Transcript Gears & Spline Shafts Sharif Ali • What are they?

Gears & Spline Shafts
Sharif Ali
• What are they?
• What are they used for?
Gears
A Brief History
• Began as wood with pegs and
used animal fat grease as
lubrication
• Used in wind and water wheel
machinery and to power textile
machinery
Gears
Uses
 Three main uses:
• To change the rate of rotation
of a machinery shaft
•To change the direction of the
axis of rotation
•To change between rotary and
linear motion
Gears
Example 1
Spur Gears
Rate of Rotation
• Most common type of gear
• Straight teeth, parallel shafts
• Can be used to create large
gear reductions
• Used in oscillating sprinkler,
wind up alarm clock, washing
machine and clothes dryer
• Loud due to teeth collision
Spur gears
Gears
Example 2
Helical Gears
• Much more quiet and smooth
than spur gears due to the
angled cut of the teeth
• Can be mounted on
perpendicular shafts to adjust
angle of rotation by 90o
• Used in most car transmissions
Helical Gears
Gears
Example 3
Worm Gears
• Used when large gear
reductions are needed
• Worm can turn gear but gear
cannot turn worm
• Useful in conveyor systems
Gears
Example 4
Rack & Pinion Gears
Rotation into Linear
• Used in the steering system on
automobiles
• Also used on same scales
Spline Shafts
• Grooves or tongues are
machined along the length of
the shaft
• This allows for both the shaft
and another corresponding
shaft or component to rotate
together
References
• www.bergen.org
• www.howstuffworks.com
• www.efunda.com