Patent ID: 6148157
Filing Date: 2000-11-14
Classification: G03G

Abstract:
An apparatus for developing a latent image recorded on a surface, comprising:a housing defining a chamber storing a supply of developer material comprising toner;a toner donor member spaced from the surface and being adapted to transport toner to a region opposed from the surface;means for conveying said developer material in the chamber of said housing onto said donor member;an electrode member spaced near the surface of a donor roll, said electrode member; a power supply electrically biasing said electrode member to detach toner from said donor member as to form a toner cloud for developing the latent image; anda current signature analysis system, in communication with said power supply, for sampling the current signature going through said electrode member; anda comparator, in communication with said current signature analysis system, for comparing said current signature to a plurality of preset fault signatures, said comparator including means for generating a message fault, said generating means generates said message fault if the difference between said instant current signature to said plurality of preset fault signatures exceed a preset threshold value.