Abstract: In one example, method includes displaying an estimate of the number of pages that can be printed from a total amount of printing fluid including a printing fluid supply and a printing fluid reserve. The estimate is decremented in amounts of a first interval, in response to a first sensor signal indicating that the printing fluid supply is not empty. The estimate is decremented in amounts of a second interval that is smaller than the first interval, in response to a second sensor signal indicating that the printing fluid supply is empty.

Abstract: An image forming apparatus includes developer accommodating containers, mounting portions for the respective containers, a switching portion, and a manually operable cover. In a stand-by state after exchange of one of the developer accommodating containers is prompted, the switching portion switches a state of the container from a non-accessible state to an accessible state with opening of the cover. In a case that a jam occurrence signal is ON after the exchange of the developer accommodating container mounted in the mounting portion is prompted, the switching portion maintains the non-accessible state without switching from the non-accessible state to the accessible state at the time of the opening of the cover.

Abstract: An image forming apparatus includes a toner cartridge, a developer, and a processor. The toner cartridge includes an accommodation container accommodating toner and a memory storing a first toner residual amount display threshold value. The developer performs development by the toner supplied from the toner cartridge. The processor calculates a second toner residual amount display threshold value based on a toner supply index, indicating an amount of the toner supplied to the developer from at least one toner cartridge used before a toner cartridge mounted on the image forming apparatus, and the first toner residual amount display threshold value. The processor outputs notification relating to a toner residual amount when a toner supply index indicating an amount of toner supplied to the developer from the toner cartridge mounted on the image forming apparatus exceeds the second toner residual amount display threshold value.

Abstract: According to one embodiment, an image forming apparatus includes a printer unit and a control unit. The printer unit forms an image on a sheet using a developer, and includes a predetermined driving member related to supply of the developer. The control unit acquires driving information regarding continuous driving of the driving member, acquires correction information regarding on correction of an amount of the developer used in accordance with the driving information, and estimates a remaining amount of the developer on the basis of the driving information and the correction information.

Abstract: An image forming apparatus includes a developing device that forms a toner image on a sheet; a supply device provided with a cartridge for accommodating toner and supplying the toner in the cartridge to the developing device; a sensor that acquires a physical quantity relating to an amount of toner in the developing device; a timer that counts time; and a controller that drives the supply device until a condition that the acquired physical quantity indicates that the amount of toner is equal to or greater than a predetermined value is satisfied when a condition that the physical quantity indicates that the amount of toner becomes small is satisfied, counts time during which the supply device is being driven with the timer, and determines that the amount of toner in the cartridge becomes smaller than a predetermined amount if the counted time is longer than a predetermined threshold value.

Abstract: Provided is a locking mechanism in which when the urging force of an urging member is larger than the magnetic force of a magnet in the non-excited state, a plunger can be held at a first position, and when the urging force of the urging member is smaller than the magnetic force of the magnet in the non-excited state, the plunger can be held at a second position.

Abstract: A system is disclosed. The system at least one physical memory device to store ink estimation logic and one or more processors coupled with the at least one physical memory device, to execute the ink estimation logic to generate first estimated ink usage data for each of one or more color planes based one or more gray level histograms and one or more halftone designs, detect a change to a tone curve of one or more of the color planes, modify the gray level histograms and generate second estimated ink usage data for each of the color planes based on the modified gray level histograms, wherein each gray level histogram corresponds to one of the one or more color planes and each halftone design corresponds to one of the one or more color planes.

Abstract: A developer container according to an embodiment includes: a container having a space that contains a developer; an optical system includes a first optical member including first end face exposed to a containing space in the container and a second optical member including a second end face exposed to the containing space and being opposed to the first end face in a first direction, and on which the light is incident through the second end face; a shaft provided in the containing space to be rotatable about the first direction; a cleaning member provided to the shaft to be movable in the first direction to clean the first and second end faces by passing through a gap with a rotation of the shaft; and a guide member provided upstream of the optical system and that comes into contact with the cleaning member to guide the cleaning member to a gap.

