Gear Train Application (continued)

Step 1: Determine the torques in each shaft by passing sections in the shafts as

shown below. Let F be the force acting on the mating gear teeth.

Step 2: Construct a free body diagram of the shafts for sections 1 and 2 as shown below.

Step 3: Calculate Shaft Torques:

Now T₁ = R₁ F, so F = T₁ / R₁ = T_A / R₁ (Torque in Shaft 1 = T_A)

So T₂ = R₂ F = R_{2 (}T_A / R₁) = T_A(R₂/R₁) (Torque in Shaft 2 = T₂)

In general: angle of twist = φ = T L / J G

where T = torque in shaft, L = length of shaft, J = polar moment of inertia of shaft

and G = shearing modulus of elasticity

Click here to continue with this example.

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