Fuel trim system for multiple drive propulsion systems

Abstract

An apparatus to monitor fuel, thrust, engine and vessel speed on marine vessels. Sensors measure the thrust forces developed by each of the ship's propellers. The system compares the thrust produced to the gallons of fuel consumed by each system and prompts the vessel's operator to make the proper throttle adjustment for each drive system to insure that the system with the best thrust to fuel ratio makes the largest contribution to the total thrust force required to maintain vessel speed.

1 . A fuel trim system for minimizing fuel consumption on a marine vessel with multiple drive propulsion systems while maintaining a predetermined steady state speed comprising: 
 a thrust sensor disposed on each drive system;    a fuel flow meter disposed on each drive unit;    a tachometer disposed on each drive unit;    a global positioning system;    a microprocessor in electrical communication with the thrust sensors, the flow meters, the tachometers and the global positioning system;    an operator display module located at the operator control station.    
   
   
       2 . The fuel trim system as set forth in  claim 1 , said microprocessor comprising the means for acquiring the thrust data from said thrust sensors, the engine speed data from said tachometers and the vessels speed data from said global positioning system.  
   
   
       3 . The fuel trim system as set forth in  claim 1  said microprocessor further comprising the means to calculate total thrust forces generated by the vessel while underway.  
   
   
       4 . The fuel trim system as set forth in  claim 1  said microprocessor further comprising the means to calculate the total fuel consumed by the vessel while underway.  
   
   
       5 . The fuel trim system as set forth in  claim 1  said microprocessor further comprising the means to calculate the total thrust consumed by the vessel while underway.  
   
   
       6 . The fuel trim system as set forth in  claim 1  said microprocessor further comprising the means to calculate the efficiency of each drive unit in units of thrust force per gallon of fuel.  
   
   
       7 . The fuel trim system as set forth in  claim 1  said microprocessor further comprising the means to compare the efficiencies of each drive unit and send a corresponding output signal to the control system.  
   
   
       8 . The fuel trim system as set forth in  claim 1  said microprocessor further comprising the means to send signals to the a display and further prompt the operator to effect increases or decreases in throttle positions in such a manner that the system with the best thrust to fuel ratio makes the largest contribution to the total thrust force required to maintain a constant predetermined vessel speed.  
   
   
       9 . The fuel trim system as set forth in  claim 1 , said operator display module in electrical communication with said microprocessor.