Abstract:
An ultrasonic fog generator creates a fog of a liquid such as water. The visual appearance of the fog may be altered such as by being illuminated by one or more lights having one or more colors. Further, the fog may be used to deliver pharmaceuticals to one or both of the lungs of a patient.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Chinese Design Patent Application Serial Nos. ZL 01-3-53634.6 (Certificate No. 255801), ZL 01-3-53635.4 (Certificate No. 253978), and ZL 01-2-58009.0 (Certificate No. 515796), all of which were filed on Nov. 16, 2001. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to creating fog, which may be in the form of mist. More particularly, the invention relates to using fog or mist in a visually appealing display or as a conduit for drug delivery. 
     2. Description of the Related Art 
     There are generally four types of visual vapor or fog generators on the market today. Carbon dioxide (“CO 2 ”) fog generators generate a visual fog using a solid block of CO 2  (i.e., dry ice) which is dropped into a bath of deionized (“DI”) water heated to 140° F. or higher. One disadvantage of CO 2  fog generators is that the fog quantity they produce is unregulated, i.e., the fog quantity cannot be readily applied in any situation without adjusting the size of the of CO 2  block as the quantity of fog produced is largely based on the size of the block used. Further, in applications requiring a large amount of fog, the size of the CO 2  fog generator can become large and cumbersome. In addition, as the CO 2  block melts, the quantity of fog output from the fog generator diminishes and the temperature of the DI bath is lowered which, in time, will require a reheating of the water or adding more hot water thereto. Further, when the CO 2  block melts, it must be replaced by another costly CO 2  block. 
     Helium bubble generators, as the name implies, generate small helium filled bubbles of water that float in the air at almost neutral buoyancy. Unfortunately, helium bubble generators tend to produce a small quantity of bubbles that may fail to create a dense and realistic fog. Further, increasing the helium levels in a room may have a negative impact on the comfort of people in the room. 
     A third type of fog generator generates a fog by passing steam from boiling water through a bath of liquid nitrogen (“N 2 ”) creating a super cooled fog. Similar to the CO 2  block fog generator, liquid N 2  fog generators tend to be large and require a continuous supply of costly of liquid N 2 . Further, these fog generators may be hazardous because they require both a boiler to heat the water and extremely cold liquid N 2  to operate. 
     Finally, ultrasonic fog generators create fog by vibrating a bath of water using ultrasonic sound. The fog may be disbursed through a long hose in which water vapor fog may condense. 
     One common fact among the aforementioned fog generators is the creation of fog in a way that fails to be visually pleasing, i.e., the only thing created is fog. In addition, the fog created serves no purpose other than perhaps being indicative of airflow and simulating fog. 
     SUMMARY OF THE INVENTION 
     The invention herein contains multiple embodiments including a housing for an ultrasonic fog generator. In this embodiment, the housing includes a transducer and a visually appealing display. The transducer is adapted to vibrate ultrasonically. When the housing is positioned in a source comprising a liquid and when the transducer vibrates ultrasonically, the housing is adapted to create a fog from the liquid in the source; the fog emanates from the liquid source. The visually appealing display is adapted to alter an appearance of the fog. 
     In a further embodiment of the housing, the housing may be adapted to be hand-held. 
     In another further embodiments of the housing, the liquid may be water. 
     In another further embodiment of the housing, the fog may be in the form of a mist. 
     In other further embodiments of the housing, the housing may addition include a sensor. Further, the sensor may be adapted to monitor a property of the liquid contacting the housing. In addition, a current control system may be adapted to stop vibration of the transducer in response to the monitored property. 
     In other further embodiments of the housing, the visually appealing display may include at least one light. Further, the visually appealing display may include at least two lights, wherein the lights are adapted to radiate light of at least two different colors. In addition, the colors which the lights are adapted to radiate may be variable. 
     In another further embodiment of the housing, the visually appealing display may include at least two lights, wherein the lights are adapted to radiate light of at least two different colors. In addition, the visual display may also include a light diffuser through which the at least two colors of light may pass. 
     In other further embodiments of the housing, the visually appealing display may include at least one light and a stand adapted to support the housing. Further, the stand may maintain the housing and the liquid source above a surface such that the fog may fall toward the surface after emanating from the liquid source. 
