Title:
GLIDER
Kind Code:
A1


Abstract:
A glider has a chair frame that provides support to a seat and back rest. The frame includes a glider structure that is connected to each side frame member and includes a glider rail and a first and second elongate arcute glider tracks, a first and second wheel assembly, where the glider rail is attached to the backrest and the seat and enables gliding movement of the backrest and seat as the wheel assembly moves through a curved profile in the glider track. The glider chair can also be part of a modular system of components that enable one or more seating units to be in a spanned or ganged configuration.



Inventors:
Grabowski, Daniel (Grand Rapids, MI, US)
Heyder, John Henry (Orleans, IN, US)
Foreman, Jeremy Franklin (Bedford, IN, US)
Johnson, Michael A. (Burlington, IA, US)
Schradin, Aaron Jon (Holland, MI, US)
Application Number:
11/556442
Publication Date:
05/17/2007
Filing Date:
11/03/2006
Assignee:
HNI TECHNOLOGIES INC. (Muscatine, IA, US)
Primary Class:
International Classes:
A47C3/02
View Patent Images:
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Primary Examiner:
TANG, JEFF
Attorney, Agent or Firm:
Faegre Drinker Biddle & Reath LLP (MINNEAPOLIS, MN, US)
Claims:
1. A glider chair comprising: a chair frame comprising front and rear frame members, and two parallel side frame members, each side frame member attachable to the front and rear members; a seat supported by at least two frame members; a backrest supported to at least one frame member; a pair of legs wherein at least two frame members are connected to the legs; and a pair of glider structures connected to each side frame member comprising a glider rail and a first and second elongate arcute glider tracks, a first and second wheel assembly, wherein the glider rail is attached to the backrest and the seat and enables gliding movement of the backrest and seat as the wheel assembly moves through a curved profile in the glider track.

2. The glider chair of claim 1 wherein the backrest includes a backrest support structure.

3. The glider chair of claim 1 wherein the chair further comprises cross tubes and cross tube couplers for maintaining dimensional spread, providing additional structural rigidity and multiple widths.

4. The glider chair of claim 1 wherein the wheel assembly comprises a wheel.

5. The glider chair of claim 4 wherein the wheel assembly comprises a wheel bearing.

6. The glider chair of claim 1 wherein the glider track comprises a top inner edge chamfer and a bend in the glider rail.

7. The glider chair of claim 1 wherein the glider tracks are a larger in height than the diameter of the wheel assembly and a upper and lower bearing surfaces of the tracks are upwardly curved with a constant radius of curvature and the upper and lower bearing surfaces are parallel to each other.

8. The glider chair of claim 1 wherein the first and second glider tracks lie in the same plane comprising a series of concentric radii R1 to R2.

9. The glider chair of claim 1 wherein the front and rear members include front, rear and bottom glider covers that fit over the glider assembly.

10. The gliding chair of claim 1 wherein the glider is part of a modular system.

11. The gliding chair of claim 9 wherein the one or more chair gliders are assembled in a spanned configuration or a ganged configuration.

Description:

CLAIM OF PRIORITY

This application claims priority from U.S. provisional application Ser. No. 60/733,864, filed Nov. 3, 2005, entitled “Glider,” and from U.S. provisional application Ser. No. 60/733,866, filed Nov. 4, 2005, entitled “Modular Furniture Construction,” both incorporated herein by reference.

BACKGROUND OF THE INVENTION

The invention relates generally to chairs and more specifically to chair with a compact glider mechanism. It is desirable in some environments, particularly in lobbies of seating that is comfortable to the user. Additionally, it is important that any options or features that add to the comfort be incorporated into the chair construction in a way that minimizes the number of parts and maximizes the use of common parts among different options, maximizes efficiencies of manufacturing and assembling, maximizes ease of adjustment and yet that results in a visually pleasing design.

SUMMARY OF THE INVENTION

One embodiment of the invention includes a glider chair that includes:

    • a chair frame comprising front and rear frame members, and two parallel side frame members, each side frame member attachable to the front and rear members;
    • a seat supported by at least two frame members;
    • a backrest supported to at least one frame member;
    • a pair of legs wherein at least two frame members are connected to the legs; and
    • a pair of glider structures connected to each side frame member comprising a glider rail and a first and second elongate arcuate glider tracks, a first and second wheel assembly, wherein the glider rail is attached to the backrest and the seat and enables gliding movement of the backrest and seat as the wheel assembly moves through a curved profile in the glider track.

