Abstract:
Methods and apparatus for dispensing the chemical solutions, such as a low viscosity liquid chemical solution for inhaling size, are disclosed. A small particle haze, including a liquid chemical, such as low viscosity liquids that are inhaled when in haze form, is created in an enclosed container. The small particle haze is created by one or more venturi nozzles. The small particle haze is filtered to remove particles in excess of a predetermined size. The remaining particles are combined with a stream of air that separates the particles into a dry haze. The stream of air also directs the combination into a dispensing tube that includes a plurality of outlets for dispensing the dry haze. Relatively small diameter sized dispensing tubes are formed of a relatively rigid material such as polyvinyl chloride (PVC). Larger sized dispensing tubes are inflatable. The air added to inflate inflatable tubes further separates the dry haze particles. Filtering prevents dirt and debris from polluting the dry haze that is created through the mixture of clean dry air with the small particles.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims the benefit of U.S. Provisional Application No. 60/755,544, filed Dec. 30, 2005, the subject matter of which is incorporated herein by reference. 
     
    
     BACKGROUND  
       [0002]     In the past, spraying machines have been used to dispense chemical solutions, such as solutions containing nasal inhalers or breathing medications. More recently, haze machines for dispensing bird repellent liquid chemical solutions, such as liquid drug solutions (for example, methyl anthranilate (MA) solutions), have been developed. For this application, haze refers to the air that is breathed containing a mixture of small particles floating throughout a large area. Droplets included in the haze were formed by a process utilizing air pressure over a single droplet of fluid, then filtering the small particles to obtain the smallest particle. Once these tiny particles are released, separation by air became critical to keeping the particles separated throughout the area required for distribution.  
         [0003]     The use of fogging machines and other mechanisms for dispensing solutions or chemicals in other forms has a number of disadvantages, some of which are described in detail in U.S. patent application Ser. No. 10/646,089, titled “Hazing a Bird Repellent Solution,” and earlier filed Provisional Application No. 60/405,663, both of which are incorporated herein by reference. Among other disadvantages is the size of the liquid droplets included in the fog produced by fogging machines and some misting and spraying machines. Unfortunately, the majority of droplets created by fogging machines are larger than desirable. That is, the majority of the chemical droplets produced by fogging machines are greater than 20 microns in size. As a result, the chemical droplet fog created by fogging machines is somewhat wet, resulting in the creation of a residue on surfaces that come in contact with the fog. Another disadvantage is the heating of the liquid in order to vaporize the solution. Fogging machines have other disadvantages that are described in detail in U.S. patent application Ser. No. 10/646,089 and Provisional Application No. 60/405,663. In order to overcome these disadvantages, haze machines for dispensing chemical solutions, such as nasal or oral inhalers for solutions of medical value, have been developed. Such machines are described in the foregoing patent application and provisional application. The haze machines described in the foregoing provisional application include venturi nozzles that employ a Bernoulli effect to create a dry haze of small size particles. More specifically, pressure air (over 25 psi) applied to the venturi nozzles of such haze machines causes the nozzles to draw small droplets of solution from a reservoir and break the droplets into small size particles. The majority of the particles are of a size sufficiently small (20 microns or less) to deeply penetrate the airway passages. Filtering the particles removes larger than desired particles to maintain smaller particles that stay airborne for long periods.  
         [0004]     Maintaining liquid drug particle size is important to the successful use of creating a dry haze in the air that stays dry, keeps the particles small, and spreads out over a large area. Smaller size particles penetrate deeper into the airway passages than do larger size particles. As a result, smaller size chemical solution particles are more effective to inhale deeply than larger size particles. The literature for flying birds shows that chemical particles less than 20 microns in size are the most desirable. Maintaining the small size of chemical particles is difficult with most methods of distribution. Liquids, drugs and chemical particles have a tendency to coagulate (i.e., combine) if several small particles are either released together at the same location, or pushed into a small area and/or around sharp comer. Coagulation is caused by the lack of sufficient space between the particles. Coagulation causes small particles below 20 microns to become larger droplets outside of the haze machine generating the smaller particles initially. More specifically, when the small particles touch, they enlarge and form droplets that are wet. The wet droplets drip and form wet areas (i.e., residue) on the surfaces that the droplets contact, wasting material. Maintaining a separation between small particles causes a drying effect on the haze. One way of maintaining a separation between liquid chemical particles suggested in the foregoing patent application and provisional application, in addition to normal wind movement, is the use of a fan positioned outside of a haze machine.  
