Abstract:
A fluid injector made of pressure rated components that attach to a fluid flow line so that flow is transferred from the flow line, into the injection unit and back to the fluid flow line. The inlet flow is used to pressurize the storage tank and provide a solution to mix with injection solutions in the tank to provide an accurate preset or adjustable injection rate into the fluid flow line. Vent/proportioner ports provide back flow protection, prevent fluid from siphoning from the storage tank, provide an internal air release port and set injection ratios. A mixing control valve adjusts the injection ratios by mixing outgoing injection solutions with incoming fluid from the fluid flow line. Flexible bladders isolate one or more injection solutions within one storage container which are injected simultaneously at independent injection rates.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     BACKGROUND—FIELD OF INVENTION 
     This invention relates to storage tanks and fluid injection systems, specifically to injection metering devices. 
     BACKGROUND—DESCRIPTION OF PRIOR ART 
     A variety of means have been used to inject fluids into fluid streams. These include metering pumps, water powered pumps, siphon devices, flow through devices and gravity feed drainage equipment. 
     There are a number of problems encountered with each type of equipment available in delivering an accurately proportioned injection amount. Metering pumps are either set to inject a predetermined amount into a fluid stream without a means of adjusting to changes in flow volume in the fluid stream, or they are controlled electronically by flow sensors located in the fluid stream. The components of this type of system are mechanical and electronic so they are subject to wear and mechanical failure. Water powered pumps adjust automatically to changes in flow in the fluid stream but are a mechanical device with a number of seal points. The seals require frequent maintenance for the unit to operate properly. This design is limited in the amount of fluid flow it can operate with and as flows increase, the cost of the device increases. Siphon devices rely on a high restriction in the fluid stream to create venturi suction strong enough to pull the injection solution from the storage container. They require high pressure to operate and the high restriction in the fluid stream greatly reduces the fluid stream volume. Fluctuations in pressure can cause the device to not inject continuously creating uneven distribution. They are also unable to dependably inject solutions such as water-soluble fertilizers without plugging. Venturi systems generally have relatively small flow orifices and the fertilizer solution has a tendency to settle, creating sedimentation that plugs these orifices. Flow through devices typically channel the flow of the fluid stream through a container that holds a soluble product that slowly breaks down, releasing the product into the stream. This method doesn&#39;t control the amount being distributed and can give unreliable distribution. It is common for the soluble products to melt as they sit in the water while the system is not operating and release a large amount when the system is restarted. 
     Several types of fluid injectors have been developed to proportion liquid or soluble fertilizers or chemicals into fluid piping systems. My U.S. Pat. No. 5,484,106, Automatic Pressurized Adjustable Solution Dispenser accomplishes this task but relies on a check valve to prevent back flow of contaminants into the fluid stream. With this design, the outlet flow port connection needs to extend to the bottom of the storage tank to establish a consistent injection rate of fertilizers, which have a higher specific gravity than the incoming water. When the outlet port connection is extended to the bottom of the storage tank, the system develops an air pocket in the top of the storage tank that can only be eliminated by manually filling the tank with fluid or some other means of manually venting the system. If the air is not removed from the system, a potentially hazardous condition exists in that air compresses under pressure, which creates a higher stress on the storage tank than fluids under pressure and can cause the storage tank to rupture at much lower operating pressures. The presence of air also reduces the amount of fluid in the storage tank. This limits the fluid available to mix with soluble products to make them an injectable solution, causing the system to not inject accurately or possibly not inject at all due to plugged flow ports. Since there is no way for air to escape the storage tank, soluble products must be premixed and the tank filled with water before using the system. Many soluble products begin settling to the bottom of the tank immediately after being mixed. Continual agitation is required to keep them in an injectable state. This requires extending the inlet port near the bottom of the storage tank to direct flow through the soluble product. Also, this design does not provide a means of injecting more than one solution from the same tank at independent ratios. 
