Patent Publication Number: US-6991128-B1

Title: Splash inhibiting beverage container lid

Description:
FIELD OF THE INVENTION 
   The present invention relates to a lid for beverage cups, and more particularly to a lid that enables drinking from a cup without removal of the lid while minimizing accidental splashing or spillage of the liquid from the cup. 
   BACKGROUND OF THE INVENTION 
   It is well known to apply disposable lids to drinking cups for carry out sales of beverages, such as coffee. Such lids keep the liquid drink in the cup and prevent heat loss out to the surrounding environment. Many commonly used lids have a small drinking hole formed in the top surface so the user can drink from the cup without removing the lid. For example, U.S. Pat. No. 4,589,569 discloses a lid having a hole formed in its top wall, along with a recess formed in the top wall to accommodate the upper lip of the user. The hole is made relatively small to inhibit accidental splashing or spilling of the liquid through the drinking opening. 
   Conventional lids with drinking holes have to strike a balance between spillage and drinking flow. As the hole is made smaller, the amount of spillage prevented by the lid increases, but the amount of liquid flow through the hole as the user takes a drink decreases. Thus, by reducing the size of the hole, spillage is reduced at the expense of drinking flow. If the hole is too small, a comfortable amount of drinking flow cannot be achieved. If the hole is made larger to achieve better drinking flow, more liquid can accidentally spill or splash out through the enlarged hole. Prior art lid designs typically include longer side walls so that the upper wall of the lid is well above the top rim of the cup. However, liquid still spills out through the drinking hole. 
   There are three basic types of liquid spillage from lidded cups: vertical, horizontal and swirling. Vertical spillage can be caused by the cup being vertically slammed too hard on a rigid surface. The liquid in the cup experiences negative gravity acceleration and shoots vertically up to the lid. Any liquid aligned with the drinking hole shoots out of the cup through the hole. Horizontal spillage occurs when the cup is horizontally displaced. The horizontal motion causes a wave of liquid to ride up the side of the cup, along the upper wall of the lid, and out the drinking hole. Swirling spillage occurs when arcing translational movement of the cup causes a wave of fluid to ride up the side of the cup and along the circumference of the cup and lid. When the wave reaches the drinking hole, liquid splashes out from the cup through the hole. 
   Because of the trade off between spillage prevention and drinking flow, prior art lid designs simply cannot provide adequate spillage prevention, while still providing adequate drinking flow when the user tips the cup for a drink. Raising the top wall of the lid well above the rim of the cup does little to abate the vertical, horizontal and swirling waves of liquid that are responsible for most accidental spillage. There is a need for a lid design that improves spillage protection without comprising the desired drinking flow rate through the lid. 
   SUMMARY OF THE INVENTION 
   The present invention solves the aforementioned problems by providing a drinking cup lid that inhibits inadvertent spillage from the cup while still providing good drinking flow when the cup is tilted for a drink. 
   The lid of the present invention, for covering a drinking cup containing a liquid, includes a top wall having a generally circular periphery, an annular sidewall downwardly depending from the top wall periphery, a drinking opening formed adjacent to the periphery, and a regulator valve formed under the drinking opening. The regulator valve includes a first sidewall structure downwardly depending from the lid adjacent the drinking opening and terminating in a first bottom wall, and a first aperture formed in the first sidewall structure or the first bottom wall, wherein the first aperture includes at least one of a generally taper shaped portion and an irregularly shaped edge. 
   In another aspect of the present invention, the lid includes a top wall having a generally circular periphery, an annular sidewall downwardly depending from the top wall periphery, a drinking opening formed adjacent to the periphery, and a wave-breaker recess formed in the top wall having a sidewall that extends downwardly. The wave-breaker recess sidewall includes a first portion facing toward the drinking opening and a second portion facing away from the drinking opening. The first portion slopes away from the top wall at an angle that is generally between 15 degrees and 45 degrees relative to a line perpendicular to the top wall. 
   In yet another aspect of the present, the lid includes a top wall having a generally circular periphery, an annular sidewall downwardly depending from the top wall periphery, a drinking opening formed adjacent to the periphery, and a regulator valve formed under the drinking opening. The regulator valve includes a sidewall structure downwardly depending from the lid adjacent the drinking opening, and a plurality of apertures formed in the sidewall structure and positioned thereon in an opposing manner. 
