Centrifugal gas compressor unit

Claim 1

A centrifugal gas compressor unit, comprising: a plurality of separate, gas compressor housings; a plurality of successive gas compressing stages within each of said housings; means for admitting gas to a first of said housings; means for discharging compressed gas from a last of said housings; means for communicating gas between each of said housings for successive gas compression; said stages each comprising a bladed gas compressor impeller and vaned diffusor; a shaft confined within each of said housings rotatably supporting said impellers; and bearing means interposed between each of said shafts and housings for supporting said shafts for rotation; wherein at least one of said impeller shafts is substantially circular in cross-section, having a central locus and at least one portion on The circumferential surface thereof which is eccentric, defining of said circumferential surface a first segment located a first radial distance from said locus, and a second segment located a second radial distance from said locus: at least one of said impellers of said one shaft has a substantially circular shaft mounting hole formed therein, said mounting hole having a radial center and at least one portion on the circumferential surface of said mounting hole which is eccentric, defining of said latter circumferential surface a first arcuate portion located a first radial distance from said center; and a second arcuate portion located a second radial distance from said center; and said shaft circumferential surface and said impeller mounting hole dimensionally define a mutual, slidable engagement and interface, upon one of said first and second segments being disposed in common, radial alignment and juxtaposition with one of said first and second arcuate portions, and define a torqued, interference fit, upon a portion of said second segment being disposed in common, radial alignment and juxtaposition with a portion of said first arcuate portion.