     The U.S. Pat. No. 4,846,214, Fluid Additive Injector by Thomas F. Strong has an automatic mechanical air relief valve that vents air from the storage tank to the atmosphere. While it does evacuate the air from the tank automatically, it is mechanical in nature so it is subject to wear and eventual failure. It does not provide back flow protection, establish proportioning rates or allow air to be vented through the piping system. It also does not provide a means of injecting more than one solution from the storage tank at independent ratios. 
     The U.S. Pat. No. 3,809,291, Liquid Proportioning System by Chester A. Purdy is a gravity feed system that uses an internal mixing chamber to combine two liquids to be dispensed into a fluid stream. It requires an electrical controller, a pressure switch and a float valve to control fluid flow into the tank. 
     The U.S. Pat. No. 5,544,810, Precision-Ratioed Fluid-Mixing Device And System by Horvath, Abrams and Helf utilizes a high pressure flow line to create a venturi to draw multiple fluids from multiple unpressurized containers and accurately mix them into one solution. The system has an air vent to the atmosphere to prevent siphoning of fluid from the storage containers when the system is not operating. This design requires a high-pressure flow line to create enough vacuum to draw fluids from the containers. This creates a high restriction in the flow line, significantly reducing flow volume and pressure. It also requires multiple containers to store the various solutions, which requires piping connections between all the containers used. This design cannot operate at low pressures or automatically mix dry products and keep them an injectable solution. 
     The U.S. Pat. No. 6,039,065, Fluid Proportioning Valve And Method by John P. Gagliardo is a mixing valve that combines liquids at controllable proportions. It does not provide for the injection of liquids into a flow line, only the mixing of incoming flows. 
     My invention solves a number of problems that have been present in prior art. It eliminates the need for a mechanical check valve and air relief valves, which are subject to wear, leakage and failure. It operates at very low pressures without the need for restriction in the flow line. It operates totally on pressure from the flow line and injects very accurately. It can handle dry products as well as very heavy products without plugging or manual mixing. It can inject multiple solutions at independent injection rates from one storage tank. 
     OBJECTS AND ADVANTAGES 
     Accordingly, the objects and advantages of my invention are: 
     (a) Provides the ability to accurately inject one or more liquid solutions into a fluid stream at independent injection rates. 
     (b) Soluble products can be put in the storage tank dry and the system will exhaust all air from the storage tank while mixing the products automatically, eliminating manual mixing and plugging. 
     (c) Provides back flow and siphoning protection without the need for mechanical check valves and air relief valves, which makes the system more dependable, less expensive to manufacture, have a longer service life and require less maintenance. 
     (d) Flow control allows a wide range of injection rates, which gives the user the ability to apply the products in minutes or over weeks or months. 
     (e) Highly concentrated product can be used, which reduces storage requirements. 
     (f) There are no moving parts to wear out or break. All operations are controlled by system flow. 
     (g) Little exposure to hazardous chemicals. The chemicals can be applied in very low amounts automatically, which eliminates any exposure during the application process as well as better absorption rates, reducing negative environmental impact. 
     (h) Mixing incoming fluid with the outgoing solution makes the injection rate slower so flow ports can be made larger which allows more fluid through the system, which prevents plugging, improves mixing and improves injection accuracy. 
     (i) Inlet connections can be extended to the bottom of the tank to provide agitation of soluble or heavy products, which keeps them in a more injectable state and eliminates the need for manual mixing when the system is initially filled. It also allows a higher concentration of product to be put in the storage tank. 
     (j) Outlet connections can be extended to the bottom of the tank to provide consistent, accurate metering of the injected solution. 
     (k) Provides a consistent injection stream so the injected solution is more evenly mixed in the flow line. 
     (l) Operates at very low flow rates and pressures with no restriction on flow line pressure or volume, giving it a broad range of use in many applications. 
     (m) Responds to the smallest changes in pressure or velocity in the flow line, making it very accurate in all applications. 
     (n) Convenient emptying and filling of single or multiple solutions. 
     Still further objects and advantages will become apparent in the ensuing drawings and description. 
     SUMMARY 
     In accordance with the present invention a fluid injector with vent/proportioner ports comprises a fluid injector that utilizes fluid from a flow line to accurately inject fluids into the flow line. The system mixes incoming fluid with outgoing injection solution to provide a wide range of flow adjustment. It uses flow orifices to provide air release from the storage tank as well as provide back flow protection. It utilizes multiple bladders to inject multiple solutions from one storage tank. 
    
