Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 09/957,327 filed Sep. 20, 2001, now U.S. Pat. No. 6,533,139 issued Mar. 18, 2003, which in turn 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 is especially suited for disposable coffee cups and drinking cups. The lid assembly of the present invention avoids inadvertent splashing which occurs due to 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 of the problems in the prior art is that various lid assemblies tend not to be completely splash-proof. There is a need to invent a cup which is simple in design but yet splash-proof. Furthermore, there is a need to provide a simple design which can be employed with disposable cups. 
     SUMMARY OF THE INVENTION 
     A simple 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 which is centrally located in the lid and a drinking hole which is located along the periphery of the lid. The lid is especially 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 wave on the surface of the liquid in the cup and its crashing against the side walls of the cup 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 spillage or splashing due to the wave through the air hole does not occur. Furthermore, it has been found that if 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. In other words, the drinking hole is much larger than the air hole. 
     To avoid spillage out of the drinking hole, a large expansion chamber is employed which is in fluid communication with the drinking hole and in fluid communication with the interior of the cup. The chamber has one or more inlets which are positioned in the bottom wall and/or the side wall of the chamber. The drinking hole is positioned in the top wall of the chamber. The drinking hole and the inlets of the chamber are not in vertical alignment with each other. Thus, when any portion of the wave comes through the inlets into the chamber, it does not go through the drinking hole, but rather, is redirected back into the cup or contained in the chamber. This prevents spillage of the contents of the cup through the drinking hole. 
     The chamber has a bottom portion which extends below the lid and down into the area which is formed by the cup. The top portion of the chamber can be either coplanar with the top surface of the lid or extend above the top surface of the lid. 
     Preferably, the chamber has an arched or crescent shape, when viewed from above. The arched chamber preferably extends both above and below the planar surface of the lid. The drinking hole is positioned in the top wall of the chamber. The bottom chamber portion extends below the planar surface of the lid and preferably contains one or more inlets through which the contents of the cup travel to reach the drinking hole. The arched chamber follows the curvature of the lid, is centered on the drinking hole, and is in fluid communication with the drinking hole. The arched chamber is formed along the edge of the lid and has one or more inlets to allow the liquid contents of the cup to travel into the chamber. The inlets can be in the bottom wall of the chamber, in the end walls of the chamber, or the side walls of the chamber. The drinking hole is positioned in the top wall of the chamber to allow the liquid contents to flow from the cup through the chamber and into the user&#39;s mouth. The center line of the chamber (assuming the chamber is essentially cylindrical in cross section) follows a radial line from the center of the lid that is less than the radius of the lid and is concentric with the radius of the lid. The lid itself has an engaging periphery to allow it to engage the rim of the 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 is preferred that the lid of the present invention be molded into a one-step molding process. For example, the lid assembly is suitably made by thermoforming. In this process, the lid is made up of two pieces, one piece which is a disc that makes up the majority of the lid and can generally be referred to as the top of the lid while the other piece is a bottom section which forms the bottom portion of the chamber. The bottom section of the lid can be rotatably connected to the disc or, alternatively, can be separate from the disc. 
     Broadly, the splash-proof lid assembly for making a 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 positioned in said disc at the center of said disc; 
     a drinking hole positioned in said disc adjacent said snap fitting periphery of said disc, said drinking hole being larger than said air hole; 
     a first engagement means positioned on said disc at the underside of said disc between said snap fitting periphery and said air hole; 
     a bottom lid section having an arcuate side which mates with a portion of said snap fitting periphery of said disc, and a second engagement means for engaging with said first engagement means when said arcuate side mates with said snap fitting periphery; and 
     a chamber formed between said disc and said bottom lid section when said bottom lid section is placed against the underside of said disc and said first engagement means engages said second engagement means and said arcuate side mates with said portion of said snap fitting periphery, said chamber having a bottom chamber portion which is formed by said bottom lid section and extends below said disc, said chamber being centered on said drinking hole, said disc forming a top chamber portion, said chamber having one or more inlets formed in the bottom chamber portion and said inlet not being in vertical alignment with said drinking hole. 
     Preferably, said bottom lid section is rotatably attached to said disc along said snap fitting periphery of said disc and said arcuate side of said bottom lid section. Said bottom lid section can also be separate from said disc until said bottom section is mated with said disc. 
     Preferably, the top chamber portion, which is formed in said disc, extends upwardly from the planar surface of said disc, and is centered on said bottom chamber portion, said drinking hole being centered in said top chamber portion. 
     The inlets in the bottom chamber portion are preferably in the side walls, the end walls, or the bottom of said bottom chamber portion. 
     In one embodiment, the top portion of said chamber is flat and coplanar with said disc. 
     More preferably, the chamber has an arcuate shape which is concentric with the snap fitting periphery of said disc. 
     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 enter of said disc; 
     an arched chamber adjacent said snap fitting periphery, said chamber having a center line which follows a radial line that is concentric with the radius of said disc and less than the radius of said disc, said chamber having a top portion which extends above the top surface of said disc and a bottom portion which extends below the bottom surface of said disc; 
     a drinking hole in a top wall of said chamber, said chamber centered on said drinking hole, said air hole being smaller than said drinking hole; and 
     one or more inlets in said chamber positioned in said bottom portion of said chamber, such that said inlet is 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 can be defined as comprising: 
     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 chamber top portion with a drinking hole therein, said chamber top portion positioned adjacent to said periphery at said second portion of said periphery, said chamber 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 chamber bottom portion having one or more inlets therein, said chamber 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 chamber bottom portion aligns with said chamber top portion to form an arched chamber in said lid, said one or more inlets are in fluid communication with said drinking hole, and said first snap fitting periphery portion and said second snap fitting periphery portion align for a complete snap fitting periphery of said lid. 
     Preferably, the arched chamber forms an angle of about 5° to about 90° with respect to the radius of the lid. More preferably, the arched chamber forms an angle of about 15° to about 75° and most preferably the angle is about 30° to about 60°. 
     The inlet may be any suitable shape. Most preferably the inlet is either circular or oval. It is most preferred to use two or more inlets in the chamber. 
     It is also preferred that the bottom wall of the chamber be inclined such that liquid in the chamber flows out of the chamber back into the cup through the inlets when the lid is horizontal. 
    
