Abstract:
A device and method for illuminating a fluid is disclosed. The device includes a closed, collapsible container for holding a fluid and having an outlet, a light source for illuminating the fluid being dispensed through the outlet, and a switching mechanism for activating the light source in response to an external event, such as a change in pressure within the container, fluid pressure, and the like. The container may be a portable, hand-held container, such as a toothpaste dispenser, shampoo container, and the like.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to illumination devices, and more specifically to devices that illuminate a fluid that is dispensed from a collapsible, closed container 
       BACKGROUND OF THE INVENTION 
       [0002]    It is well known that a column of transparent fluid acts as a light pipe when a light source is directed axially into it. Such a column will conduct light through its interior in much the same way that a fiber optic cable does, in an effect known as total internal reflection. Unlike a fiber optic cable however, a typical fluid column contains ripples, voids, and other imperfections throughout its interior. As a result, some light is scattered outward rather than being conducted through it. This scattered light causes the fluid column itself to glow. 
         [0003]    This effect has been employed to create illuminated water fountains that appear to project arcing beams of light into the air. An example of such a device is described in U.S. Pat. No. 6,076,741. This effect has also been used to illuminate a stream of water as it emerges from a plumbing fixture such as a bathroom faucet, as disclosed in US Published Application No. 2004/0258567A1, and has similarly been used to illuminate a beverage emerging from a tap. 
         [0004]    Furthermore, this effect has been used to illuminate the interior of a container so that the fluid within becomes luminescent, as shown in U.S. Pat. Nos. 6,352,352 and 6,254,247 and U.S. Published Application No. 2003/0137827A1. 
         [0005]    Therefore, it is clear that many devices exist that will illuminate a stream of fluid being projected from a fixture, and likewise, that cause a static body a fluid within a vessel to glow. However, none of these devices are intended to cause a column of fluid to glow when dispensed from a hand-held, collapsible closed container. 
       SUMMARY OF THE INVENTION 
       [0006]    Many everyday activities, such as grooming and brushing teeth, involve the use of transparent or semi-transparent fluids. These fluids are frequently dispensed into the hand or onto some implement, from a container. There would be considerable utility and novelty value in rendering such fluids luminescent while they were being dispensed, so that, for example, a line of toothpaste could glow while being applied to a tooth brush, or a pool of hair gel could glow while being dispensed into the palm. 
         [0007]    It is therefore an aspect of the invention to provide a general and widely adaptable container that can render a fluid luminescent during the dispensing process, with the dispensing process being defined as the state in which the fluid is external to, yet still in contact with, the outlet of the dispensing container. 
         [0008]    The invention is an illuminated fluid dispensing container which conducts light through the dispensed fluid using the effect of total internal reflection, whenever a continuous column of fluid exists between the outlet of the container and the fluid already dispensed. The invention thereby renders the dispensed fluid luminescent. In effect, the device uses the dispensed fluid to form what is commonly known as a “light pipe”. 
         [0009]    The light source may be located within the container or outside of the container. If the light source is located outside of the container, a reflective conduit is used to conduct the light to the interior of the container. 
         [0010]    The light source may be either electrical or chemical. Where the light source is electrical, a switch may be provided to activate the light while the fluid is being dispensed. 
         [0011]    The device may function using any clear, or semi-clear fluid, including solutions, suspensions, gels, and slurries. 
         [0012]    The essential elements of the device include a light source, power for the light source, and a means for activating the light source while fluid is being dispensed. The device primarily resides at, or near, the outlet of a container. While the presence of a container is not essential to the function of the device, all descriptions of the invention are made in context of the device being used in conjunction with a closed container. This container dispenses the fluid that is subsequently illuminated. 
         [0013]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
           [0015]      FIG. 1  is a side view of the preferred embodiment of the invention. 
           [0016]      FIG. 2  is a side view schematic showing the position of the light source relative to the container. 
           [0017]      FIG. 3  is a side view schematic showing an alternative position for the light source. 
           [0018]      FIG. 4  is a side view schematic showing yet another position for the light source. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0019]    The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
         [0020]    Referring now to  FIG. 1 , the device uses a light source  10 , such as a high-intensity LED. The light source  10  is located near an outlet  12  of a container  14 , and is positioned so that light source  10  projects light generally toward the outlet  12 . The light source  10  is powered by a power source  16 , such as a battery, and the like. In one embodiment, electrical current from the battery  16  is controlled by a pressure sensitive tape switch  18 . 
         [0021]    In operation, the LED  10 , or other light source, emits light when fluid is being dispensed from the container  14 , and not during other times, such as when the container  14  is being stored. In one embodiment, the pressure sensitive tape switch  18  is attached to the wall of the container  14  in such a location that the switch  18  is placed in a closed state when the container  14  is grasped or squeezed with the hand, thereby activating the light source  10 . In another embodiment, the light source  10  may be activated via a pressure sensitive switch located within the closed container  14  to sense a change of pressure within the closed container  14  due to the user squeezing the container  14 . Once the user releases the container  14 , the pressure in the container  14  will reach an equilibrium pressure state and the light source  10  will be deactivated. 
