Gears in every day life!
Gears are used in many machines. Many are machines we use in our everyday life, such as cars; wind up toys, clocks, mixers, bikes, oil rigs, vacuum etc. Gears make our lives easier in many ways. They allow us to change direction and speed of movement, measure time and create a great force “mechanical output” with a little force input.
The following will describe how gears are used in everyday machines.
Cars
A car has at least a first, second, third and fourth gear. These are the different sized gears that fit together in the car. The engine turns a set of gears that are joined to a rod called the crankshaft. The crankshaft turns the axel and then the axel turns the wheels and that moves the car. The first gear (lowest gear) allows the crankshaft to move faster than the wheels. It makes more power for starting out and going up hills. The fourth gear highest gear) makes the wheels travel around quicker with less power. The fourth gear is used to drive on the highway.
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This is a picture of the crank shaft!
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Clocks
Many clocks and watches today are electronic but, gears have been used for a long time to run mechanical clocks like pendulum and mainspring clocks.
Pendulum Clock
A pendulum clock works by having a heavy weight that hangs on a cord or a chain the cord is attached to a drum, which is connected to a series of gears. Each gear has a different amount of cogs and goes at a different, but steady, speed. The gears move the hands on a clock. It all happens when the clock is wound, the cord wraps around the drum, pulling the weight up. When the weight starts to fall, the cord unwinds and turns the drum. This sets the gears moving, each one at its own set speed, and these turn the hands of the clock.
Pendulum
Clock Work
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Spring Driven Clock
A spring driven clock has a winding device. A mainspring winds tighter inside as it unwinds it moves gears that are controlled by an escapement that controls the movement of the hands. Toys often use spring driven mechanisms.
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On the next page you will see some pictures of gears.
