Abstract: A rocking chair includes a seat, a backrest that is tiltable rearward, a locking spring portion that imparts resistance to the rearward tilting of the backrest, and a resilience adjustment member that changes the degree of resistance of the spring portion to the rearward tilting of the backrest. The resilience adjustment member is a cam that is rotationally operable by a person seated on a seat and the position in which rocking load due to the rearward tilting of the backrest is applied to the spring portion is changed by the cam, so that moment applied to the spring portion changes and the degree of resistance of the spring portion is adjusted.

Abstract: A chair chassis includes a base, a warped plate, a first adjustment member and a second adjustment member. The base including an upper cover, a lower cover and a front cover is arranged at a bottom surface of a seat of a chair. The warped plate is disposed under the upper cover of the base for connecting to a seat back of the chair. Two compression springs arranged in parallel with a certain interval are disposed between the first adjustment member and the warped plate for adjusting travel distance of the compression springs and changing a force of the seat back. The second adjustment member is used for lifting the chair by rotation of a second adjustment shaft. The chair chassis is fastened and adjusted by operating the second adjustment shaft to move along an axial direction. The chair chassis has simple structure, easy operation and improved applicability.

Abstract: The invention relates to a mechanism (2) designed for a chair, in particular for a rotatable office chair having a gas spring (12) vertically arranged in the underframe (1), the gas spring having a telescopically extendible piston rod so that the height of the seat (9) can be adjusted. The tilting adjustment of the seat (9) between the rest position (S0) and the relaxation position (Smax) occurs in synchronization with the adjustment of the backrest (96) between a rest position (R0) and a relaxation position (Rmax) inclined backward. The mechanism (2) has a shell (30), through which a stationary first rotational axis (D1) extends and on which a seat carrier (80) capable of being inclined is mounted.

Abstract: A rocking chair includes a seat, a backrest that is tiltable rearward, a locking spring portion that imparts resistance to the rearward tilting of the backrest, and a resilience adjustment member that changes the degree of resistance of the spring portion to the rearward tilting of the backrest. The resilience adjustment member is a cam that is rotationally operable by a person seated on a seat and the position in which rocking load due to the rearward tilting of the backrest is applied to the spring portion is changed by the cam, so that moment applied to the spring portion changes and the degree of resistance of the spring portion is adjusted.

Abstract: A chair includes a chair body, a connecting member, a back portion, and a restoring device. The chair body includes a base having a receiving chamber. The restoring device includes a threaded adjusting sleeve rotatably mounted in the receiving chamber, a threaded rod screwed into the adjusting sleeve, a pull cord having a first end mounted on the connecting member and a second end mounted on the threaded rod, and an elastic member biased between the base and the adjusting sleeve. Thus, when the back portion is pressed, the connecting member is driven to pivot about the chair body so that the back portion is moved to adjust its inclined angle. In addition, the elastic member provides a damping force to damp a further movement of the back portion to limit the inclined angle of the back portion.

Abstract: An adjusting mechanism is used to adjust a restoring force that acts on a backrest of a chair. The adjusting mechanism has a spring element for creating the restoring force, a support, and a backrest support that is pivotably mounted about a support axis on the support. An adjusting element configured as a pair of scissors containing a first scissor arm and a second scissor arm is provided, and the scissor arms are rotatably connected to each other about a scissor axis. The first scissor arm is pivotably mounted on the backrest support about an adjusting axis. A spring force produced by the spring element acts on the second scissor arm. A first actuating lever length is defined between the support axis and the scissor axis. The lever length is changeable using an adjusting element for adjusting the restoring force by pivoting the adjusting element about the adjusting axis.

Abstract: A multi-section angle adjusting structure for a chair back contains a supporting member axially connected to a base and axially inserted to a sliding groove through a shaft to slide in the sliding groove so that the chair back fixed to the supporting member is adjusted to a desired angle relative to the base. The shaft includes a slidable bar fitted thereon to be connected to a slot of the base. Another end of the slot pushes a toothed block biased against by a first spring which contacts with a stop plate so that the toothed block abuts against an end portion of the slidable bar. The slot includes a positioning structure mounted therein, and the positioning structure includes a toothed seat guided by a guiding line to engage with the toothed block.

