Cross-reference to Related Applications

[0001] This application claims priority to United States Patent Application Serial No. 14/089,461, entitled CHAIR, filed on November 25, 2013; which claims priority to and the benefit of U.S. Provisional Patent Application Serial No. 61/729,973, entitled CHAIR, filed on November 26, 2012; each of which are hereby incorporated by reference in their entireties.

BACKGROUND

Field of the Invention

[0002] This application is generally directed towards chairs and, in particular, to stackable chairs.

Description of Related Art

[0003] Conventional chairs typically include a chair seat and a backrest, and are commonly used by one person. Chairs also often have legs to support the seat above the floor.

[0004] Chairs may be constructed from a wide variety of materials such as wood, metal, and molded plastic. Conventional chairs may have a wide variety of designs depending on factors such as intended use, ergonomics, and appearance. In addition, known chairs may have various functional considerations such as size, weight, durability, and desired seating position.

[0005] Chairs may include padding and/or may be constructed from flexible materials, such as wicker, which may make the chair more comfortable to use. Additionally, some chairs may include contoured chair seats and/or backrests for increased comfort of the user.

[0006] Some chairs may be designed to nest with other similar chairs to form an orderly group of chairs that may be conveniently transported and/or stored. Chairs designed to nest with other chairs may be referred to as "stacking chairs" or "stackable chairs" and these chairs are frequently used in assembly halls, banquet halls, convention centers, hotels, schools, churches, and other locations where large groups of people meet. When needed for seating, stackable chairs may often be positioned in an assortment of different configurations and used in a variety of settings. When the stackable chairs are no longer needed for seating, they may be stacked for easy transportation and/or storage.

[0007] Because a considerable number of chairs may be needed for a gathering, the volume required to store the chairs may be quite large even when the chairs are stacked together. This large storage volume may be problematic for business or facilities such as hotels, schools, and churches. The large storage volume may also be problematic for manufacturers, wholesalers, retailers, and consumers because a significant number of chairs may have to be stored, transported, and/or displayed.

BRIEF SUMMARY

[0008] A need therefore exists for a chair that eliminates the above-described disadvantages and problems.

[0009] One aspect is a chair that may include a chair seat and a chair back or back rest. A frame may connect the chair seat and the back rest. The frame may be attached to the chair seat and/or the back rest by one or more fasteners; a friction, interference and/or snap fit connection, and/or other suitable means. The frame may include legs that support the chair seat and back rest at the desired height.

[0010] Another aspect is a chair that may include a frame with multiple interfacing portions. Each interfacing portion may include a receiving surface and a receivable surface. The receiving surface may have a shape that is sized and configured to accept, abut, at least partially contact, engage and/or placed at least adjacent a surface having substantially the same shape as the corresponding receivable surface. An offset may separate the receivable surface and the receiving surface. The receiving and receivable surfaces of the multiple interfacing portions may be oriented such that a profile of each interfacing portion presented to the sides of the chair may be larger than the offset.

[0011] Still another aspect is a chair that may include a frame with multiple interfacing portions. The interfacing portions may have a cross-section substantially in the shape of a parallelogram. The cross-section may include a first side associated with the offset.

[0012] Yet another aspect is a chair that may include a frame with multiple interfacing portions. The multiple interfacing portions may have a profile with a length at least substantially equal to or greater than one-hundred-thirty percent (130%) of the offset and at least substantially equal to or less than one-hundred-fifty percent (150%) of the offset of the multiple interfacing portions.

[0013] A further aspect is a chair that may include a frame with multiple interfacing portions. Each interfacing portion may include a receiving surface and a receivable surface. The receivable surface may be planar and/or the receiving surface may be planar, if desired.

[0014] A still further aspect is a chair that may be at least partially constructed from tubing and the tubing may have a generally parallelogram-shaped configuration. Advantageously, the tubing may have a profile of about 0.875 in. (7/8 in.) but the generally parallelogram-shaped configuration may allow the chair to have a stacked height generally equal to or smaller than a conventional chair constructed with tubing having a rectangular configuration with a profile of about 0.625 in. (5/8 in.). [0015] Another further aspect is a chair that may include a frame with two side rails. The two side rails may be integral, one-piece structures and each side rail may be a continuous structure. The frame may also include a continuous rear leg support and the rear leg may be an integral, one-piece structure.

