What does a brake servo do?

A brake servo, also known as a brake booster or power brake, is a device that assists the driver in applying force to the brake pedal, usually through either a hydraulic or vacuum-based mechanism. It multiplies the force exerted by the driver's foot on the brake pedal, making it easier to stop the vehicle.

Here are some additional details about how brake servos work:

1. Hydraulic Brake Servo (Power Brake):

- In a hydraulic brake servo, a hydraulic pump driven by the engine creates hydraulic pressure.

- When the driver presses the brake pedal, a valve opens allowing the hydraulic pressure to enter a chamber or diaphragm.

- The hydraulic pressure multiplies the force applied by the driver on the brake pedal, reducing the effort required.

2. Vacuum Brake Servo:

- In a vacuum brake servo, the engine creates a vacuum in a sealed chamber or chamber.

- When the driver presses the brake pedal, a valve opens allowing atmospheric air to enter the chamber, reducing the vacuum.

- The difference in pressure between the high vacuum and atmospheric pressure creates a force that boosts the force applied by the driver on the brake pedal.

Both hydraulic and vacuum brake servos make braking more efficient and less strenuous for the driver, particularly in heavy vehicles where greater force is required to stop.