GEARS AND GEAR DRIVES – COURSE QUESTIONS
1. With the help of the enclosed PDF, elaborate in about 15-20 lines, the ‘mechanical’ reasons for catastrophic structural failure of Aloha Flight 243.
2. You are to select a suitable drive for power transmission for an industrial equipment. As a design engineer, you select a belt-drive system over gear drive or a chain and sprocket drive. Justify your selection of a belt drive. (Parameters: Cost, Speed, Maintenance, Flexibility, Distance between driving and driven shaft, Noise and Vibration).
3. What is the RPM and rotational direction (Clockwise/Anticlockwise) of Gear D?
4. What is the RPM of Gear C?
5. Explain, with sketches, a speed reduction of 4.5:1 using (a) Simple gear train and (b) Compound gear train. Number of teeth on driving pinion in each gear train = 20 (Assume number of teeth for other gears).
6. Explain, with the help of a sketch, the Basic Law of Gearing.
7. Explain, with help of a sketch, the following gear tooth nomenclature: Addendum, Dedundum, Face width, Tooth thickness, Pitch Circle.
8. Explain, with a sketch, the working of Worm and Worm gears. In what kind of applications are worm gears preferred over traditional gear trains?
9. Why do you think a 5-speed manual Ford Mustang is geared as followed?
10. Given input rotational speed of 2000 rpm for Gear A in Clock-wise direction, find rotational speed and direction (clock-wise/anti-clock wise) for Gears B, C, D and E respectively. What is the ratio of (Power Output/ Power Input) and (Torque Output / Torque Input)?
11. Compare and contrast Spur and Helical gears with the help of sketch, based on their geometry and suitability of application.
12. Explain, with a labelled sketch, working of an automotive Serpentine Belt and its various elements.
