Refrigerator cooling system and method for defrosting refrigerator

A method for defrosting a refrigerator, applied to a refrigerator cooling system of the refrigerator having a throttle device, an evaporator, a compressor, a condenser, a backflow trunk section in communication with the evaporator and the compressor and a gasification branch provided in parallel with the backflow trunk section, the method comprising:

• obtaining an actual working time of the throttling device in a throttling working mode;
• and
• in response to that the actual working time reaches a preset time, switching a working mode of the throttling device from the throttling working mode to a defrosting working mode;
• in response to the throttling device being in the throttling working mode, switching the refrigerant from the backflow trunk section to flow back to the compressor;
• and
• in response to the throttling device being in the defrosting working mode, switching the refrigerant from the gasification branch to flow back to the compressor,
• wherein the condenser has a first heat release mode corresponding to the throttling working mode and a second heat release mode corresponding to the defrosting working mode, and a heat release amount of a refrigerant flowing through the condenser in the second heat release mode is smaller than a heat release amount of the refrigerant flowing through the condenser in the first heat release mode.

A refrigerator cooling system, comprising:

• a refrigerant circulation flow path provided with a compressor, a condenser, a throttling device and an evaporator,
• wherein the throttling device comprises:
• a first three-way valve including three first communication ports in communication with one another, two of the three first communication ports in communication with the refrigerant circulation flow path;
• and
• a throttling branch including a capillary tube, an end of the throttling branch in communication with a remaining first communication port, another end of the throttling branch in communication with the evaporator,
• wherein:
• the throttling device has a throttling working mode and a defrosting working mode, and a working mode of the throttle device is configured to switch between the throttling working mode and the defrosting working mode;
• in response to the throttling device being in the throttling working mode, the first three-way valve switches the refrigerant on the refrigerant circulation flow path from the condenser to flow through the throttling branch, and then flow through the evaporator;
• and
• in response to the throttling device being in the defrosting working mode, the first three-way valve switches the refrigerant on the refrigerant circulation flow path from the condenser to directly flow through the evaporator;
• and
• wherein the condenser has a first heat release mode corresponding to the throttling working mode and a second heat release mode corresponding to the defrosting working mode, and a heat release amount of a refrigerant flowing through the condenser in the second heat release mode is smaller than a heat release amount of the refrigerant flowing through the condenser in the first heat release mode.