Patent Application
20240074587
The present invention relates to an office chair and more particularly, to a backrest portion of an office chair.
The market for office seating continues to demand more than just a place to sit. Today's users want comfort, function, and adjustability, all in an aesthetically pleasing configuration. One common type of office chair includes a seat back support, or backrest, that includes a foam cushion covered with an upholstery. The cushion provides a degree of comfort for the back of a user, and can be upholstered in a wide variety of fabrics and materials depending on the desired function and aesthetics. In some cases, however, it can be difficult to manufacture these upholstered back supports, particularly when adding features to provide enhanced support characteristics for the back support. For example, it can be difficult to incorporate a user adjustable lumbar support into an upholstered back where the user can conveniently adjust the position of the lumbar support. Past attempts have focused on vertical adjustability of the entire upholstered back. It can be difficult to provide lumbar adjustment in a context where the adjustment can be meaningfully experienced by the user, and the seat back and lumbar mechanism are covered by the upholstery in an aesthetically pleasing manner.
The present invention provides an upholstered back support for an office type chair with easy to manufacture and aesthetically pleasing comfort and support features. In one embodiment, the back support includes a support frame, front and rear shells, a cushion and a cover. The rear shell is mounted to the support frame, and includes a rear surface facing the support frame and a front surface opposite the rear surface. The front shell has a rear surface facing the rear shell and a front surface opposite the rear surface. The cushion has a rear surface facing the front shell and a front surface opposite the rear surface. The cover is positioned over the front surface of the cushion to cover the cushion.
In one embodiment, the cover has a perimeter edge that wraps around the side of the cushion and the front shell and is inserted between the front and rear shells to form a finished edge for the cover. In another embodiment a rear cover may extend over the rear surface of the rear shell, and may also include a perimeter that wraps around the rear shell and is inserted between the front and rear shells. The cover may be a variety of materials, including a fabric.
In another embodiment, the back support includes a lumbar pad positioned between the front shell and the rear shell. The lumbar pad may be vertically adjustable within a lumbar region of the back support. In one embodiment, the rear shell defines an opening in the lumbar region, and the back support includes a handle having a portion extending through the rear shell opening and attached to the lumbar pad, wherein movement of the handle causes corresponding movement of the lumbar pad.
In one embodiment, the front shell includes features configured to engage and interact with the lumbar pad. For example, at least one lumbar enhancement rib may extend from the rear surface of the front shell in a direction toward the rear shell, and the lumbar pad may engage the lumbar enhancement rib in at least one position during the vertical adjustment of the lumbar pad. The lumbar enhancement rib may extend in a generally vertical direction and defines a rib height in a direction extending away from the rear surface of the front shell. In one embodiment, the rib height at the upper end of the lumbar enhancement rib is greater than the rib height at the bottom, and in another embodiment the rib height gradually increases approaching the upper end of the lumbar enhancement rib. The interference between the lumbar pad and the lumbar enhancement rib may act to augment and enhance the user experience of lumbar support on the front shell as the lumbar pad is vertically adjusted.
The front shell may also include a central flex region that is capable of flexing, and may also be capable of moving with respect to the remainder of the front shell. In one embodiment the central flex section is separated from the remainder of the front shell by an outer slot extending around the central flex section to enable flexing or movement of the central flex section with respect to the remainder of the front shell. The central flex section is connected to the remainder of the front shell only by a series of connector webs, with each of the webs traversing the outer slot. The central flex section includes a top edge, left and right lateral edges, and a bottom edge formed by the outer slot, and in one embodiment there are no connector webs along the top edge. In another embodiment, the back support includes at least one left connector web on the left lateral edge of the central flex section and at least one right connector web on the right edge of the central flex section, the left and right connector webs spaced from the top edge of the central flex section. In yet another embodiment, the central flex section includes a series of inner slots that provide the central flex section with a degree of flexibility. The inner slots may include a series of horizontally extending, vertically spaced openings in the central flex section of the front shell.
