Abstract:
A container which is nested along its bottom closure panels in the web to gain additional capacity in a waxing unit. There are oblique outer edges on each of the bottom closure panels which allow the panels to be nested in the blank. All of oblique outer edges of each of the bottom closure panels extend in the same direction creating long and short sections in each of the closure panels which in the finished container interlock to hold the closure panels in a locked position. The oblique edges also provide camming edges which allow the bottom closure panels to be pushed inwardly into the container until they interlock and then snap back into position to form the bottom closure.

Description:
BACKGROUND OF THE INVENTION 
     Many containers used with produce or meat are wax coated or wax impregnated. This allows the meat or produce to be iced during storage and transportation. The containers are wax coated or wax impregnated either by passing the individual container blanks through a molten wax bath or by carrying the individual container blanks through a hood in which the molten wax is sprayed or cascaded onto the blank. These wax applications are slow because the containers must be completely saturated with the molten wax and the molten wax cooled before the container leaves the process. The containers can then be stacked and bundled without adhering to each other. Because the process is slow and time constrained and because the apparatus has a fixed dimension, the number of container blanks which may be wax saturated during any given time period is limited by the size of the apparatus. 
     The containers often are required on a seasonal basis and it usually is desirable to have high and low production periods depending on when the containers are needed. This is not possible normally because only a fixed number of blanks can be treated in a given time period. It is then necessary either to have continuous production throughout the year and carry inventory, to run additional shifts in order to obtain the desired number of wax saturated containers when they are needed or to have an oversized apparatus. 
     These containers often are used in locations such as a produce field where it is difficult to tape or glue the bottom closure panels. For this reason regular slotted containers (RSC) which normally are stitched or glued are not used. A regular slotted container with a snap lock bottom closure is used instead. 
     Buerger, U.S. Pat. No. 2,513,079 granted June 27, 1950; Sax, et al, U.S. Pat. No. 3,960,313 granted June 1, 1976 and Stolkin, et al, U.S. Pat. No. 4,007,869 granted Feb. 15, 1977 show snap lock bottom closures. The Buerger patent is exemplary. In this patent the fold-back flaps 42 and 43 are adhered to their adjacent flaps and when the container is squared the bottom closure snaps into place. The snap lock bottom requires additional fold-back and adhering operations in its manufacture. 
     The snap lock bottom type constructions require spot gluing with specific placement of the adhesive if the container is to function properly. The snap lock bottom also requires nonrectangular adhesive patterns. In a wax saturated container the adhesive must be of a special type in order to fasten to the fibers in the containerboard. 
     The Buerger patent also discloses the nesting of the top closure panels on the web. Other patents which describe nesting of blanks on a web are FIGS. 8-10 of Schillinger, U.S. Pat. No. 3,679,124 granted July 25, 1972; Demby, et al, U.S. Pat. No. 3,285,492 granted Nov. 15, 1966; and British Pat. No. 859,905 published Jan. 25, 1961. 
     SUMMARY OF THE INVENTION 
     The inventors were presented with a two-fold problem. It was necessary to provide a container which could be sent to a produce field in a flat condition and be set up by hand in the field. It was also necessary to keep the number of manufacturing operations to a minimum. A container having a bottom closure which did not require a gluing operation in the manufacturing plant and did not require glue, stapling or taping in the field would be preferred. 
     They were able to provide within this design limitation a bottom closure configuration which allowed the containers to be erected and the bottom closures locked by hand in the field. 
     This was done by providing oblique outer edges on each of the bottom closure panels. All of the oblique outer edges of each of the bottom closure panels extend in the same direction. This creates long and short sections in each of the closure panels which in the finished container interlock to hold the closure panels in locked position. The oblique edges also provide camming edges which allow the bottom closure panels to be pushed inwardly into the container until they interlock and then snap back into position to form the bottom closure. 
     This provides a container which is easily set up and has bottom closure panels which are easily interlocked. The container has the ease of setup of a snap lock bottom but does not have the problems associated with the snap lock container. There is no need of pattern gluing or additional manufacturing steps to form a snap lock bottom. 
     This design created the second problem. The interlocking feature on the bottom closure panels caused these panels to be longer from their hinge line to their outer edge than normal bottom closure panels and an individual container blank to take more room in the waxing facility, decreasing production. The second problem was how to bring the capacity of the waxing facility back to normal. 