Abstract: A mechanism for an office chair having a backrest support which may be pivoted rearwardly. Adjustment of the backrest pivotal motion is accomplished by the mechanism having a base support which may be positioned on a chair column, a seat support, the backrest support which may be pivoted to the rear, and a pre-tensioned spring arrangement for enabling the mechanism to counter or oppose the movement of the backrest support. The seat support and the base support form a movable unit, which may be moved relative to the chair column depending on the weight of a user applying a load to the seat support. Movement of the movable unit causes an adjustment of the pre-tension of the spring arrangement and/or an adjustment of the spring constant of the spring arrangement.

Abstract: A tilting fitting device enables a chair seat to be tiltable forwards and backwards against spring force of tilt-resisting springs, the tilting fitting having an upper part that is fastenable to the chair seat and a lower part that is fastenable to a chair base and tiltably connected to the upper part, wherein the tilting resistance is adjustable by adjusting spacing between the tilt-resisting springs and distance of each spring from a respective side of a tilting axis for the upper part. An actuating element is arranged for simultaneous engagement with two support members, an actuating element, along a part of each of its two sides in the element's direction of motion. On movement of the actuating element in the longitudinal direction of the tilting axis, it is adapted to cause rotation of the support members and springs mounted thereon, thereby changing the spacing of the springs.

Abstract: A device for adjusting the reclining force in office chair mechanisms comprising at least two mutually hinged parts and elastic means (16) which maintain said parts elastically spaced apart, said device being characterized by comprising:—at least two levers (7, 6), at least one of which interacts with said elastic means (16) and the other of which is connected to one of said hinged parts, said levers respectively interacting via at least one movable contact element (13) by way of contact surfaces,—means (9, 10, 14) for adjusting the position of said movable contact element (13) such as to modify the points at which said movable contact element bears on said contact surfaces and consequently such as to modify the lever arms.

Abstract: An adaptive energy absorption system for a vehicle seat is disclosed, utilizing an adaptive energy absorber or variable profile energy absorber (VPEA) for mitigating occupant injury due to extreme vehicle movement (e.g., during a vehicle shock event), and/or for mitigating vibration experienced by an occupant of the vehicle seat during normal vehicle operating conditions. The adaptive energy absorption system achieves the aforementioned objectives for a wide range of occupant weights and load levels. Various configurations of dual-goal energy absorption apparatuses that enable both shock mitigation and vibration isolation are disclosed.

Abstract: A tilt mechanism for a chair includes rotary stop means defining a plurality of selectable tilted positions of the chair seat/back. In another aspect, an anti kick-back feature is provided based. The mechanism includes upper and lower housing parts and a cushioning spring that normally maintains the parts in a rest position with respect to one another while allowing the mechanism to tilt. A further aspect of the invention provides an improved spring tension control that allows the spring to be installed and removed in a fully relaxed condition so that no special tools are required.

Abstract: A chair assembly has a chassis connected between a backrest frame and a pneumatic foot rod. The backrest frame has a pivotal hole and has an elongated slot to receive a sliding pivotal rod pushed by a spring so that the backrest frame is controlled by the sliding pivotal rod when the backrest frame pivotally moves relative to the chassis. Because the incline of backrest frame is controlled by an adjusting wheel pushing the spring and because the seat frame has a rocking board to support the backrest frame, the chair assembly is able to change the inclined angles of the backrest frame. Moreover, the seat frame has a sliding base for attaching a pad. Thereby, the chair assembly has adjustable functions.

Abstract: A chair (1), in particular a swivel office chair, is provided with a bottom chair part (2) having a column (3), a seat support (4) held on the bottom chair part (2), a seat (6) connected pivotably to the support, and a backrest support (5) holding a backrest (7) and connected pivotably to the seat support (4). The movement of the seat (6) is coupled with the movement of the backrest support (5) by a synchronizing mechanism having at least one spring (10) and coupling elements. The synchronizing mechanism is arranged essentially within the column (3).

