Demountable drive mechanism

1. A demountable drive mechanism for coupling to a drive shaft of an operating device, the drive mechanism being directly securable to the drive shaft to cause the drive shaft to rotate, the drive mechanism comprising a geared electric motor having an output for coupling to the drive shaft, the drive mechanism having a torque arm adapted to engage a reaction surface so that the electric motor can impart torque to the drive shaft, and control means to control operation of the electric motor, the electric motor having an operating current that is monitored in small time increments wherein a maximum allowable current is set as a percentage above the operating current being monitored so that should there be a significant and rapid increase in operating current the motor shuts down.

2. The demountable drive mechanism according to claim 1 wherein the torque arm is mounted on the drive mechanism parallel to the drive shaft.

3. The demountable drive mechanism according to claim 1 wherein the electric motor is powered by at least one battery.

4. The demountable drive mechanism according to claim 1 wherein solid state relays are interposed between an electric input of the electric motor and the electric motor, the solid state relays causing voltage of the electric motor to pulse and cap an operating current peak when the motor is first switched on.

5. The demountable drive mechanism according to claim 4 wherein the solid state relays comprise field effect transistors.

6. The demountable drive mechanism according to claim 1 wherein the electric motor includes an armature that is fed by direct current through a plurality of brushes, monitoring means to monitor the current passing through the brushes over a period of time, storing means to store the measured information, comparative means to compare this information with the known wear rate of electric motor brushes, and signaling means to provide a signal that indicates that the brushes have been subjected to a particular current for a particular period of time that equates to an indication of a worn brush.

7. The demountable drive mechanism according to claim 6 wherein the indication of a worn brush is through a light emitting diode that is illuminated when the brush is in its last 10% or preset portion of usable life.

8. The demountable drive mechanism of claim 7 wherein the light emitting diode flashes and the flash sequence is related to the usable life still available.

9. The demountable drive mechanism of claim 7 wherein a flashing mounted light emitting diode provides a visual indication of brush failure.

10. The demountable drive mechanism of claim 6 wherein the storing means is a microprocessor coupled to the motor to store data and to provide a visual indication of the stored data.

11. The demountable drive of claim 10 wherein the stored data of the microprocessor may be interrogated by linking a computer to the microprocessor.

12. The demountable drive mechanism of claim 6 wherein the electric motor has at least two alternative operational brushes, the motor including switching means to switch from one brush assembly to another should a brush become open circuit and fail.

13. A demountable drive mechanism for coupling to a drive shaft of an operating device, the drive mechanism being directly secured to the drive shaft to cause the drive shaft to rotate, the drive mechanism comprising a geared electric motor having an output for coupling to the drive shaft, the drive mechanism having a torque arm adapted to engage a reaction surface so that the electric motor can impart torque to the drive shaft, and control means to control operation of the electric motor, wherein solid state relays are interposed between an electric input of the electric motor and the electric motor, the solid state relays causing voltage of the electric motor to pulse and cap an operating current peak when the motor is first switched on.

14. The demountable drive mechanism according to claim 13 wherein the torque arm is mounted on the drive mechanism parallel to the drive shaft.

15. The demountable drive mechanism according to claim 13 wherein the electric motor is powered by at least one battery.

16. The demountable drive mechanism according to claim 13 wherein the electric motor has an operating current that is monitored in small time increments wherein a maximum allowable current is set as a percentage above the operating current being monitored so that should there be a significant rapid increase in operating current the motor shuts down.

17. The demountable drive mechanism according to claim 13 wherein the solid state relays comprise field effect transistors.

18. The demountable drive mechanism according to claim 13 wherein the electric motor includes an armature that is fed by direct current through a plurality of brushes, monitoring means to monitor the current passing through the brushes over a period of time, storing means to store the measured information, comparative means to compare this information with the known wear rate of electric motor brushes, and signaling means to provide a signal that indicates that the brushes have been subjected to a particular current for a particular period of time that equates to an indication of a worn brush.

19. The demountable drive mechanism according to claim 18 wherein the indication of a worn brush is through a light emitting diode that is illuminated when the brush is in its last 10% or preset portion of usable life.

20. The demountable drive mechanism of claim 19 wherein the light emitting diode flashes and the flash sequence is related to the usable life still available.

21. The demountable drive mechanism of claim 19 wherein a flashing mounted light emitting diode provides a visual indication of brush failure.

22. The demountable drive mechanism of claim 18 wherein the storing means is a microprocessor coupled to the motor to store data and to provide a visual indication of the stored data.

23. The demountable drive of claim 22 wherein the stored data of the microprocessor may be interrogated by linking a computer to the microprocessor.

24. The demountable drive mechanism of claim 18 wherein the electric motor has at least two alternative operational brushes, the motor including switching means to switch from one brush assembly to another should a brush become open circuit and fail.