Quality-enhancing pizza carton

[0002] This is a continuation-in-part application of my application Ser. No. 09/061,302, entitled “Designer Pizza Box with Enhancements,” filed Apr. 16, 1998, now U.S. Pat. No. 5,961,035, which is a continuation-in-part of application Ser. No. 08/731,586, entitled “Multi-function Pizza Carton,” filed Oct. 16, 1996, now U.S. Pat. No. 5,833,130.

[0003] This invention relates to cartons made of foldable material and, in particular, to paperboard boxes for food products such as pizza.

[0004] Each year millions of hot pizzas are sold for delivery and carry-out. The physical and perceived quality of those pizzas are, in large part, determined by the type of packaging used for transporting them.

[0005] Packaging-related problems pertaining to delivery/carry-out pizza include:

[0006] 1) Pizza-sliding during transport, resulting in deformed pizza and slice separation;

[0007] 2) Pizza deformation while sliding a cut pizza into the box and deformation of the side walls while cutting a pizza in the box;

[0008] 3) Loss of heat by conduction from the box bottom into the customer's table top, resulting in “cold pizza;”

[0009] 4) Condensation development on the customer's table in the area under the box, resulting in the bottom panel of the box absorbing the condensation and becoming soggy and imparting a “cardboard smell” to the pizza;

[0010] 5) Downward warping of the box cover resulting in the cover contacting the pizza and cheese sticking to the cover;

[0011] 6) Floppy box structure resulting in drooping of a loaded box and accidental cover opening.

[0012] Regarding problem #1, the best solution is to provide a pizza box with at least six sides and preferably eight sides. The prior art discloses various types of pizza boxes with six or more sides. Three of the most commonly used structures are disclosed by Zion et al. U.S. Pat. No. 4,765,534 granted Aug. 23, 1988, Ritter U.S. Pat. No. 5,368,225 granted Nov. 29, 1994, and Philips et al. U.S. Pat. No. 5,702,054 granted Dec. 30, 1997. Other prior art disclosing pertinent structure for boxes with six or more sides include Lund, Jr. U.S. Pat. No. 3,923,234 granted Dec. 2, 1975, Deiger U.S. Pat. No. 5,000,374 granted Mar. 19, 1991, Philips U.S. Pat. No. 5,110,039 granted May 5, 1992, Barlow U.S. Pat. No. 5,522,537 granted Jun. 4, 1996, Correll U.S. Pat. No. 5,586,716 granted Dec. 24, 1996, and Correll U.S. Pat. No. 5,713,509 granted Feb. 3, 1998.

[0013] The optimal solution for reducing slice-sliding is an eight-sided box. However, an eight-sided box provides no square corner for packing extra items, such as a sauce cup or a pepperoncini, in with the pizza. Therefore, there remains a problem of how to contain a pizza on eight sides will providing a square corner for packing extra items. The prior art do not solve this problem but my invention does.

[0014] Regarding problems #2-5, the prior art do not solve those problems but, again, my invention does.

[0015] Regarding problem #6, some prior art provide for a rigid box structure, but most of those boxes require unusual or awkward folding methodology. My invention, on the other hand, provides for a rigid box while allowing for a folding technique similar to that employed for erecting a standard pizza box.

[0016] Three previous patents of mine—namely, U.S. Pat. No. 5,806,755 (Product-protecting Pizza Carton) granted Sep. 15, 1998; U.S. Pat. No. 5,833,130 (Multi-function Pizza Carton) granted Nov. 10, 1998; and U.S. Pat. No. 5,881,948 (Expandable Pizza Box and Method of Use) granted Mar. 16, 1999—disclose inventive structure and methods for resolving some of the above problems and, thereby, provide means for enhancing the quality of delivery/carry-out pizza. This patent discloses further inventive structure and, in certain aspects, combines that new structure with the structure of those three prior patents to produce an even higher level of pizza quality enhancement.

[0017] So, there has remained a need for resolving the above-described quality-related problems. These problems have not been solved by the prior art but are solved by my invention(s). By solving these problems a pizza company can provide a higher-quality delivery/carry-out pizza.