The cushion may enhance the localized comfort characteristics of the back support. In one embodiment, the cushion includes a central cushion section having a series of convolutions. The central cushion section may be positioned above the lumbar region of the back support to provide enhanced comfort to a thoracic region of the user.
These and other objects, advantages, and features of the invention will be more fully understood and appreciated by reference to the description of the current aspects and the drawings.
Before the aspects of the invention are explained in detail, it is to be understood that the invention is not limited to the details of operation or to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention may be implemented in various other aspects and may be practiced or may be carried out in alternative ways not expressly disclosed herein. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items and equivalents thereof. Further, enumeration may be used in the description of various aspects. Unless otherwise expressly stated, the use of enumeration should not be construed as limiting the invention to any specific order or number of components. Nor should the use of enumeration be construed as excluding from the scope of the invention any additional steps or components that might be combined with or into the enumerated steps or components.
An office-type chair 10 is shown in
The back support 12 of the present invention generally defines thoracic X, and lumbar Y regions as illustrated in
In the illustrated embodiment, the back support 12 generally includes a support frame 14 connected to and extending from the base 5, a rear shell 16 mounted on the frame 14, a front shell 18 attached to the rear shell 16, a cushion 20 positioned in front of the front shell 18, and a cover 22 covering the cushion 20. A vertically adjustable lumbar pad 24 may be positioned between the front 18 and rear 16 shells, and the front shell 18 may be provided with structure that enhances the user experience of the lumbar pad 24. The cover 22 may be a fabric upholstery with a portion that is inserted between the front 18 and rear 16 shells.
As shown in
The support frame 14 may be formed from a variety of materials, such as a cast metal or an injection molded plastic; and the vertical post 28 and lateral posts 34, 36 may be formed integrally from a single piece of molded plastic. In one embodiment, the entire support frame 14 is molded as a unitary piece, with portions of the support frame 14 molded to predetermined dimensions that will provide the overall back support 12 with a desired support profile when the support frame 14 is combined with the back support components as described below.
The rear shell 16 is mounted on the support frame 14 and forms a support and attachment structure for the front shell 18. In one embodiment, the rear shell 16 is a molded plastic shell extending through the lumbar X and thoracic Y regions of the back support 12 and having a front surface 56, a rear surface 58 and a perimeter edge 60 having a top edge 62, lateral edges 64, 66, and a bottom edge 68. The rear surface 58 is generally convex and faces the support frame 14. The front surface 56 is generally concave, and faces away from the support frame 14.
The rear shell 16 may have a variety of integrally molded features for providing support and for attaching to the various back support components. With reference to
In one embodiment, the rear shell 16 further includes integrally molded structure for attachment to the front shell 18 and for attachment to a rear cover 80 (shown in
In one embodiment the rear shell further defines a lumbar slot 100 positioned in the lumbar region Y and generally centrally located along the lateral extent of the rear shell 16. The lumbar slot 100 may have a vertical extent that spans substantially all of the vertical extent of the lumbar region Y, the lumbar slot 100 including an upper end 102 and a lower end 103. In one embodiment, the upper end 102 is positioned vertically below the lateral attachment openings 70, 72. An upper fastener hole 73 may be included above the lumbar slot 100.
The front shell 18 attaches to the front surface 56 of the rear shell 16. The front shell 18 may be a molded plastic shell, and in the illustrated embodiment includes a front surface 110, a rear surface 112, and a perimeter edge 114. The shape of the front shell 18 and extent of the perimeter edge 114 may correspond to that of the rear shell 16, such that the perimeter edges 60, 114 of the respective shells are coterminous. The perimeter edge 114 of the front shell 18 may include a top edge 116, left and right side edges 118, 120, and a bottom edge 122.
