Describes several typical automotive sensors

As technology continues to progress , social development, people's lives car will also be an indispensable means of transport. Automotive Sensor is a prerequisite to ensure normal driving , allowing the engine in the best working condition. Vehicle speed , a variety of medium temperature, the engine operating conditions can be converted into electrical signals so lost car controller . In the past, used in automotive sensors on the engine alone , has now been extended to the site , and the lighting body electrical system , in particular including measuring temperature, pressure , flow , position, gas concentration , speed, light intensity , humidity , distance , etc. Crankshaft Position Sensor Replacement . A vehicle speed sensor traditional mechanical speedometer , which connect a flexible shaft , flexible shaft has a wire rope , the other end is connected to the transmission shaft one gear , the gear driven rotary rotating wire rope , wire rope driven odometer a magnet rotating circle cover , the cover and the coupling ring and the pointer set to zero by the pointer position hairspring , rotational speed of the magnet causes changes in the size of the magnetic field lines , the balance is broken , the pointer is therefore driven . In modern automotive field , using more electronic tachometer , with pointer and LCD digital display , the table has a digital integrated circuit , it will convey the ignition coil voltage pulse has been calculated over the rear drive or digital display pointer moves . Another tachometer pulse signal is obtained from the generator to the tachometer speed value is displayed after the circuit , but due to the alternator belt slippage and other factors , the value is not accurate . Second, the pressure sensor is a pressure sensor are used to detect the cylinder vacuum, atmospheric pressure , the boost ratio of the turbine engine , the cylinder pressure , oil pressure . Automotive pressure sensor applications have more capacitive, piezoresistive , differential transformer (LVDT), surface acoustic wave type (SAW). Capacitive Crankshaft Position Sensor are used to detect negative pressure , hydraulic , pneumatic , measuring range 20 ~ 100kPa, with input high energy, dynamic response characteristics, environmental adaptability and other characteristics ; piezoresistive pressure sensor affected by temperature , the need separate temperature compensation circuit , but adapted for mass production ; LVDT Camshaft Positioning Sensor have a greater output , easy digital output, but poor immunity ; SAW pressure sensor with a small size , light weight , low power consumption , high reliability, high sensitivity , high resolution, digital output , etc. , for automotive suction valve pressure detection can work stably at high temperature , is an ideal sensor . Third, the temperature sensor wirewound resistive temperature sensor , thermistor and thermocouple resistance of three types , their characteristics and applications has the distinction , in terms of accuracy , response characteristics and adapt to temperature and other aspects of its own characteristics. The water temperature sensor, for example , its internal thermistor is a semiconductor , the lower the temperature , the greater the resistance , whereas the smaller resistance , mounted on the engine block or cylinder head of water put , in direct contact with the cooling water , which measured have the engine cooling water temperature. Electronic control unit according to this change of the measured temperature of the engine cooling water , fuel injection and ignition timing as the correction signal . Simply means that users can understand the car engine water temperature is now running the state , stop, or sports, or sports for how long .