     In another further embodiment of the housing, the transducer may be adapted to vibrate between about 1.6 MHz and about 1.8 MHz. Further, the transducer may be adapted to vibrate at about 1.7 MHz. 
     In another further embodiment of the housing, the liquid may include a fragrance that is dispersed in the fog. 
     The invention also contemplates a method for delivering at least one pharmaceutical to at least one lung of a patient. This method includes: (a) providing a source comprising the at least one pharmaceutical, wherein each of the at least one pharmaceutical is in a substantially liquid form; (b) positioning a transducer in the source comprising the at least one pharmaceutical; (c) vibrating ultrasonically the at least one pharmaceutical with the transducer, to create a fog of the at least one pharmaceutical; (d) inhaling the fog formed of the at least one pharmaceutical, wherein the inhaling is done by the patient; and (e) delivering the fog to the at least one lung of the patient. 
     In a further embodiment of the method, the step of inhaling the fog may include: (d)(1) passing the fog through an outlet of a housing which contains the source comprising the transducer and the at least one pharmaceutical; and (d)(2) delivering the fog to the mouth of the patient through a conduit connected to the outlet. 
     In another further embodiment of the method, the method may further include: (f) monitoring a property of the at least one pharmaceutical with a sensor. 
     In another further embodiment of the method, the method may further include: (f) monitoring a property of the at least one pharmaceutical with a sensor; and (g) stopping the vibrating of the transducer if property of the at least one pharmaceutical, as measured by the sensor, is outside a predetermined range for the property. 
     In another further embodiment of the method, the step of vibrating ultrasonically the at least one pharmaceutical with the transducer may include: vibrating the transducer at between about 1.6 MHz and about 1.8 MHz, such as for example, at about 1.7 MHz. 
     The invention also contemplates a method for adding at least one fragrance to ambient air in a room. This method includes: (a) providing a source comprising the at least one fragrance, wherein each of the at least one fragrance is in a substantially liquid form; (b) positioning a transducer in the source comprising the at least one fragrance; (c) vibrating ultrasonically the at least one fragrance with the transducer, to create a fog of the at least one fragrance; and (d) emanating the fog formed of the at least one fragrance into the ambient air. 
     In a further embodiment of the method of adding fragrance to the ambient air in a room, the fragrance may be dissolved in a liquid solvent. 
     In another further embodiment of the method of adding fragrance to the ambient air in a room, the fragrance may be dissolved in a liquid solvent. Further, the method may also include: (e) monitoring a property of the at least one fragrance and the liquid solvent in the source with a sensor. 
     In another further embodiment of the method of adding fragrance to the ambient air in a room, the fragrance may be dissolved in a liquid solvent. Further, the method may also include: (e) monitoring a property of the at least one fragrance and the liquid solvent in the source with a sensor.; and (f) stopping the vibrating of the transducer if property of the at least one fragrance and the liquid solved in the source, as measured by the sensor, is outside a predetermined range for the property. 
     In another further embodiment of the method of adding fragrance to the ambient air in a room, the step of vibrating ultrasonically the at least one fragrance with the transducer may include: vibrating the transducer at between about 1.6 MHz and about 1.8 MHz, such as for example, at about 1.7 MHz. 
     The invention also contemplates a device for ultrasonically generating a fog of at least one liquid pharmaceutical. The device includes a transducer and a source containing the at least one liquid pharmaceutical. The transducer is adapted to vibrate ultrasonically and is positioned in the at least one liquid pharmaceutical. When the transducer vibrates ultrasonically, at least a portion of the at least one liquid pharmaceutical is changed into a fog which emanates from the device. 
     In a further embodiment of the device, the device may be adapted to be hand-held. 
     In another further embodiment of the device, the fog may emanate from the device through an outlet. 
     In another further embodiment of the device, the fog may emanate from the device through an outlet and into a conduit connected to the outlet. Further, the conduit may be adapted to transport the fog to a mouth of a patient. 
     In another further embodiment of the device, an air inlet may be provided in the device to prevent a vacuum from developing in the device if the pressure at the outlet is greatly reduced. 
     In another further embodiment of the device, the fog may emanate from the device through an outlet and into a conduit connected to the outlet. Further, the conduit may be adapted to transport the fog to a mouth of a patient and the conduit may be formed a material selected from the group consisting of rubber and plastic. 
