Patent Publication Number: US-9850042-B2

Title: Vessel and lid with stacking features

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a divisional application of application Ser. No. 13/754,773, filed Jan. 30, 2013, which in turn claims priority to U.S. Provisional patent application 61/609,142, filed Mar. 9, 2012, and entitled “Lid, and Container System and Lid,” the entire contents of which applications are incorporated herein by this reference. 
    
    
     BACKGROUND 
     Vessels for holding food items may include a separate lid, but are often not provided with an air-tight seal. This is particularly the case for glass vessels for example. Air-tight container-lid systems are typically fabricated from a rigid plastic material, and typically utilize a separate seal member disposed between the lid and container. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Features and advantages of the disclosure will readily be appreciated by persons skilled in the art from the following detailed description when read in conjunction with the drawing wherein: 
         FIG. 1A  is an isometric view of an exemplary embodiment of a container and lid system, in which the container is fabricated of a glass material.  FIGS. 1B and 1C  are respective bottom and end views of the container and lid system of  FIG. 1A . 
         FIG. 2A  is a top view of the container and lid system of  FIG. 1A .  FIGS. 2A and 2C  are respective cross-sectional views taken through lines  2 B- 2 B and  2 C- 2 C of  FIG. 2A .  FIG. 2D  is a top view of an exemplary embodiment of a glass vessel as in the system of  FIG. 1A .  FIG. 2E  is a cross-sectional view taken along line  2 E- 2 E of  FIG. 2D . 
         FIG. 3A  is a top view of an exemplary embodiment of a first shot structure of a lid structure of the system of  FIG. 1A .  FIGS. 3B, 3C and 3D  are respective cross-sectional views taken through lines  3 B- 3 B,  3 C- 3 C and  3 D- 3 D of  FIG. 3A . 
         FIG. 4  is an isometric view of an exemplary embodiment of a second shot structure, a seal structure portion, of the lid structure of  FIG. 1A . 
         FIG. 5A  is a top view of the second shot portion of  FIG. 4 .  FIGS. 5B and 5C  are respective cross-sectional views of the second shot structure of  FIG. 5A . 
         FIG. 6A  is a top view of the lid structure of the system of  FIG. 1A .  FIGS. 6B, 6C and 6D  are respective cross-sectional views taken along lines  6 B- 6 B,  6 C- 6 C and  6 D- 6 D of  FIG. 6A . 
         FIG. 7A  is a side view of a container/lid system as in  FIG. 1A , in which a container is in a stacking relationship to a lower lid.  FIG. 7B  is a cross-sectional view taken along line  7 B- 7 B of  FIG. 7A . 
         FIG. 8A  is an isometric view of an exemplary embodiment of a container and lid system, in which the container is fabricated of a plastic material, and the lid is as described above regarding  FIGS. 2A-7B .  FIGS. 8B and 8C  are respective bottom and front views of the container and lid system of  FIG. 8A . 
         FIG. 9A  is a top view of the container and lid system of  FIG. 8A .  FIGS. 9B  and  9 C are respective cross-sectional views taken through lines  9 B- 9 B and  9 C- 9 C of  FIG. 9A . 
         FIG. 10A  is a side view illustrating a stacking arrangement of a container lid system as in  FIG. 8A , with the container in a stacking arrangement on a lower lid.  FIG. 10B  is a cross-sectional view taken along line  10 B- 10 B of  FIG. 10A . 
         FIG. 11A  is an isometric view of an exemplary embodiment of a set of lids as in the system of  FIG. 1A , in which the lids are in a lid stacking arrangement.  FIG. 11B  is an end view of the stacked lids of  FIG. 11A .  FIG. 11C  is a cross-section view taken along line  11 C- 11 C of  FIG. 11  B. 
         FIG. 12A  is an isometric view of an exemplary embodiment of a set of lids for a circular container configuration, arranged in stacking relation.  FIG. 12B  is a side view of the stacked lids of  FIG. 12A .  FIG. 12C  is a cross-section view of the stacked configuration of  FIG. 12B , taken along line  12 C- 12 C of  FIG. 12B . 
         FIG. 13  is a top view of a plastic vessel.  FIG. 13A  is a cross-sectional view of the vessel of  FIG. 13 , taken along line  13 A- 13 A of  FIG. 13 . 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description and in the several figures of the drawing, like elements are identified with like reference numerals. The figures may not be to scale, and relative feature sizes may be exaggerated for illustrative purposes. 