         [0022]    Once the fluid  20  has begun to flow from the container&#39;s outlet  12 , the light rays emitted from the LED  10  are conducted through the interior of the fluid  20  by the effect of total internal reflection. Due to the light-scattering effect noted previously, the fluid column subsequently becomes luminescent, or glows, for some distance after exiting the container  14 . The actual length of fluid  20  that may be illuminated in this way depends on the intensity of the LED  10  and the transparency of the fluid  20 . 
         [0023]    In an embodiment, the fluid  20  is in direct contact with the LED  10 , and flows around the LED  10 . Because LEDs are hermetically sealed against moisture during manufacture, fluid contamination is not a concern. However, if desired, the LED  10  and its wires may be encased in a clear plastic sheath with little effect on light transmission. 
         [0024]    It is important to note that light does not simply project straight outward from the container as with a flashlight. Instead, the majority of the light is captured by the fluid column as the light emerges from the outlet  12  of the container  14 , and is bent to follow the path of the fluid  20 , thereby creating the illusion that the fluid  20  emerging from the container  14  is glowing. This effect may be sustained as long as the column of fluid is in contact with the outlet  12  of the container  14 . 
       Alternative Embodiments 
       [0025]    As noted previously, it is preferable that the light source  10  is only active during the time that fluid  20  is being dispensed from the container  14 . While it is currently believed that the most economical and effective way to achieve this by using a pressure sensitive switch  18  on the wall of the container  14 , there are other means of activating the light source  10  during the dispensing process which may later be adopted as an alternate embodiment of the invention. Some of these alternate embodiments are described below. 
         [0026]    Tilt Sensor 
         [0027]    Since it may safely be assumed that the user will tilt the container downward while dispensing fluid, it may be preferable to use a tilt sensor to control the light source  10 . This sensor would activate the light source  10  when the container  14  was tilted some degree past horizontal. A means would be necessary to deactivate the sensor during transportation of the container  14 . 
         [0028]    Activation Upon Removal of a Cap 
         [0029]    Nearly all fluid containers require that some sort of closure or cap be removed prior to dispensing their contents. It may be preferable use this action to also activate the light source  10 . This can be accomplished by linking an electrical switch to the cap so that it closes when the cap is removed and opens when the cap is replaced. 
         [0030]    Manual Activation by Momentary Button or Switch 
         [0031]    It may be sufficient to simply require the user to manually hold down a momentary button or switch while the container was being used. 
         [0032]    Hydrostatic Pressure Sensor 
         [0033]    When dispensing highly viscous fluids such as toothpaste, it is necessary to squeeze the container  14 . The resulting increase in hydrostatic pressure within the container  14  can be detected with a pressure sensor, which could activate the light source  10 . 
         [0034]    Other means may exist to activate the light source  10  during the dispensing process, and this description is not intended to limit the invention to any particular mechanism. 
         [0035]    Location of the Light Source 
         [0036]    As mentioned previously, the preferred embodiment puts the fluid in direct contact with the LED  10 , which is immersed in the fluid stream. This configuration is illustrated by  FIG. 2 . Here, a generic light source  22  is located within a container  14 , and directs its light generally toward the container&#39;s outlet  24 . 
         [0037]    Alternatively, as shown in  FIG. 3 , the light source  26  may be located outside of the container  14 , with the light rays being conducted into the container  14  through a reflective or conductive structure  28 . 
         [0038]    Yet another method for implemented an external light source is shown in  FIG. 4 . Here, the light source  30  projects through a clear window  32  located behind the outlet  34  of the container. 
         [0039]    It can readily be shown that the essential function of this invention does not rely on the specific means by which light is generated. Therefore, this invention should not be limited to using a Light Emitting Diode (LED), but instead may function equally well with an incandescent, fluorescent, or other type of electric lamp. Furthermore, this invention is not limited to using an electrically powered light, but may employ a chemically powered light source as well. 
         [0040]    Other Operational Considerations: 
         [0041]    Due to the wet environment in which the invention will likely be used, it is preferable that the electronic system be sealed. To facilitate this, it may be preferable to employ a non-opening battery compartment, in which case the device would be disposed of when the batteries were exhausted. 
         [0042]    It may be determined that it is more practical to market the invention as an accessory designed to fit onto an existing container, rather than as a complete dispensing system. This may be preferable with a product such as toothpaste, where many manufactures use a common closure or cap size. In this case, the invention would take the form of a large cap that would contain all the components necessary to power and activate the light. 
         [0043]    The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.