Patent ID: 7377140

Claim:
A lock comprising: a body; a latch bolt mounted in the body; a wheel pivotally mounted in the body and operable to retract the latch bolt from an extended position to a retracted position, the wheel including a through-hole defined by a circumferential wall; an outside spindle adapted to be mounted to an outside handle, the outside spindle including a front end having an extension, the extension being not in contact with the circumferential wall of the through-hole of the wheel; a spring mounted in the outside handle for biasing the front end of the outside spindle into the through-hole of the first wheel, allowing joint rotation of the wheel and the outside spindle; a locking plug mounted in the body and movable between an unblocking position allowing retraction operation of the latch bolt and a blocking position not allowing retraction operation of the latch bolt; and a push member mounted on the locking plug; wherein when the locking plug is in the unblocking position, the front end of the outside spindle is engaged with the wheel to allow joint rotation of the outside spindle and the wheel; and wherein when the locking plug is moved from the unblocking position to the blocking position, movement of the push member pushes the front end of the outside spindle away from the through-hole of the wheel such that the front end of the outside spindle is disengaged from the circumferential wall of the through-hole of the wheel, thereby disengaging the outside spindle from the wheel.