Abstract:
A thermoformed container system with a tray and a lid mounted on the tray, that includes special structures to help two or more containers to stand on their bottom edges when nested together, even though each individual container would be too unstable to stand in isolation. Alternative embodiments of the invention include a product case pack comprising at least two containers with product inside each container, and a method of retail sales display of two or more containers, where the containers are adapted to stand on their bottom edges when nested together.

Description:
FIELD OF THE INVENTION 
     This invention relates generally to the field of containers. More particularly, the present invention relates to thermoformed containers having features that enhance the container&#39;s ability to stand erect when multiple containers are displayed together for sale. 
     BACKGROUND OF THE INVENTION 
     Sales and display space in a store is a valuable resource, especially in high traffic areas such as end caps or in expensive refrigerated shelving in the meat or dairy department of a grocery store. Effective utilization of the available sales and display space in a store can make the difference between profit and loss, when that space is used to maximize planned or impulse purchases, to provide for the right levels of inventory, and to offer a wider variety of product choices. 
     In a retail sales environment, product containers often have an appearance meant to attract the attention of consumers, and they often bear information and messages meant to motivate consumers to make a purchase. It follows that the greater the usable display area available on the surface of a particular product container, the larger the billboard on which to display an attractive appearance and convey messages to potential purchasers. Consequently, all other things being equal, a container with more usable display space would be preferred over a container with less usable display space on its surface. 
     Another practical problem in a retail environment is to maintain the right amount of inventory to meet demand. Too much space allocated to inventory of one particular product is undesirable when that space could be better used to offer a wider variety of products, or when that inventory is not turning over quickly enough. Too little space for inventory of one particular product is undesirable if it results in lost sales when a product is out of stock, or if the lack of space requires too-frequent inventory replenishment. Consequently, a container that allows more of a particular product to be stored in a given volume of sales and display space would be preferred over a container that makes less efficient use of that space, especially when that space is at a premium. 
     Thermoformed plastic containers are well known as inexpensive and highly customizable containers for the sale of a wide variety of products, everything from cell phones to deli meats. Thermoformed plastic containers are typically transparent and rigid, so they can give a consumer the ability to examine a product closely. They can be made tamper-resistant, to reduce the risk that the product could be damaged or contaminated. They are typically lightweight, and can be efficiently stored or shipped together in a nested fashion. It is easy to include product information and cosmetic features in these types of containers, for example with stickers or cards glued to the outside of the containers, with embossing molded into the containers, or with paper inserts inside the containers. 
     For these and other reasons, thermoformed plastic containers are often preferred over other available options for product containers, such as cardboard or metal boxes, bags, metal cans, or paper cartons. However, for some packaging applications, for example sales of products in refrigerated deli meat sections of a grocery store, thermoformed plastic containers have not gained market share compared to these other available options. What is needed is a thermoformed container system that can stand up to maximize usable available display space on its surface and that can nest together to maximize storage density of inventory in a given volume of sales and display space. 
     SUMMARY OF THE INVENTION 
     A first embodiment of the invention is a thermoformed container system using thermoformed plastic containers, each container having a tray and a lid mounted on the tray. The tray and lid include special structures to help two or more containers to stand on their bottom edges when nested together, even though each individual container would be too unstable to stand in isolation. In a container system according to this first embodiment of the invention, when two or more containers are nested together with the lid of the rearward container coupled with the tray of the forward container, a first engagement structure on the tray in front exerts a downward force met with an equal but opposite upward force from a second engagement structure on the lid behind it, resulting in an equilibrium of forces that helps the two or more nested containers to prop themselves up and stand vertically on their bottom edges. 
     A second embodiment of the invention is a product case pack comprising at least two containers, each container including a tray and a lid mounted on the tray, and with some kind of product inside the container. The containers are adapted to be nested together, with the lid of the rearward container nested with the tray of the forward container. The containers include a first engagement structure on the tray and a second engagement structure on the lid, wherein the first engagement structure on the forward tray exerts a downward force met by an upward force from the second engagement structure on the lid behind it when the nested containers are positioned together to stand vertically on their bottom edges. 
     A third embodiment of the invention is a retail sales display method comprising providing a sales and display space having a shelf area, providing at least two containers, each having a tray, a lid mounted on the tray, and some kind of product inside, wherein the containers include a first engagement structure on the tray and a second engagement structure on the lid, nesting the containers together with the lid of the rearward container coupled with the tray of the forward container, and positioning the containers to stand vertically on their bottom edges, whereby the first engagement structure on the forward tray can exert a downward force met by an upward force from the second engagement structure on the rearward lid to enhance the stability of the plurality of containers standing together. 