Another embodiment of the invention includes a glider that can be part of a modular system.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will hereinafter be described in conjunction with the appended drawing figures wherein like numerals denote like elements.

FIG. 1a is a perspective view of a fully-assembled chair;

FIG. 1b is an exploded perspective view of a chair, in which the seat, seat cushion and backrest cushion have been removed;

FIG. 2 is a perspective view thereof, in which the seat and backrest cushions are translucent in order to show the internal parts of the chair;

FIG. 3 is a perspective view thereof, in which the seat cushion, backrest cushion and seat panel have been removed;

FIG. 4 is a perspective view thereof, in which the front, rear and bottom glider covers have been removed;

FIG. 5 is an enlarged partial sectional view taken along line 5-5 of FIG. 4 in which the center cross-tubes are removed;

FIG. 6 shows an further-enlarged partial view of FIG. 5;

FIG. 7 is a partial sectional view taken along line 7-7 of FIG. 4; and

FIG. 8 is an enlarged partial view of the glider track and wheel shown in FIG. 7.

FIG. 9 is a partially exploded perspective view of a glider chair, in which the glider frame, covers, seat, seat cushion and backrest cushion have been removed;

FIG. 10 is a partially exploded perspective view of a glider chair, in which the glider covers and supports are removed and the seat cushion is shown translucently in order to show the internal parts of the chair;

FIG. 11 is partially exploded perspective view of two chair units arranged in a spanned configuration;

FIG. 12 is partially exploded perspective view of two chair units and a loveseat unit arranged in a ganged configuration;

FIG. 13 is a perspective view of the chair shown in FIG. 1, shown with an IV stand attached to the right arm;

FIG. 14 is an enlarged view of the portion of FIG. 14 shown in area 14-9;

FIG. 15 is a perspective view of the chair shown in FIG. 1, shown with a plug covering the exterior holes in the right arm; and

FIG. 16 is an enlarged view of the portion of FIG. 15 shown in area 16-1 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The ensuing detailed description provides exemplary embodiments only, and is not intended to limit the scope, applicability, or configuration of the invention. Rather, the ensuing detailed description of the exemplary embodiments will provide those skilled in the art with an enabling description for implementing the preferred exemplary embodiments of the invention. It being understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the invention.

To aid in describing the invention, directional terms may be used in the specification to describe portions of the present invention (e.g., upper, lower, left, right, etc.). These directional terms are merely intended to assist in describing and claiming the invention and are not intended to limit the invention in any way. In addition, reference numerals that are introduced in the specification in association with a particular drawing figure may be repeated in one or more other figures without additional description in the specification, in order to provide context for other features.

FIGS. 1a and 1b shows an embodiment of a chair 10 of the present invention, which includes two support members 12 and 14, a backrest 16 and a seat 18. The support members 12 and 14 are preferably made of wood, but could be made of other structurally suitable metallic or polymer materials and may be covered with other hard or soft materials. The support members 12 and 14 may be a common part, providing economies of scale and ease of manufacturing or they may have differing features depending upon the intended functionality of the final product. In either case, the support members 12, 14 provide an attachment point for the frame 32, which is described in greater detail herein. The support arms 12, 14 provide the legs, armrest and structure for the mounting of the seat 18.

If the support members 12, 14 are a common part, the mounting holes 15 on the outer side of each of the arms 12, 14 are preferably arranged in the same configuration as the inner mounting holes 13. If the support members 12, 14 are provided in left and right versions, mounting holes 15 on the outer side of each support member 12, 14 may be provided in a different configuration than the inner mounting holes 13, or may be omitted. If the support members 12, 14 are provided in left and right versions, a center version (see arms 112, 114, FIG. 12) having mounting holes 15 on the outer side of each of the support members 12, 14 arranged in the same configuration as the inner mounting holes 13, is preferably provided for use in ganging configurations (defined below).

