Multi-stage axial compressor

Claim 1

IN A MULTI-STAGE AXIAL COMPRESSOR SUITABLE FOR INTERMITTENT BLEEDING OF COMPRESSED AIR THEREFROM AND HAVING A LONGITUDINAL AXIS, A MAIN FLUID DUCT, AND CASING MEANS FOR SAID MAIN FLUID DUCT, SAID CASING MEANS COMPRISING FIRST AND SECOND AXIALLY SPACED SECTIONS AND AN INTERMEDIATE SECTION EXTENDING BETWEEN SAID FIRST AND SECOND SECTIONS, EACH OF SAID SECTIONS HAVING AN INNER SURFACE WHICH FORMS AN OUTER BOUNDARY WALL OF A RESPECTIVE AXIAL PORTIONS OF SAID MAIN FLUID DUCT, THE INNER SURFACE OF SAID FIRST SECTION HAVING A DOWNSTREAM END, AND THE INNER SURFACE OF SAID SECOND SECTION HAVING AN UPSTREAM END WHICH IS ALIGNED AXIALLY OF THE COMPRESSOR WITH THE DOWNSTREAM END OF THE INNER SURFACE OF SAID FIRST SECTION, THE INNER SURFACE OF SAID INTERMEDIATE SECTION BEING FLUID TIGHT AND DIVERGING OUTWARDLY RELATIVELY TO THE INNER SURFACES OF THE FIRST AND SECOND SECTIONS FROM THE DOWNSTREAM END OF THE INNER SURFACE OF SAID FIRST SECTION TOWARDS AND IN RADIALLY OUTWARDLY SPACED RELATIONSHIP TO THE UPSTREAM END OF SAID SECOND SECTION, THE INNER SURFACE OF SAID INTERMEDIATE SECTION AND THE UPSTREAM END OF SAID SECOND SECTION DEFINING AN ANNULAR SPACE THEREBETWEEN, SAID CASING MEANS BEING PROVIDED WITH DUCT MEANS IN FLUID FLOW COMMUNICATION WITH SAID ANNULAR SPACE FOR BLEEDING COMPRESSED AIR FROM SAID MAIN FLUID DUCT, THE IMPROVEMENT COMPRISING A PLURALITY OF ANGULARLY ARRANGED STATOR BLADES PROVIDED IN SAID INTERMEDIATE SECTION, EACH OF THE STATOR BLADES CARRYING AT ITS RADIALLY OUTER END A PLATFORM FORMED INTEGRALLY THEREWITH AND HAVING A RADIALLY INWARDLY FACING SURFACE, THE RADIALLY INWARDLY FACING SURFACE OF SAID PLATFORMS OF SAID STATOR BLADES TOGETHER FORMING SAID FLUID TIGHT INNER SURFACE OF SAID INTERMEDIATE SECTION.