         [0005]     In summary, it has been known for several years that small size particles smaller than 20 microns, are more effective as an inhaled substance than large size particles, i.e., particles above 20 microns. Recent testing has shown that the continuous separation of particles is important to keeping the size of particles below 20 microns.  
         [0006]     While haze machines of the type generally described above and in more detail in U.S. patent application Ser. No. 10/646,089, and Provisional Patent Application No. 60/405,633, have been a significant advance in the dispensing of liquid chemicals, such machines and the methods they employ are subject to improvement. The present invention is directed to such improvements particularly with respect to keeping the size of liquid drug chemical particles small.  
       SUMMARY  
       [0007]     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.  
         [0008]     Methods and related apparatus for dispensing chemical solutions, for inhalation size are disclosed. A haze is described here as small particles from a liquid that are floating in the air for long periods of time. A haze that includes a liquid chemical is created in an enclosed container. The enclosed container includes a reservoir of the chemical solution. Preferably, the haze is created using one or more venturi nozzles. The venturi nozzles draw the chemical solution, preferably through a filter, from the reservoir and break the chemical solution into particles of a size suitable for inhalation. The resulting small particle haze is filtered, preferably by a layered series of filters, to remove particles in excess of a predetermined size. The separation between the remaining particles is increased by a blower adding air to the filtered particle haze. The added air, in effect, decreases the number of particles per cubic unit of the resulting particle/air combination. The result is a dry haze that is substantially invisible. The dry haze is injected by the blower into a distribution system. Preferably, the distribution system includes one or more dispensing tubes that include a plurality of outlets located along the length of the dispensing tubes for dispensing the dry haze. Relatively small diameter dispensing tubes may be formed of a rigid material, such as polyvinyl chloride (PVC), galvanized metal, stainless steel or other material that is not reactive to the chemical. Large diameter dispensing tubes may be inflatable, rigid, or collapsible. Inflatable dispensing tubes are preferably inflated by a fan positioned at one end of the tube, upstream of where the liquid droplet haze enters the tubes. While a fan is the most cost effective method, other inflation methods can also be used. Introducing the fan air upstream from the haze, increases the separation between the droplets that form the haze, thereby maintaining the small size droplets throughout the system and increasing the amount of dry haze being distributed. More specifically, the air added by the fan, in effect, further decreases the number of particles per cubic unit of the resulting particle/air combination causing particles to stay separated, not touch or re-coagulate into larger size particles.  
         [0009]     In accordance with other aspects of this invention, preferably, the enclosed container is located in a housing that also includes a compressor that generates pressurized air for the venturi nozzles. Filtering prevents the compressor from deteriorating as a result of exposure to, or ingestion of, the chemical solution that may or may not react to internal parts of the mechanism.  
         [0010]     In accordance with further aspects of this invention, preferably the blower is also located in the housing. Preferably, the blower comprises a vacuum blower and a truncated cone nozzle connected to the output of the vacuum blower.  
         [0011]     As will be readily appreciated from the foregoing summary, the separation between haze particles is increased in various ways as the haze is distributed. The increase in separation is created by adding air to the haze and directing the haze into a suitably large distribution system. Increasing the separation distance between the haze particles prevents the particles from coagulating and becoming large. The end result is the emission of a dry haze that is substantially invisible under normal lighting conditions. 
     
    
     DESCRIPTION OF THE DRAWINGS  
       [0012]     The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:  
         [0013]      FIG. 1  is a pictorial diagram of an exemplary liquid chemical haze generator coupled to a relatively small diameter dispensing tube;  
         [0014]      FIG. 2  is a pictorial top plan view of a liquid chemical haze generator coupled to a relatively large diameter dispensing tube;  
         [0015]      FIG. 3  is a side elevation view of the relatively large diameter dispensing tube shown in  FIG. 2 , vertically suspended;  
         [0016]      FIG. 4  is an exploded view of the haze generator illustrated in  FIGS. 1 and 2 ;  
         [0017]      FIG. 5  is an elevational, cross-sectional view of the haze generator illustrated in  FIGS. 1, 2 , and  4 ;  
         [0018]      FIG. 6  is a pictorial view of the haze generator illustrated in  FIGS. 1, 2 ,  4 , and  5  from a different angle;  
         [0019]      FIG. 7  is a further exploded view of the haze generator illustrated in  FIGS. 1, 2 , and  4 - 6 ; and  
         [0020]      FIG. 8  is an electrical schematic diagram of the haze generator illustrated in  FIGS. 1, 2 , and  4 - 7 . 
