Load bearing structure
11603233 · 2023-03-14
Assignee
Inventors
Cpc classification
B65D2519/00333
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00437
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00293
PERFORMING OPERATIONS; TRANSPORTING
B65D19/18
PERFORMING OPERATIONS; TRANSPORTING
B65D19/0002
PERFORMING OPERATIONS; TRANSPORTING
B65D19/0026
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00273
PERFORMING OPERATIONS; TRANSPORTING
B65D19/0018
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00825
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00562
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00587
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00805
PERFORMING OPERATIONS; TRANSPORTING
B65D19/40
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00502
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00407
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00343
PERFORMING OPERATIONS; TRANSPORTING
B65D19/0012
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00338
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00641
PERFORMING OPERATIONS; TRANSPORTING
B65D2519/00497
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
The present invention provides a thinner, movable load bearing structure having indentations, grooves, valleys, channels or other similar depressions on its underside. These depressions are mated with corresponding features for improved loading bearing capabilities. The load bearing structures also includes roughened side edges for improving the strength of the edges. The load bearing structure may be a dunnage platform or a container for storing and/or shipping cargo.
Claims
1. A load bearing structure for loading, transporting or storing cargo, comprising: an expanded polymeric core having a top side with outer edges, a bottom side with outer edges and a width having a thickness therebetween joining the top side and the bottom side of said core; at least one polymeric sheet having a first side with outer edges are combined with said expanded polymeric core on said bottom side and at least a portion of the thickness of the width of said expanded polymeric core to form a load bearing structure with outer edges; a plurality of supports extending orthogonally from the bottom side of the core and spaced away from the edge of the core; and at least one feature present along a portion of at least one of said outer edges of said core, said feature comprising portions of roughened edges for decreasing the total weight and for increasing the strength of said outer edges of said load bearing structure; wherein said roughened edges of said core retain their shape after combining with said at least one polymeric sheet to form the load bearing structure.
2. The load bearing structure of claim 1 wherein said roughened edges are saw-tooth edges.
3. The load bearing structure of claim 2 wherein each tooth of said saw-tooth edges comprises a length that is substantially the thickness of the width of the outer edge, substantially half the thickness of the width of the edge, or the length of each tooth maybe of any length in between one half and full length.
4. The load bearing structure of claim 1, further comprising at least one depression on the bottom side of the polymeric core, extending substantially the length or breadth of said bottom surface.
5. The load bearing structure of claim 4 further comprising a corresponding feature mated with at least one of said depressions to substantially fill said depression, said feature having a raised portion.
6. The load bearing structure of claim 1, wherein said portions of roughened edges is present along at least two parallel sides of the core.
7. The load bearing structure of claim 1 further comprising unroughened outer edge portions, wherein said portions of roughened edges do not protrude further from the outer edges of the core than the unroughened outer edge portions.
8. The load bearing structure of claim 1 further comprising unroughened outer edge portions, wherein said portions of roughened edges extend for a certain length along the outer edge of the core, interrupted occasionally by unroughened edge portions.
9. A loading bearing structure comprising: a polymeric core having a top side with outer edges, a bottom side with outer edges, and a width having a thickness therebetween joining the top side and the bottom side, at least a portion of one of said outer edges comprising portions of roughened edges for increasing the strength of said outer edges of said load bearing structure; a plurality of supports extending orthogonally from the bottom side of the core and spaced away from the edge of the core; and at least one polymeric sheet having a first side with outer edges, said first side of said polymeric sheet including the outer edges are combined with said bottom side, said plurality of supports, the width and at least a portion of said top side of said polymeric core; wherein said portions of roughed edges are disposed on said outer edges of said core are interrupted occasionally by unroughened edge portions of the load bearing structure.
10. The load bearing structure of claim 9 wherein said roughened edges comprise a plurality of teeth having various lengths and shapes.
11. The load bearing structure of claim 10 wherein the ends of the teeth are substantially smooth, flat or slightly pointed.
12. The load bearing structure of claim 10, further comprising at least one bridge spanning between adjacent supports.
13. The load bearing structure of claim 12 further comprising at least one depression on the bottom side of the polymeric core, extending substantially the length or breadth of said bottom surface.
14. The load bearing structure of claim 13 further comprising a corresponding feature mated with said at least one depression, said feature having a raised portion.
15. The load bearing structure of claim 14 further comprising a second polymeric sheet having a first side and a second side, with outer edge portions, said second side and its outer edge portions are combined with said expanded polymer core on said top side and at least part of the width of said expanded polymer core, wherein said outer edge portions of said first sheet overlaps said outer edge portions of said second sheet about the width.
16. The load bearing structure of claim 15 wherein said structure supports at least fifteen times its own weight for up to one week with an average deflection of less than 2%.
17. A load bearing structure for loading, transporting or storing cargo, comprising: an expanded polymeric core having a top side with outer edges, a bottom side with outer edges, and a width having a thickness therebetween joining the top side and the bottom side about the edges; a plurality of supports extending orthogonally from the bottom side of the core and spaced away from the edge of the core; at least one polymeric sheet having a first side with outer edges are combined with said expanded polymer core on said bottom side, and at least a portion of the thickness of the width of said expanded polymeric core, respectively; at least one feature for decreasing the total weight of the load bearing structure and increasing the strength of at least one of said edges of the load bearing structure, said feature comprising portions of roughened edges.
18. The load bearing structure of claim 15 wherein said portions of roughened edges extend for a certain length along the outer edge of the core, interrupted occasionally by unroughened edge portions.
19. The load bearing structure of claim 15 wherein said roughened edges are integral to the polymeric core and retain their shape after combining with said polymeric sheet.
20. The load bearing structure of claim 15 wherein said polymeric core has a thickness of between about 120 mm and 130 mm.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE INVENTION
(52) The detailed description set forth below is intended as a description of the presently exemplified systems, devices and methods provided in accordance with aspects of the present invention and are not intended to represent the only forms in which the present invention may be prepared or utilized. It is to be understood, rather, that the same or equivalent functions and components may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention belongs. Although any methods, devices and materials similar or equivalent to those described herein can be used in the practice or testing of the invention, the exemplary methods, devices and materials are now described. All publications mentioned herein are incorporated herein by reference for the purpose of describing and disclosing, for example, the designs and methodologies that are described in the publications which might be used in connection with the presently described invention. The publications listed or discussed above, below and throughout the text are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the inventors are not entitled to antedate such disclosure by virtue of prior invention.
(53) Load bearing structures that are strong and light weight may be useful for transporting cargo by air, land or sea. For transportation by air, the financial benefits of a light weight load bearing structure is greater than other modes of transportation, even though the benefits from a light weight load bearing structure may be felt by all modes of transporting cargo.
(54) The present invention relates to a strong, light weight load bearing structure including a light weight polymeric core covered by or combined with one or more polymeric sheets or films. The light weight polymeric core may be made of closed cell foams including polystyrene foam, polyurethane foam, vinyl, acrylic or phenolic foam, as noted above. The density of the foam, as noted above, may range from about 15 kgs per cubic meter to about 45 kgs/cubic meter, more for example, 20 kg/cubic meter to about 35 kg/cubic meter, even more for example, between about 21 kg/cubic meter to about 30 kg/cubic meter, and still more for example, between about 23 kg/cubic meter about 25 kg/cubic meter. As noted above, no matter the density of the foam, it does not substantially contribute to the overall strength of the load bearing structure, though it may affect the strength to a degree. For a higher density foam, the polymeric core may have a smaller thickness. However, as also mentioned above, with limited space in air cargo transport and the desire to have lighter weight load bearing structures to save cost in transport, higher density foam that contributes to the higher overall weight may not be as desirable. Thus, for air cargo transport, the thinner and lighter weight the core, the more suited is the load bearing structure. For example, the more desirable thicknesses of the core suited for air cargo may vary from about 120 mm to about 130 mm. At these thicknesses without substantially higher density core, the load bearing capabilities as mentioned above by the deformation test, may suffer.
