Patent Publication Number: US-6904734-B2

Title: Method for packing a primary shipping case

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a division of U.S. patent application Ser. No. 09/680,815, filed Oct. 5, 2000, now U.S. Pat. No. 6,530,480, and which claims the benefit of U.S. provisional patent application Ser. No. 60/157,953, filed Oct. 6, 1999. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to protective shipping cartons and, more particularly, to overpack cartons that are used for packing primary shipping cartons and which provide a high degree of protection to the primary shipping case, are easy to use and are low in cost. 
     BACKGROUND OF THE INVENTION 
     Product cartons, and in particular lamp product cartons, have been commonly shipped in large quantities, typically pallet loads. Pallets include wooden bases and exterior wrapping that provide good support. Pallets are too large to be moved by individuals and are therefore moved slowly and in controlled ways by machines. 
     Current marketing trends indicate that smaller product quantities are frequently ordered. The smaller product quantities are shipped by package carriers and are handled manually. Such shipping frequently results in damaged packages. Lamps are fragile, and broken lamps are unacceptable to customers. To protect the smaller quantities held in a primary shipping case or package, the primary shipping case is enclosed in an overpack carton. Prior art overpack cartons have included a full exterior carton with Styrofoam, polystyrene or cardboard cushions positioned between the primary shipping case and the overpack carton. Frequently, it is difficult to slide the primary shipping case into the overpack carton while retaining the cushions in place. In addition, no overpack carton has been certified by package shippers. Since the packaging is not certified, broken lamp shipments are returned to the vendor at the vendor&#39;s expense. 
     A number of prior art packaging techniques are known. One approach uses a large exterior carton with Styrofoam “popcorn”, wadded newspapers or similar cushioning material between the product package and the exterior carton. This method is not fully reliable, since the inner product package may be positioned too close to an exterior wall, or insufficient filler material may be used to fill the intermediate space. This approach is also costly, since a large exterior carton is used, and an excessive amount of cushioning material is used. The labor associated with this packaging technique is also substantial. 
     A second prior art packaging technique uses a large exterior carton and eight Styrofoam corner cushions. The inner package is then positioned in the exterior carton with the inner package walls and the outer carton walls parallel to each other. Less fill material is used, and the packing process is faster. This approach has been used to pack inner packages of fluorescent lamps. The Styrofoam cushions do not provide good shock resistance, and breakage of the product may occur. The exterior carton is relatively large, and the time for filling and sealing is substantial. This approach has not been certified by package shippers for insurance purposes. 
     A third approach uses an exterior carton into which the inner package is placed, with the inner package walls rotated at 45° relative to the exterior carton walls. Triangular folded cardboard cushions are then inserted between the inner package and a corner of the exterior carton. While four triangular cardboard cushions may be used, in actual practice two are usually positioned on opposite sides of the inner package. This method has also been used to pack inner packages of fluorescent lamps. The method requires an exterior carton that is at least 40% larger than the inner package. Material use is high, and packing is labor-intensive, leading to an expensive overall package. This method has not been certified by package shippers for insurance purposes. 
     Cushioned packaging devices have been disclosed, for example, in U.S. Pat. No. 4,339,039, issued Jul. 13, 1982 to Mykleby; U.S. Pat. No. 5,040,696, issued Aug. 20, 1991 to Liebel; U.S. Pat. No. 1,601,547, issued Sep. 28, 1926 to Wofford; U.S. Pat. No. 5,624,035, issued Apr. 29, 1997 to Kim; and U.S. Pat. No. 3,266,705, issued Aug. 16, 1966 to Wood. All of the known prior art exterior packaging techniques have had one or more disadvantages, including, but not limited to, a failure to adequately protect the inner package, excessively large size and high cost of materials and/or labor. 
     Accordingly, there is a need for improved overpack cartons and methods of packing a primary shipping case. 
     SUMMARY OF THE INVENTION 
     According to a first aspect of the invention, an overpack device is provided for packing a primary shipping case. The overpack device comprises a packing strap including a plurality of panels, at least one cushion secured to the packing strap, and latching elements on the packing strap for latching the packing strap around at least a portion of the primary shipping case with the at least one cushion facing the primary shipping case. 
