MIME 3300 Homework 10 4/8/2010
Write your final answers below and submit this page with the rest of your
1. Find the diametral pith of a pair of gears whose center distance is
0.3625 in. The gears have 32 and 84 teeth respectively.
2. Determine the module of a pair of gears whose center distance is 58
mm. The gears have 18 and 40 teeth respectively.
3. What are the diametral pitch and the pitch diameter of a 40-tooth
gear whose circular pitch is 3.5 in?
4. A 4-diametral-pitch, 24 -tooth pinion is to drive a 36-tooth gear. The
gears are cut on the 200-full depth involute system. Find and
tabulate the addendum, dedendum, clearance, circular pitch, tooth
thickness, pitch diameters, gear ratio, base circle diameters and the
paths of approach and recess.
5. Answer the following questions:
a) The fundamental law of gearing states that the ratio of the number of
teeth of the pinion and the gear is equal to the ratio of their diameters.
b) The larger that diametral pitch of a gear the thicker its teeth are. (T-F)
c) The larger the module of a gear the thicker its teeth are. (T-F)
d) The line of action always passes through the pitch point. (T-F)
e) The addendum of a gear is typically smaller than its dedendum. (T-F)
f) The base diameter of a gear is larger than its pitch diameter. (T-F)
g) The velocity ratio is equal to the ratio of the distances of the centers of
the pinion and the gear, respectively from the line of action. (T-F)
h) The line of action is tangent to the pitch circles of the gear and the
i) The portion of the profiles of the teeth of the pinion and the mating gear
above the corresponding base circles are identical if the standards of the
American Gear Manufacturer's Association (AGMA) are followed. (T-F)
j) Look at a sketch showing the teeth of a pinion and gear. The pinion is
driving the gear. The point where the first contact between the pinion
and the gear teeth occurs is the intersection of the addendum circle of
the gear with the line of action. (T-F)