Abstract:
A splash-proof lid assembly is a substantially planar unit which is made up of a disc and a bottom section that is rotatably connected to the disc. By rotating the bottom section to the underside of the disc, a tube is formed which allows for drinking from a cup once the lid is placed on the cup.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 09/545,159 filed Apr. 7, 2000, now U.S. Pat. No. 6,296,141 issued Oct. 2, 2001, which was in turn, a continuation-in-part of patent application Ser. No. 09/095,419 filed Jun. 8, 1998, now abandoned. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a removable lid for a cup and, more particularly, to a lid assembly which is used to form the lid. The lid of the present invention avoids inadvertent splashing which occurs due to unintentional movement of the cup. 
     2. Art Related to the Invention 
     Splash-proof lids for drinking cups are known. Typically, they comprise a round, removable cover which fits tightly over the top opening of a cup to prevent unwanted spillage of the contents of the cup while allowing the user to drink the contents of the cup even though the lid remains on the cup. To allow the user to drink the contents of the cup while the lid remains on the cup, both a drinking hole and an air hole are provided in the lid. Both holes are configured to prevent unwanted loss or spillage of the contents of the cup which occurs when the cup is unintentionally moved. Typically, such lids are used on disposable cups which the user takes on a train, a plane, in a boat, or in a car. 
     The drinking hole is usually positioned at the edge of the lid next to the side wall of the cup, while the air hole is positioned either centrally in the lid or along the edge of the lid next to the side wall of the cup, opposite the drinking hole. 
     One example of such a lid is taught in U.S. Pat. No. 4,322,014. In the &#39;014 patent, a splash-proof lid has both a drinking hole and an air hole wherein both holes have a baffle arrangement to prevent the liquid contents of the cup from exiting the cup. The baffle arrangement is such that the axis of the baffle, taken along the fluid flow lines, forms a straight line and does not follow the contour or radius of the exterior of the lid. The baffle arrangement in the &#39;014 patent is rather complicated. 
     In order to make the lid of the &#39;014 patent, two separate pieces are either molded separately and then subsequently glued, or the lid is molded as one unitary piece. Molding is obviously difficult and assembling the two pieces is time-consuming. 
     Another example of a splash-proof lid is taught in U.S. Pat. No. 4,394,928. Here a special cup having a ledge functions with the lid to form a curved channel through which liquid flows to the drinking hole. This has the advantage of a one step molding process, but requires a special cup to allow the lid to function. 
     There is a need for a simplified design for a splash-proof lid which can function with a conventional disposable cup. 
     SUMMARY OF THE INVENTION 
     A simplified lid assembly for making a splash-proof lid for a cup has now been discovered. The lid is intended to be disposable and for use with disposable drinking cups such as the type used for coffee, tea, etc. The lid has an air hole, a drinking hole and is designed to avoid spillage of the contents of the cup through the drinking hole and the air hole. 
     It has been discovered that the jiggling or unintended movement of the cup causes a wave to form on the surface of the liquid and to travel back and forth across the surface of the liquid crashing against the side walls of the cup. When the wave hits the side walls of the cup, it splashes out of the drinking hole or the air hole when the air hole is positioned next to the side wall of the cup. Thus, it is the movement of the waves on the surface of the liquid in the cup and its crashing against the side wall that causes the splashing and the spillage of the liquid. 
     It has also been found that when the air hole is made small and positioned in the center of the lid that splashing or spillage due to the wave through the air hole does not occur. Furthermore, it has been found that when the air hole is made rather small compared to the drinking hole, that the air hole will still function to allow liquids to flow out of the drinking hole and air in through the air hole. Thus, in the present invention, the air hole is positioned in the center of the lid and made relatively small compared to the drinking hole. 
     To avoid spillage out of the drinking hole, an arched tube is employed in fluid communication with the drinking hole. The arched tube of the present invention blocks the wave from crashing directly into the drinking hole and redirects the liquid back into the cup to prevent spillage of the contents of the cup through the drinking hole. 
     The arched tube extends above and below the planar surface of the lid so as to form a chamber. The drinking hole is positioned in the top of the tube and the top of the tube rises above the planar surface of the lid. The bottom of the tube extends below the planar surface of the lid and contains inlets through which the contents of the cup travel to reach the drinking hole. The arched tube follows the curvature of the lid, is centered on the drinking hole, and is in fluid communication with the drinking hole. The arched tube is formed along the edge of the lid and has a plurality of inlets to allow the liquid contents of the cup to travel into the tube. The inlets can be in the bottom of the tube, in the end walls of the tube, or both. The drinking hole is positioned in the top of the tube to allow the liquid contents to flow from the cup through the tube and into the user&#39;s mouth. The radius of the tube is less than the radius of the lid and the radius of the tube is concentric with the radius of the lid. The lid itself has an engaging periphery to allow it to engage with the rim of a cup and become removably affixed to the rim of the cup. In this way, the lid of the present invention fits a conventional disposable cup and no special cup must be employed with the lid of the present invention. 
