Abstract:
A lid for a cup includes an annular wall with a top rim and a bottom base. The annular wall is insertable substantially in its entirety into a cup wherein an exterior face of the annular wall produces a compressive force against an interior face of the cup sufficient to create a seal along a continuous path circumscribing the interior face of the annular wall of the cup. A surface extends from an interior face of the annular wall and the surface covers an area circumscribed by the annular wall. The surface has a dispensing orifice therein.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates generally to a lid for a disposable container. 
       BACKGROUND 
       [0002]    A dispensing container is typically formed with a cup and a lid that attaches to the rim of the cup. After putting a liquid into the cup, the lid is attached to form a sealed container that resists spillage. The lid typically has an orifice of sufficient area to dispense a product. The orifice is large enough to dispense the product based on the viscosity of the product and consumer preference for product flow rate, yet small enough to reduce spillage from tilting or bumping the container. Common examples of a dispensed liquid product are coffee, tea or a cold beverage. 
         [0003]    A lid commonly has a concaved lip that attaches to the cup with a compressive force on the rim. The lid is typically made of plastic with sufficient elasticity to maintain the compressive force on the rim when attached to the cup. 
         [0004]    When the consumer subsequently disposes of the container, the lid is not always removed. When the cup and lid are made from materials from different recycling categories, the container may be rejected for recycling. For example, glass, plastic and paper are a few of the numerous recycling categories. A container composed of a paper cup and a plastic lid may require the lid to be separated prior to recycling. 
       SUMMARY 
       [0005]    In one aspect, the invention features a lid for a cup. The lid has an annular wall with a top rim and a bottom base. The annular wall is insertable substantially in its entirety into a cup wherein an exterior face of the annular wall produces a compressive force against an interior face of the cup sufficient to create a seal along a continuous path circumscribing the interior face of the annular wall of the cup. A surface extends from an interior face of the annular wall and the surface covers an area circumscribed by the annular wall. The surface has a dispensing orifice therein. 
         [0006]    In another aspect, the invention features a lid for a cup. The lid has an annular wall with a top rim and a bottom base. The annular wall is insertable substantially in its entirety into a cup wherein an exterior face of the annular wall produces a compressive force against an interior face of the cup sufficient to create a seal along a continuous path circumscribing the interior face of the annular wall of the cup. The annular wall of the lid has a constant height. The annular wall of the lid has a taper with the diameter of the top rim being larger than the diameter of the bottom base. The top rim of the lid forms a concave lip for resting on a rim of the cup. A surface extends from an interior face of the annular wall and the surface covers an area circumscribed by the annular wall. The surface has a dispensing orifice therein. 
         [0007]    In another aspect, the invention features a container with a cup having a tapered annular wall and a lid having an annular wall. The annular wall of the lid has a top rim and a bottom base. The annular wall of the lid is insertable substantially in its entirety into the cup such that an exterior face of the annular wall of the lid produces a compressive force against an interior face of the annular wall of the cup sufficient to create a seal along a continuous path circumscribing the interior face of the annular wall of the cup. A surface extends from an interior face of the annular wall of the lid and the surface covers an area circumscribed by the annular wall of the lid. The surface has a dispensing orifice therein. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The above and further advantages of this invention may be better understood by referring to the following description in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in various figures. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. 
           [0009]      FIG. 1  is an exploded three-dimensional view of a container showing an embodiment of a lid and a cup. 
           [0010]      FIG. 2  is a three-dimensional view of a container showing the lid inserted into the cup. 
           [0011]      FIG. 3A  is a schematic three-dimensional view of the lid of  FIG. 1  with a lip. 
           [0012]      FIG. 3B  is a schematic cross-sectional view of  FIG. 3A  taken along line A-A′ showing annular walls with a taper. 
           [0013]      FIG. 3C  is a schematic cross-sectional view of the lid similar to that shown in  FIG. 3B , further modified by showing annular walls without a taper. 
           [0014]      FIG. 4  is a cross-sectional view of the container showing an example of a path representative of a seal that may form between the lid as shown in  FIG. 3A  and the cup. 
           [0015]      FIG. 5A  is a schematic three-dimensional view of an embodiment of a lid without a lip. 
           [0016]      FIG. 5B  is a schematic cross-sectional view of the lid of  FIG. 5A  taken along line A-A′ showing annular walls with a taper. 
           [0017]      FIG. 5C  is a schematic cross-sectional view of the lid similar to that shown in  FIG. 5B , further modified by showing annular walls without a taper. 
           [0018]      FIG. 6  is a cross-sectional view of the container showing an example of a path representative of a seal that may form between the lid as show in  FIG. 5A  and the cup. 
