Patent ID: 12207737

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

It should be understood that the term “plurality,” as used herein, means two or more. As shown inFIGS.1and14, the term “longitudinal,” as used herein, means of or relating to a length or lengthwise direction2, for example a direction running from a top to bottom of a backrest8, or a front to back of a seat6, and vice versa (bottom to top and back to front), or along the length of a component, for example a leaf spring80. The term “lateral,” as used herein, means situated on, directed toward or running in a side-to-side direction4of the backrest or seat, for example between a pair of uprights22. The term “coupled” means connected to or engaged with whether directly or indirectly, for example with an intervening member, and does not require the engagement to be fixed or permanent, although it may be fixed or permanent. The term “fixed” means not moveable. The terms “first,” “second,” and so on, as used herein, are not meant to be assigned to a particular component or feature so designated, but rather are simply referring to such components and features in the numerical order as addressed, meaning that a component or feature designated as “first” may later be a “second” such component or feature, depending on the order in which it is referred. It should also be understood that designation of “first” and “second” does not necessarily mean that the two components, features or values so designated are different, meaning for example a first direction may be the same as a second direction, with each simply being applicable to different components or features. The terms “upper,” “lower,” “rear,” “front,” “fore,” “aft,” “vertical,” “horizontal,” and variations or derivatives thereof, refer to the orientations of the exemplary body support structure13as shown inFIGS.1and2from the perspective of a such sitting thereon. The phrase “body support structure” refers to a structure that supports a body, including without limitation office furniture, home furniture, outdoor furniture and vehicular seating, including automotive, airline, marine and passenger train seating, and may include without limitation beds, chairs, sofas, stools, and other pieces of furniture or types of seating structures.

Referring toFIGS.1-5,14-21,45-53and60-63, the seat6and backrest8are supported by a control mechanism10(kinematic control system), which includes a base or support12, which may be configured as a tilt control housing. The base or support12is coupled to and supported by a support column14, which is supported in turn by a bottom base16configured with one or more floor engaging components18, such as glides, casters or other types of feet. The bottom base may be configured with multiple legs. Alternatively, the base support may be supported by other types of support platforms and legs, including a sled base, fixed legs (e.g., 2 or more), a pedestal support, rocker support or other suitable support platforms.

The backrest8includes a frame20configured with a pair of laterally spaced apart uprights22. In one embodiment, the frame20has a top cross member24extending laterally between and connected to the uprights22, and a bottom cross member26extending laterally between and connected to the uprights22, with the top and bottom cross members24,26being longitudinally spaced. In the embodiment shown inFIGS.1-5, a pair of struts50extend downwardly, inwardly and rearwardly from an intermediate position on the uprights22to the bottom cross member26, such that the struts50and upper portions68of the uprights22define a bow shape, which has a forwardly facing convex curvature. In the embodiments shown inFIGS.14-27, a bottom portion23of the uprights22may extend downwardly and rearwardly from an upper or intermediate portion25of the uprights22.

In the embodiment ofFIGS.18-21,29,30,41and45-52, the frame20includes a lateral support202, or cross member, that extends laterally between the uprights22, and has opposite ends204coupled to bottom portions23of the uprights22. In one embodiment, the ends are fixedly coupled to the uprights. A lumbar support206also extends laterally between the uprights22and has opposite ends208coupled to the uprights22. Alternatively, the lumbar support206has laterally spaced ends or free edges that are not connected to the uprights, as shown inFIG.41. The lumbar support206is spaced from the lateral support202, for example vertically spaced above the lateral support202, which defines a lower support203. In one embodiment, the opposite ends208of the lumbar support206are moveable relative to the uprights22, for example laterally translatable or slideable relative to the uprights22such that the lumbar support206may deform or bend in response to a load applied by a user's specific lumbar region. For example, the lumbar support206may bend or deform, or is deformable and bendable, between at least a first and second configuration in response to the load (F) applied by the user as shown inFIGS.29and30. In the embodiment ofFIG.41, the entire lumbar support may deflect rearwardly, as well as bend and deform.

In one embodiment, shown inFIGS.29and30, a strut210, or column/beam, may extend between the lumbar support206and lateral support202. In one embodiment, the strut210has a vertical orientation. As shown inFIG.41, a pair of laterally spaced struts210extend between the lateral support202and lumbar support206. As the lumbar support206bends or deforms, the strut(s)210or beam applies a compressive force (F) to the lumbar support206, which applies a twisting load or torque T, as well as a bending load, to the lateral support202. Because the lateral support202is fixedly connected to the uprights22at the ends69thereof, the lateral support202is torqued, or is twistable between at least first and second configurations as the lumbar support206is deformed between the first and second configurations and provide a restorative force to the lumbar support206through the strut210. In this way, the lateral support202acts as a torsion spring acting on the strut(s)210and lumbar support206, with a middle portion of the lateral support202being rotatably displaced from the compressive force and/or twisting from the strut210while the ends of the lateral support202are rotationally fixed. The lateral support202, and/or the strut(s)210, may also experience bending if the load (F) has a vertical vector component. In one embodiment, the strut210may be disposed between the pair of uprights22, and may be centrally located between the pair of uprights22along a centerline of the backrest. In other embodiments, as shown inFIG.41, a plurality of struts may be disposed between the lumbar support206and lateral support202. As shown inFIG.42, the lumbar support206and/or struts may be disposed between one or more layers or substrates defining a body support member30. For example, the body support member30may be configured with a pair of fabric or textile front and rear layers131,33defining a pocket in which the lumbar support206is disposed. Alternatively, in one embodiment, one of the front and rear layers131,33may be omitted.

The portions68,25of the uprights22, struts50and cross members24,26define a central opening28in the embodiment ofFIGS.1-5, while the uprights22, lower support202and cross member24define a central opening in the embodiment ofFIGS.14-27and45-52. The body support member30, such as a shell (e.g., plastic) or suspension material (e.g., woven or knit textile material), may be disposed across the central opening28and may be secured to the frame20, for example to the uprights22(e.g. upper portions68), struts50, lower support202and/or cross members24,26. The body support member30has a bow shape, with a forwardly protruding lumbar section31defined at the junction between the upper portions68of the uprights and struts50or bottom portion23of the uprights22. In the embodiment ofFIGS.18-27, the lumbar support206is disposed immediately below the junction, although it may be disposed at or above the junction. Lower side edges of the body support member30may be free of attachment to, and spaced from, the lower portions of the uprights22below the lumbar support206. A cushion or other user interface may be secured across the front of the body support member30.

Referring toFIGS.60-63, the body support member, configured for example as a cover, which may be a suspension material, and includes a rear portion800, or cape, that extends from a front portion804and wraps around the backrest and over the cross member24, thereby covering the top and a portion of the rear of the backrest. The rear portion may be connected to the rear surface of the uprights22. The rear portion may include a laterally extending stiffener802located along an edge thereof.

