How do air brake canisters work on a big rig truck?


How do air brake canisters work on a big rig truck?

In: 2

Not sure about big rigs, but on school busses the air is pressurized inside a container and used to keep giant heavy springs apart, when the pressure is released when the brakes are applied, the springs clamp down on the brake rotors slowing or stopping the bus. Air pressure comes from an air compressor run off the engine. Busses typically have between 70 and 100 psi in their pressure tanks, and most will not let you go into gear before that pressure is reached.

The brakes in a commercial vehicle with air brakes are always applied when there is no air pressure.

Building air pressure releases the brakes so the vehicle can move.

Pressing the brake pedal reduces the amount of air flowing through the brake system, allowing the brake pads to tighten the brake drum and slow the vehicle.

Imagine a teeter totter/seesaw. Under one end is a very big air bag/balloon, you are sitting on the that end. The other end fully in the air is the brake. When you are sitting there, the brake is fully engaged. As that balloon fills with air, you are raised up and the brake is released from being all the way up, or fully engaged.

Hopefully this helps to understand.