| 摘要 |
PURPOSE:To prevent an oil level in each compressor from getting unbalanced, by feeding one compressor with separated lubricating oils, while making a device so as to feed the lubricating oil to other compressors from this compressor through an equalizing pipe. CONSTITUTION:When all compressors 1, 2 and 3 are operated, oil containing about 0.5wt% of a regular refrigerant circulating quantity is returned to an oil separator 9 together with refrigerating gas evaporated inside a suction pipe 8 for a refrigerating cycle. Hereat, a part of the separated oils and gases pass through a branch pipe 10 and is fed to a motor chamber 14 of a first compressor 1, then the oil is further fed to a compression element chamber 13 by way of an equalized oil chech valve 18. At this time, a pressure loss in a suction branch pipe of each compressors 1-3 is designed to make the pressure loss of a suction branch pipe 41 of the second compressor 2 and a suction branch pipe 42 of the third branch pipe 3 larger than a branch pipe 10 of the first compressor 1 so that a superfluous quantity in the oils fed to a compression element chamber of the first compressor 1 passes through each of equalizing pressure and oil pipes 4 and 6, and is fed to the second compressor 2 and the third compressor 3, thus it can normally accomplish a lubricating function. |