[0016] Yet another further aspect is a chair that may include a mono or one-piece seat. In particular, the chair seat and back rest may be integrally formed from blow- molded plastic as part of a unitary, one-piece structure. The chair may also include two interlocking portions of the frame, which may interlock, to support the front and back of the chair. Additionally, the plastic seat and frame may interlock to support the chair as part of a one-piece structure.

[0017] Another aspect is a chair that may be configured to nest with a like chair, and the chair may comprise a backrest, a seat, and a frame sized and configured to support the backrest and the seat. The frame may comprise a plurality of interfacing portions and each interfacing portion may comprise a receivable surface, a receiving surface having a shape configured to accept a surface having substantially the same shape as the receivable surface, an offset separating the receivable surface and the receiving surface, and a profile having a length larger than the offset. Each of the interfacing portions may include a cross-section substantially in the shape of a parallelogram. In addition, the cross-section may include a first side associated with the offset. If desired, the profile may have a length equal to or greater than one -hundred-thirty percent (130%) of the offset and equal to or less than one -hundred-fifty percent (150%) of the offset. Additionally, the receivable surface may be planar and/or the receiving surface may be planar. The frame may also be sized and configured to form a plurality of legs and each leg may include an interfacing portion of the plurality of interfacing portions. The plurality of legs may include a first front leg, a second front leg, a first rear leg, and a second rear leg. The first front leg and the second front leg may be oriented at an angle being equal to or greater than about four degrees from vertical and equal to or less than about ten degrees from vertical. The first rear leg and the second rear leg may be oriented at an angle being equal to or greater than about twenty degrees from vertical and equal to or less than about thirty degrees from vertical. Also, at least one of the seat and the backrest may be formed from blow-molded plastic. Further, the frame may include a hollow metal tube having a cross-section substantially in the shape of a parallelogram having a side substantially equal in length to the offset.

[0018] Still another aspect is a frame that may comprise a plurality of interfacing portions and each interfacing portion may comprise a receivable surface, a receiving surface having a shape configured to accept a surface having substantially the same shape as the receivable surface, an offset separating the receivable surface and the receiving surface in a first direction, a profile in the first direction, and the profile may have a length larger than the offset. The frame may further comprise a hollow metal tube. If desired, the hollow metal tube may have a cross-section substantially in the shape of a parallelogram. In addition, the cross-section may include a first side substantially equal in length to the offset. The cross-section may further include a second side associated with the receiving surface and a third side associated with the receivable surface. Additionally, the frame may comprise a plurality of legs and each of the plurality of legs may include at least one interfacing portion of the plurality of interfacing portions. The plurality of legs may include a first front leg, a second front leg, a first rear leg, and a second rear leg; the first front leg and the second front leg may be oriented at an angle being equal to or greater than about four degrees from vertical and equal to or less than about ten degrees from vertical; and the first rear leg and the second rear leg may be oriented at an angle being equal to or greater than about twenty degrees from vertical and equal to or less than about thirty degrees from vertical.

[0019] Yet another aspect is a chair that may be configured to nest with a like chair and the chair may comprise a backrest formed at least in part from blow-molded plastic, a seat formed at least in part from blow-molded plastic, and a frame including plurality of legs formed at least in part from hollow metal tubes having a cross-section substantially in the shape of a parallelogram. Each of the legs may include an interfacing portion comprising a substantially planar receivable surface associated with a first side of the hollow metal tubes, a substantially planar receiving surface associated with a second side of the hollow metal tubes, the second side opposite the first side, an offset associated with a third side of the hollow metal tubes, and a profile associated with an overall thickness of the hollow metal tubes in the direction of the offset, the profile having a length larger than a length of the offset