Abstract: An office chair having a resilience tilt-adjusted device of a backrest includes an upper and a lower casing put together to cover an elastic adjuster which can press one end of elastic members with difference forces. Another end of the elastic members leans against an axle rod which is disposed at the lower end of the backrest supporter. The two ends of the axle rod pass through the casing. The lower end of the backrest is pivotally connected to a predetermined area within the casing as a pivot for swinging. A positioning rod having a rack is passed through the center of the axle rod so as to insert the rack onto the guiding groove of the casing. A positioning piece is arranged upon the rack and can be controlled to move up and down for inserting its end into the rack. Therefore, when the positioning piece is inserted into or exited from the rack, the backrest supporter can be positioned in a desirable angle after tilting.

Abstract: A biasing element assembly for an article of furniture includes an actuation mechanism to enable a leg rest assembly to move between a stowed position and an extended position and be retained in intermediate positions. The mechanism includes a support shaft, a drive rod spaced apart from the support shaft, and a toggle link coupled to the drive shaft. Multiple apertures are aligned on the toggle link. The biasing element assembly includes a single biasing element having first and second ends. The first end is connected to one of the toggle link apertures. The biasing element second end is a hook that slides along the support shaft. A biasing element spring tension is varied by engaging the first end to different ones of the toggle link apertures. The biasing element slides to align itself on the support shaft where a biasing element length is minimized.

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 cam wedge which supports the legs of a pair of coil springs and a cooperating drive block assembly which cooperates with the cam wedge to drive the cam wedge upwardly and downwardly to vary the tilt tension. The drive assembly includes drive blocks mounted on a threaded shaft which are displaceable sidewardly toward and away from each other to either drive the cam wedge upwardly when the drive blocks move together or downwardly when the drive blocks move away from each other.

Abstract: A tilt mechanism for an office chair includes a spring tension control that incorporates a wedge arrangement including a moveable wedge component that is displaceable laterally by turning a control knob below the seat of the chair, to force fixed wedge components apart and increase the spring tension. Turning the knob in the opposite direction reduces spring tension.

Abstract: The chair includes seat and back assemblies interconnected in a four-bar linkage. The chair further includes a tension mechanism comprising a coil spring projecting forwardly from a base and an adjustment linkage which is connected to said coil spring and to a front link of said four-bar linkage. A back linkage end of said adjustment linkage being axially movable along an axis of said coil spring and a front linkage end being vertically movable along said front link to adjust displacement of said adjustment linkage during rearward pivoting of said front link.

Abstract: A locking device in an office chair structure of the type with articulation permitting the movement of the adjustable seat and seat back, with a mobile base from which a column rises, which is adjustable in height, and which supports a seat plane and a hinged seat back. The structure of the office chair includes a seat, attached at the front to the corresponding front side of a central support body secured to the top of the adjustable column along the vertical axis; a central support body, which, at the back, keeps in place the lower ends of the two support uprights of the armrests and a seat back connected to the seat, swinging and linked, near to the back part, to the central support body by means of a compression spring; Coaxially to the compression spring, there is a rod, one side of which is integral with the back rest, while the other side is axially mobile with respect to a static connecting body linked to the central support body of the chair.

Abstract: A working chair with adjustable backrest support pre-set tension is described, in which a swiveling backrest support is positioned on a seat part, the backrest support being prestressed against the back of the user with a manually adjustable pre-set tension of an energy storing device. The front end of the energy storing device is rotatably mounted on a free, swiveling end of a guide bar close to the seat edge, and the rear end of the energy storing device is coupled to a free, swiveling end of the backrest support at a contact point which is designed to be adjustable and detectable.

Abstract: A support for tilting or synchronized chair is provided. The device includes a supporting frame, a mobile frame, an elastic member, a stiffness adjustment mechanism coupled with the elastic member, a locking mechanism for engaging the mobile frame with the supporting frame, and an actuation device for engaging and disengaging the locking mechanism. The actuation device includes a rocker arm and a return arm. The return arm is connected to the end of the rocker arm that the locking mechanism is attached. The rocker arm has at least two positions of stable equilibrium that are determined by the engagement or disengagement of the locking mechanism. An alternative embodiment includes an outer shell having first and second pins that are coupled with the backrest frame. The second pin may be positioned within a slot formed in the shell so that the backrest frame may move between upright and reclined positions.

