First, the past and future of automobile air conditioning
Automobile air conditioning refers to a device that regulates the air quality in automobile seats. No matter how the weather outside the car changes, it can keep the humidity, temperature, flow and cleanliness inside the car within the comfort range of the driver.
Second, the characteristics of automobile air conditioning
As we all know, automobile air conditioner adjusts the air environment in the compartment at the expense of engine power. Understanding the characteristics of automobile air conditioning is beneficial to the use and maintenance of automobile air conditioning.
The automobile air conditioner is installed on the running vehicle and bears severe and frequent vibration and impact. Therefore, all components should have sufficient strength and vibration resistance, and the joints should be firm and leak-proof.
2. The power required for automobile air conditioning comes from the engine. Among them, cars, light vehicles, small and medium-sized passenger cars and construction machinery, the power needed for air conditioning and the power to drive cars all come from one engine.
3. The specific working environment of automobile air conditioner requires that the refrigeration and heating energy of automobile air conditioner should be as large as possible.
1) In summer, the passenger density in the car is high, the heat output is high, and the heat load is high; In winter, the human body needs a lot of heat for heating.
(2) In order to reduce self-weight, the automobile thermal insulation layer is generally very thin, with many doors and windows and a large area, so the automobile thermal insulation is poor and the heat loss is large.
(3) The working environment of the car is in the wild and directly affected by sunshine, frost, snow, wind and rain, and the environment changes dramatically.
Third, the performance evaluation index of automobile air conditioning
1. temperature index
The temperature index refers to the most important link.
2. Humidity index
The index of humidity is expressed by relative humidity. Because the relative humidity that people feel most comfortable is 50%-70%, the humidity parameters of automobile air conditioners should be controlled within this range.
3. Air freshness
Due to the narrow space and high occupant density, it is easy to produce hypoxia and high carbon dioxide concentration in a closed space.
4. Defrosting function
Because sometimes the temperature difference between the inside and outside of the car is very large, fog and frost will appear on the glass, which will affect the driver's sight, so the car air conditioner must have defrosting function.
5. Simple, easy and stable operation.
Automobile air conditioning must not increase the driver's labor intensity and affect the driver's normal driving.
Composition and principle of automobile air conditioner
First, the refrigeration principle of automobile air conditioning
When the compressor is running, the low-temperature and low-pressure refrigerant vapor generated in the evaporator is sucked and compressed, and then discharged at high temperature and high pressure (about 70℃, 147 1KPa).
Second, the main functions of automobile air conditioning
Principle of refrigeration system
Third, the composition of automobile air conditioning
The general automobile air conditioner is mainly composed of compressor, electromagnetic clutch, condenser, evaporator, expansion valve, liquid storage dryer, pipeline and condensing fan.
Four, automobile air conditioning system classification (by power source)
Independent air conditioning: special power source (such as two internal combustion engines) drives the whole air conditioning system.
Verb (abbreviation of verb) automobile air conditioning system
Automobile air conditioning system refers to the output signals of various temperature sensors arranged inside and outside the car.
Maintenance of automobile air conditioner
First, the basic tools of automobile air conditioning maintenance
Second, the basic operation of automobile air conditioning and refrigeration system maintenance
Third, refrigerant replenishment.
Fourth, the air in the refrigeration system.
Verb (abbreviation of verb) Filling of refrigeration oil
Six, air conditioning system quality inspection
Seven, the quantitative detection of air conditioning system
Eight, refrigeration system performance experiment
Nine, dependent air conditioning system maintenance