[0020] These and other aspects, features, and advantages of the present invention will become more fully apparent from the following brief description of the drawings, the drawings, the detailed description of preferred embodiments, and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The appended drawings contain figures of preferred embodiments to further illustrate and clarify the above and other aspects, advantages, and features of the present invention. It will be appreciated that these drawings depict only preferred embodiments of the invention and are not intended to limit its scope. Additionally, it will be appreciated that while the drawings may illustrate preferred sizes, scales, relationships, and configurations of the invention, the drawings are not intended to limit the scope of the claimed invention. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

[0022] Figure 1 A is a front perspective view of an exemplary chair;

[0023] Figure IB is a rear perspective view of the chair shown in Figure 1 A;

[0024] Figure 1C is a front view of the chair shown in Figure 1A;

[0025] Figure ID is a side view of the chair shown in Figure 1A;

[0026] Figure IE is a top view of the chair shown in Figure 1A;

[0027] Figure IF is a bottom view of the chair shown in Figure 1A;

[0028] Figure 1G is a rear view of the chair shown in Figure 1A;

[0029] Figure 2A is a partially exploded front perspective view of an exemplary stack of chairs, the chairs having a configuration similar to the chair shown in Figure 1 A;

[0030] Figure 2B is an unexploded front perspective view of the stack of chairs shown in Figure 2A;

[0031] Figure 2C is a rear perspective view of the stack of chairs shown in Figure 2A;

[0032] Figure 2D is a front view of the stack of chairs shown in Figure 2A;

[0033] Figure 2E is a side view of the stack of chairs shown in Figure 2A;

[0034] Figure 2F is a top view of the stack of chairs shown in Figure 2A;

[0035] Figure 2G is a bottom view of the stack of chairs shown in Figure 2A;

[0036] Figure 2H is a rear view of the stack of chairs shown in Figure 2A;

[0037] Figure 3 is a cross-sectional view along lines 3-3 of a portion of the stack of chairs shown in Figure 2E;

[0038] Figure 4 is a front perspective view of another exemplary chair;

[0039] Figure 5 is a front perspective view of still another exemplary chair; [0040] Figure 6 is a front perspective view of yet another exemplary stack of chairs, the chairs having a configuration similar to the chair shown in Figure 5;

[0041] Figure 7 A is a front perspective view of a further exemplary chair;

[0042] Figure 7B is a rear perspective view of the chair shown in Figure 7A;

[0043] Figure 7C is a front view of the chair shown in Figure 7A;

[0044] Figure 7D is a side view of the chair shown in Figure 7A;

[0045] Figure 7E is a top view of the chair shown in Figure 7A;

[0046] Figure 7F is a bottom view of the chair shown in Figure 7A; and

[0047] Figure 7G is a rear view of the chair shown in Figure 7A.

DETAILED DESCRIPTION

[0048] The present invention is directed towards a chair. The principles of the present invention, however, are not limited to chairs. It will be understood that, in light of the present disclosure, the chairs disclosed herein may have a variety of shapes, sizes, configurations, and arrangements. It will also be understood that chairs may include any suitable number and combination of features, components, aspects, and the like. In addition, while the chairs shown in the accompanying figures are illustrated as having particular styles, it will be appreciated the chairs may have any suitable style or configuration. Further, the stackable frame structure disclosed herein may be successfully used in connection with other types of objects and devices.

[0049] Additionally, to assist in the description of the chair, words such as top, bottom, front, rear, sides, right, and left are used to describe the accompanying figures which may be, but are not necessarily, drawn to scale. It will further be appreciated the chairs may be disposed in a variety of desired positions or orientations, and used in numerous locations, environments, and arrangements. A detailed description of the chair now follows.

[0050] Reference is now made to the accompanying figures, wherein like structures will be provided with like reference designations.

[0051] Figure 1A through Figure 1G illustrate a number of views of an exemplary chair 100. As shown in the figures, the chair 100 may include a seat 102 with a top portion 104 and a bottom portion 106. The chair 100 may also include a backrest 108 with a front portion 110 and a rear portion 112. In some embodiments, the backrest 108 may extend to the seat 102. Alternately or additionally, the seat 102 and backrest 108 may be formed together as a single body. The chair 100 may be configured to be stacked with one or more chairs similar to or the same as the chair 100.

