FIELD OF THE INVENTION

[0001] The present invention relates to furniture and, more particularly, to office furniture for use or storage in compact spaces or work areas.

BACKGROUND OF THE INVENTION

[0002] Office furniture commonly includes work desks and chairs. Many desks and chairs have been designed and marketed for home office use, such as by a person who as converted a bedroom or similar-sized room of their home for work use. However, many people do not have a room in their home that can be dedicated to use as a home office, and even if a portion of a room can be used for work, the furniture available for such use often takes up excessive space, especially during times outside of work hours, when the office furniture does not have a purpose. With more workers doing their work from home, including apartments or other small dwellings that do not have space to easily accommodate traditional office furniture, oftentimes a choice must be made between using home furniture (such as a dining table and chair) for work, or dedicating an undesirably large amount of floor space to work furniture that becomes an inconvenient obstruction during hours outside of work.

SUMMARY OF THE INVENTION

[0003] The present invention provides a collapsible office chair and desk/storage unit with the size, functionality, and convenience of regular home office furniture, but which are configurable to a compact storage configuration to minimize the space they occupy during periods of non-use. For example, the chair's legs can provide a four-leg base with swiveling caster wheels, height adjustability, and a fixed or rotatable seat with backrest providing limited tilt for comfort, yet the chair's legs, seat, and backrest can all be pivoted or otherwise moved to occupy substantially less lateral "footprint" and vertical height for storage, such as inside a storage area of the desk/storage unit, under a table, or in a closet. The desk/storage unit has a movable work surface that can be extended to a horizontal or sloped configuration for use, and can be retracted to a vertical or upright or non-extended position for storage. The desk/storage unit may be capable of fully enclosing the chair in the stowed configuration. Additional interior storage may be provided for a computer, peripherals, or papers inside the desk/storage unit, while an upper surface may remain available for storage of a computer monitor or decorative objects to provide a more aesthetically pleasing appearance.

[0004] These and other objects, advantages, purposes and features of the present invention will become apparent upon review of the following specification in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] FIG. 1A is a perspective view of a collapsible office furniture system in accordance with the present invention, shown in a use configuration;

[0006] FIG. IB is another perspective view of the collapsible office furniture system collapsible office furniture system of FIG. 1A, shown with the collapsible chair in a stowed configuration;

[0007] FIG. 1C is another collapsible office furniture system of FIG. 1A, shown in a stowed configuration;

[0008] FIG. 2 is a perspective view of the collapsible chair in the stowed configuration in a box with exemplary stowed dimensions shown;

[0009] FIG. 3A is a perspective view of the collapsible chair in the stowed configuration, shown underneath a work table or desk;

[0010] FIG. 3B is a perspective view of two of the collapsible chairs in their stowed configuration and nested together under a work table or desk;

[0011] FIG. 3C is a perspective view of the collapsible chair with seat back in a stowed configuration and positioned underneath a table or desk;

[0012] FIG. 4 is a front elevation view of the collapsible chair in the use configuration;

[0013] FIG. 5 is a left side elevation view of the collapsible chair of FIG. 4;

[0014] FIG. 6A is another left side elevation view of the collapsible chair of FIG. 4, with seat back in the stowed configuration;

[0015] FIG. 6B is another left side elevation view of the collapsible chair of FIG. 4, with seat and seat back both in the stowed configuration, and leg assembly in the use configuration;

[0016] FIG. 7 is a front-left perspective view of the collapsible chair of FIG. 6B; [0017] FIG. 8 is another front-left perspective view of the collapsible chair of FIG. 7, shown with the leg assembly in the stowed configuration;

[0018] FIG. 9 is a left side elevation view of the collapsible chair of FIG. 8;

[0019] FIG. 10 is a top plan view of the collapsible chair of FIG. 8;

[0020] FIG. 11 A is a perspective view of a leg assembly of the collapsible chair, shown in the use configuration;

[0021] FIG. 1 IB is another perspective view of a leg assembly of the collapsible chair, shown in the stowed configuration;

[0022] FIGS. 12A-D are left side perspective views of the collapsible chair, depicting movements from the use configuration to the stowed configuration;

[0023] FIGS. 13A-D are left side perspective views of the collapsible chair, depicting movements from the stowed configuration to the use configuration;

[0024] FIG. 14 is an exploded perspective view of the collapsible chair;

[0025] FIGS. 15A-C are left side elevation views of the collapsible chair, showing internal structures and depicting movements from the use configuration to the stowed configuration;

[0026] FIGS. 16A and 16B are enlarged side elevation views of a rear portion of the seat and lower portion of the seatback of the collapsible chair, showing internal structures, and with the seat back in the use and stowed configurations, respectively;

[0027] FIGS. 17A and 17B are additional enlarged side elevation views of a rear portion of the seat and lower portion of the seatback of the collapsible chair, shown with the seat back in the use and stowed configurations, respectively;

[0028] FIGS. 18A and 18B are enlarged side elevation views of a middle region of the collapsible chair in the use and stowed configurations, respectively;

[0029] FIG. 19 is a top perspective view of a work table in accordance with the present invention, having its work surface partially opened to show internal structure and storage; [0030] FIG. 20 is a front perspective view of two work desk and storage units in accordance with the present invention, shown with cabinet doors open and an upper work surface in extended and retracted positions;

[0031] FIG. 21 is a series of left side perspective views of another collapsible chair in accordance with the present invention, depicting movements from the use configuration to the stowed configuration, and labeled with optional movement limitations;

