JPS6415484A - Rotor stabilizing device for screw compressor - Google Patents

Abstract

PURPOSE:To promote the extension of a life in a thrust bearing by forming a mechanism, which actuates each opening and closing means of a suction port being associated with that of a delivery port in a compressor, and a thrust generating means in a rotor shaft end part respectively by a hydraulically operated type and actuating the thrust generating means being associated with a load-unload selector valve. CONSTITUTION:In the case of a screw compressor having two air blocks 1(1A, 1B) compressing gas by rotating male and female rotors respectively meshing with each other, a hydraulic piston 16 with rack, serving as the mechanism which actuates a butterfly valve 17 with a pinion serving as the suction port opening and closing means being associated with a blow-off valve 18 serving as the delivery port opening and closing means, is provided. The compressor is switched in its load and unload operations by a four way type solenoid valve 15 controlling the operating direction of the hydraulic piston 16. While an unload oil pressure line of the four way type solenoid valve 15 communicates with a hydraulic piston, relating to a thrust generating means in a rotor shaft end part of the air block 1, through an orifice 13 and an oil head 14.