I. Automotive sensors
Automotive sensors are input devices for the automotive computer system, which convert various operating conditions of the vehicle, such as vehicle speed, temperature of various media, engine operating conditions, etc., into electrical signals for transmission to the computer so that the engine is in the best working condition.
 
Basic characteristics
 
A sensor is a device or a device that can sense a specified physical quantity and convert it into a usable input signal according to certain rules. In simple terms, a sensor is a device that converts a non-electric quantity into an electrical quantity. Sensors are usually composed of three parts: sensitive elements, conversion elements and measurement circuits.
 
(1), the sensitive element is the part that can directly feel (or respond) to the measured, that is, the measured through the sensitive element of the sensor into a non-electric or other quantity with a definite relationship to the measured.
 
(2), the conversion element will be the above non-electricity into electrical parameters.
 
(3), the role of the measurement circuit is to convert the electrical parameters input by the conversion element into voltage, current or frequency and other measurable power, in order to display, record, control and process the part.
 
Applications
 
1, gasoline indicator, is through the level sensor to achieve, this level sensor using the level of the liquid and then converted into a digital signal, can be easily read from the instrument
 
2, water temperature sensor, water temperature sensor is installed in the water tank through the temperature measurement node device, when the water temperature is too high or too low can also be alarm, can also be read directly from the display instrument.
 
3, car air conditioning, car air conditioning is installed in the car through the temperature sensor to control the temperature sensor has a temperature setting, when the temperature is too low, automatically start, when the temperature exceeds and automatically cool down
 
4, wiper sensor, wiper is through the sensor to sense the size of the rain, so as to control the frequency of the wiper, that is to say, the rain is large to scrape fast, the rain is small to scrape slow.
 
5, engine management system, using a variety of sensors, the engine intake of air, cooling water temperature, engine speed and acceleration and deceleration and other conditions into electrical signals, sent to the controller. EMS can not only precisely control the fuel supply to replace the traditional carburetor, but also control the ignition advance angle and idle air flow, etc., which greatly improves the performance of the engine.
 
6、Control system principle: Through the pedal sensor installed on the accelerator pedal, the pedal information is transmitted to the throttle control module in the electronic controller. The throttle control module calculates the opening degree of the throttle through certain processing procedures and drives a DC motor to complete the adjustment of the throttle intake passage area, so as to control the air intake volume and meet the air intake requirements of the engine under different working conditions.
 
7、Burst sensor function: detects the vibration of the engine block for the electronic controller to identify the engine burst conditions. Principle: the detonation sensor is a vibration acceleration sensor. It is mounted on the engine cylinder block, can be installed one or more. The sensitive element of the sensor is a piezoelectric crystal, engine shock, engine vibration through the sensor mass block to the crystal. Piezoelectric crystal due to the pressure generated by the vibration of the mass, the two poles in the surface to produce voltage, the vibration into a voltage signal output.
 
8、Idle speed regulator function: provide idle speed bypass air channel and influence the bypass air volume by changing the cross-sectional area of the channel to achieve closed-loop control of the engine speed at idle conditions.
 
9、Oxygen sensor function: determine the oxygen content in the engine exhaust to determine whether the gasoline and air are completely combusted. Based on this information, the electronic controller achieves closed-loop control with an excess air coefficient of λ = 1 to ensure that the three-way catalytic converter has maximum conversion efficiency for all three pollutants in the exhaust - HC, CO and NOX.