RELATED APPLICATION DATA The present application claims priority to U.S. Provisional Application No. 61/860,282 filed in the United States Patent Office on Jul. 31, 2013, the entirety of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention is directed toward ready-to-assemble modular furnishings composed of interlocking planar materials. In particular, the present invention relates to furniture fit together from reconfigurable interlocking panels using corresponding slot and tab elements to assemble or disassemble such components without need for tools or fasteners. The modular furniture system also includes the complementary arrangement of exterior and interior panels to hide the joinery formed by the slot and tab elements, and further utilizes selectively movable and/or detachable panels to conceal the contents of storage compartments.
2. Description of the Prior Art
The Internet has created exceptional growth in business-to-consumer e-commerce sales over the last decade. The distribution of products and services once only available at local “brick and mortar” establishments has rapidly transitioned to virtual on-line shopping portals that are now accessible to a global audience. To be sure, the underlying activity of e-commerce has not only changed the purchasing habits of consumers, but has dramatically transformed the way in which manufactured goods are delivered to end-users. In the case of home and office furnishings, items that were once delivered pre-assembled from neighborhood department stores are now shipped unassembled using flat-pack methods from regional distribution facilities. Where individual cartons containing flat-pack furnishings reduce the cubic volume required to warehouse each product in a distribution center, along with allowing for easier transport via parcel delivery services, such furnishings consist of numerous components and hardware that are often difficult and counterintuitive to assemble. Accordingly, there is a need to provide an integrated approach to the design, manufacture, distribution and assembly of furnishings that is compatible with the current paradigm of order-fulfillment.
The primary disadvantage, inherent within prior art ready-to-assemble furnishings, concerns the extensive use of composite materials that consist of medium-density fiberboard (MDF) clad with high-pressure decorative laminates. MDF, often called “particle board,” is composed of wood fiber glued under heat and pressure to create a resilient grade of planar sheet stock. Although considered a sustainable source in the fabrication of furnishings, MDF board is a hygroscopic material that is prone to dimensional changes depending on the relative humidity and air temperature in the surrounding environment. When used in the construction of furnishings, the bonded composition of MDF board and high-pressure laminates may swell or delaminate when exposed to moisture. Aside from the multilayered composite materials used in the fabrication of flat-pack furnishings, exposed edges and decorative laminated surfaces are known to chip or crack in final assembly. Where high-pressure laminates are functional and durable, decorative veneers of this type are produced from thermosetting plastic resins that are formed and solidified under heat and pressure, thereby increasing the rigidity while diminishing the impact resistance of these materials. For this reason, the compressive force exerted through the utilization of dowel pegs, cam locks, and wood screws, found within the joinery and pre-drilled apertures of the prior art, has caused fragments of high-pressure laminates to break away from such ready-to-assemble furnishings.
The use of interchangeable horizontal and vertical planar components, having a corresponding arrangement of interlocking slot and tab elements, is also known in the art to assemble a variety of furnishings without the need for tools or fasteners. For example, U.S. Pat. Nos. 6,769,369, 8,220,398, and 8,667,911, respectively issued on Aug. 3, 2004, Jul. 17, 2012, and Mar. 11, 2014 to B. Brandenberg, describe modular furniture systems composed of interchangeable panels of uniform thickness. The planar components are reversible and may be reconfigured into different furniture pieces using a reciprocating pattern of interconnecting tabs, slots, and grooves to secure the panels together.
Similarly, U.S. Pat. No. 8,590,976, issued on Nov. 26, 2013 to C. Davis, discloses ready-to-assemble furnishings comprised of bendable panels that incorporate a series of interlocking joints having slot and tab components. The constituent slot and tab elements are disposed in misalignment to twist or displace the planar configuration of adjoining panels so as to secure the joint assembly without the use of additional fasteners. The modular furniture system further includes the adaptable use of interchangeable planar components within the same furniture article, or to create different furniture pieces.
Modular furniture systems assembled from interlocking panels have gained widespread acceptance within e-commerce channels of distribution, and the products are primarily purchased by families for use by young children. The simplicity of connecting and dismantling component pieces to create new articles of furniture is a fun and engaging activity that encourages curiosity and involvement for young people. Until now, however, the interlocking slot and tab elements used in prior art modular furniture systems have been left exposed on the exterior surfaces of such items, and has produced joinery that may be easily disengaged or tampered with. The mating of interlocking panels produces apertures between the fully assembled slot and tab elements, thereby creating pinch points for small fingers. Accordingly, there is a need to provide a modular furniture system that minimizes the exposure of slot and tab joinery, while offering a product that is both educational and easy to assemble.
