Abstract: A chair includes a base having a vertically extendable gas spring with an upwardly disposed release button movable horizontally/laterally between a vertically oriented locked position where the gas spring is lock and non-extendable, and a laterally shifted actuated position where the gas spring is released and extendable. A seat is mounted on the gas spring and includes an actuator constructed to selectively move the release button between the locked position and the actuated position with a sideways movement. The actuator includes a link slidably mounted to a control housing under the seat for horizontal movement, and a lever that is pivoted to a side of the control housing for operating the link. The link includes an aperture with angled side surfaces configured to facilitate downward assembly of the link onto the release button, but so that the side surfaces will actuate the release button when the link is moved laterally by the lever.

Abstract: A chair includes a back frame and a flexible back support operably supported on the back frame. The flexible back support includes a flexible lumbar region and a flanged bracket pivotally connected to the back frame at a back support pivot. A force adjusting device is attached to the back frame at the back support pivot for adjusting a torsional spring-generated biasing force on the flanged bracket relative to the back frame. The force adjusting device includes a housing, a base attached to the housing, a spring operably mounted in the housing, and a gear arrangement operably connected to a cup-shaped handle to biasingly adjust a position of the spring with mechanical advantage to adjust a tension of the spring. A clutch is operably attached between the gear arrangement and the handle.

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

Abstract: A chair is provided having a base assembly including a base frame, a back frame pivoted to the base frame for movement between upright and reclined positions, and a seat slidably supported on the base frame and pivoted to the back frame so that the seat moves forwardly and its rear moves forwardly and downwardly with the back frame upon recline. 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 transverse spring, a lever, and 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A chair is provided having a base assembly, a back assembly pivoted to the base assembly for movement between upright and reclined positions, and a seat slidably supported on the base assembly and pivoted to the back frame so that the seat moves forwardly and its rear moves forwardly and downwardly with the back frame upon recline. 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.

Abstract: A chair base includes a leg assembly having a plurality of radially extending legs, and a leg cover adapted to cover the legs. The tubular legs have a top surface divided by a centerline and have apertures offset from the centerline. The leg covers are adapted to cover the legs, and the leg covers include downwardly extending off-centered bosses for engaging the apertures. Each of the tubular legs has an end with aligned vertical holes therein. A sleeve-like pintle receiver is located in the aligned vertical holes and flared at its top and bottom to hold the pintle receiver in the tubular legs. The leg assembly includes a tubular center hub. The plurality of radially extending tubular legs each have a top wall, a bottom wall, and opposing sidewalls, the top and bottom walls each having an arcuately shaped end engaging the center hub. A pair of ring welds extends continuously circumferentially around the center hub for welding the arcuately shaped ends of the top and bottom walls to the center hub.

Abstract: A chair base includes a leg assembly having a plurality of radially-extending legs, and a leg cover adapted to cover the legs. The tubular legs have a top surface divided by a center line and have apertures offset from the center line. The leg covers are adapted to cover the legs, and the leg covers including downwardly extending off-centered bosses for engaging the apertures. Each of the tubular legs have an end with aligned vertical holes therein. A sleeve-like pintle retainer is located in the aligned vertical holes and flared at its top and bottom to hold the pintle retainer in the tubular legs. The leg assembly includes a tubular center hub. The plurality of radially extending tubular legs each have a top wall, a bottom wall and opposing side walls, the top and bottom walls each having an arcuately shaped end engaging the center hub. A pair of ring welds extend continuously circumferentially around the center hub for welding the arcuately shaped ends of the top and bottom walls to the center hub.

Abstract: 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 include a non-adjustable seat support module, a seat-angle-adjustable seat support module, and a seat-depth-adjustable seat support module.

Abstract: A chair 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 frame and pivoted to the back assembly 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: A chair base connection assembly for connecting a pipestand to a chair base includes an outer sleeve having opposing flared ends, an inner sleeve having a tapered inner diameter for engaging the pipestand and an outer surface having a taper at an upper end for engaging an inner flared surface at the upper end of the outer sleeve and external threads at the lower end for engaging a tapered intermediate nut having an outer flared surface which engages an inner flared surface on the lower end of the outer sleeve. The chair base connection assembly of this invention provides a stable, strong, wobble-free connection between the base and the pipestand, while allowing greater dimensional variability of the components comprising the chair base connection assembly, thereby reducing the manufacturing costs.

Abstract: 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 include a non-adjustable seat support module, a seat-angle-adjustable seat support module, and a seat-depth-adjustable seat support module.

Abstract: 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 include a non-adjustable seat support module, a seat-angle-adjustable seat support module, and a seat-depth-adjustable seat support module.

Abstract: 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 include a non-adjustable seat support module, a seat-angle-adjustable seat support module, and a seat-depth-adjustable seat support module.