     According to another aspect of the invention, an overpack carton is provided for packing a primary shipping case. The overpack carton comprises a packing strap including interconnected first, second, third and fourth side panels, and a latching panel connected to the fourth side panel, at least two cushion strips secured to the first, second, third and fourth side panels, and latching elements on the first side panel and the latch panel for latching the packing strap around at least a portion of the primary shipping case. 
     According to a further aspect of the invention, a method is provided for packing a primary shipping case. The method comprises the steps of providing a cushioned packing strap having latching elements, wrapping the packing strap around at least part of the primary shipping case, and interengaging the latching elements. 
     According to another aspect of the invention, an overpack carton is provided for packing a primary shipping case. The overpack carton comprises a packing strap including a plurality of interconnected panels, at least one cushion secured to the packing strap, and at least one closure device for closing the packing strap around at least part of the primary shipping case with the cushion facing the primary shipping case. The closure device may comprise tape, one or more bands, or latching elements on the packing strap. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a better understanding of the present invention, reference is made to the accompanying drawings, which are incorporated herein by reference and in which: 
         FIG. 1  is a perspective view of a first overpack configuration utilizing a full length overpack carton secured around a primary shipping case; 
         FIG. 2  is a cross-sectional side view of the overpack carton, taken along the line  2 — 2  of  FIG. 1 ; 
         FIG. 3  is a cross-sectional end view of the overpack carton, taken along the line  3 — 3  of  FIG. 2 ; 
         FIG. 4  is a top plan view of the unfolded overpack carton, showing a first configuration of the cushion strips; 
         FIG. 5A  is a schematic end view of the unfolded overpack carton as seen along arrows  5 A— 5 A of  FIG. 4 ; 
         FIG. 5B  is a schematic end view of the overpack carton wrapped around the primary shipping case; 
         FIG. 6A  is a schematic end view of an unfolded overpack carton, showing a second configuration of the cushion strip with end corners; 
         FIG. 6B  is a schematic end view of a wrapped primary shipping case, using the second configuration of the cushion strip shown in  FIG. 6A ; 
         FIG. 6C  is a cross-sectional side view of the overpack carton and primary shipping case, taken along line  6 C— 6 C of  FIG. 6B ; 
         FIG. 7A  is a schematic end view of an unfolded overpack carton, showing a third configuration of the cushion strip; 
         FIG. 7B  is a schematic end view of a primary shipping case and overpack carton corresponding to the cushion strip configuration of  FIG. 7A ; 
         FIG. 8A  is a schematic end view of an unfolded overpack carton, showing a fourth configuration of the cushion strip; 
         FIG. 8B  is a schematic end view of a primary shipping case and overpack carton corresponding to the cushion strip configuration of  FIG. 8A ; 
         FIG. 9A  is a schematic end view of an unfolded overpack carton, showing a fifth configuration of the cushion strip; 
         FIG. 9B  is a schematic end view of a primary shipping case and overpack carton corresponding to the cushion strip configuration of  FIG. 9A ; 
         FIG. 10A  is a perspective view that illustrates an initial step of a method for packing a primary shipping case using the overpack carton of  FIGS. 1-5B ; 
         FIG. 10B  is a perspective view of the packing method after the overpack carton has been wrapped around the primary shipping case; 
         FIG. 10C  is a perspective view of the packing method wherein the overpack carton is latched around the primary shipping case; 
         FIG. 10D  is a fragmentary cross-sectional view of the latching mechanism, taken along the line  10 D— 10 D of  FIG. 10C ; 
         FIG. 11  is a perspective view of a second overpack configuration utilizing two end cap overpack cartons; 
         FIG. 12  is a side cross-sectional view of the second overpack configuration, taken along the line  12 — 12  of  FIG. 11 ; 
         FIG. 13  is an end view of the closed end of the overpack carton as seen along arrows  13 — 13  of  FIG. 12 ; 
         FIG. 14A  is a perspective view that illustrates an initial step of a method for packing a primary shipping case using the end cap overpack carton of  FIGS. 11-13 ; 
         FIG. 14B  is a perspective view of the packing method wherein the end flaps are latched in place; 
         FIG. 15A  is a perspective view of another embodiment of the end cap overpack carton; 
         FIG. 15B  is a perspective view of the overpack carton of  FIG. 15A , illustrating latching of the end flaps; 
         FIG. 15C  is an end view of the overpack carton of  FIGS. 15A and 15B ; and 
         FIG. 16  is a cross-sectional side view of a third overpack configuration utilizing two end cap overpack cartons and an intermediate overpack carton. 