[0032] FIG. 22 is a series of left side perspective views of the collapsible chair of FIG. 21, depicting movements from the stowed configuration to the use configuration, and labeled with optional movement limitations;

[0033] FIG. 23 is another series of left side perspective views of the collapsible chair of FIG. 21, depicting movements from the use configuration to the stowed configuration to the use configuration, and labeled with optional movement limitations;

[0034] FIG. 24 is a left side elevation of another collapsible chair in accordance with the present invention, shown in a deployed configuration;

[0035] FIG. 25 is a front-left perspective view of a seat back and base latch and release mechanism of the collapsible chair of FIG. 24;

[0036] FIG. 26 is a front-left perspective view of a rotary latch of the seat back and base latch and release mechanism of FIG. 25;

[0037] FIG. 27 is a front-right perspective view of a latch pin of the seat back and base latch and release mechanism of FIG. 25;

[0038] FIGS. 28A-28C are a series of left side elevation views of the collapsible chair of FIG. 24, with the seat and back shown moving from partially stowed to fully stowed positions;

[0039] FIG. 29 is a top plan view of the chair legs and leg mechanism of the collapsible chair of FIG. 24;

[0040] FIGS. 30A-30C are a series of front-left perspective views depicting operation of a base latch;

[0041] FIG. 31 is an enlarged front-left perspective view of the chair leg mechanism of FIG. 29; [0042] FIGS. 32A-32C are a series of top plan views of the chair legs and leg mechanism of FIG. 29, showing movement from deployed to stowed positions;

[0043] FIGS. 33A-33C are a series of front-left perspective views of the leg mechanism and locking mechanism that secures the seat back and base in stowed positions while the legs are stowed;

[0044] FIGS. 34A-34C are a series of right side elevation views of the collapsible chair of FIG. 24, showing deployment of the chair from the fully-stowed configuration to fully-deployed configuration;

[0045] FIGS. 35A-35E are a series of right side elevation views of another collapsible chair in accordance with the present invention, showing deployment of the chair from the fully-deployed configuration to fully-stowed configuration, and with details omitted;

[0046] FIG. 36A is a rear-right perspective view of the collapsible chair of FIG. 35A, showing details omitted from FIGS. 35A-35E;

[0047] FIG. 36B is another rear-right perspective view of the collapsible chair of FIG. 35A, shown with the seat pan released and partially moved to the stowed configuration, and with an enlarged inset view of a central region of the chair;

[0048] FIGS. 36C and 36D are additional rear-right perspective views of the collapsible chair of FIG. 35 A, shown in final stages of seat movement to the fully-stowed configuration, with legs remaining in the deployed position;

[0049] FIGS. 37A-37C are a series of front perspective views of the collapsible chair of FIG. 35 A, showing movement of the seat pan and seatback from fully-stowed configuration to fully- deployed configuration;

[0050] FIG. 38 is an enlarged front perspective view of the seat pan and mechanism portions of the collapsible chair of FIG. 35, shown just prior to reaching the fully-stowed configuration;

[0051] FIG. 39 is top plan view of the base of the collapsible chair of FIG. 35A, with the legs shown in the fully deployed configuration and a lockout plunger disengaged from the leg-release mechanism; [0052] FIG. 40A is a top plan view of the central hub portion area designated XL in FIG. 39, showing the leg-release mechanism with cover removed;

[0053] FIG. 40B is a top plan view of the central hub portion and leg-release mechanism of FIG. 40A, with a lockout plate of the leg-release mechanism omitted to show underlying structure;

[0054] FIG. 40C is another top plan view of the central hub portion and leg-release mechanism of FIG. 40 A, shown with the lockout plunger initially engaging the leg- release mechanism;

[0055] FIG. 40D is another top plan view of the central hub portion and leg-release mechanism of FIG. 40 A, shown with the lockout plunger fully engaging the leg-release mechanism;

[0056] FIG. 40E is another top plan view of the central hub portion and leg-release mechanism of FIG. 40 A, shown with the front legs moving partially toward their stowed configuration;

[0057] FIG. 40F is another top plan view of the central hub portion and leg-release mechanism of FIG. 40 A, shown with the front legs fully in the stowed configuration and the leg-release mechanism leaving the lockout plunger secured in the leg-release mechanism;

[0058] FIG. 41 is a front elevation view of another seat pan support and latching mechanism, shown in the fully deployed configuration;

[0059] FIGS. 42A and 42B are front partial-sectional elevation views of the seat pan support and latching mechanism of FIG. 41, shown with the seat pan support in respective positions when unweighted and weighted by a user;

[0060] FIG. 43A is a side elevation view of the backrest assembly of the collapsible chair of FIG. 35 A, shown in a middle-height position;

[0061] FIG. 43B is a side partial-sectional elevation view of the backrest assembly of FIG. 43 A, showing the adjustment mechanism;

[0062] FIG. 44 is a top plan view of the backrest assembly of FIG. 43 A, showing the adjustment mechanism;

[0063] FIGS. 45A and 45B are additional side elevation views of the backrest assembly of FIG. 43 A, shown in the lowered and raised positions;

[0064] FIG. 46A is a front perspective view of a storage and desk unit in accordance with the present invention, shown with front doors open and top work surface retracted; and [0065] FIG. 46B is another front perspective view of the storage and desk unit of FIG. 46A, shown with the top surface extended.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0066] Referring now to the drawings and the illustrative embodiments depicted therein, a collapsible office furniture system 100 includes a collapsible chair 110 and a collapsible desk unit 120, both of which can be configured between respective deployed or "use" configurations and stowed configurations, such as shown in FIGS. 1A-1C. Referring to FIG. 1 A, collapsible chair 110 includes a seat 112, a seat back 114, a seat post 116, and a leg assembly 118, while collapsible desk unit 120 has a cabinet-like form including a top portion or panel 122, a pair of spaced-apart upright supports or legs 124 extending downwardly from the top portion 122, a rear panel or support 126, a pair of doors 128 opposite the rear panel 126, and a movable work surface 130. The desk unit's main components cooperate to define a chair storage area 132 that is sized and shaped to receive the chair 110 when it its stowed configuration, such as shown in FIG. IB. Desk unit 120 may be free-standing, or may be secured to a wall or ground surface to prevent movement.