Referring toFIGS.1-4,14-20,45-53and60-63, the seat6includes a longitudinally extending platform, otherwise referred to as a seat carrier32or frame, having a front edge36, side supports38and one or more rear support platforms40,214. The seat carrier32is spaced above the base and creates an open space therebetween that extends from one side of the body support assembly to the other. In one embodiment, the opening65may have a polygonal shape, and may be a quadrilateral or pentagonal shape. It should be understood that the overall appearance of the seat, base and backrest, individually and collectively, including for example the size, shape and orientation of the opening, seat, backrest, frame members, and base, and various links or components interconnected therewith, may be varied, or configured in a manner that presents a different appearance without impairing the operation and function of the elements shown, for example without affecting the relative motion, interface and interaction of those components, including the relative movement therebetween. Those of skill in the art will appreciate that the present configuration shown in those drawing figures, as well as other potential embodiments, are chosen based upon a selected aesthetic for presenting a desired ornamental design appearance that is operational but is not dictated by the functionality of the components and embodiments shown.

A cross member215extends between and connects the platforms214. A body support assembly34may be supported on the platform, or seat carrier32. The body support assembly34may include a secondary frame, otherwise referred to as a seat support42, defining a central opening236. A body support member44, such as a shell or suspension material, is disposed across the central opening236and may be secured to the secondary frame/seat support42. In other embodiments, the platform, or seat carrier32, may define a central opening supporting the body support assembly34, or the body support assembly34may include an upholstered foam cushion.

In one embodiment, shown inFIGS.18-20, and22, the seat support42includes a rear portion220and a front portion222. The rear and front portions form an upper platform238defining the central opening236. The rear portion220may be slideably coupled to the seat carrier32. For example, the seat carrier may define a pair of laterally spaced tracks or rails224, having an upper flange226defining a channel228that opens laterally outwardly. The seat support42has a pair of laterally spaced rails or guides, defined by an edge portion230of side webs234on the rear portion220that extend downwardly and inwardly from the platform238, with the edge portions230extending horizontally and laterally inwardly where they may be received in the channels228. A cross member229extends rearwardly along the rear portion220. The seat support42may slide fore and aft in a longitudinal direction2relative to the seat carrier32to a desired seat depth position. A detent or lock may interface between the seat support and carrier to secure the seat in the desired seat depth position.

The front portion222is cantilevered forwardly from the rear portion220in an unsupported and vertically spaced apart relationship relative to the seat carrier32, or platform. When loaded by a user, the front portion222may deflect downwardly. In one embodiment, the seat has an overall length L s between front and rear edges240,242thereof as shown inFIG.15. The front portion222has a length Lfwhile the rear portion220has a length LR, with LS=LF+LR. In one embodiment, the length LFof the unsupported front portion222defines 50% or less of the overall length LSof the seat support42. A body support member44, such as a shell or suspension material, is disposed across the central opening236and may be secured to the seat support42, for example along an edge thereof. The body support member may also include a foam cushion supported by the shell and a cover disposed over the foam.

Referring toFIGS.1-5and53, a pair of armrests46are coupled to and extend upwardly and forwardly from the rear support platform40, such that the armrests46move with the seat, or platforms32,40. The platform40extends rearwardly under, and has a rear portion positioned rearwardly from, the bottom cross member26of the backrest frame. The platforms may each include an upwardly extending post41, which engages or receives a bottom of the armrest46, which is inserted onto the post. In this way, the armrests46move with the seat, but also do not obstruct the space along the side of the seat such that a user may position their legs along the side thereof. The bottom member26of the backrest frame is spaced apart from the support platform40, and defines a space or gap (“G”) therebetween. As such, the backrest8may move relative to the seat6. The armrests46are outwardly, laterally spaced from the backrest uprights22and extend forwardly from the backrest8, intersecting a lateral projection of the uprights22, such that they are exposed above the sides of the seat6. The seat6is nested between and positioned laterally inboard from the respective uprights22on adjacent sides of the chair. A notch52may be formed in opposite sides48of the seat to receive the uprights22and allow for relative movement therebetween. In other embodiments, the armrests46may be coupled to the platform, or seat carrier32in front of the backrest, and in front of a pivot joint66connecting the seat, and platform, or seat carrier32in particular, to the backrest uprights22. The armrests may be variable height armrests500as shown inFIG.27with a parallelogram support structure, or may be fixed, for example configured with a fixed height stem and arm pad.

Referring toFIG.14-17, an alternative embodiment of the body support structure includes a pair of armrests250, which are coupled to and extend upwardly and forwardly from a pair of rear support platforms214extending laterally outwardly from the seat carrier32, such that the armrests250move with the seat carrier or platforms32,214. In this embodiment, the armrests250may include a lower portion252having a first end254coupled to the support platform214and a second end256. The lower portion252extends upwardly and forwardly from the platform214. A horizontal and longitudinally extending arm support258is coupled to the second end256of the lower portion and is cantilevered rearwardly. The arm support has a free end260disposed in front and outboard of the front surface of the backrest8. As shown inFIGS.62and63, the armrest includes an upright portion820coupled to the platform and a horizontal, cantilevered portion822extending forwardly from the upright portion822. The cantilevered portion822may include a padded portion on a top thereof.

In an alternative embodiment shown inFIG.24, an armrest may be configured as a closed loop, with a rear support joining the arm support258and a lower portion252, which may include a lower portion of the uprights22in one alternative embodiment. The lower portion252may or may not be connected to the uprights. In another embodiment shown inFIG.25, the armrest may again be formed as a closed loop, but with a quadrilateral shape. The armrest has front and rear supports264,262joined with an upper armrest support268and a lower support266, with the lower support266and rear support262joined with the support platform. In yet another embodiment shown inFIG.26, the rear support may be omitted, with the upper support268again having a free end270.

Referring toFIGS.1-4and14-17, the seat6, and in particular the platform, or seat carrier32, is pivotally connected to the base12at a first pivot joint60, which is positioned adjacent a front portion of the seat and base. In one embodiment, the base12has a bottom member62that is connected to the support column14and extends longitudinally, or is cantilevered, forwardly from the support column. The base further includes a front upturned support or yoke, which may have a U-shape, comprising a pair of laterally spaced support platforms64. The pivot joints60may be defined by a living hinge, or by a pivot pin.

Referring toFIGS.45-55, a U-shaped yoke600defines the support with a pair of spaced apart arms602defining the support platforms64. A bottom, central portion604of the yoke is secured to the base12, which may be configured as a housing, made for example from a casting. A plate606, or cross member, extends laterally across the space between the arms602and connects to the support platforms64, for example with fasteners. In one embodiment, the plate is rigid, and may be made of metal such as steel.

Referring toFIGS.1-4, the backrest8, and in particular the uprights22, is pivotally connected to the seat6at the second pivot joint66, which is longitudinally spaced and positioned rearwardly of the first pivot joint60. The uprights22have an uppermost portion68defining in part the central opening, an intermediate portion70between the upper portion and the pivot joint66and a lower portion72extending downwardly from the pivot joint66. The pivot joint66may be defined by a living hinge, or by a pivot pin.