Abstract: An image forming apparatus includes a controller to control a driving device such that a rotational speed of a supplying and feeding screw when it is rotated a predetermined number of times to supply developer to a developing device in a predetermined amount during execution of a continuous image forming job on a plurality of first recording materials is a first rotational speed, and a rotational speed of the supplying and feeding screw when it is rotated the predetermined number of times to supply the developer in the predetermined amount during execution of a continuous image forming job on a plurality of second recording materials is a second rotational speed slower than the first rotational speed. The second recording materials have a length longer than the first recording materials with respect to a sub-scan direction.

Abstract: A developing device includes a developer container, a developer carrier, first and second stirring/transporting members, a driving motor, first and second magnetic permeability sensors, and a control portion. The first magnetic permeability sensor is arranged in a first conveying chamber in the developer container, in a region other than a part facing a communication portion and senses the toner concentration in developer in the developer container. The second magnetic permeability sensor is arranged in a second conveying chamber in the developer container, in a region between a regulating portion and a downstream end of the developer carrier in the second direction. The control portion controls the supply amount of developer based on the output value of the first magnetic permeability sensor, and calculates the stable volume of developer in the developer container based on the difference between the output values of the first and second magnetic permeability sensors.

Abstract: An image forming apparatus includes an inner cover, an outer cover, a first pressing portion, and a restricting portion. The inner cover is opened and closed for a developer storage portion storing developer to be attached or detached. The outer cover is made of resin and provided on an outer side of the inner cover, and opened and closed in a same direction as the inner cover. The first pressing portion is provided on the outer cover and, when the outer cover is closed in a state where the inner cover is opened, comes into contact with and presses the inner cover in a closing direction. When the inner cover is closed, the restricting portion is engaged with the inner cover at a lock position located on an upstream side of a predetermined closing position of the inner cover in the closing direction, and restricts opening of the inner cover.

Abstract: An image forming apparatus includes lock mechanisms, a regulation processing portion, and a second release processing portion. The lock mechanisms correspond to attachment portions to each of which a developer storage portion is attached, and each regulate detachment of a developer storage portion attached to an attachment portion. When a first state where developer storage portions of a specific type are attached to all the attachment portions, has been detected, and there is a lock mechanism that is not regulating detachment, the regulation processing portion causes the lock mechanism to regulate detachment of the developer storage portion. When a second state where a developer storage portion of the specific type has not been attached to at least one attachment portion, has been detected, and all the lock mechanisms are regulating detachment, the second release processing portion causes all the lock mechanisms to release regulation of detachment.

Abstract: A base toner amount is determined without taking edge effect into account, and corresponds to a pixel value of image data for which gradation correction has not been performed. For the base toner amount, a first spatial filter process is performed corresponding to a laser profile of the exposure device. A second spatial filter process is performed for the base toner amount before or after the first spatial filter process and thereby an edge emphasis amount is determined corresponding to the edge effect. A limiter processing unit limits the edge emphasis amount to an uppermost value or less, and the uppermost value corresponds to the base toner amount after the first spatial filter process. A toner counter counts as a toner consumption amount a sum of the base toner amount after the first spatial filter process and the edge emphasis amount.

Abstract: A developer container is manufactured in which, in molding, a recess is disposed in an area in which a confluence in which first resin poured from a first inlet and second resin poured from a second inlet merge is formed.

Abstract: An image forming apparatus includes a first controller having an image processor that performs image processing on image data, the first controller configured to determine a first statistic value based on the image data, and output the first statistic value; an obtaining unit configured to obtain the image data; an image forming unit configured to form, based on the image data, an image by using toner; a supply unit configured to supply toner to the image forming unit; and a second controller configured to control the supply unit based on the first statistic value. In a case where the first statistic value is not outputted by the first controller in a predetermined period, the second controller controls the supply unit based on a second statistic value, the second statistic value being determined based on the image data.

