Patent Application
20060225627
Not applicable.
Not applicable.
The field of the invention is work surfaces and more specifically steel laminated work surfaces having a matrix type internal structure.
From a design perspective, a planar member used to form a work surface structure should ideally have certain characteristics and working properties. First, a planar member used to form a work surface should provide a completely flat surface as the work surface without any imperfections (i.e. bumps, ripples, grain patterns, cracks, etc.).
Second, a planar member for providing a work surface should be extremely stiff and should not bend when anticipated forces are applied thereto. In this regard, ideally the planar member is at least somewhat self supporting so that if an edge of the planar member extends past (e.g., two plus feet) a supporting leg there below, the edge of the member will not bend when force is applied thereto. Similarly, if member supporting legs are separated by several feet (e.g., six feet), a central section of the planar member should not bend when force is applied thereto.
Third, a planar member for providing a work surface should be workable into many different shapes including rectilinear shapes, curved shapes and other desirable shapes so that the member can be used in many different and diverse applications. For instance, in one application one end of a planar work surface member may be rectilinear while the opposite end may have a rounded and substantially circular shape.
Fourth, a planar member used to form a work surface should have a minimal thickness to increase the number of available design options. Here, where a specific design requires a thin table top, the planar member can be used and where another design required a thicker table top, two or more of the planar members can be stacked or one of the planar members can be stacked with some other type of flat member (e.g., non-structural) to provide the desired effect.
Fifth, a planar member for providing a work surface is ideally light weight so that the member can be used in many different applications.
Sixth, a planar work surface forming member should have a top surface that can be finished with many different finishes. For instance, in some applications it may be desirable to have a wood work surface finish while in other cases a metallic finish, a ceramic finish, a plastic finish, a rubber finish, etc., may be desired.
Seventh, an ideal planar work surface forming member should be easy to manufacture so that cost can be minimized.
The table and work space industries have attempted to provide planar members that have the optimal characteristics above but each attempt has had one or more shortcomings. To this end, while many different finishing coverings or layers can by applied to wood and wood can generally be processed to provide precisely flat work surfaces, in order to provide sufficient stiffness for many work surface applications, wood often has to be relatively thick and can be relatively heavy. In addition, because stock wood typically comes in dimensions that are less than work surface dimensions, it is relatively difficult to form at least some desirable work surface shapes out of planar wood material.
To overcome some of the limitations associated with wood as a work surface material, the industry has extensively used laminates that include several thin layers of wood or other fibrous material that are glued together. Laminated materials can be configured in virtually any shape and size, are easy to manipulate and use in manufacturing processes and can be finished with many different top layers. Unfortunately, to provide laminated work surface members that are sufficiently stiff for some applications, the laminated members have to be relatively thick (e.g., 1⅛ inches thick) and are often relatively heavy and hence difficult to work with.
Planar work surface members have been designed that have two spaced external sheets or skins of metal or the like and an embossed or formed sheet (hereinafter “the waffle layer”) therebetween that forms a “waffle pattern” intended to lend rigidity and strength to the assembly while allowing the assembly to remain relatively light weight. Hereinafter, unless indicated otherwise, these three layer arrangements will be referred to as “waffle assemblies”. In these prior waffle assemblies the inner rigidity imparting sheet has usually been formed or embossed to have a plurality of indentations on each side so that the sheet has a plurality of elevations on each side, terminating in relatively flat plateaus or lands to which the spaced skins are secured by welding or the like.
These waffle assemblies have several advantages. Specifically, like woods and laminates, waffle assemblies can be used to form flat work surfaces. In addition, waffle assemblies, like laminates, can be formed into virtually any shape and size. Moreover, minimally thick and relatively light weight waffle assemblies can provide greater stiffness than similarly thick laminate and wood members. Stiffness and rigidity can be maximized by forming the waffle layer to have a large number or lands that extend in either direction so that many points of contact exist between the waffle layer and the skins. This is particularly important proximate the edge sections of a waffle assembly so that edges of the skins are sufficiently supported.