In an illustrative embodiment, a laterally extending torsion leaf spring80has an intermediate, or central, portion82connected to the base12and laterally spaced opposite end portions84connected to the uprights22. In illustrative embodiments, the end portions84are connected particularly to the lower portions72of the uprights22. Opposite arm portions86of the torsion leaf spring80extend between the intermediate portion82and the end portions84and define a pair of links coupling the backrest8to the base12. In one embodiment, the connection between the leaf spring80and base12is positioned rearwardly of the support column14. The leaf spring80may be coupled to the base12, or the rear of the platform, with fasteners, adhesives, bonding, welding or other types of connections, or may be integrally formed therewith as a one-piece unitary structure. In other embodiments, a pair of separate leaf springs may be secured between the base and the pair of uprights, one on each side of the base, or a pair of leaf springs may overlap along the central portion. In other embodiments, a single torsion leaf spring may suffice to connect two components, such as a base and backrest and/or seat.

The torsion leaf springs, and in particular the arm portions86, define a pair of links or flexible portions that are both bendable and twistable between an at-rest configuration and a biased configuration. The backrest8is pivotable and translatable relative to the base12from an upright position to a reclined position as the torsion leaf spring80, and in particular the arm portions86, are bent and twisted between the at-rest configuration and the biased configuration. The torsion leaf spring80, and in particular the arm portions86, biases the backrest8toward the upright or at-rest position from the reclined position. The torsion leaf spring80, or arm portions86, each provide two degrees of freedom, which allows the seat6and backrest8to pivot relative to the base about an axis and each other, with the lower portions72of the uprights22in an illustrative example both pivoting about an axis90, and with the axis90translating relative to the base12, i.e., moving fore/aft and/or up/down relative to the base12as shown inFIG.40. In one embodiment, the axis90moves in at least a forward direction during recline. In one embodiment shown inFIGS.40and43A, the end105of the longitudinal portion of a biasing component300, configured as a torsion leaf spring80, e.g., the outboard end105of the biasing component300positioned along the axis104of the biasing component, moves forwardly and downwardly a distance (D1) to a second position105′. In this way, the torsion leaf spring80, or biasing component300, provides an additional degree of freedom by flexing (bending about a principal axis100of the leaf spring80and twisting about a lateral axis104) instead of sliding and rotating. In other words, the bending and twisting mimics a sliding/rotation joint or crank and slide joint. In this way, the control mechanism10, or kinematic control system, includes the leaf spring80or biasing component300, the base12, seat carrier32and lower portion72, which define three links joined by two pivot joints60,66. The control mechanism10, and the overall linkage mimics a three-bar slide mechanism. It should be understood that the torsion leaf spring, with the twisting and bending deformation, may be used in combination with other linkages and systems. In combination, the overall system is provided with sufficient degrees of freedom to allow the seat and back to recline relative to the base and each other. In addition, the torsion leaf spring provides a restoring or biasing force to the back uprights, resisting the recline of the user and causing the backrest and seat to be biased from the reclined position to the upright (e.g., at-rest) position. The ends of the spring may be rotatably connected to the uprights22, or may be fixedly, non-rotatably connected to the uprights22, with the rotation axis thereby defined along a neutral axis of the leaf spring as the spring twists in torsion. In one embodiment, the torsion leaf spring is the only component directly connecting the uprights22and base12, and the backrest is only connected to the seat at the pivot axis66,129, and to the base via the torsion leaf spring80, and is not otherwise supported by any other links or components.

In one embodiment, the torsion leaf spring80has a rectangular cross section as shown inFIGS.5-6B, and is configured as a thin blade having principal bending axes100,102. The cross section may be constant along the length of the leaf spring, or may vary. The leaf spring80may be configured with first and second principle axes100,102and a longitudinal or neutral axis104, wherein the torsion leaf spring is bendable about at least the first principle axis100(i.e., translation), and wherein the torsion leaf spring is twistable about at least the neutral axis104(rotation). In this way, the spring provides for multi-directional deformation as it is elastically deformed. The torsion leaf spring may have other cross sections that are not rectangular, for example circular, or may have varying cross sections, both in shape and size.

In one embodiment, shown inFIGS.6Aand B, each of the end portions84includes a plurality of fingers106, otherwise referred to as bands, connected to the backrest uprights22. The fingers/bands may be individually connected to the uprights with a non-rotatable or a rotatable connection. In one embodiment, the fingers/bands106are spaced apart along the second principle axis100, and are defined by spaced apart and longitudinally extending slits108made in the leaf spring. In one embodiment, the slits108are linear and parallel to each other. In one embodiment, the slits108are through-openings or extend through the entire thickness of the torsion leaf spring80, and may have the same width, while in other embodiments, the slits108may have varying widths, both individually and relative to each other (i.e., the space between the slits may vary). In an alternative embodiment, the slits108may terminate short of the end of the leaf spring80, with the end of the leaf spring80being connected to the backrest upright22. In an alternative embodiment, the fingers106may be located adjacent to, and be connected to, the base12, or the spring80may have two sets of fingers, with one set located adjacent the base and the other set located adjacent the uprights. The fingers/bands106and/or slits108may have different or the same lengths than other fingers and/or slits. For example, the fingers/bands106and and/or slits108may be longer along a bottom of the spring80, and shorter along the top of the spring80, with or without a gradual lengthening from bottom to top. Likewise, the fingers/bands and/or slits may have different or the same widths, measured along the second principle axis100. In one embodiment, each of the plurality of fingers/bands have lengths less than 50% of an overall length (L) of the leaf spring80. Each of the plurality of fingers/bands may have a length less than 25% of an overall length (L) of the leaf spring, defined between the end portions84of the spring80. In another embodiment, the entirety of the leaf spring80is defined by a plurality of fingers/bands, or individual leaf springs80positioned adjacent one another with a space or gap between each pair of adjacent fingers. The overall length L1may also be considered as the length of a single arm (e.g., approximately ½ L), measured between the central location and an end of the spring, in an alternative embodiment. In one embodiment, at least a portion of the cross-section of the leaf spring, for example the intermediate portion82is solid material, or has a solid cross section without voids (except for fastener openings if applicable). The leaf spring may be made of various resilient materials, including a composite material such as a glass filed thermoplastic. The length and number of fingers/bands may affect the biasing force of the leaf spring80, making the spring softer or harder (less or more stiff), with longer fingers/bands, or more fingers/bands, for example making the spring less stiff. The leaf spring may have various thin regions extending across a width thereof to define flex joints, with the spring having isolated compliance wherein the leaf spring is elastically deformed (e.g., through bending) primarily at the flex joints.