(55) To improve the load bearing capabilities, such as the capability to transport more weight, without making the load bearing structure heavier, the core may include at least one groove, valley, indentation or channel on the underside and at least one corresponding feature matted with one of the at least one groove, valley, indentation or channel. The grooves, valleys, indentations or channels may be of any shape, for example, substantially half-moon shape or square sides. The corresponding feature may also be of any shape and may include a central portion having a cross-section of any shape, for example, a substantially dome-like cross-section, a substantially trapezoidal cross-section, a substantially triangular cross-section, a substantially rectangular cross-section, or others, with or without wing-like features extending from both sides of the lower portion of the central portion. The central portion may substantially fill in one of the at least one grooves, valleys, indentations or channels. The wing-like features, if present, may have a small thickness such that when the feature is combined with the load bearing structure, the feature may be substantially flushed with the rest of the underside of the load bearings structure to present a relatively smooth feel with very little visible protrusion or bump. The load bearing structure having at least one groove, valley, indentation or channel on the underside of the polymeric core, and with the at least one groove, valley, indentation or channel combined or covered with the at least one feature has improved properties, such as the capability to transport more weight than a load bearing structure without grooves, valleys, indentations or channels.
(56) In
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(58) The load bearing structure 10 also has a width 12 having a thickness 14, which is the combined total thickness of the core 10a and sheet 67, mentioned above. Cargo may be loaded on the top side 16a of the load bearing structure 10. The cargo may be perishable or non-perishable and may include food such as fresh vegetables and fruits, poultry and meat products, pharmaceuticals and drugs, electronic components and devices, etc.
(59) In some exemplary embodiments, the polymeric core may include at least one groove, valley, channel, indentation and/or other recess, as shown with grooves, valleys, channels, indentations and/or other recesses 13, 13′, 15, 15′, 15″ in
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(61) In some embodiments, the grooves may extend in only one direction on the polymeric core, as shown with a first direction in
(62) For another example, the feature or member 17 may be, for example, adhered, combined, or fused to the polymeric sheet, layer or film if the polymeric core has been covered or bonded with the polymeric film, layer or sheet. The members or features 17 may generally conform to the surface of the polymeric core, if the features or members are present prior to the covering of the core with the sheet, film or layer, or the surface of the load bearing structure, if the features or members are present after the core has been covered or bonded to the polymeric film, sheet or layer.
(63) In one embodiment, the feature or member may also include wing-like features, for example 17a as shown in
(64) The wing-like features 17a may be of uniform thicknesses or they may be tapered towards the ends to further conform to the surface of the core, if the feature or member 17 is present prior to covering or combining the core with sheet or film, or the sheet or conform to the surface of the loading bearing structure, if present after covering or combining the core with sheet or film.
(65) The feature or member 17 may also take on a polygonal form, such as illustrated with the features 17 in
(66) In some embodiments, the supports may feature at least one enlarged groove, valley, channel, indentation and/or other recess which may be mated or interfaced with features or members to further enhance the strength and/or rigidity of the resulting load bearing structure as discussed above. In some embodiments, the enlargement may include a hollow space within the body of the support, as illustrated with hollow space 20a within a support 20 in
(67) In some embodiments, the hollow supports may include an additional feature for enhancing the strength and/or rigidity of the resulting load bearing structure by reinforcing and/or closing off the hollow space, such as illustrated with the capping feature 13c in
(68) In other embodiments, the hollow space 13 may be tapered. When tapered, the features may also be correspondingly tapered to better mate with the depressions. In one aspect, the taper may be towards the top of the supports 20-28, for example, similar to
(69) In some embodiments, the bottom of the polymeric core may include at least one depression, such as a groove, valley, indentation or channel, for example, which may run substantially the entire length and/or breadth of the bottom of the polymeric core, as illustrated in
(70) As illustrated, the depressions 15-1 may generally be separated and/or not connected to other features, such as the depressions 13, 13′, for example, such that they may maintain their integrity along the entire length to provide better strength and/or rigidity rather than if they were interrupted. They may also accommodate an insert or other features which may be mated to the depressions 15-1, which themselves may also be full length and provide better strength and/or rigidity rather than if they were multiple pieces or otherwise interrupted. The longer depressions 15-1 may be spaced apart and substantially parallel to each other, running substantially the width or the breadth of the bottom side of the polymeric core 10.
(71) As mentioned above, the depressions 15-1, 13 or 13′ may be present as at least one single depression or at least a group of depressions. The group of depressions, for example, 15-1, are of closely spaced, parallel depressions, such as grooves, valleys, indentations or channels. A group may be similar in appearance to a single depression as shown in 15-1, but in closer examination or if enlarged, one may discern at least two or more closely spaced depressions. The depressions within a group may or may not be of identical length, shape or depth. The internal spacing between a group of depressions may be smaller than the spacing between adjacent groups, if present. The groups of depressions, if present, may also be interposed with single depressions.
(72) At least one of the depressions, may be mated with a corresponding feature 17. In one embodiment, all of the depressions may be mated with a corresponding feature 17. In another embodiment, not all the groups of depressions, if more than one group is present, is mated to a corresponding feature 17. In a further embodiment, not all the depressions within one group may be mated to a corresponding feature 17.
(73) As noted, the depressions, for example, 15-1, may have different lengths and may be present at different locations on the load bearing structure. Literally many different combinations of depressions may be present, such and combinations of different lengths, widths, depths and shapes and number(s) of single or group depressions in a single load bearing structure. Without being bound to any particular theory, the depressions, such as depressions 15-1, may not necessarily need to run the entire length or breadth of the polymeric core 10 to achieve the desired strengthening and/or increase in rigidity, as, for example, loading on the polymeric core 10 may generally be present mostly in the center or inwards from the edges 12, such that the increased strength or rigidity may generally be more desirable towards the interior rather than at the edges 12. The reduced length may generally also leave residual areas near the edges 12 which may not flex or bend as easily as if the depressions ran the full length, as the full-length depressions may promote flexing perpendicular to the span of the depressions.
(74) As mentioned before, the corresponding feature for each depression, whether the depression is part of a group or not, may include at least one raised portion 17a for each depression and may or may not include any flat portions 17b, for example, wing-like portions. In some embodiments, the feature for a group of depressions, if all depressions in a group are mated with a feature 17, may include at least two raised portions 17a that may have a cross-section of any shape, or combination of any shape, for example, a substantially dome-like cross-section, a substantially rectangular cross-section, a substantially triangular cross-section or similar, with or without flat portions 17b, for example, wing-like features, extending from the lower portion of both sides of the central portion 17a. The raised portions 17a, if more than one group is present, may have a cross-section of any shape, or combinations of any shape, for example, a substantially dome-like cross-section, a substantially rectangular cross-section, a substantially triangular cross-section or similar, with or without flat portions 17b, for example, wing-like features, extending from the lower portion of both sides of one central portion 17a. When mated, the central portion 17a may substantially fill in one of the at least one depressions, 15-1 for example, groove, valley, indentation or channel of the respective shapes. The central portions as well as the wing-like features, if present, may be adhered or bonded, directly or indirectly, to the underside of the polymeric core. For a given load bearing structure having such depressions with or without corresponding features, the core may be combined with one or two polymeric films or sheets. In one embodiment, the feature may cover or combine with the polymeric core prior to the covering or combining of the polymeric core with one or more polymeric sheets or films. In another embodiment, the feature may cover or combine with the load bearing structure after the covering or combining of the polymeric core with one or more polymeric sheets or films.
(75) As mentioned above, in one aspect of any of the above embodiments described and/or shown, one or multiple rows of the at least one depression, for example, grooves, valleys, indentations, or channels on the underside of the core may be present along one direction on the underside of the core and at least one corresponding feature mated with one of the at least one grooves, valleys, indentations or channels. In another aspect of any of the above embodiments described, though not specifically shown when the at least one depression is present on the bottom of the support 20-28, but similar to
(76) As shown in
(77) In an example, the at least one depression 15 or 15′ that span, for example, at least about 75%, more for example, at least about 80%, even more for example, at least about 85%, of substantially the length or the width of the load bearing structure, the one depression may include a single depression or a group of closely spaced parallel depressions, all of the same length, but may or may not be of the same width or depth.
(78) Load bearing structures generally support loads many times their own weight. For example, about 10 to about, 20 times, more for examples, about 15 to about 18 times. If the structures do not have the desired load bearing capabilities, deformation or sagging of the structure may occur after more than about 1 day, more for example, after more than about 3 days, even more for example, after more than about 7 days. These sagging may occur around the center or towards the peripheral of the structure. These capabilities may be tested and/or measured using established, standard test procedures, such as ASTM test procedures. One such testing procedure may be ASTM D1185-2009 section 8.4 (bending test) and structures need to pass such tests. Passing the test is important also for safety reasons. A structure that deforms more than the standard may deform too much, possibly lead to safety issues.
