Abstract: A corona discharging device in an electrophotographic apparatus used for discharging or uniformly charging the surface of a latent image bearing member. This discharging device has corona wires to which a voltage of a predetermined polarity is applied and corona wires to which a voltage of the opposite polarity to the predetermined polarity is applied, and alternately applies corona discharges to the image bearing member. Grids are provided between the corona wires and the image bearing member and a common bias voltage is applied to the grids. The final surface potential of the latent image bearing member approaches the grid bias potential.

Abstract: This specification discloses a method of making the grid of a corona discharger device and a method of mounting the corona discharger device on an apparatus body, and more particularly a method of easily forming a number of grids and a method of mounting a corona discharger device having such grids on an apparatus body. The grid making method of the present invention comprises winding an electrically conductive thin wire on a rotatable body, fixing the wound thin wire in the direction of the rotational axis of the rotatable body, fixing the wound thin wire in the direction of the rotational axis of the rotatable body by means of fixing members, and cutting the thin wire in the direction of the rotational axis.

Abstract: An electrophotographic process of this invention is achieved by subjecting a photosensitive screen to a matched performance of voltage applications and image irradiation to form a primary electrostatic latent image for modulating the flow of corona ions to enable a secondary electrostatic latent image on a recording member disposed in close proximity to the screen bearing the primary electrostatic latent image.

Abstract: A novel image forming method comprises the steps of providing a thin layer of magnetic developer particles on the surface of a developer supporting member, imagewise applying ions onto the thin layer in the presence of a magnetic field and imagewise transferring the developer particles onto the surface of another member.

Abstract: An electrophotographic process of this invention is achieved by subjecting a photosensitive screen to a matched performance of voltage applications and image irradiation to form a primary electrostatic latent image for modulating the flow of corona ions to enable a secondary electrostatic latent image on a recording member disposed in close proximity to the screen bearing the primary electrostatic latent image.

Abstract: The present invention relates to an electrostatic charging process for uniformly charging an image holding member such as a photoconductive or insulating drum. In an image forming apparatus in which such image holding member is driven both at a first speed and at a second speed different from said first speed, there results a phenomenon of uneven charging due to the difference between the start-up characteristic of charging performance of the charging means and the actual speed at the speed change-over of the image holding member. This drawback is prevented by the present invention in which the speed change-over time of the image holding member is selected different from the charging start time of the charging means in such a manner that the charging is initiated after the speed change-over.

Abstract: In an image formation method of forming an image by modulating an ion flow or charged particles with the aid of a screen having a number of fine passage openings, at least one of the screen and an image reception member is of arcuate cross-section at the modulating position and an image is formed on the screen. One of the screen and the image reception member which is greater in radius is rotated or moved at a higher velocity than the other, thereby modulating the image onto the image reception member.

Abstract: An electrophotographic process of this invention is achieved by subjecting a photosensitive screen to a matched performance of voltage applications and image irradiation to form a primary electrostatic latent image for modulating the flow of corona ions to enable a secondary electrostatic latent image on a recording member disposed in close proximity to the screen bearing the primary electrostatic latent image.

Abstract: In a method of image formation, a primary electrostatic latent image is formed on a screen having a number of fine openings, the primary electrostatic latent image is used to modulate a flow of ions to thereby form a secondary electrostatic latent image on a recording medium, the secondary electrostatic latent image is developed by the use of a developer, the developed image is transferred to another recording member, the charging polarity of the residual portion of the developer remaining on the recording medium is controlled so that, at a position whereat the recording medium and the screen come close to each other, the residual developer may be subjected to a force directed toward the recording medium by an electric field present between the recording medium and the screen, and thereafter the recording medium is reused.

Abstract: This specification discloses an electrophotographic process for forming an electrostatic latent image on a photosensitive medium which may consist of an insulative layer and a photoconductive layer (and further an insulative layer), and also discloses an apparatus for carrying out the process. The electrophotographic process essentially comprises the primary charging step of uniformly charging the insulative layer of the photosensitive medium, and the step of contacting a liquid with said insulative layer and applying a desired voltage to the liquid to thereby discharge or charge the liquid and substantially simultaneously therewith, applying light from an object image to the photoconductive layer of the photosensitive medium. The process may further comprise other various steps as required in electrophotography, such as overall or blanket exposure, development, image transfer and cleaning of the photosensitive medium.

