Abstract: An image forming apparatus including an exposure device, a development device, an image density detection device, a supply device for supplying a toner to the development device, a cleaning device for cleaning the surface of an image bearing member, a driving torque detection device for detecting a driving torque of the image bearing member, and a controller which drives the image bearing member while providing a predetermined electric potential difference between a region charged in the image bearing member and a developer support in case of non-image formation conducts a driving torque detecting operation with respect to the image bearing member by means of the driving torque detection device, and changes a reference value in response to the value of the driving torque detected.

Abstract: In the case where image formation is performed by using a part of a plurality of image forming units, an associated image bearing member of a remaining part of the plurality of image forming units is rotated together with an intermediary transfer member or a recording material carrying member while a voltage of a polarity opposite to that of polishing particles is applied to an electric charge imparting member.

Abstract: An image forming apparatus includes first and second image forming units each including a charging device and a development device using a developer including a mixture of toner and carrier, a transfer device for serially transferring toner images onto a transfer medium, a replenishment device for replenishing a replenishing developer including a mixture of toner and carrier to each development device, and a discharge device for discharging the developer. The second image forming unit is disposed on a downstream side of the first image forming unit in a transfer medium travel direction. Each development device of the first and second image forming units is configured to recover a residual transfer toner remaining on each image bearing member. A weight percent of carrier in the replenishing developer to be replenished to the development device of the second image forming unit is larger than that of the first image forming unit.

Abstract: An image forming apparatus is constituted by a rotatable image bearing member; a charging member for electrically charging the image bearing member in contact with the image bearing member; developing member, containing polishing particles, for collecting toner from the image bearing member and effecting development on the basis of an electrostatic latent image formed on the image bearing member; a transfer member for transferring a toner image formed on the image bearing member onto a transfer material; an auxiliary charging member, located downstream from a transfer portion and upstream from the charging member with respect to a movement direction of the image bearing member, for electrically charging toner remaining on the image bearing member after the transfer by contact with the image bearing member; and control means for performing a discharging mode, for discharging polishing particles from the auxiliary charging member onto the image bearing member on the basis of an image ratio of an image to be for

Abstract: An image forming apparatus includes an image bearing member on which an electrostatic image is formed; a developing device for developing the electrostatic image formed on the image bearing member with a developer including toner and a carrier; a supplying apparatus for supplying into the developing device a supply developer including toner by rotating a feeding screw; inclination detecting means for detecting an inclination of the feeding screw; and control means for controlling rotation of the feeding screw on the basis of a result of detection of the inclination detecting means.

Abstract: An image forming apparatus includes a first developing device for developing an electrostatic image with a developer including toner and carrier; a second developing device for developing an electrostatic image with a developer including toner which is different from the toner and carrier; first supplying means for supplying the toner into the first developing device; second supplying means for supplying the toner into the second developing device; toner content detecting means for detecting a toner content in the developer in the first developing device; image density detecting means for detecting an image density of a reference toner image formed using the first developing device and the second developing device; and control means for operating the apparatus selectively in a first mode in which an image forming operation is carried out using only the first developing device out of the first developing device and the second developing device, and the first supplying means supplies the toner using at least a

Abstract: An image forming apparatus includes an image bearing member having a surface layer; an electrostatic image forming device for forming an electrostatic image on the surface layer; a developing device, containing at least toner and a carrier, for developing the electrostatic image; a density measuring device for measuring a density of the developed electrostatic image; a layer thickness measuring device for measuring a thickness of the surface layer; and an adjusting device for adjusting toner content in the developing device. The adjusting device adjusts the toner content on the basis of an output of the layer thickness measuring device.

Abstract: An image forming apparatus includes: a developing unit for developing a latent image on an image bearing member by using a developer containing toner and a carrier; and a detecting unit for detecting a density of a detection reference toner image, wherein detection results obtained by the detecting unit are employed to control a toner replenishment operation for the developing unit, and wherein, when the detection results obtained by the detecting unit is equal to or smaller than a predetermined value, a residual toner amount determination mode is performed.

