EGR system control method 1) Mechanical and Electronic Control l Mechanical EGR system Advantages: simple structure, low cost, easy implementation and implementation. Disadvantages: The system lacks flexibility. l Electronically controlled EGR system (gas-electric and magneto-electric) Dynamic response is good and control accuracy is high. 2) Open-loop control and closed-loop control l Open loop control Advantages: simple structure, easy control. Key: The precise control of the EGR rate depends on the precise preparation of the control MAP. l Closed-loop control Advantages: It can automatically adjust to the best EGR amount according to the working conditions of the engine. High precision, dynamic response. Disadvantages: The structure is complicated. Another type of exhaust gas recirculation system currently used is the pulsed exhaust gas recirculation system developed by Hino Motor Co., Ltd. During the intake of the diesel engine, the exhaust valve is slightly raised and some of the high pressure exhaust gas is returned to the cylinder. This effect of the exhaust valve is achieved by modifying the shape of the exhaust valve cam and microlifting the exhaust gas recirculation system. In a pulsed exhaust gas recirculation system, the exhaust gas is re-fed back into the cylinder, so the pressure of the exhaust gas should be high enough to reverse the gas flow. To achieve such a high pressure can only be achieved by optimizing the valve lift and timing so that the pressure wave of the exhaust gas can be used. In this exhaust gas recirculation system, the exhaust gas pressure "pulses" are effectively utilized. The purpose of the EGR sensor is to make the vehicle meet the exhaust emission standards of various countries in the world. The EGR sensor feeds back the exhaust gas flow information to the engine electronic control system. In addition to the above applications, the structure of the EGR sensor makes it suitable for use in pedal position detection and heating, ventilation, and air conditioning systems. An exhaust gas recirculation (EGR) system is used to reduce the amount of nitrogen oxide (NOX) emissions in the exhaust gas. Nitrogen and oxygen only react under high temperature and high pressure conditions. The temperature and pressure in the combustion chamber of the engine meet the above conditions, especially during forced acceleration. When the engine is running under load, the EGR valve opens, allowing a small amount of exhaust gas to enter the intake manifold and enter the combustion chamber along with the combustible mixture. At idle, the EGR valve closes and almost no exhaust gas is recycled to the engine. Automobile exhaust gas is a non-combustible gas (without fuel and oxidant) and does not participate in combustion in the combustion chamber. It reduces the combustion temperature and pressure by absorbing part of the heat generated by combustion to reduce the production of nitrogen oxides. The amount of exhaust gas entering the combustion chamber increases as the engine speed and load increase. The main components of the EGR system are the numerically-controlled EGR valve. The digital EGR valve is installed on the right exhaust manifold. Its role is to independently control the amount of exhaust gas recirculated to the engine, regardless of the degree of manifold vacuum. . The EGR valve controls the amount of exhaust gas flowing back from the exhaust manifold to the intake manifold through three incrementally-diametered metering orifices to create a combination of different flow rates. Each metering hole consists of a solenoid valve and a needle valve. When the solenoid valve is energized, the armature is attracted to the top by the magnet to open the metering hole. The rotary needle valve feature ensures good sealing when the EGR valve is closed. The opening and closing of the EGR valve is controlled by a car computer (PCM). When the car is idling or has not reached operating temperature, the EGR valve is closed and no exhaust gas enters the combustion chamber. When the engine enters the normal operating temperature and the speed is higher than a certain RPM, the vacuum pushes the EGR valve open, allowing part of the exhaust gas to enter the combustion chamber with the intake air. The EGR valve is normally opened under the following conditions: 1. The engine warms up. 2. The speed exceeds the idle speed. The ECM controls the EGR system based on the engine cooling water temperature sensor, the throttle position sensor, and the air flow sensor. Torque-Slotted Screw,Star Shaped Screw,Star Head Screw,Star Drive Screws Suzhou Chenran Precision Fasteners Co., Ltd. , https://www.chenranfastener.com