Abstract: Provided is a consumables discharge device that discharges toner via an image carrier and an intermediate transfer body including a patch forming unit that forms a patch in a patch printing region to be formed on the intermediate transfer body via the image carrier by using the toner discharged from a developer tank after adjusting a range of the patch printing region in one or both of a gap region existing between image forming regions adjacent to each other of the intermediate transfer body and both end regions adjacent to both ends of an image forming region in a width direction of the intermediate transfer body, based on one or both of a size and a direction of a recording medium to be printed as input information.

Abstract: A power supply apparatus according to the present disclosure includes a first circuit, a second circuit isolated from the first circuit, an adjustment unit configured to adjust power supplied to a load, a first controller, a detection unit configured to detect a parameter related to the power supplied to the load, a first communication unit, a second communication unit configured to perform wireless communication with the first communication unit, and a second controller. The first communication unit is operated by power supplied by a signal generated in the first communication unit due to a signal output from the second controller. The first communication unit transmits, to the second communication unit, information about a result of detection by the detection unit. The second controller supplies the first controller with a signal for controlling the adjustment unit. The first controller controls the adjustment unit based on the signal.

Abstract: An image forming device includes: a developing device; a first toner container; a second toner container; a first vertical transport part; a second vertical transport part; a first horizontal transport part; a second horizontal transport part; a third horizontal transport part; a third vertical transport part, a counting unit; and a consumption amount calculation unit. The consumption amount calculation unit, in accordance with a rotation time accumulated by the counting unit, calculates a flow rate of toner flowing in the third horizontal transport part in each of the first supply state and the second supply state, and thereby calculates a toner consumption amount of each of the first toner container and the second toner container.

Abstract: An image forming apparatus of an exemplary embodiment includes a temperature sensor, a developing unit, a supply unit, and a control unit. The temperature sensor detects a temperature. The developing unit supplies developer to an image carrier and performs development. The supply unit contains developer and supplies the contained developer to the developing unit. The control unit executes developer replacement processing including discharging the developer from the developing unit and supplying the developer contained in the supply unit to the developing unit based on a first ratio which a ratio of a developer supply time during which the supply unit performs supply of the developer for the developing unit and a drive time during which the developing unit is driven and a threshold value obtained based on a detected temperature of a temperature sensor.

Abstract: An image forming apparatus includes a developing device, an image bearing member, an image density detecting portion, a toner content detecting portion, a humidity sensor, a supplying portion, and a controller configured to control the supplying portion so that a toner content is between an upper limit and a lower limit thereof. The controller can execute setting control in which the target value of the toner content is set on the basis of an image density of a reference toner image. The controller sets the lower limit until execution of subsequent setting control, wherein the lower limit is higher when a humidity is a first humidity and an average image ratio is a first ratio than when the humidity is a second humidity higher than the first humidity and the average image ratio is a second ratio larger than the first ratio.

Abstract: An image forming apparatus includes a first determination section, a calculation section, a second determination section, and a billing section. The first determination section determines whether a toner container attached to a toner supply section is a first container or a second container. The calculation section calculates a consumption amount of a toner in the toner container determined as the second container. The second determination section determines whether the consumption amount is a threshold value or larger. When the consumption amount is less than the threshold value, the billing section changes a billing price from a first price to a second price. When the toner container is determined to be the first container, the billing section changes the billing price from the first price to a third price. The second price is lower than the first price. The third price is equal to or lower than the second price.

Abstract: A developer supplying device has a storage container, a detection sensor, and a cleaning member. The storage container stores developer. The detection sensor has a detection face making contact with the developer in the storage container and detects the amount of developer in the storage container. The cleaning member cleans the detection face by making contact with the detection face. The storage container has a sensor movement face formed arc-shaped about a predetermined center as seen in a sectional view. The detection sensor is configured to be movable in the up/down direction along the sensor movement face. The cleaning member rotates about the predetermined center as a rotation axis.