[0052] A frame 114 may support the seat 102 and the backrest 108 in the desired locations. In some embodiments, the frame may include a right portion 128 and a left portion 126. The right portion 128 and the left portion 126 may both include a leg portion and a back support portion. However, other frame 114 sizes and configurations may be used. In some embodiments, the right portion 128 and the left portion 126 may be mirror configurations of the other.

[0053] In some embodiments, as best shown in Figure ID, the frame 114 may be configured such that a profile of one or more portions of the frame 114 may present a profile thickness 115 that is larger than a thickness 117 of a local portion of the frame 114. As set forth in more detail herein, the frame 114 may be configured such that the chair 100 may stack in a relatively smaller volume compared with a chair having a comparable strength and/or profile thickness. [0054] The frame 114 may include or be attached to one or more legs 116. Optionally, the frame 114 may include a right front leg 118, a right rear leg 120, a left front leg 122 and a left rear leg 124. Although the chair 100 is shown as having four legs 116, the chair 100 may include any suitable number and configuration of legs 116. In some embodiments, the right front leg 118 and the left front leg 122 may be oriented approximately seven degrees (7°) from vertical and the right rear leg 120 and the left rear leg 124 may be oriented approximately twenty-five (25°) degrees from vertical. However, other leg orientations may be used. For example, the right front leg 118 and the left front leg 122 may be orientated at different angles including larger angles such as eight degrees (8°), nine degrees (9°), ten degrees (10°), or more; or smaller angles such as six degrees (6°), five degrees (5°), four degrees (4°), or less. The right rear leg 120 and the left rear leg 124 may also be disposed at different angles including larger angles such as twenty-six degrees (26°), twenty-seven degrees (27°), twenty-eight degrees (28°), twenty-nine degrees (29°), thirty degrees (30°), or more; or smaller angles such as twenty-four degrees (24°), twenty-three degrees (23°), twenty-two degrees (22°), twenty- one degrees (21°), twenty degrees (20°), or less.

[0055] In some embodiments, the legs 116 may include feet disposed between the chair 100 and a floor or ground. The feet may alter how the chair 100 slides across the floor, decrease noise as the chair 100 is placed on or slides across the floor, decrease or eliminate damage to the floor, and the like. The right front leg 118 may include a right front foot 140, the right rear leg 120 may include a right rear foot 142, the left front leg 122 may include a left front foot 144, and the left rear leg 124 may include a left rear foot 146. In some embodiments, the right front foot 140 and the left front foot 144 may be the same, but these and other components may be formed and/or installed relative to one another in a mirrored orientation. Alternately or additionally, the right rear foot 142 and the left rear foot 146 may be the same, but these and other components may be formed and/or installed relative to one another in a mirrored orientation.

[0056] Optionally, the chair 100 may be configured to allow a single person to use the chair at one time. The chair 100, however, may be configured to allow two or more persons to sit on the chair at one time. The chair 100 may have a variety of suitable shapes, sizes, and configurations, depending, for example, upon the intended uses of the chair. For example, the chair 100 may be larger or smaller, and/or may have other suitable designs depending on intended uses of the chair, an intended appearance of the chair, an intended aesthetic of the chair, and the like.

[0057] In some embodiments, the seat 102 and/or the backrest 108 may be formed from plastic. For example, the seat 102 and/or the backrest 108 may be formed from blow-molded plastic. Forming the seat 102 and/or the backrest 108 from blow-molded plastic may allow strong, durable, and lightweight chairs 100 to be quickly and efficiently manufactured. The seat 102 and/or the backrest 108, however, may be formed from other suitable materials and/or processes. For example, the seat 102 and/or the backrest 108 may be formed from other materials such as wood, metal, composite, etc. and/or may be formed from other processes such as injection molding, extrusion molding, vacuum forming, tumble molding, and the like.

