Cylinder lock system

A cylinder lock system comprising:

• a shell having a plurality of pin tumbler receiving chambers, said shell further having an interior surface which defines a core receiving chamber, said pin tumbler receiving chambers extending to said interior surface, said shell being mounted with a fixed orientation in the use environment of said lock;
• a core cooperating with said shell to form the relatively movable component of the lock of said system, said core being disposed within said core receiving chamber of said shell for rotation about an axis, said core defining a longitudinally extending keyway having oppositely disposed sides, said core further defining a plurality of pin tumbler receiving chambers, said core pin tumbler receiving chambers being alignable with said shell pin tumbler receiving chambers, said core pin tumbler receiving chambers extending between said keyway and an exterior surface of said core whereby communication may be established between said shell and core pin tumbler receiving chambers, a shear line for the lock of said system being defined by the interface between said interior surface of said shell and said exterior surface of said core;
• pin tumblers reciprocally disposed in said pin tumbler receiving chambers, said pin tumblers each having at least a bottom pin and a driver pin which are in axial alignment and abutting contact, at least one of said pins of each of said pin tumblers extending across said shear line so as to be partly disposed in an aligned shell pin tumbler receiving chamber and core pin tumbler receiving chamber in the absence of a properly bitted key in said keyway, said pin tumblers each further including a first spring for resiliently biasing said aligned pins in the direction of said core;
• at least first auxiliary locking means for establishing a rotation preventing mechanical coupling between said shell and said core in the absence in said keyway of a key having a first profile feature which cooperates with said first auxiliary locking means, said first auxiliary locking means being carried by and being movable relative to said core, said auxiliary locking means communicating with a first side of said keyway;
• trapping means for mechanically capturing in said keyway keys which lack a second profile feature, said trapping means being carried by and being movable relative to said core, said trapping means extending between said shear line and a second side of said keyway which is oppositely disposed with respect to said first keyway side, said trapping means having an actuating portion which is at least in part in alignment with said first auxiliary locking means, said actuating portion of said trapping means cooperating with a said second profile feature of a key, rotation of said core relative to said shell being permitted by movement of said auxiliary locking means to decouple said core from said shell and rotation of said core to an unlocked orientation being permitted by key second profile feature induced movement of said trapping means to a non-trapping position;
• and
• a key, said key comprising:
• a bow;
• a blade longitudinally extending from said bow and terminating at a blade tip, said blade having first and second spacially displaced side faces and a pair of oppositely disposed and spaced edges which interconnect said side faces, said first and second side faces being at least in part substantially parallel to one another;
• at least a first three dimensional projection extending outwardly from one of said blade side faces, said projection defining said second profile feature, the side of said projection which faces in the direction of said blade tip defining a ramp which extends to the maximum height of said projection whereby said projection can function as a cam in response to longitudinal movement of said blade;
• and
• an indentation in the second of said blade side faces, said indentation being in registration with said projection, said indentation defining said first profile feature.