Abstract: An image forming apparatus to which a cartridge including an electronic storage device can detachably be attached, comprises: an obtaining unit that obtains control information used for image formation from a first area of the electronic storage device and obtain determination information used to determine correctness of the control information stored in the first area from a second area configured to store the determination information; a determination unit that determines the correctness of the control information based on the control information and the determination information; and a control unit that, if the determination unit determines that the control information is correct, controls image formation using the control information obtained by the obtaining unit.

Abstract: A system and method for reducing toner waste during startup of a print operation for electrostatic printers includes a controller that is configured to delay the biasing and rotation of a developer roller until initially uncharged portions of a photoconductive drum have rotated past the developer roller. At the start of a print operation the controller rotates a photoconductive drum and activates a charge corona to put an initial charge on the photoconductive drum, which is thereafter selectively removed in accordance with the image to be printed. The charge corona and developer roller are angularly displaced from one another such that at the start of a print job uncharged portions of the photoconductive drum are initially rotated past the developer roller. Delaying the biasing and rotation of the developer roller prevents toner from being transferred from the developer roller to the initially uncharged portions of the photoconductive drum.

Abstract: An image forming apparatus according to an embodiment may include a control section that controls operation of the image forming unit; a driving source that drives the image forming unit and drives, based on an instruction of the control section, rotation of a cleaning member whose sliding member passes a gap between a first light transmission window of a first optical path and a second light transmission window of a second optical path in a developer storing section while sliding on the first light transmission window and the second light transmission window. The control section detects, based on a light reception information detected by a light receiving element, a passage timing at which the sliding member passes through the gap, and stops the driving by the driving source based on the passage timing.

Abstract: One or more toner bottles are provided for supplying toners to development apparatuses. The toner bottles each include bottle portions and displacement sensors. The bottle portions accommodate the toners and are rotated by a drive force of a drive source. The displacement sensors are positioned on sides of the bottle portions and detect deflection amounts of the sides of the bottle portions to determine how much toner is remaining in each toner bottle.

Abstract: A powder detector includes a driver to drive a motor, a stirrer to stir powder in a vessel, a vibration plate disposed in the vessel and vibrated by a flip of the stirrer rotated by the motor, and circuitry. The circuitry detects a vibration of the vibration plate, estimates an amount of powder based on a detection result of the vibration, and causes the driver to drive the motor from a starting point, so as to move the stirrer to a preset halt position. The starting point is a rotation angle of the motor on detection of the vibration.

Abstract: An image forming apparatus, including: a photoconductor; a developing device; a developer storage; a supplier configured to supply developer to the developing device; and a controller configured to, when performing a printing operation, execute a developing process, a usage-amount obtaining process of obtaining a developer usage amount used in the developing process, a first supplying process of supplying the developer by operating the supplier by a first driving amount every time the usage amount becomes greater than or equal to a first threshold, and a second supplying process of supplying the developer by operating the supplier by a driving amount greater than the first driving amount when the usage amount from a time point of beginning of use of the developer storage becomes greater than or equal to a second threshold that is greater than the first threshold.

Abstract: A process cartridge includes a first cartridge and a second cartridge. The first cartridge includes a first wall having a first opening, a first shutter configured to open and close the first opening, and a first operating portion configured to operate together with the first shutter. The second cartridge is mountable onto and demountable from the first cartridge and contains a developer. The second cartridge includes a second wall facing the first wall and having a second opening corresponding to the first opening, a second shutter configured to open and close the second opening, and a second operating portion configured to operate together with the second shutter. The first cartridge further includes a third operating portion. When the second cartridge is mounted onto the first cartridge, the first operating portion and the third operating portion operate together through the second operating portion.