    
     DRAWING FIGURES 
     In the drawings, closely related figures have the same number but different alphabetical suffixes. 
     FIG. 1 shows an overview of the system operating and how it is connected to a fluid flow line. 
     FIG. 2 shows an overview of the system operating during back flow conditions. 
     FIG. 3 shows an overview of the system operating during back flow with vacuum conditions. 
     FIG. 4 shows an overview of the system with multiple bladders. 
     
       
         
               
             
               
               
               
               
             
           
               
                   
               
               
                 Reference Numerals In Drawings 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                  1 
                 fluid flow line 
                  2 
                 inlet connection tube 
               
               
                  3 
                 inlet vent/proportioner port 
                  4 
                 outlet vent/proportioner port 
               
               
                  5 
                 agitation tube 
                  5a 
                 agitation nozzle 
               
               
                  6 
                 pickup filter 
                  7 
                 pickup tube 
               
               
                  8 
                 crossover connection 
                  8a 
                 mixing valve 
               
               
                  9 
                 outlet connection tube 
                 10a 
                 tap fitting 
               
               
                 10b 
                 tap fitting 
                 11 
                 tank inlet connection 
               
               
                 12 
                 tank outlet connection 
                 13 
                 storage tank 
               
               
                 14 
                 tank inlet port 
                 15 
                 tank outlet port 
               
               
                 16 
                 storage tank cap 
                 16a 
                 bladder 
               
               
                 16b 
                 bladder 
                 17 
                 site tube 
               
               
                 17a 
                 fill port 
                 17b 
                 fill port 
               
               
                 17c 
                 fill port 
                 18 
                 drain valve 
               
               
                 19a 
                 fill port valve 
                 19b 
                 fill port valve 
               
               
                 19c 
                 fill port valve 
                 20 
                 flow direction 
               
               
                 21 
                 injection solution 
                 22 
                 injection solution 
               
               
                 23 
                 fluid from flow line 
                 24 
                 injection solution 
               
               
                 25 
                 air 
               
               
                   
               
             
          
         
       
     
    
    
