Plastic centrifuge bottles and caps therefor

Claim 1

IN COMBINATION, A CENTRIFUGE ROTOR HAVING A PLURALITY OF ANGULARLY DISPOSED CAVITIES, EACH CAVITY HAVING A COUNTER BORE IN ITS UPPER END, A PLASTIC CENTRIFUGE BOTTLE DIMENSIONAL TO FIT A ROTOR CAVITY AND INCLUDING AN EXTERNALLY THREADED NECK DEFINING A SHOULDER, THE OPEN END OF SAID NECK CONSTITUTING AN ANNULAR, OUTWARDLY EXPOSED SEAT;-A JACKET INCLUDING A NECK PORTION THREADED ON SAID BOTTLE NECK AND A SKIRT PORTION OVERLYING THE SHOULDER OF SAID BOTTLE, AND EXTENDING A SHORT DISTANCE BELOW SAID SHOULDER, SAID SKIRT PORTION DIMENSIONED TO FIT A COUNTER BORE, THE NECK PORTION OF SAID JACKET BEING EXTERNALLY THREADED; AND A CAP COMPRISING A RETAINER THREADED ON SAID NECK PORTION AND INCLUDING A CLAMPING PORTION OVERLYING THE MOUTH OF SAID BOTTLE, A CLOSURE INCLUDING A DISC MEMBER OVERLYING SAID MOUTH AND FITTING FREELY WITHIN SAID RETAINER UNDER SAID CLAMPING PORTION, AND AN ANNULAR SEAL OF THE O-RING TYPE CARRIED BY SAID CLOSURE AND SEATED ON SAID SEAT, SAID JACKET NECK PORTION BEING POSITIONED RELATIVE TO SAID SEAT AND THE THREADED CONNECTION BETWEEN SAID JACKET NECK PORTION AND SAID RETAINER BEING OF SUFFICIENT EXTENT TO ENABLE SAID SEAL TO BE COMPRESSED AXIALLY BETWEEN SAID SEAT AND SAID DISC MEMBER BY SAID CLAMPING PORTION AS SAID RETAINER IS SECURED.