Abstract: A toner case includes a case main body, a rotator, a transmitter, a moving mechanism and a manipulation member. The rotator rotates around a rotation axis. At least a part of the rotator is stored in the case main body. The transmitter is arranged outside the case main body and transmits rotation to the rotator. The manipulation member is arranged outside the case main body. As the manipulation member moves from a first manipulating position to a second manipulating position, the moving mechanism moves the transmitter from a first position to a second position which is arranged at an outside of the first position in a rotation axis direction of the rotator. As the manipulation member moves from the second manipulating position to the first manipulating position, the moving mechanism moves the transmitter from the second position to the first position.

Abstract: A network system including a customer replaceable unit (CRU) having an excellent security function for operation information which system can realize improvement of the use efficiency of operation information for making the CRU operate, and reduction in costs, is provided. An apparatus main body of a multifunction printer, a server, a personal computer, etc. are connected to a network of a network system, and a CRU is attached to the apparatus main body so as to be detachable. Operation information necessary for making the CRU operate is stored in the server. The apparatus main body obtains operation information of the CRU from the server via the network and stores the obtained operation information into a buffer memory, and causes the CRU to operate based on the operation information. The operation information stored in the buffer memory is erased when communication between the apparatus main body and the CRU ends.

Abstract: A powder-amount detection device includes an outer electrode, an inner electrode, and a detector. The outer electrode is disposed outside a powder container to be replaceably installed to an image forming apparatus. The inner electrode is disposed inside a powder supply port of the powder container. The detector is configured to apply an electric field between the outer electrode and the inner electrode to detect a capacitance between the outer electrode and the inner electrode.

Abstract: An edge emphasis amount determining unit performs a spatial filter process and thereby determines an edge emphasis amount corresponding to edge effect. A first toner counter (a) counts a toner consumption amount including the edge emphasis amount for a non-block-edge pixel in a block as a unit of image processing, and (b) counts a toner consumption amount not including the edge emphasis amount for a block edge pixel in the block. A second toner counter counts a toner consumption amount not including the edge emphasis amount for the non-block-edge pixel and the block edge pixel. A toner consumption amount calculating unit calculates a toner consumption amount of the block on the basis of a difference between a toner counting value of the first toner counter and a toner counting value of the second toner counter.

Abstract: An image processing apparatus that is capable of calculating an appropriate replacement guide value of a part even in a case where the image processing apparatus operates under different operating modes. The image processing apparatus is capable of operating in a plurality of operating modes of different image forming speeds and has a replacement guide default value showing a guide for replacement of a part for each of the operating modes. A degree of wear of the part for each of the operating modes is calculated based on the replacement guide default value. The calculated degree of wear is, in a case where the operating mode is changed, converted to a degree of wear for the operating mode after the change, and a replacement guide value of the part in the operating mode is calculated after the change based on the converted degree of wear.

Abstract: A printer controller determines whether a cartridge refilled with a recording material is mounted on an image forming apparatus. If it is determined that the cartridge refilled with the recording material is mounted on the image forming apparatus, control for shifting a printer engine to a predetermined state is performed, raw data is acquired from the printer engine that has been shifted to the predetermined state, and a user is notified of the degree of wear of the cartridge based on the acquired raw data. On the other hand, if the printer controller determines that the cartridge refilled with the recording material is not mounted on the image forming apparatus, the printer controller acquires a predicted value from the printer engine, and notifies the user of the degree of wear of the cartridge based on the predicted value.

Abstract: An image forming device includes a developing device; a first toner container; a second toner container; a drive controller; and a consumption amount calculation portion. The drive controller switches a first replenishment state of replenishing a toner from the first toner container to the developing device and a second replenishment state of replenishing a toner from the second toner container to the developing device in response to a toner replenishment request from the developing device. The consumption amount calculation portion calculates a consumption amount of a toner in each of the first toner container and the second toner container by calculating a flow rate of each toner flowing through the first horizontal transport portion and the second horizontal transport portion.

