Brake Booster: Making Brake Application Less Hard

The Mercedes-Benz brake system is composed of two brake assemblies: hydraulic and friction brakes. The friction brake assembly sits right smack on brake operation flash points, while the hydraulic brake parts are located adjacent to the enginewhere they are on high groundto provide supplemental braking and enhance the friction brakes.

On a Mercedes-Benz disc brake set, friction brakes consist of a rotor/disc and a pair of brake pads, while on a drum brake assembly a drum takes up the place of the disc and the brake shoes that of the brake pads. Friction brakes use the traditional clamp-style method: a piston fitted with brake shoes, or a caliper with brake pads, tightening on a rotor to retard the motion of the car.

Every time the caliper/piston grips the rotor, the rotational motion of the rotor turns into heat. Because of a potential heat buildup, friction brake parts are made of materials with high heat resistance. The brake pads, for example, are embedded with materialscommonly asbestoswhich make the pads last long in the face of chronic heat present in the Mercedes-Benz brake assembly. The brake discs, on the other hand, are fitted with heat vents. The brake disc contact surface comes in either slotted or cross-drilled design, a structural feature that exhausts heat away from the brake assembly.

Friction brake parts inevitably succumb to heat, with its brake pads thinning out and/or the disc getting deformed on account of the friction. Unavoidably, they need to be replaced. In the event that the friction brake parts lose the up-to-specs brake power, the Mercedes-Benz brake system borrows time from its hydraulic brake assembly.

Composed of a network of brake hoses, brake booster, and hydraulic pumps, hydraulic brakes supply brake fluid in the Mercedes-Benz brake system. With the brake system well oiled, brake operation becomes less hard on the friction brake parts. Central to the Mercedes-Benz hydraulic brakes is the brake booster, typically the black canister that sits snug under the car hood. The Mercedes-Benz brake booster consists chiefly of a vacuum booster, linked to the master cylinder piston and the brake pedal by a push rod. In the event that the friction brake parts thin out, brake operation is compromised. In most cases, it shows up in the form of deep pressing on the brake pedal. The Mercedes-Benz brake booster eases brake application by providing the necessary brake assist.

Inside the vacuum booster, a diaphragm partitions the canister between the low-pressure vacuum and the high-pressure ambient air. A hose from the engine opens to a clever valve and supplies the vacuum to the booster. When the brake pedal is pressed, the rod cracks the valve open, allows ambient air to get into the canister and push the vacuum side of the diaphragm, and thrusts the rod on to the master cylinder piston. The master cylinder piston then engages the Mercedes-Benz brake system to retard the motion of the car.