| 摘要 |
PROBLEM TO BE SOLVED: To provide a system for controlling the number of compressors, capable of producing a compressed air in a manner quickly following a use load of the compressed air with a simple structure.SOLUTION: An operating number controller 5 changes the number of operating compressors 2 on the basis of a detection pressure of a pressure sensor 4. Each compressor 2 is subjected to capacity control between an upper limit pressure and a lower limit pressure so that a discharge pressure is maintained between the upper limit pressure and the lower limit pressure, wherein a load rate is 0% at the upper limit pressure or more and the load rate is 100% at the lower limit pressure or less. For each operating compressor, the load rate of each compressor 2 is determined on the basis of the detection pressure of the pressure sensor 4, a discharged air amount from each compressor 2 at the load rate is determined, and a total discharged air amount from the entire operating compressors is thereby determined. When the total discharged air amount is equal to or less than the total sum of the discharge capacities of other operating compressors excepting the next stop scheduled compressor, the next stop scheduled compressor is stopped. |