     
    
    
     DETAILED DESCRIPTION 
     A first overpack configuration utilizing a full-length overpack carton is illustrated in  FIGS. 1-5B , where like elements have the same reference numerals. An overpack carton  10  is secured around a primary shipping case  12 . In the embodiment of  FIGS. 1-5B , the primary shipping case  12  and the overpack carton  10  have an elongated rectangular configuration, such as may be utilized for packing fluorescent lamps. However, the primary shipping case  12  may have any form factor and size and may contain any product. The overpack carton  10  is shown wrapped around primary shipping case  12  in  FIGS. 1 ,  2 ,  3  and  5 B, and is shown unfolded in  FIGS. 4 and 5A . 
     As best shown in  FIG. 5A , overpack carton  10  includes a packing strap  20 , which may be folding, nonfolding or corrugated paperboard for example. Packing strap  20  includes a first side panel  22 , a second side panel  24 , a third side panel  26 , a fourth side panel  28  and a latching panel  30 . Adjacent panels are interconnected along fold lines  32 . Packing strap  20  has a first end  70 , a second end  72  and sides  74  and  76 . In the embodiment of  FIGS. 1-5B , packing strap  20  preferably has a width along fold lines  52  that is somewhat greater than the length of primary shipping case  12  and a length that permits the overpack carton to be wrapped around primary shipping case  12  with latching panel  30  overlapping side panel  22 , as shown in FIG.  3 . 
     The overpack carton  10  further includes latching elements  38  for latching packing strap  20  around the primary shipping case  12 . In the embodiment of  FIGS. 1-5B , the latching elements are integrally formed in packing strap  20 . The latching elements include first tabs  40  and second tabs  42  formed in latching panel  30 . First slots  50  are formed in first side panel  22 , and second slots  52  are formed along the fold line  32  between first side panel  22  and second side panel  24 . Latching panel  30  is divided along a fold line  56  into a lever panel  60  and a base panel  62 . First tabs  40  are formed in latching panel  30  along fold line  56 . When latching panel  30  is folded along fold line  56 , tabs  40  extend outwardly, as best shown in FIG.  10 B. Second tabs  42  are formed at the edge of latching panel  30 . Tabs  42  may include cuts  44  which permit tabs  42  to be locked into slots  52 . The overpack carton of  FIGS. 1-5B  includes two complete sets of latching elements because it is relatively long. As shown in  FIG. 4 , latching panel  30  may be divided along a line  54  into sections to facilitate independent operation of the latching elements. Other embodiments of the overpack carton may include a single set of latching elements or more than two sets of latching elements. 
     It may be observed that first side panel  22  and latching panel  30  are located at opposite ends of packing strap  20 . The first tabs  40  and second tabs  42  are formed in latching panel  30 , and first slots  50  and second slots  52  are formed in first side panel  22 . When the packing strap  20  is wrapped around primary shipping case  12 , first tabs  40  engage first slots  50  and second tabs  42  engage second slots  52  to provide latching of the overpack carton as described below. 
