| 摘要 |
PURPOSE:To reduce shaft power remarkably in unload running by a method wherein the air in an oil seprator is discharged to the intended pressure and the pressure ratio of a compressor is made smaller than conventional one. CONSTITUTION:When a compressor 1 is in unload running, the air in the oil separator 5 is discharged from a pipe 21 to an inlet port 9i through a pipe 25. Thus, the air in the oil separator 5 keeps the set-up pressure (e.g. 4kg/cm<2>) of a pressure regulating valve 20. In this way, since the air in the oil separator 5 is released down to the intended pressure in unload running, the pressure ratio of the compressor 1 (the value given by the pressure in the discharge passage divided by the pressure in the suction passage) becomes smaller than conventionally and as a result the shaft in unload running can be reduced remarkably. |
