Patent Publication Number: US-2005130514-A1

Title: Simplified flushing system

Description:
BACKGROUND OF THE INVENTION  
     FIELD OF THE INVENTION  
      This invention relates to a novel, yet simple system and process for flushing outboard marine propulsion systems with a desired fluid. This flushing system and process allows a person to quickly and easily flush an engine with or without the engine running and with the vessel in or out of the water.  
      The need for such a system is commonly seen with marine engines. When a marine engine is operated, in fresh water or salt water, impurities in the water can cause cooling problems and corrosion of components if not properly flushed. Debris of various types can be picked up in lakes and rivers, and even the cleanest ocean water is going to have salt in it. Therefore, it is imperative that marine engines get flushed after every use.  
      The difficulty is that flushing marine engines can be very cumbersome since the intake for cooling fluids is in the outdrive near the propeller. To flush an engine like this, the vessel&#39;s operator has to put “earmuffs” over the outdrive&#39;s intake vents to supply water for flushing. Placing the earmuffs on an outdrive can be cumbersome and even dangerous.  
      Some outboard engines have a flush port that is located closer to the engine portion of an outboard, on the engine cowl for example. This flush port allows for a much simpler connection of a hose to supply water for flushing the engine. The problem with this approach is that the engine cannot be run during the flushing process because of the need to supply water to the impeller pump when the engine is running. Under the right set of circumstances, it is possible to run the engine during the flushing process, even thought the engine manufacturers advise against it. If the water supply is high enough to supply more water than the engine can handle, to the point where a certain backpressure is created, the backpressure will force water backwards through the impeller pump and keep it lubricated and cool. However, if the supply of water is reduced to the point where there is not an excess, creating backpressure, the water will not be forced backwards through the impeller pump, and the pump will overheat, run dry, and ruin the impeller. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is an external view of a typical outboard marine propulsion system, with an engine located above the drive unit. The figure shows the seawater intake and an example of an outboard engine with a flush port. The flush port shown in the figure is also representative of the position of an embodiment of the current invention.  
       FIG. 2  is the external view of a manual embodiment of the current invention.  
      The embodiment has positioning, locking, and retaining means that are used to keep the system in place and oriented correctly when the engine is running, and when the engine is being flushed.  
       FIG. 3  is a cross sectional view of  FIG. 2 . The figure shows the internal features of the flushing system. The flushing system&#39;s positioning, locking, and retaining means are shown, as well as the fluid retaining, sealing, and regulating means.  
       FIG. 4  is an embodiment of the flushing system shown in the orientation that it would be in during normal operation of the vessel. The view also show the direction that seawater would travel as is leaves the seawater pump, flows through the flushing system, and then flows to the engine.  
       FIG. 5  is an embodiment of the flushing system shown in the orientation that it would be in during the flushing operation of the vessel. The view also shows the direction that the flushing fluid would travel as it enters the flushing system through the hose, travels through the flushing system, and then travels to the engine and back down through the seawater pump.  
       FIGS. 6 and 7  show a couple of possible embodiments of the regulating means. This is the portion of the flushing system the creates the backpressure necessary to ensure that the seawater pump remains lubricated with flushing fluid and cool while the engine is running. 
    
    
     SUMMARY OF THE INVENTION  
      The invention eliminates the difficulty of the flushing process by allowing for a convenient topside flush port or automatic system that maintains a certain backpressure so that the engine can be run during the flushing process, and the seawater pump will always have enough water to keep it lubricated and cool. This system is accessed from the topside of the boat, is simple to use, and inexpensive. The novelty of this invention is in its versatility and its simplicity.  
      Previous flushing systems rely on using an “earmuff” style flusher to introduce flushing fluid to the intakes, or using a flushing port with the flushing fluid being introduced to the engine. The “earmuff” style flushers will work in almost any circumstance if used correctly; however, they are difficult to work with, are subject to falling off or being pulled away from the intakes during flushing, and are potentially dangerous due to their proximity to the propellers. The flush port connections are much more accessible; however, if the water supply volume and/or pressure is not high enough, or drops in the middle of the flushing cycle, the impeller water pump will run dry be ruined. This invention solves this problem by forcing enough of the cooling fluid supplied to the flush port back through the impeller pump thereby keeping it cool and lubricated.  
      Another problem with trying to use flush ports is that the pressure needed to force water through the impeller pump varies dramatically with the size of the impeller pump. Larger engines have larger impeller pumps than smaller engines. The pump vanes in large impeller pumps are generally more flexible than the vanes in small impeller pumps. The increase in vane flexibility lowers the backpressure needed to force water back through the pump; therefore, smaller engines tend to need higher backpressures to ensure the impeller pump remains lubricated and cool. The current invention can be designed to work for a specific engine and impeller pump; therefore, the current invention eliminates the reliance on maintaining the volume and/or pressure of the external flushing fluid.  
      This invention provides a simple, inexpensive, and reliable method for thoroughly flushing marine propulsion systems that is not subject to the aforementioned deficiencies.  