     The overpack carton  10  further includes at least one cushion for protection of primary shipping case  12 . Preferably, the overpack carton includes at least one cushion strip. The overpack carton  10  shown in  FIGS. 1-5B  includes spaced-apart cushion strips  80 ,  82  and  84  affixed to packing strap  20  by a suitable adhesive. Each of the cushion strips  80 ,  82  and  84  runs lengthwise along packing strap  80 . In particular, cushion strips  80  and  82  are located along opposite sides of packing strap  20 , and cushion strip  84  is located along the center of packing strap  20 . In the embodiment of  FIGS. 1-5B , cushion strips  80 ,  82  and  84  are provided with notches  86  at locations corresponding to fold lines  32  of packing strap  20 . In particular, the apex of each notch  86  is located along one of fold lines  32 . The notches  86  may, but are not required to be, 90° notches. The notches  86  effectively divide the cushion strips into segments corresponding to respective side panels of packing strap  20 . When the overpack carton  10  is wrapped around the primary shipping case  12 , the notches close, as indicated by lines  88  in  FIG. 3 , to form a continuous cushion strip around primary shipping case  12 . As shown in  FIGS. 5A and 5B , segments of cushion strips  80 ,  82  and  84  on side panel  28  are shorter than side panel  28  and have squared off ends. This permits the ends of each cushion strip to abut, as indicated by line  92  in  FIG. 3 , so as to form a continuous cushion strip when the overpack carton  10  is wrapped around primary shipping case  12 . In another configuration, the ends of the cushion strips extend the full length of the side panels and have beveled ends which abut when the overpack carton is wrapped around the primary shipping case, as shown in  FIGS. 6A and 6B . The cushion strips  80 ,  82  and  84  are preferably made of a compressible but resilient foam. One preferred foam material is polyurethane foam. It will be understood that more or fewer cushions strips may be utilized depending on the size of the overpack carton and the required protection of primary shipping case  12 . 
     The packing strap  20  may be provided with optional openings  90  of any desired size or shape which function as hand grips. Because packing strap  20  is spaced from primary shipping case  12  by cushion strips  80 ,  82  and  84 , spaces are provided at openings  90  for gripping overpack carton  10 . 
     The overpack carton  10  is shown wrapped around and latched to primary shipping case  12  in  FIGS. 1-3 . As shown, packing strap  20  is folded along fold lines  32 , and side panels  22 ,  24 ,  26  and  28  are wrapped around the sides of primary shipping case  12 , with latching panel  30  overlapping first side panel  22 . The overlap of latching panel  30  with first side panel  22  permits first tabs  40  to engage first slots  50  and permits second slots  42  to engage second slots  52  for secure latching, as described below. The cushion strips  80 ,  82  and  84  are preferably somewhat compressed and provide resilient support of primary shipping case  12  within packing strap  20 . In addition, cushion strips  80 ,  82  and  84  cause packing strap  20  to be spaced from primary shipping case  12 . 
     In some cases, the overpack carton  10 , including cushion strips  80  and  82 , may extend somewhat beyond the end of primary shipping case  12 , so that primary shipping case  12  is recessed within overpack carton  10 . Thus, although the ends of the overpack carton  10  are open in this embodiment, the edges of the packing strap  20  and the cushion strips  80  and  82  provide protection for the ends of the primary shipping case  12 . In other cases, the overpack carton  10  does not extend beyond the end of primary shipping case  12 . 
     A second configuration of the cushion strip is shown in  FIGS. 6A-6C . Like elements in  FIGS. 1-6C  have the same reference numerals. A cushion strip  100  is provided with notches  86  at locations corresponding to the fold lines  32  of packing strap  20 . In addition, cushion strip  100  is provided with beveled ends  102  and  104  which abut along line  106 , as shown in  FIG. 6B , when the overpack carton is wrapped around primary shipping case  12 . Each of the segments of cushion strip  100  includes a raised edge  110  which defines a step  112 , as best shown in FIG.  6 C. The raised edge  100  provides additional protection of primary shipping case  12  and prevents shipping case  12  from slipping relative to overpack carton  10 . A cushion strip  120  at the opposite end of overpack carton  10  may have a raised edge  122 , as shown in FIG.  6 C. 
     A third configuration of the cushion strip is shown in  FIGS. 7A and 7B . Like elements in  FIGS. 1-5B ,  7 A and  7 B have the same reference numerals. A cushion strip  130  is formed without notches and therefore is not divided into segments. Thus, when the packing strap  20  is wrapped around primary shipping case  12 , cushion strip  130  is deformed and compressed in regions near the corners of primary shipping case  12 , as shown in FIG.  7 B. 
