlike. The device comprises a first supporting element connected to the backrest, a second supporting element connected to the seat and pinned to the first supporting element, and a spring connected both to the first supporting element and to the second supporting element, to allow a reciprocal elastic oscillation, of a determined amplitude, between the backrest, which can oscillate, and the seat, which remain still. In a wall of the first supporting element a lodging seat is provided to lodge, at least partially, the spring in such a manner that the longitudinal axis of the spring is substantially aligned with respect to the first supporting element.

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 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: A chair control mechanism for positioning between the seat and seat support of a chair. The chair control mechanism includes a base section for mounting to a seat support such as an adjustable height cylinder, and a seat mounting section pivotally interconnected with the base section. A seat is mounted to the seat mounting section, and is pivotal about a seat pivot axis. An adjustable position back mounting arrangement is pivotally interconnected with the seat mounting section, and the chair back is engageable with the back mounting section. A variable stop arrangement is interposed between the base section and the seat mounting section, for varying the range of pivoting movement of the seat relative to the seat support. The back can be selectively locked in one of a number of predetermined positions relative to the seat by operation of a variable position back locking arrangement.

Abstract: A chair control mechanism for positioning between the seat and seat support of a chair. The chair control mechanism includes a base section for mounting to a seat support such as an adjustable height cylinder, and a seat mounting section pivotably interconnected with the base section. A seat is mounted to the seat mounting section, and is pivotable about a seat pivot axis. An adjustable position back mounting arrangement is pivotably interconnected with the seat mounting section, and the chair back is engageable with the back mounting section. A variable stop arrangement is interposed between the base section and the seat mounting section, for varying the range of pivoting movement of the seat relative to the seat support. The back can be selectively locked in one of a number of predetermined positions relative to the seat by operation of a variable position back locking arrangement.

Abstract: A chair including a seat assembly having an improved seat spring system to provide a flexible spring backrest frame. A pair of ends of spaced apart backrest frame members are arranged in registry with respective ends of seat support frame members, with each end positioned in spaced apart alignment across a gap from the respective end of each frame member. An elongated shaped flexible spring element spans each gap, with each spring element having opposed ends being extended a distance along each frame member from the gap. Each opposed end is restrained by a first and a second elongated U-shaped holder receptor paired and separately attachable to each opposed end of the spring element. Each holder receptor includes an opening end being faced towards and in alignment with the second holder opening end. The spring element is positioned between each opening end in side-by-side orientation beside the frame members, providing controlled angular range of motion of the backrest frame when moved by a chair occupant.

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 seat adjustment mechanism for a chair includes a first handle which controls the height of the seat above a surface supporting the chair. A second handle allows the user to selectively lock the seat at a user selected angle relative to the supporting surface. As the seat is tilted into a desired position, the seat adjustment mechanism provides limited horizontal and vertical movement of the seat to maintain the chair in an ergonomically correct position. The mechanism includes a housing or enclosure adapted for connection to a pedestal, and a seat bracket for mounting to the underside of the seat. An intermediate bracket is pivotably mounted to the lower enclosure. One end of the seat mounting bracket is pivotably connected to an end of the intermediate bracket, and the other end of the seat bracket is interconnected with the lower enclosure via a link arrangement.