[0018] Accordingly, the general object of my invention is a carton that provides a means of enhancing the real and perceived quality of delivery/carry-out pizza. More specifically, the object of my invention is a carton that does one or more of the following: (1) reduces slice sliding with eight-sided containment while providing a square corner for packing an extra item, (2) makes it easier to slide a cut pizza into the box, (3) makes it easier to cut a pizza inside the box, (4) reduces heat loss from conduction on a customer's table, (5) reduces the amount of condensation on a table top in the area below a loaded pizza box, (6) reduces the chance of the bottom panel of the box becoming soggy from absorbing condensation off a table top, (7) reduces the chance of the box cover warping downward into a pizza, and (8) provides a means for increasing box rigidity and reducing the chance of accidental cover opening.

[0019] The advantage of my invention is enhanced real and perceived quality of delivery/carry-out pizza and resulting increased customer satisfaction and sales.

[0020] Further objects and advantages of the invention will become apparent from consideration of the following detailed description, related drawings, and appended claims.

[0021] My invention is a carton that can incorporate one or more of the following features:

[0022] 1) An improved fall-back side wall structure comprising a side wall, a fall-back corner flap, and a verticalizing structure having a diagonal wall;

[0023] 2) An improved corner wall structure comprising a diagonal wall and a plurality of hingedly connected connector panels, wherein at least one of the connector panels is disposed at an oblique angle to the bottom panel of the box;

[0024] 3) One or more thermal-legs projecting downward from a rear wall on a box, the box having a straight front wall, first and second side walls adjacent the front wall, and first and second diagonal walls attached to the rear ends of the first and second side walls;

[0025] 4) Cover anti-shift means comprising first and second tabs projecting inward from a top edge of a double-panel front wall structure and disposed adjacent the ends of a cover front flap.

[0026] Regarding feature #1, my U.S. Pat. No. 5,833,130 (Multi-function Pizza Carton) granted Nov. 10, 1998, discloses a type of fall-back side wall structure in combination with a V-wall structure. However, that patent does not disclose a fall-back side wall structure in combination with a conventional straight front wall structure, as provided by the instant invention. Also, my U.S. Pat. No. 5,881,948 (Expandable Pizza Box and Method of Use) granted Mar. 16, 1999, discloses a type of fall-back side wall structure having a single verticalizing flap attached to a rear end of a fall-back side wall. However, that patent does not disclose a verticalizing structure having a diagonal wall attached to the rear end of a side wall, as provided by the instant invention.

[0027] Regarding feature #2, my U.S. Pat. No. 5,806,755 (Product-protecting Pizza Carton) granted Sep. 15, 1998, discloses a corner wall structure having a plurality of hingedly connected connector panels where at least one of the connector panels is disposed at an oblique angle to the bottom panel of the box. However, that patent does not disclose a type of corner wall structure in combination with an end wall having an end edge disposed at an obtuse angle to a bottom edge of the wall, as provided by the instant invention. Further, patent '755 does not disclose a corner wall structure being hingedly connected to the bottom panel of the box, as provided by the instant invention. Finally, patent '755 does not disclose a blank having a second connector panel having a second connector edge disposed at an obtuse angle to a rear end edge of the bottom panel, as provided by the instant invention.

[0028] Regarding feature #3, my U.S. Pat. No. 5,833,130 (Multi-function Pizza Carton) and my patent application Ser. No. 09/061,302 (Designer Pizza Box with Enhancements) each disclose a box having a thermal-leg. However, neither discloses a thermal-leg projecting from a rear wall of a box having a straight front wall disposed parallel to the rear wall in combination with first and second side walls disposed adjacent the front wall and first and second diagonal walls attached to rear ends of the side walls, as provided by the instant invention.

[0029] Finally, the improved fall-back side wall structure provided herein is combined with various inventions disclosed in my U.S. Pat. Nos. 5,806,755 and 5,833,130 and 5,881,948. The overall result is an improved quality-enhancing pizza carton. Those prior inventions include product anti-slide means (i.e., anti-slide cover flaps), anti-warp flex-lines, thermal-legs, square-corner-forming means, and a pizza-clearing notch in the ancillary panel of a double-panel wall.

