Abstract:
A drinking cup has a cover which is formed with a drinking spout at one side and a vent at the other. Elements extend down from under the spout and the vent. A flow control element is provided and made of elastomeric material having a pair of spaced cavities on one side, each cavity having a floor at the bottom thereof. The cavities receive in frictional engagement respectively the lower ends of the elements. This engagement supports the flow control element with the floor of each cavity in sealed relation to its element. Each floor has a passage which is normally closed but opens on the occurrence of a pressure differential on opposite sides of the floor.

Description:
FIELD OF THE INVENTION 
     This invention relates to a covered drinking cup of the type often used by infants and children as a training cup because it safeguards against spills and provides liquid flow through a nipple-like spout. More specifically, this invention relates to covered drinking cups that provide a leak-proof flow of the liquid and venting of the head space as liquid is withdrawn. 
     BACKGROUND OF THE INVENTION 
     In the past nursing bottles and cups for dispensing milk and other liquids to infants and children have often been in the form of vented covered containers. For instance, U.S. Pat. No. 2,372,281 to Jordan, which issued on Mar. 27, 1945, has a cover that provides a nipple on one side having flow-regulating means and a vent on the other side also having flow-regulating means. By adjusting the two flow-regulating means, the user can comfortably draw liquid from the nipple. As the liquid is withdrawn, air moves in through the vent to replace the withdrawn liquid and prevent negative pressure build-up which in the extreme can stop liquid flow. 
     Another covered drinking cup is disclosed in U.S. Pat. No. 2,608,841 to Rice which issued on Sep. 2, 1952. As the venting means, the Rice cup provides a manually adjustable valve which controls the ease with which air is admitted into the cup for venting. It thereby regulates the flow of liquid. 
     With respect to the admission of air into nursing bottles and the like, check valves have often been used and are disclosed in the U.S. Pat. Nos. 4,401,224 to Alonso which issued on Aug. 30, 1983; 4,545,491 to Bisgaard, et al. which issued on Oct. 8, 1985; 4,723,668 to Cheng which issued on Feb. 9, 1988; and 4,828,126 to Vincinguerra which issued on May 6, 1989. 
     Other vent means are disclosed in U.S. Pat. No. 4,865,207 to Joyner, et al. which issued on Sept. 12, 1989 in which a fabric hydrophobic filter passes air into the nurser. 
     U.S. Pat. No. 4,135,513 to Arisland, which issued on Jan. 23, 1979, discloses a drinking nozzle for a nursing bottle which incorporates air venting means, opening a valve when the pressure within the container is substantially less than atmospheric pressure to thereby vent the head space. 
     U.S. Pat. No. 5,079,013 to Belanger, which issued on Jan. 7, 1992, discloses a dripless liquid feeding/training container in which the cover is provided with two spring-biased check valves. One check valve is a spring biased ball check that permits inward air flow for venting and the other check valve is a spring-biased outlet valve that opens by the sucking action of the infant and springs closed when the sucking action relents. The container is described as “dripless”. 
     One of the shortcomings of some of the prior art is that the valves involved have metal parts. Further, the number of the parts involved makes such containers difficult to manufacture, assemble and clean. There is, hence, a need for a less complicated structure that eliminates the metal parts, and is readily washable. It is to such a need that the present invention is directed. In a preferred embodiment, the control element has additional means to retainer it in place in the cup even during impact. 
     SUMMARY OF THE INVENTION 
     The present invention is a control element for a drinking cup, and the drinking cup in which the cover has a drinking spout at one side and a vent at the other. Tubular elements extend down from under the spout and the vent. The flow control element of elastomeric material is provided having a pair of spaced cavities on one side, each cavity having a floor at the bottom thereof. In assembly, the cavities receive in frictional engagement the lower ends of the tubular elements. This engagement supports the flow control element with the floor of each cavity in sealed relation with respect to its tubular element. Each floor has a passage that is normally closed but opens on the occurrence of a pressure differential on opposite sides of the floor. 
     In a preferred embodiment, the control element includes a pair of shoulders that assist in maintaining the control element in place even during impact. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further objects and features of the present invention will be apparent to those skilled in the art from a study of the following specification and the accompanying drawings, all of which disclose a non-limiting embodiment of the invention. In the drawings: 
     FIG. 1 is a perspective view of an assembled drinking cup that embodies the invention; 
     FIG. 2 is an enlarged perspective view of a first embodiment of the flow control element of the invention; 
     FIG. 3 is a top plan view of the flow control element of FIG. 2; 
     FIG. 2 is an enlarged fragmentary sectional view taken on the line  4 — 4  of FIG. 1; 
     FIG. 5 is an enlarged perspective view of a second embodiment of the flow control element of the invention; and 
     FIG. 6 is an enlarged fragmentary sectional view taken on the line  4 — 4  of FIG. 1 of the flow control element of the second embodiment of FIG.  5 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the drawings and, in particular, FIG. 1, a drinking cup that embodies the invention is generally represented by reference numeral  10 . The drinking cup  10  comprises a cup-shaped container  12  having a cover  14  that may be screwed on to the top of the container by cooperant threads shown in FIG.  4 . The cover  14  comprises a top wall  16  and a depending downward or side wall  18  formed with interior threads that engage exterior threads about the mouth of the container  12  as described. 