           [0019]      FIG. 7A  is a schematic cross-sectional view of an embodiment of a lid with a lip, annular walls without a taper and a surface wherein the top wall section is the entire annular wall. 
           [0020]      FIG. 7B  is a schematic cross-sectional view of  FIG. 7A  taken along line A-A′. 
           [0021]      FIG. 7C  is a schematic cross-sectional view of the lid similar to that shown in  FIG. 7B , further modified with the lip removed. 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    Embodiments of lids described herein include variations that form a seal between the lid and the interior wall of a cup rather than gripping the top rim of the cup. The embodiments describe lids that are inserted into a cup with a bottom base of the lid narrower than the opening of the cup. The lid is inserted until a sufficient portion of the wall of the lid makes contact with the inside of the cup to form a continuous seal within the interior of the cup. The lid is then further inserted into the cup to create compressive force between the lid and the interior of the cup. The compressive force forms a seal to contain product within the cup and retains the lid with frictional force relative to the inside of the cup such that the lid is prevented from being accidentally dislodged. The inserted lid forms a container that holds a product, which may be a liquid, a granular form solid or other suitably dispensable product. In contrast to lids known in the art, the various embodiments of a lid as described do not exert significant, if any, force on the outer wall of the cup when forming the seal. Some embodiments of lids have a concave lip on the top rim of the lid to prevent the lid from being inserted too far into the cup. Insertion is limited to the point where the lip of the lid rests on the top rim of the cup. Further variations include a non-tapered wall of the lid and different positions of a surface that retains the product in the container against accidental spillage. Advantageously, the lid can be made of the same material as the cup. In addition, the lid can be manufactured using a variety of existing manufacturing processes. The result is a lid that may remain affixed to the cup after use, thereby facilitating the recycling process. Common examples of readily recyclable materials include paper, plastic and STYROFOAM™. These examples illustrate a few of the numerous recyclable materials that exist, or may be envisioned in the future. The embodiments described will provide the benefits of simplified recycling for any lid material that is sufficiently similar to the cup material such that the lid and cup materials are considered from the same recycling category. 
         [0023]      FIG. 1  shows an embodiment of a dispensing container  10  with a tapered cup  20  positioned to receive one embodiment of a lid  30 .  FIG. 2  shows the dispensing container  10  with the lid  30  inserted into the cup  20 , thereby forming a seal between the cup  20  and the lid  30 . The seal operates to limit accidental spillage of a product previously introduced into the cup  20 . The lid  30  has a concave lip  31  that limits the extent to which the lid can enter the cup  20  by making contact with, and resting upon, a cup rim  22 . 
         [0024]      FIG. 3A  shows one embodiment of the lid  30 .  FIG. 3B  further illustrates the embodiment of the lid  30  including an annular wall  32  with a top rim  34  (having the concave lip  31 ) and a bottom base  36 . The annular wall  32  is tapered at an angle substantially similar to the wall of the cup  20 . Tapered, as used herein, means that the diameter of the top rim  34  is greater than the diameter of the bottom base  36 . The annular wall  32  is divided into a top wall section  38  and a bottom wall section  40  by a surface  42 . The bottom wall section  40  is thicker than the top wall section  38  and the bottom wall section  40  is similar to the thickness of the surface  42 . The surface  42  has a dispensing orifice  44  and a venting orifice  46 . In general, the dispensing orifice is larger than the venting orifice. The dispensing orifice must have sufficient area to dispense a product at a flow rate acceptable to customers without being unduly large such that the risk of accidental spillage through the orifice is significantly increased. The venting orifice allows air to flow into the container to replace the dispensed product. This reduces the vacuum pressure caused by a reduction in product volume. The reduction in vacuum pressure permits faster product flow rate out of the dispensing orifice. 
         [0025]    Exemplary dimensions of the lid  30  are shown in  FIG. 3B  with working dimensions referenced in inches. Although these dimensions are illustrative of one embodiment, it should be appreciated that numerous variations to these dimensions and tolerances are realizable within the scope of the invention. Further embodiments, as described below also include working dimensions referenced in inches for illustrative purposes. These further embodiments are similarly not to be construed as limiting to possible variations in dimensions or tolerances. 
         [0026]    The seal resulting from insertion of the lid  30  into the cup  20  is formed by the compressive force between a portion of the annular wall  32  that makes contact with the inside of the cup  20 . The portion of the annular wall  32  that makes contact with the inside of the cup  20  may be at any point between the bottom base  36  and the top rim  34  provided the contact area forms a continuous path circumscribing the inside of the cup  20 , thereby forming a seal to prevent accidental spillage of a product in the container  10 . 
