Patent Grant
8640911
This invention relates generally to a modular case and method of forming the same, and more particularly to a modular plastic case made from dual-skinned plastic panels with internal ribs, joined by various corner and connecting members with internal ribs, such that the internal ribs are aligned, allowing for a modular case enjoying superior structural qualities, such as strength, structural integrity, and stiffness, that can be cost-effectively produced in any desired size.
In the past, cases for shipping and other applications have been fabricated from plywood panels (with or without plastic skins bonded to the surfaces) joined by attachment to metal edge members (usually by rivets). Such cases could be provided with handles and other attachments by cutting holes in the plywood panels, inserting the desired attachment and riveting the attachment in place.
Such cases were very susceptible to various types of damage when dropped, handled roughly, or generally subjected to localized impacts. The metal edge members were easily bent, the riveted attachments were easily broken or sheared, the holes cut for the attachments could become elongated, and the plywood panels were subject to splintering and delaminating.
Additionally, the cases made from plywood panels were particularly unsuitable for applications requiring an airtight or watertight case. Some air- and water-tightness could be achieved using sealants and gaskets, but the application of such sealants and gaskets was time-consuming and costly. Moreover, with rough handling, an air- or water-tight seal was difficult to maintain.
As cases, generally, and shipping cases particularly, are likely to experience rough handling and localized impacts, it is clear that a case with superior structural qualities is needed. Cases made from molded plastic (injection molding, rotational molding, thermoforming, blow molding, etc.) exhibited some of the desired structural qualities, but did not enjoy the design flexibility of the plywood panel cases.
That is, the plywood panel and metal edge members could be easily cut and sized for a wide range of required case sizes. To produce differently sized molded plastic cases with the desired structural qualities, however, would typically require a new dedicated mold for each separately dimensioned case. Thus a differently sized molded plastic case was expensive and time-consuming to produce. As a result, the design flexibility of the molded plastic cases was limited compared to the plywood panel cases.
With the foregoing problems and concerns in mind, the general object of the present invention is to provide a modular case, most preferably a plastic case, that enjoys superior structural qualities while matching or exceeding the design flexibility of plywood panel cases.
It is an object of the present invention to provide a modular case made from hot-plate welded plastic panels and plastic edge members.
It is a further object of the present invention to provide a modular case, wherein the plastic panels have ribs, the plastic panels being formed from inner and outer panel halves, each panel half having integral rib surfaces, the panel being formed by the two panel halves being hot-plate welded together on opposing integral rib surfaces.
It is a further object of the present invention to provide a fabricated plastic case wherein the panels and edge members have uniformly spaced ribs, and the panels and edge members are cut and connected such that ribs meeting at joints are joined end to end, providing a plurality of substantially integral ribs capable of effectively distributing forces about the modular case structure.
It is a further object of the present invention to provide a modular case with edge members that include molded protuberances and/or recesses for advantageous engagement between a lid and a base, or between two or more cases.
It is a further object of the present invention to take advantage of the inner and outer skin construction of the modular case panels and edge members, to provide mounting holes and inserts that allow a wide variety of attachments to be secured to the case while maximizing the strength and structural integrity of the case.
It is a further object of the present invention to provide separately pre-fabricated panels and edge members that can be separately cut-to-size to accommodate the manufacture of differently sized modular cases.
It is a further object of the present invention to provide panels and edge members that once joined become integral of one another, and provide a modular case that has greater impact resistance and water-tightness than known modular container systems.
These and other advantages of the present invention will be better understood in view of the Figures and preferred embodiment described.
Typically, cases do not require deep lids. In the event a deeper lid is required, a deeper lid (not shown) is formed incorporating the vertical side panels 22 as in the base 20, except that a modified lid parting line capable of connecting to the bottoms of the lid vertical side panels (not shown) is used. Additionally, where a double-entry case (not shown) is required (e.g. for containing rack-mounted electronics), two lids 40 are used together with a midsection (not shown). The midsection is formed like the base 20, except no bottom panel and base horizontal edge members are used, and the resulting open area is surrounded by a second base parting line, such that the midsection is open on two ends, each end provided with a parting line for receiving a lid.