     Further objects, features, and advantages of the invention will be apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1A  is a perspective view of a tray for a container according to the invention; 
         FIGS. 1B ,  1 C,  1 D,  1 E, and  1 F are bottom, lateral, top, cavity, and rear side views, respectively, of the tray of  FIG. 1A ; 
         FIGS. 2A and 2B  are cross-sections of the tray at lines  2 A- 2 A and  2 B- 2 B, respectively, in  FIG. 1A ; 
         FIG. 3A  is a perspective view of a lid for a container according to the invention; 
         FIGS. 3B ,  3 C,  3 D,  3 E,  3 F, and  3 G are bottom, first lateral, second lateral, top, external (display) and internal (cavity) side views, respectively, of the lid of  FIG. 3A ; 
         FIGS. 4A and 4B  are cross-sections of the lid at lines  4 A- 4 A and  4 B- 4 B, respectively, in  FIG. 3A ; 
         FIG. 5  is a perspective view of a container according to the invention comprising the lid of  FIG. 3A  on the tray of  FIG. 1A ; 
         FIG. 6  is a cross-section of the container at line  6 - 6  in  FIG. 5 ; 
         FIG. 7  is a perspective view of three containers according to the invention, nested together and standing in a sales and display area, for example on a refrigerated shelf in a grocery store; 
         FIG. 8A  is a side view of the three containers of  FIG. 7  taken at line  8 A- 8 A in  FIG. 7 ; 
         FIGS. 8B and 8C  are cross-sections of the three containers of  FIG. 7  at lines  8 B- 8 B and  8 C- 8 C, respectively, in  FIG. 7 ; and 
         FIG. 9  is a side view of a unitary embodiment of a container according to the invention which includes a hinge connecting the lid to the tray. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 1A-1F  provide various views of an exemplary tray  20  for a container according to the invention. For purposes of illustration and not as a limitation, the names of the walls of the tray  20  (e.g. top, side, bottom, rear, etc.) assume that the tray  20  is positioned in an upright standing position with the cavity side of the tray facing the observer and with the bottom wall  22  (the wall labeled “BRAND” in  FIG. 1A ) facing down. 
     In other words, the names assume the tray  20  is viewed as in  FIG. 7 . In that orientation, the tray  20  can be said to include a bottom wall  22 , two side walls  28 , a top wall  30 , and a rear wall  32  that surround an interior cavity  36 . 
     The tray  20  includes a first engagement structure  26 . In the exemplary tray  20 , the first engagement structure  26  is located on the bottom rear corner  24  where the rear wall  32  and bottom wall  22  meet. However, this particular location is not required and the first engagement structure  26  could be located somewhere else, for example a side wall  28  or rear wall  32 .  FIGS. 1A ,  1 B,  1 F,  2 A, and  8 C perhaps best illustrate the exemplary first engagement structure  26 . 
     In the exemplary tray  20 , the first engagement structure  26  is an inverted shelf with a rib or ridge, convex when viewed from outside the tray  20 , that protrudes generally downwardly from the bottom rear corner  24  when the tray  20  is positioned with its bottom wall  22  facing down, as perhaps best shown in  FIGS. 2A and 8C . However, this exact structure is not required and the first engagement structure could be a different structure, for example with another male or convex structure such as a post, pin, plug, bulge, bump, hump, pyramid, cube, nub, projection, protrusion, protuberance, knob, or a combination of these structures. Alternatively or in combination, the first engagement structure could include a complementary structure, for example a concave (female) structure such as a slot, channel, socket, hole, notch, pit, crater, dent, depression, impression, gap, hollow, pit, or pocket. 
     The rear wall  32  forms the bottom of the interior cavity  36 , and may include one or more perimeter channels  34 . Any of the walls may include one or more embossed wall features  38  for decoration or for structural purposes. 
     Any of the walls may also include one or more raised engravings  42 , for example brand markings, informational messages, or decorations. The engravings  42  can be placed inside a frame  40  that preferably has a convex shape extends slightly outwardly from the wall on which it appears, creating a space behind the engraving  42 . When two trays are nested together for storage or transport, engravings  42  on the top tray can extend into the space created behind the convex framed area  40  on the bottom tray, reducing the interference between the engravings  42  on the top tray and the inner sidewall of the bottom tray. 
     The bottom wall  22 , side walls  28 , and top wall  30  all terminate in a cavity rim  44  that forms the periphery of the interior cavity  36 . As perhaps best shown in the cross-sections of  FIGS. 2A and 2B , the cavity rim  44  includes an inside wall  46 , a top surface  50 , and an outside wall  52 . The cavity rim  44  is preferably formed to include an inside wall taper  48  and outside wall taper  54  for mating with a corresponding taper on a lid, to improve the seal between the tray  20  and its lid. The rim  44  may also include an outside flange  56 . 