   In still yet another aspect of the present, the lid includes a top wall having a generally circular periphery, an annular sidewall downwardly depending from the top wall periphery, a drinking opening formed in the top wall adjacent to the periphery, a regulator valve formed under the drinking opening, and a wave-breaker recess. The regulator valve includes a first sidewall structure downwardly depending from the top wall adjacent the drinking opening and terminating in a first bottom wall, and a first aperture formed in the first bottom wall. A wave-breaker recess formed in the top wall having a sidewall that extends downwardly. The wave-breaker recess sidewall includes a first portion that faces but is separated from the annular sidewall to form a channel therebetween with the regulator valve disposed in the channel, and a second portion facing away from the channel. 
   In still yet one more aspect of the present, the lid includes a top wall having a generally circular periphery, an annular sidewall downwardly depending from the top wall periphery, a plurality of clustered together drinking openings formed in the top wall, and a wave-breaker recess formed in the top wall having a sidewall that extends downwardly. The wave-breaker recess sidewall includes a first portion facing toward the drinking openings and a second portion facing away from the drinking opening. 
   Other objects and features of the present invention will become apparent by a review of the specification, claims and appended figures. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a top view of the beverage container lid of the present invention. 
       FIG. 2  is a side view of the beverage container lid of the present invention mounted on the rim of a beverage container. 
       FIG. 3A  is a side cross-sectional view of the beverage container lid of the present invention, taken along the lines  3 A— 3 A of  FIG. 1 . 
       FIG. 3B  is a side cross-sectional view of the beverage container lid of the present invention, taken along the lines  3 B— 3 B of  FIG. 1 . 
       FIG. 4  is a cross-sectional view of the regulator valve of the present invention. 
       FIGS. 5A–5I  are cross-sectional views of alternate embodiments of the regulator valve of the present invention. 
       FIG. 5J  is a side view of an alternate embodiment of the regulator valve of the present invention. 
       FIG. 6A  is a cross-section view showing the formation of the regulator valve at the periphery of the beverage container lid of the present invention. 
       FIG. 6B  is a cross-section view showing the formation of the regulator valve in the annular sidewall of the beverage container lid of the present invention. 
       FIG. 7A  is a cross-sectional view of the regulator valve of the present invention, illustrating the aperture tapered portions formed by a mechanical punch. 
       FIG. 7B  is a top view of the regulator valve of the present invention, illustrating the aperture tapered portions and the irregularly shaped edges thereof formed by a mechanical punch. 
       FIG. 8A  is a side cross-sectional view of the beverage container lid of the present invention, taken along the lines  8 A— 8 A of  FIG. 8B , showing the raised top wall portion and the sloping sidewall portion of the wave-breaker recess. 
       FIG. 8B  is a top view of the beverage container lid of the present invention showing the raised top wall portion and the sloping sidewall portion of the wave-breaker recess. 
       FIG. 9A  is a top view of the beverage container lid of  FIG. 1 , but with a plurality of drinking holes and no regulator valve. 
       FIG. 9B  is a top view of the beverage container lid of  FIG. 8B , but with a plurality of drinking holes and no regulator valve. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The present invention is a disposable beverage container lid  1  as shown in  FIGS. 1 and 2 . The lid  1  mounts to the rim of a beverage container (i.e. a beverage cup) and allows the user to drink from the cup without removing the lid while greatly minimizing accidental spillage of the liquid from the cup. 
   The beverage container lid  1  of the present invention includes a top wall  10  with a generally circular periphery  12 , and an annular sidewall  14  depending from the periphery  12 . The sidewall  14  includes an annular recess  16  formed therein for receiving the upper rim  18  of a cup  20 . While the lid  1  of the present invention can be used with any shape and style cup, it is particularly suitable when used with disposable carry-out style paper or Styrofoam cups having a generally circular upper rim  18 . Annular recess  16  has a shape and size to engage with the cup rim  18  in a liquid tight manner to secure the lid  1  to the cup  20 . For example, for cups with a rounded bead formed on the upper cup rim  18 , the annular recess  16  has a rounded cross-section to tightly receive the rounded bead. 
