Fuel economy system and method for a vehicle

1. A fuel economy system connectable to a throttling means of a vehicle and to an engine control unit connected to an engine of the vehicle, the throttling means generating an unmodified throttling signal having a throttling signal voltage in an unmodified throttling signal voltage range between a minimum throttling signal voltage and an unmodified maximum throttling signal voltage in response to a throttling input between a minimum throttling input and a maximum throttling input received by the throttling means, the engine control unit increasing and decreasing an engine power output of the engine, and thereby an amount of fuel consumed thereby, as the throttling signal voltage and throttling input both respectively increase and decrease, the system comprising:

a sensor for sensing a mass of a load carried by the vehicle; and

a signal control unit connected to said sensor and connectable to said throttling means and said engine control unit, said signal control unit, when said mass sensed by said sensor is within a pre-determined mass range below a pre-determined load mass value, reducing a range of said engine power output for said throttling input from an unmodified engine power output range having a minimum engine power output corresponding to said minimum throttling input and an unmodified maximum engine power output corresponding to said maximum throttling input to a modified engine power output range between said minimum engine power output and a modified engine power output corresponding to said maximum throttling input and below said unmodified throttling input, thereby gradually reducing said engine power output, compared to said unmodified engine power output, for said throttling input and the amount of fuel consumed when said mass is in said pre-determined mass range.

2. The system of claim 1 , wherein, when said mass sensed is within said pre-determined mass range, said signal control unit converts the unmodified throttling signal into a modified throttling signal having a modified throttling signal voltage in a modified throttling signal voltage range between the minimum throttling signal voltage corresponding to the minimum throttling input and a modified maximum throttling signal voltage corresponding to the maximum throttling input and modified maximum engine power output and lower than said unmodified maximum throttling signal voltage corresponding to said unmodified maximum engine power output, thereby limiting the engine power output of the engine to the modified engine power output.

3. The system of claim 1 , wherein said sensor is a sensor disposed under the load and configured for detecting the mass thereof.

4. The system of claim 1 , wherein said sensor is a pressure sensor connected to a suspension disposed underneath the load and upon which the load is carried, the mass being determined by the pressure sensor by measuring a deformation of said suspension caused by pressure of the mass upon said suspension.

5. The system of claim 1 , wherein said sensor is a pressure sensor connected to at least one tire disposed underneath the load and upon which the load is carried, the sensor determining the mass by measuring pressure within the tire and exerted thereupon by the mass.

6. The system of claim 1 , wherein said sensor senses a linear acceleration of the vehicle and determines the mass based on an effect of the mass on said linear acceleration.

7. The system of claim 1 , wherein said sensor senses an angular acceleration of at least one driveline component of the vehicle and determines the mass based upon an effect of the mass on said angular acceleration.

8. The system of claim 1 , wherein, for the unmodified throttle signal voltage range and said modified signal voltage range, the minimum throttle signal voltage is about 0 volt of direct current, the unmodified maximum throttling voltage for the unmodified throttle signal voltage range is about 5 volts of direct current, and, for said modified throttle signal voltage range, said modified maximum throttle signal voltage is about 3.5 volts of direct current,

9. The system of claim 1 , wherein said modified maximum throttling signal is configured, for when said mass is within said predetermined mass range, to be sufficient to cause said engine control unit to allow a modified maximum engine power output sufficient top carry said mass in said range between speeds of about 55 mph and about 70 mph.

10. The system of claim 1 , wherein said signal control unit is further connectable to a transmission of the vehicle, said transmission being connected to the engine control unit and the engine and providing an unrestricted shift schedule of gears for the engine, in which the engine may be shifted into uppermost gears in which said maximum engine power output is accessible, thereby providing access to said unmodified engine power output range, and a restricted shift schedule in which shifting of the engine into the uppermost gears is restricted and the engine power output is limited to said modified engine power output range, said signal control unit automatically selecting said restricted shift schedule when the mass detected by the sensor is within a said pre-determined mass range and automatically selecting said unrestricted shift schedule when the mass detected by said sensor is outside said pre-determined mass range.

