Cosmetic sprayer bottles may be one of the best examples of how we can apply principles found in nature into simple technology. The ingenious idea behind spray bottles is actually the same principle that enables our hearts to pump blood throughout the body. It is what we call a reciprocating pump mechanism.
In a reciprocating pump, two alternating actions are involved. The first action is used to collect liquid into a small chamber through one opening. The second action is to release the liquid through a second opening. This is how the heart collects oxygenated blood from the lungs into its chambers and then pumps it out to the rest of the body.
In a spray bottle, the two actions are done whenever you press the button (or actuator) and second, when the button rises once you release it. Releasing the actuator will allow the pump to suck liquid from inside the container to a small cylindrical chamber. The chamber is located in the neck area of the bottle. Pressing the actuator will then release the liquid from the chamber into the nozzle and out of the bottle.
The reciprocating pump is a relatively simple concept but serves excellently as a dispensing mechanism for spray bottles. It can also be found in many other applications, such as medical equipment, and aeronautics. It is also a fundamental principle used in extracting water and oil from underneath the earth.