      The current invention is primarily used on a marine outboard engine with a seawater pump in the drive portion. The invention can be used with or without the engine running and with the vessel either in or out of the water. The novelty of this invention is in its versatility and its simplicity.  
      The flushing system can be situated anywhere on the vessel, but in the preferred embodiment it is located within the outboard drive unit between the seawater pump and the engine along the usual flow path that cooling fluids travel,  FIG. 1, 10   a.  During normal operation, the flushing system allows flushing fluid to travel into the system, by the regulating means, and on to the engine,  FIG. 4 . The system is kept in this position by the system positioning, retaining, sealing, and locking means shown in  FIGS. 2 and 3 .  
      When it is time to flush the engine, the engine is momentarily turned off, the engine is then leaned forward so that the intakes are out of the water; if the vessel is out of water then the engine does not need to be leaned forward. The fluid retaining means is removed, and a flushing fluid conduit, hose, is attached to the flushing system. After the hose is attached, the flushing system with attached hose is rotated 180° degrees so that it is now in the position shown in  FIG. 5 , and the flushing fluid and engine are turned on. In the embodiment shown, this will happen automatically; as the flushing fluid hose is screwed into the flushing system, the system will rotate and lock into the position needed for flushing. There are currently a number of engine manufacturers that produce their own version of a flush port, with and without a built in hose adapter. This invention can be designed to work with any of those style adaptors; however, the simplest version is shown here.  
      As shown in  FIG. 5 , the fluid regulating means will restrict the flow of fluid to the engine. It will direct the fluid towards the seawater pump in the outdrive section of the engine. Fluid will travel along this path until it fills the entire conduit between the seawater pump and the flushing system. Once the fluid fills this section the pressure will rise rapidly until the point where the fluid regulating means opens and allows fluid to travel to the engine. This entire process usually takes a fraction of a second. Once the engine is started, the fluid regulating means will keep the backpressure between the flushing system and the seawater pump at the specified design pressure for that engine. This constant level of backpressure will ensure that the impeller in the seawater pump remains lubricated and cool despite the possible, (inevitable), changes in the inlet volume and/or pressure of the flushing fluids.  
      Once the flushing process is complete, the flushing fluid can be turned off, the hose remove, the fluid retaining means reattached, and the flushing system rotated back to its original position,  FIG. 4 . The novelty, and simplicity, of this system is that it compensates for inadequate flushing fluid flow and/or pressure with the fluid regulating means. It also compensates for operator error. If the vessel operator leaves the system in the wrong position, the vessel will operate and be flushed just fine. If the vessel&#39;s operator removes the flushing fluid hose, replaces the fluid retaining means, but leaves the flushing system is in the flushing position,  FIG. 5 , the vessel will operate just fine. Cooling fluid from the seawater pump will travel to the flushing system and will stop at the fluid regulating means. The fluid will then travel around the flushing system, between the sealing means and into the opening opposite the seawater pump. Also, once the backpressure reaches the regulating means cracking pressure, the regulating means will open and allow the fluid to travel to the engine. Since the cracking pressure is low relative to the pressure that the seawater pump produces under normal operation, the regulating means does not interfere with normal operation.  
      If the opposite happens, the vessel&#39;s operator attaches the flushing fluid hose but leaves the flushing system in the run position,  FIG. 4 , and tries to flush the engine; the vessel will operate just fine. When the flushing fluid is turned on, it will run into the regulating means and flow around the sealing means into the opening that is facing the seawater pump. Since the fluid will be under pressure and traveling in the direction back towards the seawater pump, enough backpressure will be created to keep the impellers in the seawater pump lubricated and cool. This scenario is much less likely to happen since it is not possible to connect the flushing fluid hose without the flushing system rotating and locking into the flushing system position; however, accidents do happen, so this system is designed to handle them.  
      The embodiment shown in these figures is done in a way that helps illustrate the features of the current invention. The pressure regulating means shown in  FIGS. 6 and 7  are just a few of the examples of possible pressure regulating means. The current invention covers any method that employs either an adjustable or fixed, manual or automatic regulating means that is specifically designed for the purpose of regulating the backpressure of fluid to the seawater pump.  
      The embodiment shown here is one that balances flexibility with cost and convenience. If the motor designer wanted to make the system foolproof and very simple, another embodiment of the current invention would simply be a fixed fluid regulating means that maintains a given pressure of fluid leaving the seawater pump.  
      This way, there is no need for the vessel&#39;s operator to do anything before flushing the engine other than attaching the flushing fluid hose. Since the cracking pressure is low relative to the pressure that the seawater pump produces under normal operation, the regulating means does not interfere with normal operation.  
      Another embodiment of this invention could be used if the engine designer wanted to have an automated flushing cycle. Since this system is based on creating backpressure in the cooling system so as to force water back through the impeller pump, a pressure regulator with a controller would do very well. The designer could use any number of currently known methods of pressure regulation and have a system that automatically controlled the backpressure in the cooling system. This embodiment could be designed to work on the inlet or the outlet side of the engine. All that has to happen is that backpressure is created in the system so that cooling fluid is forced back through the impeller pump keeping it cool and lubricated.  
