| 摘要 |
PURPOSE:To effectively utilize the economizer cycle by installing a pressure opening and closing valve which outputs a control signal so that a control valve in a gas introducing piping system is turned-ON when the load is 100% and the control valve is turned-OFF on unloading. CONSTITUTION:As for the actuator part of a slide valve 6, the left cylinder chamber 18a of a piston 17a has a high pressure, and the right cylinder chamber 18b has a low pressure. When the piston 17a comes to the position of a load capacity of 100% as shown in the figure, a capacity detecting port 19 is drilled at the position where the pressure at the capacity detecting port 19 varies from high pressure to low pressure. A pressure opening and closing device 25 for detecting the pressure variation at the capacity detecting port 19 turns-ON a solenoid valve 26 installed into a gas introducing pipe system 11, when the load capacity of a screw compressor 1 is 100%, and the economizer cycle is operated to introduce the coolant gas from a supercooler 8 to a gas injection port 20, and said coolant gas is jetted to the compression cycle of a screw rotor 2. In case of other loading or unloading, the solenoid valve 26 is turned- OFF, and the injection of coolant gas is automatically stopped.
|