Abstract: An image forming apparatus, including: a photoconductor; a developing device; a developer storage; a supplier configured to supply developer; an optical sensor; and a controller configured to execute: a developing process of developing an electrostatic latent image on the photoconductor; a usage-amount obtaining process of obtaining a usage amount of the developer; a supplying process of supplying the developer to the developing device every time when the obtained usage amount becomes equal to or greater than a first threshold; and a detecting process of detecting, by the optical sensor, an amount of the developer in the developing device every time when the obtained usage amount becomes equal to or greater than a second threshold larger than the first threshold, and wherein the controller is configured to execute the detecting process in a period different from a period in which the developing process is being executed.

Abstract: A base toner amount is determined without taking edge effect into account. The base toner amount corresponds to a pixel value of image data for which gradation correction has not been performed. For the base toner amount, a first spatial filter process is performed corresponding to a laser profile of the exposure device. A second spatial filter process is performed for the base toner amount before or after the first spatial filter process and thereby an edge emphasis amount is determined corresponding to the edge effect. A toner counter counts as a toner consumption amount a sum of the base toner amount after the first spatial filter process and the edge emphasis amount. Further, a gain control unit multiplies the edge emphasis amount by a coefficient corresponding to the base toner amount after the first spatial filter process and thereby controls a gain of the edge emphasis amount.

Abstract: A toner level detection assembly for an electrophotographic image forming device according to one example embodiment includes a rotatable shaft is positioned within a toner reservoir. A magnet is connected to the shaft and is rotatable with the shaft around an axis of rotation of the shaft. The magnet is pivotable independent of the shaft about a pivot axis that is spaced radially from the axis of rotation such that a radial distance of the magnet from the axis of rotation varies as the magnet pivots about the pivot axis. A first magnetic sensor is positioned to sense the magnet within a first range of radial distances from the axis of rotation. A second magnetic sensor is positioned to sense the magnet within a second range of radial distances from the axis of rotation.

Abstract: An image forming apparatus includes: an image bearing member, a developing device, and a controller configured to execute an operation in a forced consumption mode. The controller includes a difference calculating portion, an integrating portion, and a flag. In a case where the flag is set when a predetermined time is elapsed after the integrated value exceeds the predetermined threshold, the image formation on the predetermined number of the recording materials is effected and then the controller executes the operation in the forced consumption mode, and in a case where the flag is reset when the predetermined time is elapsed after the integrated value exceeds the predetermined threshold, the image formation on the predetermined number of the recording materials is effected and then the controller continues an image forming operation without executing the operation in the forced consumption mode.

Abstract: A toner supply device includes a toner container, a detector, and a determiner. The toner container is configured to contain toner to be supplied to a developing device. The toner container is capable of discharging a prescribed amount of toner contained therein. The detector is configured to detect an amount of toner to be supplied to the developing device. The determiner is configured to estimate a timing at which toner remaining in the toner container is completely consumed, based on a driving amount applied for discharging toner from the toner container during a time period from when the prescribed amount of toner is discharged from the toner container until when the detector detects an amount of toner equal to the prescribed amount of toner.

Abstract: An image forming apparatus is provided which can properly manage individual information after replacement and history of replacement on the apparatus side. If individual information is successfully read from a toner cartridge storing the individual information, the image forming apparatus records the individual information in an apparatus-side memory. At a predetermined timing of when there is a possibility that the toner cartridge is replaced, the image forming apparatus attempts to read information from the toner cartridge. If the reading fails and the individual information recorded in the apparatus-side storage is not information read from the toner cartridge, the image forming apparatus writes new individual information about the toner cartridge to the apparatus-side storage, and records information generated on the apparatus side in the written individual information.