Abstract: An image forming apparatus includes an image bearing member having a surface layer; electrostatic image forming means for forming an electrostatic image on the surface layer; developing means, containing at least toner and a carrier, for developing the electrostatic image; density measuring means for measuring a density of the developed electrostatic image; layer thickness measuring means for measuring a thickness of the surface layer; adjusting means for adjusting toner content in said developing means. The adjusting means adjusts the toner content on the basis of an output of the layer thickness measuring means.

Abstract: An image forming apparatus includes an image bearing member for bearing an electrostatic latent image; a developing device for developing the latent image on the image bearing member with a developer including toner and carrier particles at a developing position, the developing device including a developer carrying member for carrying the developer, a plurality of developing devices containing toner particles which have colors different from each other, and a moving mechanism for carrying the developing devices to move a selected one of the developing devices to the developing position. The apparatus further includes a density detector for detecting a toner density on the developer carrying member the devices located at a position different from the developing position; a controller, responsive to an output of the density detector, for controlling toner contents in the developing devices.

Abstract: An image forming apparatus includes an image bearing member having a surface layer; an electrostatic image forming device for forming an electrostatic image on the surface layer; a developing device, containing at least toner and a carrier, for developing the electrostatic image; a density measuring device for measuring a density of the developed electrostatic image; a layer thickness measuring device for measuring a thickness of the surface layer; and an adjusting device for adjusting toner content in the developing device. The adjusting device adjusts the toner content on the basis of an output of the layer thickness measuring device.

Abstract: An image forming apparatus includes: a developing unit for developing a latent image on an image bearing member by using a developer containing toner and a carrier; and a detecting unit for detecting a density of a detection reference toner image, wherein detection results obtained by the detecting unit are employed to control a toner replenishment operation for the developing unit, and wherein, when the detection results obtained by the detecting unit is equal to or smaller than a predetermined value, a residual toner amount determination mode is performed.

Abstract: An image forming apparatus capable of preventing the increase of the size thereof by having a lengthened developer bearing member is provided with regard to an image forming apparatus capable of printing a registration mark (dragonfly) on a large sheet of recording paper for producing an art work in case of the use of a formed image as a printing manuscript. The length of the lengthwise direction of a developer bearing member provided in at least one developing device among the developing devices provided in the image forming apparatus is longer than those of the developer bearing members of the other developing devices.

Abstract: An image forming apparatus includes an image bearing member for bearing an electrostatic latent image; developing means for developing the latent image on the image bearing member with a developer including toner and carrier particles at a developing position, the developing means including a developer carrying member for carrying the developer, a plurality of developing devices containing toner particles which have colors different from each other, and moving means for carrying the developing devices to move a slected one of the developing devices to the developing position, the apparatus further including density detecting means for detecting a toner density on the developer carrying member of a the devices located at a positioin different from the developing position; control means, responsive to an output of the density detecting means, for controlling toner contents in the devices, wherein when the density detecting means effects its density detecting operaration in an operation mode, in which only one o

Abstract: An image forming apparatus includes: a developing unit for developing a latent image on an image bearing member by using a developer containing toner and a carrier; and a detecting unit for detecting a density of a detection reference toner image, wherein detection results obtained by the detecting unit are employed to control a toner replenishment operation for the developing unit, and wherein, when the detection results obtained by the detecting unit is equal to or smaller than a predetermined value, a residual toner amount determination mode is performed.

Abstract: An image forming apparatus capable of preventing the increase of the size thereof by having a lengthened developer bearing member is provided with regard to an image forming apparatus capable of printing a registration mark (dragonfly) on a large sheet of recording paper for producing an art work in case of the use of a formed image as a printing manuscript. The length of the lengthwise direction of a developer bearing member provided in at least one developing device among the developing devices provided in the image forming apparatus is longer than those of the developer bearing members of the other developing devices.

Abstract: An image forming apparatus includes an image bearing member having a surface layer; electrostatic image forming means for forming an electrostatic image on the surface layer; developing means, containing at least toner and a carrier, for developing the electrostatic image; density measuring means for measuring a density of the developed electrostatic image; layer thickness measuring means for measuring a thickness of the surface layer; adjusting means for adjusting toner content in said developing means. The adjusting means adjusts the toner content on the basis of an output of the layer thickness measuring means.