     In another further embodiment of the device, the at least one pharmaceutical may be adapted to treat a condition of a lung. 
     In another further embodiment of the device, the at least one pharmaceutical may be adapted to treat asthma. 
     In another further embodiment of the device, the transducer may be adapted to vibrate at between about 1.6 MHz and about 1.8 MHz, such as, for example, at about 1.7 MHz. 
     These and other features, aspects, and advantages of the present invention will become more apparent from the following description, appended claims, and accompanying exemplary embodiments shown in the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention and together with the description, serve to explain the principles of the invention. 
     FIG. 1 is a perspective view of a housing for an ultrasonic fog generator, the housing having a plurality of lights thereon; 
     FIG. 2 is a cross-sectional view of the housing of FIG. 1 showing an ultrasonic transducer, a current control system interposed between a power source and the transducer, the cross-section being taken along line II—II in FIG. 1; 
     FIG. 3 is a perspective view of the housing of FIG. 1 in a container of liquid; 
     FIG. 4 is a cross-sectional view of a container of having a light diffuser in the form of faux ice therein, the ice covering a housing of the type shown in FIG. 1; 
     FIG. 5 is a side view of the housing and container of FIG. 3 supported by a stand, the figure showing fog emanating from the container falling toward a surface under the stand; 
     FIG. 6 is a cross-sectional view of the housing of FIG. 1, the cross-section being taken along live VI—VI in FIG. 1; 
     FIG. 7 is a circuit diagram representing theoretically the function of the current control system; and 
     FIG. 8 is a depiction of an alternate embodiment fog generator in which an ultrasound transducer and liquid are contained within a dispenser which has an outlet for directing fog to a patient through a conduit. 
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to presently preferred embodiments of the invention, which are illustrated in the drawings. An effort has been made to use the same reference numbers throughout the drawings to refer to the same or like parts. 
     FIG. 1 is a perspective view of a housing  10  for an ultrasonic fog generator. The housing  10 , which is preferably sized to be hand-held, has a plurality of lights  14 ,  16 ,  18 ,  20  thereon. Each of the lights  14 ,  16 ,  18 ,  20  is adapted to emit a particular color of light which may be the same as or different than the color emitted by one or more of the other lights  14 ,  16 ,  18 ,  20 . In addition, each of the lights  14 ,  16 ,  18 ,  20  may be adapted to change colors during use, i.e., the colors may be variable. Power for the lights  14 ,  16 ,  18 ,  20  is provided by a power source  30  and is delivered to the housing by a power cord  32 , as later described in detail. 
     Also shown on a top side  22  of the housing  10  is an indicator lamp  24 , an ultrasound depression  26  housing a transducer  40 , and a sensor  73  of a current control system  70  (later described in detail). The indicator lamp  24  contains a light source, such as a light emitted diode (“LED”), a halogen bulb, etc., which will continuously radiate light when the housing  10  is connected to a power source  30 . It should be readily apparent that the power source  30  may be any conventional power source such as a wall outlet proving AC current or a DC battery; the type of power source  30  employed will, however, determine whether an AC/DC converter is necessary. Regardless, power entering the housing  10  should be DC voltage, preferably at about 24 V. Accordingly, if an AC power source is used, a transformer would be necessary. 
     As previously mentioned, the ultrasound depression  26  houses a transducer  40  contained within the housing  10 . The transducer  40  may be a ceramic material which is adapted to vibrate at ultrasonic rates and which is electrically connected to the power source  30 ; the ceramic material can change electrical oscillations into mechanical oscillations (i.e., the ceramic material may vibrate at ultrasonic rates). It is within the ultrasound depression  26  that a conductive or at least semiconductive liquid  50  will be converted to a fog  60 , which may in the form of a mist, depending on the size of the droplets released into the air. The liquid  50  may be water, a pharmaceutical, a fragrance, a combination of any of these, or other liquid. Preferably, the housing  10  will be submerged between about 1.0″ and about 2.0″ and preferably at about 1.5″ in the liquid  50 . 
