What separates atmospheric pressure from vacuum in the brake system?

In a brake system, the diaphragm is a critical component that differentiates atmospheric pressure from vacuum. The diaphragm creates a flexible barrier that separates the two sides of the brake booster. One side is exposed to atmospheric pressure, while the other side operates under vacuum conditions. This difference in pressure allows the brake booster to amplify the force applied to the brake pedal, providing more braking power with less effort from the driver.

When the driver presses the brake pedal, atmospheric pressure pushes against the diaphragm, while the vacuum on the other side enhances this force. The effectiveness of this system relies on the diaphragm maintaining a proper seal to ensure that the pressure difference is upheld, facilitating the necessary boost in braking force.

Other components such as the vacuum assist booster, return spring, and output rod serve different functions within the braking system, but it is the diaphragm that plays the key role in managing and maintaining the separation between atmospheric pressure and vacuum.