Locking means

Claim 1

IN A CYLINDER LOCK, THE COMBINATION COMPRISING, A CASING, AN OUTPUT SLEEVE ROTATABLY MOUNTED WITHIN THE CASING, A PLUG ROTATABLY MOUNTED WITHIN THE SLEEVE, SAID PLUG AND SAID CASING HAVING RADIAL RECESSES AND SAID SLEEVE HAVING A SLOT ALIGNABLE IN A PREDETERMINED POSITION OF THE PLUG AND OF THE SLEEVE RELATIVE TO THE CASING, A PAIR OF SEPARATE SIDE LOCKING BAR MEMBERS RECEIVED FOR MOVEMENT RADIALLY WITHIN SAID RECESSES AND SLOT, SAID MEMBERS BEING ARRANGED ONE RADIALLY OVERLYING THE OTHER WITHIN THE RECESSES AND SLOT AND HAVING PORTIONS DEFINING A PARTING FACE BETWEEN SAID MEMBERS, AND KEY-OPERATED TUMBLER MEANS MOUNTED WITHIN SAID PLUG FOR MVOEMENT THEREIN BETWEEN LOCKING AND UNLOCKING POSITIONS TRANSVERSELY OF THE PATH OF MOVEMENT OF SAID MEMBERS, SAID TUMBLER MEANS IN THE LOCKING POSITION THEREOF LOCATING THE RADIALLY INNER OF SAID MEMBERS WHOLLY WITHIN THE PLUG AND THE RADIALLY OUTER OF SAID MEMBERS WITHIN THE SLEEVE AND THE CASING IN POSITIONS ALIGNING SAID PARTING FACE WITH THE CIRCUMFERENTIAL INTERFACE BETWEEN THE PLUG AND THE SLEEVE WHEREBY THE SLEEVE AND THE CASING ARE KEYED TOGETHER AND THE PLUG IS FREELY ROTATABLE WITHIN THE SLEEVE, SAID TUMBLER MEANS IN THE UNLOCKING POSITION THEREOF LOCATING SAID MEMBERS IN AN UNLOCKING POSITION WITHIN SAID RECESSES AND SLOT WHEREIN THE PLUG AND SLEEVE ARE KEYED TOGETHER AND FREELY ROTATABLE WITHIN THE CASING.