Steelcase Inc.

Glenn A Knoblock

Kurt R Heidmann

Larry DeKraker

Arnold B Dammermann

David S Teppo

Gordon J Peterson

Charles P Roossien

Robert M Scheper

Gardner J Klaasen, Ii

Michael J Yancharas

Edward H Punches

Kevin A Ekdahl

James A Perkins

James P Steffens

Brian H Root

Eric T McClure

Robert S Grooters

David D Sayers

Patrick P Schwoerer

Michel A Lamart

Brian L Christensen

Noe Palacios

Greg A VanStee

John Hanna J Hasbany

Michael W Haan

Robert J Battey

Michelle R Johnson

Brian L Scolten

Russell T Holdredge

Carl V Forslund, Iii

Jeffrey A Hall

Dale M Groendal

Frederick S Faiks

Duane M Beukema

Craig M Anderson

Daryl Knoblock, Legal Representative

John Hanna Hasbany

Micahel W Haan

Charles P Roosien

Edward H Punchies

Gardner J Ii Klaasen

Kevin A Edkahi

A back support includes a base, a seat, and a back frame pivoted to the base. The seating unit has a flexible back (i.e., back shell) supported on the back frame and having stiff upper and lower sections connected by a forwardly protruding flexible lumbar section for providing lumbar support to a seated user. A spring mechanism is connected to the back frame and to a center lower edge of the flexible back. The spring mechanism biases the flexible back to bias the lumbar toward a forwardly protruding shape to provide optimal lumbar support when in the upright position and also during recline of the seated user.

Back support for seating unit

A seating unit includes a seat and back operably supported for synchronized reclining movement. The back includes a back support with separate upper and lower portions pivotally coupled to a back frame at upper and lower connections, respectively. The upper and lower portions combine to define a forwardly-protruding convex shape and include mating structure forming an expansion joint that permits collapse and expansion as the upper and lower portions are flexed between a more-convex shape and a more-planar shape. In one form, the lower portion includes first and second sections pivoted together, with the upper portion and the first and second sections forming thoracic, lumbar, and pelvic regions of the back support, respectively.

Seating unit including novel back construction

A back construction for a seating unit includes a back frame, and a compliant back having a forwardly-protruding lumbar support section that is characteristically flexible and bendable, such that the compliant back can be flexed to a plurality of different convex shapes. Top and bottom connections pivotally connect the compliant back to the back frame. An adjustable force-generating mechanism is operably attached to at least one of the compliant back and the back frame. The force-generating mechanism is constructed to provide an adjustable biasing force that adjustably biases the lumbar support section forwardly for optimal lumbar support for a seated user's back, but the force-generating mechanism characteristically provides the biasing force without forcing a shape change in the compliant back. A vertically adjustable lumbar support is slidably attached to the back shell.

A back for a seating unit, such as a chair, includes a back frame and a compliant back that is flexibly bendable to define different curvilinear shapes for sympathetically and ergonomically supporting a seated user's back. The back includes a bracket with forwardly-extending flanges pivotally connecting the compliant back to the back frame at a bottom connection generally aligned with a seated user's hip joint. The back also includes a top connection pivotally connecting the back to the back frame above the first connection. An adjustable torsional force-generating mechanism is connected to the first connection that biases a lumbar portion of the compliant back forward with respect to the chair. The top and bottom connections, in combination with the adjustable force generating mechanism, constrain the compliant back to move over a range that provides excellent ergonomic lumbar support to a seated user.

Back for seating unit

A seating unit includes a flexible back including a concavely-shaped lumbar region, and a tensioned cover stretched over the concavely-shaped lumbar region. A lumbar device is fit between the front surface and the covering, with a tension of the covering biasing the lumbar device against the lumbar region and resulting in a frictional force retaining the lumbar device in a selected vertical position. In one form, the lumbar device is sufficiently stiff to maintain its vertical cross sectional shape and to change a shape of the lumbar region as the lumbar device is adjusted vertically, but is sufficiently flexible to conform to a horizontal shape of the lumbar region as a seated user moves and twists while seated in the seating unit.

Lumbar device

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. The moment arm shift adjuster is readily adjustable and includes an overtorque device to prevent damage to components of the energy mechanism.

Seating unit with novel seat construction

A seating unit is provided having a base assembly with a particularly shaped housing and rigid upright side arms, 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. A novel energy mechanism is provided that includes a moment arm shift adjuster for adjusting the spring tension on the back frame. The moment arm shift adjuster is readily adjustable and includes an overtorque device to prevent damage to components of the energy mechanism.

