An epicyclic gear train consists of three wheels A, B and C as shown in gig. 1 Wheel A has 72 Internal teeth, C has 32 external teeth. The wheel B gears with A and C is carried on an arm which rotates about the Center of A at 18 rpm. If the wheel A is fixed, determine the speed of wheels B and C.

Mumbai University > Mechanical Engineering > Sem 5 > Theory of Machines-II

Marks: 10 Marks

Year: May 2016

$\because TA=74 \\ Tc=32 \\ NF =18 rpm \\ NA=0$

It is given that NF=y=25 rpm

$NA=y-xZc/ZA \\ 0=25-x*34/74 \\ X=54.411 rpm$

Also, speed gear ‘c’

Nc=x +y=54.411+25

Nc=70.411 rpm same direction of arm

$r_a= r_c+ D_B \\ D_a=D_c+2D_B \\ Z_A=Z_c+2Z_B \\ 74=34+2*Z_B \\ Z_B=20 \\ N_B=y-x*Z_c/Z_B \\ =25-54.411*34/20=-67.498 rpm$

NB=67.498 in opposite direction of arm.