     They were able to accomplish this by reversing the orientation of the bottom closure panels of a second container blank and nesting the two blanks along the bottom closure panels. Now the blanks took the same amount of space as two of the normal style blanks, and the same number of blanks could be processed in the waxing facility. The inventors were able to provide a better bottom closure with no decrease in capacity in the waxing facility. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top plan view of the nested two container blank in the form used for wax impregnation. 
     FIGS. 2-3 are top plan views of modified nested blanks. 
     FIG. 4 is a top plan view of the container blank made from the blank shown in FIG. 1. 
     FIGS. 5-11 are isometric views showing the bottom closure of FIG. 4 being closed and interlocked. 
     FIG. 12 is an isometric view showing the closed upper closure of the container. 
     FIGS. 13 and 14 show the closed and interlocked configuration of the bottom closure panels, FIG. 13 being a bottom plan view and FIG. 14 being a top plan view. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 shows a nested dual container blank 20 which includes the nested container blanks 20a and 20b. The blank 20 is divided by outer or upper longitudinal score lines 21a and 21b and inner or lower longitudinal score lines 22a and 22b into upper closure sections 23a and 23b, side panel sections 24a and 24b and nested lower closure section 25. 
     The upper closure section 23a is divided by transverse slots 26a, 27a and 28a into a first major upper closure panel 29a, a first minor upper closure panel 30a, a second major upper closure panel 31a and a second minor upper closure panel 32a; and the upper closure section 23b is divided by transverse slots 26b, 27b and 28b into a first major upper closure panel 29b, a first minor upper closure panel 30b, a second major upper closure panel 31b and a second minor upper closure panel 32b. 
     The side panel section 24a is divided by transverse score lines 33a, 34a, 35a and 36a into a glue flap 37a, a first major side panel 38a, a first minor side panel 39a, a second major side panel 40a, and a second minor side panel 41a; and the side panel section 24b is divided by transverse score lines 33b, 34b, 35b and 36b into a glue flap 37b, a first major side panel 38b, a first minor side panel 39b, a second major side panel 40b, and a second minor side panel 41b. The score lines 33a and 33b are aligned with the outer side edges of major upper closure panels 29a and 29b; the score lines 34a and 34b are aligned with slots 26a and 26b; the score lines 35a and 35b are aligned with slots 27 a and 27b; and the score lines 36a and 36b are aligned with slots 28a and 28b. 
     The nested lower closure section 25 is divided into separate lower closure sections 25a and 25b of the individual blanks 20a and 20b respectively by the skip-cuts 42, 43, 44 and 45. The distance between cuts in the skip-cuts 42, 43, 44 and 45 may vary from a 3/16 inch nick to a distance of 1/2 inch or greater. It will depend on the amount of corrugated board necessary to hold the two containers together during processing. 
     The nested lower closure section 25 is also divided into individual major and minor lower closure panel sections by the slots 46, 47 and 48. The slots 46, 47 and 48 divide the lower closure section 25 into a first major lower closure panel section 49, a first minor lower closure panel section 50, a second major lower closure panel section 51 and a second minor lower closure panel section 52. The slots 46, 47 and 48 are aligned with the score lines 34a and b, 35a and b, and 36a and b, respectively. 
     Certain of the slots 46, 47 and 48 are relieved as at 53 to allow easier separation of the two container blanks along the skip-cut lines. 
     The skip-cuts 42, 43, 44 and 45 divide each of these individual lower closure panel sections into a pair of lower closure panels. The skip-cut 42 divides the first major lower closure panel section 49 into the first major lower closure panel 49a of container blank 20a and the first major lower closure panel 49b of container blank 20b. The skip-cut 43 divides the first minor lower closure panel section 50 into the first minor lower closure panel 50a of container blank 20a and the first minor lower closure panel 50b of container blank 20b. The skip-cut 44 divides the second major lower closure panel section 51 into the second major lower closure panel 51a of container blank 20a and the second major lower closure panel 51b of container blank 20b. The skip-cut 45 divides the second minor lower closure panel section 52 into the second minor lower closure panel 52a of container blank 20a and the second minor lower closure panel 52b of container blank 20b. 
