Patent Abstract:
There is provided a spill proof cup assembly having a cap with at least one spout outlet, a cup with an upper open portion adapted to securely and sealingly receive the cap, and a thermoplastic elastomer, or similar elastomeric material, co-molded bottom portion with a vent disposed therein for allowing air to enter the cup as fluid exits through the spout outlet. The result is a one-way flow of air.

Full Description:
This appln. claims the benefit of prov. appln. No. 60/333,564 filed on Nov. 27, 2001. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a spill proof cup assembly for holding and dispensing drinkable fluids. More particularly, the present invention relates to a spill proof cup assembly having a thermoplastic elastomer (TPE) co-molded bottom with a vent or vent mechanism disposed therein to dissipate the vacuum created as fluid is withdrawn from the cup. 
     2. Description of the Related Art 
     Spill proof cups having caps with a fluid outlet spout and an air inlet vent to permit drinking from the cup without creating an excessive vacuum in the cup, are well known. Further, many of these cups have valving mechanisms, typically coupled with the cap, via the spout and/or the air vent, that respond to the suction generated during drinking to allow fluid to exit the spout and allow air to enter the vent as a vacuum develops in the interior of the cup. 
     Despite the effectiveness of these different cup/cap mechanisms, the applicant has discovered a unique venting mechanism for venting a cup without having a vent located at an upper portion of a cup, without sacrificing the cup&#39;s resistance to spills/leaks, and requiring fewer parts. In addition, the present invention may also allow the cup to be formed of more brittle cup materials. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an improved spill proof cup assembly that is substantially leak-proof. 
     It is another object of the present invention to provide such a spill proof cup assembly having a thermoplastic elastomer (TPE) co-molded bottom with a vent disposed therein. 
     It is still another object of the present invention to provide such a spill proof cup assembly that allows air to flow through the bottom of the cup via the vent to replace the volume of fluid as the fluid is removed. 
     It a further object of the present invention to provide a method of manufacture for a spill proof cup assembly having a TPE bottom with a vent disposed therein. 
     It is yet still a further object of the invention to provide a cup assembly having a soft, cushioned bottom portion for reducing the likelihood of cup breakage, resulting from dropping, and thereby allowing the cup assembly to be comprised of a wider range of materials, including more brittle materials. 
     These and other objects and advantages of the present invention are achieved by a spill proof cup assembly having a cup with an upper open portion and a bottom portion. The bottom portion has a vent disposed therein. The assembly preferably has a cap, with at least one fluid outlet, and adapted to enclose the upper open portion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a cup assembly in accordance with the present invention; 
         FIG. 2  is a side view of the cup assembly of  FIG. 1 ; 
         FIG. 3  is a side section view of the cup assembly of  FIG. 1 , highlighting the cup and co-molded TPE bottom; 
         FIG. 4  is an enlarged view of the cup assembly of  FIG. 3 , highlighting not only the cup component and co-molded TPE bottom but also, vents disposed therein; 
         FIG. 5  is a bottom view of the cup assembly of  FIG. 1 , showing the polypropylene injection molded cup component before it is co-molded with TPE; 
         FIG. 6  is an interior bottom view of the cup assembly of  FIG. 5 ; 
         FIG. 7  is a bottom view of the cup assembly of  FIG. 1 , showing the polypropylene injection molded cup component after it is co-molded with TPE; and 
         FIG. 8  is an interior bottom view of the cup assembly of  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings and in particular  FIGS. 1 through 3 , there is shown a spill proof cup assembly in accordance with a preferred embodiment of the present invention generally represented by reference numeral  1 . Cup assembly  1  preferably has a cup or hollow body  10  with an upper end  20  and a lower end  30 , and a flexible membrane  40  co-molded with lower end  30  to form a unitary container or device. Preferably, hollow body  10  and flexible membrane  40  are made of at least two distinct materials. These distinct materials preferably are polypropylene and thermoplastic elastomer (TPE), respectively. However, other materials such as for example high density polyethylene, polycarbonate, urethane rubber, and silicone may also be used. Further, hollow body  10  can be made of a more clarified, attractive brittle material. 
