A 500 pound weight is attached to a cable that is being lifted by a 10 inch diameter drum. The 48V DC motor selected has a no-load angular velocity of 800 RPM and a stall torque of 500 inch-pounds. A gearbox has been designed to spin the drum as quickly as possible. Assume that there are no friction losses in this system. The drum is driven by a 72-tooth gear with a diametral pitch of P=8, and is 3D printed such that it has a yield strength in shear of τy = 2500 psi. Assuming that the entire output torque required to turn the drum is produced by the force on one tooth, and that the gear tooth would fail by being sheared off at the pitch circle, determine the required gear face width, b, for a factor of safety of 3. Note that circular tooth thickness, t, at the pitch circle is π / (2P). Repeat for a gear made out of 6061 Aluminum (σy = 35 ksi, τy = 20 ksi).
A 500 pound weight is attached to a cable that is being lifted by a 10 inch diameter drum. The 48V DC motor selected has a no-load angular velocity of 800 RPM and a stall torque of 500 inch-pounds. A gearbox has been designed to spin the drum as quickly as possible. Assume that there are no friction losses in this system.
The drum is driven by a 72-tooth gear with a diametral pitch of P=8, and is 3D printed such that it has a yield strength in shear of τy = 2500 psi. Assuming that the entire output torque required to turn the drum is produced by the force on one tooth, and that the gear tooth would fail by being sheared off at the pitch circle, determine the required gear face width, b, for a factor of safety of 3. Note that circular tooth thickness, t, at the pitch circle is π / (2P).
Repeat for a gear made out of 6061 Aluminum (σy = 35 ksi, τy = 20
ksi).
Only do the part for the 6061 gear do not do it for the 3D printed gear
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