Abstract: An image forming apparatus is provided with a light emitting element for indicating a specific range of an original disposed on an original table, and the other light emitting elements for erasing the electric charge on the surface of a photosensitive body in response to the specific range of the original indicated by the light emitting element. A spot light is applied to the original on the original table by the light emitting element, and moved to specify the perimeter of an erasure range. In image forming, the specific range inside the perimeter is defined by an erasure range designating key and is developed through the black toner by a developing device. On the other side, the specific range outside the perimeter is defined by the other erasure range designating key and is developed through the red toner by the other developing device.

Abstract: Apparatus for adjusting the position of a movable doctor blade structure. The apparatus includes a block member that presents an inclined surface to a contact made with the doctor blade structure. The block member is moved relative to the contact made with the doctor blade structure to alter the position of the doctor blade structure by rotation of a screw that is captively held in a support means and is threaded to the block member.

Abstract: An electrophotographic copying apparatus has an electrically charged toner of one polarity which is transformed from an oppositely electrically charged surface of a photoconductive drum to the front side of a blank sheet where the front side of the blank sheet is intended to be a copy. The back side of the blank sheet engages the outer surface of a transfer drum which is positioned adjacent to the photoconductive drum. The transfer of the toner occurs within a nip defined by the photoconductive drum and the transfer drum. A cam rotates in a timed sequence relative to the transfer drum and with a vacuum pump located adjacent to the transfer drum the cam is in communication with the surface of the transfer drum so that a vacuum is created at the back side of the blank sheet resulting in the blank sheet being held to the surface of the transfer drum by ambient air pressure and the vacuum thus overcoming the electrostatic attraction of the blank sheet to the photoconductive drum.

Abstract: A copy paper supply timing control system includes a slit plate secured to a shaft of a photo-sensitive drum for developing a pulse signal of a period (t') in response to the rotation of the photo-sensitive drum. A copy paper supply system is enabled when a predetermined time has passed after an optical system initiates its movement. The predetermined time is determined by a number (N) of the pulse signals and a time period (T) from the development of the N-th pulse signal. That is, the actual copy paper supply is conducted when (N.times.t'+T) have passed after the optical system initiated its movement. The copy paper supply timing control system includes a compensation system for modifying the pulse number (N) and the time period (T) in response to a detected period (t) between the initiation of the optical system movement and the development of the first pulse signal.

Abstract: A modular developer and cleaner housing for use in an electrostatographic reproducing apparatus of the type wherein a recyclable imaging member completes two cycles for each copy produced, includes a development portion and a cleaning portion with the development portion including means for continuous development engagement with an imaging surface, and the cleaning portion including a cleaning blade for cleaning an imaging surface and including means for alternately positioning the cleaning blade into and out of cleaning engagement with the imaging surface. The cleaning portion further includes a used toner collection enclosure to collect used toner cleaned from the imaging surface by the cleaning blade which is separated from the development portion of the housing whereby toner cleaned from the imaging surface is collected separately from the developer.

Abstract: An assembly for developing a latent electrostatic image formed on the photosensitive outer surface of a rotating developing drum making up a part of an electrophotographic copying apparatus is disclosed herein. This assembly includes a supply of developer contained within a housing adjacent the drum, a series of electrodes acting on the developer to aid in developing the electrostatic image, and an arrangement cooperating with the electrodes for cleaning the latter of developer deposited thereon during the development process.

Abstract: The invention provides an apparatus for forming a multicolor image, comprising a photoconductive drum which comprises a conductive substrate, and a photoconductive layer and a transparent insulating layer, a first charger to perform primary charging, a first light source to expose the entire surface of the photoconductive drum, a second charger to secondarily charge the transparent insulating layer at the second polarity, a second light source to emit light, an amount of which is controlled to have two levels in accordance with first and second color image data, a first developing unit to develop the first color image, a third light source to perform a second entire-surface exposure of the photoconductive drum, and a second developing unit to develop the second color image.