     The exemplary tray  20  can have an interior cavity  36  that is about 1.5 inches deep from the top surface  50  of the rim  44  to the rear wall  22  that forms the bottom of the cavity  36 . The tray  20  can be about 8 inches wide, from one side wall  28  to the other side wall  28 , when the tray is positioned to stand vertically as in  FIG. 7 . The tray  20  can be about 5.5 inches tall, from the highest point above the top wall  30  to the bottom edge below the bottom wall  22 , when the tray is positioned to stand vertically as in  FIG. 7 . However these exact dimensions are not required—the tray could be bigger or smaller, and/or could have different relative dimensions. 
       FIGS. 3A-3G  provide various views of an exemplary lid  60  for a container according to the invention. For purposes of illustration, the names of the portions of the lid  60  (e.g. top, side, bottom, etc.) assume that the lid  60  is positioned to cover the cavity of a tray  20  in an upright standing position with the cavity of the tray facing the observer, in other words as shown in  FIG. 7 . 
     The lid  60  includes a central portion  62  surrounded by a bottom edge  82 , two side edges  86 , and a top edge  88 . The central portion  62  may include engravings  64 , such as brand markings, informational messages, or decorations. The lid  60  has an exterior surface  66  that faces outwardly when the lid  60  is fitted on a tray  20 , and an interior surface  70  that faces the interior cavity  36  of the tray  20 . 
     The bottom edge  82 , two side edges  86 , and top edge  88  form a perimeter sealing rim  72  that is shaped to mate with a complementary cavity rim  44  on a tray  20 . As perhaps best seen in the cross-sections of  FIGS. 4A and 4B , the perimeter sealing rim  72  includes a sealing slot  74  with an inside wall  76  and an outside wall  78 . The perimeter sealing rim  72  may include a flange  80  extending outwardly from the outside wall  78 . The lid  60  may include a removal tab  90  to facilitate removal of the lid  60  when it is mounted on a tray  20 . The removal tab  90  can be placed on either side of the lid, preferably on a corner of the lid between the bottom edge  82  and a side edge  86 . 
     The lid  60  includes a second engagement structure  84  that is configured to mate with the first engagement feature  26  of the tray  20 , as perhaps best shown in  FIG. 8C . In the exemplary lid  60 , the second engagement structure  84  is located where the inside wall  76  of the sealing rim  72  meets the central portion of the lid  60 , at a point near the bottom edge  82  of the lid. However, this particular location is not required and the second engagement structure could be located somewhere else, for example near a side edge  86  or central portion  60 .  FIGS. 3A ,  3 F,  4 A, and  8 C perhaps best illustrate the exemplary second engagement structure  84 . 
     In the exemplary lid  60 , the second engagement structure  84  is a shelf or prop with a slot or notch, concave when viewing the exterior side  66  of the lid  60 , that opens generally upwardly in the inside wall  76  of the sealing rim, when the lid  60  is positioned with its bottom edge  82  down, as perhaps best shown in  FIGS. 4A and 8C . However, this exact structure is not required and other complementary engagement structures could be used. For example, the second engagement structure could be a shelf or prop, or could include a different female or concave structure, such as a channel, socket, hole, notch, pit, crater, dent, depression, impression, gap, hollow, pit, or pocket. Alternatively or in combination, the second engagement structure could also include a complementary structure, for example a convex (male) structure such as a post, pin, plug, bulge, bump, hump, pyramid, cube, nub, projection, protrusion, protuberance, knob, or a combination of these structures. 
     The exemplary lid  60  is preferably sized to fit the tray  20 . Like the tray  20 , the lid  60  can be about 8 inches wide, from one side edge  86  to the other side edge  86 , when the lid is positioned to stand vertically as in  FIG. 7 . Like the tray  20 , the lid  60  can be about 5.5 inches tall, from the top edge  88  to the bottom edge  82 . However, as with the tray, these exact dimensions are not required—the lid could be bigger or smaller, and/or could have different relative dimensions. 
       FIG. 5  is a perspective view of a container according to the invention comprising the lid  60  on the tray  20 . The seal between the lid  60  and tray  20  is best illustrated in the cross-section view of  FIG. 6 , taken at line  6 - 6  in  FIG. 5 . As shown in  FIG. 6 , the inside wall  76  and outside wall  78  are preferably formed so that the sealing slot  74  on the lid has a tapered section that fits a matching tapered section on cavity rim  44  on the tray  20 . This provides an interference fit that tends to keep the lid sealed on the tray unless deliberately opened by the consumer. The serpentine path through the seal between the lid and tray also helps to make the seal liquid-tight. 