The systems, methods, and inventions described in the above-identified patent publications are found lacking in disclosing an improved interlocking furniture system that reduces the appearance of slot and tab elements on the exposed surfaces of ready-to-assemble furnishings.
Accordingly, it is a principal object of the present invention to provide a modular furniture system having a complementary arrangement of interlocking panels that minimizes and hides the slot and tab joinery on ready-to-assemble furnishings.
It is a further object of the present invention to provide a modular furniture system incorporating the use of exterior interlocking panels that secure an arrangement of interior non-interlocking panels when fully assembled.
It is yet another object of the present invention to provide an arrangement of exterior interlocking panels incorporating the use of tab elements having a raised undercut to form an interference fit when fully inserted into a corresponding slot of an adjacent exterior panel.
Finally, it an object of the present invention to provide a modular furniture system having enclosable storage compartments that may be concealed with an arrangement of selectively movable and/or detachable panels.
SUMMARY OF THE INVENTION The limitations of the background art discussed above are overcome by the present invention. With this invention, an improved modular furniture system, composed of a complementary arrangement of interlocking and non-interlocking panels, minimizes the appearance of joinery formed by corresponding slot and tab elements. In a preferred embodiment, the modular furniture system comprises a configuration of non-interlocking interior panels that become secured into position through the means of interlocking exterior side and end panels. The interlocking panels employ the use of tab elements that produce an interference fit when fully engaged with a corresponding slot; alternatively, the tab elements may utilize a supplemental slot to provide a locking mechanism that resists disassembly of the tab and slot joinery. The corresponding use of the preferred tab and slot elements allows the assembly or disassembly of the interlocking and non-interlocking panels without the need for tools or fasteners. The modular furniture system is further manufactured from a combination of planar components that are interchangeable and symmetrical, and may be reconfigured into different pieces of furniture. The assembly of exterior and interior panels also forms enclosable storage compartments that may be concealed through the use of movable and detachable panels.
Further objects and advantages of the present invention will be apparent from the following description of the preferred embodiments when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front perspective view of a children's play table according to the present invention;
FIG. 2 is a front perspective view of the children's play table of FIG. 1 showing a concealed storage area and detached panel cover;
FIG. 3 is a front perspective view of the children's play table of FIG. 1 showing a detached panel cover oriented in attaching relation to a side panel of the present invention;
FIG. 4 is a front perspective view of the children's play table of FIG. 1 showing a panel cover attached to a side panel of the present invention;
FIG. 5 is an exploded view of the children's play table of FIG. 1 showing the disassembled components of the present invention;
FIGS. 6-7 are top plan views of the components of FIG. 5 on pieces of planar sheet stock according to the modular furniture system of the present invention.
FIGS. 8-9 illustrate the stacking and storage capabilities of the modular furniture system of the present invention;
FIG. 10 is a front perspective view of a coffee table according to an alternate embodiment of the present invention;
FIG. 11 is a front perspective view of the coffee table of FIG. 10 showing a concealed storage area and hinged panel covers;
FIG. 12 is a front perspective view of a desk having a concealed storage area according to an alternate embodiment of the present invention;
FIG. 13 is a front perspective view of a bed having detachable panel covers and concealed storage areas according to an alternate embodiment of the present invention;
FIG. 14 is a front perspective view of a crib having detachable panel covers and concealed storage areas according to an alternate embodiment of the present invention;
FIG. 15 is a perspective view of interchangeable panel covers according to the present invention.
FIG. 16 is a rear perspective view illustrating the interlocking slot and tab assembly of the prior art;
FIGS. 17a-17c are cross-sectional views of the assembly of a slot and tab joint design with a curvature of the undercut of the L-shaped tab, producing an interference fit according to a preferred embodiment of the present invention;
FIGS. 18a-18c are cross-sectional views of the assembly of a slot and tab joint design with a raised portion with a raised portion on the undercut of the L-shaped tab, producing an interference fit according to an alternate embodiment of the present invention; and
FIGS. 19a-19c are cross-section views of the assembly of a slot and tab joint design that provides a locking mechanism to resist disassembly of the assembled joint according to an alternate embodiment of the present invention.