Shortcomings with waffle assemblies generally have to do with the manufacturing processes used to form the assemblies. To this end, as well known in the metal working arts, when sheet metal is stretched beyond a threshold level, the metal tears or rips and the sheet has to be scrapped. Known prior art references teach that the middle waffle layer can be embossed in one of two ways. First, the waffle layer can be embossed by a die-shaping procedure wherein a flat middle sheet is fed from the sheet margins toward the center of the sheet during the forming process as the middle of the sheet is die pressed to form the lands. Here, the middle sheet material only stretches minimally and tears and the like occur to a lesser extent. While this die-shaping procedure results in fewer scrap pieces, the procedure causes material shrinkage as the margins of the middle sheet are drawn in toward the central portion thereof during the die-shaping process. Shrinkage is problematic as the shape of the resulting waffle layer is difficult to predict and the resulting waffle layer is difficult to cut into required shapes without deforming the waffle pattern generally.
Second, the waffle layer can be formed via a stretch-forming process by rigidly anchoring the margin portions of the middle sheet and striking or stretching the sheet via coacting dies to form the lands and the waffle pattern in general. Here, because the margins are anchored, the middle sheet does not shrink during shaping and an end shape for the waffle layer can be cut out prior to the embossing activity. Unfortunately, in the case of a waffle layer having a land pattern that provides a desired amount of stiffness and rigidity, it has been recognized that the amount of stretching required to form the waffle layer exceeds the stretching threshold level in at least some parts of the middle sheet during formation and therefore tearing or other irregularities routinely occur.
Another manufacturing shortcoming has to do with how to bond the waffle assembly skin layers to the waffle layer. The prior art contemplates several different ways to bond the skins to the waffle layer including welding and cementing. On one hand, cementing typically requires larger lands than welding to provide sufficient bonding activity and therefore reduces the overall number of lands that can be formed for a given work surface area. Welding, on the other hand, requires smaller lands and therefore can be used to increase the number of lands and hence member stiffness but can result in discontinuities (i.e., bumps, recesses, etc.) in the resulting work surface where the welding activity occurs.
One other manufacturing difficulty is related to how to finish the top surface of the skin that forms the work surface of a waffle assembly. In this regard, in many cases, it is relatively expensive to apply a finishing layer or coating (e.g., paint, ceramic, etc.) to separate work surface forming skins in a piecewise fashion. Nevertheless, where welding is used to secure the skin to a waffle layer, piecewise application of finishing layers after welding is necessary as the heat associated with welding would damage or destroy most finishes applied prior to welding.
In addition to the manufacturing issues related to waffle assembly type work surface members, one other problem is how to finish the edges of the waffle assembly. While various flexible nosing systems have been devised for more conventional type table tops (e.g., laminated tops, etc.), no known finishing edge treatment is known that addresses the particular needs of a waffle type assembly. In this regard, in addition to providing a finished appearance for the waffle assembly edge, a suitable edge treatment should provide support for the skin members along the edge as the lands proximate the edge typically are not fully supported and hence stiffness at the edges is often less than required for certain applications.
Still one other problem with a waffle assembly is how to mount supporting structure such as legs, pedestals, etc. thereto in an aesthetically acceptable manner. In this regard, while supporting structure must be rigidly mounted to the undersurface of a waffle assembly in many applications, for both functional as well as aesthetic reasons, the mounting structure should not be noticeable from the top working surface. Where a leg is to be mounted to the undersurface of a waffle assembly by four bolts that extend upward through a flange at the top of the leg, the bolts therefore must terminate within the thickness of the waffle assembly and hence can only be anchored to the bottom skin and/or the waffle layer which makes for a relatively flimsy mount.
Thus it would be advantageous to have a work surface forming assembly that is light weight, thin, extremely stiff and rigid, workable into many different shapes and sizes, is easy to manufacture and that can be finished in variable ways. In addition, it would be advantageous to have an edge trim configuration suitable for use with a waffle assembly type member and a suitable way to mount legs or other support structure to the underside of a waffle assembly type structure. Moreover, it would be advantageous to have a method that facilitates configuration of multiple work surface types having the aforementioned characteristics.
