Patent ID: 8375740

Claim:
An air conditioner comprising: a plurality of compressors having different capacities; a plurality of oil separators connected to respective outlets of the compressors to separate oil from refrigerant discharged from the compressors; a plurality of oil collection pipes respectively connected to the oil separators to collect oil separated by the oil separators, wherein the oil collection pipes comprise capillaries, respectively, to reduce pressure of oil, wherein the capillaries have different diameters corresponding to the capacities of the compressors such that the diameter of a capillary corresponding to a high-capacity compressor is larger than that of a capillary corresponding to a low-capacity compressor; a common inlet pipe to receive oil separated by the oil separators and to receive refrigerant and to allow the oil and refrigerant to flow to the compressors; a plurality of branch inlet pipes branching off from the common inlet pipe and respectively connected to the compressors; a common oil collection pipe at which streams of oil from the oil collection pipes gather; and an accumulator connected to the common inlet pipe to separate liquid and gas portions of the refrigerant, wherein the plurality of oil collection pipes are connected to the common oil collection pipe and the common oil collection pipe being directly connected to the common inlet pipe.