   A regulator valve  22  is formed under the top wall  10  adjacent the periphery  12 , as best shown in  FIGS. 1 ,  3 A, and  4 . The regulator valve  22  is disposed directly under a drinking (first) opening  24  formed in the top wall  10 , and includes a first sidewall  26  depending from the top wall adjacent to the drinking opening  24  and terminating in a first bottom wall  28 . A second opening  30  is formed in the first bottom wall  28 , with a second sidewall  32  depending from the first bottom wall  28  adjacent to the second opening  30  and terminating in a second bottom wall  34 . First and second apertures  36 / 38  are formed in the first bottom wall  28  (preferably one on either side of second opening  30 ). A third aperture  40  is formed in the second bottom wall  34 . The user drinks from the cup by placing his/her lips over the drinking opening  24 , and tilting the cup until liquid in the cup flows through the apertures  36 / 38 / 40  and out drinking opening  24 . 
   A wave-breaker recess  42  is formed in the top wall  10  as best shown in  FIGS. 1 ,  3 A and  3 B, and includes a shaped sidewall  44  extending downwardly and terminating in a wave-breaker bottom wall  46 . The shaped sidewall  44  includes an arcuate shaped first portion  48  and a non-linear second portion  50 . First portion  48  faces but is separated from (and is concentric with) a portion of annular sidewall  14 , forming a channel  52  therebetween. The regulator valve  22  is disposed in channel  52 . The non-linear second portion  50  faces away from regulator valve  22  and preferably has a concave shape. In the preferred embodiment, the wave-breaker bottom wall  46  extends further below the top wall  10  than does regulator valve  22 . 
   Periphery inhibitor recesses  54  are formed in the top wall  10 , adjacent to the periphery  12 , with sidewalls  56  extending down and terminating in bottom walls  58 , as best shown in  FIGS. 1 and 3B . Preferably, there are two periphery inhibitor recesses  54  that protrude down and into channel  52 , one on either side of the regulator valve  22 . A very small vent hole  60  is preferably formed in top wall  10  away from regulator valve  22 , to prevent a vacuum from forming in the cup as the user drinks. 
   The above described beverage container lid  1  provides a desired drinking flow through the regulator valve  22  when the beverage cup  20  is tilted by the user for drinking, but minimizes spillage out of the cup  20  when waves are created inside the cup by vertical, horizontal or swirling motions. The regulator valve  22 , the wave-breaker recess  42  and the periphery inhibitor recesses  54  help minimize spillage in the following manner. The regulator valve  22  provides a plurality of smaller apertures  36 / 38 / 40  through which the liquid flows for drinking that are all disposed below the top wall  10  of the lid  1 , instead of just a single larger aperture formed in the lid top wall. Preferably, all of the apertures  36 / 38 / 40  are each smaller than drinking opening  24 . Together, the smaller apertures  36 / 38 / 40  provide good drinking flow when the cup is tilted, yet individually provide smaller targets for the liquid to splash through. Further, a wave of liquid incident on regulator valve  22  is typically aligned with as few as one of the small apertures  36 / 38 / 40 , thus reducing the amount of liquid from the wave that can escape through the lid. In fact, a wave riding up the cup wall and reaching the periphery  12  adjacent the valve  22  may not be directly aligned with any of the apertures. Moreover, should liquid splash through one or more of the apertures  36 / 38 / 40 , the liquid would still have to find its way up and out of the drinking opening  24  (i.e. the first and second sidewalls  26 / 32  would further dampen splashed liquid). Liquid that does not reach the drinking opening  24  would drain back into the cup via the apertures  36 / 38 / 40 . 
   Wave-breaker recess  42  reduces splashing by defining the narrow channel  52  in which the regulator valve  22  is disposed. Waves of liquid headed toward the regulator valve  22  will be significantly dampened or blocked by the first portion  48  of the wave-breaker recess sidewall  44  before reaching the regulator valve  22 , which is protected inside the channel  52 . Moreover, the non-linear (concave) shaped second portion  50  of wave-breaker recess  42  acts as a reflector wall for reflecting waves of liquid traveling along the top wall  10 . The non-linear (concave) shape helps dissipate the wave&#39;s energy and prevents it from reaching the regulator valve  22 . 