     In accordance with one aspect, a lid structure with latches is configured for sealing use with container vessels of different materials having differing manufacturing dimensional tolerances, e.g. plastic, metal, glass and ceramic vessels. Plastic vessels can typically be manufactured to tighter tolerances than vessels of other materials such as glass and ceramic. For example, a glass or ceramic vessel may have a flat circumferential seal surface, whose flatness has a certain dimensional tolerance. Plastic or metal vessels can be manufactured with tighter tolerances, so that a similar flat circumferential seal surface can be expected to seal to a lid with greater seal effectiveness than can the glass or ceramic vessel. A lid with capability for use on a plurality of vessel types, i.e. a universal lid, provides significant advantages. For example, the lid may be sold to consumers separately from the vessel, allowing the user to purchase a separately sold vessel to be used with the lid. This provides the consumers with the capability to choose the vessel which best meets his or her needs, while still being able to use the same lid. Another advantage is that the number of types of lids which must be held in inventory by a merchandiser is reduced, since the same lid can be used with multiple types of vessels. Costs of production may be reduced, due to increased scale of production. 
     In accordance with another aspect, a lid configuration is provided with capability of stacking multiple lids together and with interference fitting of the adjacent lids, for maintaining the lid stack in place. 
     Another aspect is a lid and vessel configured to provide the capability of stacking the vessel on top of the lid, with an interference fit of lid features to the base of the vessel. 
     An exemplary embodiment of a vessel-lid combination includes a glass, ceramic, metal or plastic vessel having an open top surrounded by a peripheral edge, a lid fabricated of a plastic material, and a seal structure integrated with the lid to form a unitary structure. The lid is configured to attach to the open top by means of a latch or set of latches integrated with the lid, and the seal structure is configured to provide a substantially air-tight seal between the lid and the peripheral edge of the vessel when the lid is attached to the vessel. In one exemplary embodiment, the vessel is a container fabricated of a glass suitable for baking or oven heating applications. In another embodiment, the vessel is fabricated of a plastic material such as polypropylene. In a general sense the vessel could be any container with a suitable locking lip to engage the lid latches, including plastic, ceramic, metal, glass or other containers. In an exemplary embodiment, a lid is configured for use on different vessels fabricated from dissimilar materials and with different manufacturing tolerances. 
       FIGS. 1A-7B  illustrate an exemplary embodiment of a vessel and lid system  50 , which includes a vessel  60  and a lid  70  with an integral seal structure and latches  80 . The vessel  60  in one embodiment is a glass container, which may be suitable for heating or baking food items in a hot oven. In this embodiment, the vessel  60  is made from a material which can withstand oven temperatures and cooling stresses. Other types of glass, metal, ceramic or plastic vessels can be configured for use with the lid  70 , such that the vessels are formed with a sealing edge and latch engagement lip, as described more fully below. 
     The cross-sectional views of  FIGS. 2B and 2C  illustrate the construction of the exemplary vessel  60  in further detail. The vessel  60  is a unitary structure, having an open top region  60 A, defined by a bottom portion  62 A, a sidewall portion  62 B and a peripheral rim portion  64 . A sealing edge portion  62 C is defined by the sidewall portion at or adjacent the open top region. In this example, the sidewall portion  62 B is angled outwardly from the bottom region, defining a 13.5 degree angle relative to the bottom portion. This particular angular arrangement is but one example, other configurations of the sidewall and bottom portions of the vessel may alternately be employed. The rim portion  64  includes a generally flat top edge portion  64 A and a latch engagement lip portion  64 B. 
     The lid  70  is attached to the vessel  60  and latched in place to cover the open vessel top, using latches  80  connected by living hinges to the lid proper on opposite sides of the lid. The latches have latch hook features  82 A which engage the latch engagement lip portion  64 B of the vessel when the lid is placed on the vessel and the latches rotated about the hinges to the latched position shown in  FIGS. 1A and 2B , for example. A seal structure  90 , discussed more fully below, engages a seal surface on the vessel, the top edge portion  64 A, as the lid is latched in place. 
     The lid  70  in an exemplary embodiment is fabricated by injection molding using a two shot molding technique, in which a first shot structure is fabricated of a first plastic material, and then the lid structure is completed in a second shot in which a second plastic material is overmolded to a portion of the first shot structure to form the seal structure  90 . The second plastic material is bonded to surfaces of the first shot material as a result of the molding process.  FIGS. 3A-3D  illustrate an exemplary embodiment of the first shot structure  70 - 1  of the lid  70 . In an exemplary embodiment, the primary, first shot lid structure is formed from a polymer such as polypropylene or similar structurally rigid polymer material.  FIG. 3D  also illustrates that the latch  80  in the downward, latched condition, is recessed relative to the lid outer skirt, so that the latch and hinge do not protrude outwardly from the lid skirt, thus offering some protection against damage to the latch. 