[0058] In some embodiments, the seat 102 and/or the backrest 108 may be curved, for example, to increase the comfort of the user. For example, the top portion 104 of the seat 102 may be curved to facilitate a user sitting in the chair 100. In some instances, curving the seat 102 may allow the seat to exhibit increased strength and/or rigidity compared with a seat that is generally flat or planar. Alternately or additionally, curving the seat 102 may allow the seat to meet strength and/or rigidity targets with less material compared with the seat that is generally flat or planar. Similarly, the backrest 108 may include one or more curved portions that are sized and configured to increase the comfort of the user, and/or to allow the backrest to exhibit increased strength and/or rigidity compared with a backrest that is generally flat or planar.

[0059] The chair 100 may include one or more crossbars. For example, as best seen in Figure IF, a crossbar 136 and a crossbar 138 may be used to connect the right portion 128 and the left portion 126 of the frame 114. The crossbar 136 and the crossbar 138 may be sized and configured to support the seat 102. The crossbar 136 may be located at least proximate the front portion of the seat 102 and the crossbar 138 may be located at least proximate the rear portion of the seat 102. In some embodiments, the crossbar 136 and the crossbar 138 may be at least partially located in grooves formed in the bottom portion 106 of the seat 102. In some embodiments, at least a portion of the crossbar 136 and/or the crossbar 138 may be located inside the seat 102. The crossbar 136 and the crossbar 138 may help to create a more rigid and secure chair 100. For example, the crossbar 136 and the crossbar 138 may help prevent or eliminate bending or flexing of the seat 102 and/or the frame 114 when a load or force is applied to the chair 100.

[0060] Additional crossbars may be sized and configured to support other desired portions of the chair 100. For example, one or more crossbars may also be sized and configured to support the backrest 108 and/or to connect one or more pairs of legs 116 to create a more rigid structure. Crossbars may be used to create legs 116 that are less likely to bend or flex when a load or force is applied to the chair 100.

[0061] In some embodiments the frame 114 may be structured to connect one or more pairs of legs 116 to make the chair 100 more rigid. For example, as best seen in Figure ID, the right portion 128 of the frame 114 may include a frame section 148 located and fastened to a frame section 150 below the top of the frame section 150 to make the right front leg 118 and the right rear leg 120 less likely to bend or flex when a load or force is applied to the chair 100. The left portion 126 of the frame 114 may be similarly structured if desired.

[0062] The frame 114 may be formed from a relatively strong and sturdy material such as suitable types of metal such as steel, aluminum, or the like, or any suitable combination thereof. In some embodiments, the frame 114 may be formed from hollow metal tubes that are bent or formed into the desired shapes and configurations. The frame 114, however, may be formed from other materials and/or configurations.

[0063] The chair 100 may include one or more openings 130. In particular, the backrest 108 of the chair may include an opening 130 that is sized and configured to form a handle 132. As illustrated in Figure 1A through Figure 1G, the opening 130 may extend completely through the backrest 108. Alternately, the opening 130 may extend through a portion of the backrest 108 to form the handle 132. The handle 132 may allow the chair 100 to be easily moved and may facilitate stacking and/or unstacking of the chair. Although the handle 132 is illustrated as being formed in the backrest 108, one or more handles may be alternately or additionally formed in other portions of the chair 100. Further, the handle 132 could also comprise one or more depressions, indentations and the like.

[0064] The chair 100 may be configured to stack with one or more chairs that have a configuration or arrangement similar to or the same as the chair 100. In particular, the chair 100 may be sized and configured to stack with one or more chairs that have at least a substantially similar configuration and/or arrangement as the chair. [0065] Figure 2A through Figure 2H illustrate a number of views of an exemplary stack 200 of a chair 201A, a chair 201B, a chair 201C, and a chair 201D (collectively "chairs 201"). The chairs 201 may generally correspond to the chair 100 of Figure 1A through Figure 1G. The chairs 201, however, do not have to correspond to the chairs 100 and the chairs could have any suitable size, shape, configuration and arrangement depending, for example, upon the intended use of the chairs.