     The width of nested lower closure section 25, the width between the score lines 22a and 22b, will depend upon the spacing between the free outer edges 42 and 44 of the major closure flaps 49a and 51a. If the edges 42 and 44 abut to form a tight closure, then the width between score lines 22a and 22b will be equal to or substantially equal to the width of a minor side panel 39 or 41. If there is a space between the edges 42 and 44, then the width between score lines 22a and 22b will be less than the width of a minor side panel 39 or 47 and this width will depend upon the space between the edges 42 and 44 in the formed container. If the major bottom closure panels 49a and 51a overlap in the formed container, the width between score line 22a and 22b will be greater than the width of the minor side panels 39. 
     The oblique skip-cuts 42, 43, 44 and 45 may take a number of shapes. These are shown in FIGS. 1-3. In the blanks shown in FIGS. 1-3, the same reference numerals are used for the same parts. 
     In FIG. 1 the oblique skip-cuts 42 and 44 are each formed in three parts. In skip-cut 42, the first outer part 54 is spaced a slight distance from and is parallel to score line 22b, the second outer part 55 is spaced an equal distance from and is parallel to score line 22a. Each of these parts extend a short distance into the first major bottom closure panel section 49. In a container having a major dimension of about 20 inches and a minor dimension of about 12 inches, the parts 54 and 55 would each be spaced approximately 3 inches from its respective score line 22b or 22a and be approximately 3 inches long. Extending between the inner ends of the parts 54 and 55 is the oblique part 56. The skip-cut 44 in the second major bottom closure section 51 has the same configuration, the first and second outer parts 57 and 58 and the oblique part 59 extending between them. Their location and dimensions are as in major closure panel section 49. The skip-cuts 43 and 45 in the minor bottom closure panel sections 50 and 52 extend diagonally across the sections to form two triangular panels 50a and 50b, and 52a and 52b. 
     In FIG. 2 the skip-cuts 42&#39; and 44&#39; dividing the major bottom closure panel sections 49&#39; and 51&#39; are straight oblique lines extending across each section from a point approximately three inches from score line 22a on one end to a point approximately three inches from score line 22b at the opposite end. The skip-cuts 43&#39; and 45&#39; in the minor bottom closure panel section are the same as in FIG. 1. 
     The skip-cuts on the minor bottom closure panel sections may also be changed. This is shown in FIG. 3. The skip-cuts 43&#34; and 45&#34; form trapezoidal minor bottom closure panels 50a&#34;, 50b&#34;, 52a&#34; and 52b&#34;. 
     The width between score lines 22a&#39; and 22b&#39;, and between 22a&#34; and 22b&#34; is the same as between 22a and 22b. Again the width will depend upon whether there is a spacing between free edges 42&#39; and 44&#39; or 42&#34; and 44&#34;, whether they abut in the formed container, or whether the major closure panels overlap. 
     The skip-cuts 42, 43, 44 and 45 in FIG. 1 and the corresponding skip-cuts in FIGS. 2-3 extend obliquely in the same direction. This allows the lower closure panels to interlock in the erect container. 
     The oblique skip-cuts 42, 43, 44 and 45 and the corresponding skip-cuts in FIGS. 2-3 create in each of the bottom closure panels a long section and a short section, the long section being adjacent the long side edge and the short section being adjacent the short side edge of each of the bottom closure panels. In FIG. 1, for example, in major bottom closure panel 49a the long side edge is 60a and the short side edge is 61a, and the long section is 62a and the short section is 63a. In major bottom closure panel 49b the long side edge is 60b and the short side edge is 61b, and the long section is 62b and the short section is 63b. In minor bottom closure panel 50a the long side edge is 64a and the short side edge is 65a, and the long section is 66a and the short section is 67a. In minor bottom closure panel 50b the long side edge is 64 b and the short side edge is 65b, and the long section is 66b and the short section is 67b. In major bottom closure panel 51a the long side edge is 68a and the short side edge is 69a, and the long section is 70a and the short section is 71a. In major bottom closure panel 51b the long side edge is 68b and the short side edge is 69b, and the long section is 70b and the short section is 71b. In minor bottom closure panel 52a the long side edge is 72a and the short side edge is 73a, and the long section is 74a and the short section is 75a. In minor bottom closure panel 52b the long side edge is 72b and the short side edge is 73b, and the long section is 74b and the short section is 75b. In the construction shown in FIGS. 1 and 2 in which the skip-cuts 43 and 45 are diagonal, the short side edges 65a, 65b, 73a and 73b are for practical purposes nonexistent. 
