Combined bore diameter and concentricity gauge

Claim 1

A COMBINED BORE DIAMETER AND CONCENTRICITY GAUGE FOR USE WITH A DIAL INDICATOR HAVING A RECIPROCABLE OPERATING PLUNGER AND ADAPTED TO SELECTIVELY MEASURE THE DIAMETER OF A WORKPIECE BORE AND ITS CONCENTRICITY RELATIVELY TO A WORKPIECE COUNTERBORE, SAID GAUGE COMPRISING A DIAL INDICATOR HOLDER HAVING THEREIN A SOCKET AND HAVING MEANS THEREON FOR ATTACHING THERETO A DIAL INDICATOR WITH ITS OPERATING PLUNGER DISPOSED IN COMMUNICATION WITH SAID SOCKET, AN ELONGATED HOLLOW SUPPORTING STRUCTURE HAVING A FORWARD POSITION INSERTABLE IN THE WORKPIECE BORE, AN INTERMEDIATE PILOT PORTION ADAPTED TO SNUGLY BUT ROTATABLY FIT THE WORKPIECE COUNTERBORE, AND A REARWARD PORTION ROTATABLY MOUNTED IN SAID SOCKET; SAID SUPPORTING STRUCTURE HAVING A LONGITUDINAL BORE THERETHROUGH COMMUNICATING AT ITS REARWARD END WITH SAID SOCKET AND HAVING IN SAID FORWARD PORTION A TRANSVERSE BORE COMMUNICATING WITH SAID LONGITUDINAL BORE, A TRANSVERSELY-RECIPROCABLE BORE MEASURING MEMBER RECIPROCABLY MOUNTED IN SAID TRANSVERSE BORE AND HAVING A WORKPIECE BORE-CONTACTING FEELER PORTION THEREON, SAID BORE MEASURING MEMBER HAVING THEREIN A MOTION-TRANSMITTING EDGE PORTION, ELONGATED MOTION-TRANSMITTING MEANS RECIPROCABLY MOUNTED IN AND EXTENDING THROUGH SAID LONGITUDINAL BORE FROM SAID MOTION-TRANSMITTING EDGE INTO SAID DIAL INDICATOR HOLDER SOCKET AND ADAPTED TO ENGAGE THE DIAL INDICATOR PLUNGER, SAID MOTION-TRANSMITTING MEANS BEING RESPONSIVE TO THE TRANSVERSE RECIPROCATION OF SAID MEASURING MEMBER FOR EFFECTING RECIPROCATION OF THE DIAL INDICATOR PLUNGER, MEANS FOR SELECTIVELY LOCKING AND UNLOCKING SAID SUPPORTING STRUCTURE RELATIVELY TO SAID DIAL INDICATOR HOLDER FOR SELECTIVELY PREVENTING AND PERMITTING RELATIVE ROTATION THEREBETEEN FOR SELECTIVELY MEASURING WORKPIECE BORE DIAMETER AND CONCENTRICITY RESPECTIVELY, AND MEANS CONNECTED BETWEEN SAID SUPPORTING STRUCTURE AND SAID DIAL INDICATOR HOLDER FOR RETAINING SAID DIAL INDICATOR HOLDER IN CONNECTED RELATIONSHIP WITH SAID SUPPORTING STRUCTURE AGAINST RELATIVE AXIAL MOTION THEREBETWEEN IN THE UNLOCKED POSITION OF SAID LOCKING MEANS.