Blower

Claim 1

A TURBO-MACHINE IMPELLER OF THE CENTRIFUGAL TYPE HAVING AN INLET, AND OUTLET, A HUB SECTION CONNECTED TO AN OUTER SECTION BY A PLURALITY OF BLADES PROJECTING RADIALLY OUTWARDLY FROM SAID HUB SECTION, EACH SAID BLADE HAVING AN OUTER EDGE COMPRISING AN ARCUATE FORWARD PORTION HAVING A SUBSTANTIALLY CONSTANT RADIUS OF CURVATURE AND A REARWARD PORTION LYING IN A PLANE THE EXTENSION OF WHICH FORMS AN INCLUDED ANGLE BETWEEN 81* AND 90* WITH THE AXIS OF ROTATION OF SAID IMPELLER, THE CENTER OF SAID RADIUS OF CURVATURE LYING IN A PLANE DISPOSED NORMAL TO THE AXIS OF ROTATION OF SAID IMPELLER AND CONTAINING THE PERIPHERY OF THE INLET, SAID CENTER BEING DISPOSED RADIALLY OUTWARD FROM SAID AXIS OF ROTATION BY AN AMOUNT BETWEEN 0.30 AND 0.49 TIMES THE OUTLET DIAMETER OF SAID IMPELLER; AN INNER EDGE COMPRISING AN ARCUATE FORWARD PORTION HAVING A SUBSTANTIALLY CONSTANT RADIUS OF CURVATURE AND A REARWARD PORTION LYING IN A PLANE DISPOSED SUBSTANTIALLY NORMAL TO THE AXIS OF ROTATION OF SAID IMPELLER, THE CENTER OF SAID RADIUS OF CURVATURE LYING IN A PLANE DISPOSED NORMAL TO THE AXIS OF ROTATION OF SAID IMPELLER AND UPSTREAM OF A PLANE CONTAINING THE PERIPHERY OF SAID INLET BY AN AMOUNT BETWEEN 0.06 AND 0.12 TIMES THE OUTLET DIAMETER OF SAID IMPELLER, SAID CENTER BEING DISPOSED RADIALLY OUTWARD FROM SAID AXIS OF ROTATION BY AN AMOUNT BETWEEN 0.25 AND 0.45 TIMES THE OUTLET DIAMETER OF SAID IMPELLER; AND A REARWARD PORTION FORMED ARCUATELY BACKWARDLY CURVED TO PROVIDE A SUBSTANTIALLY UNIFORM EXPANSION OF A PRESSURIZED FLUID THAT MAY FLOW THROUGH THE IMPELLER SUCH THAT THE RATIO OF THE DENSITY OF THE FLUID AT THE IMPELLER OUTLET TO THE DENSITY OF THE FLUID IMMEDIATELY UPSTREAM OF SAID BACKWARDLY CURVED PORTION IS BETWEEN 0.825 AND 0.915.