     In any container blank all of the long side edges are on the same side of the blank and in the dual blank there is on any given side edge of a bottom closure section one long side edge and one short side edge as in bottom closure section 49 in which side edges 60a and 61b are on the same side edge. 
     FIG. 4 shows the blank 20a taken from the blank 20 of FIG. 1 and FIGS. 5-14 show the container being formed from this blank. This is exemplary of the containers that also may be formed from the blanks shown in FIGS. 1-3. The blank 20a is formed from blank 20 by separating the blank 20 into blank 20a and 20b along the skip-cuts 42, 43, 44 and 45. The lay-flat container is formed by bending the blank 20a around score lines 34a and 36a and adhering the glue flap 37a to the outer edge of the minor side panel 41a. 
     When the container is to be set up in the field, it is squared around the score lines 33a, 34a, 35a and 36a and the bottom closure panels are folded inwardly in sequence. The sequence is shown in FIGS. 6-11. The drawings show the sequence with the box top side up so the sequence will be described to conform to the drawings. In the field the box will be placed upside down to interlock the bottom closure flaps. 
     The first panel to be folded in is one of the minor bottom closure panels, in this case panel 52a. This is shown in FIG. 6. The next panel is the major lower closure panel 51a, the panel adjacent the long side edge 72a of panel 52a. This is shown in FIG. 7. The short section 71a of panel 51a is now under the long section 74a of panel 52a. 
     The other minor lower closure panel 50a is folded under the major lower closure panel 51a. This is shown in FIG. 8. The short section 67a of panel 50a is now under the long section 70a of panel 51a. Finally the other major lower closure panel 49a is folded under the others as shown in FIG. 9. The panel 49a is pushed into the container body as shown in FIG. 10. The oblique edge 42 of the panel 49a acts as a camming surface to force the other three bottom closure panels inwardly. When the long section 62a of panel 49a is behind panel 52a, then panel 50a forces the panel 49a back into the plane of the bottom closure to lock the four bottom closure panels together as shown in FIGS. 11, 13 and 14. The interlocked bottom closure panels are shown in FIGS. 13 and 14. The long section 62a of major bottom closure panel 49a is over the short section 75a of minor bottom closure panel 52a. The long section 74a of minor bottom closure panel 52a is over the short section 71a of major bottom closure panel 51a. The long section 70a of major bottom closure panel 51a is over the short section of 67a of minor lower closure panel 50a; and the long section 66a of minor lower closure panel 50a is over the short section 63a of major lower closure panel 49a. 
     After the container has been filled with produce the upper panels are closed and fastened in the usual manner. The minor upper closure flaps 30a and 32a are bent inwardly and the major upper closure flaps 29a and 31a are bent over and fastened to the minor upper closure flaps. This is shown in FIG. 12. 
     There are three additional features shown in the blank in FIG. 4. These are the handholds 76 in minor side panels 39a and 41a; the air holes 77 which straddle score line 22a; and the finger holds 78 in the side edges 64a and 72a of bottom closure panels 50a and 52a, respectively. These are exemplary of the types of features that can be placed in the container. 
     The hand holds 76 are shown as hinged along their lower edge at score line 79. The air holes 77 are shown in both the lower edge of the minor side panels 39a and 41a and the hinged edge of the bottom panels 50a and 52a. They can, however, be placed in any convenient location in the container. The finger apertures 78 allow the lower closure panels 50a and 52a to be pulled upwardly to release the interlocked lower closure panels in the erect container. This allows the container to be placed in lay-flat condition again after it has been used. 
     In some constructions, the upper closure flaps 23a and 23b may be eliminated and a telescoping cover may be substituted. 
     The free edges of the major bottom closure panels will abut if the product within the container is being iced and it is desired to retain the ice within the container. In this case, drain holes will be placed in the side panels at or near the bottom of the panel.