(79) In static testing, bending tests are performed on load bearing structures. As mentioned above, the thicker the core, the better are the chances of such structures passing the test. However, when the requirement of restricted space competes with the requirement to produce a good product, without sacrificing either, the present inventive structures with longer depressions mated with corresponding features may maintain the same advantages as, or even more advantageous, than a plurality, for example, at least three, more for example, at least five, of substantially shorter depressions that are mated with corresponding features. In some of these embodiments, as noted above, thickness of the core may be from about 120 mm to about 130 mm without increasing the density of the core.
(80) As mentioned above, the load nearing structure of the present invention in particularly situated for air transportation of cargo with restricted space. This improved load bearing properties of load bearing structures of the present invention with the potential for decreasing the overall thickness and/or weight of the load bearing structure may, in some instances, for example, in air transportation of cargos of smart phones, tablets, or other similarly thin products, actually allow a shipper to ship an additional or more row of product per load bearing structure without additional weight, or with minimal increase in weight, resulting in further savings.
(81) In some embodiments, additional features may be present intermittently or continuously around some of the edges. The features may generally improve or increase the strength of the edges of the load bearing structure, thus minimizing wear or breakage during use or repeated use. In general, additional features such as edge protectors as described herein may be included. The edge protectors are efficient in protecting and improving the strength of the edges from wear. However, as noted above, such features also add to the weight of the load bearing structure when used.
(82) The present invention further relates to features that may improve the strength of the edges and not add to the weight of the load bearing structure. In face such features may lower the weight of the load bearing structure. The core may include portions of bened edges or jagged edges, such as saw-tooth like edges. The perspective view of an example of the polymeric core 10 having such features may be seen in
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(84) As usual, the form or shape of the core decides the final form or shape of the load bearing structures. The jagged edge of the core is reserved after combining with a polymeric sheet or film.
(85) The new edge protection feature, for example, roughened edge(s), may be present in any of the embodiments described herein as well as any embodiments without any of the above described depressions if edge protection is the main purpose.
(86) In one exemplary embodiment, a load bearing structure for loading, transporting or storing cargo having an expanded polymeric core having a top side, a bottom side and a width having a thickness therebetween joining the top side and the bottom side about the edges; and at least one polymeric sheet having a first side with outer edges are combined with said expanded polymer core on said bottom side, and at least a portion of the thickness of the width of said expanded polymeric core, respectively with at least one feature for decreasing the total weight of the load bearing structure and increasing the strength of at least one of said edges of the load bearing structure, said feature comprises portions of roughened edges. The load bearing structure may or may not include supports extending form the bottom side of the polymeric core. This load bearings structure may or may not include any depressions or group of depressions, as descried above.
(87) In some embodiments, the corresponding feature or member may generally be made from the same or similar material to the polymeric core or polymeric sheets, as discussed below, such as, for example, polystyrene or high impact polystyrene (HIPS), for better compatibility during covering, combining or bonding. It may also be desirable to use the same or similar material such that the entire load bearing structure may, for example, be disposed of or recycled as a single unit instead of needing separation of materials. In general, the feature or member may be formed from a stronger and/or more rigid material than the overall polymeric core to provide more substantial reinforcement from a minimal addition of material. For example, a plurality of feature or member may add at least 10 to 15% of increased overall strength and/or up to 25% additional racking strength, such as with the addition of 8 feature or members 17 into the grooves 13, 13′. The feature or member may be, for example, manufactured by extrusion, casting injection molding, and/or any other appropriate technique. The features or members may, for example, be formed in a length and cut to size or fit the appropriate groove.
(88) In addition to the same or similar materials to the polymeric sheets, suitable materials for the features or members, whether those that are present on the load bearing structure before or after the combining or bonding of the core to the sheet or sheets, may include any metallic and polymeric material, as long as such material may be fabricated into the resulting rigid or substantially rigid parts. Examples of appropriate materials may include, but are not limited to, for example, a polymer that may be molded, thermoformed or cast. Suitable polymers include polyethylene; polypropylene; polybutylene; polystyrene; polyester; polytetrafluoroethylene (PTFE); acrylic polymers; polyvinylchloride; Acetal polymers such as polyoxymethylene or Delrin (available from DuPont Company); natural or synthetic rubber; polyamide, or other high temperature polymers such as polyetherimide like ULTEM®, a polymeric alloy such as Xenoy® resin, which is a composite of polycarbonate and polybutyleneterephthalate, Lexan® plastic, which is a copolymer of polycarbonate and isophthalate terephthalate resorcinol resin (all available from GE Plastics); liquid crystal polymers, such as an aromatic polyester or an aromatic polyester amide containing, as a constituent, at least one compound selected from the group consisting of an aromatic hydroxycarboxylic acid (such as hydroxybenzoate (rigid monomer), hydroxynaphthoate (flexible monomer), an aromatic hydroxyamine and an aromatic diamine, (exemplified in U.S. Pat. Nos. 6,242,063, 6,274,242, 6,643,552 and 6,797,198, the contents of which are incorporated herein by reference), polyesterimide anhydrides with terminal anhydride group or lateral anhydrides (exemplified in U.S. Pat. No. 6,730,377, the content of which is incorporated herein by reference) or combinations thereof. Some of these materials are recyclable or be made to be recyclable. Compostable or biodegradable materials may also be used and may include any biodegradable or biocompostable polyesters such as a polylactic acid resin (comprising L-lactic acid and D-lactic acid) and polyglycolic acid (PGA), polyhydroxyvalerate/hydroxybutyrate resin (PHBV) (copolymer of 3-hydroxy butyric acid and 3-hydroxy pentanoic acid (3-hydroxy valeric acid) and polyhydroxyalkanoate (PHA) copolymers, and polyester/urethane resin. Some non-compostable or non-biodegradable materials may also be made compostable or biodegradable by the addition of certain additives, for example, any oxo-biodegradable additive such as D2W™ supplied by (Symphony Environmental, Borehamwood, United Kingdom) and TDPA® manufactured by EPI Environmental Products Inc. Vancouver, British Columbia, Canada.
(89) In addition, any polymeric composite such as engineering prepregs or composites, which are polymers filled with pigments, carbon particles, silica, glass fibers, or mixtures thereof may also be used. For example, a blend of polycarbonate and ABS (Acrylonitrile Butadiene Styrene) may be used. For further example, carbon-fiber and/or glass-fiber reinforced plastic may also be used.
(90) Useful metals or metallic materials may include metal and metal alloys such as aluminum, steel, stainless steel, nickel titanium alloys and so on.
(91) Moisture, dirt and/or left over products and microbes that thrive on either moisture, dirt or left over products may cause contamination of the products or cross-contamination at the least, and may also rendered non-useable or dangerous to re-use without prior vigorous decontamination when the structure is being reused for cargos that are different from previous cargo, for example, different food types, such as poultry, fresh vegetables, and fresh fruits, or even same types of products. Even if the load bearing structures are newly made, dirt and/or moisture and microbes that thrive on either dirt or moisture may cause contamination of the cargo loaded on the structure. The dirt and/or moisture and microbes may tend to hide, grow or accumulate in interfaces between layers of materials if there is imperfect joining and/or bonding of the layers.
(92) In general, during the normal bonding of the polymeric film to the polymeric core, heat and/or pressure is used so that portions of the polymeric core proximal to the surface of the bottom side 18 with portions of the polymeric sheet 67 proximal to the surface of the bottom side of the sheet 67 to form a substantially strengthened composite. Additionally, a portion of the polymeric core that is proximal to the edge 12 and in a proximal relationship to the bottom side 18 is combined with portions of the polymeric sheet 67.
(93) However, even though the bonding between the bulk of the polymeric core and the polymeric sheet is sufficiently strong, with or without imperfections, to produce a strengthened load bearing structure, the need to improve the bonding between the peripheral of the polymeric sheet and the polymeric core may still be present to minimize or eliminate any imperfections where the dust, dirt and/or moisture and microbes may tend to hide, grow or accumulate, generally in interfaces between layers of materials if there is imperfect joining and/or bonding of the layers.
