Turbine wheel

Claim 1

A TURBINE WHEEL COMPRISING A DISC-LIKE BODY SECTION, A CIRCUMFERENTIALLY CONTINUOUS ANNULAR PEDESTAL PORTION FORMED INTEGRALLY WITH AND CARRIED BY SAID BODY SECTION PERIPHERALLY THEREOF, AND A PLURALITY OF CIRCUMFERENTIALLY SPACED RADIALLY DIRECTED TURBINE BLADES FORMED INTEGRALLY WITH AND CARRIED BY SAID PEDESTAL PORTION PERIPHERALLY THEREOF, SAID PEDESTAL PORTION COMPRISING A PLURALITY OF CIRCUMFERENTIALLY SPACED RADIALLY DIRECTED SUPPORTING STRUTS FORMED INTEGRALLY WITH AND POSITIONED ABOUT SAID DISC BODY SECTION IN A MANNER CAUSING EACH OF SAID SUPPORTING STRUTS TO BE RADIALLY INWARDLY OF AND IN GENERAL RADIAL ALIGNMENT WITH AT LEAST ONE OF SAID PLURALITY OF TURBINE BLADES, A PLURALITY OF RADIALLY DIRECTED WALL PORTIONS, EACH OF SAID WALL PORTIONS BEING RESPECTIVELY FORMED INTEGRALLY WITH AND JOINING SUCCESSIVE ONES OF SAID SPACED SUPPORTING STRUTS, AT LEAST SELECTED ONES OF SAID WALL PORTIONS HAVING FORMED THEREIN A RADIALLY DIRECTED STRUCTURALLY WEAKENED AREA SO AS TO DEFINE A GENERALLY RADIALLY DIRECTED AREA FOR LOCALIZING THERMALLY INDUCED STRESS CONCENTRATION THEREBY ENHANCING THE OPPORTUNITY FOR RADIALLY DIRECTED CRACKS TO BE FORMED THROUGH SAID AREAS OF STRESS CONCENTRATION WHENEVER SAID TURBINE WHEEL IS FIRST CAUSED TO EXPERIENCE A RADIAL TEMPERATURE GRADIENT AND SUBSEQUENTLY PERMITTED TO EXPERIENCE A REDUCTION IN SAID TEMPERATURE GRADIENT, AND A RELATIVELY THIN ANNULAR AXIALLY EXTENDING RIM FORMED INTEGRALLY WITH AND INTERCONNECTING EACH OF SAID STRUTS SO AS TO BE INTERMEDIATE OF SAID STRUTS AND TURBINE BLADES, THE RADIALLY OUTERMOST PORTION OF SAID STRUTS HAVING AN OUTER PERIPHERY OF A PATTERN APPROXIMATING THE CROSS-SECTIONAL CONFIGURATION OF THAT PORTION OF THE TURBINE BLADE IMMEDIATELY ADJACENT THE RIM.