[0030] My invention typically would be used for packaging relatively flat food products such as pizza; however, it could take other forms for other purposes, as well.

[0031] A complete understanding of the invention can be obtained from the detailed description that follows.

[0032] FIG. 1 is a plan view of a blank of the preferred embodiment of the invention.

[0033] FIG. 2 is a perspective view of a fully-erected carton formed from the blank of FIG. 1.

[0034] FIG. 3 is a perspective view of a partially-erected carton formed from the blank of FIG. 1.

[0035] FIG. 4 is a rear elevation view of the fully-erected carton.

[0036] FIG. 5 is a plan view of a section of the blank of FIG. 1 showing the corner wall structure.

[0037] FIG. 6 is a plan view of a section of a blank having a first alternate corner wall structure.

[0038] FIG. 7 is a plan view of a section of a blank having a second alternate corner wall structure.

[0039] Between drawings, like reference numerals designate corresponding parts.

[0040] Referring now to the drawings, there is illustrated a preferred embodiment of the invention in the format of a one-piece corrugated paperboard blank and, correspondingly, in the formats of fully-erected and partially-erected boxes created from the blank. The intended use for the embodiment is as a food carton or, specifically, a pizza box. However, it will be appreciated, as the description proceeds, that my invention may be realized in different embodiments and may be used in other applications.

[0041] FIG. 1 shows a blank 10 and FIGS. 2 and 3 show a fully-erected carton 12 and partially-erected carton 14, respectively, created from blank 10. Most referenced components are labeled in FIG. 1; selected components are labeled in other Figures. Corresponding parts between drawings share a same reference numeral. It is noted that the invention is bilaterally symmetrical. Therefore, pairs of opposing like components are to be found, with one item of the pair on each side of the box or blank. For simplicity of labeling, each component pair may be indicated by a numeral on one side of the drawing only. When this occurs, it is to be understood that the discussion also applies to the corresponding component on the other side, even though that component may not be numerically labeled.

[0042] Referring now to blank 10 shown in FIG. 1 and also to corresponding boxes 12 and 14 shown in FIGS. 2 and 3, there is a non-rectangular bottom panel 20 which has a front end edge 22, a rear end edge 24, and a pair of opposing side edges 26.

[0043] Attached to bottom panel 20 are a double-panel front wall structure 30, a fully-reclinable rear wall 40, and a pair of opposing fall-back side wall structures 50.

[0044] Front wall structure 30 has a front wall 32 attached to bottom panel front end edge 22 and an ancillary panel 33 hingedly linked to a top edge of wall 32 by a pair of narrowly-spaced parallel fold lines 34. A suggested distance between the fold lines is at least eight millimeters ({fraction (5/16)}-inch), although a wider distance might work better depending on the type of flute in the corrugated board. Projecting from parallel fold lines 34 is a pair of tabs 35 which are a cover anti-shift means. The function of tabs 35 is explained in a subsequent section.

[0045] In the box format, ancillary panel 33 is disposed approximately parallel to front wall 32 and is held in place by a pair of interlock tabs 36 that engage with a pair of interlock slots 37. Tabs 35 project inward into the box cavity, as shown in FIGS. 2 and 3. Finally, ancillary panel 33 has a pizza-clearing notch 38 disposed along a bottom edge of the panel. The object of notch 38 is to allow a pizza to fit underneath ancillary panel 33 and, thereby, extend all the way to front wall 32. This allows for a box (and blank) to be made with a slightly shorter front-to-back dimension, thereby providing a small savings of material. Further discussion of the function of a pizza-clearing notch can be found in my U.S. Pat. No. 5,806,755 (Product-protecting Pizza Carton).

[0046] Fully-reclinable rear wall 40 is attached to bottom panel rear end edge 24. As used herein, the term “fully-reclinable rear wall” is a rear wall that can recline from a vertical to a horizontal position when the box cover is opened and laid back.