(94) The load bearing structure or the platform 10, as shown in
(95) Any application of the sealing feature is close to the outer edges of the polymeric sheet or sheets, at the, for example, peripheral of the outer edges of the polymeric sheet 67 or sheets, 67, 68. It is sufficient that a relatively small portion of the outer edges may be sealed by the sealing feature, though a larger portion may also be sealed. For example, about 4 millimeters to about 12 millimeters from the edge, more for example, about 5 millimeters to about 10 millimeters from the edge, and more for example, about 5 millimeters to about 8 millimeters from the edge, of a polymeric sheet is sealed with the sealing feature. The rest of bonded area of the polymeric sheet including the outer edges is bonded with heat and/or pressure in the manufacturing process of the load bearing structure, as noted above. In
(96) Examples of heat activatable adhesives may include, but not limited to adhesives containing ethylene alpha olefin interpolymers, such as those disclosed in U.S. Pat. Nos. 6,319,979, 6,107,430 and 7,199,180; Metallocene based adhesive including those containing substantially linear ethylene/l-octene copolymer, available from The Dow Chemical Company, those disclosed in U.S. Pat. Nos. 8,222,336 and 8,163,833; Metallocene hot melt adhesive including those disclosed in U.S. Pat. No. 8,476,359; propylene based hot melt adhesive including those containing nonmetallocene, metal-centered, heteroaryl ligand-catalyzed propylene and ethylene copolymer adhesives; reactive hot melt adhesive as disclosed in U.S. Pat. No. 8,507,604; heat activated hot melt adhesives including those disclosed in U.S. Pat. Nos. 8,475,046 and 8,240,915; adhesives containing metallocene and non-metallocene polymers, such as those disclosed in U.S. Pat. No. 8,475,621; adhesives containing ethylene .alpha.-olefin, such as those disclosed in U.S. Pat. No. 6,107,430; hot melt adhesives containing block copolymers, such as those disclosed in U.S. Pat. No. 8,501,869; Polyolefin adhesives such as those disclosed in U.S. Pat. Nos. 8,283,400 and 8,242,198, all of which are hereby incorporated by reference in their entirety.
(97) The sealing liquid may be any solvent that may slightly dissolve the core and/or the polymeric sheet during sealing, provided the liquid is not toxic. It is also desirable that the liquid has a moderate to high a solubility index for the core and/or the polymeric sheet, so that a small amount of the liquid is adequate. The liquid may be slightly volatile or relatively non-volatile at ambient temperature. Examples may include chlorinated solvent such as Tetrachloroethylene; or some cyanoacrylate compositions. The liquid may be applied to the edges of the interface between the polymeric sheet and core or between two polymeric sheets via a dispensing device, as discussed above. An example is shown in
(98) The sealing chemical composition may include any liquid that is relatively non-volatile and may be in the form of a liquid, a treated form such as a semi-liquid composition including a mix ire of liquid and solid particles, or a slurry, a solid form such as a capsule of any liquid adhesive or sealing composition. Examples of useful liquid adhesives may include those containing cyanoacrylate or derivatives, or chlorinated solvents noted above mixed with polymeric particles.
(99) Treated sealing chemical compositions such as a slurry may be less volatile than pure solvents or even chemical compositions and thus may be amenable to be painted on in addition to being dispensed from a dispensing device such as a container like a squeeze bottle or a syringe, as above, but with a larger opening on its dispensing end onto either the edges of the polymeric sheet either prior to or after the bonding process between the core and the sheet, depending on the activation temperature of the composition. In some embodiments, the slurry composition may include a mixture of a sealing liquid noted above with same or similar powder polymeric material used in the manufacturing of the polymeric sheet. For example, when the polymeric sheets are made from high impact polystyrene (HIPS), the powder may include powdered polystyrene. The sealing liquid may be relatively non-volatile so that the liquid is not substantially evaporated prior to the bonding process between the sheet with the core and/or sheet. One example may include a solvent mixed with a solid, such as tetrachloroethylene solvent mixed with HIPS powder, to form a slurry which may be applied as noted above. This slurry may dry after application and the particles may, for example, aid in sealing if heat activated in a later stage.
(100) When the treated chemical sealing composition is in a solid form that may include small encapsulated particles, encapsulating any liquid that may be a solvent, a slurry or a sealing composition, inside, and the activation may be the application of pressure or heat and pressure, to crush or melt the capsules and release the adhesive.
(101)
(102)
(103) The sealing feature may also lie between the sheets 67, 68 at the edge, similar to that in
(104) In other embodiments, as illustrated in
(105) In still other embodiments, as illustrated in
(106)
(107)
(108) In another embodiment, as shown in
(109)
(110) In still other embodiments, as illustrated in
(111) Also, in
(112) The sealing liquid may be applied as a sealing feature 70, 80, as described above, and may be applied before or after a polymeric sheet is bonded to the polymeric core. The sealing liquid may also be applied to the polymeric sheet(s). If the liquid is applied prior to the completion of the bonding of the film 67 or 68 to the core 10a or to each other, the sealing liquid may be activatable at the temperature and/or pressure of the bonding of the sheet 67 or 68 to the core 10a, as discussed above. In some embodiments, as described above, the sealing liquid may also be injected beneath the polymeric sheet after completion of the bonding of the sheet 67 or 68 to the core and/or each other and thus may not need to be activatable at the temperature and/or pressure of the bonding of the sheet 67 or 68 to the core 10a, as discussed above.
(113) A sealing chemical composition may be in treated solid or native liquid form, or even in slurries, and may generally be applied to the edges of the polymeric sheet before its bonding to the core and its sealing property may generally be activated during the bonding process, as discussed above. In one embodiment, the chemical composition in liquid form may be encapsulated in a capsule. The capsules do not adhere to each other so that they come in free flowing forms. However, the capsules may adsorb or be attracted to the surface of the foam or polymeric sheet so that they may be applied, for example, by sprinkling onto the surfaces to be sealed prior to the bonding process. The composition may be activated by heat and/or pressure during the bonding process of the core to the sheet. In another embodiment, the chemical composition may be applied directly in liquid form, similar to the application of the sealing liquid, discussed above, and may or may not need to be activatable at the temperature and/or pressure of the bonding of the sheet 67 or 68 to the core 10a, as also discussed above. For example, as noted above, the liquid chemical composition may also be mixed with polymeric particles to form slurry. In this embodiment, when the polymeric sheets are made from high impact polystyrene, then the powder is powdered polystyrene. The sealing liquid may be relatively non-volatile so that the liquid is not substantially evaporated prior to the bonding process between the sheet with the core and/or sheet. The chemical sealing composition may also include a self-healing and/or self-repairing composition. This may be desirable as the sealing features may be present in high stress, high damage and/or high wear areas and may increase in effectiveness and/or usage life of the load bearing structures through the use of self-healing/self-repairing materials.
(114) When a sealing tape is used, the tape may include one side having a contact or tacky adhesive and another side with a heat activatable adhesive. The tacky or contact adhesive side may be covered by a liner and the tape may be wound into a roll, as shown in
(115) The heat activatable adhesive may include hot melt adhesive, a heat curable adhesive, or a reactive adhesive, on the other side. The heat activatable adhesive may be selected to be activated at the temperature during the bonding process.
(116) In some embodiments, the sealing features 70, 80 may include a self-healing and/or self-repairing composition, as mentioned above. This may be desirable as the sealing features 70, 80 may be present in high stress, high damage and/or high wear areas and may increase in effectiveness and/or usage life of the load bearing structure through the use of self-healing/self-repairing materials. For example, some polymers are capable of healing and/or repairing tears and/or other damage by contact repolymerization and/or contact adhesion of adjacent edges of the polymer material. This may include, for example, polymers which repolymerize with themselves when exposed to ultraviolet light and/or other electromagnetic radiation and/or heat. For example, polyurethane-chitosan blended polymers may repolymerize using ultraviolet light to heal tears and/or other discontinuities. For further example, a new class of polymers formed from a condensation reaction between paraformaldehyde and 4,4′-oxydianiline developed by IBM may also be utilized. As noted above, the self-healing and/or self-repairing composition may be present in any of the various sealing features discussed.
(117) In other embodiments, the sealing features 70, 80 may include a melted, welded, sintered and/or other heat/pressure joining of the materials in the polymeric sheet(s), such as polymeric sheets 67, 68, and/or the polymeric core 10a. For example, ultrasonic welding may be utilized to melt and/or join the edges of the polymeric sheet(s) together and/or to the polymeric core 10a by localized heating. The joining area may also be subjected to pressure.
