The function of the automobile sensor is to detect the engine operating condition information related to the ignition advance Angle, and input the information to the electronic control unit as the basis for calculation and control of the ignition time. According to the physical quantity classification of the sensor, it can be divided into displacement, force, speed, temperature, flow, gas components and other sensors, such as air flow sensor, air intake temperature sensor, throttle position sensor, water temperature sensor, camshaft position sensor, crankshaft position sensor, knock sensor, oxygen sensor, etc. Here are five types of sensors commonly used in cars:
1. Air flow sensor
The air flow sensor converts the inhaled air into an electrical signal and sends it to the electronic control unit (ECU) as one of the basic signals to determine the injection of oil. Depending on the measurement principle, Can be divided into rotary vane type air flow sensor (Toyota PREVIA station wagon), Carmen vortex type air flow sensor (Toyota Lexus LS400 car), hot wire type air flow sensor (Nissan Qianli carriage with VG30E engine and domestic Tianjin Sanfeng bus TJ6481AQ4 installed with Volvo B230F engine) and hot film type air There are four types of gas flow sensors. The first two are volume flow type and the last two are mass flow type. At present, two kinds of hot wire air flow sensor and hot film air flow sensor are mainly used.
2. Intake pressure sensor
The intake pressure sensor can measure the absolute pressure in the intake manifold according to the load state of the engine, and is converted into electrical signal and speed signal together into the computer, as the basis for deciding the basic injection amount of fuel injector. Domestic Audi 100 sedan (V6 engine), Santana 2000 sedan, Beijing Cherokee (25L engine), Toyota Crown 3.0 sedan, etc., all use this pressure sensor. At present, semiconductor varistor type intake pressure sensor is widely used.
3. Throttle position sensor
The throttle position sensor is installed on the throttle to detect the opening of the throttle. It is connected with the throttle valve through the lever mechanism to reflect the different engine conditions. This sensor can detect different engine conditions and input the electronic control unit (ECU), so as to control different fuel injection volume. It has three types: switch contact type throttle position sensor (Santana 2000 sedan and Tianjin Sanfeng bus), linear variable resistance type throttle position sensor (Beijing Cherokee), integrated throttle position sensor (domestic Audi 100 V6 engine).
4. Crankshaft position sensor
Also known as the crankshaft Angle sensor, is the most important sensor in the computer-controlled ignition system, its role is to detect the top dead center signal, crankshaft Angle signal and engine speed signal, and input it into the computer, so that the computer can issue the best ignition time instruction according to the cylinder ignition sequence. There are three types of crankshaft position sensors: electromagnetic pulse type crankshaft position sensor, Hall effect type crankshaft position sensor (Santana 2000 sedan and Beijing Cherokee), photoelectric effect type crankshaft position sensor. The control mode and precision of crankshaft position sensor are different. Crankshaft position sensors are generally installed on the side of the crankshaft pulley or sprocket, some are installed on the front of the camshaft, and some are installed on the distributor (Santana 2000 car).
5. Knock sensor
The knock sensor is installed on the cylinder block of the engine to monitor the knock condition of the engine at any time. At present, there are resonant type and non-resonant type. When it rains, the windshield wiper on the front of the car and car will act in a neat way, and the two wipers will swing to the fixed rotating shaft column as the center, scraping the rain off the front windshield and giving the driver an effective view. The earliest wipers consisted of a rocker arm and a squeegee arm that was manually operated by the driver. Later, in order to see the needs of the position, the wiper arm is installed on the left and right sides, connected with connecting rods, and becomes a manual double wiper, which is the original type of today's car wiper.