The backrest 16 is best shown in FIG. 2. Its components include a backrest cushion 20 and a backrest support structure 22. In this embodiment, the backrest cushion 20 is shown as a fabric cover over a foam core, but could alternatively comprise other suitable materials, such as wood, polymer, vinyl, leather, for example. The backrest support structure 22 consists of two side panels 24 and 26, a top rail 28 and a bottom rail 30. Two filler pieces not shown may optionally be included with the side panels 24 and 26. The filler pieces are generally rectangular in cross section and have a length approximately equal to the slot in the lower portion of the side panels 24 and 26. The filler pieces provide increased bearing area for the slots and, if necessary, fill a gap between the side panels 24 and 26 and any mating components. In the case of the wood version shown, these components are assembled and the fastened with conventional techniques, such as slots or grooves in the mating pieces, mechanical fasteners or adhesives. The backrest cushion 20 is attached to the backrest support structure 22 with conventional means.

In some embodiments of the invention, the backrest 16 is secured to the arms 12, 14 via right and left backrest brackets 54, 55, respectively. Each of the backrest brackets 54, 46 includes a mounting flange 57, which includes holes formed therein that line up with at least two of the inner holes 13 on the arm 12, 14 to which it is to be attached using screws, bolts or other suitable attachment means. Each of the brackets 54, 46 also includes a backrest flange 69 which slides into a complimentary slot 61 formed in the backrest 16. Any suitable means, such as a screw, may be used to prevent the backrest flange 59 from being removed from the slot 61.

Referring now to FIGS. 3 and 4, the frame 32 includes right and left side frame members 34, 36 and front and rear frame members 40, 46, which are preferably welded together. The frame 32 provides the primary structural support for the seat 18 and backrest 16, as well as attachment points for components of the seat 18. The front and rear frame members 40, 46 each include mounting flanges 42, 48 at each end for mounting the frame 32 to the arms 12, 14. The side members 34, 36 and the front and rear frame members 40, 46 are preferably of tubular metallic construction. The front and rear flanges 42 and 48 are made from metallic bars and include holes for attaching the frame 32 to the arms 12 and 14. The left side frame member 36 preferably includes holes, or other attachment points, for enabling the left glider track 68 (FIG. 4). The right side frame member 34 is a mirror image of the left side frame member 36 and includes the same features.

The seat 18, shown in FIGS. 1 and 2, is, in this embodiment, comprised of a seat cushion 50 (described above) and a seat panel 52. The seat panel 52 is made of sheet material (such as plywood) suitable to provide support for the weight of the seated user as well as a means of general attachment for the seat 18.

The frame 32 shown in FIGS. la and lb is 24 inches in width (from arm 12 to arm 14). Other frame widths could be provided for alternative embodiments, such as 20, 32 or 40 inch frames widths.

Referring now to FIGS. 3-5, the glider structure includes right and left glider rails 54 and 56, a left glider track 68, front , center and rear cross tubes 70, 74 and 78, cross tube couplers 72, 76 and 80, a front wheel assembly 82, a front wheel axle 88, and front, rear and bottom glider covers 98, 99 and 100 (see FIG. 7). The details of the rear wheel assembly, rear track profile and the right glider track and components are not visible in the drawings, but it should be understood that these features are substantially similar to the front wheel assembly, front track profile, left glider track and components, respectively. That is, the rear elements of the left glider track are substantially the same as the described front elements and the right side glider elements mirror the described left side elements.

Gliding motion of the seat 18 and backrest 16 (i.e., movement of the seat 18 and backrest 16 forwardly and rearwardly) is enabled by rotation of a front wheel assembly 82 and the rear wheel (not shown) in the curved profile or track provided in glider track 68. Referring to FIG. 6, the front wheel assembly 82 is shown consisting of an elastomeric outer wheel 84 and a wheel bearing 86 for optimum ease and smoothness of operation. Alternatively, the wheel assembly 82 could be a one piece design (i.e., without a bearing). The outer wheel 84 could be metallic or polymeric in construction. An axle 88 provides the means of transforming the rotational motion of the front wheel 82 into linear motion of the left glider rail 56. The wheel axle 88 is preferably a metallic rod of appropriate diameter and strength to carry the weight of the seated user.

