Apparatus and method for controlling a driving motor

A method for controlling a driving motor whose driving power is transmitted to a driven device through a mechanism composed by at least two gears, said method comprising:

• the step of engaging a first gear with the driving motor;
• the step of engaging a second gear with the first gear with a backlash;
• the step of turning the driving motor at a predetermined first speed;
• the step of directing the slowing down the driving speed of the driven device;
• the step of changing a speed of the driving motor from the first speed to a slower second speed in response to the direction to slow down;
• the step of waiting for a predetermined period after the slowdown operation while maintaining the second speed;
• and
• the step of braking the driving motor rapidly after the step of waiting for a predetermined period.

A controlling apparatus of a driving motor comprising:

• a driving motor which turns at a predetermined speed;
• a first gear engaged with said driving motor;
• a second gear, engaged with said first gear with a backlash, for transmitting a driving power to a driven device;
• a directing device for directing the slowing down of the driving speed of the driven device;
• and
• a controller for slowing down the speed of said driving motor in response to the output of said directing device so that the rear of a cog of said second gear may leave the front of a cog of said first gear and for braking the driving motor rapidly after the front of another cog of said second gear reaches the rear of said cog of said first gear.