     DESCRIPTION 
     FIGS.  1 , 2 , 3 —PREFERRED EMBODIMENT 
     A preferred embodiment of the fluid injector with vent/proportioner ports is shown in FIG.  1 . This side view shows a basic view of the invention and how it connects to a fluid flow line. The system can be manufactured from various types of plastic, metal or both. Plastic connections can be glued or threaded. Metal connections can be threaded, welded or braised. The tank inlet connection is connected to fluid flow line  1  by attaching inlet connection tube  2  to tapping fitting  10   a.  The tank outlet connection  12  is connected to fluid flow line  1  by attaching outlet connection tube  9  to tapping fitting  10   b.  The tank inlet connection  11  is connected to tank outlet connection  12  by crossover connection  8 . Mixing valve  8   a  is located in the crossover connection  8 , between tank inlet connection  11  and tank outlet connection  12 . The tank inlet connection  11  is attached to tank inlet port  14 , which is attached to inlet vent/proportioner port  3  and agitation tube  5 . Agitation nozzle  5   a  is attached to the end of agitation tube  5 , which extends into the bottom portion of storage tank  13 . The tank outlet connection  12  is attached to the tank outlet port  4 , which is attached to outlet vent/proportioner port  4  and pickup tube  7 . Pickup filter  6  is attached to the end of pickup tube  7 , which extends to the bottom of storage tank  13 . Site tube  17  is located in the outlet connection tube  9  between tank outlet connection  12  and tap fitting  10   b.    
     Operations—FIG. 1,  2 ,  3   
     The method of using the fluid injector with vent/proportioner ports is to connect it to a fluid flow line as shown in FIG.  1 . 
     Once the unit has been installed, shut off all flow in the fluid flow line  1 . Remove the inlet connection tube  2  and outlet connection tube  9  from the storage tank cap  16 . Remove the storage tank cap  16  from the tank and add the material to be injected, to the storage tank  13 . Put the storage tank cap  16  on the tank and attach the inlet connection tube  2  and outlet connection tube  9  to the storage tank cap  16 . Adjust the mixing valve  8   a  to desired injection rate and turn on flow in fluid flow line  1 . 
     When the system is operating, a positive pressure is created by tap fitting  10   a  creating fluid flow from fluid flow line  1 , which is directed through inlet connection tube  2  to tank inlet connection  11 . The fluid is then directed through crossover connection  8  to the tank outlet connection  12  and through tank inlet port  14  to storage tank  13 . The amount of flow to each area is controlled by mixing valve  8   a.  As mixing valve  8   a  is opened, more fluid flows through crossover connection  8  and less fluid through tank inlet port  14 . This reduces the amount of fluid leaving the storage tank  13  which reduces the concentration of the fluid injected into the fluid flow line  1 . The fluid entering the storage tank  13  through tank inlet port  14  flows through inlet proportioner/vent port  3  to the top of storage tank  13 . The size of the inlet proportioner/vent port  3  determines the amount of flow diverted to the top and bottom of the storage tank  13 . This controls the amount of agitation action directed at injection solution  24 . The balance of the fluid entering the storage tank  13  is directed through the agitation tube  5 , through agitation nozzle  5   a,  into the bottom of the tank and into the injection solution in the bottom of the tank. By directing the inlet flow to the bottom of the tank, dry soluble products are mixed automatically with inlet fluid from fluid flow line  1  as the storage tank  13  is filling. The air in storage tank  13  is exhausted through outlet vent/proportioner port  4  into the fluid flow line  1 . Since air moves more easily than liquid, no fluid leaves the storage tank  13  until all the air has been exhausted. This provides thorough mixing of injection solution  24  which creates accurate injection and prevents plugging. 
     Flow entering storage tank  13  pressurizes storage tank  13  to the same pressure as the fluid flow line  1 . A negative pressure is created by tap fitting  10   b  creating flow from storage tank  13 . This flow is directed through pickup filter  6  through pickup tube  7  as well as through vent/proportioner outlet port  4  to tank outlet port  15 . The size of the vent/proportioner outlet port  4  determines the mix ratio of fluid inside the storage tank  13  and injection solution  20 . It then flows through crossover connection  8 , where it mixes with inlet flow and then flows through tank outlet connection  12  to tap fitting  10   b  through outlet connection tube  9 . 
     Tap fittings  10   a  and  10   b  do not create any restriction in flow line  1 . Because the storage tank  13  is pressurized to the same pressure as flow line  1 , any changes in flow line  1  pressure or velocity is communicated to storage tank  13  immediately, making the system very responsive to changes in flow and very accurate. This also enables the system to begin operating with as little as two gallons per hour flow in fluid flow line  1  and at as little as 5 PSI operating pressure. The system has no capacity or volume restrictions. If flow restriction is put between tap fitting  10   a  and tap fitting  10   b,  the operating range is increased. It can be adapted to any size application. Because the flow through the system is consistent, not pulsating, the injection solution  24  entering the fluid flow line  1  is consistent throughout the fluid flow line  1  solution. 
     When the system is operating, injection flow can be seen through site tube  17 . When material is no longer visible in site tube  17 , the system is empty and ready for refill. 
     FIG. 2 shows the flow pattern when a back flow condition exists. To create a back flow condition, pressure is lost in fluid flow line  1  so any fluid in the fluid flow line  1  reverses direction. This reverses the flow through the system by creating a positive pressure at tap fitting  10   b.  This directs flow into the storage tank through the fertilizer outlet tube  9 , the tank outlet connection  12  and then through the tank outlet port  15  and crossover connection  8 . The adjustment valve  8   a  setting determines the amount of fluid that reenters the storage tank. 
