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1/8

+

+

L/2

L/2 L/2

WB

W W

R L/8

R R

L

2

A

F

C

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+

& into

( ) [ ]

[ ] [ ] [ ] [ ]

[ ]

F=weight of the coconut = 19.62N

WB=weight of the shaft = 30 9.81 = 294.3N

L = Length of the beam = 1m

WG1= weight of gear 1 = 19.81 = 9.81 N

WG2= weight of gear 2 = 19.81 = 9.81 N

1 2

3

4

2 3 4

5

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into

into

+

( ) ( ) [ ] [ ]

5 3

5 2

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( ) () ( ) () ( )(

) (

) (

)(

)

+

(

) (

)(

)( )

So choose the max valve of moment M=57.23 Nm

We calculated the total force acting on the shaft is

Assume the gear radius is 0.10 m

0.1m

F

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From table that Jaya found at the F is 30.84 9.81 = 302.54 N. So we assume F = 350 N

N m

( ) ( ) We set design factor, n = 2

Torque required to dehusk a coconut:-

From the ergonomic table from human force, we find that an average male (in free posture)

uses 68 pounds if force to push. Using this as the set point for force required to dehusk the

coconut we calculated the required torque :

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So we assume F = 350 N

For both dehuskers

For RPM,

70 Nm lb/ft

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The required RPM for the dehusker = 40 rpm.

The provided RPM for the electric motor = 500 rpm

(Lowest RPM is chosen to provide higher torque)

Diameter of the gear attached to the driving shaft = 0.2 m

N4 = 50rpm d4= 0.2 m

N3= N2= 150 rpm d2= 0.3 m

N1 = 500 rpm

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N1 N2

d1 d2

N2 N3

d3 d4

N3