Similar reference characters denote corresponding features consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1-5 in the drawings, a children's play table 10, made in accordance with the modular furniture system of the present invention, is illustrated. The play table 10 is an example of the type of ready-to-assemble furniture that can be fit together from interlocking panels using corresponding slot and tab elements without need for tools or fasteners. As explained herein, the modular furniture system allows a user to assemble, disassemble, and reconfigure a complementary arrangement of exterior and interior panels that hide the joinery formed by the slot and tab elements, while creating a large variety of aesthetically pleasing furnishings that also provide concealed storage areas. Furnishings assembled from the interchangeable and reversible components of the present invention are ideally suited for use where storage space is limited, and may include pieces such as tables, desks, cribs, mattress foundations, and other items.
As illustrated in FIGS. 1-5, the play table 10 is preferably rectangular and fit together from exterior side and end panels 11 and 12 having unequal adjacent sides that are located at right angles to one another. The geometry of the longer side panels 11 are identical to one another, each having an arrangement of four vertical slots 110 to receive connector tabs 120. The geometry of the shorter end panels 12 are also identical to one another, each having an arrangement of four L-shaped vertical interlocking connector tabs 120, and each including a configuration of four vertical slots 121 to receive the connector tabs 130 of interior top supporting panels 13, and the connector tabs 150 of interior bottom supporting panels 15. The four L-shaped vertical interlocking connector tabs 120 also project outward and then downward from each end panel 12 to form an interference fit when inserted within the vertical slots 110 of side panels H. In a preferred embodiment, and as shown as tab 120a in FIGS. 17a-17c, the L-shaped tabs 120 of end panels 12 may utilize a locking bump to ensure the secured assembly of the interlocking components should the table 10 be lifted, tilted, or rotated upside down. Alternatively, the exterior panels may be designed to produce a table having four equal sides, but composed of side panels having a greater length than the end panels, in order to compensate for the slot and tab joinery used in the ready-to-assemble article.
With further reference to FIGS. 1-5, the play table 10 has a complementary arrangement of two interior top supporting panels 13 that extend in parallel along side panels 11, and which are situated in parallel along the opposing interior sides of the table. The geometry of the top supporting panels 13 are identical to one another, each having an arrangement of three horizontal slots 131 to receive horizontal connector tabs 140 of top panel 14a. The top supporting panels 13 are maintained in position by vertical connector tabs 130, each corresponding with vertical slots 121 of end panels 12, and each of which are designed to slide easily into slots 121 without interlocking with end panels 12. In a preferred embodiment, the connector tabs 130 protrude beyond the planar exterior surfaces of end panels 12 to interface with U-shaped notches 161 formed into the perimeter of detachable panels 16. The connector tabs 130 of top supporting panels 13 may be shaped at one or both ends to suspend or store detachable panels 16 along the vertical surfaces of end panels 12. Alternatively, the connector tabs 130 may not extend beyond the planar surfaces of end panels 12.
In an additional embodiment, and as shown in FIGS. 1-5, the play table 10 also has a complementary arrangement of two interior bottom supporting panels 15 that extend in parallel along side panels 11, and which are situated in parallel along the opposing interior sides of the table. The geometry of the bottom supporting panels 15 are identical to one another, each having an arrangement of three horizontal slots 151 to receive horizontal connector tabs 140 of bottom panel 14b. The bottom supporting panels 15 are maintained in position by vertical connector tabs 150, each corresponding with vertical slots 121 of end panels 12, and each of which are designed to slide easily into slots 121 without interlocking with end panels 12. In a preferred embodiment, the connector tabs 150 do not protrude beyond the planar exterior surfaces of end panels 12. Alternatively, the connector tabs 150 may protrude beyond the planar exterior surfaces of end panels 12 to interface with a supplemental pair of U-shaped notches formed within the perimeter of detachable panels 16 (not shown). The connector tabs 150 of bottom supporting panels 15 may be shaped at one or both ends to help suspend or store detachable panels 16 along the vertical surfaces of end panels 12.
In a preferred embodiment, and as further illustrated in FIG. 5, the geometry of the horizontally oriented top and bottom panels 14a and 14b are identical to one another, with each having an arrangement of six horizontal connector tabs 140, which either insert into the horizontal slots 131 of the two interior top supporting panels 13, or into the horizontal slots 151 of the two interior bottom supporting panels 15. The horizontal connector tabs 140 of either top or bottom panels 14a or 14b, are designed to easily slide into horizontal slots 131 or 151, without interlocking with supporting panels 13 or 15, respectively. In an alternate embodiment, the four interior supporting panels 13 and 15 may consist of just two vertically oriented interior support panels (not shown) that extend in parallel along side panels 11, and which are situated in parallel along the opposing interior sides of play table 10. Each vertically oriented interior support panel has an arrangement of six horizontally oriented slots that are positioned in similar relation to the horizontal slots 131 and 151, of supporting panels 13 and 15, in the preferred embodiment. The horizontal tabs 140 of either top or bottom panels 14a or 14b are similarly designed to slide into the horizontal slots formed within each vertically oriented interior support panel without interlocking. Moreover, the two interior support panels of the alternate embodiment may be similarly maintained in position by vertical connector tabs that correspond with the vertical slots 121 of end panels 12, each of which are designed to slide easily into slots 121 without interlocking with end panels 12, and each of which are analogous in shape to the vertical connector tabs 130 and 150 of interior support panels 13 and 15, respectively. The horizontal connector tabs 140 of either the preferred or alternate embodiment do not extend beyond the outermost planar surfaces of the interior support panels, to allow the joinery formed by the slot and tab elements to remain hidden behind side panels 11.
