TABLE OF CONTENTS 
Driver and driven gears rotate in opposite directions.
The relative speed of the gears is calculated by the expression:
Calculate the speed of the driven gear if the driving gear is rotating at 120 rev/min. The driven gear has 150 teeth and the driving gear has 50 teeth:
Driver and driven gears rotate in the same direction if there is an odd number of idler gears, and in the opposite direction if there is an even number of idler gears.
Idler gears are used to change the direction of rotation and/or to increase the centre distance between the driver and driven gears.
The number of idler gears and the number of teeth on the idler gears do not affect the overall relative speed.
The overall relative speed is again calculated using the expression:
Unlike the idler gear of a simple train, the intermediate gears of a compound train do influence the overall relative speeds of the driver and driven gears.
Both intermediate gears ( l 1 and l 2) are keyed to the same shaft and rotate at the same speed.
Driver and driven gears rotate in the same direction. To reverse the...
