Inspection method and machine

Claim 1

A METHOD FOR INSPECTING AN OBJECT FOR DEFECTS WHICH REPRESENT, WITH RESPECT TO ONE AXIS OF THE OBJECT, CIRCUMFRENTIAL VARIATIONS IN THE CONDUCTIVITY OF THE OBJECT FOR THE TYPE OF RADIANT ENERGY HEREINAFTER DEFINED INCLUDING THE STEPS OF PROJECTING A BEAM OF RADIANT ENERGY FROM A SOURCE THEREOF THROUGH THE OBJECT IN A DIRECTION TRANSVERSE TO SAID AXIS, SAID BEAM OF RADIANT ENERGY BEING OF A TYPE WHICH IS CAPABLE OF BEING TRANSMITTED THROUGH THE OBJECT WITH A REDUCTION IN BEAM INTENSITY PROPORTIONAL TO THE RADIANT ENERGY CONDUCTIVITY OF THE OBJECT, CAUSING RELATIVE MOVEMENT BETWEEN THE OBJECT AND BEAM IN THE DIRECTION OF SAID AXIS AT A PREDETERMINED VELOCITY OF CAUSE THE LEADING AND TRAILING EDGES AND OTHER CIRCUMFERENTIALLY CONTINUOUS AXIAL VARIATIONS IN SAID CONDUCTIVITY OF THE OBJECT TO MODULATE THE INTENSITY OF SAID BEAM AT A FIRST FREQUENCY CORRESPONDING TO THE RELATIVE AXIAL VELOCITY BETWEEN THE BEAM AND THE OBJECT, SIMULTANEOUSLY ROTATING THE OBJECT ABOUT SAID AXIS WITH A PREDETERMINED ANGULAR VELOCITY SUFFICIENT TO PRODUCE A SURFACE VELOCITY OF THE OBJECT RELATIVE TO THE BEAM SUBSTANTIALLY GREATER THEN THE AXIAL VELOCITY THEREOF TO CAUSE SAID CIRCUMFERENRTIAL CONDUCTIVITY VARIATIONS IN THE OBJECT TO MODULATE THE INTENSITY OF SAID BEAM AT A SECOND FREQUENCY CORRESPONDING TO THE ANGULAR VELOCITY OF THE OBJECT, TRANSLATING SAID MODULATED BEAN INTO AN ELECTRICAL SIGNAL, THE AMPLITUDE OF WHICH VARIES IN PROPORTION TO VARIATIONS IN THE INTENSITY OF SAID MODULATED BEAM AND UTILIZING THOSE VARIATIONS IN THE SECOND FREQUENCY SINGAL WHICH EXCEED A PREDETERMINED AMPLITUDE FOR INDICATING THAT THE OBJECT CONTAINS A CIRCUMFERENTIALLY NON-CONTINUOUS DEFECT OF THE ABOVE TYPE.

Claim 2

A METHOD FOR INSPECTING AN OBJECT FOR DEFECTS WHICH REPRESENT, WITH RESPECT TO ONE AXIS OF THE OBJECT, CIRCUMFRENTIAL VARIATIONS IN THE CONDUCTIVITY OF THE OBJECT FOR THE TYPE OF RADIANT ENERGY HEREINAFTER DEFINED INCLUDING THE STEPS OF PROJECTING A BEAM OF RADIANT ENERGY FROM A SOURCE THEREOF THROUGH THE OBJECT IN A DIRECTION TRANSVERSE TO SAID AXIS, SAID BEAM OF RADIANT ENERGY BEING OF A TYPE WHICH IS CAPABLE OF BEING TRANSMITTED THROUGH THE OBJECT WITH A REDUCTION IN BEAM INTENSITY PROPORTIONAL TO THE RADIANT ENERGY CONDUCTIVITY OF THE OBJECT, CAUSING RELATIVE MOVEMENT BETWEEN THE OBJECT AND BEAM IN THE DIRECTION OF SAID AXIS AT A PREDETERMINED VELOCITY OF CAUSE THE LEADING AND TRAILING EDGES AND OTHER CIRCUMFERENTIALLY CONTINUOUS AXIAL VARIATIONS IN SAID CONDUCTIVITY OF THE OBJECT TO MODULATE THE INTENSITY OF SAID BEAM AT A FIRST FREQUENCY CORRESPONDING TO THE RELATIVE AXIAL VELOCITY BETWEEN THE BEAM AND THE OBJECT, SIMULTANEOUSLY ROTATING THE OBJECT ABOUT SAID AXIS WITH A PREDETERMINED ANGULAR VELOCITY SUFFICIENT TO PRODUCE A SURFACE VELOCITY OF THE OBJECT RELATIVE TO THE BEAM SUBSTANTIALLY GREATER THEN THE AXIAL VELOCITY THEREOF TO CAUSE SAID CIRCUMFERENRTIAL CONDUCTIVITY VARIATIONS IN THE OBJECT TO MODULATE THE INTENSITY OF SAID BEAM AT A SECOND FREQUENCY CORRESPONDING TO THE ANGULAR VELOCITY OF THE OBJECT, TRANSLATING SAID MODULATED BEAN INTO AN ELECTRICAL SIGNAL, THE AMPLITUDE OF WHICH VARIES IN PROPORTION TO VARIATIONS IN THE INTENSITY OF SAID MODULATED BEAM AND UTILIZING THOSE VARIATIONS IN THE SECOND FREQUENCY SINGAL WHICH EXCEED A PREDETERMINED AMPLITUDE FOR INDICATING THAT THE OBJECT CONTAINS A CIRCUMFERENTIALLY NON-CONTINUOUS DEFECT OF THE ABOVE TYPE.