Referring once again to FIGS. 1-5, the play table 10 is assembled from a complementary arrangement of non-interlocking interior panels 13, 14a, 14b and 15, which become secured into position through the means of interlocking exterior side and end panels 11 and 12. In a preferred embodiment, the exterior side and end panels 11 and 12 are of uniform thickness; alternatively, the arrangement of four vertical slots 110, located within each side panel 11, may be adjusted to accommodate a dissimilar thickness of end panels 12 in comparison to the thickness of side panels 11. The non-interlocking interior panels 13, 14a, 14b and 15 may be of the same thickness as exterior side and end panels 11 and 12. In a preferred embodiment, the interior top and bottom supporting panels 13 and 15 must be of equal thickness to each other, but may be of dissimilar thickness in comparison to the exterior side and end panels 11 and 12. Additionally, the top and bottom supporting panels 13 and 15 may be of dissimilar thickness in relation to the thickness of interior top and bottom panels 14a and 14b. The exterior and interior panels used in the assembly of the preferred and alternate embodiments of present invention may be composed of similar or dissimilar planar materials. For example, play table 10 may consist of natural or composite wood sheets such as: solid hardwood or softwood; plywood; particle board; or MDF board. Moreover, acrylic, plastic, glass or metal sheets may also be utilized in the production of the panels, but the use of pre-finished melamine-coated plywood and high quality birch plywood is most preferred. The exterior and interior panels may also be finished differently on opposing sides to allow the user to choose the appearance of the assembled item.
As further depicted in FIGS. 1-5, an upper enclosable storage compartment and lower accessible shelving area of play table 10 are formed through the assembly of the exterior and interior panels of the present invention. The volume of the upper enclosable storage compartment is defined through the assembly of the two interior supporting top panels 13, the horizontally oriented interior top panel 14a, and the end panels 12. The storage compartment may also be partitioned into smaller sections through the use of halved joint dividers. As seen in FIG. 7, the dividers 18 and 19 may be produced concurrently with the exterior and interior panels of play table 10. The upper storage volume may be enclosed through the use of detachable and selectively movable panels 16 and 17, which are maintained in sliding relation along the facing edge portions of the top supporting panels 13. The lower accessible shelving area of play table 10 is similarly defined through the assembly of the two bottom interior supporting panels 15, the horizontally oriented interior bottom panel 14b, and the exterior end panels 12.
As illustrated in FIGS. 1-5 and 15, the present invention incorporates the use of three detachable panels, with two smaller panels 16 located adjacent to a larger detachable panel 17. Although fewer or additional panels may be used to enclose the upper storage compartment of play table 10, the smaller panels 16 may be interchanged with panels 26a, 36 and 46, each having U-shaped notches 161, 261, 361 and 461, respectively, which are formed within the perimeter of each detachable panel. The U-shaped notches 161, 261, 361, or 461, may also consist of blind cutouts that do not extend through the thickness of the detachable cover panels (not shown). The detachable panels 16, 36 and 46, may incorporate openings 160, 362, or 460 to facilitate easy lifting by hand; alternatively, the geometry of the panels may also include diagonal edges 262 to assist in removal. With further reference to FIGS. 10-11, and by way of example, two or more of the detachable cover panels 26b and 27 may be attached to one another using one or more hinge mechanisms 263, thereby preventing removal of an individual panel but allowing the detachable panels to pivot in relation to one another.
