Pick-Resistant Lock Cylinder Using Torque Resistance

A pick-resistant pin tumbler lock cylinder, comprising:

• a cylinder assembly;
• a plug assembly rotatably disposed in the cylinder assembly and defining a plug axis and a keyway;
• a plurality of key followers moveably disposed in a predetermined array in the plug assembly and transverse to the plug axis;
• a plurality of cylinder pins moveably disposed in the cylinder assembly and being operatively associated with the key followers;
• the cylinder pins being normally biased into engagement with corresponding key followers so that at least one of the cylinder pins is disposed across a shear line defined by the intersection of the plug assembly with the cylinder assembly thereby preventing rotation of the plug assembly in the cylinder assembly;
• said at least one of the cylinder pins being moved above the shear line upon insertion of a valid key in the keyway, thereby permitting rotation of the plug assembly in the cylinder assembly;
• wherein an attacker being able to insert a first tool into the keyway to apply a threshold rotational torque to the plug assembly, and further being able to insert a second tool into the keyway to sense the relationship of said at least one cylinder pin to the shear line during application of the threshold torque;
• and further comprising:
• a torque augmenter operatively associated with the cylinder assembly and the plug assembly to increase the threshold torque required to rotate the plug assembly in the cylinder assembly thereby hampering the attacker's ability to sense the relationship of said at least one cylinder pin to the shear line by manipulating said first and second tools.