Positive release pin-type clamp

Claim 1

AN AXIAL, PIN TYPE CLAMP FOR TEMPORARILY HOLDING A PLURALITY OF APERTURED WORK PIECES IN ASSEMBLED RELATION WITH THE APERTURES IN ALIGNMENT, COMPRISING: AN ELONGATE GENERALLY HOLLOW CASING HAVING A SUBSTANTIALLY CLOSED FORWARD END ADAPTED FOR CLAMPING ENGAGEMENT WITH A WORK PIECE AND FORMED WITH AN AXIAL PASSAGE THERETHROUGH, AND HAVING AN INTURNED FLANGE AT ITS AFT END TO PROVIDE WITHIN SAID AFT END AN AXIALLY EXTENDING ANNULAR RECESS HAVING A SMOOTH INNER SURFACE; A RETAINER MEMBER SLIDABLY AND NON-ROTATABLY MOUNTED IN SAID CASING; SAID RETAINER MEMBER HAVING A BASE SLIDABLE WITHIN SAID CASING, A GRIPPER EXTENDING THROUGH THE PASSAGE AT THE FORWARD END, AND A DRIVE SHANK EXTENDING THROUGH THE AFT END, THE SHANK BEING AT LEAST PARTLY THREADED; AND A DRIVE NUT MOUNTED FOR LIMITED AXIAL MOVEMENT HAVING A THREADED BORE FOR ENGAGEMENT WITH THE THREADED PORTION OF THE SHANK TO MOVE THE RETAINER MEMBER AXIALLY; SAID LIMITED AXIAL, SLIDABLE, MOVEMENT OF SAID NUT HAVING AN EXTENT EQUAL TO THE ADVANCE OF A PLURALITY OF SAID THREADS SO THAT THE NUT WILL RE-ENGAGE A PLURALITY OF THREADS ON THE DRIVE SHANK BEFORE ASSUMING THE LOAD OF RETRACTING THE RETAINER MEMBER; SAID NUT HAVING AN AFT TOOL ENGAGING PORTION AND A FORWARD PORTION OF REDUCED DIAMETER TERMINATING IN AN OUTWARD FLANGE AT ITS FORWARD END, SAID SECOND FLANGE BEING LOCATED IN SAID RECESS IN THE CASING FOR SLIDING AXIAL MOVEMENT AND ROTATABLE MOVEMENT; THE FLANGES SERVING AS ABUTMENTS TO PREVENT SEPARATION OF THE DRIVE NUT FROM THE CASING AND TO TAKE THE THRUST FORCE OF THE NUT; SAID GRIPPER HAVING A HEADED FREE END AND BEING COLLAPSIBLE UPON FORWARD EXTENSION TO PASS THROUGH THE APERTURES IN THE WORK PIECE ASSEMBLY, AND EXPANDABLE LATERALLY UPON REARWARD RETRACTION TO TIGHTLY ENGAGE THE WALLS OF THE APERTURES AND TO CAUSE THE HEADED FREE END TO ENGAGE THE REMOTE SURFACE OF THE ASSEMBLY TO GRIP THE LATTER BETWEEN THE HEADED FREE END AND THE FORWARD END OF THE CASING; SAID DRIVE NUT ACTING TO FORCEFULLY AND POSITIVELY MOVE SAID GRIPPER INTO AND OUT OF BINDING ENGAGEMENT WITH THE WALLS OF SAID APERTURE AND SAID HEADED FREE END INTO AND OUT OF CLAMPING ENGAGEMENT WITH THE ASSEMBLY.