Referring now to FIGS. 6-7 in the drawings, the geometry for all of the required component pieces of play table 10 are illustrated on 48-inch by 72-inch panels for production on a computer numerical control (CNC) router system. The router pattern layouts of work pieces 11, 12, 13, 14a, 14b, 15, 16, 17, 18, and 19 are detailed, and are preferably fabricated from planar materials of uniform thickness to minimize the number of different machining processes required for manufacture. Such layouts also ensure that material is efficiently used to manufacture the components of the present invention. This feature has the following advantages: (1) no post-machining assembly is performed, so the amount of material handling and number of required machining operations is minimized, reducing the total cost of manufacture; (2) final components can be produced from raw material in one machining step; (3) the planar design makes machining very suitable for two-axis machining processes such as computer numerical control (CNC) routers; (4) flat pieces may be packed and shipped using flat-pack methods which minimizes the total size of the shipping package (see FIGS. 8 and 9); and (5) flat pieces allow for more compact storage by the user before assembly or after disassembly. It should be understood that other layouts for furniture articles composed of variable planar thicknesses may also be used.
The preferred and alternate embodiments of the present invention may be utilized to make other furniture articles. For example, as shown in FIGS. 10-11, the provisions used in the fabrication and assembly of play table 10 may be incorporated to make a coffee table 20. Like the play table, the coffee table 20 is generally rectangular and fit together from exterior side and end panels 21 and 22 having adjacent sides that are located at right angles to one another. The geometry of the longer side panels 21 are identical to one another, each having an arrangement of four vertical slots 210 to receive connector tabs 220. The geometry of the shorter end panels 22 are also identical to one another, each having an arrangement of four L-shaped vertical interlocking connector tabs 220, and each including a configuration of two vertical slots 221 to receive connector tabs 230 of interior support panels 23. Unlike play table 10, the coffee table 20 has only one set of interior panels 23 to support only one interior horizontal panel 24. The four L-shaped vertical interlocking connector tabs 220 also project outward and then downward from each end panel 22 to form an interference fit when inserted within the vertical slots 210 of side panels 21. In a preferred embodiment, and as depicted as tab 120a in FIGS. 17a-17c, the L-shaped tabs 220 of end panels 22 may utilize a locking bump to ensure the secured assembly of the interlocking components should the coffee table 20 be lifted, tilted, or rotated upside down. Alternatively, the exterior panels may be designed to produce an end table (not shown) having four equal sides, but composed of side panels having a greater length than the end panels, in order to compensate for the slot and tab joinery used in the ready-to-assemble article. As further seen in FIGS. 10-11, the coffee table 20 implements the same method of assembly as play table 10, using a complementary arrangement of non-interlocking panels 23 and 24, which become secured into position through the means of interlocking side and end panels 21 and 22. The non-interlocking panels 23 and 24 are also identical in geometry as non-interlocking top supporting panels 13, along with panels 14a or 14b, of play table 10. In a preferred embodiment, the exterior side and end panels 21 and 22 are of uniform thickness, although the arrangement of four vertical slots 210, located in each side panel 21, may be adjusted to accommodate a dissimilar thickness of end panels 22 in comparison to the thickness of side panels 21. The non-interlocking panels 23 and 24 may also be of the same or dissimilar thickness as exterior side and end panels 21 and 22.
As further illustrated in FIG. 11, an enclosable storage compartment of coffee table 20 is formed through the assembly of the exterior and interior panels of the present invention. The volume of the storage compartment is defined through the assembly of the two interior supporting panels 23, the horizontally oriented interior panel 24, and the end panels 22. The storage compartment may also be partitioned into smaller sections through the use dividers (not shown). The storage volume may be enclosed through the use of detachable and selectively movable panels 26b and 27, which are maintained in sliding relation along the facing edge portion of the supporting panels 23. As in the embodiments disclosed for play table 10, the coffee table 20 incorporates the use of three detachable panels, with two smaller panels 26b located adjacent to a large detachable panel 27, which is positioned in the middle of the coffee table. Although fewer or additional panels may be used to enclose the storage compartment, the smaller panels 26b may be interchanged with panels 16, 26a, 36 or 46 seen in FIG. 15; alternatively, the detachable panels 26b and 27 may be attached to one another using a hinge mechanism 263 to pivot in relation to one another.
