How Do Petrol Pump Nozzles Know When to Turn Themselves Off?

🔧Petrol pump nozzles use the Venturi effect, which creates low pressure in the nozzle to turn off the flow of petrol when the tank is full.

💡A membrane is attached to a rod inside the nozzle, and when the petrol reaches a certain level, it moves the membrane, causing the nozzle to turn off.

🔬The Venturi effect happens when the air in the constricted part of the nozzle flows faster than the air in the wider part of the nozzle.

🔁When the petrol reaches the end of the Venturi tube, a membrane in the nozzle gets sucked into a chamber, closing the valve and turning off the flow.

🌡️The pressure in the nozzle decreases as the petrol level rises, causing the nozzle to turn off and prevent overflow and fire hazards.

How do petrol pump nozzles know when to turn off?

—Petrol pump nozzles use a combination of the Venturi effect, which creates low pressure in the nozzle, and a membrane that moves when the petrol reaches a certain level. These mechanisms work together to automatically turn off the flow of petrol when the tank is full.

How does the Venturi effect work in petrol pump nozzles?

—The Venturi effect happens when the air in the constricted part of the nozzle flows faster than the air in the wider part of the nozzle. This creates low pressure in the nozzle, which turns off the flow of petrol when the tank is full.

What is the purpose of the membrane in petrol pump nozzles?

—The membrane is attached to a rod inside the nozzle, and when the petrol reaches a certain level, it moves the membrane, causing the nozzle to turn off. The membrane helps ensure that the nozzle only dispenses petrol when needed.

Why is it important for petrol pump nozzles to turn off automatically?

—The automatic shut-off feature of petrol pump nozzles prevents overflow and spillage, which can be dangerous and wasteful. It also ensures that customers only pay for the fuel they actually need.

Are all petrol pump nozzles the same?

—While the basic principles of how petrol pump nozzles work are similar, there may be variations in design and specific mechanisms used. However, the goal of all petrol pump nozzles is to ensure safe and efficient fuel dispensing.

00:00In this video, the host investigates how petrol pump nozzles know when to turn themselves off.

02:55There are two main mechanisms in petrol pump nozzles that allow them to automatically shut off.

06:21The Venturi effect is one mechanism used in petrol pump nozzles to create low pressure and turn off the flow of petrol when the tank is full.

08:52A membrane inside the nozzle moves when the petrol reaches a certain level, closing the valve and turning off the flow.

10:38When the petrol level reaches the end of the Venturi tube, a membrane in the nozzle gets sucked into a chamber, closing the valve and turning off the flow.