How does a hand soap pump work?

God makes it workHow does a hand soap pump work?
When the tube is pressed inside, a spring is now compressed.


This makes the tube come out automatically on releasing the pressure.





There is a valve mechanism on the top of the tube which allows fluids to come from inside to out side and not the other way.





While we press the tube inside, the air in the tube goes out and cannot re enter the tube ( even after the tube has returned to its normal position).





The pressure inside the tube is decreased and to compensate the fall in pressure, the air above the liquid soap presses the liquid through the tube outside.How does a hand soap pump work?
TRY PUSHING THE TOP





It comes out the little spout provided thus causing your soap to despece :S
there is a one way (slapper valve) and two cylinders one fitting over the other... when you push on it... the fluid has to go somewhere... because the valve closes... so it comes out the spout.
howstuffworks.com very good website, get smarts!
Pushing down creates pressure in the bottle. The only other way out for the soap is up the tube.