Abstract: The voltage detection apparatus includes a transformer, in which a primary side and a secondary side are insulated from each other and the primary side connected in parallel with a first line and a second line, configured to output from the secondary side a voltage supplied to the primary side according to an alternating voltage; a detection circuit configured to detect a frequency of an alternating voltage; and a correction unit configured to acquire information corresponding to a voltage output from the transformer and information corresponding to a frequency detected by the detection circuit, and that corrects the information corresponding to the voltage according to the information corresponding to the frequency.

Abstract: An image forming apparatus includes an image bearing member, a developing device, and a controller capable of executing an operation in a forced consumption mode in which toner is consumed without being transferred onto a recording material. The controller includes a difference calculating portion configured to calculate a difference between an image amount of a predetermined image forming number and a reference value. The reference value is set i) at a first reference value when information on an average image amount per predetermined image forming number or per predetermined driving time of the developing device is less than a value corresponding to a predetermined reference image amount, and is set ii) at a second reference value lower than the first reference value when the information on the average image amount is not less than a predetermined reference image amount.

Abstract: A developing apparatus includes a partition member disposed in a first chamber above a discharge space communicated to the discharge port positioned downstream of a return conveyance portion in the first direction, and configured to divide a space within a first chamber in a gravity direction. The partition member is configured to extend from a wall portion on a downstream side of a developer container to a position corresponding to a downstream end of a return conveyance portion or to a position further upstream beyond the position corresponding to the downstream end of the return conveyance portion in the first direction. A surface, opposed to a first conveyance screw, of the partition member is positioned downward in the gravity direction than an upper end of a first communication port and upward in the gravity direction than the first conveyance screw.

Abstract: An image forming apparatus includes a correction amount calculator, a fluidity measuring unit, and an external additive amount calculator. The correction amount calculator calculates a correction amount of fluidity to correct the fluidity of a two-component developer. The fluidity measuring unit measures the fluidity of the two-component developer. The external additive amount calculator corrects the measured fluidity on the basis of the correction amount of fluidity, calculates the amount of an external additive of a toner from the corrected fluidity of the two-component developer, and determines the state of the external additive.

Abstract: An image forming apparatus comprises an expendable item having a specific function, installed replaceably with respect to a main body of the image forming apparatus, wherein there are several types of expendable items, and an engine control unit. The engine control unit judges end of lifetime of the expendable item by using one of a plurality of lifetime judgment methods. The engine control unit selects a lifetime judgment method used in the judgment, according to a type of the expendable item. It makes possible to provide an image forming apparatus capable of appropriately determining the reaching of the lifetime end of expendable items.

Abstract: An image forming apparatus includes a developing unit attachment part to which developing units are to be attached, each of the developing units being associated with a first criteria for performing developer refreshing and a second criteria for performing developer refreshing, wherein the second criteria is defined so as to be met prior to the first criteria, and a controller configured to control a timing of developer refreshing executed for each of the developing units according to the first and second criteria values thereof, and a first developer tank that is located at a position higher than the developing unit and configured to contain the developer. When the first criteria for performing developer refreshing is met for at least one of the developing units, the controller causes developer refreshing to be performed for all developing units whose first or second criteria is met.

Abstract: An image forming apparatus includes a controller configured to, each time a development roller of a developing device rotates by a particular rotational amount, increment a counter value stored in a storage, calculate a remaining amount of developer in the developing device, when the counter value is less than a first value, setting a remaining amount threshold to a first threshold, whereas, when the counter value is equal to or more than a second value, setting the remaining amount threshold to a second threshold, the second value being equal to or more than the first value, the second threshold being less than the first threshold, and when the calculated remaining amount is less than the set remaining amount threshold, control a transporter to transport developer stored in a developer box to the developing device.

Abstract: An image forming apparatus comprises a controller, an adjustment unit configured to adjust an image forming condition based on an adjustment condition corresponding to a profile of a toner adhesion amount in a sheet conveying direction, and an image forming unit configured to form an image on a sheet with the adjusted image forming condition while conveying the sheet.