       FIGS. 7 and 8A  show a plurality of containers according to the invention, nested together and standing in a sales and display area  100  in a store, for example holding contents  102  (not shown in  FIG. 7 ). If the contents  102  are deli meat products, the sales and display area  100  might be a refrigerated shelf. The exemplary plurality of containers includes three containers, a front container  10 , a middle container  110 , and a rear container  210 . However, it should be understood that the plurality of nested containers could include a greater number of containers, or as few as two containers. 
     As perhaps best shown in the cross-section of  FIG. 8C , the front container  10  and middle container  110  are nested together with the first engagement structure  26  of the tray  20  of the front container  10  mated with the second engagement structure  84  of the lid  60  of the middle container  110 . The middle container  110  is nested together with the rear container  210 . 
     It can be seen that any of the individual containers  10 ,  110 , or  210  would not be stable if positioned in isolation to stand with the bottom wall  22  of the tray facing down and with the bottom edge of the container resting on a sales and display surface  100 . For the same reason that a chair with only two legs cannot stand, a container  10  positioned as in  FIG. 8C  but in isolation (without containers  110  or  210 ) would tend to rotate in a clockwise direction about the pivot point formed by the bottom edge of the container and fall over onto the rear wall of the container. 
     In the exemplary containers  10 ,  110 , and  210 , the bottom edge of the container is formed by the outside wall flange  80  of the perimeter sealing rim  72  of the lid  60  at a point near the bottom edge  82  of the lid  60 , together with the outside wall flange  56  of the cavity rim  44  of the tray  20  near the bottom wall  22  of the tray  20 . However, this particular structure is not required and the bottom edge of the container could be formed in another way, for example by the cavity rim  44  of the tray and sealing rim  72  of the lid without any flanges or by a hinge  106  in a unitary package as shown in  FIG. 9 . 
     While the container  10  would be generally unstable When positioned to stand on its bottom edge in isolation, two or more containers nested together can stand on their bottom edges when they are engaged together, as perhaps best shown in  FIG. 8C . Although the container  10  still tends to rotate in a clockwise fashion about its bottom edge, this rotation exerts a downward force on the first engagement structure  26  of container  10 , where it is met by an equal and opposite upward force from the second engagement structure  84  of container  110  resulting in an equilibrium of forces that makes the nested containers more stable. This same basic principle of operation does not depend on the specific structures (male vs. female, etc.) used for the first engagement structure  26  and second engagement structure  84 . Other functional structures, such as the alternatives discussed above with respect to first engagement structure  26  and second engagement structure  84 , could be used to achieve the same result in the same way. 
     Nested together and engaged as shown in FIGS.  7  and  8 A- 8 C, container  10  and  110  can stand on their edges with their bottom walls  22  facing down. In this orientation, the largest side of the containers, the exterior face  66  of the lid, is positioned to face the consumer. This maximizes the display area available no matter how many containers are in inventory. A configuration with more than two containers nested together, for example with containers  10 ,  110 , and  210  nested together, works in basically the same way and can be even more stable. 
     While the preceding discussion of the exemplary container  10  uses particular embodiments of a tray  20  and lid  60 , the invention could be practiced with other tray and lid configurations. The exemplary container  10  includes a single internal cavity  36 , but this particular structure is not required. For example, a different number of cavities could be provided for particular applications, and the container as a whole or the individual cavities could be different sizes and/or shapes. 
     The tray  20  and lid  60  of the container  10  are preferably made using thermoforming methods, from a suitable thermoformable material. For example, a tray  20  and lid  60  meant for use with ready-to-eat foods might be formed of a thermoformable plastic such as oriented polystyrene (OPS), talc-filled polypropylene (TFPP), polypropylene (PP), high impact polystyrene (HIPS), polyethylene terepthalate (PET), amorphous PET (APET), crystalline polyethylene (CPET) polystyrene copolymer blends, styrene block copolymer blends, and the like. 
     The materials forming the tray  20  and lid  60  may be different, and those materials are not necessarily homogeneous, but may be, for example, a laminate, co-extruded material, or multilayer material. Additional components could be used, for example a plastic or foil membrane could be positioned on the tray  20  and covering the contents  102  in a way that allows the lid  60  to be fastened on the tray. 
     It is understood that the invention is not confined to the embodiments set forth herein as illustrative, but embraces all such forms thereof that come within the scope of the following claims.