What is the working principle of an engine vacuum system?
2 Answers
The working principle of an engine vacuum system is that the vacuum pump generates vacuum for the brake booster and for controlling the exhaust gas bypass valve. The recirculation air pressure relief valve also obtains vacuum through an electric switching valve (EUV). The vacuum pump mainly consists of components such as the pump body, rotor, vanes, and intake and exhaust ports. It refers to a device or equipment that uses mechanical, physical, chemical, or physicochemical methods to evacuate a container and achieve a vacuum. Functions of the engine vacuum pump: The function of the vacuum pump is to create negative pressure, thereby increasing braking force. The vacuum pump in a car generator is generally an oil pump, meaning the vacuum pump core rotates together with the generator shaft. By continuously sucking and pumping oil, negative pressure, or a vacuum, is created inside the vacuum pump housing. A vacuum pump is a device that improves, generates, and maintains a vacuum in a sealed space using various methods. Based on their working principles, vacuum pumps can be broadly classified into two types: gas capture pumps and gas transfer pumps. They are widely used in industries such as metallurgy, chemicals, food, and electronic coating.
I find the working principle of the engine vacuum system quite fascinating. Simply put, when the engine is running, the piston moves downward to draw in air through the intake manifold, where the pressure is lower than the outside atmospheric pressure, creating a state of negative pressure, which we call vacuum. This vacuum force isn't just for show—it powers many small devices, such as the brake booster, making it easier and less strenuous to apply the brakes. It also aids emission systems like the PCV valve, helping to recirculate oil vapors inside the engine, reducing pollution and waste. While studying cars, I realized why vacuum leaks can cause major issues—if the hoses age and develop leaks, the engine may idle roughly, or you might even notice harder brakes and reduced power. Older cars, in particular, need extra attention in this regard, with regular checks to ensure hose connections are secure to avoid safety hazards. Whenever I drive, I always keep an eye out for any signs of trouble in this area.
