CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This Application claims priority from Provisional U.S. Application No. 60/744,988, filed on Apr. 17, 2006. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to a gravity flow fountain and, more particularly to a method of, and apparatus for, actuating and controlling the valve operation of a gravity flow fountain.  
         [0003]     Gravity flow fountains of various designs and configurations can generate a display comprising a cascade of water droplets. These water droplets, when grouped together and properly synchronized, assume or compose various shapes, images, and/or messages. The shape and resolution of the images is controlled by selectively opening and closing numerous small holes in a bottom of a fluid filled manifold. The holes are opened and closed by the retraction and insertion, respectively, of needle-shaped plugs into the hole. The movement of the needle plugs is driven by solenoids. Typically, for ease of construction, multiple needle plugs will be controlled as an array.  
       BRIEF SUMMARY OF THE INVENTION  
       [0004]     In one embodiment, the invention is a free falling water droplet fountain comprising a manifold having a series of openings, at least one control assembly for independently controlling the size and rate of release of water droplets from the openings, the controlling assembly including a plurality of pneumatically actuated valve assemblies for defining the form and size of the water droplets.  
         [0005]     In another embodiment, the invention is a system for controlling droplet formation in a fountain, the system comprising: at least one pneumatic solenoid valve in fluid communication with a source of pressurized air; at least one manifold having a series of openings; at least one control assembly for independently controlling the size and rate of release of water droplets from the openings, the controlling assembly including a plurality of pneumatically actuated valve assemblies for defining the form and size of the water droplets, wherein the valve assemblies are controlled between an open position and a closed position by selective actuation of the pneumatic solenoid. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIG. 1  is a schematic view of the pneumatically activated fountain.  
         [0007]      FIG. 2  is a side cross-sectional view of the valve piston assembly.  
         [0008]      FIG. 2A  is a side view of electric-solenoid valve assembly.  
         [0009]      FIG. 3  is a schematic view of the fountain waterfall.  
         [0010]      FIGS. 4A and 4B  are schematic top oblique and side cross-sectional views of the waterfall module.  
         [0011]      FIGS. 5A and 5B  are schematic top oblique and side views of a sound enclosure.  
         [0012]     FIGS.  6 A-D show schematic views of modular sound enclosures.  
         [0013]      FIG. 7  shows a schematic view of a sound curtain.  
         [0014]      FIG. 8  shows a schematic view of an embodiment where the module is submerged under water. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0015]     In general, gravity flow fountains capable of generating these displays are known in the art. By way of example, U.S. Pat. No. 4,294,406 to Pevnick discloses a program controllable free falling water drop fountain and U.S. Pat. No. 6,196,471 to Ruthenberg discloses an apparatus for providing a waterfall or fountain capable of making displays formed from water droplets. Further, U.S. Pat. No. 6,053,423 to Jacobsen, U.S. Pat. No. 5,524,822 to Simmons, and U.S. Pat. No. RE35,866 to Simmons teach methods of producing fountain images and displays using nozzles or timely released, gravity-affected droplets. Additionally, U.S. Pat. No. 5,737,860 to Whigham discloses a method and apparatus employing gravity to display a message. Also, U.S. Pat. No. 6,557,777 to Pevnick discloses a water supply method and apparatus for a gravity fountain. All of these U.S. patents are incorporated herein by reference.  
         [0016]      FIG. 1  shows a schematic view of the pneumatically activated fountain of this invention. The air drive system  1  comprises an air compressor  3 , which is connected to an electrical source  5 . Air compressor  3  provides a source of compressed air, typically at a pressure between about 125 to about 150 psi. The compressed air travels through a conduit  7  to a first pressure regulator/oiler  9 .  
         [0017]     Pressure regulator/oiler  9  comprises an air filter  11 , a regulator valve  13 , a pressure gauge  15 , and an oiler  17 . First pressure regulator/oiler  9  functions to both reduce the pressure and to reduce fluctuations in the air pressure. Typically, the air pressure can be between about 100 to about 150 psi exiting the first regulator/oiler  9 .  
         [0018]     A main accumulator  19  is provided after the first pressure regulator/oiler  9  to provide a buffer for compressed air. This buffer acts to help smooth out pressure fluctuations from the compressor. Compressed air from the accumulator passes through conduit  21  to a second pressure regulator/oiler  23 .  
         [0019]     The second regulator/oiler  23  comprises an oiler  25 , a pressure gauge  27 , a pressure regulator valve  29 , and a filter  31 . The second pressure regulator/oiler  23  further reduces the pressure, in this example to about 75 psi.  
         [0020]     The compressed air from the second pressure regulator/oiler  23  is split out to each individual control module by the first flow divider  35 . In this view, only one module is shown, but other modules may be added as desired. Compressed air from the first flow divider  35  passes through conduit  33  to an air branch manifold  37 .  
         [0021]     Air branch manifold  37  has a number of taps  39 . Compressed air flows from a tap  39  through a conduit  41  to a second flow divider  43 . Flow divider  43  splits the flow between conduits  45   a  and  45   b  which each feed opposite ends of branch accumulator  47 . Although not shown in detail here, each of the other taps  39  of air branch  37  will feed a separate branch accumulator  47 . Feeding both ends of accumulator  47  prevents dead spots of low pressure within the accumulator and has been found to be able to provide each of taps  49  with essentially the same air pressure (pressure differentials of 0.25 psi or less).  
         [0022]     Compressed air from the branch accumulator  47  flows through a conduit  51  attached to an accumulator tap  49  to a pressure regulator  53 . Again, although not shown, each tap  49  will provide air to a separate line  51  feeding a separate pressure regulator  53 . Pressure regulator  53  is preset and, therefore, does not require a gauge, although a gauge may be placed at this position if desired. The regulated air from pressure regulator  53  passes through conduit  55  to a pneumatic solenoid valve  57 .  
         [0023]     Pneumatic solenoid valve  57  drives piston  61  via conduit  59 . The operation of solenoid valve  57  is driven by computer controller  63 . Computer controller  63  operates a program stored on either memory  65  or obtained through the ethernet  67 . The program is designed to control the timing and movement of the pistons  61  so as to make desired graphical image. Output from the computer controller  63  is sent to each solenoid valve  57  via a solid state switch array  73 .  
         [0024]     One embodiment of the air piston has a spring return. The spring is inside the air cavity or part of the current mechanical commercially available air piston. There is an electronically controlled air valve that governs the air piston. In another embodiment, the electronically controlled air valve  57  can switch the direction of the air flow so that the air piston  61  closed with air pressure as well as opens with air pressure. The speed of air closing might also be on a second regulator per air piston, but only as an option. The primary air closing would be on the existing air regulator.  
         [0025]     A programmed sequential release of water droplets from the manifold is accomplished by the use of a computer which is connected to the trigger circuit as is generally understood in the art. The computer includes a parallel interface to provide a digital machine language word which is interpreted by a decoder. The decoder selects the proper timers in the array of valve assemblies. The timer then opens the power transistor to energize the coil to open the valve assembly. The timers are preset to a controlled time period to close the valve when the proper amount of water has been provided to release the water droplet and concurrently load another hanging droplet ready to fall.  
         [0026]     The computer can be any conventional computer which will provide memory registers for certain calculated data. This data can be in the form of index, row, column, interval between droplets, interrupt and strobe information. Programs can be preprogrammed or various source information can be used to activate the computer to produce the desired image. Source information may be based on the galvanic skin resistance or position of the viewer in respect to the fountain. The computer can also be used to generate electronic sound or control a tape trigging mechanism to play music. As an example the computer can sense the sunrise to turn lights off and darkness to turn lights on; preprogrammed computer color light laser display; and wind speed alter program or shutdown. The programs could be the solid memory punch tape or any of the various program sources which are available. It is also possible to program the manifold to play percussive rhythmic music with the falling water droplets acting as individual sound generation elements falling on water or on the solid base.  
         [0027]     All conduits may be made of any suitable pipes or tubing. Conveniently, the conduits are made of plastic tubing having sufficient strength to contain the compressed air.  
         [0028]      FIG. 2  shows a more detailed view of piston  61 . This piston  61  is useable both for the air activated system of this invention and for more conventional electrically activated pistons. In  FIG. 2A , solenoid  75  provides on and optional off power to the piston  67 . Typically, solenoid  75  may be encased with a metal jacket enclosure.  
         [0029]     For either air solenoids or electric solenoids, adjustment means  77 , shown here as two locking nuts and lock washer, allow for accurate positioning of piston  61  in relation to the valve holds. A sound-absorbing washer  79  may be mounted on top of solenoid  75  as part of the sound abatement system. Pad  81  mounted under the solenoid  75  along the piston shaft helps absorb the shock of the piston  61  moving up and down. Optionally, bracket  83  stops or limits the down closing motion of the piston. Spring  85  drives the piston  61  to a return position when the solenoid  75  is not activated. Roll pin  87 , which may also be a springpin, provides means for connecting lower shaft  89  to the solenoid  75 . This allows for replacement shafts being mounted to the solenoid. Lower shaft  89  may comprise a hollow tube of resin and fiberglass or carbon fiber. Preferably, lower shaft  89  is made as light as possible to reduce the load on the solenoid  75 . A comb pintle  91  is located at the bottom of lower shaft  89  and comprises an array of pintle plugs. These pintle plugs provide positive closure of the valve openings. Opening and closing the valves with the pintle plugs reduces the droplets that form the graphical image.  
         [0030]     In one embodiment, the adjustment of the connecting rod between the air piston and the  9  needle valve is done with a screw turning motion. The air piston has a metal threaded rod protruding from its base. A plastic adaptor is threaded with a female thread and has a vertically slotted shape that has a hole for a spring pin. The tongue for the slot is on the connecting rod to the nine needle part that forms the opening and closing part of the valve.  
         [0031]     The pneumatically operated piston  61  is can be incorporated into the manifolds of a vertical graphical waterfall as is known in the art. Typical such known waterfalls are disclosed in U.S. Pat. Nos. 4,294,406 and 6,557,777, incorporated herein and by reference. As shown in  FIG. 3 , a water manifold having multiple piston  61  is provided with water or other suitable fluid through an intake  95 . The movement of piston  61  is driven to communication link  73  as discussed for  FIG. 1 . The vertical movement of piston  61  opens and closes nozzle values in the bottom of manifold  93 . When the nozzle value is open, a stream of water is discharged through the nozzle and falls vertically. The accumulated affects of the opening and closing of the nozzles results in graphical images  97 . The resolution of the graphic can be controlled by the delay in closing the value nozzle. A longer open time falling in open signal and electrical/mechanic action of piston  61  makes a thicker cluster of water droplets in freefall. It is desirable to be able to adjust this delay after on signal to put back the close time of the value depending on the overall resolving power needed. Course and fine resolutions, and variations in between, are assigned to each graphic of a symbol or kinetic pattern as shown in  FIG. 3 .  
         [0032]     Another factor that influences the quality of the graphic image is the pressure head above the nozzle when the value is opened. Typically, this pressure head is determined by the height of the water in the reservoir of manifold  93 . The height of the water in the reservoir can be controlled in numerous ways as disclosed in U.S. Pat. No. 6,557,777. In an optional embodiment shown in  FIGS. 4A  and B, the pressure head of the fluid level is augmented by an overpressure of air within manifold  93 . The overpressure provided by the air minimizes any differences in local pressures due to local variations and fluid height.  
         [0033]     As shown, an array of electric solenoids or air piston  61  is mounted to a mounting plate  99 . Piston  61  extends from the mounting plate  99  and into pressurized manifold  93 . Seals  119  located at the entry point of piston  61  into manifold  93  allows for sliding movement of piston  61  while providing a barrier to pressurized air escaping from manifold  93 .  
         [0034]     A water level sensor  101  detects water level  103  and communicates the water level data to microprocessor  105 . When water level  103  is at or below a designated height, microprocessor  105  signals water supply valve  107  to open allowing water to flow into manifold  93  from a water pressure supply  109 . The water entering manifold  93  is distributed by plenum  111  to minimize turbulence of the entering water and to avoid splashing. The plenum can be, at times, above or below water level  103 . Plenum  111  has slits or holes along the bottom to provide for relatively even, turbulent-free distribution of the entering water.  
         [0035]     Pressurized air from a pressurized air source  113  is reduced to a desired pressure by regulator  115  or bleeding air from the tank by using a valve. Air hose  117  delivers the regulated pressurized air to manifold  93 . The air overpressure in manifold  93  can be set as desired. However, lower air pressures are generably acceptable and are more convenient for sealing the manifold  93 . Here pressures of less than 5 psig, and as low as 1 to 2 psig, have been found to be suitable.  
         [0036]     An alternative method to pressurize the water vessel is to use a blower. The pressure is regulated by changing the speed of the internal valves, opening and closing louvers, changing the attack angle of the internal valves of the blower or bleeding the air from the pressure vessel by using a valve.  
         [0037]     The operation of graphic waterfalls has inherently been noisy due to the action of numerous moving parts and the subsequent vibrations set up in the fountain itself. Experience shows that the noise problem can be exacerbated by use of the pneumatic driven pistons. Therefore, optional embodiments include the use of sound-absorbing enclosures as shown in  FIGS. 5A and 5B  and also in  6 A and  6 B. As shown in  FIGS. 5A and 5B , piston  61  are mounted on mounting plate  99 . For purposes of this embodiment, mounting plate  99  can be constructed of low-sound transmitting material. Preferably, this material is stiff like fiberglass or carbon, fiberboard or a rubber or some medium to high density normally limp that coats a metal  99 . A sound-absorbent foam enclosure  121  is then mounting over the tops of piston  61  either on top of mounting plate  99  as shown on  FIG. 5A  or enclosing the exposed portions of piston  61  and mounting plate  99  as shown in  FIG. 5B .  
         [0038]     As shown in  FIGS. 6A , B and D, another optional embodiment provides enclosure of even more parts of the graphical waterfall.  FIG. 6A  shows a modular valve body  123 , which encases piston  61  (not shown) and mounting plate  99 . Modular valve body  123  is attached to manifold  93 . A foam jacket  125  is adapted to fully encase the assembly of modular valve body  123  and manifold  93 . Foam jacket  125  is open on the bottom and covers the modular valve accepts the bottom where the water comes out of manifold  93 . As shown in  FIG. 6B , sound jacket  125  can have air vents  127  to allow for airflow in and out of foam jacket  125  thereby providing cooling of the parts contained within the foam jacket  125 . This cooling is especially important in embodiments where electrical/mechanical synoides are used to drive piston  61 . For larger fountains, multiple modular valve body  123  are assembled in connect series. They show in  6 C multiple foam jackets  125  are mounted over the series of modular valve body  123 . As illustrated in  FIG. 6D , foam jackets  125  for a series array of modular valve bodies are also opened on each end to allow adjacent foam jackets  125  to abut each other. End caps  129  are mounted on the outside of the end modules when they are more than one module used.  
         [0039]      FIG. 7  shows an alternative sound enclosure for the module. The material is made from a limp and medium to high-density material like (rubber or foam) that covers  5  sides of the module. It serves to deaden the sound for both the pneumatic and electric-solenoid module. Rubber pads or rubber pads with a shock absorbing springs isolate the vibration of the module from the structure it rests on.  
         [0040]     Another alternative to deadening the sound from the module is to submerge the assembly  61  in water. See  FIG. 8 . Although water has a faster sound transmission speed than air, the clattering of the valves are silenced but the resulting pulse from the escaping air results in a concussion to the tank sides. This is solved by lining the inside of the water tank with some dense material (like lead) or a limp material that is constructed in a way that results in an inner wall to the tank and is separate and independent to the outside wall. Air is evaluated from the cylinder in the tank by using tubes, whose ends extend above the water level surface.  
         [0041]     In compliance with applicable statutes, the invention has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the invention is not limited to the specific features shown and described. The present invention has been described in terms of the preferred embodiment, and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.
Droplet formation in a graphic waterfall fountain is pneumatically controlled. Improvements in the delivery of the water droplets can be obtained by pressurizing the fountain manifold. The fountain can be soundproofed by isolating the solenoid assembly with soundproofing materials or by submersion in water.