[0067] The ability to reconfigure the collapsible chair 110 allows it to assume a very compact stowage or "non-use" configuration with a significantly reduced footprint (occupied floor area) for times when the chair is not in use, making the collapsible office furniture system 100 particularly well-suited for small work spaces that are also used as dwelling spaces, such as in apartments, dormitories, or other dwellings where space is limited. Thus, dwelling spaces that would not normally be considered sufficient in size to have a dedicated work area may nonetheless be provided with a temporary dedicated work area that can be stowed or reconfigured to a compact size when not in use. The chair 110 may be used and stored independently of desk unit 120, such as underneath a narrow work desk or table 134a (FIG. 3 A) or underneath a wider work desk or table 134b (FIGS. 3B and 3C). When chair 110 is in its stowed configuration, it may be nested with other chairs 110 of the same design, such as shown in FIG. 3B. Alternative tables or desk units are shown in FIGS. 19 and 20.

[0068] As best seen with reference to FIGS. 4, 5, and 14, the collapsible chair's seat 112 includes a seat pan 136 coupled to a seat bracket 138 along a bottom surface thereof, optionally with a set of resilient bumpers 140 disposed between the seat pan 136 and bracket 138 to permit limited tilting movement of seat pan 136 relative to seat bracket 138 when the seat 112 is in the use configuration. A forward Z-bracket 142a and rearward mounting plate 142b are provided for securing seat pan 136 to seat bracket 138 with a rearward tilt to the seat pan 136 as shown in FIG. 5.

[0069] The collapsible chair's seatback 114 includes a backrest 144 and a backrest bracket 146 for coupling backrest 144 to seat bracket 138. Referring to FIGS. 5 and 14, backrest 144 is secured to bracket 146 with a backrest mounting plate 148, a thumbscrew 150, and another pair of resilient bumpers 140 that allow limited pivoting movement of backrest 144 relative to backrest bracket 146 and mounting plate 148, for comfort. Backrest bracket 146 is generally J- shaped and includes a longitudinal slot 152 through which a shaft of thumbscrew 150 passes to provide height adjustment for the backrest 144 relative to the bracket 146. At its lower end region, backrest bracket 146 defines a tubular pivot-pin receiver 154 and a laterally-extending pivot tongue 156. As will be described in more detail below, tubular pivot pin receiver 154 and a corresponding bracket pivot pin receiver 158 at a rear portion of seat bracket 138 are designed to align coaxially with one another and receive a backrest pivot pin 160. Similarly, pivot tongue 156 defines a pair of release pin receiver openings 162 that align coaxially with a corresponding bracket release pin receiver 164 that is forward of the bracket pivot pin receiver 158, to receive a backrest release pin 166, which can also be used to secure backrest bracket 146 in its stowed position as shown in FIGS. 16B and 17B. Pivot tongue 156 may engage a compressible and resilient pad 167, which is positioned between an upper surface of pivot tongue 156 and an upper surface of seat bracket 138 (FIG. 17A) to permit limited rearward pivoting movement of backrest bracket 146 and backrest 144, for comfort.

[0070] Seat post 116 may be a conventional component that optionally provides height adjustability for seat 112 relative to leg assembly 118. In the illustrated embodiment, and as best shown in FIG. 14, seat post 116 is a gas-charged unit having an upper portion 116a with an inner piston 168 and release button 170, and an upper seat post bracket 172 that supports a release lever 174 for selectively actuating the release button 170 and allowing the inner piston 168 to be raised or lowered relative to a lower portion 116b that includes a cylinder 176 that receives piston 168. [0071] Upper seat post bracket 172 is coupled to seat bracket 138 via an intermediate bracket 178. Intermediate bracket 178 includes seat pivot pin holes 180 that align with corresponding pivot pin holes 182 at a lower region of seat bracket 138 so that both sets of holes 180, 182 receive a seat pivot pin 184. Intermediate bracket 178 further includes seat release pin lower holes 186a that align with corresponding release pin holes 188 at the lower region of seat bracket 138 so that both sets of holes 186, 188 receive a seat release pin 190 when seat 112 is in the use configuration of FIGS. 4-6A, 12A, 12B, 13C, 13D, and 18A. Finally, intermediate bracket 178 defines seat release pin upper holes 186b that receive the seat release pin 190 only when seat 112 is in the stowed configuration of FIGS. 6B, 7-9, 12C-13B, and 18B.