Abstract: A chair comprises a seat support with a front seat support part and a rear seat support part which is connected thereto via a pivoting axis. An adjustable length energy storing device serves for adjustment relative to each other of the seat support parts. The energy storing device is pivotably supported on the seat support parts at a distance from the pivoting axis. This distance can be modified by means of an adjusting element by operation of a turning handle. The turning handle is connected to the adjusting element via a coupling element, with the axes of rotation of the adjusting element and turning handle not being in alignment. This ensures conveniently accessible modification of the adjusting force of the energy storing device.

Abstract: A chair, in particular an office chair, comprising: a base structure, a seat support structure, articulated to the base structure around a transverse axis, an adjustable elastic device to apply an elastic force between the base structure and the seat support structure, a manually operated adjustment device for varying the distance between said adjustable elastic device and said transverse axis.

Abstract: A seating unit for supporting a body or part of a body comprises a base part and at least one supporting part for supporting the body or part of the body. The supporting part is situated or can be placed in a set nominal height position relative to the base part. In addition, the supporting part is movable at least in the vertical direction over a certain movement range relative to the nominal height position, in such a way that within this movement range the supporting part can take up various positions of equilibrium when there is a certain weight on the supporting part.

Abstract: A synchronizing mechanism for office chairs comprises a base carrier, a backrest carrier, and a seat carrier, which are coupled to one another via corresponding joints. A spring arrangement to actuate the synchronizing mechanism consists essentially of helical compression springs disposed parallel to the longitudinal seat direction flat underneath the seat carrier, wherein for each helical compression spring a counter-bearing extension arm is provided, a front end of which is articulated to the base carrier and a rear-facing end of which, freely projecting, forms a counter bearing for a rear support of the helical compression spring, and wherein the at least one helical compression spring is supported in each case with its front end on a counter bearing formed on the seat carrier.

Abstract: A chair comprises a seat support with a front seat support part and a rear seat support part which is connected thereto via a pivoting axis. An adjustable length energy storing device serves for adjustment relative to each other of the seat support parts. The energy storing device is pivotably supported on the seat support parts at a distance from the pivoting axis. This distance can be modified by means of an adjusting element by operation of a turning handle. The turning handle is connected to the adjusting element via a coupling element, with the axes of rotation of the adjusting element and turning handle not being in alignment. This ensures conveniently accessible modification of the adjusting force of the energy storing device.

Abstract: A synchronizing mechanism for office chairs comprises a base carrier, a backrest carrier, and a seat carrier, which are coupled to one another via corresponding joints. A spring arrangement to actuate the synchronizing mechanism consists essentially of helical compression springs disposed parallel to the longitudinal seat direction flat underneath the seat carrier, wherein for each helical compression spring a counter-bearing extension arm is provided, a front end of which is articulated to the base carrier and a rear-facing end of which, freely projecting, forms a counter bearing for a rear support of the helical compression spring, and wherein the at least one helical compression spring is supported in each case with its front end on a counter bearing formed on the seat carrier.

Abstract: A device for adjusting the compression force of the spring in an articulation of a seat of the type equipped with a mobile “rocket launcher”-type base, from which base there rises a column, adjustable in height, which supports a reciprocally hinged seat plane and a seat back, whereby the seat back supports a headrest and a lumbar support that is also adjustable, whereby:

Abstract: This and other purposes are fulfilled by the present innovation, according to the characteristics of which in the annexed claims, it solves the problems indicated above by means of a locking device in an office chair structure of the type with articulation permitting the movement of the adjustable seat and seat back, with a mobile base from which a column rises, which is adjustable in height, and which supports a seat plane and a hinged seat back, whereby the structure of the office chair consists of:

Abstract: It is provided for a reclining device for chairs and the chair with said reclining device, comprising an elastic element with linear strain (8) having a first end (8a) abutting against the primary body (2) of a chair, and a half-shell element (12) adapted to house at least a portion of the elastic element (8) starting from a second end (8b) of the latter, said half-shell element (12) having two abutment portions (12b) for a pair of pushing extensions (13) integral with the support element (4) of the reclining back.