FIGS. 6 and 8 show detail cross sectional and plan views of the left glider track 68. The glider track 68 could be precision molded or cast or machined from metallic or polymeric materials, but in the present invention is molded of polymeric material such as ABS.

The glider track 68 is generally rectangular in cross section with details as required for specific functionality, which includes, in this case, a top inner edge chamfer 71 to provide clearance with the bend 57 in left glider rail 56, a perimeter edge cut 73 to provide clearance with glider covers (FIG. 3), a lower inside surface protrusion 75 to minimize sliding contact area and thereby friction between the left glider rail 56 and the left glider track 68, the glider track profile 77, and lastly, the glider track front attaching hole 95 to allow use of a suitable fastener such as a cap screw for attachment to the left frame side member 36.

The glider track profile 77 is preferably defined by concentric radii R1, and R2, which result in a constant track height, providing the preferred minimal clearance for the front wheel assembly 82 and the desired dual axis gliding motion. The ends of the glider track profile 77 are defined by radii R3 and R4 which are preferably equal to each other and arithmetically to (R1-R2)/2 to provide a smooth track profile. Other details of the glider track profile 77 cross section (see FIG. 6) includes a profile depth 89, a rear wall 97, a lower wheel surface 91 and an upper wheel surface 92, all providing sufficient space for front wheel assembly 82. The rear wall 97 is preferably vertical. The lower wheel surface 91 is defined by radius R1, already described, an inside contour radius R5 which is selected to complement the front wheel assembly 82 and the track depth 89. The upper wheel surface 92 is preferably perpendicular to the rear wall 97 and is defined by radius R2 and profile depth 89. The radii of curvature R1, and R2 of the lower and upper wheel surfaces 59, 60 are preferably in the range of 30-35 inches. Such curvature provides sufficient curvature so that the wheel 52 tends to return to a position at the center of the lower wheel surface 59 (referred to herein as the “neutral position”) when the user is not applying any forward or rearward forces to the seat 18 or backrest 16 and so that the wheel 52 does not bump against the front or rear end surfaces 61, 62 during normal use. In one embodiment, the upper and lower wheel surface are parallel to each and have a constant radius of curvature. During normal use the upper and lower wheel surface are fixed with respect to one another.

FIG. 7 shows the left glider track 68 and track profile 77 with the front and rear wheel assemblies 82 and 87 in the neutral position of the glider motion.

The right and left glider rails 54 and 56 shown in FIGS. 2-5 provide structural support for, and connection between, the backrest 16 and the seat 18. The left glider rail 56 and associated parts will be described with the understanding that the right glider rail 54 includes similar components and is a mirror image of the left glider rail 56.

The left glider rail 56 is preferably a single piece fabrication, cut and formed from sheet of metallic material such as 0.125-0.250 inch thick steel. Alternatively, it could be constructed as a multi-piece welded metallic structure or a single-piece molded part of appropriate strength polymer materials. The left glider rail 56 is comprised of a left lateral tab 79, a left vertical tab 81, a left horizontal leg 83 and a left vertical leg 85. Each tab and leg is orthogonal to its adjacent feature.

The left lateral and vertical tabs 79 and 81 provide the attaching structure for the backrest 16. The left lateral tab 79 slides into a correspondingly-shaped slot (not numbered in the figures) formed in the left side panel 26. A screw or other fastener is preferably provided to prevent the left side panel 26 from unintentionally disconnecting from the left lateral tab 79.

The left horizontal leg 83 of the left glider rail 56 enables attachment of the seat 18 at a key hole slot 58 and a hole 62. The attachment is accomplished with conventional fasteners, such as screws.

The left vertical leg 85 provides the front and rear mounting holes 64 and 66. The front and rear mounting holes 64 and 66 are preferably a close fit with the front and rear wheel axles 88 and 90. The left horizontal leg 83 and left vertical leg 85 share the profile of the cross tube cutout 60 and, as such, provide the mounting pocket for the end of the center cross tube 74. The left horizontal leg 83 is approximately the same length as the left frame side member 36, with a width providing full support for seat 18 and clearance for the arm 14. The left vertical leg 85 is preferably shorter in length, extending slightly past the front wheel assembly 88 and the rear wheel assembly (not shown), and preferably has a width sufficient to cover the left glider track 68. The shorter length of the left glider rail vertical leg 85 provides clearance with the frame 32 when the seat 18 is at the extremes of the gliding motion.

