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For printer friendly versions of the experiments, go to:
www.knex.com/instructions
and enter the code
79318.
8
Objectives:
Understand and describe
the transfer of motion through a
spur gear system and investigate the
relationship between gear size, speed
of rotation and force.
Materials You Will Need:
PROCESS:
1. Build the CRANK FAN model by following the step-by-
step building instructions.
2. Explore your model. Locate and identify the gears.
Watch the gear mechanism in operation as you turn
the crank.
79318
built CRANK FAN model
masking tape
paper or notebook
driver gear
fan blades
crank
driven gear
3. Using your notebook, explain how the gear system
turns the fan blades. How do the fan’s gears fit
together? Are they in line with each other?
4. This arrangement is called a Spur
Gear System. In this arrangement,
the gears fit together, or mesh,
along the same line or in the same
plane. In the Crank Fan, the gears
are arranged one above the other.
Turn your model on its side so you
can see how the gears are in line with each other.
5. The names of the various
parts of this model are:
Crank, driver gear, driven
gear, and fan blades. Using
masking tape, label the
different parts of your
model.
6. Using your notebook,
respond to the following:
(a) Describe how the moving parts that you labeled
above are connected to each other.
Experiment #1
Using a Spur Gear
System in a Crank Fan
(EN)
English
