Latch bolt operating device having improved shield construction to deter probe manipulation

Claim 1

In a latch construction of the type for mounting in doors and the like with a bolt extendable from a door edge, a latch driving mechanism mounted within the door operably connected to the bolt, exterior and interior operators respectively engaged with exterior and interior faces of the door operably connected to the latch driving mechanism and each operable for moving the bolt between extended and retracted positions through movement of the latch driving mechanism, the exterior operator including a lock cylinder telescoping a lock plug and telescoped by a transversely thickened and hardened metal guard collar, longitudinally reactive abutment means between the lock cylinder and the guard collar for the lock cylinder to retain the guard collar longitudinally inwardly in assembly, fastening means longitudinally between the interior and exterior operators retaining the exterior operator in assembly and through the abutment means the guard collar in assembly; the improvement comprising: a metal shield longitudinally outwardly transversely abutting said guard collar and longitudinally inwardly transversely abutting said door exterior face so that said guard collar is retained in assembly by said lock cylinder and fastening means and said shield is retained in assembly by said guard collar, said shield extending longitudinally inwardly into said door interior at least partially annularly around a portion of said latch driving mechanism shielding said latch driving mechanism portion to deter surreptitious manipulation thereof by penetration through the door exterior face.