Browse Prior Art Database

Original Publication Date: 1985-Apr-30
Included in the Prior Art Database: 2004-Apr-04

Publishing Venue

Xerox Disclosure Journal


In a two cycle electrostatographic reproducing machine wherein the developer housing may function to both develop the electrostatic latent image on the photoreceptor as well as clean residual toner remaining on the photoreceptor after the toner image has been transferred to a copy sheet it is generally desired to collect toner that has been cleaned from the imaging surface since this toner is generally of wrong sign and may adversely effect the life of the developer charge. The figure illustrates a convenient manner in which this may be done. Developer housing 20 comprises two magnetic brush rolls 22 and 24 in developing engagement with a photoreceptor belt 26. The toner is delivered to the housing through means of delivery system 28 and admixed and conveyed to the magnetic brush developer rolls by means of cross mixer admixer 30. During the development cycle cleaning blade 32 is cammed out of contact with the photoreceptor 26 so that development of the electrostatic latent image on the belt 26 may be accomplished by means of the developer rolls 22 and 24. During the second cycle the cleaning blade 32 is moved into cleaning engagement with the photoreceptor belt 26 and the untransferred toner is scrapped into collector pan 34 which is attached to the developer housing. The collector pan 34 has a spill over opening 36 at its top which is in communication with the top of the developer housing 20. The capacity of the toner collection enclosure 34, if desired, may be designed to contain an amount of residual toner collected up to the toner spill over opening at the top that is about equal to the amount of toner collected when the carrier in the developer housing 20 has reached its maximum functional life and failure occurs in that the triboelectric relationship between carrier and toner deteriorates as a result of the carrier becoming coated with toner producing inadequately charged toner and therefore poor copies.