[0047] A pair of thermal-legs 42, which are a carton elevating means, project downward from the bottom edge of wall 40, as illustrated in FIG. 4. As used herein, the term “thermal-leg” is defined as a projection extending downward below the box bottom of a carton. The main object of thermal-legs is to elevate the bottom panel of a carton above a support surface and, thereby, reduce conductive heat transfer through the box bottom to the support surface. Further discussion of the structure and function of thermal-legs can be found in my U.S. Pat. No. 5,833,130 (Multi-function Pizza Carton) and in my patent application Ser. No. 09/061,302 (Designer Pizza Box with Enhancements), that discussion being included herein by reference thereto.

[0048] As shown in FIG. 5, rear wall 40 has an end edge 44 that is disposed at an obtuse angle 46 to the bottom edge of wall 40, the position of that bottom edge being indicated by numeral 24 in the drawings.

[0049] Fall-back side wall structure 50 is an improved variation on a type of fall-back side wall structure disclosed in my U.S. Pat. No. 5,881,948 (Expandable Pizza Box and Method of Use). Structure 50 comprises a side wall 52 attached to bottom panel edge 26, a fall-back corner flap 53 attached to a front end of wall 52, and a verticalizing structure 60 connected to a rear end of wall 52. As used herein, the term “fall-back corner flap” is defined as a flap attached to an end of a side wall and which is of a shape that, when disposed between the panels of an adjacent double-panel wall, can move from a downward position to an upward position and vice versa; and, thereby, can correspondingly allow the side wall to move from a vertical position to a fall-back position and vice versa.

[0050] In the box format, fall-back corner flap 53 is disposed between front wall 32 and ancillary panel 33. Flap 53 has a top edge 54 that angles downward from, or is disposed below, a top edge 55 of wall 52. Because of downward-angling edge 54, fall-back corner flap 53 enables side wall 52 to fall back, or angle outward, when the box is open, as shown in FIG. 3. Further discussion on the structure and function of fall-back corner flaps can be found in my U.S. Pat. No. 5,833,130 (Multi-function Pizza Carton) and in my U.S. Pat. No. 5,881,948 (Expandable Pizza Box and Method of Use).

[0051] Best viewed in FIG. 5, verticalizing structure 60 comprises a diagonal wall 61 attached to a rear end of side wall 52, a free-swinging corner flap 62 attached to a rear end of diagonal wall 61, and a unitary plurality of hingedly connected connector panels comprising connector panels 63aand 63b, which link diagonal wall 61 to rear wall 40. Connector panel 63ais attached to a bottom edge of diagonal wall 61 at a connector edge (and fold line) 64 and to bottom panel 20 at a connector edge (and fold line) 65. Connector panel 63bis attached to panel 63aat a connector edge (and fold line) 67 and to rear wall 40 at a connector edge (and fold line) 44. It is noted that connector edge 44 intersects bottom panel rear end edge 24 and is disposed thereto at obtuse angle 46. It is further noted that connector panel 63bis triangular-shape. Finally, for proper functioning of the carton, the angle between fold lines 67 and 44 is typically about 90 degrees. A recommended angle between fold lines 64 and 65 is 22 degrees.

[0052] Best seen in FIG. 5, verticalizing structure 60 also incorporates a pair of score lines 69ain diagonal wall 61 and a score line 69bin connector panel 63b, which are square-corner-forming means for the carton. Scores lines 69a/bare substantially aligned with rear edge 24. This structural arrangement enables verticalizing structure 60 to be alternately configured into a square corner by “breaking” wall 61 and panel 63balong the axis of score lines 69a/bduring set-up or folding of the box. Operation of this feature is explained in the subsequent section on Operation of the Invention. In place of score lines, short slits or perforations could be used to provide square-corner-forming means. Depiction of square-corner-forming means 69a/bis shown in the drawing of blank 10 but is not shown in the drawings of cartons 12 and 14. However, even though means 69a/bcannot be seen in the carton drawings, it is assumed to be there, nonetheless. Further discussion on the structure and function of square-corner-forming means can be found in my U.S. Pat. No. 5,833,130 (Multi-function Pizza Carton). If there should be no need to create a square corner in the carton, square-corner-forming means 69a/bmight best be omitted.