Panels, edge members, and corner pieces are preferably pre-fabricated stock. To create a case of desired dimensions X, Y, and Z, the top and bottom panels 22, base horizontal edge members 24, base parting line edge members 28, and lid parting line edge members 42 are cut from the pre-fabricated stock (master panels and edge members) to correspond to the desired X and Y dimensions. The first two side panels 22 are cut to correspond to the desired Y and Z dimensions and the second two side panels 22 are cut to correspond to the desired X and Z dimensions. The base vertical edge members are cut to correspond to the desired Z dimension. In precisely sizing the case in a given dimension, it is necessary to consider the thickness of the edge members in that direction. For example, the total height of the case in the Z dimension includes not only the height of panel 22 in the Z dimension, but also the combined thicknesses of the base horizontal edge member 24, base parting line edge member 28 and lid parting line member in the Z dimension. As a given edge member is preferably cut only to correspond to a single dimension (e.g. the base horizontal edge members are only cut to correspond to the X or the Y dimension), proper overall dimensioning requires proper sizing of the panels 22 to accommodate for the added width of the edge members.
The cut panels and edge members, together with the corner pieces, are then joined (the manner in which the joints are preferably formed is discussed in more detail below) to form the case 10. Preferably, all joints are hot plate welded, which provides a strong and air-/water-tight seal along the length of the weld. The lid 40 is typically not welded to the base 20, but removable to facilitate loading/unloading of the case 10 (various features of the parting line are discussed in more detail below). The order in which the modular components are cut and joined is not critical, but can be varied as required given assembly conditions.
From the foregoing, it can be appreciated that the present invention provides a case, especially a plastic case, that can easily be formed to any desired size by cutting modular elements from pre-fabricated stock (the master panels and edge members) and joining the elements together. In contrast to known plywood cases, and methods of making the same, it can be seen that the present invention provides panels, edge members, and corner pieces which become integral once hot-plate welded, enhancing strength and air-/water-tight integrity.
Turning to the perspective view of the panel 22 shown in
Internal features of the panel 22 are shown in
The base horizontal edge member 24 will now be described, referring to
The intersections 250 are preferably formed as bosses 250 with the areas of the inner skin 242 covering the centers of the bosses 250 removed to form a plurality of integral mounting holes 252 in the base horizontal edge member 24. Since the outer skin 240 is not penetrated, the mounting holes 252 do not affect the air- or water-tight integrity of the case 10, while allowing the attachment of accessories including mounting frames, racks, decks, and shock mounts. If more secure attachment of accessories is required, a hole is drilled through the outer skin 240 allowing a bolt or other fastener to be inserted through a mounting hole 252, in which case a sealant may be used to maintain air- or water-tight integrity of the case 10. The outer skin 240 is preferably formed with a flat surface 254 on a portion covering the bosses 250 to provide a space for washers, bolt heads, or other fastener surfaces.
The above demonstrates another advantageous aspect of the present invention. Unlike in conventional plywood cases, the edge members are formed as dual skinned members with internal ribs. The edge members formed in this fashion are correspondingly lighter, more air-/water-tight, and more impact resistant, thus out-performing the more conventional metal or other solid edging.
Turning to
The base vertical edge member 26 is most preferably formed with an integral corner piece 276. Alternatively, a separate corner piece could be provided or a corner piece could be integral to the base horizontal edge members 24. When the base vertical edge member 26 is connected between two panels 22, the integral corner piece 276 extends below the connection and is adapted for connection between two base horizontal edge members 24.
The advantageous alignment of the ribs in the panels 22 and edge members 24 and 26 will now be explained.