   Periphery inhibitor recesses  54  block waves of liquid trying to travel along the periphery of lid  1  (e.g. down channel  52 ). With one periphery inhibitor disposed on each side of the regulator valve  22 , any such liquid waves would be blocked or dissipated before reaching the regulator valve  22 . Periphery inhibitor recesses  54  can be formed anywhere along the periphery  12  of lid  1 . For spillage prevention, periphery inhibitor recesses  54  should ideally be disposed as close as possible to the regulator valve  22  along periphery  12 . However, some spacing should be provided therebetween so that the user can seal their lips around regulator valve  22  without interference from recesses  54 , and so that any spilled liquid does not accumulate on the bottom wall  58 . 
   The regulator valve  22 , the wave-breaker recess  42  and the periphery inhibitors  54  work together to break up waves of liquid and minimize spillage caused by vertical, horizontal and swirling motions of the cup. It should be noted, however, that any of these three elements alone would help prevent accidental spillage. 
   The lid  1  of the present invention is preferably made of plastic, using a thermal forming process, having a thickness of approximately 0.015 inch. In order to retrieve the formed lid from the thermal forming mold, all sidewall surfaces (e.g. sidewalls  14 ,  26 ,  32 ,  44  and  56 ) preferably have a 5– 15  degree angle of inclination (relative to vertical). A lid  1  according to the present invention has been constructed with annular sidewall  14  having a vertical height of 0.718 inches, where the regulator valve  22 , the wave-breaker recess  42 , and the periphery inhibitor recesses  54  extend down below top wall  10  by 0.25 inches, 0.656 inches, and 0.25 inches, respectively. The apertures  36 / 38 / 40  each have a diameter of 0.09 inches, and wave-breaker sidewall second portion  50  has a radius of curvature of 1.75 inches. 
   The apertures  36 / 38 / 40  are preferably formed in the first and second bottom walls  28 / 34  for ease of manufacture and because most of the wave action in beverage cups causing accidental spillage can be mainly from horizontal and swirling motions. However, apertures  36 / 38 / 40  can alternately be formed in first and second sidewalls  26 / 32  as shown in  FIG. 5A , or both as illustrated in  FIG. 5B . The second sidewall  32  and bottom wall  34  can be omitted, with the apertures formed in the first sidewall  26  and/or in the first bottom wall  28 , as shown in  FIGS. 5C ,  5 D and  5 E. The first bottom wall  28  could also be omitted, with the apertures formed in the first sidewall  26  that is angled or rounded, as shown in  FIGS. 5F and 5G . The number of apertures on each of the first and second sidewalls  26 / 32  and/or first and second bottom walls  28 / 34  can be varied, as shown in  FIGS. 5H and 5I . Finally, the apertures formed in the sidewalls can face toward the wave-breaker recess  42  and/or the adjacent portion of annular sidewall  14 , as opposed to facing along the channel  52 , as illustrated in  FIG. 5J . Where the apertures are formed in the sidewalls, it is preferably to form pairs of the apertures opposing one another so that any wave incident upon one aperture would not be incident upon another aperture formed on the opposing side of the sidewall. The number and locations of the apertures can vary depending upon the amount of splash protection that is desired and the ease of manufacturing, so long as a plurality of such apertures are formed in regulator valve  22  below the level of the drinking opening formed in the top wall  10 . 
   FIGS.  4  and  5 A– 5 J include cross-sectional views illustrating two opposing faces of sidewall  26  or sidewall  32 . It should be understood that each sidewall  26  or  32  of the present invention is a three dimensional structure that encircles opening  24  or opening  30  and extends down in most cases to a bottom wall  28  or  34 . Each sidewall structure  26  or  32  can be rounded or include opposing flat panel portions, and need not have the exact dimensions of the opening from which it extends. Further, while the regulator valve  22  is shown as being formed in top wall  10 , valve  22  can alternately be formed at the periphery  12  as shown in  FIG. 6A , or in the annular sidewall  14  as shown in  FIG. 6B . 
   The apertures  36 / 38 / 40  are shown as substantially round, clean-cut holes formed in the lid material, which are aesthetically pleasing to the user. In practice, however, these apertures can be any shape, including squares, diamonds, oblong slits, etc., all of which allow fluid to flow therethrough. 