     
    
     DETAILED DESCRIPTION  
       [0021]     The literature has established that liquid chemical solutions in varying forms can function as airborne particles less than 20 microns in size (preferably less than 10 microns), greatly improving the use of liquid chemical solution that can be distributed for inhaling over large areas. It is believed that the airborne reduced size particles penetrate deeper into the nasal or oral airway passages when inhaled, thereby causing a reasonable enough reaction, i.e., as an inhaler for use in receiving chemical, that it can be dispensed over large areas for many to inhale and obtain sufficient effect over a period of time. In effect, the haze reduces the need for individual attention and increases the ability to spread liquid chemicals more safely and efficiently than past use of sprayers that are wasteful and messy.  
         [0022]     While previously developed chemical haze machines have been a significant advance in the use of creating efficient dry airborne haze, previously developed haze machines are subject to improvement. In this regard, previously developed haze machines generally comprise two separated units: a compressor and a haze generator. The compressor and the haze generator may be coupled together by a high pressure line that directs compressed air produced by the compressor to the haze generator. As more fully described in U.S. patent application Ser. No. 10/646,089 and Provisional Patent Application No. 60/405,633, more fully referenced above and incorporated herein by reference, previously developed haze generators include a tank that is formed of material that is nonreactive to liquid chemical solutions. That tank includes a reservoir and one or more pickup tubes for withdrawing fluid from the reservoir, which contains the solution. The pickup tubes, with filters for removing dirt or particles to large to be used, connect the reservoir to one or more venturi nozzles. The venturi nozzles include a high (above 25 psi) pressure input connected to the pressure line from the compressor and a fluid input connected to a pickup tube. The venturi nozzles are designed such that as pressurized air is emitted via an outlet, also called a jet, liquid drug solution is withdrawn from the reservoir. More specifically, the pressurized air, in accordance with the Bernoulli effect, creates a low pressure region that pulls or withdraws very small amounts of an MA solution from the reservoir via a pickup tube through a filter. In addition to withdrawing MA fluid, the small orifice directs very small amounts, i.e., droplets, of chemical fluid into the pressurized air pathway, vaporizing the fluid into small particles that form a haze-like mist, small enough to float and stay airborne when released to the atmosphere. Prior to exiting the haze generator, large droplets in the mist either strike the inside walls of the reservoir and drain back into the bottom of the reservoir or are removed by a filter and returned to the reservoir.  
         [0023]     While haze machines of the type generally described above and described in more detail in the foregoing patent and provisional applications have been a substantial improvement in mechanisms for dispensing the solutions, such haze machines are subject to improvement. For example, in such haze machines, the compressor and the haze generator may be separated by a substantial distance. Separation was thought to be necessary to prevent any residue created by the haze produced by the haze generator from having a deleterious effect on the equipment. In this regard, drug solutions in their liquid state may be relatively caustic to certain working parts of the mechanism. If the particles that form a haze are not separated by large volumes of air, i.e., do not form a dry haze, the particles tend to coagulate into large droplets that form a residue on any surface that the droplets contact. The presence of a residue decreases the life of equipment located in close proximity of a haze as compared to the life of similar equipment located in an area not containing haze. In addition, while the foregoing patent and provisional applications suggest the use of a fan to disperse the haze generated by a haze generator after the haze leaves the generator, fans do not have a precise directional effect, making it difficult to direct the haze to specific locations in a building or other structure where distribution is desired.  
         [0024]     As will be readily appreciated from the foregoing description, in order to make a dry haze it is necessary to at least maintain, and preferably increase, the separation between the small liquid chemical particles that form the haze. Increasing the separation between the small particles that form the haze stops the particles from touching each other and coagulating. As described more fully below, in accordance with the invention, a dry haze is maintained by adding air to a haze formed of small particles. The added air increases the separation between the particles, thereby reducing the possibility of coagulation of the individual particles into wet droplets that can form a residue. This result is accomplished by using a blower and, in some embodiments, a fan to increase the volume of air and the movement of air upstream of the haze introduction point.  
         [0025]     While the various embodiments of the invention described herein were developed for use with chemical solutions and are described in combination with an MA solution as the bird repellant, it is to be understood that embodiments of the invention may work equally well with other chemical solutions, as well as with other products suitable for dispensing in a haze or mist form.  