     It has been discovered that the lid of the present invention can be easily made in a one step molding process from a unique lid assembly which is disclosed herein. The lid assembly is made up of two pieces, one piece being the disc that makes up the majority of the lid while the other piece is a bottom section which forms the bottom portion of the arched tube and a portion of the engaging periphery. The disc and the bottom section are rotatably connected to one another along their peripheries such that the lid is assembled by rotating the disc and the bottom section together. In the molding operation, the disc and the bottom section form one, essentially planar, element. 
     Broadly, the splash-proof lid for a drinking cup in accordance with the present invention comprises: 
     a circular disc having a snap fitting periphery for engagement with a cup rim; 
     an air hole in said disc which is positioned in the center of said disc; 
     an arched tube adjacent said snap fitting periphery, said tube having a radius that is concentric with the radius of said disc and less than the radius of said disc, said tube having a top portion which is above the top surface of said disc and a bottom portion which is below the bottom surface of said disc; 
     a drinking hole in a top wall of said tube, said tube centered on said drinking hole, said air hole being smaller than said drinking hole; and 
     at least two inlets in said tube positioned in said bottom portion of said tube, such that said inlets are in fluid communication with said drinking hole to allow a user to drink through the lid when the lid is placed on top of a drinking cup. 
     Broadly, the splash-proof lid assembly for making a lid for a drinking cup in accordance with the present invention comprises: 
     a circular disc having a periphery; 
     a first snap fitting periphery portion extending around a first portion of said periphery, said first snap fitting periphery portion absent from a second portion of said periphery; 
     a tube top portion with a drinking hole therein, said tube top portion positioned adjacent to said periphery at said second portion of said periphery, said tube top portion rising above the top surface of said disc; 
     an air hole positioned in the center of said disc; 
     a bottom section having an arcuate side, said bottom section having a second snap fitting periphery portion adjacent said arcuate side, and a tube bottom portion having at least two inlets therein, said tube bottom portion adjacent said second snap fitting periphery portion, 
     said bottom section rotatably attached to said disc along said periphery of said disc such that when said bottom section is rotated under said disc, said second snap fitting periphery portion is positioned in said second portion of said periphery, said tube bottom portion aligns with said tube top portion to form an archede tube in said lid, said inlets are in fluid communication with said drinking hole, and said first snap fitting periphery portion and said second snap fitting periphery portion for a complete snap fitting periphery of said lid. 
     Preferably, the inlets are in the bottom wall of the tube, however, the inlets can also be in the end wall of the tube, provided they are in the end wall of the bottom portion of the tube, i.e. below the bottom surface of the disc. 
     Preferably, the arched tube forms an angle of about 30 to about 60° with respect to its radius. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other aspects of the present invention may be more fully understood by reference to one or more of the following drawings wherein: 
     FIG. 1 is a perspective top view of the assembled lid of the present invention; 
     FIG. 2 is a perspective bottom view of the assembled lid of the present invention; 
     FIG. 3 is a top view of the lid assembly of the present invention; and 
     FIGS. 4A-4C are cross-sections of the lid assembly of the present invention along the lines  4 A- 4 A of FIG.  3  and illustrate the assembly process in accordance with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 illustrates a top perspective view of the assembled lid  8 . Lid  8  comprises disc  10  having raised center section  11  on top thereof, snap fitting periphery  12  along the sides thereof, air hole  16  extending therethrough, and arched tube  18  with top portion  19  and having drinking hole  14  extending therethrough. Top portion  19  rises above the surface of disc  10 . 
     FIG. 2 is a perspective view of the bottom of lid  8 . As shown in FIG. 2, bottom portion  20  of tube  18  is sunken below the bottom surface of disc  10 . Bottom portion  20  has two inlet openings  21  and  22 . Tube  18  is in fluid communication with drinking hole  14  such that when a user drinks from a cup, the liquid contents of the cup flow through inlet openings  21 ,  22  into tube  18 , through tube  18  to drinking hole  14  and into the user&#39;s mouth. 
