Abstract: A communication control system for a number of gas compressors where one gas compressor is set as a master gas compressor that controls communication with N slave gas compressors. A cycle of communication with the N slave compressors in N communication sets is defined as a total compressor number communication cycle. In first to Nth communication sets, a first response request is transmitted to each of the first to Nth gas compressors. When a response is received from one of the gas compressors, the system determines that connection with the one gas compressor has succeeded. When no response is received, the system determines that connection has failed. In following communication cycles, a second response request is transmitted to the slave compressors with which communication has succeeded. The first response request is then transmitted to the slave compressors with which the communication connection has failed using a different timing sequence.

Abstract: A technique is provided that can further reduce power at the time of “unload operation control” in a gas compressor that generates a compressed gas at a set pressure by constant-speed control. The gas compressor includes a compressor main unit, a drive source, an intake throttle valve, a gas release valve, rotation speed converting means, a pressure detecting device that detects a discharge pressure, and a controller that, the relationship between an upper-limit pressure H and a lower-limit pressure L being H>L, carries out opening the intake throttle valve and closing the gas release valve and operating the drive source at a full-load rotation speed until the discharge pressure reaches the upper-limit pressure H. The controller carries out at least one of closing the intake throttle valve and opening the gas release valve to reduce the discharge pressure to within a predetermined range when the discharge pressure reaches the upper-limit pressure H.

Abstract: An object of the present invention is to realize inexpensive and simple compressor number control of gas compressors. In order to achieve the above object, there is provided a gas compressor set as a master gas compressor that performs compressor number control on N slave gas compressors, the compressor including: a communication I/F that is communicable with the slave gas compressors; and a control unit.

Abstract: A technique is provided that can further reduce power at the time of “unload operation control” in a gas compressor that generates a compressed gas at a set pressure by constant-speed control. The gas compressor includes a compressor main unit, a drive source, an intake throttle valve, a gas release valve, rotation speed converting means, a pressure detecting device that detects a discharge pressure, and a controller that, the relationship between an upper-limit pressure H and a lower-limit pressure L being H>L, carries out opening the intake throttle valve and closing the gas release valve and operating the drive source at a full-load rotation speed until the discharge pressure reaches the upper-limit pressure H. The controller carries out at least one of closing the intake throttle valve and opening the gas release valve to reduce the discharge pressure to within a predetermined range when the discharge pressure reaches the upper-limit pressure H.

Abstract: An object is to proceed with a contract-concluding process for an operational data transaction simply, conveniently and clearly. A fluid machine including: a driving source; a fluid machine body that generates a fluid by a driving force of the driving source; a controller that has a GUI allowing an external input and output, and controls driving of the driving source; and a communication apparatus that allows communication with an external server via a wired or wireless communication line.