"Cooling Fan Manufacturer" by controlling the triac conduction angle, so that the output voltage is changed, so that the input voltage applied to the fan is changed to adjust the fan speed to achieve stepless adjustment of each stall wind speed. This module is used as a temperature sensor DS18B20, AT89C51 as the processor, together with the temperature display output as a temperature control unit. Whole "Cooling Fan Manufacturer" system is simple and strive structure, complete functions. The system works as follows: DS18B20 temperature measurement site, the measurement data into AT89C51 the P3.7 mouth, after microcontroller processing temperature is displayed and compared with the set value of the upper and lower temperature limits, if higher than "Cooling Fan Manufacturer"an upper limit or below the lower limit value of the motor speed control setting adjustment.