     The liquid  50  within the ultrasound depression  26  is oscillated by the transducer  40  within the housing  10  at between about 1.6 MHz and about 1.8 MHz and preferably at about 1.7 MHz. A variety of ultrasonic transducers manufactured by Nanhai Gentle Electronic Company, Ltd. (China) are capable of producing these oscillations; one preferable model is sold under product no. DH-24B. Another capable transducer is described in U.S. Pat. No. 6,361,024. One transducer  40  capable of producing such oscillations is shown in FIG. 2 which is a cross-sectional view of the housing of FIG. 1 taken along line II—II therein. As shown in FIG. 2, in addition to the ultrasonic transducer  40 , the housing  10  also contains a current control system  70  (later described in detail). 
     As shown in FIG. 2, power is delivered to the transducer  40  from the source  30  via a power cord  32  and through the current control system  70 . If the volume of the liquid  50  above the housing  10  (as measured by the current control system  70  and as later described in detail) is below a predefined limit, the current control system  70  may limit the amount of current from the power source  30  supplied to the transducer  40 . At a later time when the volume of the liquid  50  above the housing  10  is at or above the predefined limit, the current control system  70  can increase the current to the transducer  40  thereby enabling the transducer  40  to oscillate, preferably ultrasonically. 
     Absent a current control system  70 , if the housing  10  were insufficiently submersed, the transducer  40  may oscillate the liquid near the surface to such a degree that liquid, rather than fog, may be ejected from the container  100 . Further, all of the liquid  50  on top of the housing  10  could be ejected from the container  100 , thereby causing the housing  10  to operate without any liquid thereon and, therefore, wasting power and possibly damaging the device (e.g., overheating the ceramic transducer  40 ). Accordingly, to prevent this situation, a current control system  70  may be used to prevent power from reaching the transducer  40  when the housing  10  is insufficient submerged (or not submerged) in a liquid  50 . 
     The current control system  70 , which is described in detail in Chinese Patent Document No. ZL 96,236,955.1 and which is incorporated herein by reference, will now be explained in detail with respect to FIGS. 6 and 7. As shown in FIG. 6 (which is a cross-sectional view of the housing of FIG. 1 taken along live VI—VI thereof), there is provided a circuit board  72  which, in conjunction with the current control system  70 , controls whether power travels from the power source  30  to the transducer  40 . 
     Connected electrically to the circuit board  72  is a first conductor  78  (which may be a wire) which, in turn, is connected to a volume sensor  73 . The sensor  73 , which projects out of the housing  10 , includes an insulation wrapping  25  and contains a material  27  which has a variable resistance, the material  27  preferably being copper. For example, the resistance of the material could change in response to the temperature of the liquid  50  therearound, the temperature presumably being lower in a bottom portion of the container  100  holding the liquid  50  than in an upper portion thereof. For instance, a change in resistance based on a change is temperature is governed by the following equation: 
     
       
           R   T   =R   0 [1+α( T−T   0 )], 
       
     
     where R T  is the resistance at temperature “T”, R 0  is the resistance at a reference temperature “T 0 ”, and α is a coefficient of resistivity for a given material. By way of another example, the resistance of the material  27  could vary with the pressure applied thereto by the liquid  50 , the pressure being greater in a bottom portion of the container  100  than in an upper portion thereof. Such a change in resistance could be affected by a pressure sensitive resistor. However, the invention is not limited to any particular property which may alter the resistance of the material  27 . 
     As the sensor  73  is lowered in a liquid  50  (i.e., as the depth of submersion increases), the resistance of the material  27  correspondingly increases. As a result, as the depth of the sensor  73  increases, the voltage across the sensor  73  will increase, provided current remains substantially constant. In addition, the portion of the wrapper  25  on the exterior of the sensor  73  which passes through the upper side  22  of the housing  10  may be sealed with laminate plastic and/or rosin glue. 
     On an opposite end of the sensor  73  there is provided a second conductor  79 . When the housing  10  is immersed in a liquid  50  and the resistance of the material  27  increases, the voltage at the second conductor  79  increases. As the second conductor  79  is insulated by the wrapping  25 , the wrapping  25  acts as a dielectric between the second conductor  79  and the liquid  50 , i.e., the second conductor  79  and the liquid  50  form a capacitor. As the voltage experienced by the second conductor  79  increases, the capacitance between the second conductor  79  and the liquid  50  (represented by C X  in FIG. 7) will also increase. 
