Several kinds of typical automobile sensor

With the constant progress of science and technology, the development of the society, cars will be indispensable tools for people's life. Automobile sensor is the prerequisite of normal driving car, can let the engine is in the best working condition. Vehicle speed, a variety of media, such as temperature, engine operating condition can be converted into electrical signal loss to the motor controller. In the past, automotive sensors simply applied to the engine, has now been extended to the turf, body and electrical system lamplight, including temperature, pressure, flow, position, gas concentration, velocity, brightness, dry humidity, distance etc. Car sensors.

a, temperature sensor,

temperature sensor cable winding resistance, thermal resistance and thermocouple resistance type three types, their characteristics and application occasions are different, in terms of accuracy, response characteristic and adapt to the temperature all have their own characteristics.

with water temperature sensor as an example, its interior is a semi-conductor thermistor, the lower the temperature, the greater the resistance, the smaller the vice resistance, installed on the engine cylinder or cylinder head water jacket, direct contact with water, and measured the temperature of the engine cooling water.

changes according to the measured engine electronic control unit (the temperature of cooling water, as a correction signal of fuel injection and ignition timing. Simple said is users can now understand automobile engine water temperature of the temperature of the state, stop or sports, or how long does the movement, etc.

2, pressure sensor

pressure sensor is mainly used for detection of cylinder pressure and atmospheric pressure, pressure rise ratio, pressure in the cylinder of turbine engine, oil pressure, etc. Cars with a capacitive pressure sensor is widely applied, piezo-resistive type, differential transformer type ( LVDT) Surface, elastic wave type ( 看到) 。 Capacitive pressure sensor is mainly used for detecting negative pressure, hydraulic, pneumatic, measuring range from 20 to 100 kpa, has high energy input, good dynamic response and good environmental adaptability; Piezoresistive pressure sensor are greatly influenced by temperature, need another set temperature compensation circuit, but suitable for mass production; An LVDT has bigger pressure sensor output, easy to digital output, but poor anti-interference; SAW type pressure sensor with small volume, light quality, low power consumption, high reliability, high sensitivity, high resolution, digital output etc, used for auto air suction valve pressure test, can work stably at high temperatures, is an ideal sensor.

3, the speed sensor

the traditional mechanical speed table, the inside connection a flexible shaft, soft shaft with a steel wire rope, flexible shaft one at the other end is connected to the transmission gears, the gear spins rotate steel wire rope, wire rope odometer cover circle a magnet rotates, shield ring with the pointer and through the balance spring put pointer at zero, magnet rotational speed changes the size of the magnetic field lines to speed, balance is broken, the pointer is driven.

in modern automobile industry, adopt more electronic tachometer, a pointer type and LCD digital display type, table with digital integrated circuit, it will be the ignition coil and the voltage pulse driving pointer or digital display after calculation.

another tachometer from generator to obtain pulse signals to the tachometer circuit after the display speed value, but because of affected by factors such as generator belt creep, not very accurate.