Chuck of draw-down type

Claim 1

IN A CHUCK, THE COMBINATION OF A BODY WITH FRONT AND REAR ENDS AND A CENTRAL AXIS, SAID BODY HAVING A FIRST INNER SURFACE DEFINING A CENTRAL ANNULAR RECESS OPEN AT THE REAR BODY END, OTHER INNER SURFACES DEFINING SECOND ANGULARLY-SPACED ANNULAR RECESSES OPEN AT THE FRONT BODY END WITH THEIR AXES BEING INCLINED TO SAID CENTRAL AXIS INWARDLY TOWARD THE REAR BODY END AND EXTENDING IN PLANES, RESPECTIVELY, RADIATING FROM SAID CENTRAL AXIS, AN ANNULAR GROOVE IN SAID FIRST SURFACE INTERMEDIATE ITS ENDS TRAVERSING SAID SECOND RECESSES, AND THIRD ANGULARLY-SPACED RECESSES IN SAID FIRST SURFACE BETWEN AND OPEN AT THE REAR BODY END AND SAID GROOVE AND BEING ALIGNED WITH AND ALSO OPEN TO SAID SECOND RECESSES; A BAR-TYPE JAW ACTUATOR HAVING A JOURNAL FIT, AND BEING RECIPROCABLE, IN SAID CENTRAL RECESS AND HAVING INTERMEDIATE ITS ENDS OUTWARDLY PROJECTING LUGS SPACED THE SAME AS SAID SECOND RECESSES; AND BAR-TYPE JAW CARRIERS HAVING A SLIDING FIT, AND BEING RECIPROCABLE, IN SAID SECOND RECESSES, RESPECTIVELY, AND HAVING TRANSVERSE GROOVES IN REGISTER WITH SAID ANNULAR GROOVE IN FIRST JAW-OPEN POSITIONS OF SAID CARRIERS, SAID ACTUATOR BEING INTRODUCED IN SAID CENTRAL RECESS THROUGH THE REAR BODY END WITH THE LUGS THEREON PASSING THROUGH SAID THIRD RECESSES, WITH SAID ACTUATOR BEING IN SAID FIRST CARRIER POSITIONS TURNABLE WITH ITS LUGS IN SAID ANNULAR GROOVE INTO AND FROM INTERLOCK WITH SAID CARRIER GROOVES, AND SAID CARRIERS BEING ON OPERATIONAL RECIPROCATION OF SAID ACTUATOR RECIPROCATED BY THE LATTER BETWEEN SAID FIRST POSITIONS AND REARWARD JAW-CLOSING POSITIONS THEREOF, WITH SAID ACTUATOR LUGS THEN RECIPROCATING IN SAID THIRD RECESSES AND ANNULAR GROOVE WHILE IN INTERLOCK WITH SAID CARRIER GROOVES.