Referring to
In one embodiment, the front shell 18 further includes a central flex section 200. The central flex section 200 is a section of the front shell 18, located generally in a laterally central position in the lumbar region of the front shell 18, that provides a degree of movement with respect to the remainder of the front shell 18, and may further provide a greater degree of flexibility than the remainder of the front shell 18. Referring to
As noted, the central flex section 200 can also be configured to be more flexible than the remainder of the front shell 18. As shown in
In one embodiment, the back support 12 includes a vertically adjustable lumbar pad 24 positioned between the front 18 and rear 16 shells, and the front shell 18 may be provided with structure that enhances the user experience of the lumbar pad 24. Referring to
In one embodiment, the lumbar track 252 is a generally vertically extending ring having a front surface 280, a rear surface 282, a perimeter edge 283, and defining a vertically extending slot 284. The lumbar track 252 may be formed from plastic, and may be sized and shaped to fit into the lumbar slot 100 of the rear shell 16 with perimeter edge 283 at the front surface 280 of the track 252 being at least slightly larger than the opening of the lumbar slot 100 in order to cover the lumbar slot opening 100. The vertical extent of the track slot 284 may be generally aligned with the vertical extent of the lumbar slot 100 in the rear shell. In one embodiment, a right detent bar 290 and a left detent bar 292 extend from the front surface 280 spaced inwardly from the perimeter edge 283. The detent bars 290, 292 may project at least partially through the lumbar slot 100 in the rear shell 16. As illustrated, the left and right detent bars 290, 292 include opposing, facing surfaces 294 having vertically spaced apart notches or detents 298 for selectively receiving the knobs 269 of the flex fingers 265, 267 of the carriage 250 as described in more detail below. The track 252 may include one or more features for attaching the track 252 to the rear shell 16 and the support frame 14. As illustrated, the track includes a securement boss 253 at an upper end and a pair of securement openings 255 at a lower end.
The lumbar handle 254 attaches to the lumbar carriage 250 through the slot opening 284 in the track 252 such that the lumbar handle 254 and the lumbar carriage 250 travel in unison. Referring to
In one embodiment, shown, for example, in
The cushion 20 is positioned between the front shell 18 and the cover 22, and provides an added degree of comfort and support for a user. The cushion 20 may further be constructed to cooperate with the front shell 18 and the lumbar pad 24 to provide coordinated support characteristics for the back support 12. In the illustrated embodiment, the cushion 20 is a molded foam having a front foam surface 340, a rear foam surface 342 and a foam perimeter edge 344. The rear foam surface 342 faces and may abut the front surface 110 of the front shell 18. The foam perimeter edge 344 may be coterminous with that of the front shell 18 such that the cushion 20 fits onto the front surface 110 of the front shell 18. The cushion 20 has a thickness between the front 340 and rear 342 foam surfaces that is sufficient to provide the user with a desired degree of support.
Referring to
As shown in
In one embodiment, the back support 12 additionally includes a rear cover 80. Shown, for example, in
Assembly of the back support 12 generally includes forming the rear shell 16 and the front shell 18, for example, by molding the shells 16, 18 from a thermoplastic material. Formation of the rear shell 16 may include the step of integrally molding the variety of molded features of the rear shell 16, including the lateral openings 70, 72 and the bottom opening 74 for attachment of the rear shell 16 to the support frame 14, and molding in the attachment structure for attachment to the front shell 18 and the rear cover 80, such as the hook receptacles 82 and the snap posts 84 for tool-less attachment to the front shell 18, the support ribs 92, the one or more drawstring guides 96, and the lumbar slot 100. As noted above, in one alternative embodiment, the lumbar track 252 may also be molded integrally with the rear shell 16.
Formation of the front shell 18 can be competed in a similar manner, via molding the front shell 18 from a thermoplastic material. The molding of the front shell 18 may include the integral formation of the variety of molded in front shell 18 components, including the series of hooks 124 and snap receptacles 126 for attaching to the rear shell 16, and the front shell may include drawstring posts 140 for routing and retaining the drawstring 390 of the cover 22. The front shell 18 may additionally be molded to include a central flex section 200, including the molding of the series of connector webs 212 connecting the central flex section 200 to the remainder of the front shell 18, and the vertical 225 and horizontal 223 strips that provide the central flex section with internal flexibility.