In another embodiment, shown inFIGS.14-23, the biasing component300, configured as a torsion leaf spring, again includes a plurality of spaced apart fingers/bands302defined by spaced apart slits330formed in the biasing component. In one embodiment, the biasing component, or torsion leaf spring, is the only component directly connecting the backrest and base, and the backrest is only connected to the seat at the pivot axis or joint66,129, and to the base via the biasing component300, and is not otherwise supported by any other links or components. At least some of the fingers/bands302have a laterally extending first portion304extending in a first direction, for example a lateral direction4, a second portion306extending in a second direction, for example a longitudinal direction2, and a curved transition portion308, or region, between the first and second portions. It should be understood that first and second portions304and306may also be curved, or have curvature, but with the term “direction” referring to the orientation of a tangential vector. For example, a first direction refers to a vector/tangent312tangential to the first portion304at a first end thereof and a second direction refer to a vector/tangent314tangential to the second portion306at the second end thereof as shown inFIG.23. The first and second directions, or vectors312,314, are non-planar. In various embodiments, the first and second directions, or vectors/tangents312,314, define an angle (a) of 90 degrees or less therebetween. In one embodiment, the first and second vectors/tangents are substantially orthogonal, although in other embodiments the angle may be greater than 90 degrees. The fingers/bands302may have an L-shape, with a first leg defined by the first portion304and defining the end105of the longitudinal portion304, a second leg defined by the second portion306and the transition portion308defined therebetween. The fingers/bands302are spaced apart and defined by slits.

Put another way, slits330may be formed in a leaf spring having a laterally extending component and a longitudinally extending component joined by a transition region, which may be curved. It should be understood that the longitudinally extending component may have a combined fore/aft and up/down orientation. The slits330extend continuously in the laterally and longitudinal extending components and transition region. In one embodiment, the slits330are formed as through-openings extending through the entirety of the thickness of the leaf spring. In one embodiment, the slits330may be filled with a secondary material, such as overmolding. The slits330, including the portions thereof defined in the laterally and longitudinally extending component and transition region may be planar, and lie parallel to each other, meaning the entirety of (e.g., entire length of) one slit is equally spaced from an adjacent slit, or the length thereof. In other embodiments, the slits may be non-planar, or curvilinear, although they be equally spaced from adjacent slits, or not. The biasing component may further include a base portion332. The first portions of the fingers/bands302may extend from and be coupled to the base portion. In one embodiment, the base portion332and fingers/bands302may be integrally formed. It should be understood that in one embodiment, the slits330may extend across the entirety of the base portion332such that the slits on both sides are integrally formed as a continuous slits.

In one embodiment, the biasing component300is integrated into the backrest frame20, with the second portions306extending from and coupled to longitudinally extending and laterally spaced back support members334extending forwardly from and connected to the uprights22. The support members334are relatively rigid and do not elastically deform during recline of the backrest. The entire backrest frame20, including the uprights22, support members334, and biasing component300may be integrally formed as a one-piece member. In one embodiment, the body support structure13includes a pair of laterally spaced biasing components300, which are joined by and include a central base portion332. The base portion332is coupled to the rear of the base12, for example with fasteners, adhesive, or integral molding. In one embodiment, the base portion332may have a first outermost surface profile, and the first portion304includes a second outermost surface profile. The first and second profiles may be the same at a junction of the first portion304and the base portion332.

Alternatively explained, the biasing component/torsion leaf spring300defines a laterally extending deformable link340connected between first and second components that are moveable relative to each other along a path, for example the base12and backrest8are moveable relative to each other. The deformable link340, which may have distributive or isolated compliance, may join other components moveable relative to each other, including for example the seat and base, or the seat and backrest, or any two structures (not limited to body support structures) that are moveable relative to each other, with the deformable link defining the path of movement between the components through the deformation thereof, which path may include multiple degrees of freedom including translation along any of axes100,102,104, and/or rotation about axis104. In other words, the deformable link340may twist about an axis104while bending about a principal axis100, and may also bend about a principal axis102, with the deformable link thereby mimicking a slider/crank joint. The deformable link340may be configured with the plurality of spaced apart elongated slits330, or one or more flex regions as explained in more detail below, or combinations thereof. The deformable link is non-planar, and includes a first portion346, defining an end105, connected to the first component, for example the base12or uprights22, and a second portion344connected to the second component, for example the other of the base12or uprights22. The first and second portions may be joined by an elbow portion342in one embodiment. In one embodiment, the slits330may extend continuously along at least portions of the first, second and elbow portions. The first and second portions define an angle therebetween (e.g., 90 degrees or less), and may be substantially orthogonal in one embodiment, for example with the first portion346extending laterally and the second portion344extending longitudinally (e.g., rearwardly and/or upwardly/downwardly. The first, second and elbow portions346,344,342are integrally formed as a one-piece component. The movement path may include bending and twisting of one or more (or all) of the first, second end elbow portions.

In one embodiment, and referring toFIGS.33-40,43A,43B and44, a biasing component1300, or torsion leaf spring, is configured as a deformable link1340having one or more flex regions1302,1304that provide isolated compliance at those flex regions. The biasing component1300, or deformable link1340, is non-planar, and includes a first portion1346connected to the first component, for example and without limitation the base12, and a second portion1344connected to the second component, for example and without limitation the uprights22. One or both of the first and second portions1346,1344may be relatively rigid and not undergo any substantial elastic deformation during recline. The first and second portions1346,1344may be joined by an elbow portion1342in one embodiment. In other embodiments, the elbow portion may be omitted, with the flex region1304defining the junction between the first and second portions1346,1344. In one embodiment, the first and second portions1346,1344define an angle therebetween (e.g., 90 degrees or less), and may be substantially orthogonal in one embodiment, for example with the first portion1346extending laterally (outwardly and/or upwardly/downward) and the second portion1344extending longitudinally (e.g., rearwardly and/or upwardly/downwardly). In one embodiment, the first, second and elbow portions1346,1344,1342may be integrally formed as a one-piece component.

In one embodiment, the biasing component1300, or deformable link1340, may include a base portion1332, which is coupled to the base12. The base portion1332and first portions1346may lie in, or define, one or more substantially vertical planes (the same or different), or may be oriented in non-vertical planes, for example tilted clockwise or counterclockwise from a vertical plane when viewing the biasing component from the right hand side. The flex region1302separates and joins the base portion1332and the first portion1346. It should be understood that the description of the biasing component is with reference to one side of the body support structure, but with the understanding that the biasing component1300is symmetrical relative to the centerline of the body support structure, meaning for example there are two flex regions1302on each side of the centerline. In one embodiment, the flex region1302may be substantially linear and extends upwardly and outwardly from a bottom of the biasing component to the top thereof at an angle β of between 20 degrees and 60 degrees relative to a principle axis100, e.g., a vertical axis in one embodiment, and may define an angle β of about 35 or 40 degrees in exemplary embodiments. The vertical axis and the axis of the flex region, and the angle β measured therebetween, is defined within the plane of the base portion332,1332. Described another way, β is measured normal to the plane of the base portion332,1332that the blade, or portion1346, reacts against. Conversely, the flex region1302may define an angle in exemplary embodiments of 50-55 degrees relative to a horizontal axis. The base portion332,1332, or plane defined thereby, may be vertical, or may be angled rearwardly at an angle §, as shown for example inFIGS.16and40, wherein § may be between and including 0 to 30 degrees, and is 15 degrees in one embodiment. The angle(s), orientation and location of the flex region1302, or flex regions1302and1304, control the rate of the change of angle of the frame20of the backrest relative to a given recline angle and the base. The flex region1304separates and joins the first and second portions1346,1344. The flex region1304may be substantially linear, or non-linear, and extend along the principle axis100, although it may be oriented at other angles relative to the principle axis100. It should be understood that only a single flex region, e.g. flex region1302, may be incorporated into the biasing component, with the other portions of the deformable link providing distributive compliance through twisting and/or bending to provide the additional degrees of freedom. Alternatively, as shown inFIG.39, more than two flex regions1350,1352may be provided, including a pair of flex regions1350,1352at the junction between the laterally extending and longitudinally extending portions1346,1344, with a transition portion1354extending between the flex regions1350,1352.

