The worm shaft shown in part a of the figure transmits 1.2 hp at 500 rev/min. A static force analysis gave the results shown in part b of the figure. Bearing A is to be an angular-contact ball bearing selected from Table 11-2, mounted to take the 555-lbf thrust load. The bearing at B is to take only the radial load, so an 02-series cylindrical roller bearing from Table 11-3 will be employed. Use an application factor of 1.2, a desired life of 30 kh, and a combined reliability goal of 0.99, assuming distribution data from manufacturer 2 in Table 11-6. Specify each bearing.
Problem 11-35,
(a) Worm and worm gear, (b) force analysis of worm shaft, forces in pounds.
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Shigley's Mechanical Engineering Design (McGraw-Hill Series in Mechanical Engineering)
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