This is a example of a piston engine. Piston engines use pistons and valves to rotate a shaft. They work by opening a valve to pull a piston upward using the low pressure form the vacuum cleaner. These engines are more complicated than turbine engines because of timing and moving components. to get a piston engine to work you must time the valve to open when you piston is in the furthest down position allowing it to be pulled up then close the valve to let the piston move back down.