     Hollow body  10  preferably has an elongated central vertical axis A with an upper end  20  forming an upper opening  22  and a lower end  30  forming a lower opening  32  shown clearly in  FIGS. 5 and 6 . Preferably, upper end  20  selectively cooperates with a cap  24 . Cap  24  preferably having at least one spout or fluid dispensing outlet  26 . Upper end  20  preferably also has threads  21  for engaging corresponding threads  23  of cap  24 . It should be noted, however, that upper end  20  may also be configured without threads such that cap  24  is snap fit over upper end  20 . Preferably, lower end  30 , as shown in  FIGS. 3 ,  4 ,  5  and  6 , has an inner flange  34  preferably running along a lower inner edge  36  of hollow body  10 . Inner flange  34  preferably having one or more apertures serving as mechanical locks  38  when flexible membrane  40  is co-molded to hollow body  10 . 
     Referring generally to  FIGS. 1 through 8 , preferably mechanical locks  38  are arranged such that when flexible membrane  40  is co-molded with hollow body  10 , lower opening  32  is preferably filled with the elastomeric material or TPE and inner flange  34  is preferably sandwiched between two layers of TPE, an upper layer  42  and a lower layer  44 . The result is a flexible membrane defining a vent area  46  that is actuated by differences in pressure. Preferably, mechanical locks  38  are small apertures advantageously situated in inner flange  34  allowing upper layer  42  and lower layer  44  to be connected through the inner flange. 
     Flexible membrane  40 , preferably is soft and provides a cushioning protection for reducing the likelihood of the cup assembly being broken dropped or mishandled. Thus, the co-molding of flexible membrane  40  onto hollow body  10  preferably allows the hollow body to be formed from a more brittle material, which ordinarily would not be usable because of its more fragile nature. Vent area  46 , preferably has one or more dimples or vents  48 . Vents  48  preferably are molded into shape and pierced via a secondary operation. The result is a dimple/pierce that behaves as a pressure actuated valve for allowing air to enter the cup while preventing fluid from leaking out. Vents  48  are preferably positioned as shown in  FIGS. 7 and 8 , with the dimple side facing outwardly from lower end  30 . This configuration is important, as there are mechanical advantages that can be leveraged therefrom. For example, as fluid pushes down on vents  48 , the pressure preferably causes the adjacent surfaces of upper layer  42  and lower layer  44 , which are fashioned by the secondary piercing operation, to be pressed against each other causing vents  48  to close. Conversely, when there is a vacuum within the cup and pressure builds on the outer side of vents  48 , the adjacent surfaces of upper layer  42  and lower layer  44  separate causing vents  48  to open. Thus, the configuration shown in  FIGS. 7 and 8 , preferably facilitates lower end  30  being in compression with vents  48  closed, when there is a positive pressure in the cup, and in tension with vents  48  open, when there is a negative pressure in the cup. This provides the functional performance desired (i.e. a one way flow). 
     Cup assembly  1  is preferably configured to allow air to enter hollow body  10  through lower end  30  via vents  48  to replace fluid being removed from the cup via outlet spout  26  of cap  24 . This helps reduce the vacuum that tends to develop within hollow body  10  as fluid exits during drinking. 
     Cup assembly  1  is preferably formed by injection molding hollow body  10  such that upper end  20  is open and lower end  30  is open with inner flange  34  reducing the cross-sectional area of the lower end opening to be less than that of the upper end opening. Once hollow body  10  is formed, flexible membrane  40  is preferably co-molded to lower end  30  such that the flexible membrane enfolds inner flange  34  and fills lower opening  32  to define vent area  46 . 
     The present invention having been thus described with particular reference to the preferred forms thereof, it will be obvious that various changes and modifications may be made therein without departing from the spirit and scope of the present invention as defined herein.

Technology Classification (CPC): 0