With reference to FIG. 12 in the drawings, the planar components of the present invention may be scaled to produce a variety of different furnishings to suit any number of environments. For example, the height of the exterior side and end panels in coffee table 20 may be increased to create a desk 30; alternatively, the design may be re-scaled to produce a workbench or tool bench with a storage compartment. Similar to the coffee table, desk 30 is also rectangular and fit together from exterior side and end panels 31 and 32, respectively, having adjacent sides that are located at right angles to one another. The geometry of the longer side panels 31 are identical to one another, each having an arrangement of four vertical slots 310 to receive connector tabs 320. The geometry of the shorter end panels 32 are also identical to one another, each having an arrangement of four L-shaped vertical interlocking connector tabs 320, and each including a configuration of two slots (not shown) to receive connector tabs 330 of interior supporting panels 33. Like coffee table 20, the desk 30 has only one set of interior panels 33 to support only one interior horizontal panel 34. The four L-shaped vertical interlocking connector tabs 320 also project outward and then downward from each end panel 32 to form an interference fit when inserted within the vertical slots 310 of side panels 31. In a preferred embodiment, and as shown as tab 120a in FIGS. 17a-17c, the L-shaped tabs 320 of end panels 32 may utilize a locking bump to ensure the secured assembly of the interlocking components should the desk 30 be lifted, tilted, or rotated upside down. The desk 30 implements the same method of assembly as coffee table 20, using a complementary arrangement of non-interlocking panels 33 and 34, which become secured into position through the means of interlocking side and end panels 31 and 32. The non-interlocking panels 33 and 34 are also identical in geometry as non-interlocking panels 23 and 24 of coffee table 20. In a preferred embodiment, the exterior side and end panels 31 and 32 are of uniform thickness, although the arrangement of four vertical slots 310, located in each side panel 31, may be adjusted to accommodate a dissimilar thickness of end panels 32 in comparison to the thickness of side panels 31. The non-interlocking panels 33 and 34 may also be of the same or dissimilar thickness as exterior side and end panels 31 and 32.
As shown in FIG. 12, an enclosable storage compartment of desk 30 is formed through the assembly of the exterior and interior panels of the present invention. The volume of the storage compartment is defined through the assembly of the two interior supporting panels 33, the horizontally oriented interior panel 34, and the end panels 32. The storage compartment may also be partitioned into smaller sections through the use of dividers (not shown). The storage volume may be enclosed through the use of detachable and selectively movable panels 36 and 37, which are maintained in sliding relation along the facing edge portion of the interior supporting panels 33. As in the embodiments disclosed for the coffee table 20, the desk 30 incorporates the use of three detachable panels, with two smaller panels 36 located adjacent to a larger detachable panel 37, which is positioned in the middle of the desk 30. The two detachable panels 36 may be modified with slot cuts 371 to accommodate the pass through of computer cables, the panels 36 each have U-shaped notches 361 formed within the perimeter of each detachable panel so that they may be suspended by connector tabs 330 for storage. The panels 36 may be interchanged with panels 16, 26a, or 46 seen in FIG. 15. Alternatively, the detachable panels 36 and 37 may be attached to one another using a hinge mechanism (not shown) to pivot in relation to one another.
The geometry of the interlocking components of the present invention may also be modified to create furniture articles having multiple storage areas, which are ideally suited for use within environments where storage space is limited. For example, and as illustrated in FIG. 13, the panels used in the fabrication of play table 10, shown in FIGS. 1-5, may be elongated to make a mattress foundation for a bed. Like the play table, the mattress foundation 40 is generally rectangular and fit together from exterior side and end panels, however, in this embodiment the end panels 12 of play table 10 have been extended to make side rails 42, and the side panels 11 of play table 10 have been adapted to make head and footboard components 41a, 41b and 41c. The geometry of the head and footboard components 41a, 41b, and 41c are not identical to one another, but panels 41a and 41c each have an arrangement of four vertical slots 410 to receive connector tabs 420 of side rails 42. The geometry of side rails 42 are identical to one another, each having horizontally oriented openings that provide access to a storage area within the mattress foundation 40, and each having an arrangement of four L-shaped vertical interlocking connector tabs 420. The side rails 42 are also fabricated with an upper configuration of vertical slots (not shown) to receive the connector tabs 430 of six interior top supporting panels (not shown), which provide reinforcement for removable panels 46. Side rails 42 additionally include a bottom configuration of two lower vertical slots (not shown), located near the head and footboard of the bed, which interface with two interior bottom supporting panels 45, and extend in parallel along the head and footboard panels 41b and 41c. The four L-shaped vertical interlocking connector tabs 420, of each side rail 42, also project outward and then downward to form an interference fit when inserted within the vertical slots 410 of panels 41a and 41c. In a preferred embodiment, and exemplified as tab 120b in FIGS. 18a-18c, the L-shaped tabs 420 of side rails 42 may utilize a locking bump to ensure the secured assembly of the interlocking components.