       FIGS. 4 and 5A-5C  illustrate an exemplary embodiment of the second shot structure, the seal structure  90 , in isolation. An exemplary over-mold material used in the second shot is a thermoplastic elastomer (TPE) material. By fabricating the seal structure in this manner using an overmold, second shot process, several advantages are obtained, including lower cost relative to a separate, removable seal, cleanliness (by avoiding space between a removable seal and the lid structure), and ease of use since the seal structure is permanently attached to the first shot structure. 
       FIGS. 6A-6D  illustrate an exemplary embodiment of the lid  70  in a completed form, i.e. after the overmolding process is completed to form the second plastic material to the first shot structure and define the seal structure  90 . In an exemplary embodiment, the first shot lid structure defines a peripheral channel  72 - 1  between a peripheral downwardly extending skirt portion  72 - 3  and an inner peripheral wall structure  72 - 2 , connected by a web portion  72 - 4 . The second shot material of the seal structure  90  in this embodiment is molded to the interior side wall  72 - 3 A ( FIG. 3B ) of the skirt portion and to the web portion. In an exemplary embodiment, the second shot material does not fill the channel, but in other embodiments, the second shot material may fill a larger part or all the channel if desired for a particular application. 
     The seal structure  90  in this embodiment comprises several portions. A main body portion  90 C is attached to the inner wall of the skirt and to the web portion. Another seal portion is a protruding spring portion  90 B. Another seal portion is compression portion  90 A. For use with glass vessels, a feature is that the seal structure is configured to absorb the greater flatness variability in the sealing area or surface of the glass vessel. The spring portion  90 B of the seal structure is configured to flex easily to absorb the variability of the vessel seal surface, while the compression portion  90 A extends below the skirt portion by a sufficient distance to compress in response to latch closure and provide adequate latch retention force to hold the lid latches in the closed position. The flexing of the spring portion is illustrated in  FIGS. 2B and 2C , in the case of a glass vessel  60  with the lid  70 .  FIGS. 9B and 9C  illustrate a plastic vessel with the lid  70 . 
     In an exemplary embodiment, the spring seal portion  90 B is a finger-like protrusion, angled inwardly toward the interior portion of the lid. In other embodiments, the spring seal portion may be angled outwardly, away from the lid interior. Other suitable configurations for the spring portion may be employed, such as a rib downwardly extending from the compression portion, or an elbow-shaped cross-section configuration. Exemplary dimensions of the spring portion for one embodiment are a height dimension on the order of 0.04 to 0.05 inch, and a thickness of 0.025 to 0.040 inch. Exemplary dimensions for the compression portion are a thickness of about 0.10 inch and a height varying from about 0.085 to 0.15 inch, depending on the location around the perimeter. An exemplary overall height dimension for the seal structure is 0.35 inch, for an exemplary embodiment. 
       FIGS. 8A-10B  illustrate another vessel and lid system  50 - 1 , in which the lid  70  is used in combination with a plastic vessel  60 - 1 . The vessel  60 - 1  is a unitary structure, having an open top region  60 - 1 - 1 A, defined by a bottom portion  60 - 1 - 2 A, a sidewall portion  60 - 1 - 2 B and a peripheral rim portion  60 - 1 - 4 . In this example, the sidewall portion  60 - 1 - 2 B is angled outwardly from the bottom region, defining an 8 degree angle relative to the bottom portion, which is typically variable for different vessel sizes and configurations. This particular angular arrangement is but one example, other configurations of the sidewall and bottom portions of the vessel may alternately be employed. The rim portion  60 - 1 - 4  includes a generally flat top edge portion  60 - 1 - 4 A and a latch engagement lip portion  60 - 1 - 4 B. 
     The lid latching and sealing structures interact with the vessel  60 - 1  in a manner similar to that described above regarding the glass vessel  60 . The flat top edge portion  60 - 1 - 4 A of the plastic vessel may be flatter than the corresponding seal surface of the glass vessel. 
     Another feature of a lid and vessel combination is the provision of a lid receptacle feature, configured to capture the base of a vessel in a stacking arrangement, without utilization of special features on the vessel base. The stacking is illustrated in  FIGS. 7A and 7B  for a glass vessel  60 , and in  FIGS. 10A-10B  for a plastic vessel  60 - 1 . 