The biasing component1300may be configured for example with strategic deformable locations that allow for predetermined deformations, or isolated compliance, and define the flex regions1302,1304,1350,1352, otherwise referred to as “flex joints,” or virtual pivot locations. The phrase “flex region” refers to a portion of the structure that allows for flexing or bending in the designated region, through elastic deformation, thereby allowing or providing for relative flexing movement (e.g., pivoting or bending) of the component, or portions or structure on opposite sides of the flex region, and also thereby defining a virtual pivot location, with the understanding that the virtual pivot axis may move during the flexing, rather than being defined as a hard fixed axis. The various flex regions1302,1304,1350,1352may be formed as living hinges, folds or thin flexible hinges made from the same material as the more rigid adjacent portions1332,1346,1344,1354of the biasing component, but with a thinner cross-section and lower (area) moment of inertia along the principal axis100or axis of the fold at an angle β so as to provide for relative rotation or pivoting between the more rigid pieces by bending or folding of the flex regions1302,1304,1350,1352or living hinges. It should be understood that in alternative embodiments, the flex regions may be configured as fixed hinge points. It should also be understood, however, that the portions1332,1346,1344,1354may also bend (about principal axis100), twist (about axis104) and deform elastically during recline of the body support assembly, and provide for deformation of the overall biasing component through bending and twisting of those portions1336,1344,1354(i.e., distributive compliance) between the flex regions, but with the majority (or entirety in some embodiments) of the elastic deformation intentionally occurring at the flex regions1302,1304,1350,1352.

In one embodiment, as shown inFIGS.33-38,43A,43B and44, the biasing component1300, and the portions1332,1346,1344,1354, may be configured as a blade, having a height and thickness, both of which may vary, but which allow for bending about the principal axis100, or about the flex region1302, but are resistant to bending about the principal axis102. The biasing component1300may also twist about the axis104. In one embodiment, each of the blades may have a greater thickness along a longitudinal centerline thereof, with the blade having an elliptical cross section. In one embodiment, the flex regions1302,1304,1350,1352are formed by making the blade thinner than the surrounding regions, and also making the blade flat or planar across the width of the blade at the flex region. For example, in one embodiment, the adjacent regions of the blade may have a thickness of 2 to 3 times the thickness of the blade in the flex region. In other words, the flex regions1302,1304,1350,1352are introduced by making the blade thin and flat. As such, the flex region has a lesser area moment of inertia, and is less capable of resisting bending, than the adjacent regions. Conversely, the portions1346,1354,1344may be relatively thick between the flex regions1302,1304,1350,1352.

In operation, the backrest8is movable relative to the base12from an upright position to a reclined position as the leaf spring80, or biasing component300,1300is deformed to define the path of movement of the backrest. The leaf spring80or biasing component300,1300biases the backrest8toward the upright (at-rest) position from the reclined position. In one embodiment, the leaf spring80or biasing component300,1300is bendable and twistable between an at-rest configuration (shown inFIG.6B) and a biased configuration (shown inFIG.6A) as the backrest8is pivotable (e.g., about axis104) and is translatable (e.g., along axis102) relative to the base12from the upright position to the reclined position, with the axis90, or end portion105, moving forwardly and/or downwardly depending on the other constraints of the system as shown inFIGS.40and43AThe uprights may also move slightly inboard along the axis100as the leaf spring80or biasing component300,1300deforms. The leaf spring80and biasing components300,1300experience elastic deformation when bending and twisting, as shown inFIGS.23and43A, and applies a return force to the backrest8resisting the recline of the user. In the embodiment ofFIGS.6Aand B, the fingers106each act as an independent torsion leaf spring that experiences torsion and bending.

In one embodiment, and referring toFIGS.14-21, the body support structure includes three basic components, including the base12, the seat6and the backrest8. The seat is pivotally connected to the base12at a first location360, which may be defined by pivot joint60. The backrest8is pivotally connected to the seat at a second location362, which may be defined by pivot joint122, and is fixedly connected to the base12at a third location364, which may be defined in one embodiment as the connection between the base portion332and the base12. The backrest8includes a flexible portion366, which may be defined by the fingers/band and/or slits, or alternatively the portions1346,1344,1354and flex regions1302,1304,1350,1352, disposed between, or connecting, the second and third locations362,364. In some embodiments, the flexible portion366may include the isolated compliance aspects, such as strategic flex regions1302,1304,1350,1352, and distributed compliance components such as the portions1346,1344,1354, which may provide for elastic deformation through bending and twisting. Alternatively, the flexible portion may only include isolated compliance aspects, such as strategic flex regions1302,1304,1350,1352, with the other portions/regions1346,1344,1352remaining rigid and not undergoing distributed compliance or elastic deformation. The backrest8is pivotable and translatable relative to the base12from an upright position to a reclined position as the flexible portion366is bent about the principal axis100and/or twisted about axis104between an at-rest configuration and a biased configuration. In this way, the flexible portion366may provide at least 2 degrees of freedom, allowing for a translation and rotation of the backrest relative to the base and rotation of the seat relative to the base, as shown for example and without limitation by the movement of the end105of the biasing component inFIGS.40and43A, thereby providing a synchro tilt mechanism wherein the seat and backrest recline at different ratios. In other embodiments, the flexible portion366may have more than 2 degrees of freedom defining the movement thereof. In one embodiment, the flexible portion366provides distributive compliance, with the entirety of the flexible portion capable of undergoing elastic deformation, whether through torsion or bending. The isolated compliance, distributive compliance, or combination of isolated and distributive compliance, allows for the motion of the seat and back but eliminates the need for a slide and pivot joint between the backrest and base, or between the seat and backrest.