As further shown in FIG. 13, enclosable storage compartments of the mattress foundation 40 are formed through the assembly of the exterior and interior panels of the present invention. The volume of the storage compartments are defined through the assembly of bottom supporting panels 45, the horizontally oriented interior panel 44, the head and footboard components 41b and 41c, and removable panels 46. The storage volume may be enclosed through the use of detachable panels 16, each having an opening 160 to facilitate easy lifting by hand. Moreover, the detachable panels 16 each have U-shaped notches 161 formed within the perimeter of each panel, which are used to removably interface with vertical connector tabs 430. The storage volume may also be accessed through removable panels 46 that also provide support for a box spring and mattress. The panels 46 additionally feature the use of U-shaped notches 461, along with openings 460, to assist in the handling of the removable components.
Referring now to FIG. 14 in the drawings, the modular components of the mattress foundation 40 may be scaled to produce a crib. Like the mattress foundation, the crib 50 is generally rectangular and fit together from side rail panels 52 along with head and footboard panels 51. The geometry of the head and footboard panels 51 are identical to one another, each having an arrangement of four vertical slots 510a to receive connector tabs 520a, and each having a configuration of four vertical slots 510b to receive connector tabs 520b. The geometry of side rail panels 52 are also identical to one another, each having an arrangement of four L-shaped vertical interlocking connector tabs 520a, which project outward and then downward to form an interference fit when inserted within the vertical slots 510a of head and footboard panels 51. In a preferred embodiment, and as exemplified as tab 120c in FIGS. 19a-19c, the L-shaped tabs 520a may utilize a separate slot 741 for interlocking panels 51 and 52, respectively, to provide a safety mechanism that resists disassembly of the joint in reverse order of assembly. The corresponding configuration of vertical slots 510b and connector tabs 520b, the interior support rails of which are designed to raise or lower a mattress (not shown), may also incorporate the safety mechanism disclosed in FIGS. 19a-19c. The side rail panels 52 are also fabricated with an upper arrangement of four vertical slots (not shown) to receive connector tabs 530 of two interior top supporting panels (not shown), and two interior bottom supporting panels 55, which extend in parallel along the head and footboard panels 51.
As further shown in FIG. 14, enclosable storage compartments of crib 50 are formed through the assembly of the exterior and interior panels of the present invention. The volume of the storage compartments are defined through the assembly of bottom supporting panels 55, the horizontally oriented interior panel 54, the head and footboard panels 51, and an upper mattress support panel (not shown). The storage volume may be enclosed through the use of detachable panels 16, each having an opening 160 to facilitate easy lifting by hand. Moreover, the detachable panels 16 each have U-shaped notches 161 formed within the perimeter of each panel, which are used to removably interface with vertical connector tabs 530. [0052] The combination of the exterior and interior panels of crib 50, along with other furnishings assembled according to the present invention, hides the joinery formed by the slot and tab elements which, heretofore, have been left exposed on the exterior surfaces of prior art modular furniture systems. As illustrated in FIG. 16, slot and tab elements of the prior art have produced joinery that may be easily disengaged or tampered with by young children. For example, the mating of panels 61, 62, and 64, through the means of vertical slot and tab joinery 610 and 620, along with horizontal slot and tab joinery 630 and 640, have produced exposed apertures between the assembled slot and tab elements that are pinch points for young fingers. The complementary arrangement of exterior and interior panels to hide such joinery, along with the preferred use of the slot and tab means described below, minimizes the existence of pinch points in the assembly of interlocking panels.
In the following descriptions, the term “design” is generally used to refer to the general shape of the members being assembled to form the slot and tab joinery, but does not refer to the exact dimensions of the shapes. “Specification” is generally used to refer to a particular implementation of a joint design, where the exact shape dimensions and tolerances need be specified for a particular material in a specified range of acceptable thickness.
