Air-cooled refrigerator, and control method, control system and controller for defrosting thereof

Abstract

An air-cooled refrigerator and a control method, a control system and controller for defrosting thereof are provided. The high-temperature air of the air-cooled refrigerator exchanges heat with the evaporator in the air duct and is sent into a refrigerating compartment through the operation of a fan; when the evaporator is gradually frosted, the heat-exchanged air suffers the resistance from the frosts on the evaporator during the flow and the fan slows down. Based on this principle, the fan speed can directly correspond to the frost accumulation mass of the evaporator. The actual frost accumulation mass of the evaporator can be directly determined by determining the fan speed. When the fans peed is decreased to a certain low speed, it means that there is much frost on the evaporator and the defrosting needs to be started timely. As a result, the problems of large energy consumption and poor fresh-keeping effect caused by the traditional control method of defrosting in advance or delayed defrosting can be solved, and the energy-saving and fresh-keeping effects of the air-cooled refrigerator can be improved.

1 . A method, comprising:
 collecting a first fan speed of a fan of an evaporator of a refrigerator during a stable operation of the refrigerator;   determining whether the first fan speed is less than or equal to a threshold speed; and   performing a defrosting operation on the evaporator in response to the first fan speed less than or equal to the threshold speed.   
     
     
         2 . The method of  claim 1 , wherein a heater is employed to defrost the evaporator during the defrosting operation. 
     
     
         3 . The method of  claim 1 , wherein the collecting the first fan speed includes:
 allowing the fan to operate at a rated voltage, and   determining the first fan speed by detecting a feedback signal of an electric control loop of the fan.   
     
     
         4 . The method of  claim 1 , comprising:
 after the defrosting operation is performed,
 collecting a temperature of the evaporator; 
 determining whether the temperature of the evaporator reaches a threshold temperature; and 
 stopping the defrosting when in response to the temperature of the evaporator reaches the threshold temperature. 
   
     
     
         5 . The method of  claim 1 , comprising:
 before collecting the first fan speed during the stable operation of the refrigerator,
 collecting a second fan speed and a third fan speed of the fan before and after a first time period, respectively; 
 determining whether a difference between the second fan speed and the third fan speed is less than or equal to a threshold speed difference; and 
 determining that the refrigerator is the stable operation in response to it is determined that the difference between the second fan speed and the third fan speed is less than or equal to the threshold speed difference. 
   
     
     
         6 . A refrigerator, comprising a refrigerator body, an evaporator, an evaporating fan, a defrosting assembly, and a controller, the controller including:
 a data receiver circuit that acquires a temperature of the evaporator and a fan of the evaporating fan;   a determiner circuit configured to perform actions including;
 collecting a first fan speed of the evaporating fan during a stable operation of the refrigerator; 
 determining whether the fan speed is less than or equal to a threshold speed; and 
 determining a defrosting operation on the evaporator based on a result of the determining whether the fan speed R is less than or equal to the threshold speed; and 
   a signal sender that controls the defrosting assembly to perform the defrosting operation determined by the determiner circuit, wherein the defrosting operation include starting defrosting, not starting defrosting, continuing defrosting, or stopping defrosting.   
     
     
         7 . The refrigerator of  claim 6 , wherein the evaporating fan is disposed in an air duct of the refrigerator body; and
 the controller is connected with the evaporating, fan and the defrosting assembly through an electric control circuit, respectively.   
     
     
         8 . The refrigerator of  claim 7 , further comprising an evaporator sensor electrically connected with the controller and configured to detect the temperature of the evaporator;
 wherein during the defrosting operation performed by the defrosting assembly, the controller determines whether the defrosting assembly stops the defrosting operation based on the temperature of the evaporator detected by the evaporator sensor.   
     
     
         9 . The refrigerator of  claim 7 , wherein the defrosting assembly includes a heater arranged at a bottom of the evaporator. 
     
     
         10 . A computing device comprising a memory, a processor, and computer programs stored on the memory and executable by the processor, wherein the processor is configured to, when executing the computer programs, perform actions including:
 collecting a first fan speed of a fan of an evaporator of a refrigerator during a stable operation of the refrigerator;   determining whether the first fan speed is less than or equal to a threshold speed; and   control a defrosting assembly of the refrigerator to perform a defrosting operation on the evaporator in response to the first fan speed is less than or equal to the threshold speed.   
     
     
         11 - 12 . (canceled) 
     
     
         13 . The computing device of  claim 10 , wherein the collecting the fan speed includes:
 allowing the fan to operate at a rated voltage, and   determining the first fan speed by detecting a feedback signal of an electric control loop of the fan.   
     
     
         14 . The computing device of  claim 10 , wherein the actions include:
 after the defrosting operation is performed,
 collecting a temperature of the evaporator; 
 determining whether the temperature of the evaporator reaches a threshold temperature; and 
 stopping the defrosting when the temperature of the evaporator reaches the threshold temperature. 
   
     
     
         15 . The computing device of  claim 10 , wherein the actions include:
 before collecting the first fan speed during the stable operation of the refrigerator,
 collecting a second fan speed and a third fan speed of the fan before and after a first time period, respectively; 
 determining whether a difference between the second fan speed and the third fan speed is less than or equal to a threshold speed difference; and 
 determining that the refrigerator is the stable operation in response to it is determined that the difference between the second fan speed and the third fan speed is less than or equal to the threshold speed difference. 
   
     
     
         16 . The refrigerator of  claim 6 , comprising a compressor, a condenser, and a capillary tube,
 wherein the compressor, the condenser, the capillary tube, and the evaporator together constitute a refrigerant circulation loop, and the evaporator is disposed in an air duct of the refrigerator body