As mentioned, the flexible portion may also be provided with specific flex regions1302,1304that provide isolated compliance at those joints, while still defining the required motion path of the backrest relative to the seat and base. For example, as shown inFIGS.43A,43B and44, the end105,105′ of the portion1346may rotate and translate forwardly relative to the base12through bending at the flex joint1302, which extends angularly at angle β, as the portion1346,1346′ rotates about the flex joint1302. At the same time, the portion1344,1344′ rotates and translates forwardly relative to the base through bending at the flex joint1304, with the understanding that the flex joint moves (translates and rotates) with the end105. In this embodiment, the portions1346,1344of the blade may not experience any bending or twisting, but rather the motion path is defined only by bending or rotation at the flex joints1302,1304, with the flex joint1302positioned at angle β such that the portion1346moves forwardly and downwardly as the portion1346pivots about the flex joint1302. In other embodiments, the portion1346may also experience some bending or twisting. As shown inFIGS.43Aand B, the end105of portion1346, the portion1344, which may be defined by the support334, and the backrest8rotate about 20 degrees between an upright position and a reclined position. In other embodiments, the end105of portion1346, portion1344, support334and backrest8may rotate between 10 degrees and 30 degrees. As shown inFIGS.43Aand B and44, the end105,105′, portion1344,1344′, support334,334′ and backrest8are rotated about a virtual pivot axis1345, which may be positioned above a body supporting surface1347of the seat6supporting the body of the user and in front of a body supporting surface1349of the backrest8. The rotation of the backrest may also be varied by modifying the initial orientation of the portions1332,1346in an at-rest position, for example by orienting the portions along a vertical plane, or by orienting the portions1332,1346along a plane that is angled clockwise or counterclockwise to the vertical plane, for example at an angle §. Also, as shown for example inFIG.37, the portion1346may be angled rearwardly relative to the base portion1332, and may also be rotated about the axis104, in the at-rest position.

Referring toFIGS.14-22,36,37and44-59, the body support structure includes the base12and a body support component, e.g., seat6or backrest8, movably mounted on the base. The body support component, whether the seat or backrest, is moveable relative to the base between an upright position to a reclined position. In one embodiment, the body support component includes the seat carrier32. At least one strut370has a first end372coupled to one of the base12or the body support component (e.g., seat6or backrest8), and a second end374moveably coupled to the other of the base and the body support component, wherein the second end374,374′ is moveable relative to the other of the base and the body support component between an at-rest position and a stop position as the first end372,372′ is moveable with the body support component. In this embodiment, the end374,374′ is translatable, for example through sliding, and pivotable relative to the other of the base and body support component. It should be understood that in one embodiment, the strut may have a first end connected to the backrest, e.g., an upright, and a second end moveably coupled to the intermediate or base portion of the flexible portion that is connected to the base12, or has a fixed position. The first end372may be connected to the base12or body support component for example by welding, adhesives/bonding, fasteners, co-molding, and/or combinations thereof. In one embodiment, shown for example inFIGS.36,37and44-59, the first end372of the strut370is connected to the support member334of the backrest8and defines a truss structure in combination with the torsion leaf spring80, biasing component300,1300, or deformable link340. In one embodiment, shown inFIG.53, the end of the strut370overlaps with and/or is pocketed in the support member334, for example in an cavity formed along an inner side of the support member. The end of the strut may include a lug609aligned with an opening in the support member. A fastener611is inserted through the opening and lug and secures the strut to the support member334. In other embodiments, the strut may be integrally formed with the base or body support component, or may be coupled with fasteners, bonding or other suitable devices and combinations thereof. The truss is V-shaped or triangular shaped, and interfaces between the backrest8and the base12. The strut370extends forwardly and inwardly from the support member334. The strut370, or a pair of struts, limit(s) the movement of the body support component, whether the backrest8or seat6, relative to the base12when the strut370is in the stop position. In one embodiment, a pair of struts370connect the body support component (e.g., seat6or backrest8) and base12, although it should be understood that a single strut, or more than two struts may be incorporated. In one embodiment, the second end374is translatably coupled to the other of the base12and the body support component (e.g., the seat6or backrest8), such that the second end374is slidable relative to the other of the base12and the body support component between the at-rest position and the stop position, as shown inFIGS.22and44. The second end374may also have some rotational connection to the base12. In one embodiment, the first end372is connected to the seat carrier32, for example fixedly or rotationally connected, while the second end374is moveably (e.g., translatably and/or rotatably) coupled to the base12. If the first end372is fixedly connected, the strut370may experience some bending, while if rotationally connected, the strut370will experience primarily (or only) compression. It should be understood that the connections may be reversed, with the first end372connected to the base12and the second end374connected to the seat carrier32and/or backrest.

In one embodiment, shown inFIG.22, the base12includes a pair of slots376that receive the second ends of the struts370. The inboard end378of the slot376is tapered upwardly and outwardly to partially close the top of the slot376and define a cavity377with a stop379to prevent the end374of the strut370from being forced out of the slot376. As the end374engages the stop379, or end of the cavity, the strut370limits the recline of the seat and back, thereby acting as a tilt limiter. The end374may slide laterally in the slot376. Referring toFIGS.28,31,32and56-59, a biasing component380,382,384may engage and bias the second ends374of the struts370laterally outwardly toward the at-rest position. In various embodiments, the biasing component380may be configured as one of a compression spring382, a leaf spring, a torsion spring, a tension spring384, or any other type of spring. For example, a leaf spring may be configured in a bow shape, with ends395thereof engaging the spaced apart second ends of the struts370.

Referring to the embodiments ofFIGS.53,56,57and59, each strut370includes a lever608coupled to the end of the strut370at a first location614. In one embodiment, the strut370and lever608are integrally formed and connected at an elbow joint610, with the strut and lever defining an acute angle (T) therebetween. An opposite end612of the lever608is pivotably coupled to the other of the base and the body support component, shown as the base, at a second location616spaced from the first location, defining for example a vertical axis618. A portion of a return biasing force may be applied to the strut by way of elastic bending at the elbow joint610. In another embodiments, the lever and608and strut370may be rotationally coupled at that joint. In another embodiment, the end612of the lever608may be non-rotatably fixed to the base or body support component, wherein the lever608may provide an additional return biasing force to the strut through bending of the lever. The base12may include a pair of posts620pivotally engaged by sockets622formed at the ends of the lever and disposed over the posts, as shown inFIG.56. Conversely, the lever608may include a post630pivotally coupled to the other of the base or body support component and defining the pivot axis618. In an alternative embodiment, shown inFIG.58, first and second levers are coupled with a laterally extending cross member624, which forms a bow and provides a biasing force to the levers by way of bending. An auxiliary biasing component626, shown as compression springs, may also bias the levers608, e.g., laterally outwardly. The biasing component(s)626engages the lever(s)608between the first and second locations614,616, thereby acting as a fulcrum. In one embodiment, the biasing component may be replaced by a non-resilient member, acting as a fulcrum moving along and changing the effective length of the lever. In one embodiment, the biasing component626is configured as a compression spring that is moveable relative to the lever between the first and second locations, for example in the longitudinal direction2. In one embodiment, the spring is configured as a compression spring that is translatable (e.g., slidable) relative to the lever608in the longitudinal direction2. As the spring moves closer to the end374of the strut, or first location614, a larger biasing force is applied to the strut370to bias the seat and backrest to the at-rest position. It should be understood that the biasing component may include at least one of a compression spring, a leaf spring and/or a tension spring, or combinations thereof.

