reverted gear trains

today we will discuss about the reverted gear trains :-
when the axes of the first gear and the last gear are co-axial then the gear train is known as the reverted gear train..
we see that gear 1 drives the gear 2 in the opposite direction ..since the gear 2 and the 3 are mounted on the same shaft ,therefore they form a compound gear and the gear 3 will rotate in the same direction as that of gear 2...the gear 3 drives the gear 4 in the same direction as that of gear 1..thus we see that in a reverted gear train,the motion of the first gear and the last gear is like...

compound gear train

now we will deal with the compound gear train:-
 when there are more than one gear on a shaft it is called compound train of gears...
we have seen that the idle gears,in a simple train of gears do not effect the speed ratio of the system.but these gears are useful in bringing over the space between the driver and the driven.....

but whenever the distance between the driver and the driven or followers has to be bridged over by intermediate gears and at the same time a great speed ratio is required ,then the advantage of intermediate gears is intensified by providing compound gears on intermediate shafts ..
in this case ,each intermediate shaft has two gears rigidly fixed to it so that they may have the same speed...one of these two gears meshes with the driver and the other with the driven or follower attached to the next shaft ...

simple gear train

now we will deal with the simple gear train.....
when there is only gear on each shaft it is known as the simple gear train..
the gear are represented by there pitch circle..
when the distance between the two shafts is small the two gears one and two are made to mesh with each other to transmit motion from one shaft to the other ...
since the gear one drives the gear two therefore gear one is called driver and the gear two is called the driven or follower...
it may be noted that the motion of the driven gear is opposite to the motion of driving gear..

types of gear trains

today we are going to discuss about the types of gear trains:--

following are the different types of gear trains,depending upon the arrangement of wheels:-

1.simple gear train
2.compound gear train
3.reverted gear train
4.epicyclic gear train


in the first three types of gear trains ,the axes of the shafts over which the gears are mounted are fixed relative to each other ...
but in case of epicyclic gear trains ,the axes of the shaft on which the gears are mounted may move relative to a fixed axis..

introduction to gear trains

today we will discuss about the gear train system......
sometimes two or more gears are made to mesh with each other to transmit power from one shaft to another ..
such a combination is called gear train or train of toothed wheels..
the nature of the train used depends upon the velocity ratio required and the relative position of the axes of shaft s.a gear train may consist of spur ,bevel or spiral gears...