[0072] In the illustrated embodiment, leg assembly 118 includes a structural center tube 192 that receives the seat post lower portion 116b and supports four legs that extend radially outwardly from an upper region thereof, such as shown in FIGS. 4-9 and 11 A- 14. The legs include two fixed legs 194 that are rigidly coupled to center tube 192, and a pair of pivotable legs 196a, 196b that are movable between a use configuration (FIGS. 1A, 3C, 4-7, 11A, 12A-12C, 13B-D, and 14) and a stowed configuration (FIGS. 1B-3B, 8-10, 11B, 12D, and 13A). A pair of partial-disc- shaped brackets 198 extend radially outwardly from a first or front side of center tube 192, and are received in corresponding slots 200 formed at inboard or proximal ends of the pivotable legs 196a, 196b, such as shown in FIGS. 5-6B, 8, 9, 1 IB, and 12A-14. Pivotable legs 196a, 196b are coupled to disc brackets 198 by respective leg pivot pins 201 (FIGS. 11 A and 1 IB). Optionally, disc brackets 198 may define circumferential slots, grooves, or ridges (not shown) that are engaged by corresponding shapes (not shown) at the pivotable legs' slots 200, so that the pivotable legs 196a, 196b can be pivoted circumferentially around center tube 192 while remaining secured thereto.

[0073] A releasable lock mechanism is provided to secure pivotable legs 196a, 196b in their deployed or use configuration. For example, as shown in FIGS. 4, 5, and 7-9, a spring-loaded release pedal 202 may be coupled to center tube at its front or first side and covering central regions of the disc portions 198. Release pedal 202 includes a ramped latch-hook 204 at each side, for engaging a lower portion of each pivotable leg 196a, 196b and securing the pivotable legs in their use configuration, such as shown in FIGS. 4, 7, and 11 A. Release pedal 202 may be pushed downwardly to overcome spring force and disengage latch hooks 204 from the pivotable legs 196a, 196, thereby allowing the pivotable legs to be moved out of their use configuration and into their stowed configuration, such as shown in FIGS. 8-10 and 1 IB. The pivotable legs 196a, 196b may be returned to their use configuration by manually pivoting them away from the stowed configuration until each pivotable leg fully engages its corresponding latch hook 204, which lowers during initial engagement and snaps up to secure the leg once the latch hook is fully engaged.

[0074] The pivotable legs 196a, 196b are selectively repositionable between a use configuration in which they are spaced a first distance away from corresponding fixed legs 194, and a stowed configuration in which the pivotable legs are moved closer to the corresponding fixed legs 194. In the stowed configuration, the pivotable legs 196a, 196b extend outwardly away from one another. The center of gravity of the chair, particularly with the seat 112 and seat back 114 stowed, is between the stowed pivotable legs 196a, 196b and the fixed legs 194 so that the chair remains stable and can be moved around by a user without tipping, even when the pivotable legs 196a, 196b are stowed. Optionally, seat bracket 138 and the other components coupled thereto (including seat 112, seatback 114, and seat post bracket 172) are not rotatable or pivotable about a vertical axis extending through seat post 116, such that seat 112 is only pivotable to the stowed configuration in the direction toward fixed legs 194, which ensures that the chair's center of gravity moves aft toward fixed legs 194 when the seat 112 is stowed.

[0075] While FIGS. 12A-12D depict basic chair movements from the use configuration of FIG. 12A to the stowed configuration of FIG. 12D, and FIGS. 13A-D depict the basic chair movements from the stowed configuration (FIG. 13 A) back to the use configuration (FIG. 13D), it is envisioned that various release and lockout mechanisms may be provided for safety, and to ensure that the chair's stowage mechanisms are only operated in a desired order, with one stowage step completed before the next stowage step may be initiated, for example. FIGS. 21 and 22 provide additional details on such release and lockout mechanisms. For example, in reference to the first drawing of FIG. 21, the seat 112 and legs 118 are not movable to their stowed positions while the seatback 114 is in the use configuration, and the first stowage step must therefore be to move the seatback 114 forward to a first detent position (arrow 1 in the second drawing of FIG. 21), at which point the chair 110 may be stored under a conventional desk or table, for example. Before the seat 112 can be pivoted rearwardly from the use configuration to the stowed configuration in the third drawing of FIG. 21, the seatback 114 must first be moved further forward and down to a second detent position (arrow 2 in the second drawing of FIG. 21), which releases the seat 112 to pivot to the stowed configuration in the third and fourth drawings of FIG. 21. The act of tilting the seat 112 and seatback 114 fully rearwardly, as depicted in the third drawing of FIG. 21, releases the pivotable legs from a locked use configuration, and allows them to be pivoted to the stowed configuration of the fourth drawing of FIG. 21, in which the chair's seatback 114, seat 112, and legs 118 have all assumed their fully stowed configurations. Optionally, springs, latches, push-to-release mechanisms, and dampening devices may be used to facilitate movement between use and stowed configurations.

[0076] Similarly, and with reference to FIG. 22, the seat 112 and seatback 114 may be latched or retained in their stowed configurations until the pivotable legs have been moved and secured in their use configuration (first and second drawings of FIG. 22). The seatback 114 may be retained in its stowed configuration until the seat 112 has been fully moved to its use configuration, such as depicted in the second and third drawings of FIG. 22. Once the seat is fully in its use configuration, as depicted in the fourth drawing of FIG. 22, its height may be adjusted using release lever 174 to adjust seat post 116, the pivotable legs are locked against moving out of the use configuration, and the seat 112 cannot pivot out of the use configuration. Similar stowage (fold) and out-of-storage (unfold) steps are illustrated and described in FIG. 23. Thus, one chair movement action may enable the next, or one chair movement may inhibit another chair movement, in order to ensure safe and stable use and stowage of the chair.