The cushion 20 is positioned in front of the front shell 18 with the foam perimeter edge 344 of the cushion 20 aligned with the perimeter edge 114 of the front shell 18 and the rear foam surface 342 of the cushion 20 facing the front surface 110 of the front shell 18. In the illustrated embodiment, wherein the cushion 20 includes a convoluted section 350, the convoluted section 350 is positioned to be aligned substantially above the central flex section 200 of the front shell 18, although other arrangements between the flex section and convoluted section are possible, depending on the desired support characteristics of the back support 12.
With the cushion 20 in place, the cover 22 is attached to the front shell 18 over the cushion 20. In the illustrated embodiment, the cover 22 is attached to the front shell 18 by placing the rear surface 372 of the central cover region 374 of the cover 22 over the cushion 20, wrapping the perimeter region 376 around the perimeter edge 114 of the front shell 18, and positioning the insertion portion 398 on the rear surface 112 of the front shell 18 with the drawstring 390 routed around the drawstring posts 140. The drawstring 390 may be drawn tight, to tighten the cover 22 on the front shell 18, and tied off or attached to the front shell 18, for example, with a fastener or a series of fasteners, to hold the drawstring 390 and cover 22 in place. In a similar manner, the rear cover 80 may be placed over the rear surface 58 of the rear shell 16, with the perimeter region 410 wrapped around the rear shell 16, and the insert portion 412 positioned against the front surface 56 of the rear shell 16. A drawstring (not shown) on the rear cover 80 may be routed about the drawstring guides 96 on the rear shell 16 and tied or attached to the rear shell 16 to secure the rear cover 80 in place.
The lumbar pad 24 and carriage 250 are provided between the front 18 and rear 16 shells. The lumbar pad 24 is attached to the carriage 250, for example, by inserting the tab protrusion 280 of each of the attachment fingers 276 of the carriage 250 into the attachment holes 245 on the lumbar pad 24, with the front surface 230 of the lumbar pad 24 facing the rear surface 112 of the front shell 18. The lumbar track 252 and lumbar handle 254 are provided on an opposite side of the rear shell 16, adjacent the lumbar slot 100 in the rear shell 16, and the detent bars 290, 292 of the lumbar track 252 are inserted at least partially through the lumbar slot 100. The lumbar track 252 may be attached to the rear shell 16, for example, by the fastener 500 extending through the securement boss 253 on the track 252 and the fastener hole 73 on the rear shell 16, and a pair of the fasteners 52 extending through the securement openings 255 and the fastener holes 74 on the rear shell 16 with the track 252 also forming a cover for the opening 404 in the rear cover 80.
With the track 252 secured in place on the rear shell 16 adjacent to the rear surface 58 of the rear shell 16, the carriage 250 is positioned adjacent to the lumbar slot 100 on the front surface 56 of the rear shell 16 and attached to the handle 254 through the lumbar slot 100 and the track slot 284 via fasteners 306 extending through the attachment holes 270 in the spine 264 of the carriage 250 and the securement holes 303 in the central attachment section 300 of the handle 254. In this position, each of the knobs 269 on flex fingers 265, 267 on the carriage 250 can interfit with a corresponding detent 298 in the detent bars 290, 202 of the track 252.
The front 16 and rear 18 shells are connected to one another via the mating attachment structure on the shells 16, 18. More particularly, the front shell 18 can be attached to the rear shell 16 by aligning the rear surface 112 of the front shell 18 with the front surface 56 of the rear shell 16, with the hooks 124 of the front shell 18 aligned with the hook receptacles 82 of the front shell 18, and with the snap receptacles 126 of the front shell 18 aligned with the snap posts 84 of the rear shell 16. The hooks 124 may then be inserted into the hook receptacles 82 by inserting the upwardly extending second legs 130 of each of the hooks 124 into an associated one of the open bottom edges 86 of each of the hook receptacles 82. The snap posts 84 and snap receptacles 126 may then be snap-fit together by inserting the head 90 of each of the snap posts 84 into and through the retention ring 132 of each of the snap receptacles 126. As shown in FIG. 2, the insertion portion 398 of the cover 22, and the insertion portion 412 wrap around the respective shells 16, 18 and abut each other between the shells 16, 18. In another embodiment, a different securement method may be used for connecting the front 18 and rear 16 shells, such as a series of fasteners or an alternative fastener-less structure.