Referring toFIG.33, a rocker1206may be rotatably connected to the base12about an axis1204, for example with a pin1207. The second end374of each strut may engage a first arm or first location1208of the rocker spaced apart from the axis1204. A biasing member380, shown as a compression spring, engages a second arm, or second location1210, spaced apart from the axis1204and first location1208. In operation, the strut370applies a load through the second end374to the first location, thereby rotating the rocker about the axis1204. The biasing component300applies a counterforce to the rocker at the second location1210resisting the rotation of the rocker1206. An adjustment member1220may engage and support an opposite end1230of the biasing member380. The adjustment member1220may be configured as a wedge, or may be moved laterally to move the end1230of the biasing member380and thereby shift the moment arm of the biasing member380as applied to the rocker1206. In other words, the orientation of the biasing member380may be changed such that the load applied to the end374by the rocker1206is increased or decreased.

When the user sits in the chair, the struts370and biasing member380, or component, provide an auxiliary, or secondary, biasing force that correlates to the weight of the user, thereby providing a weight sensitive control. In particular, as the user sits in the chair, the biasing component300,1300may deflect or deform, through bending and torsion, with the struts370thereby moving in the slot376against the force of the biasing component380,382,384, which provides for a secondary biasing or support of the user. The biasing component300,1300may provide 30-70% of the return energy of the overall system, while the biasing component380may provide 70-30% of the return energy of the system.

The amount of force applied by the biasing component380may be adjusted, for example with an adjuster390that is adjustable to vary the biasing force, shown for example inFIGS.28,31,32,33,56-59. In one embodiment, the adjuster390may include a wedge391moveable relative to the biasing member380,382. For example as shown inFIG.28, the wedge391may be moved laterally to deflect or limit the deflection of the biasing component380, configured as a leaf spring. Or, as shown inFIG.31, the wedge391may be moved vertically to increase the compression force applied by a pair of compression springs382. As shown inFIG.32, the adjuster390may include a pair of laterally moveably supports393that adjust the pretension of a tension spring384. The supports may also be incorporated into the embodiment ofFIG.31to adjust the pretension of the compression springs. As noted above, the struts370may also be introduced between the backrest and the base, with one end fixed to one of the backrest and base and the other end movable relative thereto. As shown inFIG.22, the second ends of the struts370are laterally moveable relative to the base, and are translatable in the slots. Moreover, as the seat reclines, the struts370may also rotate slightly relative to the base, with the slots configured to allow for the additional degrees of freedom. As shown inFIGS.56-59, the struts370, and the ends374in particular, extend through slots642formed in side walls of the base. The second ends374of the first and second struts are moveable, e.g., laterally, toward and away from each other.

Referring toFIGS.56-59, the adjuster390may include a centrally located block or housing660, which is moveable fore-aft in a longitudinal direction2. A pair of biasing components626, configured as springs, are engaged/coupled to opposite sides664,666of the housing. The housing660may be moveably coupled to base along a longitudinally extending track668, formed for example along a top or bottom of the base. An actuator (not shown) may be engaged to rotate a spur gear670about a horizontal axis meshing or engaged with the track, which may include a linear rack672, so as to move the housing and biasing components in the longitudinal direction2.

Referring to57, a pair of variable back stops680are provided to engage the ends374of the struts370and limit the movement thereof and the associated recline of the backrest8and seat6. The back stops680are moveable relative to the struts370. In one embodiment, the back stops680are rotatable about a post684defining a vertical axis682. Each variable back stop includes a plurality of stop surfaces686,688,690, shown as teeth. In one embodiment, the back stops680are pivotally coupled to the base about a pair of pivot axes682. The back stops680may be pivoted to present/align the different stop surfaces686,688,690with the ends374of the struts. For example, as shown inFIG.57, the back stops680are positioned to prevent any recline, or maintain the backrest and seat in a full upright position, with the stop surface686engaging the end374of the strut. As the back stops680are rotated, two additional stop surfaces688,690may be aligned with the struts370to provide an intermediate stop and a full-recline stop.

An actuator692includes a pair of arms694pivotally connected to the back stops680at a location696spaced from the pivot axis682. A pull member698is pivotally or hingedly connect to the arms694about flex joints708. The pull member698may be actuated fore and aft along the longitudinal direction2to move the arms694and thereby rotate or pivot the back stop680to the desired position. In other embodiments, the back stops may be translated, or slid to various stop positions, rather than being rotated, or the back stops may undergo both translation and rotation. A cable, or other movement input, may be coupled to the pull member to effect movement of the actuator692.

Referring toFIGS.7-13, another embodiment of a body support structure13, configured as a chair, includes a base112defining a platform114or bottom member. The base112is connected to a support column14and extends, or is cantilevered, forwardly from the support column14. In this embodiment, the backrest includes a pair of laterally spaced support members116that extend forwardly from the uprights22and define a rear link or bar118connecting the base112and seat6. The support members, or rear link118, are connected to the base112at a first pivot joint120and to a portion of the seat, such as the seat carrier32, at a second pivot joint122positioned upwardly and rearwardly from the first pivot joint120. Likewise, referring toFIGS.14-21, support members334include upstanding arms337that are joined to the seat carrier32at pivot joint122positioned rearwardly of pivot joint60.

Referring toFIGS.7-13, a front link124or bar is are connected to the base112at a third pivot joint126and to the seat6at a fourth pivot joint129positioned upwardly and forwardly from the third pivot joint126. The seat platform/carrier32and base112define two other links (bars) of a four-bar mechanism, with the base112remaining stationary. It should be understood that the rear link118may alternatively be a single rear link, and that the front link124may be a single link, or two or more laterally spaced links. A leaf spring119extends between the base adjacent a connection to the rear link118and the seat carrier or platform32, adjacent a connection to the front link124, and provides a biasing return force for the chair.

Referring toFIGS.11-13, the front link124has a centerline128defined along a length thereof, which centerline128may be linear or curved, and which is defined as the neutral axis of the front link124. The front link124extends between and movably supports a body support component, e.g., the seat carrier or platform32, on the base112. The front link124is pivotally connected to the base112at the pivot joint126positioned on a first side of the centerline128. The front link124is pivotally connected to the body support component at the pivot joint129on a second side of the centerline128opposite the first side. A virtual link130, defined between the pivot joints126,129or virtual pivot axis defined by the pivot joints, crosses or intersects the centerline128between the opposite ends of the centerline. In one embodiment, at least an intermediate portion of the front link124is linear and defines the centerline128. The centerline128may have a first orientation defining a first acute angle relative to a vertical axis, wherein the first orientation has a positive slope, while the virtual link130has a second orientation defining a second acute angle relative to the vertical axis, wherein the second orientation has a negative slope, with the understanding that the slopes are viewed from the left hand side of the body support structure as shown inFIGS.11-13. It should be understood that the first slope of the centerline128, if not linear, is measured at the midpoint of the centerline128, for example a tangent of the centerline at the midpoint if the centerline is curved.

