Cooling device and cooling method for cooling refrigerant of vehicle air conditioner

The invention provides a cooling device for cooling refrigerant of a vehicle air conditioner. The cooling device comprises a water storing device, a heat exchanging tube and a pump. The water storing device is used for collecting condensate of the vehicle air conditioner; the heat exchanging tube is sleeved on the exterior of an inlet tube of an expansion valve of the vehicle air conditioner to form a flowing channel of condensate; and the pump is used for pumping the condensate in the water storing device into the heat exchanging tube. The invention further provides a cooling method for cooling the refrigerant of the vehicle air conditioner. The cooling method includes firstly collecting the condensate of the air conditioner into the water storing device, and secondly cooling the condensate in the inlet tube of the expansion valve of the vehicle air conditioner by utilizing the condensate. According to the cooling device, the condensate produced during the operation of the vehicle air conditioner is collecte