(118) In some embodiments, as illustrated in
(119) In some embodiments, the load bearing structure 10 may also include grooves, détentes, and/or other physical features for denoting where the polymeric sheet(s) may be trimmed and/or cut, an example of which is illustrated with groove 12d in
(120) In some embodiments, as discussed above, edge protecting features, including but not limited to such as shown in
(121)
(122) As discussed, the end edges 12c of the depressions 12b may be present on the polymeric core 10a and the edge protectors may be placed in the depressions 12b between the end edges 12c, such that they may be flushed or substantially flushed with the rest of the polymeric core 10a. After covering with the polymeric film or sheet, the protectors may or may not be easily visible and/or discernable. If the protectors themselves are not visible or discernable when in place on the polymeric core 10a, indicator features may be present, such as, for example, the end edges 12c may be visible as lines and/or discernable by tactile inspection as a thin indentation.
(123) In some embodiments, the edge protectors may have an L-shaped cross-section, such as illustrated with the L-shaped edge protector 11 with an outer surface 11a which may, for example, contact the cargo-holding item, and an inner surface 11b which may contact the depression 12b, as shown in
(124) In other embodiments, the edge protectors may have a substantially C-shaped cross-section, as illustrated with C-shaped edge protector 11′ with an outer surface 11a which may, for example, contact the cargo-holding item, and an inner surface 11b which may contact the depression 12b, as shown in
(125) In some embodiments, edge protectors may also include guides and/or other features for holding a cargo-holding item, as illustrated in
(126) In some embodiments, the protector(s) may be present on the core prior to the covering of the core by the polymeric sheet, as discussed above. In one aspect, the core may be indented to accommodate the protectors so that the protectors are flushed with the core so that the sheet may cover the core with protectors as if the protectors are not present, as discussed and illustrated above with
(127) The protectors may be constructed from any polymeric or metallic materials, or combinations thereof, that may be easily molded or cast into the desired shape and are rigid or substantially rigid or possess sufficient reinforcement for the edges. In one embodiment, when the protectors are present on the core prior to the covering of the core by the polymeric sheet or sheets, the protectors may be made of same or material having similar bonding properties as the sheet to facilitate the bonding of the protector both to the sheet and/or core at the bonding temperature of the sheet to the core. This may be further desirable as the load bearing structure may be more easily and/or readily recycled when composed of substantially a single material. When the edge protectors are present on the core, the polymeric sheet or sheets may or may not be combined or bonded to the edge protectors if the edge protectors are not made with similar material or the edge protectors are not combined or bonded to the polymeric sheet or sheets, the outer edges of the sheet may be bonded to the edge protector by the sealing feature.
(128) In another embodiment, when the protectors are added to the load bearing structure after bonding of the sheet or sheets to the core, any material may be used for the protectors.
(129) In addition to the same or similar materials to the polymeric sheets, suitable materials for the edge protectors, especially those that are present on the load bearing structure after the bonding of the core to the sheet or sheets, may include any metallic and polymeric material, as long as such material may be fabricated into the resulting rigid or substantially rigid parts. Examples of appropriate materials may include, but are not limited to, for example, a polymer that may be molded, thermoformed or cast. Suitable polymers include polyethylene; polypropylene; polybutylene; polystyrene; polyester; polytetrafluoroethylene (PTFE); acrylic polymers; polyvinylchloride; Acetal polymers such as polyoxymethylene or Delrin (available from DuPont Company); natural or synthetic rubber; polyamide, or other high temperature polymers such as polyetherimide like ULTEM®, a polymeric alloy such as Xenoy® resin, which is a composite of polycarbonate and polybutyleneterephthalate, Lexan® plastic, which is a copolymer of polycarbonate and isophthalate terephthalate resorcinol resin (all available from GE Plastics); liquid crystal polymers, such as an aromatic polyester or an aromatic polyester amide containing, as a constituent, at least one compound selected from the group consisting of an aromatic hydroxycarboxylic acid (such as hydroxybenzoate (rigid monomer), hydroxynaphthoate (flexible monomer), an aromatic hydroxyamine and an aromatic diamine, (exemplified in U.S. Pat. Nos. 6,242,063, 6,274,242, 6,643,552 and 6,797,198, the contents of which are incorporated herein by reference), polyesterimide anhydrides with terminal anhydride group or lateral anhydrides (exemplified in U.S. Pat. No. 6,730,377, the content of which is incorporated herein by reference) or combinations thereof. Some of these materials are recyclable or be made to be recyclable. Compostable or biodegradable materials may also be used and may include any biodegradable or biocompostable polyesters such as a polylactic acid resin (comprising L-lactic acid and D-lactic acid) and polyglycolic acid (PGA), polyhydroxyvalerate/hydroxybutyrate resin (PHBV) (copolymer of 3-hydroxy butyric acid and 3-hydroxy pentanoic acid (3-hydroxy valeric acid) and polyhydroxyalkanoate (PHA) copolymers, and polyester/urethane resin. Some non-compostable or non-biodegradable materials may also be made compostable or biodegradable by the addition of certain additives, for example, any oxo-biodegradable additive such as D2W™ supplied by (Symphony Environmental, Borehamwood, United Kingdom) and TDPA® manufactured by EPI Environmental Products Inc. Vancouver, British Columbia, Canada.
(130) In addition, any polymeric composite such as engineering prepregs or composites, which are polymers filled with pigments, carbon particles, silica, glass fibers, or mixtures thereof may also be used. For example, a blend of polycarbonate and ABS (Acrylonitrile Butadiene Styrene) may be used. For further example, carbon-fiber and/or glass-fiber reinforced plastic may also be used.
(131) Useful metals or metallic materials may include metal and metal alloys such as aluminum, steel, stainless steel, nickel titanium alloys and so on.
(132) To aid to keep the protectors on the core prior to bonding and during the bonding process, an adhesive or double-coated adhesive tape may be used. This may be desirable as, for example, the protectors may not significantly adhere and/or grip the load bearing structure prior to the bonding process. Examples of the adhesive may include pressure sensitive adhesive, for example, a hot melt pressure sensitive adhesive or a non-hot melt pressure sensitive adhesive. Examples of double-coated tape may include double coated pressure sensitive adhesive tape, for example, a double-coated hot pressure sensitive tape or a double-coated non-hot melt pressure sensitive tape. The thickness of the adhesive or tape may be thin so that it does not contribute to the thickness of the edge protectors substantially and/or to prevent the edge protectors from protruding significantly from the surface of the load bearing structure. In some embodiments, the adhesive or tape may be substantially melted during the bonding process. The amount of adhesive or tape may also be minimal as to not contribute significantly to the overall material composition of the load bearing structure, as this may be further desirable as the load bearing structure may be more easily and/or readily recycled when composed of substantially a single material.
(133) In other embodiments, the protectors may use friction fits, roughened and/or textured contact surfaces and/or other mechanical means for attaching and/or holding them in place on the load bearing structure.
(134) To keep the edge protectors firmly in place when the protectors are present after the bonding process, a structure adhesive may be used, such as those used in edge sealing described above or later, so that the edge protectors do not detach or move about during and after strapping to keep the cargo in place.
(135) The protectors may have any thickness, as long as they provide the needed reinforcement for the edges. Some materials possess higher rigidity than others and therefore thinner protectors may have sufficient rigidity. For those that are more flexible, thicker components may be needed to provide sufficient rigidity.
(136) The edge protectors may be manufactured by molding or casting. In one embodiment, the edge protectors may be made in bulk and then cut to size. In another embodiment, the edge protectors may be individually made to size. The substantially L-shaped edge protectors 11 and the substantially C-shaped edge protectors 11′ may also be desirable as the continuous cross-sectional shape may allow them to be formed by extrusion as a continuous length which may be cut to size.
(137) In one embodiment, as shown in
(138) In some instances, the dimension of a load bearing structure may be adjusted to match the dimension of a cargo and as such may minimize damage to the outer edges of the load bearing structures by cargo holding items. In such instances, though damage to the structure may not be as severe without edge protectors or roughened edge portions, adjusting the dimensions of the load bearing structures to match a cargo may not be a good solution, for example, as it may increase the cost of having to manufacture load bearing structures with many different dimensions for accommodating various cargo sizes.