11. The system of claim 10 , wherein said transmission has a switch for selecting between said restricted shift schedule and said unrestricted shift schedule, said signal control unit being connectable to said switch for connecting said signal control unit to said transmission, said signal control unit selecting between said restricted shift schedule and said unrestricted shift schedule with said switch.

12. The system of claim 11 , wherein said signal control unit transmits a signal to said switch for actuating said switch to select between said restricted shift schedule and said unrestricted shift schedule.

13. A fuel economy method for a vehicle having a throttling means and an engine control unit connected to an engine of the vehicle, the throttling means generating an unmodified throttling signal having a throttling signal voltage in an unmodified throttling signal voltage range between a minimum throttling signal voltage and an unmodified maximum throttling signal voltage in response to a throttling input between a minimum throttling input and a maximum throttling input received by the throttling means, the engine control unit increasing and decreasing an engine power output of the engine, and thereby an amount of fuel consumed thereby, as the throttling signal voltage and throttling input both respectively increase and decrease, the method comprising the steps of:

a) sensing whether the mass of a load carried by the vehicle is within a pre-determined mass range; and

b) when the mass of the load is within the pre-determined mass range below a pre-determined load mass value, reducing a range of said engine power output for said throttling input from an unmodified engine power output range having a minimum engine power output corresponding to said minimum throttling input and an unmodified maximum engine power output corresponding to said maximum throttling input to a modified engine power output range between said minimum engine power output and a modified engine power output corresponding to said maximum throttling input and below said unmodified throttling input, thereby gradually reducing said engine power output and said fuel consumed, compared to said unmodified engine power output and fuel consumed, as said throttling input approaches said maximum throttling input when said mass is in said pre-determined mass range.

14. The method of claim 13 , wherein said signal control unit is further connectable to a transmission of the vehicle, said transmission being connected to the engine control unit and the engine and providing an unrestricted shift schedule of gears, in which the engine may be shifted into uppermost gears in which said maximum engine power output is accessible, thereby providing access to said unmodified engine power output range, and a restricted shift schedule in which shifting of the engine into the uppermost gears is restricted and the engine power output is limited to said modified engine power output range, and step b) comprises the step of

e) when the mass detected by the sensor is within said pre-determined mass range, automatically selecting said restricted shift schedule.

15. The method of claim 13 , wherein step a) comprises the steps of:

f) measuring a deformation caused by a pressure exerted by the mass on a suspension upon which the load is carried; and

g) based on said deformation, determining said mass.

16. The method of claim 13 , wherein said step a) comprises the steps of:

h) measuring a pressure exerted by the mass on at least one tire upon which the mass is carried; and

i) based on said pressure, determining said mass.

17. The method of claim 13 , wherein said step a) comprises the steps of:

j) measuring a linear acceleration of the vehicle; and

k) determining said mass based on an effect of said mass on said linear acceleration.

18. The method of claim 13 , wherein said step a) comprises the steps of:

l) measuring an angular acceleration of at least one driveline component of the vehicle; and

m) determining said mass based on an effect of said mass on said, angular acceleration.

19. The method of claim 13 , wherein step b) comprises the steps of:

c) when the mass of the load is within the pre-determined mass range, converting the unmodified throttling signal into a modified throttling signal having a modified throttling signal voltage in a modified throttling signal voltage range between the minimum voltage and a modified maximum throttling signal voltage lower than the unmodified maximum throttling signal voltage; and

d) transmitting the modified throttle signal to the engine control unit, thereby progressively lowering the engine power output, and thereby fuel consumed, in response to the throttling input with the modified throttling signal compared to the engine power output generated in response to the unmodified throttling signal as the throttling input increases towards the maximum throttling input.

20. The method of claim 19 , wherein, for the unmodified throttle signal voltage range and said modified signal voltage range, the minimum throttle signal voltage is about 0 volts of direct current, the unmodified maximum throttling voltage for the unmodified throttle signal voltage range is about 5 volts of direct current, and, for said modified throttle signal voltage range, said modified maximum throttle signal voltage is about 3.5 volts of direct current.