Folding rotor blade

Claim 1

A JOINT FOR ATTACHING AND FOLDING A ROTOR BLADE RELATIVE TO THE ROTOR HUB, SAID JOINT COMPRISING: A BIFURCATED BLADE ROOT FITTING FOR RECEIVING AND HOLDING THE BLADE AT THE BIFURCATED END; PLURAL SETS OF SPACED EARS ON THE OTHER END OF SAID FITTING; A HUB CUFF MEMBER ATTACHED TO THE ROTOR HUB AT ONE END; PLURAL SETS OF SPACED EARS ON THE OTHER END OF SAID CUFF MEMBER; SAID SETS OF EARS ON THE CUFF MEMBER BEING COMPLEMENTARY TO THE SETS OF EARS ON THE FITTING AND INTERLOCKING THEREWITH; A CYLINDRICAL OPENING IN EACH SET OF INTERLOCKED EARS; A BOLT ASSEMBLY FITTING INTO EACH OF SAID OPENINGS AND COMPRISING A HEADED TAPER BOLT AND A MATING SPLIT TAPER SLEEVE KEYED TO SAID BOLT, SAID BOLT HAVING A THREADED END EXTENDING BEYOND SAID SLEEVE; SAID END HAVING A LARGER DIAMETER THAN THE SMALLEST INSIDE DIAMETER OF THE SLEEVE; NUT MEANS FOR ENGAGING SAID THREADED END AND SECURING THE BOLT ASSEMBLIES IN SAID OPENINGS FOR ATTACHING SAID BLADE TO THE CUFF MEMBER; AND A DEVICE FOR INTERLOCKING THE BOLT ASSEMBLIES TO PREVENT BLADE FOLDING UNTIL ALL BOLT ASSEMBLIES ARE LOOSENED, SAID DEVICE BEING PIVOTALLY MOUNTED BETWEEN THE BOLT HEADS AND HAVING HOOK-SHAPED ARMS ADAPTED TO ENGAGE THE BOLT HEADS AND A PROJECTION ON THE HOOKED PORTION OF SAID ARMS ADAPTED TO FIT UNDER THE BOLT HEADS AND TO LIE OVER A PORTION OF THE SLEEVE END WHEN THE ARMS ARE ENGAGED WITH THE BOLT HEADS.