Gears
A gear is a mechanical device that transmits rotary motion by changing the magnitude and line of action of the effort force.
The effort force can be expressed as
F = W (r1 r2.. r n ) / (R1 R2.. R n ) (1)
where
F = effort force (N, lbf )
W = load force or weight (N, lbf )
r = gear wheel inside diameter (m, in)
R = gear wheel outside diameter (m, in)
Example - Gear Transmission and Effort Force
The effort force in a gear transmission with three wheels:
- wheel 1 : r1 = 0.05, R1 = 0.12
- wheel 2 : r2= 0.06, R2= 0.13
- wheel 3 : r3 = 0.07, R3 = 0.14
and a weight load of 1000 N can be calculated as
F = W (r1 r2r n ) / (R1 R2R n )
= (1000 N) ((0.05 m) (0.06 m) (0.07 m)) / ((0.12 m) (0.13 m) (0.14 m))
= 96 N
= 0.1 kN
Related Topics
• Mechanics
The relationships between forces, acceleration, displacement, vectors, motion, momentum, energy of objects and more.
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