The foregoing needs are met by the present invention which provides a stiff, lightweight, two skin worksurface configuration capable of being produced in many of the same sizes and shapes of traditional worksurface configurations, such as rectangles, ovals, “L” shaped, etc., worksurface configurations, with minimal thickness. In at least some embodiments, the worksurface configuration includes: (a) a core matrix including (i) a first group of spaced coplanar top lands defining a first bearing surface of the core matrix, (ii) a second group of spaced coplanar bottom lands defining a second bearing surface of the core matrix, the first bearing surface and the second bearing surface being arranged in spaced apart relationship, and (iii) a bridging structure connecting the first group of spaced coplanar top lands and the second group of spaced coplanar bottom lands, the bridging structure having throughholes arranged around each land of the first group so that at least some of the throughholes are arranged inline between lands of the first group and adjacent lands of the second group; and (b) a top sheet bonded to the first group of spaced coplanar lands; and (c) a bottom sheet bonded to the second group of spaced coplanar lands.
The bridging structure of the core matrix includes curvilinear regions between adjacent top lands of the first group, and curvilinear regions between adjacent lands of the second group. In some cases, the curvilinear regions are saddle shaped. The top sheet may include a top surface layer comprising a material selected from ceramic coatings, polymeric coatings, laminates, and metallic coatings. Individual top lands are preferably dimensioned to have a larger surface area than individual bottom lands. In some cases, the top lands are circular and the bottom lands are circular.
The shape and design of the core matrix of the worksurface configuration provides for frequent connection to the top sheet and the bottom sheet minimizing local weaknesses in the worksurface configuration top. Also, the shape of the core matrix provides high strength through the double saddle form effectively connecting each attachment location, that is, the top lands and the bottom lands. Furthermore, a larger surface area for the top lands is advantageous in that this provides a larger surface area for adhesive bonding which is preferred to minimize damage to any surface finish applied to the top sheet. In the case of the bottom sheet, smaller lands will suffice in at least some applications as welding or other mechanical securing structure may be used.
The present invention also includes an edge treatment configuration that provides a method for finishing the edge of a worksurface configuration and that is compatible with the various geometric shapes mentioned above. The edge treatment configuration includes a flexible steel edge channel that is bonded or otherwise secured to a perimeter area of the bottom skin described above in at least some applications. This edge channel is capable of following the perimeter area through relatively tight internal and external bends. It is this flexibility that makes the edge treatment configuration compatible with the various geometries. Also, the edge channel may be formed from steel such that the edge channel is 100% recyclable.
The edge channel meets several functional requirements. First, the edge channel provides a structural connection between the upper and lower skins. This is essential in producing a stiff worksurface configuration that is capable of sustaining edge loads without a significant amount of deflection. Second, the edge channel can receive various finishing edge members including edge banding, edge molding, etc. The edge channel accomplishes this via a generally “C” shaped geometry. The lower surfaces of the edge channel are designed to be welded or otherwise secured to the bottom skin. The upper surfaces of the edge channel are designed to be bonded with adhesive or otherwise secured to the upper skin. Both the upper and lower surfaces of the edge channel may have offset sections. These offset section are designed to receive mounting fingers of an edge member. In at least some cases the offset sections include sharp barbs or points that are designed to penetrate into the edge member and securely hold the edge member in place.
The present invention also provides a system for mounting a component(s) (e.g., legs) to a worksurface configuration having a first sheet and a second sheet arranged to form an interior space in the worksurface configuration. The component mounting system includes a spacer having a side wall and a flange extending away from an edge of the side wall of the spacer. The spacer is dimensioned to fit in the interior space in the worksurface configuration. The component mounting system also includes at least one fastener for mounting the component to the first or second sheet of the worksurface configuration. Each fastener is suitable for extending through the sheet and engaging the flange of the spacer.
In one form, the spacer includes a top wall, and the spacer is dimensioned such that the top wall contacts an interior surface of the first sheet of the worksurface configuration and the flange contacts an interior surface of the second sheet of the worksurface configuration when the spacer is placed in the interior space in the worksurface configuration. In another form, the spacer includes a top wall and four side walls extending downwardly from the top wall. Each side wall terminates at its bottom in a lower edge of the spacer, and a flange extends outwardly from each lower edge of the spacer. The top wall contacts an interior surface of the first sheet of the worksurface configuration and the flanges contact an interior surface of the second sheet of the worksurface configuration when the spacer is placed in the interior space in the worksurface configuration. As a result, the spacers provide a further stiffening mechanism for the spaced apart first and second sheets of the worksurface configuration.
The component mounting system further includes a mounting bracket attached to the component. The mounting bracket has holes for receiving fasteners (e.g., screws), and the flanges of the spacer also have holes for receiving fasteners. When the component is mounted to the worksurface configuration, the holes formed by the spacer flanges align with the holes in the bracket.
The present invention also provides a method of manufacturing a worksurface configuration. In the method, a blank of planar sheet metal is first formed. The blank of planar sheet metal has central sections and throughholes arranged around a perimeter of each central section. The central sections form columns and rows. The blank is then deformed such that a first subset of the central sections in every other column and in every other row are used to form a first group of spaced coplanar lands at one side of the core matrix and such that a second subset of the central sections including central sections located between central sections from the first subset form a second group of spaced coplanar lands at an opposite side of the core matrix.
A second sheet is then welded to the second group of spaced coplanar lands. A plurality of spacers having a top wall, side walls connected to the top wall and lower flanges outwardly extending from the side wall are mounted to the second sheet by way of flanges like those described above. An edge channel is then secured to a perimeter area of the second sheet so that the edge channel forms an outward opening. A first metallic sheet is adhesively bonded to the first group of spaced coplanar lands, the top walls of the spacers, and the top surface of the edge channel. An edge member is then inserted in the opening of the edge channel. Support legs are next mounted on the second sheet by fasteners that engage the lower flange of a spacer.
These and other objects, advantages and aspects of the invention will become apparent from the following description. In the description, reference is made to the accompanying drawings which form a part hereof, and in which there is shown an example embodiment of the invention. Such embodiment does not necessarily represent the full scope of the invention and reference is made therefor, to the claims herein for interpreting the scope of the invention.
Like reference numerals will be used to refer to like or similar parts from Figure to Figure in the following description of the drawings.
Specific embodiments of the present invention will now be described. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
In
In the exemplary embodiment of the worksurface configuration 10, bottom sheet 42 is a flat rigid sheet type member formed of about 0.030 inch (0.762 mm.) thick steel. Similarly, top sheet 36 is a flat, rigid sheet type member formed of about 0.035 inch (0.889 mm.) thick steel. The top sheet 36 includes a top surface that may be finished in any of several different ways depending upon the application that configuration 10 is to be used for. For instance, the top surface of sheet 36 may be painted, a laminate or veneer may be glued thereto, a thin film material may be applied, a spray ceramic coating may be sprayed on and then baked to cure, etc. Such a top surface treatment is shown as top surface layer 37 in
Core matrix 14, as the label implies, includes a matrix-type configuration. Core matrix 14, in at least some of the embodiments, is formed of flat sheet steel approximately 0.027 inch (0.686 mm.) thick, that is formed via a cutting and pressing process into the illustrated matrix structure.
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Referring now to FIGS. 2 to 8, core matrix 14 includes a first group of spaced top coplanar lands 16 defining a first bearing surface of core matrix 14, and a second group of spaced bottom coplanar lands 19 defining a second bearing surface of core matrix 14. The first bearing surface and the second bearing surface are arranged in parallel spaced apart relationship. In one exemplary embodiment of core matrix 14, bottom lands 19 are ½ inch (12.7 mm.) or less in diameter, top lands 16 are about 1 inch (25.4 mm.) in diameter, and there is about 2 inches (50.8 mm.) between each two adjacent top lands and about 2 inches between each two adjacent bottom lands. Here, top lands 16 have a larger surface area than the bottom lands 19 to provide a larger surface area suitable for adhesive bonding as opposed to weld-type bonding.
While weld-type bonding generally provides a superior bond, it has been recognized that welding can result in irregularities in surface appearance and texture. For this reason, while welding may be suitable in some applications where associated surfaces are not easily or intended to be observable, in other applications where an associated surface is observable, welding may not be suitable. Thus, in the present application where a top surface of top sheet 36 is often observable, adhesive attachment of sheet 36 to matrix 14 and hence relatively larger lands are often optimal.
Core matrix 14 includes a bridging structure 22 that connects the first group of spaced coplanar top lands 16 and the second group of spaced coplanar bottom lands 19. The bridging structure 22 has throughholes 25 arranged around each top land 16. Referring to FIGS. 2 to 4, the throughholes 25 are arranged “in line” between top lands 16 and adjacent bottom lands 19. Here, “in line” means that traveling down the surface of bridging structure 22 between one of the top lands 16 directly toward an adjacent bottom land 19, the line of travel passes through one of the throughholes 25.
The throughholes 25 are provided as illustrated to provide strain relief to core matrix 14 during the pressing formation process. Thus, it has been recognized that most strain on the core matrix 14 during formation occurs where throughholes 25 are formed. By removing the core matrix material at the throughhole locations prior to forming, material rips and tears are avoided or at least appreciably reduced.
Referring to
In the exemplary embodiment of core matrix 14, top lands 16 are circular and bottom lands 19 are circular, although other shapes are contemplated. Throughholes 25 are oval or elliptical, although other shapes are contemplated. In
In one version of the worksurface configuration 10, core matrix 14 is spot welded to bottom sheet 42 and adhesively bonded to top sheet 36. However, the invention is not limited to these attachment methods for core matrix 14, bottom sheet 42 and top sheet 36. For example, top sheet 36 may be welded to the core matrix 14 if damage to top surface layer 37 and top sheet 36 can be avoided. It should be appreciated that adhesively bonding core matrix 14 and top sheet 36 (including top surface layer 37) allows for efficient and flexible finish options without danger of damaging top surface layer 37. Relatively low, short duration heat is required (e.g., 220° F. for 6 seconds) to cure at least some types of adhesives. Most worksurface finishes will not be damaged by heating of this magnitude and duration.
Turning now to FIGS. 9 to 12, there is shown an edge configuration 56 for the perimeter of a worksurface configuration 10 according to at least some inventive embodiments. Edge configuration 56 includes an edge channel 58 and an edge member 74. Edge configuration 56 is mounted in a perimeter area 21 (see
Edge channel 58 shown in FIGS. 9 to 12 includes a back wall 59 having top or first and bottom or second edges 60 and 61, respectively, a first group of spaced apart upper tabs 64 extending outwardly from top edge 60 in a first direction, and a second group of spaced apart lower tabs 69 extending outwardly from bottom edge 61 in the first direction such that tabs 64 and 69 are substantially parallel.
Each of upper tabs 64 is similar in configuration and operation and therefore only one of the tabs 64 will be described here in detail. To this end, referring still to
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In at least some embodiments, the wide edge 150 of each upper and lower tab is approximately ½ inch although other widths are contemplated. In addition, channels 58 are contemplated where the wide edge widths 150 may vary along the length of the channel depending upon functional requirements associated with an application.
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Next, fingers 76 and 78 are aligned with upper and lower channels 67 and 72 and then are pressed into channels 67 and 72. While fingers 76 and 78 are pressed into channels 67 and 72, barbs 66 and 71 penetrate surfaces 81 of fingers 76 and 78 and hence hold edge member in position along the edge of the worksurface configuration (see
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The spacer 84 is dimensioned to fit in the interior space 40 (see
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When mounting a leg 91 to the worksurface configuration 10, holes 93 of mounting bracket 92 are aligned with holes 88 in the spacer. A fastener (preferably a screw) is inserted through each hole 93 of the mounting bracket 92 and through the bottom sheet 42, and each fastener engages a hole 88 in one of the flanges 87a, 87b, 87c and 87d of the spacer 84.
Having described the components of worksurface configuration 10, an example sequence of forming construction operations can now be described. It should be appreciated that variations on the sequence are also possible and are contemplated.
