Abstract: An image forming apparatus including a rotatable developing member having a plurality of developing devices for developing an image bearing member at a first developing station, and a second single developing device arranged upstream of the rotatable developing member for developing the image bearing member exclusively at a second developing station different from the first developing station. The second developing device has a cover portion covering the rotatable developing member, and a portion of the cover portion is disposed at a position spaced apart from a rotation axis of the rotatable developing member by a predetermined length in a horizontal direction away from the image bearing member. The rotatable developing member rotates in an opposite direction with respect to the direction of rotation of the image bearing member to prevent toner from scattering toward the optical system.

Abstract: An image forming apparatus includes a first image bearing member on which a toner image can be formed; an intermediate transfer member onto which the toner image is transferable from the first image bearing member; wherein the toner image is further transferred onto a second image bearing member therefrom; wherein the intermediate transfer member comprises a conductive layer to which a voltage is applied, a surface layer on the conductive layer, and a volume resistivity of the surface layer is 10.sup.5 -10.sup.11 ohm.cm.

Abstract: This invention relates to a color image forming apparatus for forming a color image with dry developer, capable of preventing deterioration of image quality, resulting from contamination of optical components by the non-magnetic developer scattered from the developing unit. For this purpose there are provided, along the moving direction of an image bearing member effecting endless movement, charging means, optical means, first developing means utilizing developer containing a magnetic component, second developing means utilizing non-magnetic developer of a color different from that of the developer of the first developing means, and transfer means maintained in contact with or close to the image bearing member for transferring a developed image from the image bearing member to a recording material such as paper. A space containing the second developing means is enclosed by the shape of the first developing means, transfer means and image bearing member.

Abstract: A developing apparatus includes an image bearing member for bearing an electrostatic image, a developer carrying member, opposed to the image bearing member to form a developing zone therebetween, for carrying a developer to the developing zone to develop an electrostatic latent image on the image bearing member, and oscillating bias means for applying an oscillating bias to the developer carrying member, wherein the oscillating bias includes a constant-current-controlled AC component and a constant-voltage-controlled DC component.

Abstract: An image forming apparatus includes a movable image bearing member; an image forming device for forming an image on the image bearing member; a charging member disposed opposed to the image bearing member; and bias application device for applying a bias voltage to the charging member, wherein the bias applying device effects a constant voltage control to the charging member when an image area of the image bearing member is in a charging region of the charging member, and effects a constant current control during at least a part of a period in which an area of the image bearing member other than the image area is in the charging region, and wherein a level of a constant voltage of the constant voltage control is determined during the constant current control.

Abstract: An image forming apparatus includes a first image bearing member on which a toner image can be formed; an intermediate transfer member onto which the toner image is transferable from the first image bearing member; wherein the toner image is further transferred onto a second image bearing member therefrom; wherein the intermediate transfer member comprises a conductive layer to which a voltage is applied, a surface layer on the conductive layer, and a volume resistivity of the surface layer is 10.sup.5 -10.sup.11 ohm.cm.

Abstract: The present invention relates to a fixing apparatus having a pair of rotary members for pinching and conveying a supporting material bearing a non-fixed toner image thereon, thereby fixing the non-fixed toner image on the supporting material and wherein a rectifier element is connected to at least one of the rotary members in a predetermined orientation, whereby the present invention prevent a toner offset that the toner on the supporting material is adhered to the rotary members.

Abstract: An image processing apparatus includes a read unit for reading image information from an original text, a detection unit for detecting position information of the image information, and a conversion unit for converting the position information in accordance with the output of the detection unit.

Abstract: An image forming apparatus includes a movable image bearing member; an image forming device for forming a toner image on the image bearing member; image transfer device for transferring the toner image from the image bearing member to a transfer material at an image transfer station, wherein the transfer device includes a charging member press-contacted or faced to the image bearing member and a device for applying a voltage to the charging member, wherein the voltage applying device applies a voltage to the charging member so that the charging member is constant-voltage-controlled when an image region of the image bearing member is in the transfer station, and the charging member is constant-current-controlled during at least a part of a period when it is not in the transfer station, wherein a voltage V2 applied during the constant voltage control is a voltage V1 appearing in the transfer device during the constant current control multiplied by a coefficient R, in which R is larger than 1.

Abstract: An image forming apparatus includes a movable image bearing member, an image forming device for forming the image bearing member, and an image transfer device contactable to the image bearing member at an image transfer position. The transfer device transfers the image formed by the image forming device onto a transfer material while the transfer material is conveyed through the transfer position together with the image bearing member, wherein the transfer device has a hardness of 20-40 degrees (Asker-C), and it is pressed to the image bearing member at a pressure of 50-200 g/cm.sup.2, and wherein a peripheral speed of the transfer device at the transfer position during a transfer operation is higher than a peripheral speed of the image bearing member at the transfer position.

