In epicyclic gear train ,the axis of at least one of the gears moves relative to the frame. A gear train having a relative motion of axes is called a planetary or an epicyclic gear train.

1. EPICYCLIC GEAR
TRAIN
VAIBHAV SANJAY PATIL
170101092035
Roll No. : - 14
Div. : - A

2. EPICYCLIC GEAR TRAIN
In epicyclic gear train ,the axis of at least one of the gears moves relative to the frame.
A gear train having a relative motion of axes is called a planetary or an epicyclic gear train.

3. The annulus ‘A’ in an epicyclic gear train rotates at 300rpm about
the axis of fixed sun gear which has 80 teeth. A 3 arm spider is
driven at 180rpm. Determine the number of teeth required on
planet ‘P’
Given : -
ts = 80
N6 = 180rpm
NA = 300
NS = 0
rs + 2 rp = ra

4. Ds + 2 Dp = Da
Since module is same it follows that,
ts + 2 tp = tA …………….(1)
Steps Operation Arm C Gear S Gear P Gear A
1. Fix the arm C and give
1 rotation to S
0 +1 -(tS/tP) -(tS/tP) x (tP/tA) - (tS/tA)
2. Multiply ‘m’ 0 m -m x (tS/tP) -m x (tS/tA)
3. Add n to all elements n n n n
4. Total motion n m + n -m x (tS/tP) + n -m x (tS/tA) + n

5. Since NC = 180rpm
therefore, n = 180
NS = 0
m + n = 0
∴ m = -180
∴ -m x (tS/tA) + n = 300
-(-180) x (80/tA) + 180 = 300
tA = 120
Put this value in equation (1)
∴ 80 + 2tP = 120
tP = 20

6. Thank You…