Advanced Machine Design Questions & Answers on “Terminology of Spur Gears”.
1. In cycloidal gears contact area is
a) Comparatively smaller
b) Comparatively larger
c) Can’t be determined
d) None of the listed
Answer: b
Clarification: Convex flank on one tooth meets with concave on the other thus increasing the contact area.
2. Involute gears have greater contact area as compared to cycloidal gears.
a) True
b) False
Answer: b
Clarification: There is mating of two convex surfaces and hence lesser contact area.
3. Cycloidal teeth consist of
a) Hypocycloid curve
b) Epicycloid gear
c) Both hypocycloid curve and epicycloid curve
d) None of the mentioned
Answer: c
Clarification: It consist of both and thus are hard to manufacture.
4. Pressure angle remains constant in case of involute profile.
a) True
b) False
Answer: a
Clarification: The common normal always passes through the pitch point and thus maintain the constant inclination.
5. Pressure angle is _____ in case of cycloidal teeth.
a) Constant
b) Variable
c) zero
d) None of the listed
Answer: b
Clarification: Cycloidal teeth consist of two profiles.
6. Velocity ratio is the ratio angular velocity of driving gear to that of driven gear.
a) True
b) False
Answer: a
Clarification: Velocity ratio is simply the angular velocities ratio.
7. Velocity ratio and transmission ratio are the same thing.
a) True
b) False
Answer: b
Clarification: Transmission ratio is measured between first and last gear.
8. Contact ratio is always
a) =1
b) >1
c) <1
d) Can’t be determined
Answer: b
Clarification: Some overlapping is essential for continuous transfer of power.
9. Product of diametric pitch and circular pitch is?
a) π
b) 1/π
c) None of the listed
d) 2
Answer: a
Clarification: CP=πd/z and circular pitch=z/d.
10. Diameteral pitch is 5, then calculate module of the gear.
a) 0.2
b) 0.4
c) 5
d) 10
Answer: a
Clarification: Module is the inverse of diameteral pitch.