In a preferred embodiment, the end panels 12 as shown on FIG. 1 may utilize an L-shaped tab 120 having a locking bump to keep the table securely assembled should the table be lifted, tilted or rotated on its side or upside down. The locking bump prevents the L-shaped tab 120 from being easily disengaged by relying on the flexure of the mating panel to provide resistance against the L-shaped tab being urged sideways. As illustrated in FIGS. 17a-17c, and as further explained in U.S. Pat. Nos. 8,220,398 and 8,667,911, the interference bump on the undercut of an L-shaped tab 120a produces a joint with a loose fit at the start of engagement, and an interference fit once the material around the slot 110 has engaged the bump. In this joint design, the bump is positioned to provide an interference fit over the majority of the engagement length of the joint. For any material thickness in the range between the minimum and maximum thickness specified for a particular joint specification, this design provides for easy alignment of a tab 120a and slot 110, and allows the undercut of the L-shaped tab 120a to begin engaging the material around the slot 110 before any significant assembly force is required, making part alignment during assembly easier for the user. Depending on the thickness, elasticity and compressibility of the material, assembly force will increase as the material around the slot engages the bump, but will remain uniform throughout the completion of joint assembly until the material around the slot 110 fully engages the crotch of the tab 120a. This joint design yields a securely assembled joint and is well suited to harder materials such as birch plywood, because the material thickness tolerances dictated by manufacturing standards such as Gosstandart (GOST), and the elasticity and compressibility of the material match well with the tolerances and interference characteristics of this particular joint design. It should be understood that the bump does not have to be integral to the panel material, but could be produced by an insert made of wood, plastic, metal, or other material. Inserts made of soft materials such as wood or plastic may deform more in an interference fit situation than harder materials like metal, causing less permanent disfiguration to the mating panel. FIGS. 17a-17c depict the use of a bumped surface as part of an L-shaped tab 120a. FIG. 17a illustrates a close fit, while FIGS. 17b and 17c detail an interference fit. Graphs 625, 627, and 629 generally illustrate the assembly force required. In FIGS. 17a, 17b, and 17c, the tab 120a is a single specification. The material that is utilized to form the slot varies in thickness. FIG. 17a utilizes a material for the slot that has a thickness 11a. FIG. 17b utilizes a material for the slot that has a thickness of 11b. FIG. 17c utilizes a material for the slot that has a thickness of 11e.
In an alternate embodiment, and with further reference to U.S. Pat. Nos. 8,220,398 and 8,667,911, side rails 42, shown in FIG. 13, may utilize and L-shaped tab 420 having a locking bump that is positioned on the undercut to produce a joint with a loose fit at the start of engagement, and an interference fit once the material around the slot 410 has engaged the bump. As shown in FIGS. 18a-18c, the bump is positioned to provide an interference fit over a fraction of the engagement length of the joint, hence minimizing the distance over which force must be exerted to fully assemble the joint. For any material thickness in the range between the minimum and maximum thickness specified for a particular joint specification, this design provides for easy alignment of a tab 120b and slot 110, and allows the undercut of the L-shaped tab 120b to begin engaging the material around the slot 110 before any significant assembly force is required, making part alignment during assembly easier for the user. Depending on the thickness, elasticity and compressibility of the material, assembly force will increase as the material around the slot engages the bump, but will remain uniform throughout the completion of joint assembly until the material around the slot 110 fully engages the crotch of the tab 120b. This joint design yields a securely assembled joint and is well suited to harder materials such as birch plywood, because the material thickness tolerances dictated by manufacturing standards such as GOST, and the elasticity and compressibility of the material match well with the tolerances and interference characteristics of this particular joint design. FIGS. 18a-18c illustrate the use of a bumped surface as part of an L-shaped tab 120b. FIG. 18a illustrates a close fit, while FIGS. 18b and 18c depict an interference fit. Graphs 631, 633, and 635 generally illustrate the assembly force required. In FIGS. 18a, 18b, and 18c, the tab 120b is a single specification. The material that is utilized to form the slot varies in thickness. FIG. 18a utilizes a material for the slot that has a thickness 11a. FIG. 18b utilizes a material for the slot that has a thickness of 11b. FIG. 18c utilizes a material for the slot that has a thickness of 11e.
In yet a further alternate embodiment, and with additional reference to U.S. Pat. Nos. 8,220,398 and 8,667,911, the side rail 52 of FIG. 14 may utilize a separate slot 741 for locking the planar components to assemble the joint. As exemplified in FIGS. 19a-19c, the separate slot 741 can be located anywhere on the panel and does not have to be near an existing tab of a slot 110. FIGS. 19a and 19b detail a tab 120c inserted into a slot 110 with surfaces S5 and T5 in engagement. FIG. 19b shows a tab 120c moved relative to a slot 110 with surface T1 of tab 120c making contact with surface S1, and surface S2 making contact with raised portion 743 of surface T2. The design causes the mating panel to flex during assembly, and then snap into the slot to provide a locking mechanism that resists disassembly of the joint in reverse order of assembly. FIG. 19c demonstrates a slot 110 and tab 120c fully engaged and locked into position by surface S5 of slot 741 engaging the shoulder of raised portion 743. The shape of the raised portion 743 may be varied to change the resistance characteristics of the locking mechanism. By making the raised portion 743 higher, the amount of force required to disassemble the joint can be increased.
Even though numerous characteristics and advantages of the present invention has been set forth in the foregoing description, together with details of the structure and function of the preferred embodiments, the above disclosure is illustrative only. Changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad and general meaning of the terms in which the appended claims are expressed.