         [0026]      FIG. 1  illustrates a haze generator  11  formed in accordance with the invention connected to an elongate, relatively small diameter dispensing tube  14  formed of a suitably rigid material that is nonreactive to the chosen chemical haze, such as polyvinyl chloride (PVC). The dispensing tube  14  is connected to the outlet  15  of the haze generator  11  via coupling  13  and a short tube  12  sized to match the outlet  15 —2 inches in diameter, for example. The dispensing tube  14  includes a plurality of holes  16  located along the length of the tube  14 . The end of the dispensing tube  14  is closed by an end cap  18 . As more fully described below, preferably, the diameter of the tube  14  falls in the 3 inch to 4 inch range and has a length of less than 200 feet. The plurality of holes  16 , which are preferably about ½ inch in diameter, are spaced apart by a suitable distance, such as 10 feet, for example.  
         [0027]     While relatively small diameter (e.g., 3- to 4-inch) rigid dispensing tubes  14 , formed of PVC or some other suitable material, are suitable for use as a distribution system in some environments, particularly those having relatively short-run distance requirements, in other environments, particularly those having relatively long-run distance requirements, larger dispensing tubes are more desirable to in order to help keep small haze particles separated and as small as initially generated to thereby maintain a dry haze that continually floats in the air and mixes in the atmosphere.  FIGS. 2 and 3  illustrate such dispensing tubes. More specifically,  FIGS. 2 and 3  illustrate a haze generator  11  similar to the haze generator illustrated in  FIG. 1  connected by the short outlet tube  12  to a large inflatable tube  19 . Located at one end of the large inflatable tube  19  is a fan  21  with a filter  22  located on the intake side of the fan for removing contaminants. The filter may be formed of PVC filter foam, for example. The short tube  12  enters the large inflatable tube  19  downstream from the fan  21 . When energized, the fan  21  inflates the large inflatable tube  19  and assists in separating the haze particles created by the haze generator  11  and moving the particles down the inflatable tube  19 . As shown, the end of the large inflatable tube is closed by an end cap  22 . While various sized fans can be used, in one actual embodiment of the invention, the fan produces approximately  25  mph wind and pressurizes a large inflatable tube to sufficiently inflate the entire tubing the full length and have sufficient air flow velocity to dispense the haze at least 10-60′.  
         [0028]     As best illustrated in  FIG. 3 , preferably the large inflatable tube  19  is hung from a suitable support cable  23  by loops  25  located along the length of the tube  19 . The loops make take on many forms, such as wire ties, ropes, belts, etc. If desired, the support cable may include one or more turnbuckles for tightening the cables.  
         [0029]     Located along the length of the large inflatable tube  19  are a plurality of U-shaped flaps  27  spaced apart by a distance of 10 feet or so. Preferably, the U-shaped flaps are roughly 2 inches by 2 inches in size. When the fan  21  is energized, the pressure created by the fan in the large inflatable tube  19  is sufficient to cause the inflatable tube to become semi-rigid and the U-shaped flaps to open. As a result, MA haze or mist produced by the haze generator  11  entering the large inflatable tube  19  is emitted from the U-shaped flaps when the fan  21  is energized. As noted above, a filter  22 , made from a material that is non-reactive to desired chemical, is added to the intake of the fan to prevent dirt and debris from entering the system.  
         [0030]     The diameter of the inflatable tube  19  may vary from 10 to 18 inches, for example. Obviously, the fan  21  is either sized to have the same diameter as the large inflatable tube  19 , or reducers or expanders are used to adapt the output of the fan to the large inflatable tube  19 . Preferably, the fan and the large inflatable tube are formed of materials that are non-reactive material to the desired chemical, such as rip-stop nylon coated with polyurethane. In particular, preferably the blades of the fan are formed of material that is non-reactive to the desired chemical solutions, such as nylon, aluminum, or powder coated sheet metal, for example.  
         [0031]     As will be readily appreciated from viewing  FIG. 3 , large inflatable tubes of the type illustrated in  FIGS. 2 and 3  are ideally suited for suspension from the rafters of barns or other structures and, thus, are reasonably positionable to emit dry haze in the regions of such structures where open air flow is least likely to be disrupted. As noted above, the separation of the particles that form a haze is important to maintaining the dryness of the haze. The air added by the fan  21  helps keep the haze dry by keeping the particles separated throughout the entire distribution system. The initial dry haze mixes with the added air, creating a larger volume of dry haze, thereby increasing the size of distribution area. Ideally, the haze emitted via the holes  16  ( FIG. 1 ) or the U-shaped flaps  27  ( FIG. 3 ) is substantially invisible in normal lighting conditions.  