The rear shell 16 is supported on the support frame 14 to fully assemble the back support 12. As shown, for example, in
As an occupant or user sits on the seat support 3 of the chair 10, the occupant receives support from the back support 12. Each of the front shell 18 and the rear shell 16 may have a degree of flexibility to curve around the occupant as the occupant engages the back support 12. The cushion 20 provides an added layer of comfort and support, with the convoluted section 350 providing an enhanced degree of comfort in the occupant's thoracic region (above the lumbar region). The central flex section 200 may provide increase support and comfort characteristics, as the central flex section 200 moves with respect to the remainder of the front shell 18 due to the spaced apart connector webs 212 and the absence of connector webs 212 between the upper edge 204 of the central flex section 200 and the remainder of the front shell 18. The lumbar pad 24 may be vertically adjusted by an occupant providing a vertical force on the lumbar handle 254, causing the flex fingers 265, 267 to flex and selectively engage the detents 298 on the track 252. As the lumbar pad 24 is adjusted, the front surface 230 of the lumbar pad 24 may engage the lumbar enhancement ribs 320 on the front shell 18. The gradual increase in rib height of the lumbar enhancement ribs, combined with the flexibility of the central flex section 200 from which the lumbar enhancement ribs 320 extend, can increase the amount that the occupant feels and is supported by the lumbar pad 24 as the lumbar pad 24 is moved vertically upwardly. Notably, in another embodiment, the back support 12 may not include the lumbar pad 24, and in such an embodiment the lumbar slot 284 and lumbar pad accessories may be eliminated.
In summary, the support characteristics of the back support 12 may be tuned to a desired profile by varying the features of the back support 12, such as the flexibility of the front 18 and rear 16 shells, the number and positioning of the connector webs 212, the positioning and spacing of the inner slots 220 of the central flex section 200, and the size and positioning of the central flex section 200 and the convoluted section 350 of the cushion 20. The support characteristics of the lumbar pad 24 can be varied by adjusting the flexibility and shape of the pad 24, and the size and positioning of the lumbar enhancement ribs 320. Combinations of modifications to the individual components results in highly customizable support characteristics available to design into the office chair.
The above description is that of current embodiments of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. This disclosure is presented for illustrative purposes and should not be interpreted as an exhaustive description of all embodiments of the invention or to limit the scope of the claims to the specific elements illustrated or described in connection with these embodiments. For example, and without limitation, any individual element(s) of the described invention may be replaced by alternative elements that provide substantially similar functionality or otherwise provide adequate operation. This includes, for example, presently known alternative elements, such as those that might be currently known to one skilled in the art, and alternative elements that may be developed in the future, such as those that one skilled in the art might, upon development, recognize as an alternative. Further, the disclosed embodiments include a plurality of features that are described in concert and that might cooperatively provide a collection of benefits. The present invention is not limited to only those embodiments that include all of these features or that provide all of the stated benefits, except to the extent otherwise expressly set forth in the issued claims. Features of various embodiments may be used in combination with features from other embodiments. Directional terms, such as “vertical,” “horizontal,” “top,” “bottom,” “front,” “rear,” “upper,” “lower,” “inner,” “inwardly,” “outer,” “outwardly,” “forward,” and “rearward” are used to assist in describing the invention based on the orientation of the embodiments shown in the illustrations. The use of directional terms should not be interpreted to limit the invention to any specific orientation(s). Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular.
