Abstract: A noncontact seal for a donor roll in an electrophotographic printing machine. The seal is fixed in the developer housing and envelopes each end of the donor roll but does not contact the donor roll. The small space does not allow a positive airflow sufficient to cause toner particles to be emited from the developer housing so as to contaminate the other portions of the printing machine. The seal is made of a low friction material such as DELRIN.RTM. so that toner particles do not stick to the seal and cause a buildup that would be detrimental to the photoreceptive member.

Abstract: A sensing system is disclosed for detecting a full condition within a waste developer system, the sensing system including: a developer waste bottle for receiving and holding waste developer material including toner and carrier deposited therein from the developer system, the developer waste bottle having a translucent, removable viewing window for optical viewing the level of developer material therein, the viewing window comprises a sensing portion in fluid communication with the developer waste bottle, the sensing portion adapted to have developer material flow therein when the magnetic material in the toner waste bottle reaches the predetermined level.

Abstract: A channel for recirculating a stream of air located adjacent a stream of marking particles exiting substantially tangentially from a marking particle transport member within a developer unit is provided. The stream of marking particles defines an inner boundary thereof extending tangentially from a first position adjacent to the transport member and defines an outer boundary thereof spaced from the transport member and the inner boundary. The channel includes a first member positioned outside the stream of marking particles. At least a portion of the first member is positioned substantially adjacent the outer boundary of the stream of marking particles and is spaced from the transport member. The channel also includes a second member connected to the first member and a third member connected to the second member. The second member is positioned adjacent the transport member and is spaced from the stream of marking particles.