    
     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; 
     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; 
     FIG. 4D illustrates another embodiment of the lid assembly of FIGS. 4A-4C; 
     FIGS. 5A-5B are cross-sections of the lid assembly of the present invention wherein the chamber is primarily made up of the lower lid section and the lid and bottom portion are separate; 
     FIG. 6 is a perspective bottom view of another design for the chamber portion; 
     FIG. 7 illustrates a perspective bottom view of another embodiment of the chamber portion of the present invention; 
     FIG. 8 illustrates a perspective bottom view of yet another chamber design for the lid of the present invention; 
     FIG. 9 illustrates a perspective bottom view of another design for the bottom lid section of the present invention; and 
     FIG. 10 illustrates a top view of the chamber wherein baffles have been employed. 
    
    
     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, moat  13 , drinking hole  14  and air hole  16  extending through, and chamber  18  illustrated as arch-shaped, has top portion  19  and 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 chamber  18  is sunken below the bottom surface of disc  10 . Bottom portion  20  has two inlet openings  21  and  22 . Chamber  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 chamber  18 , through chamber  18  to drinking hole  14  and into the user&#39;s mouth. 
     Bottom section  30  is used to form chamber  18  and a portion of snap fitting periphery  12 . Bottom section  30  comprises arched 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 chamber  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 chamber  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 . In the embodiment shown in FIGS. 4A-4C, projection  52  is on the bottom side of disc  10  and channel  54  is on the bottom section  30 . Alternatively, however, bottom section  30  could have the protrusion and disc  10  could contain the channel. 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  34  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  34  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 two inlets  21  and  22  are illustrated, additional inlets in chamber  18  may be employed. Specifically, there can be inlets in lower end walls  60  and  62  of chamber  18 . Lower end walls  60  and  62  are illustrated in FIG.  2 . Alternatively, one inlet may be used which may be in bottom portion  20  or lower end walls  60  or  62 . 
     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 chamber  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 different sizes, such as 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 simple 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 moat  13  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 chamber  18  may be rounded as shown in FIGS. 1 and 2, or may be rectangular in shape as shown in FIGS. 4A-4C. 
     In FIG. 4D, an identical lid assembly as shown in FIGS. 4A-4C is illustrated, except that in FIG. 4D bottom section  30  is not hinged to disc  10  by joint  38 , hence, joint  38  is absent from FIG.  4 D. 
     As seen in FIGS. 5A-5B, disc  10  is coplanar such that top portion  19  of chamber  18  is coplanar with disc  10 . Drinking hole  14  is positioned in top portion  19  of chamber  18 . 
     Additionally, as shown in FIGS. 5A-5B, bottom section  30  is a separate piece from disc  10 . The embodiment shown in FIGS. 5A-5B, the two pieces, disc  10  and bottom section  30 , are separately molded or, alternatively, have been molded together but have been separated from each other. Additionally, arched side  32  has no snap fitting periphery  34  but, rather, flange  34 ′ that fits into snap fitting periphery  36 ′. Snap fitting periphery  36 ′ is designed to accommodate flange  34 ′. 
     Turning to FIGS. 6-9, alternative embodiments of bottom section  30  and chamber  18  are shown. 
     In FIG. 6, the bottom portion of chamber  18  is shown as a straight tube. 
     In FIG. 7, bottom portion  20  of chamber  18  is shown being perpendicular to the periphery of disc  10 . 
     In FIG. 8, bottom portion  20  of chamber  18  is illustrated as a pillow. 
     In FIG. 9, bottom section  30  is shown as not extending all the way to hole  16 . It can also be seen that bottom wall  40  of chamber  18  is peaked at the center and slanted towards inlets  21 ,  22  to allow fluid to run out of chamber  18  when lid  8  is horizontal. 
     It will be appreciated that top portion  19  is either flat as shown in FIGS. 5A-5B, or is shaped to match bottom portion  20  of chamber  18  as shown in FIGS. 4A-4D. 
     FIG. 10 illustrates a top view of bottom portion  20  of chamber  18  where chamber  18  has one or more baffles  64  positioned therein. Baffles  64  help to prevent spillage. Baffles  64  extend upward from bottom wall  40  and against lower side walls  42  and  44  as shown. Preferably, the height of baffles  64  are equal to the height of side walls  42  and  44 . 
     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.

Technology Category: 7