     DETAILED DESCRIPTION OF AN EMBODIMENT  
       FIG. 1  shows the general layout of an outboard, OB, marine motor  2 . A typical OB has a water intake  18  for taking in cooling water for the engine. The water pump  12  pumps the cooling water to the engine  5 , and after it has gone through the engine  5 , the discharged water  22  is sent back out to the body of water that it came from.  
      After the OB motor  2  has been used, it is a good and recommended practice to flush the engine  5  as well as other cooling system components such as the intake  18 , the pump  12 , inlet passageway  20 , and the discharge passageway  22 . Many OB motors  2  have an access port  15  for attaching a hose that is used to deliver clean water to flush the OB motor  2  after use. To help flush the OB motor  2 , the flushing system  10  can be installed either before the engine  5 ,  10   a,  or after the engine  5 ,  10   b,  depending upon how the flushing system  10  is going to fit in with the OB motor  2  design.  
       FIG. 1  shows two possible locations for the flushing system. The first is position places the flushing system  10   a  before the engine  5 . An embodiment of the flushing system  10   a  is shown in  FIGS. 2 and 3 .  FIG. 4  shows the flushing system  10   a  inserted between the intake  18  and the engine  5 . The cooling water inlet passageway  20  brings cooling fluid to the flushing system  10   a  and then the cooling water passageway  24  take the fluid from the flushing system  10   a  and sends it to the engine  5 .  
      During normal operation of the OB  2 , the cooling water from passageway  20  enters the flushing system  10   a  and runs into the regulating means  75  and is diverted towards the engine  5 . The flushing system  10   a  is held in place by a retainer  35  and oriented by use of an orienting means  25  and  40 . The orienting means is a pin  40  that rides in a groove  25  that only allows a 180° range of motion for the flushing system  10   a.  The flushing system  10   a  has cover  30  the seals against a cover seal  45  that keeps fluid from leaking out. There are also seals  60  that keep fluid from leaking out of the OB motor  2 , from bypassing the flushing system  10   a.    
       FIG. 5  shows the flushing system during a flushing cycle. When it is time to flush the OB motor  2 , the cover  30  of the flushing system  10   a  is removed, and a hose  90  is attached to the flushing system  10   a  by the threads  65 . The hose  90  seals on the hose seal  70  so that it will not leak. The flushing system  10   a  is then rotated 180° and the water is turned on so that the hose  90  is now supplying cooling fluid to the motor. When the cooling fluid enters the flushing system  10   a,  the pressure regulating means  75  diverts the water back down the inlet passageway  20  until it runs into the intake pump  12 . As soon as the passageway  20  fills it will begin to increase in pressure until the pressure regulating means  75  opens and allow the excess water to flow through passageway  24  and on to the engine  5 . After the hose  90  begins supplying cooling fluid to the OB motor  2 , the OB motor  2  can be started so the entire engine  5  gets flushed with clean water. The pressure regulating means  75  creates pressurized cooling fluid  28  that travels back down passageway  20  and is forced back though the intake pump  12  to keep it cool and lubricated, while allowing the bulk of the cooling fluid to travel through passageway  24  and on to the engine  5 .  
      When the flushing cycle is finished. The OB motor  2  is turned off, the hose  90  is unscrewed from the flushing system  10   a,  the cover  30  is screwed back onto the flushing system  10   a , and the flushing system  10  a is rotated back 180° to its original position as seen in  FIG. 4 .  
       FIGS. 6 and 7  show two examples of simple pressure regulating means. A flexible membrane  76   a  is shown prior to being pressurized and once it sees pressure from the cooling fluid, it would begin to open up  76   b.  Instead of a flexible membrane  76   a,  and hinged plate with a tensioning means could be used,  78   a.  When cooling fluid pressurizes the hinged plate, it would open  78   b.    
      This embodiment of the flushing system  10  uses a very simple manual method of flushing a OB motor  2 . This manually activated pressure regulator could easily be replaced by a number of automatic regulators if the OB motor designers wanted an automatic flushing cycle. There are many versions of pressure regulators and controls that would allow the OB motor  2  designers to create an automated system.  
      If the OB motor designers wanted to use a controllable regulator, they could also design the flushing system  10  to be inserted after the engine  5  in the discharge path  22 . Cooling fluid that was supplied to the engine  5  would leave the engine  5  and enter the flushing system  10   b . During normal operation the water picked up by the water intake  18  and sent through the engine  5  by the pump  12  would pass through the flushing system  10   b  and leave through passageway  22 . However, during an automated flushing cycle, the OB motor  2  would control the flushing system  10   b . Cooling fluid would be supplied to the OB motor  2  through a hose  90  attached to a standard flush port  15 . The cooling fluid that was supplied by the attached hose  90  would pass through the engine  5  and into the flushing system  10   b . The flushing system  10   b  would create backpressure in the passageway  26 , the engine  5 , and force cooling fluid back through passageway  20  and through the pump  12  keeping it cool and lubricated.