     The more open the mixing valve  8   a  is set, the more fluid that will bypass the storage tank  13  and return to the fluid flow line  1  through the inlet connection tube  2 . The fluid that does not go through the crossover connection  8  will flow into the storage tank  13  through the tank outlet port  15 . This directs the fluid to the top of the tank and back out of the tank through the vent/proportioner inlet port  3 . Since there is a loss of pressure in a back flow condition, there is much less flow in the fluid flow line  1 . This enables the vent/proportioner ports  3  and  4  to handle all incoming and outgoing flow, preventing any toxic material from the bottom of the tank from entering the fluid flow line  1 . 
     FIG. 3 shows how the system operates when all the fluid has been eliminated from the fluid flow line  1 . The fluid is replaced by air which creates a vacuum condition. The air follows the same flow path as the fluid does during back flow conditions. Once air has entered the storage tank  13  through tank outlet port  4 , it flows through the inlet vent/proportioner port  3  to the fluid flow line  1 . Because air flows more easily than fluid, only air flows through the system. This puts the system in an air lock condition which prohibits any liquid from leaving the storage tank  13 . 
     To refill the unit, shut off all flow in the fluid flow line  1 . Relieve pressure from the storage tank  13  by opening a valve downstream in the fluid flow line  1  or by slowly removing the outlet connection tube  9  from the storage tank cap  16 . Once pressure has been relieved, remove inlet connection tube  2  and outlet connection tube  9  from the storage tank cap  16 . Remove the storage tank cap  16  from the tank and pour out the fluid in the storage tank  13 . Add the material to be injected, to the storage tank  13 . Put the storage tank cap  16  on the tank and attach the inlet connection tube  2  and outlet connection tube  9  to the storage tank cap  16 . Adjust the mixing valve  8   a  to the desired injection rate and turn on flow in fluid flow line  1 . 
     FIG.  4 —Additional Embodiment 
     An additional embodiment is shown in FIG.  4 . It shows the addition of bladder  16   a  and  16   b.  Bladder  16   a  is connected to vent/proportioner port  4   a  that is connected to tank outlet port  4 . Bladder  16   b  is connected to vent/proportioner port  4   b  that is connected to tank outlet port  4 . Fill port  17   a  is connected to bladder  16   a.  Fill port  17   b  is connected to bladder  16   b.  Fill port  17   c  is connected to storage tank  13 . Drain valve  18  is connected to storage tank  13 . Fill port valve  19   a  is connected to fill port  17   a.  Fill port valve  19   b  is connected to fill port  17   b.  Fill port valve  19   c  is connected to fill port  17   c.    
     FIG.  4 —Operations 
     The method of using the fluid injector with vent/proportioner ports as shown in FIG. 4 is to turn off all flow in fluid flow line  1 . Relieve system pressure by opening a valve downstream in the fluid flow line  1 . When the pressure is relieved, close the valve. Drain all fluid from storage tank  13  by opening drain valve  18  and fill port valve  19   c.  When all fluid has been drained from storage tank  13 , close drain valve  18 . Open fill port valve  19   a  and pour injection solution  21  into bladder  16   a.  When the desired quantity of injection solution  21  has been poured in, close fill port valve  19   a.  Open fill port valve  19   b  and pour the desired amount of injection solution  22  into bladder  16   b.  When the desired quantity of injection solution  22  has been poured in, close fill port valve  19   b.  Pour the desired amount of injection solution  20  in fill port  17   c.  When the desired amount of solution has been poured in, close fill port valve  19   c.  Open the valve to allow flow into fluid flow line  1 . 
     When the system is operating, fluid from the fluid flow line  1  enters the storage tank  13  through the tank inlet port  14  and the crossover connection  8 . The fluid entering the tank pressurizes the storage tank  13 , bladder  16   a  and bladder  16   b.  The negative pressure created by tap fitting  10   b  along with the positive pressure created by tap fitting  10   a  create flow from bladder  16   a,  bladder  16   b  and storage tank  13 . Bladder  16   a  and bladder  16   b  are made of flexible material that collapses as fluid is removed. They are used to contain injection solutions that need to be separated due to their reaction to other solutions in the storage tank  13  or if their specific gravity is the same or lighter than the fluid entering the storage tank  13  from the fluid flow line  1 . As injection solution  21  leaves bladder  16   a  and flows through tank outlet port  15 , it is premixed with fluid from storage tank  13  to a preset ratio determined by the orifice size of the outlet vent/proportioner port  4   a.  As injection solution  22  leaves bladder  16   b  and flows through tank outlet port  15 , it is premixed with fluid from storage tank  13  to a preset ratio determined by the orifice size of the outlet vent/proportioner port  4   b.  All solutions leaving storage tank  13  are then mixed with the fluid in crossover connection  8 . Mixing valve  8   a  sets the injection ratio for the combined solutions before they enter fluid flow line  1 . 
     SUMMARY, RAMIFICATIONS, AND SCOPE 
     Accordingly, the reader will see that the fluid injector with vent/proportioner ports will provide many advantages to consumers, industry and the environment. It provides an economical means of accurately injecting solutions that are normally difficult to inject. It can inject multiple solutions simultaneously into a flow line, each with their own injection ratio. Incompatible products can be combined in one tank and one installation. It is very easy to use and has a long service life with very low maintenance requirements. It easily adapts from small to large applications. It can be manufactured easily and economically from products readily available in the marketplace. It can be fabricated from plastic or metal piping components or molded. 
     While the above description contains many specificities, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of one preferred embodiment thereof. Many other variations are possible. For example additional crossover connections with control valves could be added to provide specific flow adjustment for all solutions in the storage tank. The crossover connection and control valve could be eliminated and the proportioning rates set only by the vent/proportioner ports. The agitation tube could be removed for products that are lighter and easier to inject. The system can accommodate filling and draining with ports sealed by valves, plugs or caps. The system can have the fluid flow line attach to it or have it attach remotely. It can be designed to attach to the end of a fluid flow line of any type. 
     Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents.