Patent ID: 7963135

Claim:
A pin tumbler lock comprising: a shell; a plug rotatably positioned in the shell, the plug defining a keyway and at least one bore positioned along and extending away from the keyway; and a sidebar mounted on the plug, the sidebar engaging the shell to prevent rotation of the plug in the shell and being movable into the plug to permit the plug to be rotated in the shell; a bottom pin positioned in the bore and being slidable with respect to the bore, the bottom pin having a contact surface oriented toward the keyway for contacting a key inserted into the keyway, the bottom pin having a channel formed thereon for receiving a portion of the sidebar to permit movement of the sidebar out of engagement with the shell to permit rotation of the plug in the shell; and means on the bottom pin for obstructing movement of the pin along the bore when a portion of the sidebar is extended into the channel of the pin prior to insertion of a key into the keyway to raise the pin in the bore; wherein the means for obstructing comprises a protrusion of the surface of the pin into the channel of the pin.