[0066] Figure 2A is a partially exploded front perspective view of the stack 200 of the chairs 201. The chair 20 ID is shown above the stack of the chair 201 A, the chair 201B, and the chair 201C. The chair 201D may be placed atop the chair 201C to be included in the stack 200.

[0067] Each of the chairs 201 may include interfacing portions of a frame such as sections 202 and sections 204 as labeled on the chair 201C. The sections 202 and the sections 204 may represent portions of the chair 201C that include at least some of the surfaces that contact the chair 20 IB upon which the chair 201C is stacked. The interfacing sections 202 and the interfacing sections 204 may also include at least some of the surfaces that contact the chair 20 ID stacked upon the chair 201C.

[0068] As best shown in Figure 2E and Figure 2H, the chairs 201 may be associated with a stacking height 206. For example, each of the chairs 201 added to the stack 200 beyond a first chair, such as the chair 201 A, may increase a height 208 of the stack 200 by the stacking height 206. The stacking height 206 may directly affect the height 208 of the stack 200. In response to increasing the stacking height 206, the height 208 of the stack 200 may increase. When the stacking height 206 decreases, the height 208 of the stack 200 may decrease. Put another way, decreasing the stacking height 206 may allow more chairs to be stacked in a given height. Advantageously, decreasing the stacking height may allow more chairs to be shipped and/or stored in a given volume, potentially decreasing shipping and/or storage costs significantly.

[0069] Figure 3 is a cross-sectional view along lines 3-3 of a portion of the stack 200 of the chairs 201 shown in Figure 2E. For instance, the stack 200 of the chairs 201 may include chairs with interfacing portions. In particular, Figure 3 illustrates an interfacing portion 302A, an interfacing portion 302B, an interfacing portion 302C, and an interfacing portion 302D (collectively "interfacing portions 302"), which may generally correspond to the interfacing sections 202 and the interfacing sections 204 of Figure 2A.

[0070] Each of the interfacing portions 302 may include a receivable surface 304 and a receiving surface 306. The receivable surface 304 and the receiving surface 306 may be complementary such that the receivable surface 304 may accept, abut, at least partially contact, engage, be placed at least adjacent and/or rest on the receiving surface 306 when the corresponding chairs are stacked together.

[0071] Optionally, the receivable surface 304 and the receiving surface 306 may have substantially the same shape and may be separated by an offset 308. For example, the contour of the receivable surface 304 may follow the contour of the receiving surface 306 at the offset 308. Advantageously, this may allow a receiving surface 306 of one chair to fit closely with the receivable surface 304 of another chair when the chairs are stacked. Although shown as flat surfaces, the receivable surface 304 and the receiving surface 306 may include one or more angles, curves, bends, indentations and extrusions, and the like. For example, the receivable surface 304 and the receiving surface 306 may be curved such that a convex receivable surface and a concave receiving surface fit together when the chairs are stacked. It will be appreciated the receivable and receiving surfaces 304, 306 may have other suitable shapes, sizes, configurations and arrangements depending, for example, upon the intended use of the chairs.

[0072] In some embodiments, the contour of the receivable surface 304 may not follow the contour of the receiving surface 306, but the receivable surface 304 and the receiving surface 306 may otherwise include one or more complementary contours such that the receivable surface 304 may interface with the receiving surface 306. This may allow one or more corresponding chairs to be stacked together.

[0073] The interfacing portions 302 may also be sized and configured such that a profile 310 presented to the sides of the chair has length that is larger than the offset 308 of the receivable surface 304 and the receiving surface 306. Advantageously, a stacking height generally corresponding to the stacking height 206 of Figure 2A through Figure 2H may be associated with the offset 308. This may allow a stacking height of a chair to be advantageously decreased with little or no corresponding decrease to the strength and/or aesthetics of the chair. Alternately or additionally, the profile 310 and/or strength of a chair may advantageously be increased with little or no corresponding increase to the stacking height of the chair.