Core matrix 14 may be formed by first forming a flat blank of planar sheet metal in the shape of a desired worksurface. Next, throughholes 25 are punched or laser cut in the blank sheet at equispaced locations along columns and rows. For instance, throughholes 25 may be spaced approximately two inches on center such that the centers of each group of four adjacent throughholes 25 form a square having a central section located between each group of four throughholes 25 and bridge regions located between adjacent central sections. During deformation, the central sections are pressed to form top lands at one side of core matrix 14 and bottom lands 19 at an opposite side of core matrix 14.
More specifically, where the central sections form columns and rows, the central sections in every other column and in every other row are used to form top lands 16 and the central sections between four of the central sections that form top lands 16 are used to form bottom lands 19. To form the core matrix 14 from the blank, a press is used that includes oppositely facing pins where a first set of pins is arranged to align with the central sections of the blank that are to form the top lands 16 and a second set of pins is arranged to align with the central sections of the blank that are to from the bottom lands 19. Next, the blank is aligned with the press pins and the press is activated to form core matrix 14.
In at least one version of the method, the blank is deformed such that a top plan view of the flat blank has the same perimeter dimensions as a top plan view of core matrix 14. It has been recognized that throughholes 25 can be formed at the locations where the greatest amount of stretching occurs during pressing which allow additional stretching to occur without tears or rips and so that the number of alternating top lands 16 and bottom lands 19 can be maximized without requiring a drawing die type process.
After forming core matrix 14, edge channel 58 is welded to an interior surface 44 of bottom sheet 42.
The formed core matrix 14 is then placed on surface 44 of bottom sheet 42 within the space defined by channel 58. If desired, reinforcement brackets 50, including a top flange 51 and a bottom flange 52 may be placed on bottom sheet 42 as in
The assembly is then placed in a spot welding machine and core matrix 14 is spot welded to bottom sheet 42 at every touch point (i.e., at the location of every bottom land 19). An automated welder may be programmed to recognize the presence of a touch point and make welds. In an exemplary operation, the spot welds used to secure bottom lands 19 to bottom sheet 42 are about an ⅛ inch (3.175 mm.) in diameter. In some cases, laser welding instead of high heat spot welding is used to weld core matrix 14 to bottom sheet 42 to avoid curling and other heat related deformations of core matrix 14. Where laser welding is performed, it is important to have a flat portion between bottom sheet 42 and core matrix 14 so that more than a point weld can be formed. Thus, in the most preferred embodiment, bottom lands 19 include a small flat circular surface so that a circular weld can be formed. Bottom sheet 42 of the assembly may then be powder coated, laminated or other otherwise finished.
Top sheet 36 is finished by, for example, gluing a laminate, powder coating or ceramic coating. In one exemplary embodiment, top sheet 36 may be covered with a spray on ceramic coating that is baked to cure after spraying. Here, ceramic coating is highly durable and the end product is environmentally friendly as the ceramic and steel are both recyclable. In at least some embodiments, top surface layer 37 and all edges of top sheet 36 are coated with the ceramic material. The ceramic may be selected such that the top surface layer 37 is akin to a whiteboard surface so that persons using a desk or the like that includes the surface can write and erase thereon. One suitable ceramic material for some applications is a porcelain enamel.
A number of spacers 84 (typically equal to the number of legs 91) are then secured to the bottom sheet 42 of the assembly where legs 91 are to be mounted. Adhesive is placed on all high points of the bottom assembly (i.e., top lands 16, upper tabs 64 of edge channel 58, top wall 85 of spacers 84, and top flanges 51 of any reinforcement brackets 50). The finished top sheet 36 is positioned on the bottom assembly and pressed in place and the adhesive is cured (e.g., by conduction, radiation or induction).
Edge member 74 is next installed in edge channel 58 around the perimeter of worksurface configuration 10. Edge member 74 is moved toward edge channel 58 such that first mounting finger 76 of edge member 74 enters upper channel 67 and second mounting finger 78 enters lower channel 72. Barbs 66 and 71 penetrate outer surfaces 81 of fingers 76 and 78 and securely hold edge member 74 in place in edge channel 58.