[0077] Referring now to FIGS. 24-34C, another collapsible chair 400 having a seat 412 and seatback 414 supported on a seat post 416, and a leg assembly 418 that supports the seat post 416. Leg assembly 418 includes a leg stowage and deployment mechanism that allows a front pair of legs 420 to pivot simultaneously between an extended or deployed configuration (FIGS. 24, 28A-29, 32A, and 34C) and a retracted or stowed configuration (FIGS. 32C and 34A). When the front legs 420 are stowed, the leg stowage and deployment mechanism captures a pin on a seat back bracket (FIGS. 33A-33C and 34A-34C) to retain the seat 412 and seatback 414 in the stowed configuration of FIG. 34A. FIG. 28C depicts the seat 412 and seatback 414 in the fully stowed configuration, prior to moving the front legs 420 to their stowed position that will capture the pin as shown in FIGS. 33A-33C, and as shown in FIGS. 34A-34C when viewed in reverse order. This prevents a user from deploying the seat 412 and/or seatback 414 when the legs 420 are not deployed, so that the chair 400 cannot be used when the legs 420 are in the less stable stowed configuration. [0078] To reconfigure the chair 400 from its deployed or use configuration to its stowed or nonuse configuration, a user first releases two latches as shown in FIGS. 25-27. In the illustrated embodiment, a rotary latch may be cable-actuated (FIGS. 25 and 26) and a spring-loaded plunger pin may be actuated by a release handle (FIGS. 25 and 27). Both latches are released simultaneously by a user in order to initiate the movement of the seat 412 and seatback 414 from the deployed configuration to their stowed configuration as shown generally in FIGS. 28A-28C. By requiring that two separately-actuated latches be released simultaneously in order to reconfigure the seat 412 and seatback 414, the risk of a user unintentionally releasing the seat 412 and seatback 414 is reduced, as releasing either one of the rotary latch or the plunger will have no effect until the other is also released.

[0079] As the seat 412 tilts back toward its stowed configuration, a base latch is urged from its latched position (FIG. 30A) toward its unlatched position (FIG. 30). The base latch secures a slidable base plate that can slide relative to seat post 416 (FIG. 31). The base plate has two sets of teeth opposite the base latch, the sets of teeth serving as gear racks for pinion gears that rotate with the respective front legs 420. By tilting seat 412 to its stowed configuration and causing the base latch to release the base plate (FIG. 30C), which makes it possible for the front legs 420 to be moved to their stowed configuration (FIGS. 32A-32C), while the base plate maintains the base latch in the released position such that the base latch will not prevent the base plate and legs 420 from moving back to the deployed position. A pin associated with the seat back bracket lowers into horizontal alignment with a pair of metal ears that extend up from the base plate when the seat back bracket reaches its fully stowed configuration (compare FIG. 34B to FIG. 34C, and observe pin lowering in FIGS. 30A-30C). When the front legs 420 are moved to their stowed position of FIGS. 32C and 34A, the metal ears move rearwardly to capture the pin (see FIG. 33, compare FIG. 33B to FIG. 33A, and compare FIG. 34A to 34B).

[0080] Referring now to FIGS. 35A-45B, another collapsible chair 600 includes a seat 612 and seatback 614 supported on a seat post 616, and a leg assembly 618 that supports the seat post 616. As will be described in more detail below, collapsible chair 600 requires that a user take affirmative steps, in a specified order, to move the chair from the fully deployed configuration of FIGS. 35 A, 36A, and 37C, to the fully stowed configuration of FIGS. 35E, 36D, and 37A. The chair's mechanisms prevent a user from sitting in seat 612 while leg assembly 618 is retracted, and prevent leg assembly 618 from retracting while the seat 612 is deployed or in-transit from deployed to stowed. Once chair 600 is in the fully stowed configuration, leg assembly 618 must be deployed before seat 612 and seatback 614 can be moved to their deployed position. As a result, chair 600 cannot be used until it is fully in the deployed configuration.

[0081] Much like chair 400 that is described above with reference to FIGS. 28A-28C, collapsible chair 600 utilizes a four- bar linkage 619 to guide the movement of seat 612 and seatback 614 between the deployed and stowed configurations as shown in FIGS. 35A-35E. Referring to FIGS. 35D and 37A, four-bar linkage 619 includes a lower link 619a coupled between a forward-upper portion of a seat support piece or bracket 658 (mounted at an upper portion of the seat post 616) and a rear link 619b, the rear link 619b coupled between lower link 619a and a rear portion of a seat frame piece or seat bracket 656, a portion of the seat frame 656 extending between rear link 619b and an rearward-upper portion of the seat support bracket 658, and the upper portion of the seat support bracket 658 between the coupling points of the seat frame 656 and the lower link 619a. As seat 612 tilts backwards, seatback 614 tilts forward relative to seat 612 until a backrest 644 of seatback 614 lies in close proximity to a seat pan 636 of seat 612, such as shown in FIGS. 35C-35E. With seat 612 and seatback 614 in this configuration, they are not usable for sitting. Only after seat 612 and seatback 614 have reached their fully stowed configuration of FIG. 35C, can a pivotable front pair of legs 620 be moved out of their deployed configuration of FIG. 35C and toward their fully stowed configuration of FIG. 35E. FIG. 35D depicts an in-transit position of legs 620.

