Abstract: An image forming apparatus including, a plurality of image bearing members, a plurality of developing units which includes toner storage containers and a belt transferring toner images onto a transfer material, the image forming apparatus being capable of executing a first cleaning mode and a second cleaning mode to move the toner adhering onto the belt onto the image bearing members and to collect the adhering toner into the toner storage containers, wherein, in the first cleaning mode, the adhering toner is collected into the toner storage container of the developing unit developing a black toner, and in the second cleaning mode, a portion of the adhering toner is collected into the toner storage container corresponding to the image bearing member located at a most upstream position and a rest of the adhering toner is collected into the toner storage container of the developing unit developing the black toner.

Abstract: An image forming apparatus which predicts VL fluctuations of a photosensitive drum in consideration of a double-sided print mode, and performs an image formation control based on the prediction, and thus always obtains a stable density image. The image forming apparatus performs an appropriate image formation control by controlling an image forming condition based on a photosensitive member rotation time, a photosensitive member stop time, a temperature of an atmospheric environment, an absolute humidity of the atmospheric environment, and whether an image formation that precedes a subsequent image formation is performed in single-sided printing or double-sided printing.

Abstract: A color image forming apparatus in which a positional displacement detection image and a light quantity adjustment image are formed within a one-rotation length of an image bearing member (intermediate transfer belt). A light-emission quantity when detecting density is determined on the basis of a detection result of a light quantity adjustment image formed within the one-rotation length using light-emission quantity that is provided when light is emitted to the positional displacement detection image. This allows, for example, image density control to be performed quickly while precision of the image density control is maintained.

Abstract: An image forming apparatus which predicts VL fluctuates of a photosensitive drum, taking a rotation speed of the photosensitive drum during image formation into consideration, and controls the image formation based on the prediction, for always obtaining an image of a stable density. The image forming apparatus performs appropriate image formation control by controlling image forming conditions based on a photosensitive member rotation time, a photosensitive member stop time, a temperature of the environment, an absolute humidity of the environment, and the rotation speed of the photosensitive member.

Abstract: There is provided an image forming apparatus that accurately obtains the dynamic characteristic of the apparatus when a foreign substance is adhered to a driving roller for driving an endless belt, such as a facing roller. To accomplish this, the image forming apparatus uses an optical sensor to detect information of a foreign substance on the facing roller. When it is determined that there is no foreign substance information, the image forming apparatus executes profile detection of an intermediate transfer belt using the nominal circumference of the facing roller. When the optical sensor detects foreign substance information, the image forming apparatus measures the circumference of the facing roller, and performs profile detection of the intermediate transfer belt using the measured circumference of the facing roller.

Abstract: An image forming apparatus which predicts VL fluctuations of a photosensitive drum in consideration of a double-sided print mode, and performs an image formation control based on the prediction, and thus always obtains a stable density image. The image forming apparatus performs an appropriate image formation control by controlling an image forming condition based on a photosensitive member rotation time, a photosensitive member stop time, a temperature of an atmospheric environment, an absolute humidity of the atmospheric environment, and whether an image formation that precedes a subsequent image formation is performed in single-sided printing or double-sided printing.

Abstract: A color image forming apparatus in which a positional displacement detection image and a light quantity adjustment image are formed within a one-rotation length of an image bearing member (intermediate transfer belt). A light-emission quantity when detecting density is determined on the basis of a detection result of a light quantity adjustment image formed within the one-rotation length using light-emission quantity that is provided when light is emitted to the positional displacement detection image. This allows, for example, image density control to be performed quickly while precision of the image density control is maintained.

Abstract: The image forming apparatus includes a conductive member provided in a conveying path of a recording material, a voltage applying device for applying a voltage to the conductive member, a current detecting device for detecting a current flowing in the conductive member when the recording material passes through the conductive member to which a voltage is applied by the voltage applying device, and a judgment device for judging, based on an output from the current detecting device, whether a conductive foreign object is present on the recording material. Thus there is provided an image forming apparatus capable of detecting a foreign object attached to a recording material by a simple method.

Abstract: A cleaning apparatus for use in an image forming apparatus removes toner, including spherical toner particles, from an image bearing member for bearing a toner image for use in an image forming apparatus. The toner to be removed is a one-component toner having a shape coefficient SF1 of 100 to 120. The apparatus has blade-shaped elastic member rubbing a surface of the image bearing member for removing the toner and is urged against a surface of the image bearing member with a line pressure of 55 to 95 g·f/cm. The elastic blade is formed so that a thickness of a portion, supported by a support member, of the elastic blade is larger than a thickness of a free end of the elastic blade.

Abstract: The present invention provides a cleaning apparatus for cleaning a toner including spherical toner particles from an image bearing member for bearing a toner image for cleaning it. The toner to be removed is one-component toner having shape coefficient SF1 of 100 to 120, and the apparatus has blade-shaped elastic member rubbing a surface of the image bearing member for removing the toner and is urged against a surface of the image bearing member with line pressure of 55 to 95 g/cm.

Abstract: An image forming apparatus has an image bearing member for bearing a different color toner image; a movable intermediate transfer member; voltage applicator for applying a voltage to the intermediary transfer member to effect electrostatic, sequential and superimposing transfer of the different color toner images from the image bearing member onto the intermediary transfer member at a transfer position A first toner image on the intermediary transfer member passes through the transfer position in the period which is after a first toner image is transferred from the image bearing member onto the intermediary transfer member by the voltage applicator and which is before a second toner image which is immediately subsequent to the first toner image is transferred from the image bearing member onto the intermediary transfer member; and a control for switching a voltage applied to the intermediary transfer member from a first voltage for transferring the first toner image from the image bearing member onto the inte

Abstract: An image forming apparatus includes a movable image bearing member for bearing different color toner images; a movable intermediary transfer member including an electroconductive layer and a surface layer; first transferring means for applying a voltage to the electroconductive layer to sequentially and superimposedly transfer the different color toner images from the image bearing member onto the intermediary transfer member at a first transfer position; second transferring means for electrostatically transferring the different color toner images from the intermediary transfer member on the transfer material at a second transfer position, wherein the second transferring means is disposed faced to such a side of the intermediary transfer member as receives the toner image; wherein the image forming apparatus is operable with the transfer material having a length measured in a direction of feeding of the transfer material, which is longer than a distance between the first transfer position to the second transf

Abstract: An image forming apparatus prevents the transfer, onto an intermediate transfer member, of the remaining toner after having passed under a cleaning blade by the small vibration phenomenon thereof induced by the shock resulting from the stopping or starting of the rotation of a photosensitive drum. At the start-up of the image forming apparatus or at the end of the printing operation, the intermediate transfer member is separated from the photosensitive drum. Then, after the start of the printing operation, the photosensitive drum is rotated while it is separated from the intermediate transfer member. Then the photosensitive drum is contacted with the intermediate transfer member after an abutting portion on the photosensitive drum, where the cleaning blade is in contact in the stopped state of the image forming apparatus, passes through a position opposed to the intermediate transfer member, and the image forming operation is then initiated.

Abstract: An image forming apparatus has an image bearing member, an image forming unit for forming a toner image on the image bearing member and having a first charge member for charging the image bearing member, a rotatable intermediate transfer member onto which the toner image on the image bearing member is transferred at a first transfer position, the toner image on the intermediate transfer member being transferred onto a transfer material at a second transfer position, and a second charge member for charging residual toner remaining on the intermediate transfer member, the second charge member charging the residual toner on the intermediate transfer member with polarity opposite to charging polarity of the first charge member for charging the image bearing member, after the toner image is transferred from the intermediate transfer member to the transfer material.