Legs 91 are next mounted to worksurface configuration 10. The holes 93 of the mounting bracket 92 are aligned with the holes 88 in the spacer 84. A fastener (preferably a screw) is inserted through each hole 93 of the mounting bracket 92 and through the bottom sheet 42, and each fastener engages a hole 88 in one of the flanges 87a, 87b, 87c and 87d of the spacer 84.
Worksurface configuration 10 has many advantages. The shape and design of core matrix 14 provides for an efficient blank and forming operation that does not require significant tonnage and does not change the overall plan view shape of the blank. It also provides for frequent connection to top sheet 36 and bottom sheet 42 minimizing local weaknesses in the worksurface top. Also, the shape of core matrix 14 provides high strength through the double saddle form effectively connecting each attachment location (i.e. top lands 16 and bottom lands 19).
Throughholes 25 formed between top lands 16 and bottom lands 19 are also important. In this regard, in order to maintain structural integrity of worksurface configuration 10 including all three layers (i.e., top sheet 36, core matrix 14 and bottom sheet 42), the number of lands (top and bottom) formed in core matrix 14 has to be maximized (large numbers of lands provide support even along arcuate edges and can be used to support less rigid external sheets). To provide large numbers of lands, a large amount of blank sheet stretching is required. When sheet metal is locally overstretched, the metal has a tendency to tear which is unacceptable in the present application. The specifically placed throughholes 25 in core matrix 14 enable a flat stock sheet of metal to be forced into the waffle or matrix shape via stretching without causing tears to the sheet material. Also, when throughholes 25 are specifically placed in the core matrix 14, when the sheet is stretched to form the waffle shape, the overall area of the sheet in plan view remains essentially unchanged (i.e., a 4 by 4 foot sheet will remain essentially 4 by 4 foot after waffling). More specifically, in the present invention, throughholes 25 are formed between top lands 16 and bottom lands 19 where the greatest amount of stretching is anticipated. Thus, the holes in the sheet advantageously allow large numbers of lands to be formed via a cold press process and also allow a manufacturer to produce known size and shape waffle members without any guess work.
Thus, there has been provided a worksurface configuration that is lightweight, thin, extremely stiff and rigid, workable into many different shapes and sizes, is easy to manufacture and that can be finished in variable ways. In addition, there has been provided an edge trim configuration suitable for use with a waffle assembly type member, and a suitable way to mount legs or other support structure to the underside of a waffle assembly type structure. Also, there has been provided a method that facilitates configuration of multiple work surface types having the aforementioned characteristics.
While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed.
For instance, while it may be optimal in some applications to weld the matrix core 14 to a lower sheet and adhere the top sheet to the core 14, in other applications both the top and bottom sheets may be adhered to or welded to the core matrix 14. In addition, in some cases other mechanical attachment means such as rivets, etc., may be used to secure the bottom sheet to the core. In another instance, while the top and bottom sheets are described as being formed of steel, other metals may be used or, indeed other types of rigid sheet including fiberglass, graphite, laminates, etc.
In addition, while each of the 3-layer worksurface sub-assembly, edge sub-assembly and leg mounting sub-assembly may be employed together, it should be appreciated that each of the assemblies has advantages alone or in conjunction with other sub-assemblies.
Moreover, while one matrix core design 14 has been described above, other designs are contemplated. For instance, instead of providing four throughholes 25 around each upper land 16 and in-line between each upper land 16 and adjacent lower lands 19, three throughholes 25 may be equi-spaced about each upper land and there may only be three lower lands equi-spaced about each upper land where each of the throughholes 25 is located in-line between the upper and an adjacent lower land. As another instance, five, two or other numbers of holes may be equi-spaced about each upper land or, in some cases, the throughholes may be other than equi-spaced.
Furthermore, in at least some cases the throughholes may be spaced from top lands and/or may “touch” bottom lands.
In addition, while the assembly illustrated in
Thus, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims. To apprise the public of the scope of this invention, the following claims are made.
