Abstract: A modular copier/printer or similar image forming apparatus of the type having an image transfer body in the form of a drum or belt allows documents to be reproduced in a paper discharge mode which discharges paper sheets, or recording media, in page-sequential order. When an automatic two-sided copy mode is selected, the apparatus automatically sets up the page sequential paper discharge mode to a "collation mode" through a minimum number of sorter bins which has been optimally designed to correspond with the shortest two-sided copy loop. Hence, when mixed black-and-white documents and color documents are reproduced together in the automatic copy mode, paper sheets exit the apparatus in the correct page order. As a result of this automatic change in operating modes, fewer "skip" frames need be introduced during the copying operation, thereby enabling the copier to produce multiple collated copies of the multipage document very efficiently.

Abstract: An electrically switchable magnetic brush for use in toner deposition or removal devices used in imaging machines of the electrostatic type. When energized by a multiphase alternating current power source or a brushless direct current power source rotatably mounted drum (9) requires no external driving force and is self-propelled.

Abstract: A liquid electrophotographic development system has a plurality of removable cartridges mounted on a rotatable support for selective engagement with an electrophotographic member to be developed. Each cartridge has a liquid developer reservoir and a flexible toner concentrate container from which concentrate is supplied to the developer in the reservoir as needed. A fluted roll pumps developer in a uniform manner from the reservoir to the electrophotographic member. After depletion of the toner concentrate and developer, any developer remaining in the cartridge can be pumped into the flexible container to prevent spillage on disposal of the cartridge. The cartridge housing has only one opening and minimum-size passages between the reservoir and the opening to inhibit evaporation of developer liquid.