Abstract: An image forming apparatus includes an image bearing member carrying an image corresponding to image information; an image transfer device for transferring the image on the image bearing member onto a transfer material at a transfer position, wherein the transfer device includes a charging member contactable to a back side of the transfer material and voltage application means for applying a voltage to the charging member, wherein the voltage applying device effects a constant voltage control to the charging member when an image region of the image bearing member is at the transfer position, and effects a constant current control to the charging member at least a part of the other duration, and wherein a voltage level of the constant voltage control is determined on the basis of a voltage across the transfer device during the constant current control; wherein voltage applied to the charging member by the voltage applying device or a current through the charging member by the voltage applying device is limited

Abstract: A developing apparatus including a developer carrying member for carrying a developer, a magnet disposed in the developer carrying member, and an elastic regulating member contacting the developer carrying member to regulate a thickness of a layer of the developer formed on the developer carrying member. The developer carrying member has a roughened surface over a width thereof larger than a width of the portion of the elastic regulating member contacting the developer carrying member while the magnet forms a magnetic field in a marginal region of the roughened surface of the developer carrying member not contacting the elastic regulating member to remove magnetic developer.

Abstract: An image forming apparatus includes a movable image bearing member; an image forming device for forming an image on the image bearing member; a transfer device for transferring an image from the image bearing member to a transfer material at a transfer position, wherein the transfer device is contactable to a backside of the transfer material at the transfer position and includes a charging member including a double oxide and a voltage source for applying a voltage to the charging member, and wherein the voltage source constant-voltage-controls the charging member when an image region of the image bearing member is at the transfer position, and constant-current-controls the charging member in at least a part of a period when the image region of the image bearing member is not at the transfer position, wherein a constant voltage for the constant voltage control is determined on the basis of the constant current control.

Abstract: A developing apparatus including a developing roller for carrying an one component developer to a developing zone for developing an electrostatic latent image. The developing roller is provided with a surface layer which contains long carbon fibers extending substantially parallel to the axis of the developing roller or extending in a direction inclined relative to the roller axis, and a binder for binding the carbon fibers.

Abstract: An image transfer apparatus for transferring a toner image onto a transfer material includes an image bearing member for carrying a developed toner image; image transfer bias applying roller for contacting to a backside of the transfer material, for urging it to the image bearing member having the toner image and for applying a transfer bias to transfer the toner image to the transfer material; wherein amounts of charge applied to the transfer material by the transfer bias applying roller during its transfer operation satisfyA.gtoreq.B/2where A (Coulomb/cm.sup.2) is an amount of the charge at a portion where a surface potential of the image bearing member is relatively low, and B (Coulomb/cm.sup.2) is an amount of the charge at a portion where the surface potential of the image bearing member is relatively high. Then, disturbance to the image by the image transfer operation can be avoided.

Abstract: A developing apparatus using one component developer includes a developing sleeve for carrying the developer to a developing zone. The developing sleeve has an outer coating layer made of resin material in which electrically conductive fine particles are dispersed.

Abstract: In a duplex image forming apparatus, first and second image forming devices are arranged respectively in upstream and downstream sides of a moving direction of a transfer member. Each image forming device includes an image bearing member, a developer for forming on the image bearing member a toner image corresponding to first and second information signals, respectively, and a transfer device for transferring the respective toner images to respective sides of the transfer member. A reader is provided for reading a first side of an original and, at a point of time after reading of the first side begins, a second side of the original. The length of time required to move the transfer member from the first transfer station to the second transfer station is equal to the length of time between beginning to read the first side of the original and beginning to read the second side of the original.

Abstract: An image forming apparatus employs a non-magnetic developing agent and a magnetic developing agent which have been charged to opposite polarities to develop at least first and second latent images formed on an image carrier in response to image information, thus forming first and second developed images. The first and second developed images are charged to the same polarity as that of the magetic developing agent, prior to the transfer onto a transfer medium so as to provide a vivid transferred image.

Abstract: A magnet roll, comprising a main body portion of a soft material and having a surface portion which is permanently magnetized, and a supporting portion integrally formed with the main body portion by the same soft material as of the main body portion for mounting the main body portion to a member to which the main body is to be mounted.

Abstract: An image forming apparatus includes movable image bearing member, a first charger means for charging the image bearing member, first electrostatic latent image forming device for forming a first electrostatic latent image in accordance with image information on the image bearing means charged by the first charger, first developing device for developing the first electrostatic latent image, a second charger for re-charging the image bearing member, second electrostatic latent image forming device for forming a second electrostatic latent image in accordance with image information on the image bearing member recharged by the second charger, second developing device for developing the second electrostatic latent image, a dector for detecting a surface potential of the image bearing member, the detector detecting at least the surface potential at that portion of the latent image formed on the image bearing member by the first latent image forming device which is developed, after the portion is charged by the seco