Anti-probe device for key locks

Claim 1

A PROTECTIVE DEVICE FOR A KEY ACTUATED LOCK HAVING A LOCK BODY, AND A HEAD PORTION INCLUDING A KEYHOLE FOR RECEIVING A SHANK AND AN ADJACENT ACTUATING HEAD OF A KEY WHOSE HEAD IS LARGER THAN THE SHANK THEREOF, SAID DEVICE COMPRISING A HOLLOW SHEILD MEMBER FOR SUBSTANTIALLY COVERING THE HEAD PORTION OF THE LOCK, SAID SHIELD MEMBER HAVING A FORWARD WALL APERTURED FOR RECEIVING A PORTION OF A KEY, SAID FORWARD WALL AND APERTURED BEING SPACED FROM THE HEAD PORTION AND THE KEYHOLE THEREIN TO PROVIDE A CHAMBER INTERMEDIATE SAID FORWARD WALL AND SAID HEAD PORTION, TO INTERFERE WITH UNAUTHORIZED PROBING OF THE LOCK THROUGH THE KEYHOLE THEREOF, THE APERTURE OF THE FORWARD WALL OF THE SHIELD COMPRISING AN ENLARGED PORTION LARGER THAN THE SHANK AND THE ACTUATING HEAD OF THE KEY, AND A NARROW CONNECTING SLOT PROJECTING FROM SAID ENLARGED PORTION, SAID SLOT BEING LARGER THAN THE KEY SHANK, SMALLER THAN THE ACTUATING HEAD OF THE KEY, AND SMALLER THAN THE KEYHOLE OF THE LOCK, WHEREBY SAID NARROW SLOT BLOCKS A PORTION OF THE LOCK KEYHOLE; THE ENLARGED PORTION OF THE SHIELD APERTURE BEING OFFSET AS TO ALIGNED RELATIVE TEO THE KEYHOLE OF THE LOCK, AND A PORTION OF THE NARROW CONNECTING SLOT BEING ALIGNMENT WITH SAID LOCK KEYHOLE, WHEREBY ALIGNMENT OF THE KEY HEAD FOR INSERTION THEREOF INTO THE KEYHOLE OF THE LOCK NECESSITATES AN INITIAL INSERTION OF THE KEY HEAD THROUGH THE ENLARGED PORTION OF THE SHIELD APERTURE, FOLLOWED BY LATERAL BODILY SHIFTING OF THE KEY FOR PLACING THE SHANK THEREOF WITHIN THE NARROW CONNECTING SLOT OF THE SHIELD APERTURE AND IN ALIGNMENT WITH THE KEYHOLE OF THE LOCK; AND MEANS FIXING THE SHIELD MEMBER RELATIVE TO THE KEYHOLE OF THE LOCK TO PREVENT UNAUTHORIZED ACCESS TO SAID KEYHOLE.