   It has been discovered that forming irregularly shaped, ragged apertures improves the performance of the regulator valve  22 .  FIGS. 7A and 7B  illustrate such apertures, where a mechanical punch is used to form apertures  36 / 38 / 40 . After bottom walls  28 / 34  have been formed, a mechanical punch is pressed through these walls to form apertures  36 / 38 / 40 . The stretching and ripping action of the mechanical punch has two effects: it forms a generally taper shaped portion  62  of each aperture, and it forms an irregularly shaped edge  64  at the termination of the taper shaped portion  62 . Both the tapered portion  62  and its irregular shaped edge  64  serve to further dampen fluid wave motion under the lid, but effectively still allow fluid to enter each aperture, for example, when a suction or vacuum is applied to the drinking opening  24 . It is possible to manipulate the mechanical punch process to form tapered portion  62  that terminates in a relatively clean-cut, regularly shaped edge, or to form an irregularly shaped edge  64  on apertures  36 / 38 / 40  without forming the tapered portion  62 , with each providing a useful fluid dampening effect. However, it is believed that the combination of the generally taper shaped portion  62  and irregularly shaped edge  64  provides even better fluid dampening results. The tapered portion  62  and/or irregular edge  64  can be formed in any or all of the apertures  36 / 38 / 40  shown in any of the figures. 
     FIGS. 8A and 8B  illustrate another feature of the present invention, where a portion  10   a  of top wall  10  containing regulator valve  22  is raised higher and made narrower than the remaining portion of top wall  10 . Additionally, a portion  44   a  of shaped sidewall  44  that extends from top wall portion  10   a  down to wave-breaker recess bottom wall  46  is sloped at a greater angle θ relative to vertical (i.e. relative to a line L perpendicular to top wall portion) compared to the nominal mold angle inclination of 5–15 degrees. Preferably the sloping angle θ is approximately 30°, but can be any angle greater than 15° and less than approximately 45°. The raised wall portion  10   a  and sloping sidewall portion  44   a  provide a superior contour for the user&#39;s lips, while still allowing the wave-breaker recess  42  to block waves of liquid from reaching regulator valve  22  and providing space for the user&#39;s nose. User&#39;s typically drink from covered coffee or similar cups by creating a suction over the mouth piece while tipping the cup, as opposed to pouring the fluid into the mouth. A superior lid contour is provided for the user&#39;s mouth by the raised and narrowed top wall portion  10   a , the sloping sidewall portion  44   a  and the annular sidewall  14 , allowing the user to comfortably form a seal around drinking opening  24  and better control the draw of liquid through the regulator valve  22  at a desired rate. 
   While regulator valve  22  of the present invention has been shown to reduce the amount of accidental spillage by as much as an order of magnitude,  FIGS. 9A and 9B  illustrate the cup lids of  FIGS. 1 and 8B  respectively, where the single drinking opening  24  and regulator valve  22  formed underneath are replaced by a plurality of drinking openings  66  with no regulator valves underneath. By replacing a single drinking opening  24  with two or more smaller drinking openings  66 , accidental spillage is reduced compared to the widely known single drinking opening cup lids (because the smaller multiple openings provide smaller targets for moving liquid inside the cup). The reduction of accidental spillage using multiple drinking openings  66  is enhanced when combined with one or more of the following: the wavebreaker recess  42 , the sloped sidewall portion  44   a , the higher and narrower top wall portion  10   a , the taper shaped portion  62  (formed under drinking openings  66 ), the irregularly shaped edge  64  (of drinking openings  66 ), and/or the inhibitor recesses  54 . The greater the number of drinking openings  66 , the smaller in size they can be and still collectively provide the desired drinking flow. To be effective, the drinking openings  66  need to be clustered together (as used herein, clustered together means that the drinking openings are sufficiently close together such that users can form a seal with their lips around all of the drinking openings). 
   It is to be understood that the present invention is not limited to the embodiments described above and illustrated herein, but encompasses any and all variations falling within the scope of the appended claims. For example, the regulator valve  22 , the wave-breaker recess  42  and/or the inhibitor recesses  54  can extend down below the rim of the cup. Also, shaped sidewall second portion  50  of wave-breaker recess  42  can have any non-linear shape (e.g. convex shape instead of concave shape disclosed above) that helps dissipate the energy of waves incident thereon. While the present invention is ideal for disposable lids made of thin plastic, it is certainly applicable to re-usable lids as well. Lastly, with the generally taper shaped portions  62 , irregularly shaped edge  64 , wavebreaker recess  42  and/or the inhibitor recesses  54 , the regulator valve  22  can include just a single aperture and still provide sufficient spill prevention.