Method and system for delaying shift and throttle commands based on engine speed in a marine vessel

1. A method for delaying shift and throttle commands based on engine speed in an electronic shift and throttle system, the method comprising the steps of:

establishing a first threshold engine speed;

determining a position of a control lever which allows an operator to manually control shift and throttle functions;

calculating a shift command based on the position of the control lever and calculating a throttle command based on the position of the control lever;

delaying execution of the shift command by a shift actuator if the engine speed is above the first threshold engine speed; and

delaying execution of the throttle command by a throttle actuator if the engine speed is above the first threshold engine speed.

2. The method as claimed in claim 1 wherein the step of delaying execution of the throttle command includes:

moving the throttle actuator to an idle position to decrease the engine speed; and

delaying execution of the throttle command until after the engine speed falls below the first predetermined threshold engine speed.

3. The method as claimed in claim 2 further including the step of moving the shift actuator to a neutral position prior to execution of the throttle command.

4. The method as claimed in claim 3 wherein the step of moving the shift actuator to the neutral position includes moving the shift actuator to the neutral position after the engine speed falls below the first predetermined threshold engine speed.

5. The method as claimed in claim 1 further including the step of establishing a second threshold engine speed and wherein the step of delaying execution of the shift command includes:

moving the throttle actuator to an idle position to decrease the engine speed;

moving the shift actuator to a neutral position after the engine speed falls below the first predetermined threshold engine speed;

executing the throttle command to increase the engine speed after the shift actuator is moved to the neutral position; and

delaying the execution of the shift command until after the engine speed rises above the second predetermined threshold engine speed.

6. The method as claimed in claim 1 wherein the step of establishing the first threshold engine speed includes establishing the first threshold engine speed at 1,500 RPM.

7. The method as claimed in claim 5 wherein the step of establishing the second threshold engine speed includes establishing the second threshold engine speed between 500 RPM and 1100 RPM.

8. The method as claimed in claim 5 wherein the step of establishing the second threshold engine speed includes establishing the second threshold engine speed at an engine speed lower than the first threshold engine speed.

9. A method for delaying shift and throttle commands based on engine speed in an electronic shift and throttle system, the method comprising the steps of:

establishing a first threshold engine speed and a second engine threshold speed;

determining a position of a control lever which allows an operator to manually control shift and throttle functions;

calculating a shift command based on the position of the control lever and calculating a throttle command based on the position of the control lever;

moving the throttle actuator to an idle position to decrease the engine speed until the engine speed falls below the first threshold engine speed;

moving the shift actuator to a neutral position after the engine speed falls below the first predetermined threshold engine speed;

delaying the execution of the throttle command until after the shift actuator is moved to the neutral position; and

delaying the execution of the shift command until after the execution of the throttle command and the engine speed rises above the second predetermined threshold engine speed.

10. The method as claimed in claim 9 further wherein the step of establishing the first threshold engine speed includes establishing the first threshold engine speed at 1,500 RPM.

11. The method as claimed in claim 9 further wherein the step of establishing the second threshold engine speed includes establishing the second threshold engine speed at between 500 RPM and 1100 RPM.

12. The method as claimed in claim 9 wherein the step of establishing the second threshold engine speed includes establishing the second threshold engine speed at an engine speed lower than the first threshold engine speed.

13. A method for delaying shift and throttle commands based on engine speed in an electronic shift and throttle system, the method comprising the steps of:

establishing a first threshold engine speed at 1,500 RPM and a second engine threshold speed at between 500 RPM and 1100 RPM;

determining a position of a control lever which allows an operator to manually control shift and throttle functions;

calculating a shift command based on the position of the control lever and calculating a throttle command based on the position of the control lever;

moving the throttle actuator to an idle position to decrease the engine speed until the engine speed falls below the first threshold engine speed;

moving the shift actuator to a neutral position after the engine speed falls below the first predetermined threshold engine speed;

delaying the execution of the throttle command until after the shift actuator is moved to the neutral position; and

delaying the execution of the shift command until after the execution of the throttle command and the engine speed rises above the second predetermined threshold engine speed.

14. A method for delaying shift commands when gears are changed in an electronic shift and throttle system based on engine speed, the method comprising the steps of:

establishing a first threshold engine speed and a second threshold engine speed;

determining a position of a control lever which allows an operator to manually control shift;

calculating a shift command based on the position of the control lever;

moving the throttle actuator to an idle position to decrease the engine speed until the engine speed falls below the first threshold engine speed;

moving the throttle actuator to an open position to increase the engine speed after the engine speed falls below the first predetermined threshold engine speed;

delaying the execution of the shift command until the execution of the throttle command and the engine speed rises above the second predetermined threshold engine speed.

15. The method as claimed in claim 14 further wherein the step of establishing the first threshold engine speed includes establishing the first threshold engine speed at 1,500 RPM.

16. The method as claimed in claim 14 further wherein the step of establishing the second threshold engine speed includes establishing the second threshold engine speed at 500 RPM and 1100 RPM.

17. The method as claimed in claim 14 wherein the step of establishing the second threshold engine speed includes establishing the second threshold engine speed at an engine speed lower than the first threshold engine speed.

18. An electronic shift and throttle system for delaying shift and throttle commands based on the speed of an engine, the system comprising:

a sensor for sensing the speed of the engine;

a shift actuator for shifting between a forward gear and a reverse gear through a neutral gear;

a throttle actuator for moving a throttle between an idle position and a wide open throttle position;

a control head including a pivotable control lever for manually controlling shift and throttle functions of the engine, the control lever being moveable through a range of positions;

an engine control unit for calculating a shift command and a throttle command based on a position of the control lever;

an engine servo module for delaying execution of the shift command if the speed of the engine is above a first predetermined threshold engine speed, the engine servo module commanding the throttle actuator to move the throttle to the idle position to decrease engine speed and the engine servo module delaying execution of the shift command until after the engine speed falls below the first predetermined threshold engine speed.

19. The system as claimed in claim 18 wherein the engine servo module commands the throttle actuator to move the throttle actuator towards the wide open throttle position to increase the engine speed after the engine speed falls below the first predetermined threshold speed, and the engine servo module delaying execution of the shift command until the engine speed rises above a second predetermined threshold engine speed.

20. The system as claimed in claim 18 where in the engine servo module commands the shift actuator to shift to the neutral gear after the engine speed falls below the first predetermined threshold engine speed, and the engine servo module the delaying execution of the throttle command until after the shift actuator shifts to the neutral gear.