[0082] A leg-release mechanism 622 (FIGS. 45A-45F) is actuated by a lockout plunger 624 located along a lower region of backrest bracket 646 as shown in FIGS. 36A-36C. During movement of seat 612 and seatback 614 to the stowed position, plunger 624 moves down and forward relative to seat post 616 and leg-release mechanism 622 at a central hub portion 618a of leg assembly 618, as shown progressively in FIGS. 36A-36C, until plunger 624 is received into an opening 625 along the upper-rear portion of the central hub portion 618a of leg assembly 618. In FIG. 36D the plunger 624 is fully received in opening 625 and mechanism 622. It should be appreciated that plunger 624 is not illustrated in FIGS. 35A-35E, but if the plunger 624 were present in those views it would be fully received in the opening and the leg-release mechanism in the positions depicted in FIGS. 35D and 35E. [0083] Leg-release mechanism 622 is normally obscured from view by a cover 623 (FIG. 39), and is shown with the cover removed in FIGS. 40A-40F. When seat 612 and seatback 614 are fully deployed, plunger 624 is spaced above and behind leg-release mechanism 622, such as shown in FIGS. 40A and 40B. Each movable leg 620 has a pivotable mount 626 at its proximal end, with a radially- extending lobe 628 extending in the direction opposite the respective leg 620, as best shown in FIG. 40B. Each lobe 628 supports a respective vertical pin 630 that is received in a respective forward slot 632 of a synchronizing and locking plate 634 (plate 634 not shown in FIG. 40B). Synchronizing plate 634 defines a large central opening 636 having a curved forward edge 636a that conforms to the round outer surface of seat post 616, parallel side edges 636b that are spaced apart by approximately the diameter of seat post 616, a flat rear edge 636c, and a rear opening or slot 636d for receiving plunger 624.

[0084] A pair of ramped retainers 638 are spring-biased inwardly, to the position shown in FIGS. 40A and 40B, to secure synchronizing and locking plate 634 in its rearward-most position of FIG. 40A. A pair of downwardly-extending pins 640, at a rear portion of plate 634, engage rear surfaces 638a of ramped retainers 638 when legs 620 are in their fully extended positions and plunger 624 has not been inserted into opening 625 of the central hub portion 618a of leg assembly 618 or the slot 636d formed in plate 634. With ramped retainers 638 at their inward positions of FIGS. 40A and 40B, the synchronizing and locking plate 634 is prevented from moving forwardly due to pins 640, which in turn secures movable legs 620 in their extended positions because the pins 630 at each lobe 628 of pivotable mount 626 are trapped in forward slots 632 of plate 634. Therefore, movable legs 620 cannot be moved to their retracted or stowed positions while seat 612 and seatback 614 (and therefore plunger 624) are in their deployed configuration or in an in-transit position.

[0085] Referring to FIG. 40C, a forwarded tip of plunger 624 is inserted into opening 625 of the central hub portion 618a of leg assembly 618, and also into slot 636d of plate 634, as seat 612 and seatback 614 approach their fully-stowed configuration. Plunger 624 includes a pair of outwardly-biased ramped latch tabs 642, which are forced inwardly by surfaces that define upright sides of opening 625 in the central hub portion 618a of leg assembly 618, as plunger 624 is inserted as shown in FIG. 40C. In the plunger's position of FIG. 40C, forward corners of plunger 624 make initial contact with respective ramped surfaces 638b of ramped retainers 638. Further forward movement of plunger 624 causes ramped latch tabs 642 fully retract as they slide into slot 636d of plate 634, and begins to force ramped retainers 638 outwardly so that they are no longer engaged by pins 640 of plate 634. At the position depicted in FIG. 40D, seat 612 and seatback 614 are almost fully stowed, with only a small amount of further travel remaining to urge plunger 624 into full engagement with leg-release mechanism 622, as shown in FIGS. 40E and 40F.

[0086] Referring again to FIG. 40D, with ramped retainers 638 retracted outwardly by the leading corners of plunger 624, the synchronizing and locking plate 634 is free to move forwardly in response to pivoting movement of legs 620 away from their fully-deployed positions. This movement of legs 620 is substantially synchronized by plate 634, which is prevented from pivoting around seat post 616 by the presence of plunger 624 in slot 636d, and optionally by respective guide surfaces 648 of the central hub portion 618a of leg assembly 618, which are located along respective sides of plate 634. Therefore, only after a user has first moved seat 612 and seatback 614 to the fully stowed position is the plunger 624 fully inserted into legrelease mechanism 622 so that movable legs 620 can be manually retracted, thus drawing plate 634 forward by engagement of pins 630 with the plate's slots 632. Until plate 634 is free to move forward because ramped retainers 638 have been forced outwardly (by plunger 624) to disengage pins 640, the movable legs 620 remain locked in their deployed positions.

[0087] In FIGS. 40E and 40F, plunger 624 is shown fully inserted into leg-release mechanism 622, such that the plunger's ramped latch tabs 642 are spring-biased outwardly in front of the surfaces that define opening 625 along the upper- rear portion of the central hub portion 618a of leg assembly 618. Ramped latch tabs 642 thus secure plunger 624 in the fully inserted position, thereby securing seat 612 and seatback 614 in their fully-stowed configuration until latch tabs 642 are retracted by a subsequent leg-extension step, described below. In FIGS. 40D-40F the plunger 624 is no longer actuating any part of leg-release mechanism 622. Instead, the movements of mechanism 622 from FIG. 40D to FIG. 40E, and from FIG. 40E to FIG. 40F, are caused by manual movement of legs 620 from their fully deployed positions of FIG. 40D to their fully stowed positions of FIG. 40F. Comparing FIG. 40E to FIG. 40D, it can be seen that movable legs 620 have been pivoted part- way from deployed to stowed, causing pins 630 to traverse approximately halfway through their respective slots 632 in plate 634, and drawing plate 634 forwardly so that the rearward portions of plate 634 defining slot 636d allow the plunger's spring-biased ramped latch tabs 642 to begin to extend outwardly to secure plunger 624 as described above. This forward motion of plate 634 also causes pins 640 engage the ramped inner surfaces 638b of ramped retainers 638.

