Abstract:
An illuminated drinking vessel includes a main body with a side wall having fluorescent pigment. An ultraviolet light-emitting diode illuminates the fluorescent pigment. The drinking vessel includes an electrical power source such as a button cell and an electrical switch for selectively controlling the flow of electrical current between the power source and light-emitting diode. A base member connected to the main body contains the power source, the electrical switch, and the ultraviolet light-emitting diode. The fluorescent pigment of the side wall emits visible light in response to being illuminated by ultraviolet light.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates to drinking vessels, and particularly to drinking vessels having a self-contained source of illumination.  
           [0002]    It is known to provide a drinking vessel with a self-contained source of illumination to light the drinking vessel in the dark. Lighted drinking vessels commonly include a lamp of the light-emitting diode (LED) or incandescent type, a battery, and an electrical switch and circuit to control the flow of current between the battery and the lamp.  
           [0003]    Illuminated drinking vessels have been an object of interest for more than fifty years, as exemplified by the following patents:  
                                       Patent No.   Inventor   Issue Date                   2,224,319   Schroyer   Dec. 10, 1940       2,663,866   Simpson   Aug. 23, 1951       4,390,928   Runge   Jun. 28, 1983       4,922,355   Dietz et al.   May 1, 1990       5,070,435   Weller   Dec. 3, 1991       5,119,279   Makowsky   Jun. 2, 1992       5,211,699   Tipton   May 18, 1993       5,339,548   Russell   Aug. 23, 1994       5,504,663   Tucker   Apr. 2, 1996                  
 
         SUMMARY OF THE INVENTION  
         [0004]    The present invention provides an illuminated drinking vessel including a lower wall, and a side wall having fluorescent pigment. An ultraviolet light-emitting diode is proximate the lower wall to illuminate the fluorescent pigment. The drinking vessel further includes an electrical power source and an electrical switch for selectively controlling the flow of electrical current between the power source and light-emitting diode.  
           [0005]    Other aspects of the present invention will be apparent from the following description of preferred embodiments with reference to the accompanying drawings.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    [0006]FIG. 1 is a side view of one embodiment of an ultraviolet illuminated drinking vessel with a wall having fluorescent pigment, shown in cross-section.  
         [0007]    [0007]FIG. 2 is an exploded view of the drinking vessel of FIG. 1.  
         [0008]    [0008]FIG. 3 is a top view of the printed circuit board shown in FIGS. 1 and 2.  
         [0009]    [0009]FIG. 4 is an electrical schematic of the flasher circuit in the drinking vessel of FIGS. 1 and 2.  
         [0010]    [0010]FIG. 5 is a side view of another embodiment of an ultraviolet illuminated drinking vessel with a wall having fluorescent pigment, shown in cross-section.  
         [0011]    [0011]FIG. 6 is an exploded view of the drinking vessel of FIG. 5.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0012]    For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.  
         [0013]    Referring to FIG. 1 as well as to the exploded view of FIG. 2, one embodiment of the present invention is a lighted drinking vessel or shot glass  10  that includes a main body  12  and a base member  14  which are molded separately and which enclose an impact-responsive indicator circuit  16 . Main body  12  includes an integral lower wall  18  and side wall  20  that define a receptacle for liquid and that cooperate with base member  14  to form a hollow base. Walls  18  and  20 , together with a side wall  22  and a bottom wall  24  of base member  14 , define a compartment  26  for the indicator circuit. Main body  12  is frustoconical and base member  14  is generally cylindrical as illustrated, but either one may have either shape. The main body and base member are both preferably molded of high-impact polystyrene. Further details on a shot glass of the type described above may be found in U.S. Pat. Nos. 5,772,065 to Kalamaras, which patent is hereby incorporated by reference.  
         [0014]    Main body  12  is constructed of a transparent or translucent molded plastic material and is illuminated by a light source, which may be flashing or blinking, located within base member  14 . As preferred, the plastic material of at least side wall  20  and preferably all of main body  12  has fluorescent pigment mixed therein prior to molding. In an alternative configuration that may be desirable for some applications, the fluorescent pigment may be applied as a coating to the outer surface of the side wall  20 . The light source within base member  14  is an ultraviolet light emitting diode (UV LED). The ultraviolet light excites the fluorescent pigment and causes the main body  12  to glow, creating a novel and pleasing aesthetic effect, and also illuminating adjacent surfaces in low-light conditions.  
         [0015]    The fully assembled shot glass of FIG. 1 has an overall height of about 55-60 mm. As shown in the drawing, the floor of compartment  26  is 1.5 mm below the bottom edge  28  of side wall  20 , and the ceiling is 9.5 mm above edge  28 , for a total inside height of 11 mm. Although these are the preferred dimensions, it will be understood that some variation thereof is contemplated for any given size of shot glass and that other sizes of shot glasses are contemplated. Indicator circuit  16  in the disclosed embodiment has an overall height of about 8 mm.  
         [0016]    The separately molded parts of the shot glass may be adhesively bonded together or may be attached by means of a snap-fit connection. In one form of snap-fit connection, the inner surface of side wall  20  is provided with an annular projection or ridge and the outer surface of side wall  22  is provided with a corresponding annular groove, or vice versa. The ridge may extend completely or partially around the circumference of the side wall  20 , and in this case there may be a set of circumferentially spaced ridges. Alternatively, the mating side wall surfaces may both be provided with annular projections adapted to momentarily compress or bend each other as one is forced over the other to snap the two parts of the shot glass together. As another alternative, a set of circumferentially spaced interlocking projections may be provided on each of side walls  20  and  22  and arranged such that the respective projections in each set are offset from each other circumferentially for insertion of the base member into the main body and then rotated with respect to each other in “bayonet” fashion to achieve mutual locking engagement. Although not preferred, the base members may alternatively be joined by ultrasonic welding, in which case energy-directing beads may be required on the mating surfaces as described in the above-referenced U.S. Pat. No. 5,772,065.  
