An image forming apparatus includes an image bearing member, a transfer member, a supplying member for supplying a protective agent applied onto a surface of the transfer member, and a controller capable of controlling the supplying member. In a state in which the transfer member contacts the image bearing member during non-image formation other than during image formation in which the toner image is transferred from the image bearing member onto the recording material, the controller carried out control so that an operation in an application mode in which the protective agent supplied from the supplying member is applied onto the surface of the transfer member is executed.

An image forming apparatus includes a density detector, a determination unit, and a change unit. The density detector detects a density of a patch image formed on an image carrier over plural places. The determination unit determines whether plural detection results of the density detector are within a threshold. When the number of determination results, by the determination unit, that the density of the patch image is not within the threshold exceeds a predetermined number, the change unit changes (i) a detection timing at which the patch image is detected by the density detector or (ii) a formation position of the patch image on the image carrier.

An image forming apparatus includes an image forming device forming an image, a transfer belt having an image bearing surface on which the image moves to first and second regions, a sensor installed at an installation angle to the image bearing surface and including a light emitting element emitting light, a first and second light receiving elements receiving light reflected from the first and second regions, respectively, circuitry to generate first and second information according to light entered the first and second light receiving elements, respectively, generate, when the image moves, time information according to a difference between first and second times at each of which the first and second information, respectively, reach a threshold, obtain a tilt table based on the time difference information, and determine, by the tilt table, tilt information corresponding to the time information and indicating a difference between the installation angle and a reference angle.

An image forming apparatus includes an image forming device, a first transfer device including a first mover, a second transfer device including a second mover, a transfer-pressure changer, a detector, and circuitry. The detector detects a toner image and outputs a detection value indicating an amount of toner of the toner image adhering to the second mover. The circuitry calculates a variable value for the amount of toner varying with a change in a transfer pressure, based on the detection value and a target value of the amount of toner of the toner image to be transferred and adhere to the second mover, reflects the calculated variable value in the detection value to correct the detection value, adjusts an image-forming condition based on the corrected detection value, and sets the image-forming condition of the toner image in the image forming device based on the corrected detection value.

An image forming apparatus includes an exposure device, a developing device, an intermediate transfer body, a sensor, and a controller. The exposure device may irradiate light corresponding to a test pattern onto a photoconductor, the developing device may supply a developing agent to the photoconductor to form, on the photoconductor, a toner image corresponding to the test pattern, the intermediate transfer body may receive the toner image corresponding to the test pattern formed on the photoconductor, and a sensor may sense the test pattern transferred onto the intermediate transfer body. The controller may control the exposure device to adjust the irradiated light so the test pattern becomes a contone pattern having a uniform tone, and may diagnose a condition of a component of the image forming apparatus based on the sensed test pattern.

An image forming unit forms an image on a sheet. A control unit controls the image forming unit. A reading unit reads the sheet. An analysis unit analyzes a reading result acquired by the image formed on the sheet being read by the reading unit, and outputs an analysis result. A storage unit stores a printing condition used when the image was formed and the analysis result in association with each other. A computation unit computes a control parameter to be used by the control unit in order to control the image forming unit, with reference to the analysis result and the printing condition stored in the storage unit.

An image forming apparatus includes: an image forming portion having an image carrying member, a charging device, an exposing device, and a developing device; a developing voltage power supply; a control portion; and an image density sensor. The developing device has a developer carrying member that carries two-component developer and a toner concentration sensor. The control portion senses toner concentration during calibration or during first image formation after calibration for correcting image density based on the sensing result from the image density sensor. If the difference VtargetV between the output value V of the toner concentration sensor actually sensed and a target value Vtarget of the toner concentration sensor to be observed when the toner concentration equals a reference concentration is equal to or larger than a predetermined value, the control portion performs calibration again when the amount of toner consumed after calibration reaches a predetermined threshold value.

According to one embodiment, there is provided a toner cartridge used in an image forming apparatus including a processor which forms a toner pattern image on a photoconductive member, transfers the toner pattern image on a medium, and changes an image forming condition based on a detection result obtained by optically detecting the toner pattern image transferred onto the medium, the toner cartridge including: a toner accommodating container accommodating a toner, and a memory. The memory stores reference data which is determined according to toner characteristics in the toner accommodating container, and is used for applying a reference value for an optical detection result of a toner pattern formed by the toner on the medium.

An image forming apparatus includes image forming units, secondary transfer units, and first and second detection devices. Each image forming unit includes image forming devices, and a primary intermediate transfer body. Toner images formed by the image forming devices are primarily transferred to the primary intermediate transfer body. The secondary transfer units are provided for the image forming units, respectively. Each secondary transfer unit is configured to secondarily transfer the toner images on a corresponding one of the primary intermediate transfer bodies to a transfer body. The first detection device is configured to detect the toner images downstream of the most downstream secondary transfer position. The second detection device is provided in at least one of the image forming units. The second detection device is configured to detect the toner images between the most downstream primary transfer position in the primary intermediate transfer body and a secondary transfer position.

An image forming apparatus including: a movable intermediate transfer member onto which a toner image borne by an image bearing member is to be transferred; a detection unit configured to irradiate the toner image on the intermediate transfer member with light to detect reflected light; and a control unit configured to adjust a condition for forming the toner image based on a detection result of the detection unit, wherein a plurality of grooves extending along a movement direction of the intermediate transfer member are formed in a surface of the intermediate transfer member in a width direction intersecting the movement direction, and wherein grooves, formed within a range of the intermediate transfer member to which the light is irradiated by the detection unit, among the plurality of grooves are formed so that intervals each between adjacent grooves with respect to the width direction are regularly changed within a predetermined range.