GB950057A - Improvements in or relating to rotary compressors - Google Patents

Abstract

950,057. Intermeshing screw pumps. SVENSKA ROTOR MASHINA A.B. March 24, 1960 [April 20, 1959], No. 13432/59. Addition to 832386. Heading F1F. A rotary gas compressor of the positive displacement type includes a casing having a working chamber comprising a pair of intersecting bores with end walls, male and female rotors located one in each bore and having at least three interengaging helical lobes and grooves, clearances between the rotors and between the rotors and their bores, and means for introducing a sealing and cooling liquid into the working chamber so that it enters the clearances and power to drive one rotor is transmitted from the other through the liquid, the ratio of the mass flow of the liquid to that of the gas being not less than one and a half, e.g. about four. In Fig. 1, one rotor of compressor 10 is driven by shaft 13 through reduction gearing, gas entering by duct 11 and leaving by duct 12. The other rotor drives pumps 15 and 16, the latter delivering oil from a reservoir 17 through cooler 20 to inlets feeding the clearances and bearings of the rotors. Most of this oil passes out with the compressed gas to a separator 22 whence it returns to the reservoir. Oil draining from the bearings is recirculated by pump 15. One liquid may be used for filling the clearances and cooling, and another for lubricating, pump 16 circulating the former and pump 15 the latter, Fig. 2 (not shown). The compressor casing may be in two halves separable along a plane through the rotor axes.