Problem # 1
For the spur gearset with 4) = 20°, while avoiding interference, find:
(a) The smallest pinion tooth count that will run with itself.
(b) The smallest pinion tooth count at a ratio mG = 2.5 and the largest gear tooth count possible with this pinion.
(c) The smallest pinion that will run with a rack.
Problem # 2
Figure shows an electric motor driving a machine by means of three straight tooth spur gears having 16. 32. and 24 teeth. The gears have P = 8 and 4 = 20°. The idler shaft is supported by bearings A and B.
a) For the direction of motor rotation shown. determine the radial load carried by each bearing.
b) Determine the bearing loads for the opposite direction of motor rotation.
c) Explain briefly why the answers to parts a and b are different.