How does a clock run?

Many clocks and watches today are run by electricity.  But the most common type of clock, the spring or wind-up clock, is powered by the gradual uncoiling of a steel spring, which moves a series of gears, or wheels. 

The movement turns the hands that point to the hours and minutes on the clock’s face.

When you wind a clock, you are coiling the mainspring.  The spring is mounted on a large gear wheel.

As soon as the spring is wound up tight, it begins to unwind.  As the spring unwinds it turns the gear wheel, which causes the other wheels and parts in the clock’s mechanism to move.

Two special wheels, called the escape wheel and the balance wheel, keep the spring from unwinding too fast and make the wheels turn at an even rate of speed.

As the wheels turn, the movement slowly turns the hands that point to the hours and minutes on the clock’s face.

Watches are really small clocks.  A watch may have as many as 160 different parts.–Dick Rogers