         [0027]    The height of the annular wall  32  is chosen to provide sufficient frictional force against the inside of the cup  20  after the lid  30  is inserted into the cup  20 . In one embodiment, the height of the annular wall  32  is constant. The frictional force occurs across the contact area of the annular wall  32  against the inside of the cup  20 . This frictional force prevents the lid  30  from becoming accidentally dislodged from the inside of the cup  20  thereby resulting in a loss of the compressive force between the annular wall  32  and the inside of the cup  20 , which further results in the loss of the seal  21 . The contact area has been found to be sufficient to prevent the lid from dislodging where a constant annular wall height of approximately one inch is used with a paper lid inserted into a paper cup. 
         [0028]      FIG. 3C  shows another embodiment of a lid  30 ′ distinguished from the lid  30  in  FIG. 3B  in that the annular wall  32  is not tapered and the concave lip  31  is made correspondingly wider so that the concave lip  31  can extend to and rest on the cup rim  22  ( FIG. 2 ). Not tapered, as used herein, means that the diameter of the top rim  34  is substantially equal to the diameter of the bottom base  36 . 
         [0029]      FIG. 4  shows a cross-sectional view of the cup  20  with lid  30  inserted to form a continuous seal  21  wherein the annular wall  32  of the lid  30  makes contact with the interior wall of the cup  20 .  FIG. 4  also shows the depth of insertion to be limited to the point where the concave lip  31  rests upon the cup rim  22 . The continuous seal  21  need not follow a straight line around the circumference of the interior wall of the cup  20 .  FIG. 4  shows one example of the contact area forming a seal  21  for illustrative purposes. The boundaries of the seal area will vary depending upon the planarity of the annular wall  32  and the planarity of the inside of the cup. The contact area may vary further depending upon the alignment of the lid  30  relative to the cup  20  upon insertion of the lid  30 . The line of the seal  21  is tolerant of misalignment between the inserted lid  30  and the cup  20  as well as perturbations on the interior wall of the cup  20  and the annular wall of the lid  30 . 
         [0030]      FIG. 5A  and  FIG. 5B  show another embodiment of a lid  50  distinguished from the lid  30  in  FIG. 3B  in that the lid  50  lacks the concave lip  31 . The lid  50  may be inserted further into the cup  20  as compared to lid  30  to the point where the annular wall  32  compresses against the inside of the cup  20  beyond what is necessary to sufficiently seal the contents of cup  20 .  FIG. 5C  shows another embodiment of a lid  50 ′ distinguished from the lid  50  in  FIG. 5B  in that the annular wall  32  is not tapered. 
         [0031]      FIG. 6  shows a cross-sectional view of the cup  20  with lid  50  inserted to form a continuous seal  21  wherein the annular wall  32  of the lid  50  makes contact with the interior wall of the cup  20 . The depth of insertion is not limited by a concave lip  31  ( FIG. 4 ). This embodiment simplifies the manufacture of the lid  50  by removing the manufacturing step of forming the concave lip  31 . The lid  50  is intentionally shown in an exaggerated manner to be misaligned to the cup  20  to illustrate a potential path of the seal  21  that is tolerant of such misalignment. 
         [0032]      FIG. 7A  and  FIG. 7B  show another embodiment of a lid  60  distinguished from the lid  30 ′ in  FIG. 3C  in that the surface  42  does not divide the annular wall  32  into a top wall section  38  and a bottom wall section  40 . In this embodiment, the surface  42  extends from the bottom base  36  of the annular wall  32 . The annular wall  32  has a similar thickness to the thickness of the surface  42 . 
         [0033]      FIG. 7C  shows another embodiment of a lid  60 ′ distinguished from the lid  60  in  FIG. 7B  in that the lid  60 ′ lacks the concave lip  31 . 
         [0034]    The embodiments of lids described in  FIG. 3A ,  FIG. 3B ,  FIG. 3C ,  FIG. 5A ,  FIG. 5B  and  FIG. 5C  may be readily manufactured using a conventional stamping process or by a forming and gluing process. The embodiments of lids described in  FIG. 7A ,  FIG. 7B  and  FIG. 7C  are preferably made with a stamping process. 
         [0035]    Although plastic lids may be manufactured with a stamping process, paper lids may be made with the following forming and gluing process. First, a flat stock of paper is stamped into flat trapezoidal sections. Second, the sections are rolled around a die form and two edges are glued together to create a tapered tube. Third, a lid bottom is stamped to form a circular shape with a straight lip orthogonal to the bottom. Then, the lid bottom is inserted into the lid and glued to the inner wall of the lid. 
         [0036]    While the invention has been shown and described with reference to specific preferred embodiments, it should be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the following claims.