The working principle of an automobile brake system is to decelerate the vehicle by converting kinetic energy into thermal energy through friction, and its operation can be divided into five steps. First, when the driver presses the brake pedal, the lever principle amplifies the acting force, the pedal pushes the push rod of the vacuum booster, and the air pressure difference generated by the engine intake manifold further increases the thrust. Second, the piston of the master brake cylinder is pressed to transfer brake fluid to the wheel cylinders of each wheel through oil pipes, and the hydraulic system ensures uniform pressure distribution. Third, the wheel cylinder piston pushes the brake pads (for disc brakes) or brake shoes (for drum brakes) into close contact with rotating components-disc brakes clamp the brake disc with brake pads, while drum brakes rely on the expansion of brake shoes to rub against the brake drum. Fourth, electronic control systems such as ABS monitor wheel speed and automatically adjust braking force at the critical point of wheel lock-up to prevent loss of control. Throughout the process, the high-temperature resistance (boiling point not lower than 205°C) and low-temperature fluidity (freezing point not higher than -40°C) of the brake fluid are crucial, while regular checks of brake pad thickness, fluid condition, and system sealing are key to maintenance. High-performance models may adopt ventilated discs or ceramic composite materials to enhance heat dissipation and resistance to thermal fade.