Seating unit with reclineable back and forwardly movable seat

A back for a seating unit, such as a chair, includes a back frame and a compliant back that is flexibly bendable to define different curvilinear shapes for sympathetically and ergonomically supporting a seated user's back. The back includes a belt bracket with forwardly-extending flanges pivotally connecting the back to the back frame at a first connection generally aligned with a seated user's hip joint. The back includes a second connection pivotally connecting the back to the back frame at a second location spaced vertically above the first connection. An adjustable force generating mechanism is connected to the first connection that biases a lumbar portion of the back forward with respect to the chair. The first and second connections, in combination with the adjustable force generating mechanism, constrain the compliant back to move over a range that provides excellent ergonomic lumbar support to a seated user.

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. A novel energy mechanism is provided that includes a moment arm shift adjuster for adjusting the spring tension on the back frame. The moment arm shift adjuster is readily adjustable and includes an overtorque device to prevent damage to components of the energy mechanism.

An armrest construction for chairs includes an armrest support having a lower end constructed for attachment to a chair, an upper end, and a mounting block attached to the upper end. A pivot block is pivoted to the mounting block at a main pivot, the pivot block having an upwardly-extending follower. First and second gears are each pivoted to the pivot block, the gears having intermeshing teeth at an inner end such that rotation of the first gear causes the second gear to simultaneously rotate in an opposite direction, the first and second gears further having outer ends. A support plate having pivot/slide members engages the outer ends of the first and second gears, and further has a guide operably engaging the follower to guide lateral movement of the support plate along a predetermined path. The support plate is rotatable about the main pivot to adjust the angular orientation of the armrest construction and is laterally movable along continuously parallel positions to adjust a width of the armrest construction relative to the chair. The armrest construction is mounted on a vertically-adjustable armrest support member for optimal adjustability.

Seating unit with adjustable armrest

Adjustable armrest for chairs

A back construction for a chair includes a back shell having a plurality of horizontal bands defining a flexible lumbar section, with the back shell including non-parallel guides defined along its edges. A vertically adjustable lumbar support includes a panel body located at the flexible lumbar section, a bent wire member that engages the panel body and that is stretchable laterally, and opposing handles attached to ends of the bent wire member that engage the non-parallel guides. The opposing handles slidingly follow the guides and are movable between a first position where the bent wire member is flexed to a first width dimension, and a second position where the bent wire member is flexed to a second width dimension different than the first width dimension. Slots in the panel body retain the bent wire member to the panel body, but permit the bent wire member to be stretched horizontally during vertical adjustment of the lumbar support. The panel body includes generously radiused upper and lower edges shaped to slide over top and bottom edges of the plurality of horizontal bands without catching on and unacceptably twisting individual ones of the bands when the vertically adjustable lumbar support is vertically adjusted.

Chair having adjustable lumbar support

A chair construction and method for building a chair having selected features are provided. The construction includes a plurality of interchangeable different components including different base assemblies, back assemblies, seats, arms, and chair controls that can be selected to provide different features on a 'customized' chair. The different chair controls are constructed from a selected one of a plurality of interchangeable energy modules and a selected one of a plurality of interchangeable seat support modules. All components include standardized connections for engaging the related components, and further include various mechanisms and designs so that by selecting particular components, a chair having various features and appearances can be provided. For example, the plurality of interchangeable seat support modules includes a non-adjustable seat support module, a seat-angle-adjustable seat support module, and a seat-depth-adjustable seat support module. Also, the plurality of interchangeable chair control modules include a non-lockable energy module, a back lockable energy module, and a multi-position backstop energy module, each connectable to a selected one of the aforementioned seat support modules. The modularity of these components facilitates assembly including on-site assembly, repair, and post-assembly upgrading of the chair. Further, the seat support is connected by removable pivot pins to allow assembly, retrofit and/or modification in the field. The tension adjustment mechanism, the seat height actuator mechanism, and the pivot connections are constructed for durability, performance, assembleability, compactness of design, and to minimize the number of and complexity of parts. The method includes selecting modules from a menu of interconnectable/interchangeable modules to construct a chair control, and further selecting modules from a menu of interchangeable components to construct a chair having selected features.

Modular chair construction and method of assembly

A chair is provided having a base assembly with a particularly shaped housing and rigid upright side arms, 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. A novel energy mechanism is provided that includes a moment arm shift adjuster for adjusting the spring tension on the back frame. The moment arm shift adjuster is readily adjustable and includes an overtorque device to prevent damage to components of the energy mechanism.

Synchrotilt chair with forwardly movable seat

Growing community of inventors

Kentwood, MI, United States of America

Glenn A Knoblock