M6.9 Flashcards
1
Q
What are gears used for?
A
- gain mechanical advantage
- change direction of movement
2
Q
What are spur gears?
A
- straight teeth parallel to shafts axis
- connect parallel shafts only
- simple to manufacture
- ## can be noisy
3
Q
Smaller gear in the spur gear is called?
A
- pinion
4
Q
Advantage of a helical gear?
A
- carry heavier loads at higher speeds and runs more smooth and quietly
5
Q
Example of where a bevel gear is used?
A
- main drive shaft of an aircraft engine
6
Q
Advantages of bevel gears?
A
- smoother
- quieter
- carry greater loads
- change direction
7
Q
Advantages of worm gears?
A
- quiet
- ## carry heavier loads
8
Q
What is gear backlash?
A
- describe clearance between gear teeth at the meshing point
- allows for lubrication and expansion (prevents overheating and tooth damage)
9
Q
What are belts?
A
- loop of flexible material used to mechanically link or drive two or more rotating shafts
10
Q
What are the 2 types of belts?
A
- friction drive belts (requires tension to maintain correct tension)
- positive drive belts (rely on engagement of teeth on belt grooves)
11
Q
Flat belts are not advisable for high outputs at speeds? (True or false)
A
True
12
Q
Advantages of v belts?
A
- low cost
- ease of installation
- wide range of sizes
