Patent ID: 8672470

Claim:
A life sensing method for use with a drum maintenance unit of an imaging device, the method comprising: detecting a media area and an inked area of the media area for each print made by an imaging device; incrementing a total media area value and a total inked area value with reference to the detected media area and the detected inked area for each print made by the imaging device; monitoring a release agent level in a drum maintenance unit (DMU) reservoir with a float level sensor to detect a “low level” condition in DMU reservoir by detecting a buoyant member of the float level sensor pivotably mounted to a proboscis extending from an end cap of the DMU reservoir moving to a predetermined position within the DMU reservoir; decrementing, in response to the float level sensor not detecting a “low level” condition, a predetermined mass from a current mass for release agent in the DMU reservoir using a default oil coverage rate for each print made by the imaging device; and decrementing, in response to the float level sensor detecting a “low level” condition, a mass from the current mass for the DMU reservoir using a refined oil coverage rate for each print made by the imaging device, the refined oil coverage rate being calculated with reference to the total media area value and the total inked area value.