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A 16-tooth pinion drives the double-reduction spur-gear train in the figure. All gears have 25° pressure angles. The pinion rotates ccw at 1200 rev/min and transmits power to the gear train. The shaft has not yet been designed, but the free bodies have been generated. The shaft speeds are 1200 rev/min, 240 rev/min, and 80 rev/min. A bearing study is commencing with a 10-kh life and a gearbox bearing ensemble reliability of 0.99, assuming distribution data from manufacturer 2 in Table 11-6. An application factor of 1.2 is appropriate. For each shaft, specify a matched pair of 02-series cylindrical roller bearings from Table 11-3.
(a)
(b) Developed view
Problem 11–37
(a) Drive detail; (b) force analysis on shafts. Forces in pounds; linear dimensions in inches.
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Shigley's Mechanical Engineering Design (McGraw-Hill Series in Mechanical Engineering)
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