How does an Oscillating Fan Work?

That table top fan that you use is more interesting than you think!  I took mine apart to see how it works.  The "four speed mechanism" releases any other button that was previously pressed down. Once a button is pressed a signal (voltage) is sent to the motor at the top of the fan. The oscillation motion is produced through the 4 bar mechanism. 

The last part of the video covers the gears that turn the 4 bar mechanism. The pin is part of the gears - when it is lifted the gears don't connect and the fan will no longer oscillate back and forth.