Surge control mechanism for turbomachinery

Claim 1

A TURBOMACHINE COMPRISING: (A) A CASING HAVING A ROTATABLE SHAFT DISPOSED THEREIN, (B) AN IMPELLER MOUNTED ON SAID SHAFT, (C) AN INLET MEANS IN SAID CASING TO COMMUNICATE FLUID TO SAID IMPELLER, (D) A VOLUTE IN SAID CASING, (E) SAID VOLUTE COMMUNICATING WITH AN OUTLET MEANS IN SAID CASING, (F) AN INNER ANNULAR RING HAVING A PLURALITY OF DIFFUSERS CIRCUMFERENTIALLY SPACED THEREON DISPOSED IN SAID VOLUTE ADJACENT THE DISCHARGE TIP OF SAID IMPELLER TO RECEIVE FLUID BEING DISCHARGED FROM SAID IMPELLER, (G) AN OUTER ANNULAR RING DISPOSED IN SAID VOLUTE REMOTE FROM THE DISCHARGE TIP OF SAID IMPELLER, (H) A PLURALITY OF CONTROL BODIES CONNECTED TO SAID ANNULAR RING AND EXTENDING INWARDLY THEREFROM, (I) SAID CONTROL BODIES HAVING A LEADING EDGE THEREOF IN SPACED RELATIONSHIP WITH THE OUTLET END OF EACH OF SAID DIFFUSERS AND ADAPTED TO MOVE SUBSTANTIALLY ALONG THE AXIS OF SAID DIFFUSERS, (J) SAID INNER RING AND SAID OUTER RING TO ROTATE ABOUT THE AXIS OF SAID IMPELLER RELATIVE EACH OTHER WHEREBY SAID CONTROL BODY IS MOVED CORRESPONDINGLY THEREBY CHANGING THE FLUID FLOW CHARACTERISTICS OF THE FLUID BY CHANGING THE CROSS-SECTIONAL AREA OF THE FLOW PASS OF THE DIFFUSER TO INHIBIT STALLING OVER A WIDE RANGE OF FLOW TO PREVENT SURGE.