Abstract: The chair comprises an axis X1 that extends right and left and that connects a seat 6 and a supporting body 3 arranged under the seat 6 in a rotatable manner at a front end portion of the seat frame 4, an axis X2 that connects the seat 6 and a backrest 7 in a rotatable manner at a rear side to the axis X1 and an axis X3 that connects the backrest 7 and the supporting body 3 in a rotatable manner, and the seat and the backrest are made to make a rocking movement between an upright posture and a rearward tilted posture with synchronizing the seat and the backrest by adopting an arrangement of a sliding engagement structure to a supporting portion of the axis, and the chair is also provided with a restraining member B1 to restrain a sliding range of the axis X1 variably by directly working the axis X1 to be restrained, an operating member B2 to operate the restraining member B1, a transmitting axis B3 to transmit an operating force of the transmitting member B2 to the restraining member B1 and a click stop mecha

Abstract: A reclining chair including a support base, a chair seat rotatably coupled at its forward portion to the support base, a substantially vertically disposed coil spring provided adjacent the forward portion of the seat and between the seat and the support base such that the coil spring is pivotally coupled to the seat portion and the support base at its ends, an apparatus for pivoting one end of the coil spring about another end of the coil spring and an offset crank for driving said apparatus.

Abstract: A chair control providing both articulating tilt motion and dual-ratio, adjustable, synchronized tilt motion. In a first aspect, the control can be configured as either an articulating tilt control or a synchronized tilt control. In a second aspect, the angle between the seat and the backrest may be selected by the user when the control is configured for either the articulating mode or the synchronized mode. In a third aspect, when in the synchronized mode, the angle between the seat and the backrest increases during forward tilt action to avoid “clam shelling.” In a fourth aspect, a forward tilt selector enables or prohibits forward tilting of the control.

Abstract: A reclining chair including a support base, a chair seat rotatably coupled at its forward portion to the support base, a substantially vertically disposed coil spring provided adjacent the forward portion of the seat and between the seat and the support base such that the coil spring is pivotally coupled to the seat portion and the support base at its ends, an apparatus for pivoting one end of the coil spring about another end of the coil spring and an offset crank for driving said apparatus.

Abstract: A seating unit is provided having a base assembly, a back frame 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. A flexible back is connected to the back frame at top and bottom locations and is provided with lumbar adjustment for improved lumbar force/support and shape. A seat is provided with seat depth adjustment and with active and passive thigh flex support. The seat includes a front section adjustably and/or flexibly supported on a rear section for optimal comfort while supporting a seated adult user's thighs, With the rear section being configured to carry a majority of the weight of a typical seated adult user. A novel energy mechanism is provided that includes a moment arm shift adjuster for adjusting the spring tension on the back frame.

Abstract: An office chair has a seat (1) mounted on a base (2) so that its inclination can be adjusted with a mechanism (4). The mechanism has a spring (28) mounted in compression between the seat and base, and a manual control (20) acts to adjust the extent of compression of the spring and also the direction of application of the spring force so that a generally linear resistance characteristic can be obtained. The spring (28) preferably has a lower support (12) which engages a positionally adjustable fulcrum (15, 18), and an upper support (11) pivotally connected to the lower support (12). The upper support (11) may be rigidly connected via a rigid bar to a chair back (3). A spring and ratchet arrangement (33, 34) may be provided for locking the seat in position relative to the base.

Abstract: A tilt control mechanism for an office chair includes a spring arrangement which permits forward and rearward tilting of the chair while also urging the chair to a normal upright position. The spring arrangement includes front and rear springs which act in combination such that the upward acting forces acting on the chair can be varied during use. The forces being applied by the front spring are adjusted by a side-actuated tension adjustment mechanism which incorporates a wedge block for adjusting the spring forces. Further, the rear springs provide a variable spring force such that the spring force is maximized when in the normal position but is decreased substantially once the chair is fully reclined. This reduction in spring force allows a user to maintain the chair in the fully reclined position with significantly less force than was required to tilt the chair rearwardly while a sufficient spring force continues to be applied by the front spring to urge the chair to the normal position.