For simple and cheap dispensers of children's candy, Pez machines are surprisingly complex in their construction. While other small candies sold in stack format require a certain amount of wrapper-ripping and rooting around for the last few, Pez machines are designed to move each candy into a convenient place to be easily grabbed and eaten. This requires a device consisting of a hollow shaft, two springs, a plastic inner shelf, and a small lever.
Raising the Candies
When Pez candy tablets are removed in stacks from their wrappers and placed into a dispenser, they are loaded onto a shelf inside a rectangular tube. This shelf is loaded with a small spring beneath it, causing it to rise to the top of the dispenser unless it is pushed down. Pez candies are specially made to be hard enough to withstand this pressure and still keep their shape, so when they're loaded into the dispenser, they push the shelf down. This means that every time a candy is removed, the stack of candies left behind rises up to fill in the vacated space. Each candy, right down to the very last, will rise up to the top of the dispenser before it is removed.
The shelf is attached to runners (grooves) inside the hollow shaft. These grooves stop at the top and hold the shelf in place, which in turn holds the spring in place. Because of this, even when the dispenser is empty, the shelf and spring will stay in place.
Though Pez dispensers come with a wide variety of colorful heads shaped like favorite fictional characters, they all work with the same mechanisms. The head operates as a lid and is only attached to the shaft of the dispenser by a hinge at the back. This hinge has its own spring, which holds the head in the closed position, unless someone is pulling it back. Since the Pez machine is designed to be gripped in the palm of the hand and opened with the thumb, this spring is not too strong to be comfortably and repeatedly pulled against using only finger strength.
As the top of the head is pulled back, its bottom edge pushes forward. On the lower inside of the head, there is a small plastic protuberance which is designed to line up with the back edge of the newly-raised top candy. As this tiny "foot" comes forward, it presses the top candy forward, making it stick out, easy to grab.