[0088] Final forward motion of plate 634, caused by final stowage movement of the legs 620, causes a forward edge of plate 634 to contact a forward surface 635 of the central hub portion 618a of leg assembly 618 as shown in FIG. 40F, which prevents further rearward-to pivoting movement of legs 620 so that the legs 620 remain forward of the chair's center of gravity. This final forward movement of plate 634 also forces ramped retainers 638 to their maximum outboard positions (FIG. 40F), and allows the plunger's ramped latch tabs 642 to extend fully outwardly. In this position with legs 620 retracted, leg-release mechanism 622 does not allow plunger 624 to be withdrawn from opening 625 or slot 636d, and therefore does not allow seat 612 and seatback 614 to be moved away from their stowed configuration. In order to move seat 612 and seatback 614 away from their stowed configuration, plunger 624 must be freed to move out of opening 625 and slot 636d, which can only be accomplished by retracting the plunger's ramped latch tabs 642. To do this, legs 620 must be manually moved to their deployed positions of FIG. 40D, which forces plate 634 rearwardly by engagement of pins 630 in slots 632. As plate 634 slides rearwardly, its rear portion defining slot 636d slides along the ramped outboard surfaces of ramped latch tabs 642 retract them inwardly (FIG. 40E compared to FIG. 40F) until they are fully retracted (FIG. 40D) and can pass rearwardly through opening 625 once legs 620 are fully extended and a user begins to move seat 612 and seatback 614 away from their stowed configuration.

[0089] The movement of seat 612 and seatback 614 from stowed configuration to deployed configuration are depicted in FIGS. 37A-37C, which show a spring-biased thumbscrew 650 that is used to secure seat 612 in the deployed configuration. Thumbscrew 650 has a knurled gripping portion 652 that is accessible to a user by reaching under seat pan 636, and a threaded tip portion 654. Thumbscrew 650 passes through the seat frame piece or seat bracket 656, where a spring (not shown) urges thumbscrew 650 in an inboard direction when the spring force is not overcome by an outward-pulling force applied by a user to gripping portion 652. Referring to FIG. 38, the spring force causes tip portion 654 to engage and slide along a ramped surface 658a of the seat support piece or bracket 658 (to which four-bar linkage 619 is attached) as seat 612 is pivoted toward the fully-deployed configuration of FIG. 37C. A bore 660 is formed in an outboard surface of support piece 658, and receives tip portion 654 as seat 612 reaches its fully deployed configuration. The spring force of thumbscrew 650 forces tip portion 654 into bore 660 so that seat 612 is retained in the deployed configuration once reached. Desirably, the user will then grasp gripping portion 652 and rotate thumbscrew 650 until a male threaded portion of tip portion 654 is threadedly engaged with a corresponding female threaded portion of bore 660, so that's tip portion 654 cannot be inadvertently pulled out of engagement with bore 662 release seat 612. With seat 612 and seatback 614 secured in their deployed configuration of FIG. 37C, legs 620 are prevented from retracting by leg-release mechanism 622, described above. In fact, during most of the transition travel of seat 612 and seatback 614, legs 620 are secured against movement away from their deployed positions by plate 634, which is held in its rearward-most position by ramped retainers 638 as described above. This prevents seat 612 from being used for seating at substantially all times that legs 620 are not fully deployed.

[0090] Thumbscrew 650 provides a two-step device for securing seat 612 in the deployed configuration, so that a single inadvertent movement of thumbscrew 650 cannot release seat 612 for movement to the stowed configuration. A user must first rotate thumbscrew 650 to disengage the threads from bore 660, and then pull thumbscrew 650 outwardly to disengage tip portion 654 from bore 660, which allows seat 612 and seatback 614 to be pivoted toward their stowed configuration along travel motions dictated by four-bar linkage 619.

[0091] It will be appreciated that other two-step devices for securing seat 612 may be envisioned, such as shown in FIGS. 41-42B. In those drawings, a partially-toothed plunger tip 662 is received in a partially-toothed bore 660' of a seat support piece 658' that has a ramped surface 658a', which correspond to like-numbered components discussed above. Plunger tip 662 is received in a tubular support 664 that contains a coil spring 666 for biasing plunger tip 662 into bore 660'. Plunger tip 662 is coupled to an L-shaped handle 668 having a horizontal shaft portion 668a that passes through spring 666 and tubular support 664, and an angled gripping portion 668b that extends outwardly from tubular support 664. Preferably, the engagement of plunger tip 662 and horizontal shaft portion 668a with tubular support 664 exhibits sufficiently low friction such that the weight of angled gripping portion 668b is sufficient to cause gripping portion 668b to rotate downwardly as shown in FIGS. 41-42B when not being grasped and manipulated by a user. [0092] The teeth along the partially-toothed plunger tip 662 are arranged along the same side as the direction of angled gripping portion 668b, so that the teeth face downwardly when gripping portion 668b is angled downwardly as shown in FIGS. 42A and 42B. The teeth of partially- toothed bore 660' are arranged along a lower surface thereof (FIGS. 42 A and 42B) so that they can only be engaged by the teeth of plunger tip 662 when angled gripping portion 668b is angled downwardly as shown. In this way, plunger tip 662 and handle 668 operate in much the same way as thumbscrew 650, to the extent that handle 668 must be initially rotated to disengage teeth of plunger tip 662 from the teeth of bore 660', before the handle 668 can be pulled outwardly to disengage plunger tip 662 from bore 660' and allowing seat 612 two pivoted away from the deployed configuration.