Abstract: Disclosed is an image forming apparatus of a type, in which there is provided first and second electrically chargeable members, a first processing device to form a primary electrostatic latent image on the first chargeable member, a second processing device to form a secondary electrostatic latent image of the second chargeable member in accordance with the primary electrostatic latent image, to develop the secondary electrostatic latent image, and to transfer the thus developed image onto an image transfer material. A detecting device is provided to detect the visible image forming capability of at least one of electrostatic latent images; and, a control device is provided, responsive to the detecting device, to control at least one of the first and second processing devices so as to form a developed image of a predetermined image density.

Abstract: In a device for developing electrostatic images with developer mix including magnetic carrier particles and triboelectrically charged toner particles which comprises a container for the developer mix, magnetic field producing means and an applicator enclosing the magnetic field producing means, a magnetic brush forming means is provided in the container for applying toner particles substantially uniformly to a surface to be developed, and a toner powder-cloud forming means is provided in spaced apart relationship with the magnetic brush forming means for applying toner particles to the same surface by the use of the edge effect of the toner powder.

Abstract: This invention provides an electrophotographic process for forming an image using a photosensitive screen having a plurality of fine openings. The screen has a conductive material on which a photoconductive material is provided, wherein at least a part of the conductive material remains exposed. The peripheries of the openings of the screen are capable of retaining charges as a result of an image exposure to form a primary electrostatic latent image on the screen.

Abstract: The present invention aims at improvement in the image forming method, wherein ion current is modulated in an image form, on the basis of which a secondary electrostatic latent image is formed on a recording sheet, an insulated drum, and other recording media, and the thus formed electrostatic latent image is developed. In more detail, the entire region of such sheet and drum where such secondary electrostatic latent image is formed is uniformly charged beforehand to a desired potential, whereby the fogging phenomenon to occur at the time of development, and changes in the formed image which take place due to variations in the modulating quantity of the ion current on account of deterioration in an ion current modulating element can be prevented. Setting of the member to form thereon such secondary electrostatic latent image at a desired arbitrary potential can be done by, for example, varying the voltage to be applied to a grid provided in a corona discharger.

Abstract: In an electrophotographic method wherein a photosensitive screen having a multitude of tiny openings and formed by the use of a photoconductive member is used to form a primary electrostatic latent image thereon and a corona ion flow from a corona discharger is modulated by the primary electrostatic latent image to form a secondary electrostatic latent image on an electrically chargeable member, an acceleration field having a voltage Ve applied between the screen and the chargeable member is set to a range which satisfies the relation that (Ve-Vs)/d>500[V/mm], where d is the distance between the screen and the chargeable member, and Vs is the maximum potential of the secondary electrostatic latent image formed on the chargeable member.

Abstract: In an electrophotographic method using a screen-like photosensitive medium having a number of fine openings to effect image formation, an air stream directed toward corona discharge means is maintained in the openings of the screen-like photosensitive medium when the corona discharge means, at least during the process of latent image formation, is in operation.

Abstract: In an electrophotographic copying machine of the type which transfers an electrostatic latent image formed on a photosensitive element, usually comprising a conductive base and a photoconductive layer thereon, onto a recording member, an electric dust collector is provided to clean the air flowing in the vicinity of a corona discharger and the photosensitive member. In order to direct the dust-free air, there is provided an air flow passage and a blower such as a fan. The corona discharger and the electric dust collector may be constructed integrally or separately. All of the air in the copying machine may be made dust-free.

Abstract: An electrophotographic method by the use of a photosensitive screen having a number of tiny openings therein and by modulation of corona ion current, wherein a primary electrostatic latent image is first formed on the screen by application of electrostatic charge in conformity to an original image to be reproduced, thus a secondary electrostatic latent image is formed by modulating corona ion current for a plurality of times by the use of one and the same primary electrostatic latent image, and applying to the screen, alternately with the corona ion modulation, a corona ion current of a polarity capable of eliminating the charge polarity of the modulating corona ion current.

Abstract: In an image formation method comprising introducing gases into a gap portion defined by and between two anode and cathode electrodes, and irradiating the gases with a radiation to thereby form an electrostatic latent image on a recording medium disposed in the gap portion, at least one of the electrodes is intended to provide concentric circular potential variations to cause an electric field acting between the electrodes to be varied along the direction of application of the radiation.

Abstract: This invention provides an electrophotographic process for forming an image using a photosensitive screen having a plurality of fine openings. The screen has a conductive material on which a photoconductive material is provided, wherein at least a part of the conductive material remains exposed. The peripheries of the openings of the screen are capable of retaining charges as a result of an image exposure to form a primary electrostatic latent image on the screen.