[0074] Decreasing the stacking height for a chair may be advantageous. For example, if the stacking height for a chair is decreased such that a stack of seven chairs may fit into a volume that could previously fit a stack of six chairs, roughly sixteen percent more chairs may potentially be shipped and/or stored in a given space. Similarly, if the stacking height for a chair is decreased such that a stack of seven chairs may fit into a volume that could previously fit a stack of five chairs, forty percent more chairs may potentially be shipped and/or stored in a given space. Increasing the density of chairs that may be shipped in a given volume may lower per-chair transportation costs significantly. This may be particularly important if a large number of chairs are manufactured, shipped, stored, displayed and/or transported. Thus, for example, if a large number of chairs are manufactured, shipped, stored, displayed, and/or transported, even a small decrease in stacking height may significantly reduce shipping, storing, displaying, and/or transporting costs.

[0075] In some embodiments, the profile 310 may have a length of about 0.875 in. (7/8 in.) and the offset 308 may have a length of about 0.625 in. (5/8 in.) such that the profile 310 length is about one-hundred-forty percent (140%) of the offset 308 length. Put another way, a chair with the interfacing portions 302 of Figure 3 may display the strength and/or aesthetic characteristics generally associated with a chair having a rectangular frame with a cross-sectional thickness of 0.875 in., but may have a stacking height associated with a chair having a rectangular frame with a cross-sectional thickness of 0.625 in. Advantageously, this may allow more chairs to be stacked in the same area or volume, but the chair may have the appearance of a chair with a larger frame. This may be valuable in the minds of consumers and/or retailers because the chair may be more efficiently stacked but the chair may have the strength and/or appearance of conventional chairs that do not stack as efficiently.

[0076] The interfacing portions may include other profile 310 lengths relative to the offset 308 length. For example, the profile 310 length relative to the offset 308 length may be about one-hundred-thirty percent (130%), about one-hundred-twenty percent (120%), or less. Alternately, the profile 310 length relative to the offset 308 length may be about one-hundred-fifty percent (150%), about one-hundred-sixty percent (160%), or more. [0077] The interfacing portions 302 are shown as having a parallelogram cross- section. In some embodiments, the parallelogram cross-section may be stronger than a rectangular cross-section. For instance, the parallelogram cross-section may be stronger than a rectangular cross-section oriented such that the offset 308 and the profile 310 are the same. One of skill in the art may realize, upon viewing the disclosure of this application, that other cross-section shapes may be used. For example, a frame having an off-angle rectangular cross-section, an off-angle trapezoidal cross-section, or another cross-section may be used. As further examples, a frame having an arc cross-section, an S-shaped cross-section, or other curved and/or angled cross-sections may be used in an analogous manner. The frame may also have other suitable shapes, sizes, configurations and arrangements such as rectangular, quadrilateral, rhomboid and the like.

[0078] Figure 4 is a front perspective view of another exemplary chair 400. The chair 400 may generally correspond to the chair 100 shown in Figure 1A through Figure 1G and to the chairs 201 shown in Figure 2A through Figure 2H. The chair 400 includes some elements that are similar or identical to elements of the chair 100 of Figure 1A through Figure 1G, such as the seat 102, the top portion 104 of the seat 102, the backrest 108, the front portion 110 of the backrest 108, the frame 114, the right portion 128 of the frame 114, the left portion 126 of the frame 114, the legs 116, the right front leg 118, the right front foot 140, the left front leg 122, the left front foot 144, the left rear leg 124, the left rear foot 146, the opening 130, and the handle 132, for which a more detailed description is already provided above. It will be understood the chair 400 may have any suitable shape, size, configuration and arrangement depending, for example, upon the intended use of the chair. [0079] The chair 400 may include a crossbar 402 connecting the right front leg 118 and the left front leg 122. The crossbar 402 may help create a more rigid and secure chair 400. In particular, the crossbar 402 may help prevent or eliminate bending or flexing of the chair seat 102 and/or the frame 114 when a load or force is applied to the chair 100. In some embodiments, the crossbar 402 may be located such that the crossbar is positioned above or atop the seat of another chair below the chair 400 when the chair is stacked on the other chair. The chair 400 may otherwise stack in a manner generally corresponding to the chairs described with reference to Figure 1A to Figure 3.