         [0017]    Referring now also to FIGS.  3 - 4 , the indicator circuit in the illustrated embodiment is a flasher circuit and includes a low-profile inertial switch  30  having a cantilevered coil spring contact  32  directly mounted on a printed circuit (pc) board  34  and oriented with the longitudinal axis of the coil spring parallel to the plane of the pc board and perpendicular to the longitudinal axis of the shot glass. The flasher circuit includes inertial switch  30 , an integrated circuit (IC)  36 , an ultraviolet (UV) LED  38 , two button cells  40   a,b  in respective battery holders  42   a,b,  and associated resistors  44  and  46 , all interconnected as shown in FIG. 3 and all mounted on the circuit board, which may be secured to lower wall  24  by double-backed tape. Suitable dimensions for the pc board are 0.8 mm thickness and 23 mm diameter. The inertial switch as shown is a normally open switch, and IC 36 is triggered by closure of the switch to supply a flashing signal to the UV LED. The IC preferably operates in one-shot mode, whereby it continues to generate an output signal once triggered by the switch, and preferably generates a train of pulses in response to a trigger pulse from the switch.  
         [0018]    The IC is preferably supplied in die form and wire bonded to the upper surface of the circuit board. A suitable IC for the flasher circuit is type HKA-5417, also identified as A5417, commercially available from Hua Ko Electronics Co. Ltd., Hong Kong. The IC generates a pulse train of 38 pulses each time it is triggered, at a rate and with a pulse width controlled by timing resistor  46 . The timing resistor value is preferably selected so that the IC generates approximately 2 pulses per second with a pulse width of approximately 100 milliseconds. Proportionately different pulse widths and rates may be obtained if desired by selecting a different value for resistor  46 . Further details of a suitable circuit design may be found in U.S. Pat. No. 6,419,384 to Lewis et al., which patent is hereby incorporated by reference.  
         [0019]    UV LED 38 emits light having a wavelength in the range of about 390 to about 410 nm, more preferably having a peak of about 390 nm to about 410 nm, and most preferably having a peak of about 400 nm. A suitable UV LED is the DL50PLDW503 UV LED available from Shue Kwong Optic Electronic Company, Shenzhen, China. The ultraviolet light is collected by lower wall  18  and transmitted throughout the plastic material that comprises lower wall  18  and side wall  20  of main body  12 . The intensity of the illumination may diminish somewhat along the length of side wall  20 , due to increased attenuation of the ultraviolet light as it passes through the plastic material, resulting in the brightness of the visible light emitted from side wall  20  diminishing over the length of shot glass  10  toward the rim. The visual effect may be enhanced, if desired, with an upwardly oriented parabolic or otherwise curved reflector around the UV LED. A flat reflector is also useful around the LED.  
         [0020]    The above-described combination of a UV LED and fluorescent pigment in a shot glass is particularly advantageous with a dark alcoholic beverage or other liquid in the glass. Dark liquids tend to absorb the light emitted from a light source in the base and thereby degrade the illumination. However, UV light transmits through the dark liquid and/or through the plastic body of the shot glass and, in combination with the fluorescent pigment, causes the side wall to glow and thereby remain highly visible despite the contents of the glass.  
         [0021]    The plastic material of side wall  20  and lower wall  18  can be a polycarbonate material that is mixed with fluorescent pigment and injection molded into the shape of shot glass  10 . Alternatively, the plastic material may be polystyrene, PVC, ABS or acrylic materials. The pigment may be mixed at a ratio of about 1 to 2 grams of pigment per kilogram of plastic material. The fluorescent pigment may be a pigment that is commercially available from Wen Lee Plastic Pigment Company, Tungguong, China, such as Part No. 61113 (green), Part No. 31461 (blue), Part No. 238 (red), or Part No. 2600 (yellow). As discussed above, in an alternative configuration that may be desirable for some applications, the fluorescent pigments may be applied as a coating to the outer surface of the side wall  20 .  
         [0022]    An alternative circuit configuration suitable for certain applications including larger drinking vessels such as tumblers is disclosed in copending U.S. patent application Ser. No. 08/730,597 and is incorporated herein by reference. In addition, the invention may alternatively be embodied in plastic mugs and miniature martini glasses.  
         [0023]    Another embodiment of the present invention is shown in FIGS. 5 and 6 in which drinking vessel or shot glass  110  is similar to shot glass  10  described above, except as further described below. Shot glass  110  has an overall height of about 76 mm and a maximum diameter of about 36 mm, and is frustoconical but with a shallower taper than that of shot glass  10 . Main body  112  and base member  114  together enclose an impact-responsive indicator circuit  116  of the same type as circuit  16  described above. Main body  112  is preferably bayonet mounted to base member  114 , i.e., by means of a press- and-twist interlocking connection. More specifically, the bottom portion  128  of side wall  120  may have two small projections engaging respective L-shaped grooves formed in the inside surface of side wall  122 . Other types of connections as described above for shot glass  10  may be employed as alternatives.  
         [0024]    While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. For example, it is also contemplated that fluorescein dye may be mixed with ink to be applied to a surface of the main body of the drinking vessel to form a logo or other indicia desired to be illuminated.