1、 Temperature control system (core: bidirectional adjustment of heating and cooling)

1. Working principle of heating system

• Core component: Stainless steel heating tube (or far-infrared heater), installed in the air duct of the box.
• Work logic: The temperature sensor real-time collects the temperature inside the box, and compares it with the set temperature. When the temperature inside the box is lower than the set value, the controller outputs a signal to start the heating tube. After the heating tube generates heat, the circulating fan blows hot air into the box to form a uniform hot air circulation; When the temperature reaches the set value, the heating tube is powered off and stops working, achieving constant temperature.

2. Working principle of refrigeration system (commonly used compressor refrigeration)

• Core components: compressor, condenser, evaporator, throttling device (capillary/expansion valve).
• Working logic: When the temperature inside the box is higher than the set value, the refrigeration system starts the compressor to compress the gaseous refrigerant (such as R404A) into high-temperature and high-pressure gas, and sends it to the condenser for cooling and liquefaction; After being depressurized by the throttling device, the liquid refrigerant enters the evaporator to absorb the heat from the air inside the box (achieving air cooling), evaporates into a gaseous state, and then returns to the compressor to form a cycle; The cooled cold air is sent into the box by the fan until the temperature drops to the set value.

2、 Humidity control system (core: bidirectional regulation of humidification and dehumidification)

1. Working principle of humidification system (commonly used steam humidification/ultrasonic humidification)

• Steam humidification: The humidification water tank at the bottom of the box is heated by an electric heating tube to evaporate water and produce steam. The circulating fan brings the steam into the box to increase the air humidity;
• Ultrasonic humidification: The ultrasonic oscillator turns water mist into tiny water droplets, which diffuse into the box with circulating air, and the water droplets naturally evaporate to increase humidity.
• Control logic: The humidity sensor collects real-time humidity, starts humidification when it is below the set value, and stops when it reaches the set value.

2. Working principle of dehumidification system (commonly used for freeze dehumidification)

• Core components: shared evaporator with the refrigeration system (or independent dehumidification evaporator).
• Working logic: When the humidity inside the box is higher than the set value, the dehumidification mode is activated. The circulating air passes through the low-temperature evaporator, and the water vapor in the air condenses into water droplets when it encounters cold water, which are then dropped into the water tray and discharged; The dehumidified dry air returns to the box until the humidity drops to the set value.

3、 System collaboration logic