         [0032]     It has been found that large diameter inflatable tubes are more ideally suited for longer runs than smaller diameter rigid tubes, especially when a change in direction is desired. By way of example only, inflatable tubes having a diameter of 12-18 inches are ideally suited for runs in the 200-900 foot range, inflatable tubes having a diameter of 10 inches are ideally suited for runs in the 150-400 foot range, rigid tubes having a diameter of 4 inches are ideally suited for runs in the 100-150 foot range, and rigid tubes having a diameter of 3 inches are ideally suited for runs less than 100 feet. The increase in tube diameter allows the particles that form the liquid chemical haze to remain separated from each other for longer distances. The distance is directly related to the volume of the distribution system. As with the design of most air moving systems, tapering the size of the tubing is not necessary; however, tapering can be used if desired. Regardless of how structured the pressure of the air created by the fan should be sufficient to inflate the tubing and cause enough air movement throughout the tubing such that, when the dry haze exits through the U-shaped flaps  27 , the exiting velocity is sufficient for the dry haze to travel long distances and cover large areas. As noted above, in one actual embodiment of the invention, the fan generates approximately 25 mph wind and the inflatable tube is inflated sufficiently to have air flow leaving the tubing to travel at least 10-60′. The haze exiting this embodiment has a velocity in the 8-9 mph range. There is about 3 foot pounds of back pressure buildup on the blades of the fan.  
         [0033]      FIGS. 4-7  illustrate the haze machine  11 . The haze machine  11  includes a two-piece housing comprising a base  31  and a cover  33 . Both the base  31  and the cover  33  are formed of a suitable material that is nonreactive to the desired chemical, such as sheet metal coated with powder. Both the base  31  and the cover  33  have a right angle U-shape. More specifically, the base  31  includes a bottom  35  and front and rear walls  37  and  39 . The cover  33  includes a top  41  and side walls  43  and  45 . The bottom  35  and front and rear walls  37  and  39  include inwardly extending flanges to which the adjacent edges of the side walls  43  and  45  are attached via, for example, sheet metal screws. When the base  31  and cover are joined, the housing has the overall shape of a right rectangular parallelepiped. The side walls  43  and  45  of the housing include a plurality of louvers  49  covered on the inside with a layer of filter material  51  that removes contaminants from air entering the housing.  
         [0034]     Mounted in the housing so as to lie parallel to the base  35  is a shelf  53 . Located beneath the shelf  53  is a haze generator  55  and a compressor  57 . The compressor  57  is attached, by bolts, for example, to the bottom  35  of the base  31  of the housing.  
         [0035]     The haze generator  55  includes a chamber  58 , the lower portion of which forms a reservoir for a solution  59 . The chamber  58  has the shape of a right rectangular parallelepiped. Like the base and cover, the top, bottom, and side walls of the chamber are formed of a suitable material that is nonreactive to the desired chemical—sheet metal coated with powder, for example. Located inside of the chamber  58 , above the solution  59 , is a venturi head  61 . The venturi head includes one or more venturi nozzles, three in the exemplary head  61  shown in  FIG. 5 . The venturi head  61  is connected to a tube  63  connected to the output port of the compressor  57 . The inlet port of the compressor is connected to a filter  65  via an inlet tube  67 .  
         [0036]     Returning to the venturi head  61 , in addition to receiving pressurized air from the compressor  57 , a plurality of pickup tubes  69  equal in number to the number of venturi nozzles in the venturi head, i.e., three in the illustrated exemplary head, extend into the solution  59 . Preferably, the ends of the pickup tubes  69  that extend into the solution each include a filter  71 . As described in more detail in the patent and provisional applications referenced above, the pressurized air produced by the compressor  57  creates a Bernoulli effect in the venturi nozzles of the venturi head  61 . The Bernoulli effect causes very small amounts (i.e., droplets) of fluid to be withdrawn from the solution  59  and broken into a mist or haze  72  formed by particles. The mist or haze  72  is emitted from the venturi nozzles of the venturi head  61 . While various pressures can be used, preferably the compressor pressure is in the 22-30 pounds per square inch (psi) range, preferably 29 psi.  
