As the name indicates it is the train of gears. When more than one gear is arranged together for transmitting torque or power from one system to another system then the arrangement is called a gear train. The size of the gear trains can be very small (in a wristwatch) to very large (in an industrial gear box). The arrangement of the gear train depends upon the amount of torque to be transmitted, the orientation of the input and the output shafts, and the size of the gear box.
A gear train is a set or system of gears arranged to transfer rotational torque from one part of a mechanical system to another.
Gear trains may consist of:
>> Driving gears – attached to the input shaft
>> Driven gears/Motor gears – attached to the output shaft
>> Idler gears – interposed between the driving and driven gear in order to maintain the direction of the output shaft the same as the input shaft or to increase the distance between the drive and driven gears.
Applications of Gear Trains
Gear trains are used in representing the phases of moon on a watch or clock dial. It is also used for driving a conventional two-disk lunar phase display off the day-of-the-week shaft of the calendar.
Types of Gear Trains :