When the panels 22 and edge members 24, 26 are cut from stock to fabricate a case 10 of desired dimensions, the cuts are preferably made so that the ribs 222 and angled ribs 244, 264 terminating at the joints 70 will align end to end. When the connections are made, preferably by hot-plate welding, substantially integral ribs will be formed through the sides and around the edges and corners of the case 10. For example, the rib 700 and a rib 704 terminate at the joints 70a and 70b, respectively. The angled rib 702 terminates at both the joints 70a and 70b. The joint 70a is made such that an end of the rib 700 is joined to the end of angled rib 702. The joint 70b is made such that an end of the rib 704 is joined to another end of the angled rib 702. Joined in this manner, the rib 700, angled rib 702 and rib 704 form an integral rib through the joints 70a and 70b. Similarly, the rib 706, an angled rib 708, and a rib 710 form an integral rib through the joints 70c and 70d, and a rib 712, an angled rib 714, and a rib 716 form an integral rib through the joints 70e and 70f. The intermediate ribs 246, 266 are not joined to the panel ribs 222, but provide an edge member structure that is less susceptible to damage and abuse.
Yet another important advantage of the present invention is shown in this ability to transmit forces not only throughout the panels, but also throughout the edge members and the entire structure of the case. The alignment the plurality of ribs throughout the case provide greatly enhanced strength and toughness in a light and more air-/water-tight case.
By using the panels 22 and edge members 24, 26 with inner and outer skins, the connection area of the joint 70 is maximized. Preferably, the spacing between the panel outer skin 220 and inner skin 222 is equal to the spacing between the edge member outer skin 240, 260 and inner skin 242, 262. When a connection is made at the joint 70, then not only are the rib ends aligned, but also the edges of corresponding inner and outer skins lying along the joint 70. When the connection is made using hot-plate welding, the total weld area includes both the rib ends and also the corresponding edges of the inner and outer skins. The use of dual-skinned panels and edge members joined with the corresponding edges of the inner and outer skins aligned also provides a case with a smooth, seamless interior, which is useful for many applications.
As discussed above, the integral corner 276 of the base vertical edge member 26 is adapted for connection with the base horizontal edge members 24. The geometry of such a connection can be seen in
From the foregoing it can be seen how the present invention provides a modular case with substantially integral ribs. Localized forces acting on the case 10 can thus be effectively distributed via the integral ribs throughout the structure of the case 10, resulting in an extremely strong and impact resistant case. Integrating the rib structure through edges and corners allows the case added strength at these particularly impact-susceptible locations. The dual-skin structure with internal ribs offers greater impact resistance and air-/water-tightness than known plywood cases, while also weighing substantially less than heavy-duty plywood cases engineered to provide similar attributes.
Turning now to
The upper ends of outer skin 280 and inner skin 282 are connected by a parting line surface 290. The parting line surface 290 extends beyond the recessed upper portion of the outer skin 280 to partially overhang the recesses 288. A plurality of protuberances, preferably tabs 292, are formed on the portion of the parting line surface 290 overhanging the recesses 288. Toward an inner side of the parting line surface 290 an extended longitudinal ridge, or gasket penetrator 294, is preferably provided, spaced apart from and running parallel to the tabs 292. The tabs 292 and gasket penetrator 294 are adapted for advantageous engagement with corresponding features of the lid parting line edge member 42, as will be described below. Additionally, it is preferred that the base parting line edge member be formed to include a plurality of sockets 296. The sockets 296 are preferably formed as bosses extending between the outer skin 280 and the inner skin 282, accessible through openings formed in the inner skin 282. The sockets 296 are preferably arranged in socket pairs and adapted to allow for the advantageous mounting of hardware, as will be explained in detail, below.
The base parting line corner pieces 30, shown in various views in
The structure of the lid 40 will now be discussed. The panel 22 forming the top of the lid 40 is preferably formed identically to the panels 22 that form the sides and bottom of the base 20.
The outer skin 420 is recessed on a vertical portion of the lid parting line edge member 42 such that the ribs 424 protrude beyond the outer skin 420 on the vertical portion forming a plurality of recesses 428 that correspond to the recesses 288 on the base parting line edge member 28. The lid parting line edge member 42 is preferably provided with a plurality of protuberances 429 formed on the outer skin 420, and with a plurality of sockets 436 arranged along the longitudinal rib 427. The sockets 436 are preferably formed as bosses extending inward from the outer skin 420, and arranged as socket pairs. The parting surface 430 preferably includes a plurality of parting surface recesses 432 adapted to accommodate the tabs 292 of the base parting line surface 290. Spaced apart from the recesses 432 on parting line surface 430 is a continuous groove, preferably gasket groove 434. The groove 434 and the gasket penetrator 294 cooperate as described below.