     As a result of the capacitance between the second conductor  79  and the liquid  50 , current will flow in the liquid  50  (i.e., the other “plate” of the capacitor) and will pass through the conductive outer casing  74  (e.g., which may be formed from a metallic material such as, for example, chrome or copper) and back into the circuit board  72  via a third conductor  75 , with a variable voltage. When the voltage at the third conductor reaches a predetermined level, a comparator (represented by U 2  in FIG. 7) will act to direct the current to the transducer  40  thereby enabling it to oscillate, preferably ultrasonically. 
     It should be noted that as the power through housing is DC current/voltage, there is no substantial risk of electrical shock from the current in the liquid  50 . In light of the aforementioned, the depth of the water affects the sensor  73  and the voltage thereacross such that it acts as a switch. It should also be noted that as the sensor  73  is insulated (by the insulation wrapping  25 ) from the liquid  50 , oxidation of the sensor  73  will be substantially inhibited. 
     FIG. 3 is a perspective view of the housing  10  of FIG. 1 in a container  100  of liquid  50 . As previously mentioned, the liquid  50  may be water, a pharmaceutical, a fragrance, a combination of any of these, or other liquid. Preferably, the liquid  50  is water. The housing  10  is placed in the container  100  such that it is submersed in the liquid  50  (other than the power cord  32  which may not be submersed). The housing  10  is submersed to a depth such that the transducer  40  will cause the liquid near the surface of the liquid  50  to oscillate. As the liquid  50  near the surface oscillates, it will evaporate in the form of a visual fog or mist. The density of the fog or mist will depend on the depth at which the housing  10  is submersed in the liquid  50 . 
     In conjunction with the container  100 , the housing  10  (and the lights  14 ,  16 ,  18 ,  20 ) can be incorporated into a visually appealing display. For example, as shown in FIG. 4 a light diffuser  110  (such as a pile of faux ice) may be added to the container  100  to cover the housing  10  substantially. The light diffuser  110  may be formed of plastic, quartz, a clear polymer, or other clear generally solid material which will not dissolved in the liquid  50 . Further, preferably, the light diffuser  110  will not chemically react or interact with the liquid  50 . In this embodiment, the light emitted by the lights  14 ,  16 ,  18 ,  20  will radiate through the light diffuser  110 , thereby illuminating the light diffuser  110 . 
     Regardless of whether a light diffuser  110  is provided, the container  100  may be supported by a stand  120  (as shown in FIG. 5) thereby maintaining the container  100  above a surface  122 . In this embodiment, when the fog is emitted by the liquid  50  in the container  100 , it may fall to the surface  122 , provided the fog is more dense than the ambient air surrounding the container  100 . 
     FIG. 8 is a depiction of an alternate embodiment fog generator  210  in a housing  10  (as previously described) and liquid  50  are contained within a dispenser  200 . The dispenser  200  has an outlet  202  for directing fog to a patient  204  through a conduit  206 , the conduit  206  preferably being formed of a flexible hose made of, for example, plastic or rubber. Essentially, this embodiment of the fog generator  210  works in the same manner as the previously described embodiments. However, the fog produced thereby is channeled through the outlet  202  and into a proximal end of the conduit  206 . To prevent condensation of the fog in the conduit  206 , the length of the conduit  206  is preferably less than about 6″. In addition, to prevent a vacuum from being creating in the dispenser  200 , an air inlet  203  may be provided. Further, to prevent fog from inadvertently leaving the dispenser  200  through the inlet  203 , an air filter  207  may be provided which substantially covers the inlet  203 . 
     If the patient  204  maintains a distal end of the conduit  206  in his mouth  205 , the fog may be inhaled into one or both of the patient&#39;s lungs. If the liquid  50  is a pharmaceutical, the fog thereof which is inhaled can be quickly transported to the blood of the patient via the capillaries in the lungs. In addition, if the patient suffers from asthma or other lung condition, the delivery to the lungs of the pharmaceutical in the form of the fog can provide quick treatment for such condition. 
     Although the aforementioned describes embodiments of the invention, the invention is not so restricted. It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed preferred embodiments of the present invention without departing from the scope or spirit of the invention. Accordingly, it should be understood that the apparatus and method described herein are illustrative only and are not limiting upon the scope of the invention, which is indicated by the following claims.