Concept explainers
(a)
The pitch diameter for gear 2.
The pitch diameter for gear 3.
The pitch diameter for gear 4.
The pitch diameter for gear 5.
(a)
Answer to Problem 36P
The pitch diameter for gear 2 is
The pitch diameter for gear 3 is
The pitch diameter for gear 4 is
The pitch diameter for gear 5 is
Explanation of Solution
Write the expression for the compound reverted gear train.
Here, the numbers of teeth on gear 3 is
Write the expression for the ratio of output speed to input speed.
Here, the ratio of output speed to input speed is
Write the expression for the ratio of output speed to input speed in terms of number of teeth.
Write the expression for the smallest number of teeth on pinion without interference.
Here, the number of teeth on pinion is
Write the expression for the number of teeth on gear 3.
Write the expression for the number of teeth on gear 5.
Substitute
Write the pitch diameter for gear 2.
Here, the pitch is
Write the pitch diameter for gear 4.
Write the pitch diameter for gear 3.
Write the pitch diameter for gear 5.
Conclusion:
Assume the output speed of the gear train is
Substitute
Substitute
Substitute
Substitute
Substitute
Substitute
Substitute
Therefore, the speed is greater than
Assume number of teeth on gear 3 and gear 5 is equal to 44 teeth.
Substitute
Therefore, the assumption is correct.
Substitute
Thus, the pitch diameter for gear 2 is
Substitute
Thus, the pitch diameter for gear 4 is
Substitute
Thus, the pitch diameter for gear 3 is
Substitute
Thus, the pitch diameter for gear 5 is
(b)
The pitch line velocity for gear 2.
The pitch line velocity for gear 3.
The pitch line velocity for gear 4.
The pitch line velocity for gear 5.
(b)
Answer to Problem 36P
The pitch line velocity for gear 2 is
The pitch line velocity for gear 3 is
The pitch line velocity for gear 4 is
The pitch line velocity for gear 5 is
Explanation of Solution
Write the pitch line velocity for gear 2.
Here, the rotational speed of gear 2 is
Write the pitch line velocity for gear 3.
Here, the rotational speed of gear 3 is
Write the pitch line velocity for gear 4.
Here, the rotational speed of gear 4 is
Write the pitch line velocity for gear 5.
Here, the rotational speed of gear 5 is
Write the rotational speed of gear 4.
Write the rotational speed of gear 5.
Conclusion:
Substitute
Thus, the pitch line velocity for gear 2 is
Substitute
Thus, the pitch line velocity for gear 3 is
Substitute
Substitute
Substitute
Thus, the pitch line velocity for gear 4 is
Substitute
Thus, the pitch line velocity for gear 5 is
(c)
The tangential force on gear 2.
The radial force on gear 2.
The total force on gear 2.
The tangential force on gear 3.
The radial force on gear 3.
The total force on gear 3.
The tangential force on gear 4.
The radial force on gear 4.
The total force on gear 4.
The tangential force on gear 5.
The radial force on gear 5.
The total force on gear 5.
(c)
Answer to Problem 36P
The tangential force on gear 2 is
The radial force on gear 2 is
The total force on gear 2 is
The tangential force on gear 3 is
The radial force on gear 3 is
The total force on gear 3 is
The tangential force on gear 4 is
The radial force on gear 4 is
The total force on gear 4 is
The tangential force on gear 5 is
The radial force on gear 5 is
The total force on gear 5 is
Explanation of Solution
Write the tangential load on the gear 2.
Here, the power in
Write the tangential load on the gear 3.
Write the tangential load on the gear 4.
Write the tangential load on the gear 5.
Write the radial load on gear 2.
Write the total load on gear 2.
Write the radial load on gear 3.
Write the total load on gear 3.
Write the radial load on gear 4.
Write the total load on gear 4.
Write the radial load on gear 5.
Write the total load on gear 5.
Conclusion:
Substitute
Thus, the tangential force on gear 2 is
Substitute
Thus, the tangential force on gear 3 is
Substitute
Thus, the tangential force on gear 4 is
Substitute
Thus, the tangential force on gear 5 is
Substitute
Thus, the radial force on gear 2 is
Substitute
Thus, the total force on gear 2 is
Substitute
Thus, the radial force on gear 3 is
Substitute
Thus, the total force on gear 3 is
Substitute
Thus, the radial force on gear 4 is
Substitute
Thus, the total force on gear 4 is
Substitute
Thus, the radial force on gear 5 is
Substitute
Thus, the total force on gear 5 is
(d)
The input torque.
(d)
Answer to Problem 36P
The input torque is
Explanation of Solution
Write the input torque.
Conclusion:
Substitute
Thus, the input torque is
(e)
The output torque.
(e)
Answer to Problem 36P
The output torque is
Explanation of Solution
Write the output torque.
Conclusion:
Substitute
Thus, the output torque is
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Chapter 13 Solutions
Shigley's Mechanical Engineering Design (McGraw-Hill Series in Mechanical Engineering)
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