Introduction to Gas Pumps

Gas pumps fill our vehicles' tanks with precision. Understanding this everyday occurrence requires a dive into their cleverly engineered automatic shut-off systems.

At the nozzle's tip, a mechanical valve controls fuel delivery. This valve responds to changes in air pressure, which are key to the shut-off mechanism.

Inside the nozzle, a Venturi tube creates a pressure difference which allows air to flow, leading to continuous fuel dispensing until the tank is near full.

As fuel reaches the tank's brim, it obstructs air flow in the Venturi tube. This causes the pressure to equalize, triggering the shut-off valve.

The equalized pressure activates the automatic shut-off valve. Instantly, fuel flow ceases, preventing overfilling and potential hazardous spills.

Modern pumps integrate electronic sensors for precise control and to ensure safety. They prevent static electricity buildup and detect other potential issues.

Contrary to popular belief, a gas pump doesn't measure the tank's content directly. Instead, it relies on the physics of pressure change to know when to stop.