The lid parting line corner pieces 44, shown in various views in
The groove 434 (which extends continuously along the lid parting line) is adapted to receive a compressible gasket (not shown). When the lid 40 and base 20 are held together, the gasket penetrator 294 compresses the gasket in the groove 434 along the entire perimeter of the parting line, establishing an air-/water-tight seal.
The advantageous cooperation between the protuberances 256 on the base horizontal edge member 24 and the protuberances 429 on the lid parting line edge member 42 will now be explained, referring to
From the foregoing it can be seen how the molded protuberances and/or recesses on the base horizontal edge members 24, base parting line edge members 28, and lid parting line edge members 42 provided on the modular case 10 allow for advantageous engagement of the opposing top and bottom surfaces of two or more stacked cases, and of the opposing parting line surfaces on a given case.
The attachment of the handle assemblies 800 can be most easily seen in
The handle assembly 800 is accommodated in the panel 22 by removing a portion of the outer skin 220 and the ribs 224 to form a handle recess 808 corresponding to the dimensions of the mounting well 804. The inner skin 222 is preferably left intact. When the mounting well 804 is inserted in the handle recess 808, the mounting flange 806 abuts the outer skin 220 around the handle recess 804. The handle assembly is secured to the case 10 by screws or other fasteners inserted through the mounting holes 807 and a plurality of holes 810 in the area of the outer skin 220 abutted by the mounting flange 806, but preferably not through the inner skin 222. Preferably, the handle assembly 800 is positioned such that the mounting holes 807 and holes 810 are aligned with bosses 230 (see
The attachment of the catch assemblies 900 can most easily be seen referring to
The area of the parting line surface 290 overhanging the recess 288 and the corresponding area of the parting line surface 430 are preferably removed to allow the catch 902 and catch strike 904 to lie in the same plane. Air- and/or water-tight integrity is not affected by this partial removal of parting line surfaces as the gasket groove 434 and penetrator 294 are completely intact. The holes 908 are preferably made in the outer skins 420 and 280 to correspond to pairs of sockets 436 and 296, such that each rivet 906 extends into a corresponding socket 436 or 296 through a hole 908.
A plurality of mounting inserts 910 (seen enlarged in
The holes 908 in the outer skin 420 and 280 are sized to tightly accommodate the mounting insert noses 922 when a mounting insert 910 is inserted into a socket 436 or 296. When so inserted, o-ring 919 sealingly engages the walls of the socket 436 or 296, preventing communication through the holes 908 into the interior of the case 10. When a catch assembly 900 is secured by a rivet 906, the rivet 906 enters the bore 922 (the expansion space 918 allows for the body 912 to expand when accommodating a rivet 906) such that forces acting on the rivet 906 are not directly transmitted to the walls of the hole 908 but instead are distributed over a larger area.
From the foregoing it can be seen how features of the present invention, such as dual skinned panels and edge members, sockets, bosses, and mounting inserts allow for the secure attachment of hardware while preserving the air-/water-tight integrity of the case 10. Forces acting on hardware so attached are effectively distributed over larger areas than in conventional cases, minimizing the likelihood of hardware detachment, elongated rivet holes, and related problems.
While many advantages of the present invention can be clearly seen from the preferred embodiment described, it will be understood that the present invention is not limited to such an embodiment. Those skilled in the art will appreciate that many alterations and variations are possible within the scope of the present invention.
Additionally, panel designs other than the dual skinned panel 22 may be advantageously employed within the scope of the present invention. For example, while the dual-skinned panel 22 provides exceptional durability and allows for high air- and/or water-tight integrity, even when various attachments are secured to the case 10, in applications where a lighter case is desired, or where air- and/or water-tight integrity is not as critical a design factor, panels designs may be employed to retain many of the advantages of the dual-panel design with a substantial weight reduction.
Referring to
In
A panel 1422, as seen in
The panels of
While many advantages of the present invention can be clearly seen from the embodiments described, it will be understood that the present invention is not limited to such embodiments. Those skilled in the art will appreciate that many alterations and variations are possible within the scope of the present invention.
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