[0053] In the fully-erected box 12, connector panel 63aoverlies bottom panel 20 and connector panel 63bis upright and disposed at an oblique angle 48 to the bottom panel (see FIGS. 2 and 4).

[0054] In the partially-erected box 14, rear wall 40 is disposed in a reclined position, which typically would be coplanar with bottom panel 20. In addition, diagonal wall 61 and connector panels 63a, 63bmay assume one of two positions. The first position, termed the inward position, is similar to that found in the fully-erected box, whereby diagonal wall 61 is disposed at an obtuse angle to side wall 52 and connector panel 63aoverlies bottom panel 20 and connector panel 63bis upright. The second position, termed the outward position, has diagonal wall 61 coplanar to side wall 52 and connector panels 63a, 63bcoplanar to bottom panel 20, as is shown in FIG. 3.

[0055] Verticalizing structure 60 also serves as a rear corner wall structure of the carton. Therefore, structure 60 is both a verticalizing structure for fall-back side wall structure 50 and a corner wall structure extending between side wall 52 and rear wall 40.

[0056] A cover panel 70 is attached at its rear edge to rear wall 40. It is noted that cover panel 70 has square rear corners. A pair of opposing cover side flap structures 71 are attached to opposing side edges of cover panel 70 and a cover front flap 74 is attached to the front edge. Flap 74 has a pair of opposing flap ends 78. The front edge of cover panel 70 contains forward-projecting tabs 75. In the fully-erected box 12, these tabs overlie the top edge of front wall 32, thereby providing support for cover panel 70. Cover front flap 74 has a height 76 which is less than 80 percent of a height 39 of front wall 32. The shortened height of front flap 74 results in a savings of material. If that's not desired, a full-height cover front flap may be substituted for the shortened-height flap 74.

[0057] The left-to-right length of flap 74 is just slightly less than the distance between tabs 35 which project inward from the top edge of front wall structure 30. This arrangement puts flap ends 78 of cover front flap 74 adjacent to tabs 35 (see FIG. 2). This, in turn, prevents sideways shifting of cover panel 70 during handling of a loaded box and, thereby, reduces the chance of accidental cover opening and provides a rigid feel to the carton. As such, tabs 35 are cover anti-shift means.

[0058] Cover panel 70 also has a pair of score lines 77, called anti-warp flex-lines, disposed in an X-shape configuration. These score lines act to reduce downward warping of the cover panel of a loaded box, particularly when the cover panel is momentarily bent inwardly along the score lines just prior to closing the cover.

[0059] Side flap structure 71 comprises a side flap 72 attached to cover panel 70 and a product anti-slide flap 73 attached to a front end of side flap 72. In the fully-erected box 12, anti-slide flap 73 extends from the side to the front of the box cavity, thereby walling off a front corner space of the box cavity. The object of anti-slide flap 73 is to enable a pizza to be contained on eight sides while maintaining a valuable square corner space for packing an extra item such as a sauce cup along with the pizza. This configuration is illustrated in FIG. 2. Further discussion on the structure and function of anti-slide cover flaps and of anti-warp flex-lines can be found in my U.S. Pat. No. 5,806,755 (Product-protecting Pizza Carton).

[0060] Within the context of this invention, a fold line can be created by a number of means such as, for example, by a crease or score in the board, by a series of aligned spaced short slits in the board, and by a combination of aligned spaced short and long slits. In conclusion, as referred to herein, a fold line is any line between two points on the blank or box along which the board is intended to be folded when the blank is being erected into a box. The type of fold lines shown in the drawings are presently preferred but it will be appreciated that other methods known to those skilled in the art may be used.

[0061] To erect blank 10 into boxes 12 and 14, the following procedure is used. It is noted that this is similar to the procedure that's commonly used for erecting a standard square pizza box having a double-panel front wall. First, simultaneously fold both front corner flaps 53 to upright position and then fold side walls 52 inward or to upright position. Second, fold front wall 32 to upright position and then fold ancillary panel 33 downward until interlock tabs 36 engage with interlock slots 37. At this point, front wall 32 will be in vertical position, side walls 52 will be in fall-back position, and rear wall 40 will be coplanar with bottom panel 20, resulting in partially-erected box 14 (FIG. 3).

