Abstract: Improved dual belt synchronization for a print engine for color electrophotography using a photoreceptor belt and a seamless transfer belt on which a composite image is built up. Improved synchronization of the two belt drives enhances image registration. A tension mechanism used in conjunction with the belts prevents rapid changes in the belt dimensions. An improved transfer belt cleaner system is synchronized with the belt drives such that excess toner is not left in the imaging area of the transfer belt.

Abstract: An apparatus which measures the electrical current biasing a developer roller and transmits a control signal corresponding thereto to control discharging of marking particles in a development system of an electrophotographic printing machine. At selected intervals, the control signal is adjusted as a function of the measured mass to area ratio of the marking particles deposited on a test area recorded on the photoconductive member.

Abstract: A device for removing residual particles from a photoconductive member comprises a fur brush in contact with the photoconductive member, a metal roller in contact with the fur brush, and a scraper blade in contact with the metal roller. The fur brush is maintained at a first biasing voltage, e.g., +50V, while the metal roller is maintained at a second biasing voltage which is of the same polarity but greater in magnitude than the first biasing voltage, e.g., +150V. The fur brush attracts residual particles from the photoconductive member while the metal roller attracts residual particles from the fur brush. The scraper blade scrapes the residual particles from the metal roller, the particles falling into a conveying auger for recycling.

Abstract: A transfer material separating device for separating a transfer material from a surface of an image bearing member after an image formed on the image bearing member is electrostatically transferred onto a transfer material at a transfer station includes a separating electrode, disposed downstream of the transfer station with respect to movement direction of the transfer material, for causing electric discharge between the transfer material and the separating electrode, and a moisture absorbable member disposed adjacent the separating electrode and electrically isolated, the moisture absorbable member being capable of absorbing moisture and having an electric resistance which changes with moisture absorbed thereby.

Abstract: A thermal reed switch assembly including two magnetic reed switches having two permanent magnets and at least two semicylindrical thermal magnetic members each having mutually different magnetic tansition points sandwiching the reed switch therebetween. An inner diameter of one thermal magnetic member may be larger than at least a second member therein increasing the sectional area ratio of the members.

Abstract: A safety electrical receptacle cover plate for dual socket wall receptacles has rotatable shutters adapted for receiving the prongs of a plug, but is normally biased by non-conducting resilient members to close registery with the slots of the socket members. The shutters are received in recesses formed in the rear of the plate, have central portions disposed through openings extending through the plate, and have stepped outer portions journalled in the recesses. A pair of oppositely disposed arms are formed on the outer portions and carry members about which resilient bands are disposed for urging the shutters out of the positions of registery. The periphery of the cover plate has a lip about which a resiliently compressible material is disposed so that when the plate is secured to a receptacle the plate is adjustably located relative to the wall to permit the shutters to abut the face of the sockets thereby ensuring proper electrical contact of the plug prongs with the sockets.