     A fourth configuration of the cushion strip is shown in  FIGS. 8A and 8B . Like elements in  FIGS. 1-5B ,  8 A and  8 B have the same reference numerals. A cushion strip  140  is formed as a series of spaced-apart segments  142 ,  144 ,  146 ,  148  and  150  positioned on packing strap  20  to engage the corners of primary shipping case  12 , as shown in FIG.  8 B. Segments  144 ,  146  and  148  have notches  86  at locations corresponding to fold lines  32  of the packing strap  20 . When packing strap  20  is wrapped around primary shipping case  12 , notches  86  close such that segments  144 ,  146  and  148  form corner cushions, as shown in FIG.  8 B. In addition, segments  142  and  150  abut at one corner of primary shipping case  12  to form a corner cushion. 
     A fifth configuration of the cushion strip is shown in  FIGS. 9A and 9B . Like elements in  FIGS. 1-5B ,  9 A and  9 B have the same reference numerals. A cushion strip  160  is configured as a series of spaced-apart segments  162 ,  164 ,  166  and  168 . Segments  162 ,  164 ,  166  and  168  are located on side panels  28 ,  26 ,  24  and  22 , respectively, of packing strap  20  between fold lines  32 . Thus, when packing strap  20  is wrapped around primary shipping case  12 , segments  162 ,  164 ,  166  and  168  of cushion strip  160  abut the respective sidewalls of primary shipping case  12 , as shown in FIG.  9 B. 
     A method for packing the primary shipping case  12  using the overpack carton  10  of  FIGS. 1-5B  is shown in  FIGS. 10A-10D . Like elements in  FIGS. 1-5B  and  10 A- 10 D have the same reference numerals. Initially, the overpack carton  10  is in an unfolded state, as shown in FIG.  10 A. Primary shipping case  12  may be positioned on one of the side panels of packing strap  20 , such as side panel  26 , and packing strap  20  is wrapped around primary shipping case  12  by folding packing strap  20  along fold lines  32 . Wrapping of packing strap  20  around primary shipping case  12  is represented in  FIG. 10A  by arrows  170 . Packing strap  20  is positioned such that cushion strips  80 ,  82  and  84  are on the inside of the overpack carton facing primary shipping case  12 . As shown in  FIG. 10B , the ends of the packing strap  20  are positioned with first side panel  22  under latching panel  30 . 
     Latching panel  30  is then folded along fold line  56  such that lever panel  60  angled relative to base panel  62 , thereby extending first tabs  40  toward first slots  50 , as shown in FIG.  10 B. First tabs  40  are fixed to lever panel  60 , so that first tabs  40  are aligned with first slots  50  in side panel  22  when level panel  60  is an upright position. Then, first tabs  40  are inserted into first slots  50 , as illustrated in  FIGS. 10B and 10D , and lever panel  60  is pivoted about fold line  56 . The pivoting movement of tab  40  in slot  50  causes latching panel  30  to move to the right in  FIG. 10D  relative to side panel  22 , thereby tightening packing strap  20  around primary shipping case  12  and compressing cushion strips  80 ,  82  and  84 , at least slightly. Lever panel  60  is pivoted about fold line  56  such that second tabs  42  can be inserted and locked in second slots  52 , as illustrated in  FIGS. 10C and 10D . The overpack carton  10  is thus securely latched around primary shipping case  12  with cushion strips  80 ,  82  and  84  at least slightly compressed to securely hold primary shipping case  12 . The overpack carton  10  is easily removed from primary shipping case  12  by reversing the above process, and can be reused if desired. 
     It will be understood that a variety of different latching elements may be utilized within the scope of the invention. The latching elements may, but are not required to be, integrally formed on packing strap  20 . One or more sets of latching elements may be utilized, depending on the size of the overpack carton and the required latching integrity. Alternatively, tape or bands  180 , shown in phantom in  FIG. 1 , may be used to close overpack carton  10 . 
     A second overpack configuration in accordance with the invention is shown in  FIGS. 11-14B . The configuration of  FIGS. 11-14B  utilizes end cap overpack cartons  200  and  202  for packing of primary shipping case  12 . The end cap overpack cartons  200  and  202  are wrapped around opposite end portions of primary shipping case  12  and provide protection for the ends of primary shipping case  12 . 