[0062] Now you can pursue one of two options: (1) nest the partially-erected box 14 with its outward-angling side walls inside another partially-erected box for use later or (2) finish folding the partially-erected box into fully-erected box 12. To complete the folding of the box, simultaneously push diagonal walls 61 inward, causing them to “flip” into diagonal or inward position. As this is done, rear wall 40 will automatically assume a partially upright position. Pull the cover forward and fold cover side flaps 72 inward so that they slide into the box cavity. During that operation, simultaneously push anti-slide flaps 73 inward so that they also slide into the box cavity. Then push cover front flap 74 downward and close the cover on the box.

[0063] During folding of the fully-erected box, two automatic functions occur. First, as the cover is being closed on the box, cover panel 70 pushes diagonal wall 61 to a downward position which, in turn, automatically pulls side wall 52 from fall-back position to vertical position. Second, as rear wall 40 assumes an upright position, thermal-legs 42 move from a coplanar to a perpendicular position with bottom panel 20, thereby providing an elevating means for holding bottom panel 20 above a support surface such as a table.

[0064] If desired, one or both of the rear diagonal walls 61 can be converted to a square corner prior to closing the box. To accomplish this, put diagonal wall 61 in the outward position, or coplanar with side wall 52. Then grasp wall 61 on opposing sides of score lines 69aand bend the wall so that it “breaks” or folds along the axis of the score lines. Because score lines 69ado not extend all the way across wall 61 it will be necessary to apply some pressure to create the “break” or fold. Once the corner is created, pull cover 70 forward and close it on the box. As this is done, connector panel 63bwill “break” or fold along score line 69b, which is substantially aligned with rear edge 24.

[0065] To “activate” anti-warp flex-lines 77, fold cover panel 70 along each flex-line by bending the panel about 45 degrees along the flex-line. Typically this is done after a pizza has been loaded into the box and while the cover is being closed onto the box. The result of this action is that it causes cover panel 70 to rise up slightly in the center, forming a “crown” to the cover panel.

[0066] I have disclosed a quality-enhancing pizza carton having:

[0067] (a) an improved fall-back side wall structure comprising a side wall, a fall-back corner flap, and a verticalizing structure having a diagonal wall;

[0068] (b) an improved corner wall structure comprising a diagonal wall and a unitary plurality of hingedly connected connector panels, wherein at least one of the connector panels is disposed at an oblique angle to the bottom panel of the box;

[0069] (c) a thermal-leg projecting downward from a rear wall of the box, the box having a straight front wall, first and second side walls adjacent the front wall, and first and second diagonal walls attached to the rear ends of the first and second side walls;

[0070] (d) cover anti-shift means comprising first and second tabs projecting inward from a top edge of a double-panel front wall structure and disposed adjacent the ends of a cover front flap.

[0071] The illustrated number, size, shape, type, and placement of components represent the preferred embodiment; however, many other combinations and configurations are possible within the scope of the invention. Following are of some examples of alternate configurations or modifications upon the invention.

[0072] A first alternate corner wall structure 60a, which is shown in FIG. 6, could be used in place of structure 60. A second alternate corner wall structure 60b, which is shown in FIG. 7, also could be used in place of structure 60. Both are shown in the format of a box blank. In structure 60b, connector panel 63acould be omitted, if desired, thereby creating a third alternate configuration of corner wall structure.

[0073] Also, a modification of the structure of the invention could be created by substituting a shortened-height ancillary panel in place of ancillary panel 33. If this were done, the shortened-height ancillary panel would not interlock into a parallel position with front wall 32 but, instead, be disposed perpendicular to the front wall in the fully-erected box.

[0074] The foregoing discussion has pertained mainly to packaging relatively flat food products such as pizza. However, it should be realized that my invention could be used for other purposes, as well. In conclusion, it is understood that the invention is not to be limited to the disclosed embodiment but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.