FIGS. 3 and 4 show the front, center and rear left cross tubes 70, 74 and 78, front center and rear cross tube couplers 72, 76 and 80 and front, center and rear right cross tubes 61, 65 and 67. The cross tubes and cross tube couplers form members that span between the right and left glider rails 54 and 56 maintaining the dimensional spread and minimizing any movement of the right and left glider rails 54 and 56 that would allow undesirable displacement of the front wheel assembly 82 or rear wheel assembly from the glider track profile 77 shown in FIG. 6. The front and rear left cross tubes 70 and 78 also provide support for the front and rear wheel axles 88 and 90 shown in FIG. 5. The cross tube couplers maintain dimensional spread, and provide additional structural rigidity and multiple widths.

The front, center and rear left and right cross tubes 70, 74, 78, 65, 67, and 69 are metallic and circular in cross section and may be identical to each other, for manufacturing simplicity and minimization of part proliferation. The corresponding front, center and rear cross tube couplers 72, 76 and 80 are also metallic, circular in cross section, and each have an inside diameter sized to just slide over the outside diameter of the mating cross tubes. Conventional metallic tubing products are available that could meet these requirements. The front, center and rear cross tube couplers 72, 76 and 80 may be attached to the corresponding cross tubes 70, 74, 78, 65, 67, and 69 by a number of conventional mechanical means, depending upon manufacturing and assembly practices and preference. In this embodiment, the couplers 72, 76 and 78 are attached to corresponding cross tubes 70, 74, 78, 65, 67, and 69 via screws and overlapping holes (not shown). In this embodiment, the front and rear cross tubes 70, 78, 65, and 69 are welded to the wheel axles 88 and the center cross tubes 67, 74 are welded to the cross tube cutouts 60.

The front and rear glider covers 98 and 99 are shown in FIG. 3, and bottom glider cover 100 is shown in FIG. 7, which fit into the glider track 68, overlap to completely close off the bottom and extend far enough in on top to provide aesthetic coverage when the seat 18 moves through the gliding motion. In this example they are shown as thin sheet metallic parts with an irregular periphery and multiple bends to provide the clearance and coverage functions desired. The material could be sheet steel of 0.031-0.093 thickness, but alternatively might be a polymer such as ABS. In this embodiment, the covers 98 and 99 are provided to prevent injury from a user's contact with the internal moving parts of the glider structure.

A preferred method of assembling the glider structure comprises assembling the right and left glider rails 54 and 56, left glider track 68, right glider track, front, center and rear cross tubes 70, 74 and 78 on the left and right sides, cross tube couplers 72, 76 and 80, the front wheel assembly 82, front wheel axle 88, as well as the left rear and right front and rear wheel and axle assemblies, then moving the entire glider structure into position in the frame 32 and attaching the left glider track 68 and right glider track to the frame 32.

Embodiments of the present invention also include a modular system of components that enable one or more seating units to be assembled in a spanned configuration or a ganged configuration using the same parts as are used for each unit when assembled in a single-unit configuration. See U.S. provisional application Ser. No. 60/733,866, incorporated herein by reference. As used herein, a “spanned” configuration refers to a furniture configuration in which multiple frames are joined without arms located between the joined frames (see FIG. 11). In a spanned configuration, the two arms are located at each end. As used herein, a “ganged” configuration refers to a furniture configuration in which multiple frames are joined with arms located between each of the joined frames (see FIG. 12). In a ganged configuration, the number of arms is usually one greater than the number of joined frames in the configuration.

As used herein, the term seating “unit” refers to any furniture items that can be assembled in a single-unit configuration, most often with a single-piece frame. The parts and single-configuration assembly for each of these seating units are briefly described herein.

