Radially compact fluid compressor

Claim 1

A centrifugal type of fluid compressor, comprising: an impeller assembly including a horizontally extending impeller having an outermost edge defining an outermost horizontal, circumferential path of movement and means for rotating said impeller in a given direction so as to drive its outermost edge through said circumferential path, and a compressor housing surrounding said impeller and together with the impeller defining a fluid collection chamber extending between a first upstream end and a second fluid exiting downstream end, said collection chamber progressively enlarging vertically from its upstream end to its downstream end, whereby fluid passing through said collection chamber from its upstream end to its downstream end progressively decreases in velocity and therefore progressively increases in static pressure, wherein said collection chamber does not enlarge horizontally outward relative to said outermost horizontal path of movement of said impeller at any point between its entry and exit end, whereby to minimize the maximum horizontal dimensions of the overall compression housing, wherein said collection chamber as it approaches its downstream exit end includes a section which extends vertically beyond said impeller, wherein said section of said collection chamber extending vertically beyond said impeller includes a segment thereof extending horizontally inward of said impeller, wherein said collection chamber defines a downwardly and inwardly spiralling path from its upstream end to its downstream exit end, wherein said upstream and downstream ends of said collection chamber are spaced about 180 degrees from one another about said outmost circumferential path of said impeller, wherein said collection chamber extends between said ends on one side of said path and wherein said compressor housing and said impeller together define a second substantially identical collection chamber on the opposite side of said path, between said ends, said second collection chamber spiralling downwardly and inwardly from said downstream end to said upstream end, whereby the upstream end of one collection chamber serves as the downstream end of the other and vice versa.