a lock employing a lock cylinder protected by an outer escutcheon and positioned coaxially with a lock control mechanism and an inner doorknob . an outer doorknob is supported by the outer escutcheon and mounted on an axis which is offset with respect to the axis of the lock cylinder and inner doorknob . a cam and pushrod arrangement is utilized to transfer rotation of the outer knob to the lock mechanism . the encasing of the lock cylinder within the outer escutcheon instead of the outer knob increases the security of the device by making it more difficult to tamper with the lock cylinder . in addition , slight modifications prevent the application of excess torque to the outer knob from releasing the lock mechanism .