         [0037]     As shown by an arrow  109 , the mist or haze  72  exits the chamber  58  via a short tube  73  mounted in the top of the chamber  58 . Preferably, the short tube  73  includes a plurality of filter layers  75   a,    75   b,    75   c  . . . , each decreasing in size from the bottom of the short tube nearest the interior of the chamber  57  to the top of the short tube  73 , as represented by the decreasingly sized holes in the filter layers  75   a,    75   b,    75   c  . . . shown in  FIG. 5 . Preferably, the filter layers  75   a,    75   b,    75   c,  . . . are formed of material that is non-reactive to the desired solution, such as PVC filter foam.  
         [0038]     Extending into the top of the short vertical tube  73  is an angled leg  77  of a generally Y-shaped coupling  79 . A space  81  for drawing air into the angled leg  77  is located between the angled leg  77  and the top of the short tube  73 . The intake air is represented by an arrow  83  in  FIG. 5 . The intake air  83  is mixed with the particles, represented by an arrow  111 , that have passed through the filter layers  75   a,    75   b,    75   c  . . . Preferably, the generally Y-shaped coupling is formed of a rigid material, such as PVC.  
         [0039]     Mounted atop the shelf  53  is a blower  85 . The blower  85  is a vacuum-type blower. More specifically, the blower  85  has an enlarged opening on one side for receiving air represented by an arrow  87 . The blower  85  pressurizes the air and emits a stream of air  90  via a truncated cone nozzle  89  positioned over the outlet of the blower  85 . The truncated cone nozzle  89  extends into a second leg  91  of the generally Y-shaped coupling  79 . Like the generally Y-shaped coupling, the truncated cone nozzle is formed of a suitably rigid material, such as PVC. While various types of vacuum and other blowers can be used, in one actual embodiment employing a vacuum blower, the velocity of the stream of air exiting the truncated cone nozzle was about 90 mph. Obviously, this speed should be construed as exemplary, not limiting, since various speeds can be used. The speed and air volume emitted from the truncated cone nozzle must be sufficient to inject the haze into the distribution system, which requires overcoming any back pressure in the distribution system caused, for example, by the fan  21  illustrated in  FIGS. 2 and 3  and described above.  
         [0040]     The third leg  93  of the generally Y-shaped coupling is connected to an output coupling  95  that forms the outlet  15  of the haze generator  15 . The air stream produced by the blower  85  that exits the truncated cone nozzle creates a venturi that, in effect, draws the newly created haze or mist produced by the chemical vaporization process through the filter layers  75   a,    75   b,    75   c,  and mixes the haze with additional air, filtered from inside of the body of the haze generator  55 , to help separate the haze particles and keep them apart for a longer period of time. The filter layers  75   a,    75   b,    75   c  . . . remove large haze particles and excess spray particles from the haze or mist. Excess spray particles are particles that impinge on the surfaces of the interior walls of the chamber  58 . The removed large and excess spray particles drop or slide down the side walls of the chamber  58 , back into the solution  59 . As a result, only relatively small particles are emitted from the outlet  15 . The filtering is such that the majority of the small particles are less than 20 microns in size, preferably below 10 microns. The generally Y-shaped coupling is held in place by a U-shaped bracket  97 , which may be formed of sheet metal. The output coupling  95 , like the short tube  73 , the generally Y-shaped tube  79 , and the truncated cone nozzle  89 , is formed of a rigid material that is nonreactive to the desired chemical solution, such as polyvinyl chloride (PVC), for example.  
         [0041]     Extending upwardly from the top of the chamber  58  is a long tube  99  that is enclosed at its upper end by a cap  101 . Located between the cap  101  and the inner side of the upper part of the long tube  99  is a filter  103 . The filter  103  allows air to be drawn into the long tube  99 , as shown by the arrows  105 . Air entering the tube exits the lower end of the tube, as shown by arrow  107 , and enters the chamber  58 . The long tube  99  is used to add the desired chemical solution to the chamber  58 . Preferably, a dipstick  109 , which is accessible when the cap  101  is removed, is used to check the level of the solution  59  in the chamber  58 .  