[0093] Optionally, and as shown in FIGS. 42A and 42B, seat 612 may be biased slightly upwardly relative to seat support piece 658' so that plunger tip 662 is urged into engagement with and upper surface of bore 660' when a user is not seated. This causes the teeth of plunger tip 662 to disengage the teeth of bore 660' when the chair 600 is not in use, and allows a user to pull outwardly on the handle 668, and thereby disengage plunger tip 662 from bore 660' even without rotating gripping portion 668b away from the downward-angled orientation. Thus, when no user is seated, as would be the case in FIG. 42A, a single outward-pulling a motion on handle 668 is all that is needed to release seat 612 and seatback 614 from their deployed configuration. When a user is seated and weighing upon seat 612, this overcomes the upward-biasing force of the seat- to-support-peace coupling and causes seat 612 to move slightly downwardly relative to seat support piece 658' so that the teeth of plunger tip 662 engage the teeth of bore 660'. This engagement prevents a seated user from releasing plunger tip 662 to initiate the stowage motion, unless they deliberately rotate handle 668 first. However, because bore 660' only has teeth along its lower surface, handle 668 may be prevented from rotating when the circumferential ends of the plunger tip teeth contact the circumferential ends of the bore teeth, which will occur only if sufficient weight is placed on seat 612.

[0094] Optionally, the teeth of plunger tip 662 in the teeth of bore 660' are sized and shaped such that, even when no weight is placed on seat 612 (FIG. 42 A), handle 668 may not be withdrawn horizontally to disengage plunger tip 662 from bore 660' until handle 668 is sufficiently rotated (such as by about 90°) to fully disengage the teeth from one another. In that manner, a user is entirely prevented from releasing handle 668 while seated, and may only release handle 668 when not seated, by first rotating the handle to fully disengage the teeth and then pulling it outwardly to fully disengage the plunger 662 from the bore 660'. The seat release mechanism of FIGS. 41-42B is therefore easy to use, returns itself to a fully secured position by a combination of spring force and gravitational force, is not operable while a user is seated, and requires a simple but two-step motion (only possible when the seat is unloaded) to initiate the stowage sequence.

[0095] Collapsible chair 600 may be stored inside a storage and desk unit 720 having a pair of front doors 728 that, once pivoted open as shown in FIG. 42A, can be retracted rearwardly into a chair storage area 732 along interior surfaces of respective spaced-apart upright supports or sidewalls 724. Doors 728 can pivot to a fully closed position when chair 600 is located in storage area 732, presenting the appearance of a conventional storage cabinet. A top panel 722 extends between top edges of sidewalls 724, and is extendable in a forward direction as shown in FIG. 46B to provide a convenient work surface for a person seated at a chair. An internal storage tray 730 is located at an upper-rear region of storage area 732, and is revealed when top panel 722 is moved to its forward position. Storage tray 730 may include one or more pass-throughs for electrical cords, electrical power and/or data outlets, divided storage areas, and the like, which are closed off and not visible when top panel 722 is moved to its closed or rearward position of FIG. 46A. A recessed area 722a along a rear edge portion of top panel 722 provides a gripping surface for pulling top panel 722 to its forward position, and also provides a cord pass-through for any electrical or electronic devices or lighting that may be positioned atop top panel 722.

[0096] Referring to FIGS. 43A-45B, seatback 614 provides height adjustability for backrest 644 relative to backrest bracket 646 using a friction mechanism 670 operated using a hand-operated nut 672. Hand-operated nut 672 is threadedly engaged with a threaded shaft portion 674a of a T- bolt 674, which has an enlarged head portion 674b movably coupled to backrest 644 at a vertical C-shaped channel 675, as best shown in FIG. 44. A smooth shaft portion 674c is located between threaded shaft portion 674a and enlarged head portion 674b, and is received through an opening 676 formed in backrest bracket 646 when hand-operated nut 672 is sufficiently loosened. When hand-operated nut 672 is sufficiently loose, enlarged head portion 674b may traverse through C- shaped channel 675 and allow backrest 644 to move between a fully lowered position (FIG. 45 A) and a fully raised position (FIG. 45B), and along a continuum of intermediate positions including the middle position of FIGS. 43 A and 43B.

[0097] Therefore, the collapsible furniture of the present invention provides sturdy furniture suitable for daily use, which is collapsible to a substantially smaller configuration for storage, and which is readily convertible from a deployed or in-use configuration to a stowed or non-use configuration. Despite being readily convertible, mechanisms may be used to help ensure that a user does not inadvertently put the furniture into an unsafe condition, such as collapsed chair legs while the seat is still positioned for use. In some cases, two-step actuation may be required to initiate a change from the deployed configuration to the stowed configuration, while mechanisms help ensure a desired order of steps.

[0098] Changes and modifications in the specifically described embodiments may be carried out without departing from the principles of the present invention, which is intended to be limited only by the scope of the appended claims, as interpreted according to the principles of patent law including the doctrine of equivalents.