GB1007236A - Oil scavenging system for a rotary compressor - Google Patents

Abstract

1,007,236. Rotary compressors. JAEGER MACHINE CO. Aug. 4, 1964 [Sept. 5, 1963], No. 29264/64. Heading F 1 F. A multi-stage rotary compressor having an interstage manifold and a high-pressure oil lubricating system includes means for preventing excessive accumulation of oil in the manifold which comprises a line connecting the manifold to a source of higher pressure on the compressor to provide a pressure differential which creates a jet of fluid in the manifold to remove the oil therefrom. As shown in Fig. 5, a two-stage rotary compressor, preferably of the sliding vane type, comprising a low-pressure stage receiving air from atmosphere through an inlet valve 30 and a high pressure stage 12 discharging an oil-air mixture through a line 17 into an air-receiver 18 includes an interstage manifold 13 connected by a line 24 fitted with a filter 25, check valve 26 and a choke 27 to an oil-separator 20 through which air at discharge pressure from the receiver 18 passes. The separator 20 being at higher pressure than the manifold 13 creates a jet of fluid to remove oil from the manifold when the compressor is unloaded and little or no air is flowing through the compressor. A line 38 connected to the air supply conduit between the separator 20 and a non-return check valve 29 transmits pressure to act on a diaphragm-actuator, spring-loaded valve 36 which when the pressure reaches a predetermined value opens to supply pressure fluid through a line 37 to an actuator to close the inlet valve 30 supplying the compressor. In a modification, the line from the separator 20 is connected to the valve 36 to supply the pressure to open this valve and supply the actuator to close the valve 30. A line from the actuator fitted with a filter, check valve and choke then connects to the manifold. In this case a jet is created only when the valve 36 is open and the valve 30 closed to unload the compressor. In a further modification of the Fig. 5 embodiment, a pump driven by the compressor fitted in the line 24 increases the pressure differential. In a still further modification of the Fig. 5 embodiment, an additional line fitted with a filter, check valve and choke is provided between the manifold and the chamber of the actuator associated with the inlet valve 30. This line being supplied with pressure fluid from the line 38 when the valve 36 is open and the valve 30 closed so that in the unloaded condition of the compressor two fluid jets are removing oil from the manifold. Specification 772,944 is referred to.