A spanned configuration comprising two chair units 110 and 111 is shown in FIG. 11. This configuration includes two frames 132, 133 which are jointed by bolting their adjoining front flanges 142, 143. As in the chair embodiment (FIG. 1), the outer ends of the frames 142, 143 are bolted to right and left arms 112, 114. A center backrest bracket 155 is bolted between the rear flanges 148, 149 and provides an attachment point for the right backrest 116 and the left backrest (not shown). The center backrest bracket 155 includes two opposing backrest flanges 162, 163. In this embodiment, the left backrest is identical to the right backrest 1 16. As in the chair embodiment, a right backrest bracket (not shown) and a left backrest bracket 156 are attached to the right and left arms 112, 114, respectively, and the backrests are, in turn, attached to the backrest brackets. In order to provide additional stability, a center leg 170 may be located between the frames 132, 133 and affixed thereto using any suitable means of attachment, such as a bolt or pin, for example. Alternatively, a single, wider backrest (see e.g., FIG. 12) could be used an the spanned configuration instead of two backrests. In order to provide even spacing between the frames 132, 133 from front to rear, a spacer (not shown), equal in width to the portion of the center backrest bracket 155 located between the rear flanges 148, 149, may be provided between the front flanges 142, 143.

As should be evident from comparing FIGS. 1-2 with FIG. 11, many of the components of the spanned configuration are the same as those used in single unit chairs 10. The frame 32, arms 12, 14, backrest 16, backrest brackets 54, 57 and seat 18 used in the stationary chair 10 can be the same as the corresponding parts used in the spanned configuration. In this embodiment, the only parts that are unique to the spanned configuration are the center leg 170, the center backrest bracket 155 and the optional spacer located between the front flanges 142, 143.

The spanned configuration shown in FIG. 11 could incorporate frames of different lengths. When using a glider unit (FIGS. 9, 10) as part of a spanned configuration more than two frames is not recommended, due to the additional lateral and dynamic stress associated with the glider units.

A ganged configuration of the present invention is shown in FIG. 12, which comprises two chair units 210, 211 and a seat unit 217, which includes a single 40-inch wide frame 238. The seat unit 217 can accommodate either two 20-inch seats or a single 40-inch seat. As shown in FIG. 12, a ganged configuration is constructed by having adjoining units share a single arm. In this embodiment, two center arms 280, 281 are provided. The right chair frame 232 is attached to the out side of the right center arm 280 and the right end of the double-seat frame 238 is attached to the inner side of the right center arm 280. Similarly, the left chair frame 233 is attached to the out side of the left center arm 281 and the left end of the double-seat frame 238 is attached to the inner side of the left center arm 281.

Left and right arms 212, 214 are attached to the outer ends of the right and left frames 232, 233, respectively. In this embodiment, the left and right arms 212, 214 are identical to the center arms 280, 281 (i.e., having mounting holes on both sides). This would allow for additional part efficiency. Alternatively, the left and right arms 212, 214 could have mounting holes only on their inner sides.

The two chair units 210, 211 include backrests 216, 217, backrest brackets 251, 253, 254, 257 and seats (not shown), which are the same as the corresponding parts used in the single unit chair 10. The frames 232, 233 and arms 212, 214 are also preferably the same as the corresponding parts in the single chair 10. Similarly, the double-seat unit 217 uses the same frame 238, backrest 219, backrest brackets, seat (not shown) as in a single unit double seat (not shown).

Many other possible ganged configurations are possible, including, but not limited to, recliner or glider units, ganging more than three frames, providing right-angle corner frames.

FIGS. 13-16 show optional uses of the mounting holes 315 on the outer sides of the arms 312, 314. FIGS. 13-14 show an IV pole 380 attached to the right arm 312 by two mounting brackets 382, 383, which are secured to arm 312 at the mounting holes 315 by screws 384. The IV pole 380 shown in FIGS. 13-14 is merely intended to be exemplary of the multitude of accessories that could be attached to the arms 312, 314, such as magazine racks, drain bags, trays, or flexible lighting, for example.

FIGS. 15-16 shows a cover 387 which can be used to cover the mounting holes 315 when they are not being used to support accessories. Each cover 387 preferably spans two mounting holes 315 and includes a tapered plug 385 for each covered mounting hole 315. The cover 387 prevents debris and other foreign objects from damaging the mounting holes 315, as well as providing an attractive appearance and space to display a product name or other trademark thereon.

While the principles of the invention have been described above in connection with preferred embodiments, it is to be clearly understood that this description is made only by way of example and not as a limitation of the scope of the invention.