         [0042]     In summary, when the compressor  57  and the blower  85  are energized, pressure produced by the compressor  57  causes the venturi head  61  to create an mist or haze in the region of the chamber  58  above the solution  59 . The mist or haze exits the chamber  58  via the filters in the short tube  73 , as shown by the arrows  109  and  111 . Exiting is assisted by the air stream  90  created by the blower  85  via the truncated cone nozzle  89 . The resultant fine mist or haze, which includes a majority of particles less than 20 microns in size, exits the haze generator  11  via the outlet coupling  95 . The air added to the dry haze exiting the chamber  58  via the filters in the short tube increases the distance between the particles that form the haze to thereby prevent the coagulation, i.e., combining of the particles. The high-speed air stream emitted by the truncated cone nozzle injects the resulting dry haze into the distribution system. Distribution systems that include a fan, such as the distribution system illustrated in  FIGS. 2 and 3  and described above, adds additional air to the haze thereby separating the particles further. The end result is an almost invisible haze exiting the distribution system. While it is possible that dry haze particles leaving the filter layers in the short tube  73  might coagulate, particularly after the haze machine is de-energized, droplets resulting from such coagulation drain back through the filter layers into the chamber  58  and become part of the liquid solution located in the bottom  59 .  
         [0043]     The haze generator  11  illustrated in  FIGS. 4-7  includes a number of features, some or all of which may be included in actual embodiments of the invention. Among these features are the use of filters positioned to prevent mist or haze from impacting the operation of the compressor  57  and the blower  85 . Notable in this regard are the filters  51  located inside of the louvers  49  of the housing. Filter  65  insures that air entering the compressor is clean. The filter  103  at the top of the long tube  99  insures that air entering the housing via the long tube is also clean of dirt or debris, as well as other contaminants. The venturi effect of the air stream created by the truncated cone nozzle  89  insures that air  85  is drawn into the angled mist or haze leg  77  of the generally Y-shaped coupling rather than the haze or mist entering the housing. The filter foam  51  is located along the inside walls of the cover  33  adjacent to the inside of the louvered vents  49  filter dirt, debris and other contaminates from air entering the housing.  
         [0044]      FIG. 8  is a control circuit for controlling the operation of the haze generator  11 . AC power hot and neutral lines  121  and  123  are connected to the haze generator via a double-pole, double-throw On/Off switch  125 . Preferably, one of the AC power lines, such as the hot power line  121 , is protected by a fuse, circuit breaker or other protective device  127 . The hot output of the On/Off switch  125  is connected to one of the power terminals of a relay  129  and to one of the power terminals of a printed circuit board (PCB)  131 . In the illustrated exemplary embodiment, the PCB includes a stepdown transformer  132 , an AC to DC converter  134  and a timer  136  and the power terminals are connected to the input terminals of the step down transformer. The neutral output of the On/Off switch  125  is connected to the other power terminal of the other input of the step down transformer  132 , the neutral terminal of the compressor  57 , and to one terminal of a single-pole, double-throw two-speed switch  133 . One of the poles of the two-speed switch is directly connected to the neutral or hot terminal of the blower  85 , and the other terminal is connected to the neutral or hot terminal of the blower  85  via a rectifier diode  135 . The opposite terminals of the blower and the compressor are connected to the other power terminal of the relay  129 .  
         [0045]     The output of the step down transformer  132  is connected to the input of the AC to DC converter  134 , which connects the AC input to a DC output. The DC output of the AC to DC converter is connected to the power input of the timer  136 . Preferably, the on/off time cycle of the time is adjustable, preferably remotely adjustable (not shown). The coil terminals of the relay  129  are connected to the output of the printed circuit board/timer  136 .  FIG. 8  also illustrates the starting capacitor  137  of the compressor  59 .  
         [0046]     In operation, when the On/Off switch  125  is closed and the timer  136  is set to apply power to the relay  129 , the relay closes, resulting in power being applied to the blower and the compressor. Either full power or half power is applied to the blower  85 , depending on the position of the two-speed switch. Half power is applied when the two-speed switch is positioned to apply power via the rectifier  135  because the rectifier reduces the RMS value of the AC input voltage by one-half. The timer is an On/Off timer that causes the haze generator to be energized in intermittent fashion, depending upon the environment of use. As noted above, preferably, a remote control unit connectable to a connector on the printed circuit board  131  is used to remotely adjust the cycle time of this On/Off timer.  
         [0047]     While a preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein within the scope of the invention as defined by the appended claims. For example, rather than the straight small and large diameter dispensing tubes illustrated in  FIGS. 1-3 , the dispensing tubes can include elbows and branches, if desired.  
         [0048]     While illustrative embodiments have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.