(139) For a load bearing structure without edge protector or roughened edge portions, when cargo holding items are used, such as straps, tiedowns, cables, ropes and/or other items, the outer edges tend to collapse when no edge protector or roughened edge portions are present, as shown in
(140) As noted before, the roughened edges, such as the features 12f as illustrated in
(141) The loading bearing structure of the present invention, which may be a dunnage platform or container, may have anti-microbial properties, as noted above Antimicrobial means an agent that is active against one or more organisms including bacteria, viruses, fungi, protists, helminths and insect larvae. Foreign hosts mean a microbe, pathogen or organisms that can be transported on a surface of a load bearing structure. The antimicrobial agent may be in powder form or in liquid form.
(142) In one exemplary embodiment, an antimicrobial agent capable of eliminating, preventing, retarding or minimizing the growth of microbes may be present on the exposed surfaces, for example, top side 16, the width 12a and/or the bottom side 18 of loading bearing structure 10, as shown in
(143) In any of the embodiments, the antimicrobial properties may be generated from materials including chemical anti-microbial materials or compounds that are capable of being substantially permanently bonded, at least for a period such as the useful life of the load bearing structures, either when at least one antimicrobial agent is added to the material used for making the polymeric layer, for example, a sheet mentioned above, or when at least one antimicrobial agent having some surface activity is coated onto the exposed surface of the polymeric layer, for example, sheet mentioned above; or maintain their anti-microbial effects when at least one antimicrobial agent is coated with the aid of coating agents, onto the exposed surface of the polymeric layer, for example, sheet mentioned above. In one example, the chemicals may be deposited on the surface of the loading bearing structures by covalent linkage.
(144) When the antimicrobial agent or agents are incorporated in the material used in making the polymeric layer, for example, a sheet, the agent or agents maybe dispersed directly into the material, or with the aid of an appropriate carrier, for example, a binding agent, a solvent, or a suitable polymer mixing aid. These carriers may also be useful for coating aids mentioned above. Effective binding agents are those that do not interfere with the antimicrobial activities of the antimicrobial agent. In one embodiment, when the anti-microbial agent is incorporated into the material used for making the polymeric layer, for example, a sheet mentioned above, the antimicrobial agent maybe master batch in the material, or an appropriate carrier at a higher concentration prior to adding to the material for making the polymeric layer, for example, a sheet in desired proportions. In another embodiment, the antimicrobial agent may be added directly to the material for making the polymeric layer, for example, a sheet without the intermediate step.
(145) In other embodiments, the antimicrobial agents, either in coatings or incorporated into the materials for making the polymeric layer, may include chemical antimicrobial materials or compounds that may be deposited in a non-permanent manner such that they may slowly dissolve, slowly leach or otherwise deliver antimicrobial substances during use. The material may be adequately incorporated, though temporarily and/or in sufficient amounts to last at least for a period such as the useful life of the load bearing structures, either when at least one antimicrobial agent is added to the material used for making the polymeric layer mentioned above, or when at least one antimicrobial agent is coated onto the exposed surface of polymeric layer, for example, the sheet mentioned above; or maintain their anti-microbial effects when at least one antimicrobial agent is coated with the aid of coating agents, onto the exposed surface of the polymeric layer, for example, a sheet mentioned above. The suitable agent or agents are those that tend to slowly migrate or non-leaching, as defined herein, to the surfaces to provide antimicrobial properties to the surfaces.
(146) In still other embodiments, the antimicrobial agent either in coatings or incorporated into the material used for making the polymeric layer, may include sources of anti-microbial agents which may leach and/or release agents in a moist environment or upon contact with moisture. These sources may be incorporated into the substrate materials used for manufacturing the polymeric layer, for example, sheet mentioned above. Incorporation of these sources may be especially suited to polymeric substrates.
(147) Chemical antimicrobial materials or compounds may include a variety of substances including, but not limited to antibiotics, antimycotics, general antimicrobial agents, quaternary ammonium cations, a source of metal ions such as metal ion generating materials, triclosan, chlorhexidine or any other materials capable of generating an antimicrobial effect, and/or any other appropriate compound or mixtures thereof.
(148) In yet further embodiments, antimicrobial activity may be achieved by utilizing the antimicrobial properties of various metals, especially transition metals which have little to no effect on humans Examples may include sources of free silver ions, which are noted for their antimicrobial effects and few biological effects on humans Metal ion antimicrobial activity may be created by a variety of methods that may include, for example, mixing a source of a metal ion with the polymeric layer, for example, sheet material during manufacture, coating the surface by methods such as plasma deposition, loosely complexing the metal ion source by disrupting the surface of the polymeric layer, for example, coating or sheet to form affinity or binding sites by methods such as etching or coronal discharge, and depositing a metal onto the surface by means such as electroplating, photoreduction and precipitation. The coated surface may then slowly release free metal ions during use that may produce an antimicrobial effect.
(149) In some embodiments, a layer of substantially non-permanent coating including an anti-microbial compound may be present on top of a layer of a substantially permanent coating including an anti-microbial compound.
(150) The substantially permanent anti-microbial coating may be, for example, substantially flexible so that the coating substantially covers the working surfaces of the loading bearing structure during use even if the structure flexes. If the anti-microbial compound is not capable of forming a substantially flexible coating by itself, then a binding agent capable of forming a substantially flexible coating may be used to aid in the flexibility of the resulting coating.
(151) The details of antimicrobial coatings and agents can be found in U.S. patent application Ser. No. 13/549,474, entitled “A LOAD BEARING STRUCTURE HAVING ANTIMICROBIAL PROPERTIES”, the contents of which are hereby incorporated by reference in their entirety.
(152) The load bearing structure may also include a plurality of bridges, runners, wear resistant members and/or connectors that may be affixed to the second side of at least some of the extensions or supports 20-28 of all of the embodiments of loading bearing structures described herein. Wear resistant members may generally be attached to the bottom of some of the plurality of supports so that they may protrude from the bottom of the supports and aid in the wear of the supports. Details of the wear resistant members may be found in U.S. Pat. Nos. 7,908,979, and 5,868,080, the contents of all of which are hereby incorporated by reference.
(153) These wear resistant members may be similar to bridges or runners that extend between adjacent extensions or supports. In some embodiments, only one of these members may be present. In other embodiments, two of these may be arranged in the shape of a cross. In further embodiments, one of each may be attached to each pair of adjacent extensions or supports around the peripheral of the load bearing structure. In still other embodiments, they may be attached to every pair of extensions or supports of the load bearing structure.
(154) Runners, bridges and/or other connectors may also be included, such as, for example, connecting multiple supports, which may generally increase the strength and/or rigidity of the base.
(155) As mentioned above, the runners or bridges may be attached to the bottom of the supports, either flushed with the bottom portions of the supports, for example, attached within an indented portion formed in the bottom of the supports, such as shown in
(156) As mentioned above, for light weight load bearing structures, the core 10a is generally made of foam, for example, a closed cell foam core 10a such as an expanded polystyrene core 10a with a region proximal to its surface that is combined with a polymeric layer, for example, high impact polymeric sheet 67, for example, a polystyrene sheet, by heat and/or pressure.
(157) The foam core 10a may be made from already manufactured bulk form, such as expanded polystyrene foam which may be cut to the desired shape and size. The foam density may also be varied, depending on the degree of expansion of the beads used to make the foam. The foam density may also decide the suitable load or cargo to be loaded.
(158) The foam core in general by itself, unless it is of higher density, for example, the beads are not highly expanded, may not have sufficient structural strength to be useable as a load bearing platform. A dunnage platform with sufficient strength may be formed by combining the core 10a with a high impact polymeric sheet 67, for example, a polystyrene Sheet.
(159) For any polymeric core used, the polymeric sheet or film may be chosen for better compatibility in bonding or combining with the polymeric core. In general, the film or sheet may include any polymeric material capable of being formed into a sheet or film and may include acrylonitrile butadiene styrene; polyester; polystyrene; polycarbonate; PET; APET; PETG; lead free PVC; copolymer polyester/polycarbonate; and HDPE. For example, for polystyrene foam, a high impact polystyrene sheet or film may be desirable. In addition, a high impact polystyrene sheet or film also exhibits high strength so that a thinner sheet or film may be used.
(160) As noted above, the feature may also be made of the same or similar material as the covering film or sheet. This may also facilitate the bonding of the feature with the film or sheet.
