Image forming apparatus with variable gap size based on recording media supply level

摘要

Toner is conserved in an image forming apparatus, such as an electrophotographic printer (e.g., laser printer), by varying the interpage gap when approaching an exhaustion of the recording media supply ("paper out"). A supply level sensor is used to determine whether the supply of discrete recording media (e.g., paper sheets) is above or below a predetermined level. A smaller value interpage gap is used when the supply level is above the predetermined level. The interpage gap is automatically lengthened to a second larger value when the sensed media supply level drops below the predetermined level. The longer second interpage gap allows for "paper out condition" that may result from printing of sheet N-1 to be determined prior to image formation beginning for sheet N. The interpage gap may be reset to the smaller value when the supply has been refilled to above the pre-determined level.