     Bottom section  30  is used to form tube  18  and a portion of snap fitting periphery  12 . Bottom section  30  comprises arcuate side  32  with snap fitting periphery portion  34 . Disc  10  has snap fitting periphery  36 . Snap fitting periphery portion  36  along with snap fitting periphery portion  34  makes up snap fitting periphery  12 . 
     Lid  8  is securely held on a cup due to the engagement between snap fitting periphery portions  34 ,  36  and the rim of the cup. This engagement between snap fitting periphery portions  34  and  36  occur when the lid  8  is pressed down onto the rim of the cup. Such snap fitting periphery portions  34 ,  36  are conventional and well-known to those of skill in the art. The snap fitting periphery portions  34 ,  36  house the lip of the cup when the two are joined. 
     As shown in FIG. 3, which is a top view of lid  8  unassembled into its two pieces, bottom section  30  and disc  10 , bottom section  30  and disc  10  are connected along their respective peripheries at joint  38 . Bottom section  30  has arched side  32  with snap fitting periphery portion  34 . Bottom section  30  has bottom portion  20  which forms the bottom and a part of the lower side walls of tube  18 . Inlet openings  21 ,  22  are shown in the bottom wall of portion  20 . 
     FIG. 4A illustrates a cross-section of unassembled lid  8  of the present invention. As shown therein, bottom section  30  is connected to disc  10  by joint  38 . Joint  38  is a conventional weak spot which allows for the rotation of bottom section  30  under disc  10  as shown in FIGS. 4B and 4C. 
     Bottom portion  20  has bottom wall  40  and lower side walls  42  and  44 . Top portion  19  has top wall  46  and upper side walls  48  and  50 . When bottom section  30  is rotated around joint  38 , bottom wall  40 , top wall  46 , lower side walls  42 ,  44  and upper side walls  48 ,  50  form tube  18 . 
     It is preferred that bottom section  30  is securely fixed to disc  10  by means of a latch mechanism which is illustrated as projection  52  and channel  54 . It will be understood, however, that such a latching mechanism is not necessary because, when bottom section  30  is rotated about joint  38  so as to join bottom section  30  to the underside of disc  10 , the force between the rim of the cup and snap fitting periphery portion  32  is enough to maintain the engagement between disc  10  and bottom section  30 . It will be appreciated that the rim of the cup forces snap fitting periphery portion  32  up to and against disc  10  as shown in FIG.  4 C. Rim  56  of cup  58  is illustrated in FIG.  4 C. 
     It should be appreciated that although only two inlets  21  and  22  are illustrated, additional inlets in tube  18  may be employed. Specifically, there can be inlets in lower end walls  60  and  62  of tube  18 . Lower end walls  60  and  62  are illustrated in FIG.  2 . 
     It will also be appreciated that although FIG. 3 illustrates that bottom section  30  is positioned directly opposite drinking hole  14 , joint  38  can be at another location along the periphery of disc  10 , provided that when section  30  is rotated about joint  38 , bottom portion  20  aligns with top portion  19  to form tube  18 . 
     It will also be noted in FIGS. 4A-4C that disc  10  has no snap fitting periphery in the area in which snap fitting periphery portion  34  resides. Thus, disc  10  has no snap fitting periphery along a portion of its periphery, that portion being the portion which is filled by snap fitting periphery portion  34  upon rotation of bottom section  30  against disc  10 . 
     Obviously, the dimensions of the lid assembly are adjusted accordingly depending on the size of the cup. Typically, disposable cups are made in three sizes, small, medium and large. The lid of the present invention will have its dimensions adjusted accordingly for each one of the cup dimensions. 
     The lid assembly of the present invention is made in any conventional plastic molding process wherein the lid assembly is molded in a one-step molding operation in a conventional manner using conventional equipment. 
     It will be appreciated by those of skill in the art that lid  8  in the unassembled form, i.e. lid assembly as shown in FIGS. 3 and 4A, easily nest with one another. This is important for the purposes of shipping the lids to different users. As will be appreciated, the unassembled lid  8  takes up less volume than the assembled lid  8  as shown in FIGS. 1,  2  and  4 C. 
     It will be appreciated that it is preferred that disc  10  employ a moat as shown in FIG. 1 so as to catch any liquid that may escape from drinking hole  14 . This moat is not essential and need not be present in the invention as shown in FIGS. 4A-4C. 
     It will also be appreciated that the cross-sectional dimensions of tube  18  may be rounded as shown in FIGS. 1 and 2, or may be rectangular in shape as shown in FIGS. 4A-4C. 
     It will be understood that the claims are intended to cover all changes and modifications of the preferred embodiments of the invention herein chosen for the purpose of illustration which do not constitute a departure from the spirit and scope of the invention.