Lock cylinder with electronic key recognition

A method of operating a lock cylinder including a plug, a tailpiece positioned at a distal end of the plug, a plurality of key followers seated in the plug, a sensor assembly including a plurality of sensors, and an electronic lock operable to selectively prevent the plug from rotating the tailpiece, wherein each of the key followers includes a sensor interface and has a variable transverse position, and wherein each of the sensors has a sensing region, the method comprising:

• associating each of the key followers with a corresponding one of the sensors, wherein the associating includes forming an associative link between the sensor interface of the key follower and the sensing region of the corresponding sensor;
• generating an output signal set with the sensor assembly, wherein the output signal set includes a plurality of output signals, wherein each of the output signals is generated by a corresponding one of the sensors, wherein each of the output signals varies in response to transverse movement of the corresponding key follower as a result of the associative link;
• determining an event, wherein the event is one of a key insertion event and a tampering event, and wherein the determining includes comparing the output signal set with one or more criteria indicative of the key insertion event and/or the tampering event;
• in response to the key insertion event, generating a key profile based upon the output signal set, and comparing the generated key profile with authorization data including at least one reference key profile;
• selecting an action in response to the determined one of the events, wherein the action is selected from a plurality of actions, the plurality of actions including an unlocking action and a reporting action;
• wherein selecting the action in response to the key insertion event includes selecting one of the plurality of actions based upon the comparison of the generated key profile with the authorization data;
• and
• wherein selecting the action in response to the tampering event includes selecting the reporting action;
• and
• performing the selected action;
• wherein performing the unlocking action includes moving the electronic lock from a locking state in which the electronic lock prevents the plug from rotating the tailpiece to an unlocking state in which the electronic lock does not prevent the plug from rotating the tailpiece;
• and
• wherein performing the reporting action includes generating reporting information relating to an unauthorized attempt to operate the lock cylinder.

A lock cylinder, comprising:

• a plug rotatably mounted in the shell, the plug including:
• a longitudinally extending keyway;
• a longitudinal channel, wherein the longitudinal channel is offset from the keyway in a first lateral direction;
• and
• a plurality of plug tumbler shafts, wherein each of the plug tumbler shafts includes:
• a transverse portion extending transversely from the keyway;
• and
• a lateral channel extending from the transverse portion to the longitudinal channel;
• a plurality of key followers, wherein each key follower is seated in a corresponding one of the plug tumbler shafts and includes:
• a body portion received in the transverse portion of the corresponding plug tumbler shaft, the body portion including an engagement surface structured to engage the edge cut of the key;
• a lateral arm extending laterally from the body portion, wherein the lateral arm is received in the lateral channel of the corresponding plug tumbler shaft;
• and
• an optical patch mounted on the lateral arm, wherein the optical patch faces the longitudinal channel;
• a sensor assembly including at least one optical sensor seated in the longitudinal channel;
• a controller in communication with the sensor assembly;
• a tailpiece extending from a distal end of the plug;
• and
• a locking assembly structured to selectively prevent the plug from rotating the tailpiece;
• wherein the key followers are structured to align the optical patches when a correct key is inserted in the keyway;
• wherein the sensor assembly is structured to generate an alignment signal in response to alignment of the optical patches;
• and
• wherein the controller is structured to generate an unlock signal in response to the alignment signal.