EPICYCLIC GEAR TRAIN

PRESENTED BY—

AMIT PANDEY.

ANIL TYAGI.

GEAR TRAIN• A GEAR TRAIN IS A COMBINATION OF

GEARS USED TO TRANSMIT POWER FROM ONE SHAFT TO ANOTHER.

• THE MAIN OBJECTIVE TO BUILD A GEAR TRAIN IS TO CREATE LARGER GEAR RATIO IN A GEAR TRAIN.

TYPES OF GEAR TRAIN

• SIMPLE GEAR TRAIN

• COMPOUND GEAR TRAIN

• REVERTED GEAR TRAIN

• EPICYCLIC GEAR TRAIN

• IN SIMPLE GEAR TRAIN , EACH SHAFT SUPPORT ONE GEAR.

• IN A COMPOUND GEAR TRAIN, EACH SHAFT SUPPORTS TWO GEAR WHEELS EXCEPT THE FIRST AND THE LAST.

• IN A REVERTED GEAR TRAIN, THE DRIVING AND THE DRIVEN GEARS ARE COAXIAL OR COINCIDENT.

• IN A EPICYCLIC GEAR TRAIN, THE AXES OF SOME OF THE WHEELS ARE NOT FIXED BUT ROTATE AROUND THE AXES OF OTHER WHEELS WITH WHICH THEY MESH.

EPICYCLIC GEAR TRAIN

A Gear train having a relative motion of axes is called a planetary or an epicyclic gear train.

These are 2 degree of freedom devices. Means 2 inputs are needed to obtain a predictable output.

Epicyclic gear arrangement

ANALYSIS OF EPICYCLIC GEAR TRAIN

• Turn gear 2 through “x” revolutions in the clockwise direction. Assuming it’s motion as positive. And arm is fixed.

• Revolution made by arm = 0• Revolution made by gear 2 = x• Revolution made by gear 1 =

-(T2/T1)x• After this the mechanism is locked.

Thus the relative motion between gear 2 , 1 and arm will not alter.

• If the locked system be turned through ‘y’ revolutions in the clockwise direction. Then

• Revolutions made by arm = y• Revolutions made by gear 2 =

y+x • Revolutions made by gear 1 = y-

(T2/T1)x

TABULAR REPRESENTATION

S.NO. ACTION REV. OF ARM

REV. GEAR 2

REV. OF GEAR. 1

1 ARM FIXED ,X Rev. of GEAR 2

0 X -(T2/T1)X

2 LOCKED SYSTEMADD Y Rev.

Y Y + X y-(T2/T1)x

OBSERVATION

EXPERIMENTAL VALUES.

S.NO. REV. OF ARM

REV. GEAR 2

REV. OF GEAR. 1

1 75 39 0

2 12 0 12