(161) In one embodiment, the sheet 67 may include an antimicrobial agent, which may be added to the material used for making the sheet 67. The antimicrobial agent may be in powder form or in liquid form. In another embodiment, at least one antimicrobial agent may be coated onto the exposed surface 16 of the sheet 67. The antimicrobial agent may be in powder form or in liquid form. When the agent is coated, the coating may take place before the sheet 67 is combined with the core 10a or after the load bearing structure 10 is made.
(162) The combination may be affected by heat and/or pressure. In one specific example of a load bearing structure, a combination process may cause portions of an expanded polystyrene core 10a proximal to the bottom side 18 to be combined with the high impact polystyrene sheet 67 to form a strengthened polystyrene by heat and pressure. Additionally, a portion of the expanded polystyrene that is proximal to the edge 12a and in a proximal relationship to the bottom side 18 may be combined with the high impact polystyrene by heat and pressure to form the strengthened polystyrene, if desired. Details of this combination process may be found in U.S. Pat. No. 6,786,992, the content of which is incorporated herein by reference in its entirety.
(163) Another specific example of a load bearing structure 10 may be as disclosed in U.S. Pat. No. 7,908,979, WO04041516 and U.S. Pat. No. 7,413,698, the contents of all of which are incorporated herein by reference in their entirety.
(164) In another exemplary embodiment, any of the load bearing structures described above, as shown for example, in
(165) The containers may have a base in the structure of, for example,
(166) In another embodiment, as shown in
(167) In another exemplary embodiment of the invention, a knock down or collapsible container for storage and/or shipping having a base, four walls extending therefrom and a top panel to form an enclosure therein, each of which having an inside surface, an outside surface, a width joining the inside and outside surfaces, and four inside edges and four outside edges. The base, four walls extending therefrom and a top panel may be constructed from the load bearings structure of the present invention. The container when collapsed or knock-down, has a foot print not larger than the foot print of the largest individual component, as shown in
(168) Interlocking features characteristics may also be defined as a depression in a wall of a container corresponding to a protrusion in the cargo such that the container ‘mates’ with the cargo without requiring a fastener. Interlocking characteristics may include respective depression and protrusion features on adjacent connecting components. For example, when the features along one side have a receiving characteristic, the features on the adjacent member are of a protruding characteristic so that the interlocking features mate to form a container without any aid from additional clips or fasteners. The phrase ‘without requiring a fastener’ means that the interlocking features are interlocked without the aid of any component that is not the base, the four walls or the top. Additional securing devices may be employed to insure further integrity of the container, if needed, and such additional securing devices may include straps and/or shrink wrap packaging. In one embodiment, each of the walls, top and base of the container may be made of a light weight core substantially covered with a polymeric layer, for example, high impact sheet, having antimicrobial properties or having at least one antimicrobial agents incorporated therein or thereon, on at least one of its surfaces to form a load bearing structure having a width as noted above. In another embodiment, a structural metal mesh may be inserted into the core to resist piercing of the surface, and each of the walls, top and base of the container may be made of a light weight core substantially covered with a polymeric layer, for example, high impact sheet, with or without antimicrobial properties or having at least one antimicrobial agents incorporated therein or thereon, on at least one of its surfaces to form a load bearing structure having a width as noted above.
(169) In general, the side pieces 801, 802, 803 and 804 may include edges orthogonal to ridges which correspond to the grooves of the top 816 and base 812, as illustrated in the top view of the container 800 in
(170) These embodiments of the container are described in detail in U.S. patent application Ser. Nos. 13/549,472, and 14/158,488, both entitled “Cargo Container for Storing and Transporting Cargo”, the contents of all of which are hereby incorporated by reference in their entirety.
(171) In a further exemplary embodiment, the container includes two identical substantially L-shaped cross-section halves, 380, each having at least two walls and a base or top component, each of the components having corresponding or complementary interlocking features to be mated together to form a container having an enclosure therein, as shown in
(172) According to one embodiment, the container may include an enclosure having one undivided internal compartment, as shown in
(173) The containers may be made of the size and shape to accommodate the cargo, or the cargo may be contained in its own packaging and then inserted into the container.
(174) In some embodiments, the container having an enclosure may also be made up of a knock down or collapsible container 200 for storage and/or shipping, as illustrated in
(175)
(176) In general, the base 230, as illustrated in
(177) In general, the top panel 210, as illustrated in
(178) Each of the wall panels 220 may generally include a rectangular panel 222 with four edges with interfacing features. In some embodiments, three of the four edges may be formed as stepped edges with a portion of the overall thickness of the rectangular panel 222 extending outward, such as to form a partially circumferential step, such as illustrated in
(179) The stepped edges 226a, 226b, and 226c may generally be shaped to fit into grooves of other components of the container 200, such as, for example, the edge 226a fitting into circumferential groove 216 of top panel 210 shown in
(180) In other embodiments, the wall panels 220, as illustrated in
(181) The inner panel 226 may generally include interfaces which extend past the edges of the outer panel 222 except on the edge with the corner interface 234, such as with extensions 226a, 226b and 226c, as illustrated. The extensions 226a, 226b and 226c may generally be shaped to fit into grooves of other components of the container 200, such as, for example, the extension 226a fitting into circumferential groove 216 of top panel 210 shown in
(182) In some embodiments, the wall panels 220 may be identical and may form a container with a square cross-section. This may be desirable as the total number of different components required is three (top panels, bases and wall panels). In other embodiments, wall panels 220 of different dimensions may be used, for example, with two wall panels of one length and two wall panels of another length, such that the container cross-section will be a rectangle. In general, the dimensions of the top panel 210 and the base 230 may determine the required type of wall panel 220 to be used.
(183) In general, the container 200 may be assembled by interfacing the wall panels 220 with the base 230 and capping with the top panel 210, as illustrated in
(184) The base of a container may generally include a plurality of supports, such as legs, which may take various forms or shapes, such as illustrated with the legs of bases 900, 910 920 and 930 in
(185)
(186) In some other embodiments, the legs may have angled walls and be spaced inward from the outer periphery of the base, such as the legs 914, 924 and 934 of bases 910, 920 and 930, respectively, illustrated in
(187) In addition, the load bearing structure of the present invention may also include ridges, ribs, reinforcements and/or other surface modifications, as shown in
(188) The cargo containers may also include a desiccant to control the humidity of the interior.
(189) In another exemplary embodiment of the invention, the container 200 is formed from two halves, and each of the halves may or may not include the top or the bottom components. The interfacing locking features on the components may include any or all combinations of those described above. In one embodiment, the container 200 includes two identical or mirror images substantially L-shaped cross-sectional halves, such as the halves 220′ illustrated in
(190) In another embodiment of the invention, the container 200 includes two identical or mirror images of substantially L-shaped cross-sectional halves, such as the halves 210′ and 230′ as illustrated in
(191) For a container formed from two identical, substantially L-shaped cross-sectional halves 220′, or walls, each half 220′ may be integrally formed or joined from two of the wall sections 220, as discussed above, to interface with a top 210 and a base 230 component. The wall sections may generally be identical or similar in shape and size, and though integrally formed or joined together, each still kept its distinct platform portion 228. The halves 220′ may further include all of the features of the constituent wall sections 220, as above, except where the halves 220′ are integrally formed, the features that would normally interface the two constituent wall sections 220 may be absent and may instead form a solid continuous structure. In these embodiments, each half 220′ includes two vertical edges, such as interfaces 224 and 226b, and two horizontal edges, such as 226a and 226c, to interconnect with other components, for example, with each other and with the top 210 and base 230 to form the container 200 with internal space 201, as illustrated in
(192) In one embodiment, one substantially L-shaped cross-sectional half may be integrally formed or joined with a top component, as shown with half 210′ formed from wall sections 220 joined to the top 210 as illustrated in
(193) For the halves 210′, 220′, 230′ as described above, the edges may be rounded or chamfered, as illustrated with, for example, the rounded edges 223, or they may also be substantially 90 degree interfaces which are not rounded or smoothed (not shown).
(194) As noted above, the interfacing features may be formed during any step of the manufacturing process. In one example, the features may be molded when the components are made. The base, top or walls may include a light weight core, for example, a closed cell foamed core, combined with or surrounded by a polymeric film to form a strengthened structure. The core may include the interfacing features and the polymeric film may then conform to the features in the core during the combining or surrounding step or process. In another embodiment, the features may be forged into the components after the components are made. For example, the base, top or walls may include a light weight core, for example, a closed cell foamed core, combined with or surrounded by a polymeric film to form a strengthened structure. The core does not include any of the interfacing features. The interfacing features may then be forged after the core and film are combined, and the exposed surface of the core may either remain exposed or a spray coating made be added to cover the exposed surface of the core.