     The receptacle feature of the lid  70  is illustrated, for example, in  FIGS. 3A-3C . The inner wall  72 - 2  and lid web portion  72 - 5  connected to the inner wall define a recess or receptacle region  76 . The receptacle region has a depth D 3 . The top edge  72 - 2 A of the inner wall  72 - 2  defines a closed generally rectangular periphery P ( FIG. 3A ). However, the periphery P in the areas intermediate the lid corners is defined by length dimension D 1  and width dimension D 2  which are somewhat smaller than the same length dimension measured at the corners of the lid. The inner wall  72 - 2  may be vertical or inclined inwardly at the intermediate regions. The dimensions D 1  and D 2  are selected in combination with the dimensions of the base of vessels such as  60  and  60 - 1 . In the case of glass or ceramic vessels, the lid is designed with enough clearance to allow the glass vessel (such as vessel  60 ) to enter and sit in the receptacle without interference. In the case of a plastic vessel, such as vessel  60 - 1 , the lid is designed to create an interference fit between the periphery P and the side walls of the vessel when the vessel is placed over the receptacle  76  and pressed down into the receptacle. In the case of a plastic vessel, both the vessel base and the lid wall may flex sufficiently to allow the vessel base to be seated in the receptacle  76 . 
     This lid-vessel stacking may be employed to stack two or more of the vessel-lid systems while securely preventing lateral movement of an upper system relative to a lower system. Moreover, this can be achieved without special features in the base of the vessel. The vessel walls adjacent the base may be vertical or closer to vertical in the areas of interference with the lid, and with the angle relative to vertical increasing above the areas of interference. 
     Another feature of an embodiment of the lid  70  is the capability of lid nesting of multiple lids with interference fit between adjacent lids to lock the lids together.  FIGS. 11A-11C  illustrate two lids  70  stacked together. The outer skirt  72 - 3  of the lid  70  in the lid corners has a step or shoulder  72 - 3 A, such that the lower portion  72 - 3 B below the shoulder can be fitted over the outer skirt of another lid  70  and rest on the shoulder  72 - 3 A of a lower lid in the stack.  FIGS. 3C and 6C  show the construction of the lid skirt in the corner regions. The skirt dimensions are selected such that there is an interference fit between the interior wall surface of skirt portion  72 - 3 B and the outer wall surface of the skirt above the shoulder of a nested lid  70 , to provide a frictional engagement between the respective lids. The interference dimension may be on the order of 0.010 inch for one exemplary embodiment, but the interference dimension may be different for other embodiments and applications. The interference may secure the lids in the nested configuration, thereby enhancing storage and shipping of lids. 
     While the exemplary embodiments of the lids and vessels have heretofore been described with respect to rectangular configurations, the features and aspects may be utilized with other configurations. For example,  FIGS. 12A-12C  illustrate two nested lids designed to fit vessels having a circular footprint configuration. 
     The lid  70  is designed for sealing attachment to vessels with a range of dimensional tolerances. The vessel rim as noted above includes a generally flat top rim surface, for example  64  ( FIG. 2E ). The top rim surface may be designed with a downward sloping outer edge portion  64 A 2 . The inner edge portion  64 A 1  is preferably flat. Thus, moving away from the center of the lid, there is a downward slope of the surface  64 A. This downward slope accommodates some misalignment of the lid to the vessel, and also some vessel tolerances, in regard to latching force. The latching force is determined by how much the seal compresses when the latches are closed. If the position of the latch hinge on the lid moves outwardly relative to the vessel rim, this would tend to increase the distance from the hinge to the vessel latch surface, and hence the latching force. However, the slope of the rim surface on the outer part of the rim allows the lid to move downwardly, so that the distance from the hinge to the vessel latch surface remains the same, or at least reducing an increase in this distance. The slope or curvature thus tends to reduce variations in the latching force due to vessel dimensional tolerances. 
     In another embodiment, the sealing surface at the rim of the vessel may be designed with a slight slope downwardly from the center of the sealing surface toward the center of the lid, as well as a slight slope downwardly in a direction away from the lid center. This embodiment can accomplish the same benefit in reducing variations in latching force whether the lid periphery is shifted inwardly or outwardly, either as a result of misalignment or manufacturing tolerances.  FIGS. 13 and 13A  illustrate this feature, in relation to a plastic vessel  60 - 1 ′ with top rim  60 - 1 - 4 ′ and sealing surface  60 - 1 - 4 ′. Here, the midpoint of the sealing surface is the highest point of the surface relative to the vessel base, and the sealing surface slopes downwardly in either direction from the midpoint. 
     Although the foregoing has been a description and illustration of specific embodiments, various modifications and changes thereto can be made by persons skilled in the art without departing from the scope and spirit of the invention.