     Just inside the downward wall  18 , the cover  14  may be provided with a short annular wall  20 . Also, an O-ring (not shown) may be disposed in between the annular wall  20  and the side wall  18  of the cover  14 . The O-ring may be compressed to form a liquid sealing joint between the cover  14  and the container  12 . 
     One side of the top wall  16  is provided with a drinking spout  22  which has dispensing openings  24  at its distal end. Formed unnaturally with the cover  14  and extending downward from the spout  22  inside the cover is an element  26 . In the embodiment shown in FIG. 1, the spout  22  and element  26  are tubular elements, however these elements can be any geometric shape. It is important that the spout  22  and element  26  communicate into liquid tight engagement. Therefore, the spout  22  and element  26  preferably have holes therethrough of the same shape. 
     At the opposite side of the top wall  16 , the cover  14  is provided with a vent  28 . Formed unnaturally with the cover  14  is a downward element  30  which communicates with the vent  28 . In a preferred embodiment, element  30  is tubular in shape, however it can also be any shape. It is also preferable, that the since the vent  28  and element  30  have air tight communication between each other, that they have holes therethrough of the same shape. 
     Both elements  26  and  30  terminate downwardly at the same level in downwardly facing openings. In the preferred embodiment, both elements  26  and  30  are tubular or cylindrical. Since element  26  communicates with the spout  22 , while the element  30  communicates with the vent  28 , the diameter of element  26  is preferably larger than the diameter of element  30 . However, it is understood that the diameter of the holes of each element  26 ,  30  can be any size and shape depending on the size and shape of the spout  22  and vent  28 , respectively. 
     As shown in FIG. 2, there is provided a flow control element  40 . It is preferably a single piece of elastomeric material, such as, for example, thermoplastic elastomer, silicone, or a soft rubber. The elastomeric material is resilient and flexible and does not have any separate parts, such as balls and springs. The control element  40  has a pair of spaced cavities  42 ,  44  formed in one side. The pair of spaced cavities  42 ,  44  are formed near opposite ends  41  of the control element  40 . The cavities  42 ,  44  can have any shape, however they should have a shape that complements the shapes of elements  26 ,  30 , respectively. Therefore, in a preferred embodiment, cavities  42 ,  44  should have a tubular or circular shape. Each cavity  42 ,  44  has a one or any number more of ribs  50 ,  52 , respectively. In the preferred embodiment, each cavity  42 ,  44  has two ribs. These ribs  50 ,  52  act to seal the cavity  42 , 44  to the respective element  26 ,  30 . 
     Also, cavity  42  complements element  26  that communicates with spout  22 , and cavity  44  complements element  30  that communicates with vent  28 . Accordingly, in the preferred embodiment, the cavities  42 ,  44  are cylindrical. Furthermore, the diameter of cavity  42  is greater than the diameter of cavity  44  due to the difference in the diameters of the spout  22  and the vent  28 . For example, in an embodiment in which the elements  26 ,  30  are cylindrical and with conventional, different diameters, cavity  42  has a rib diameter about 0.57 inches and a flat (the area between ribs) diameter about 0.63 inches, whereas cavity  44  has a rib diameter about 0.50 inches and a flat diameter about 0.55 inches. 
     In the preferred embodiment, the spout  22  is closer to side wall  18  than vent  28 . Accordingly, as shown in FIG. 4, the cavity  42  is closed to edge  41  than cavity  44  is to respective edge  41 . It should be understood, however, that if the relationship of the spout  22  and vent  28  to side wall  18  varies so does the relationship of the cavities  42 ,  44  to edge  41 . Accordingly, cavities  42 ,  44  can be equidistant from respective edges  41 , or cavity  44  can be closer than cavity  42  to respective edge  41 . 
     The control element  40  is formed with floors  46 ,  48  at the bottom of each cavity  42 ,  44 , respectively. As stated above, extending inward from the sides of each cavity  42 ,  44  are, in a preferred embodiment, a pair of spaced horizontal inward circumferential ribs  50 ,  52 , respectively. In particular, cavity  44  has a pair of ribs  50 , and cavity  44  has a pair of ribs  52 . As also stated above, each cavity may have any number of ribs. The ribs  50 ,  52  secure the control element  40  onto elements  26 ,  30 , respectively, by frictional engaging the exterior walls of the elements. It is preferred that the lowermost one of the pair of ribs  50  in cavity  46  not contact floor  46 , and likewise the lowermost one of the pair of ribs  52  in cavity  44  not contact floor  48 . By this feature, the least amount of tension is placed on the control element  40  during use. By minimizing this tension, the sealing characteristics of the slit is optimized. 