(195) In various embodiments of the invention, one or more of the dunnage platform, the first enclosure and second enclosure are formed from a core, from one or more of the materials including expanded polystyrene, polyurethane, polyphenylene ether, polystyrene impregnated with pentane, a blend of polyphenylene ether and polystyrene impregnated with pentane, polyethylene, and polypropylene. In various embodiments of the invention, one or more of the dunnage platform, the first enclosure and second enclosure are formed from a core containing one or more materials mentioned above. In various embodiments of the invention, one or more of the dunnage platform, the first enclosure and second enclosure are formed from one or more thermoplastic sheets or layers including high impact polystyrene; polyolefins such as polypropylene, low density polyethylene, high density polyethylene, polyethylene, polypropylene; polycarbonate; acrylonitrile butadiene styrene; polyacrylonitrile; polyphenylene ether; polyphony ether alloyed with high impact polystyrene; polyester such as PET (polyethylene terephthalate), APET, and PETG; lead free PVC; copolymer polyester/polycarbonate; or a composite HIPS structure, as mentioned above.
(196) In various embodiments of the invention, one or more of the dunnage platform, the first enclosure and second enclosure thermoplastic sheets are a blend of any of the polymers mentioned above. In various embodiments of the invention, one or more of the dunnage platform, the first enclosure and second enclosure are formed from a core with an embedded strengthening material selected from the group consisting of a mesh, a perforated sheet and a barrier is embedded in the core. In various embodiments of the invention, one or more of the dunnage platform, the first enclosure and second enclosure are formed from a core with an embedded strengthening material selected from the group consisting of metal, carbon fiber, Kevlar, basalt-web blanket and Formica. As noted above, when used in facilitating security check of air cargo transport of cargo that is transparent to magnetic scanners, non-metal containers may be used.
(197) As noted above, the polymeric layer, for example, sheets or the coatings thereon the polymeric layer, may include chemical anti-microbial materials or compounds that are capable of being substantially permanently bonded, at least for a period such as the useful life of the loading bearing structure or maintain their anti-microbial effects when coated with the aid of processing aids or coating agents, onto the exposed surfaces of the polymeric layer, for example, sheet or coating 67. In one example, the chemicals may be deposited on the surface of the polymeric layer, for example, sheet or coating 67 or incorporated into the material of the polymeric layer, for example, sheet or coating 67. Antimicrobial activity may be built into the surface 16 itself by, for example, covalently bonding antimicrobial agents to the surface of the polymeric layer, for example, sheet or coating 67, or if incorporated into the bulk of the material for making the polymeric layer, for example, sheet or sprayed coating, may migrate to the surface. These covalently bonded materials may act to minimize microbial growth on the surface, either disposable or reusable. In addition, any microbial organisms that may chance to be attached to the material may be killed by interaction with the coating. For example, quaternary ammonium cations, such as N-alkyl-pyridiniums, may be used as antimicrobial moieties in covalently attached polymeric surface coatings. In one case, poly(4-vinyl-N-hexylpyridinium) (N-alkylated-PVP) was previously noted to have an optimum alkyl side chain length for antimicrobial activity. Polyethylenimine (PEI) was also previously used as a bacteriocidal coating when both N-alkylated on its primary amino group and subsequently N-methylated on its secondary and tertiary amino groups to mise the overall number of cationic quaternary amino groups. Any such covalently bonded quaternary ammonium cation polymeric coatings may be used to give an antimicrobial property to the surface or surfaces of the loading bearing structures. Further examples of quaternary ammonium compounds include, but are not limited to, benzalkonium chloride, benzethonium chloride, methylbenzethonium chloride, cetalkonium chloride, cetylpyridinium chloride, cetrimonium, cetrimide, dofanium chloride, tetraethylammonium bromide, didecyldimethylammonium chloride and domiphen bromide.
(198) For bulk incorporation of the antimicrobial agent or agents into the material used in making the polymeric layer, for example, sheet or sprayed coating, the agent or agents maybe dispersed directly into the material, or with the aid of an appropriate carrier, for example, a binding agent, a solvent, or a suitable polymer mixing aid. These carriers maybe chosen so that they are mixable with the material for making the polymeric layer, for example, sheets or sprayed coatings and compatible with the antimicrobial agent or agents used. Effective binding agents are those that do not interfere with the antimicrobial activities of the antimicrobial agent.
(199) As noted above, an additional enclosure, such as bag like enclosure may be used to cover any of the load bearing structures described above. The present invention also discloses a system designed to facilitate the security checking process, including a light weight load bearing structure for loading perishable or non-perishable cargo, the load bearing structure having a top deck, a bottom deck and a width joining the top and the bottom, the bottom deck having a plurality of legs extending therefrom and the cargo is loaded onto the top deck of the load bearing structure; and a bag-like enclosure for covering the cargo and at least a portion of the width of the load bearing structure, with the bag-like enclosure having an opening with an elastic property about its circumference for stretching about the width of the load bearing structure. The load bearing structure and bag-like enclosure in this configuration are both transparent to magnetic imaging scanners used in security scanning to facilitate the security check of perishable cargo or non-perishable cargo, large or small, without the need for unloading and reloading of the cargo from the load bearing structure.
(200) The bag like enclosure may be made from a film, a woven sheet or a non-woven sheet having sufficient strength for stretching over and covering a cargo and light weight enough not to add unnecessary weight to the cargo. It may be closed on three sides and opened at one end, with the open end having some elastic property circumferentially about the opening. The cargo may be packed and the bag-like material stretched over the entire cargo with the open end stretched under the edge of base and tagged at the origin and the complete structure may be shrink-wrapped. The surfaces of the bag-like material may also have anti-microbial properties. Any of the antimicrobial embodiments described above may be suitable. More details are found in U.S. patent application Ser. No. 13/549,477, entitled “SYSTEM FOR FACILITATING SECURITY CHECK OF SHIPMENT OF CARGO”, the content of which is hereby incorporated by reference in its entirety.
Example 1: Load Testing of Dunnage Platform without Long Features
(201) A sample of a dunnage platform having the form of the polymeric core 10 of
(202) TABLE-US-00001 TABLE 1 Maximum Deflections Measured (mm) at Unsupported Supports Day Support 25 Support 24 Support 23 0 0 0 0 1 5.8 7.87 9.24 2 7.72 10.02 10.53 3 9.16 12.53 12.91 4 10.03 13.47 13.75 5 10.87 14.3 14.95 6 11.5 14.91 15.08 7 11.73 15.31 15.43 8 12.42 15.89 15.79
(203) The maximum deflection measured after 192 hours was 15.89 mm.
Example 2: Load Testing of Dunnage Platform with Long Features
(204) A sample of a dunnage platform having the form of the polymeric core 10 of
(205) TABLE-US-00002 TABLE 2 Maximum Deflections Measured (mm) at Unsupported Supports Hours Support 25 Support 24 Support 23 0 0 0 0 24 2.24 2.19 1.72 96 4.57 4.15 3.76 192 6.25 5.84 4.75
(206) The maximum deflection measured after 192 hours was 6.25 mm. This polymeric core 10 with features 17 inserted into depressions 15-1 exhibited significantly less deflection under a higher load than the sample utilized in Example 1 despite being thinner.
Example 3: Load Testing of Thin Dunnage Platform with Long Features
(207) A sample of a dunnage platform having the form of the polymeric core 10 of
(208) TABLE-US-00003 TABLE 3 Maximum Deflections Measured (mm) at Unsupported Supports Hours Support 25 Support 24 Support 23 0 1.40 1.14 1.47 24 3.23 3.96 3.78 168 6.27 7.84 8.91 336 7.75 10.64 13.17
(209) The maximum deflection measured after 336 hours was 13.17 mm. This polymeric core 10 with features 17 inserted into depressions 15-1 exhibited less deflection over a significantly longer timespan with a similar load than the sample utilized in Example 1 despite being thinner and lighter overall.
(210) While the invention has been particularly shown and described with reference to exemplary embodiments, it should be understood by those skilled in the art that changes in form and detail may be made therein without departing from the spirit and scope of the invention.