[0080] Figure 5 is a front perspective view of another exemplary chair 500. The chair 500 may include a seat 502 having a top portion 504 and a bottom portion (not shown) generally corresponding, respectively, to the seat 102, the top portion 104, and the bottom portion 106 of Figure 1A through Figure 1G. The chair 500 may include a backrest 506 including a front portion 508 and a rear portion (not shown) generally corresponding, respectively, to the backrest 108, the front portion 110, and the rear portion 112 of Figure 1A through Figure 1G. The chair 500 may include an opening 510 and a handle 512 generally corresponding, respectively, to the opening 130 and the handle 132 of Figure 1A through Figure 1G. It will be understood the chair 500 may have other suitable shapes, sizes, configurations and arrangements depending, for example, upon the intended use of the chair.

[0081] The chair 500 may include legs 516, including a right front leg 518, a right rear leg (not shown), a left front leg 520, and a left rear leg 522 generally corresponding, respectively, to the right front leg 118, the right rear leg 120, the left front leg 122, and the left rear leg 124 of Figure 1A through Figure 1G. The chair 500 may include a right front foot 528, a right rear foot (not shown), a left front foot 530, and a left rear foot 532 generally corresponding, respectively, to the right front foot 140, the right rear foot 142, the left front foot 144, and the left rear foot 146 of Figure 1A through Figure 1G.

[0082] The chair 500 may include a frame 514. The frame 514 may include a left backrest support 524 and a right backrest support 526. In some embodiments, the frame 514 may generally correspond to the frame 114 of Figure 1A through Figure 1G.

[0083] In this and other embodiments, the frame 514 may include another suitable configuration. By way of example, the frame 514 may be configured such that the left backrest support 524 and the left front leg 520 are formed from a side rail forming an integral, one-piece structure. The side rail may be formed from a continuous hollow metal tube bent or otherwise formed into a suitable shape. The frame 514 may also be configured such that the right backrest support 526 and the right front leg 518 are formed from another side rail forming an integral, one-piece structure. The frame 514 may also be configured such that the right rear leg and the left rear leg 522 are formed from a continuous rear leg support forming an integral, one-piece structure.

[0084] Figure 6 is a front perspective view of another exemplary stack 600 of a chair 602A, a chair 602B, a chair 602C, and a chair 602D (collectively "chairs 602"). The chairs 602 may generally correspond to the chair 500 of Figure 5. Alternatively and/or additionally, he stack 600 of the chairs 602 may generally correspond to the stack 200 of the chairs 201 of Figure 2A through Figure 2H.

[0085] Figure 7A through Figure 7G illustrate a number of views of an exemplary chair 700. As shown in the accompanying figures, the chair 700 may include a seat 702 and a backrest 704. In some embodiments, the seat 702 and the backrest 704 may be formed from a single piece of blow-molded plastic. [0086] In some embodiments, the backrest 704 may include an opening 706. The opening 706 may provide ventilation to a person using the chair 700, decrease the amount of materials used in the chair 700, reduce the weight of the chair 700, contribute to the aesthetics of the chair 700, and the like.

[0087] The chair 700 may further include a frame having a first frame piece 708 and a second frame piece 710 secured together in a suitable fashion. The first frame piece 708 may form front legs and may provide support to the backrest 704. The second frame piece 710 may form back legs and may provide support to the seat 702.

[0088] One of ordinary skill in the art may appreciate after reviewing this disclosure that the interfacing portions may be used in connection with different types and configurations of chairs. In addition, one of ordinary skill in the art may appreciate after reviewing this disclosure that the disclosed chairs may have other suitable shapes, sizes, configurations, and arrangements depending, for example, upon the intended use of the chair.

[0089] Although this invention has been described in terms of certain preferred embodiments, other embodiments apparent to those of ordinary skill in the art are also within the scope of this invention. Accordingly, the scope of the invention is intended to be defined only by the claims which follow.