Adaptable sensorless end of stroke detection system and method

1. A method of controlling a motor for driving a pump comprising:

providing energy to a motor;

sensing a parameter indicative of current;

wherein the current includes an inrush current and a main draw current of the motor,

determining the end of the inrush current;

determining a start point that is after the inrush current and that is at about the beginning of the main current draw;

determining an end point at about the end of the main current draw;

continuing to provide energy to the motor for a time period that is a function of the time from the start point to the end point; and

de-energizing the motor.

2. The method of claim 1 wherein the parameter indicative of current is a function of the voltage.

3. The method of claim 1 wherein the parameter indicative of current is a function of power.

4. The method of claim 1 wherein the parameter indicative of the current is a function of time.

5. The method of claim 1 wherein the start point is at about the beginning of an increase in current.

6. The method of claim 1 wherein the end point is at about the beginning of leveling off of current.

7. The method of claim 1 wherein the time period is about one-half of the time from the start point to the end point.

8. The method of claim 1 further comprising coupling the motor to the pump.

9. The method of claim 1 wherein providing energy to a motor comprises providing battery power to the motor.

10. The method of claim 1 wherein the time period is a function of the battery voltage and a function of the time from the start point to the end point.

11. A method for stopping a pump at the end of its motion comprising:

energizing a motor;

sensing a parameter indicative of a main current draw of the motor;

measuring the length of time from about a beginning of the main current draw to about the end of the main current draw;

allowing the motor to be energized for an additional time period that is a function of the time of main current draw; and

de-energizing the motor.

12. A method of controlling a motor for driving a pump comprising:

providing energy to a motor;

sensing a parameter indicative of current of the motor;

identifying a start point of a main current draw of the motor;

identifying an end point of the main current draw of the motor;

continuing to provide energy to the motor for a time period that is a function of the time from the start point of the main current draw to the end point of the main current draw; and

de-energizing the motor.

13. The method of claim 12 wherein the parameter indicative of current is a function of the voltage.

14. The method of claim 12 wherein the end point is at about the beginning of leveling off of current.

15. The method of claim 12 wherein the time period is about one-half of the time from the start point to the end point.

16. The method of claim 12 wherein providing energy to a motor comprises providing battery power to the motor.

17. The method of claim 12 wherein the time period is a function of the battery voltage and a function of the time from the start point to the end point.

18. A method for controlling a pump at the end of a motion comprising:

energizing a motor;

sensing a parameter indicative of a main current draw of the motor;

identifying a length of time from about a beginning of the main current draw to about an end of the main current draw;

energizing the motor for an additional time period that is a function of the time of main current draw; and

de-energizing the motor.

19. The method of claim 18 wherein the parameter indicative of current is a function of the voltage.

20. The method of claim 18 wherein the start point is at about the beginning of an increase in current.

21. The method of claim 18 wherein the end point is at about the beginning of leveling off of current.

22. The method of claim 18 wherein the time period is about one-half of the time from the start point to the end point.