As shown, the body support structure13, or component, is configured as a seat6. It should be understood, however, that the body support component may alternatively be configured as, or include, a backrest or other component. At the same time, it should be understood that the link124may be positioned at any location, including a rear link location, and may interconnect any two components. In the configuration where the link124supports a front of the seat, movement of the front of the seat is weight activated, meaning the weight of the user is taken into account when reclining since the increase in potential energy is offset by the kinetic energy required to recline. In this way, the system may provide more resistance to a heavier user to help counterbalance the user. Due to this orientation, and the configuration of the front link124and pivot joints126,129, the front of the seat does not move, forwardly, downwardly or rearwardly, when loaded vertically as the user sits on the chair. Rather, the front link124acts as a stop between the seat and the base, such that the entire seat does not move downwardly in response to a vertical load. Rather, the seat and backrest only move when the user reclines, meaning the user has to actively recline.

In operation, due to the crossing or intersection of the virtual link130and centerline128, the link124provides a counterintuitive motion during recline. In particular, the link124, with its rearwardly inclined orientation of the centerline and positive slope (when viewed from the left side), would intuitively lead to the upper end of the link124dropping during recline. In reality, however, the virtual link130defines the arc of rotation, which with the forwardly inclined orientation of the virtual link130and negative slope (when viewed from the left hand side) results in the upper end of the link124raising during recline as the pivot joint129follows a curved trajectory to129′. It should be understood that the visual may be reversed, with an upper portion of the link124having an appearance of being raised during recline, while in reality the upper portion drops during recline due to the orientation of the virtual axis130.

Referring toFIGS.11-20, the pivot joints122,126,129,362may be configured as a living hinge139,140,142, formed for example from a bent panel secured between the components for example with fasteners, adhesives or other suitable connections. It should be understood that the pivots may be configured as other pivot joints, including a hinge pin. The link124and the portions144,146of the base and/or body support component (e.g., seat) attached to the link124, for example the portions144,146underlying/overlying and coupled to the living hinges140,142at the first and second pivots, have a Z-shape as shown inFIGS.11-13. The pivot joints126,129may also be configured with a flexible blade, creating a “peelable” joint as further disclosed below.

Referring toFIGS.7-10and14-20, the pair of rear links118, or backrest support members334, are shown as being coupled to the base112,12. In the embodiment ofFIGS.7-10, the link(s)118have a bottom surface150that overlies a portion/surface152of the base, or support. A flexible blade154, or panel, includes a first surface156abutting and connected to the base, or support, at a first location158, for example with a fastener164, adhesive, or other suitable attachment system. Alternatively, as shown inFIGS.53and55, the flexible blade154connects the yoke600, and plate606in particular, with the seat carrier32, with the first surface156abutting and connected to the yoke600or plate606at the first location with the fastener164. The blade154includes a second surface160opposite the first surface abutting and connected to the bottom of the link118, or bottom of the seat carrier, at a second location162, for example with a fastener166, adhesive, or other suitable attachment system. The first and second locations158,162are longitudinally spaced apart along the blade. In one embodiment, the blade154is planar. The flexible blade154functions as a hinge and is bendable/peelable, or elastically deformable, between an at-rest configuration and a biased configuration. The link118is pivoted relative to the base112from a first position to a second position as the blade154is bent, or peeled upwardly, between the at-rest configuration and the biased configuration. At the same time, due to the elastic deformation of the blade154, the blade154biases the link118toward the first position from the second position. In various embodiments, the blade154may be made of metal, such as steel, or various plastic and composite materials, including thermoplastic materials. The same type of peelable joint may be incorporated between the back support member334and the seat carrier32at pivot location362, and also at pivot joint location360between the base12and the seat carrier32.

A stop170, or limit, may be engageable with the link118to limit pivoting of the link118relative to the base112at the second position. The stop170may be connected to the support or the link and engage the other of the link or the support. In one embodiment, the stop170may engage the link adjacent the first location158. For example, the stop170may be disposed between the link and one of the blade and/or support. The stop170may be configured as a block with an engagement surface172that is angled to mate with and abut an engagement surface174of the link118as the link pivots to the second position. In this embodiment, the stop170acts in compression as the link118is pivoted to the second position. Alternatively, the stop170may be fixed to the link118and engage the link118or the surface160of the blade154, while still acting in compression.

In one embodiment, a stop180engages the link118adjacent the second location162. In this embodiment, the stop170acts in tension as the link118is pivoted to the second position. The stop180may be configured as a post, such as a screw having a shaft182secured in the link118and a head184at one end of the shaft. The shaft182is coupled to the bottom surface of the link118and extends through an opening in186the support. The head defines an engagement portion, which engages a stop surface190on the support. The support112may include a cavity188in which the stop member moves during recline until the engagement portion engages the stop surface190, configured as an upper wall of the cavity. It should be understood that the stop180may be secured to the link112and have a stop surface that engages the link118. Although the link ofFIGS.7-9is shown as being connected between the base and backrest inFIG.11, it should be understood that the link may alternatively be connected between the base and seat, or between other components.

It should be understood that two or more of the various links112,124,118,32and living hinges139,140,142, and/or blade154may be integrally formed as a unitary component, for example from additive manufacturing such as 3-D printing. Similarly, two or more of the leaf spring 80/300, backrest uprights22and/or base12may be integrally formed as a unitary component, for example from additive manufacturing such as 3-D printing.

For example, as shown inFIGS.53-54B, an energy loop700is integrally formed to define the flexible blade154, the biasing component1300and a living hinge702connecting the upstanding arms337of the rear link118with the seat carrier32. The energy loop includes a pair of laterally spaced enclosures712, defining tubes, that fitted over/around the arms337. The energy loop includes a pair of bands714, or connectors, that extend forwardly from the enclosures712and define in part the flexible blade154. The energy loop further includes a laterally extending cross member716connecting the bands714, which are secured to the bottom of the seat carrier32. The cross member716also defines in part the laterally extending flexible blade154, which forms the peel joint. The cross member716is also secured to the plate606along the length thereof with a plurality of fasteners166at a location spaced apart from the fasteners164securing the cross member to the seat carrier, thereby allowing the flexible blade154to bend and define the peel joint as the seat6is rotated relative to the yoke600. The energy loop is coupled to the bottom of the seat carrier, for example along the cross member716and along the bands714.

The energy loop is also coupled to the backrest by way of the enclosures712fitted over the arms337, and connects the backrest to the seat and defines the pivot joint therebetween. A pair of stops724, configured as plates, are secured to the top of each of the upstanding arms337. The stops724are disposed in an opening or cavity726formed in the bottom of the seat carrier, and engage a rear surface728of the cavity when the seat and backrest are moved to the reclined position as shown inFIG.54B. The yoke600may be made of metal, such as aluminum, while the plate606and stops724may be made of metal, such as steel. As the seat and backrest are reclined, a portion of the bands714adjacent the enclosures712of the energy loop flex to provide for pivoting between the seat and backrest. The seat carrier, energy loop and struts may be made of a glass reinforced polymer, or thermoplastic (e.g., nylon plastic), and may include glass reinforced tape in-molded with the energy loop at various locations.

Although the present invention has been described with reference to preferred embodiments, those skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. As such, it is intended that the foregoing detailed description be regarded as illustrative rather than limiting and that it is the appended claims, including all equivalents thereof, which are intended to define the scope of the invention.