Optical system for machines

Claim 1

A MACHINE TOOL, INCLUDING, IN COMBINATION: A DRIVING MOTOR HAVING AN OUTPUT SHAFT EXTENDING ALONG A FIRST AXIS; MEANS FOR SUPPORTING A WORKPIECE ON SAID SHAFT FOR ROTATION ABOUT SAID FIRST AXIS; A TOOL CARRIAGE SUPPORTED FOR MOTION ALONG SECOND AND THIRD PERPENDICULAR AXES, ONE OF WHICH IS PARALLEL TO SAID FIRST AXIS AND THE OTHER OF WHICH IS PERPENDICULAR THERETO; A CUTTING TOOL; MEANS FOR SUPPORTING THE CUTTING TOOL ON THE CARRIAGE FOR ROTATION ABOUT AN AXIS PERPENDICULAR TO SAID FIRST, SECOND, AND THIRD AXES, SAID SUPPORT MEANS COMPRISING A CYLINDRICAL BEARING MEMBER HAVING ITS CENTRAL AXIS PERPENDICULAR TO SAID FIRST, SECOND AND THIRD AXES, AND AN EXTENSION ARM JOURNALLED IN SAID BEARING AND CONNECTED TO SAID CUTTING TOOL, SAID BEARING MEMBER HAVING A CENTRAL APERTURE THERETHROUGH; AND AN OPTICAL SYSTEM INCLUDING A SOURCE OF ILLUMINATION AND A LENS PROJECTION SYSTEM OPERATIVE TO FORM A BEAM OF LIGHT PASSING THROUGH SAID APERTURE IN THE BEARING AND THE POINT OF CONTACT BETWEEN SAID CUTTING TOOL AND SAID WORKPIECE SO AS TO PROJECT AN IMAGE OF SUCH AREA FOR VISUAL INSPECTION BY A MACHINE OPERATOR.