     Overpack carton  200  includes a packing strap  210 , having four side panels and a latching panel, cushion strips  212  and  214  and latching elements  220 . The configuration of packing strap  210 , cushion strips  214  and latching elements  220  may be similar to the overpack cartons shown and described above, with appropriate adjustment for the smaller width of the packing strap. As shown in  FIG. 14A , packing strap  210  includes a first side panel  222 , a second side panel  224 , a third side panel  226 , a fourth side panel  228  and a latching panel  230 . The overpack carton  202  at the opposite end of primary shipping case  12  may have the same configuration as overpack carton  200 . 
     The overpack carton  200  further includes end flaps  240 ,  242 ,  244  and  246  connected along fold lines  248  to side panels  222 ,  224 ,  226  and  228 , respectively. End panels  240  and  244  are provided with tabs  250 , and end panels  242  and  246  are provided with slots  252 , as best shown in FIG.  14 A. When the packing strap  210  is wrapped around primary shipping case  12 , end flaps  240 ,  242 ,  244  and  246  are folded inwardly as shown in FIG.  14 B and tabs  250  are inserted into the respective slots  252  to secure end flaps  240 ,  242 ,  244  and  246  in positions which protect the end of primary shipping case  12 . 
     It will be understood that the end flaps  240 ,  242 ,  244  and  246  are not required in the end cap overpack carton and that the overpack carton  200  may have an open end of the type shown in FIG.  1 . Furthermore, the full-length overpack carton shown in  FIGS. 1-5B  and described above may utilize end flaps if desired. The end flaps may partially or fully enclose the end of the overpack carton. 
     A second configuration of the end cap overpack carton is shown in  FIGS. 15A-15C . Like elements in  FIGS. 11-15C  have the same reference numerals. An end cap overpack carton  260  is similar to overpack carton  200  shown in  FIGS. 11-14B , except for the configuration of the end flaps. End flaps  270 ,  272 ,  274  and  276  are connected along fold lines  278  to side panels  222 ,  224 ,  226  and  228 , respectively. End flaps  270  and  274  each have an arrangement of notches  280  and  282  that define slots when the end flaps  270  and  274  are folded together, as shown in FIG.  15 C. End flap  272  includes a tab  290  and a tab  292  and is provided with a fold line  294 . End flap  272  is folded along fold line  294  such that tab  292  may be inserted in the slot defined by notches  282 . The flap is then pivoted about fold line  294  such that tab  290  may be inserted in the slot defined by notches  280 . This arrangement provides latching of end flaps  270 ,  272 ,  274  and  276  and some compression of cushion strip  212 . The latching arrangement for the end flaps shown in  FIGS. 15A-15C  is similar to the latching arrangement for the side panels on the overpack carton as described above. 
     A third overpack configuration in accordance with the invention is shown in FIG.  16 . The overpack configuration of  FIG. 16  includes end cap overpack cartons  300  and  302  latched around opposite end portions of primary shipping case  12  and an intermediate overpack carton  310  latched around an intermediate portion of primary shipping case  12 . The end cap overpack cartons  300  and  302  may be constructed as described above in connection with  FIGS. 11-14B  or  FIGS. 15A-15C . Intermediate overpack carton  310  may be a short version of the full-length overpack carton shown in  FIGS. 1-5B  and described above. It will be understood that both the end cap overpack cartons  300  and  302  and the intermediate overpack carton  310  may have any convenient width. A wider intermediate overpack carton  312  is shown in phantom is FIG.  16 . The width of the overpack cartons depend on the length of the primary shipping case and the required coverage of primary shipping case  12  by the combined overpack cartons. 
     The overpack cartons described above have been designed for packaging an elongated, rectangular primary shipping case. It will be understood that the overpack carton can be configured for packaging a primary shipping case of any size, shape and form factor. For example, the primary shipping case is not necessarily elongated and is not necessarily rectangular. Furthermore, the primary shipping case may have any number of sides. 
     While there have been shown and described what are at present considered the preferred embodiments of the present invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined by the appended claims.