     Referring to FIGS. 3 and 4, the floors  46 ,  48  are formed with slits  54 ,  56 , respectively. The slits  54 ,  56  can have many forms, two of which are “Y”- or “X”-shaped slits for the passage of fluid. Preferably, one slit  54 ,  56  in each floor  46 ,  48 , respectively, is sufficient to facilitate the passage of liquid in element  26  and the passage of air in element  30 . However, multiple slits in each floor may be designed to provide the same function. 
     In the assembly shown in FIG. 4, the two cavities  42 ,  44  are aligned with the two, preferably tubular, elements  26 ,  30  and the control element  40  is raised. The elastomeric nature of the control element  40  is sufficient to flex as the control element is effected. The control element  40  is then shoved “home” on each element  26 ,  30  so that the lower ends of the elements abut against the floors  46 ,  48 , respectively and effect therewith a snug contact that amounts to a seal, especially in view of ribs  50 ,  52  frictional contact on elements  26 ,  30 , respectively. Slight imprecision in the dimensions of the cavities  42 ,  44  or of the control element  40  can be tolerated due to the soft resilient nature of the control element and, perhaps, the ribs  50 ,  52 . 
     After the container  12  is filled with liquid, the cover  14  is screwed onto the container. As the infant tilts the container and sucks liquid through the openings  24 , the slits  54  yield and part in the center of the slits. When the sucking pressure relents, the resilience of the cavity  42  causes the slit  54  to close once more so that were the cup  10  to be tipped over or to fall on the floor, no appreciable liquid would pass out the openings  24 . 
     As the liquid is removed as by sucking on spout  22 , a negative pressure builds up in the head space above the liquid. To avoid this pressure—pressure differential across the floor  48 —becoming too great, the slits  56  yield, the centers moving downward to permit passage of atmosphere through the opening  28  and through the slits. When the pressure differential is substantially returned to zero, the resilience of the control element  40  causes the slits to close so that should an upset occur, no liquid could escape outwardly therefrom through vent opening  28 , and a leak through that route is avoided. 
     Referring to the second embodiment of FIGS. 5 and 6, the same elements recited above will bear the same reference numeral except with a prime. As shown in FIG. 5, the control element  40 ′ includes a pair of shoulders  62 ,  64  adjacent the opposite ends or edges  41 ′ of the control element, and extending in a direction opposite the opening of each cavity  42 ′,  44 ′. Each shoulder  62 ,  64  has a surface configuration analogous to that of the ends  41 ′. 
     As shown in FIG. 6, in the most preferred embodiment, each shoulder  62 ,  64  has a portion  66  that may be either straight or chamfered and an inwardly chamfered or angled portion  67 . The chamfered portion  67  is adapted to mate with the inside surface of the side walls  18 ′ of the container in order to prevent the control element from disengaging elements  26 ′ and  30 ′. In a preferred embodiment, the chamfered portion  67  may be at angle of about seventy-seven degrees with the vertical, straight portion. 
     In the most preferred embodiment shown in FIG. 6, each shoulder  62 ,  64  has a vertical extant of the valve and shoulder about 0.54 inches. The vertical extant of each shoulder  62 ,  64  is affected by its distance from edge  41 , which as stated above is dictated by the position of spout  22 ′ and vent  28 ′ from the side wall  18 ′ of the container. 
     It is understood that the shoulders  62 ,  64  can consist solely of a straight portion, an outwardly angled, an inwardly angled portion or any combination of same depending on the angle of the walls of the container  12 . In addition, the shoulders  62 ,  64  can have any shape. The sole criteria is that is mates with the inside of the side walls  18 ′ of the container to help prevent the control element  40  from disengaging the elements  26 ′,  30 ′. The pressure for the control element  40 ′ to dislodge particularly occurs when the control element  40 ′ is forced away from the spout and vent of the cover upon impact. 
     In either embodiments, after use, the cup  10  of the invention may be readily disassembled. Referring to FIG. 1, the cover  14  may be removed and the control element  40  simply withdrawn off the elements  26 ,  30 . All of the components are readily washable. 
     It will be seen that the invention provides a training cup of three simple parts which is inexpensively and readily made and assembled and works effectively to avoid spills and drips. 
     The invention described here may take a number of forms. It is not limited to the embodiment disclosed but is of a scope defined by the following claim language which may be broadened by an extension of the right of exclude others from making, using or selling the invention as is appropriate under the doctrine of equivalents.