Abstract: An image-forming apparatus includes a photosensitive drum, a developing roller, a cam, a switching mechanism, a sheet tray, a sheet feed mechanism, a sheet sensor, and a controller. The switching mechanism rotates the cam to move the developing roller from a contact position in contact with the photosensitive drum to a separated position away from the photosensitive drum after development for the first sheet, if feeding of a second sheet is not started after elapse of a prescribed time period since detection of a first sheet. If image data for the second sheet is ready and upon elapse of a predetermined standby time period from elapse of the prescribed time period, the sheet feed mechanism starts feeding the second sheet toward the photosensitive drum and the switching mechanism rotates the cam to move the developing roller to the separated position in accordance with conveyance of the second sheet.
Abstract: An image forming apparatus includes: an image bearing member; a developer carrying member to correspond to the image bearing member; drive portion to rotationally drive the developer carrying member; control unit to control the rotational drive by the drive portion, and detection portion to detect information from the toner patch. Modes for controlling, by control unit, the rotational drive of the drive portion include (i) a first mode which uses a first driving condition including a first peripheral speed ratio between the developer carrying member and the image bearing member and (ii) a second mode which uses a second driving condition including a second peripheral speed ratio which is higher than the first peripheral speed ratio. The control unit controls the image bearing member to form the toner patch for each of peripheral speed ratios and sets the second driving condition on the basis of the detected information.
Abstract: In one example, a development cycle of a binary ink developer, BID, is timed. Timing may be based on the length of a substrate in which the image is to be printed or the size of the image or the area to be printed with the ink associated to the BID.
January 30, 2020
Date of Patent:
October 13, 2020
HP Indigo B.V.
Asaf Shoshani, Lavi Cohen, Ido Finkelman, Meir Grinstein
Abstract: An image forming apparatus includes: a casing; a toner cartridge; a drum cartridge; a main electrode; a first reading portion; and a controller. The toner cartridge is attachable to the drum cartridge and includes: a developing roller; and a developing electrode electrically connected to the developing roller. The drum cartridge is attachable to the casing and includes: a photosensitive drum; a pressing member; and a drum memory. The pressing member presses the toner cartridge toward the photosensitive drum so that an outer circumferential surface of the developing roller contacts an outer circumferential surface of the photosensitive drum. The drum memory stores a pressing force value indicating a pressing force to be applied by the pressing member. The controller is configured to perform: reading, through the first reading portion, the pressing force value from the drum memory; and applying a voltage to the main electrode based on the pressing force value.
Abstract: An image forming apparatus includes a developing unit, a transferring unit, and a fixing unit. The developing unit performs an attachment process in which the developing unit attaches a luminescent toner to a latent image that is formed on a basis of image data. The transferring unit performs a transfer process in which the transferring unit transfers, onto a medium, the luminescent toner attached to the latent image. The fixing unit performs a fixing process in which the fixing unit fixes, to the medium, the luminescent toner transferred onto the medium. The attachment process performed by the developing unit and the transfer process performed by the transferring unit are each performed plural times for the medium, on the basis of the image data.
Abstract: A developer supplying device includes a supply driving portion supplying a developer from a developer supplying container to a developer accommodating portion, where it is agitated by an agitating conveyance portion. An agitating driving portion drives the agitating conveyance portion, and a control portion controls the supply driving portion and the agitating driving portion such that, each time the agitating conveyance portion is driven by a first driving amount, the supply driving portion is driven by a second driving amount. The control portion sets a different value of the first driving amount in accordance with a supplying property in a case where the developer is supplied from the developer supplying container to the developer accommodating portion.
Abstract: An image forming apparatus includes a controller to control a driving unit that rotates a developing rotary member. Rotation speed of the developing rotary member is controlled to become a first rotation speed in an image forming period. Rotation speed of the developing rotary member is decelerated from the first rotation speed in a first period of a non-image forming period so that the rotation speed becomes a second rotation speed lower than the first rotation speed, and rotation speed is decelerated from the second rotation speed in a second period subsequent to the first period of the non-image forming period so that the rotation of the developing rotary member is stopped. A deceleration amount per unit time of the developing rotary member in the first period is smaller than a deceleration amount per unit time of the developing rotary member in the second period.
Abstract: In an image forming apparatus, the image bearing member has a surface and configured to rotate about an axis. The collection device is in contact with the surface, and configured to collect materials adhered to the surface. The developing roller is configured to provide a charged toner having a first polarity. The processor is configured to perform: executing a print job in a printing period; executing, in a non-printing period, a first process in which the image bearing member is rotated at least one rotation while a holding bias is applied to the collection device, the holding bias having a second polarity opposite to the first polarity; and executing, in a non-printing period after the first process, a second process in which the image bearing member is rotated while an ejection bias is applied to the collection device, the ejection bias having the first polarity.
Abstract: A developing device includes upper and lower developer containing portions to contain developer, arranged in a vertical direction, a first developer conveyor to convey developer in the upper developer containing portion to a first side in an axial direction of the first developer conveyor, a second developer conveyor to convey developer in the lower developer containing portion to a second side opposite the first side, a developer-lifting area in which the developer is lifted from the lower developer containing portion to the upper developer containing portion, a first lifting area gear to rotate the first developer conveyor, a second lifting area gear to rotate the second developer conveyor, and a lifting area input gear to input a driving force to the developing device. The lifting area input gear is coupled to the first lifting area gear and coupled via the first lifting area gear via to the second lifting area gear.
Abstract: An image forming apparatus includes an image carrying member, a developing device, a cleaning unit and a processor. The developing device performs development with a developer containing a toner and a lubricant. The processor obtains information on a lubricant amount in the developing device; obtains, with respect to each section formed by dividing a surface of the image carrying member in a rotating shaft direction of the image carrying member, a partial coverage from electrostatic latent image writing information for a predetermined period about the section; sets, for the section having the partial coverage of a predetermined value or less, a developer supply amount for a patch to be formed outside an image forming region on the image carrying member, based on the above information; and causes the developing device to supply the set developer supply amount so that the patch is formed.
Abstract: A Toner Saver Feature (TSF) that enables adjustments in toner throughputs thus enhancing a user's control on toner consumption and thereby increasing life of cartridges in printing devices is disclosed. The disclosed TSF is configured to change throughput for each of the plurality of colorants based on at least one Preset Colorant Saver Configuration (Preset) that contains a set of Throughput Rate Reduction (TRR) values for each colorant, and wherein the at least one preset colorant saver configuration is user configurable. TSF enables a user to change the set of TRR values for each of the plurality of colorants individually through a user interface, and save the changed values as one of the Presets. The reduction values get implemented in all modes of printing wherein factory set throughput rates for the current mode get further reduced based on the selected Preset.
June 27, 2017
Date of Patent:
November 13, 2018
KYOCERA DOCUMENT SOLUTIONS INC.
Philip Ver Paloma Dabon, Neil-Paul Payoyo Bermundo, Kendrick Esperanza Wong, Jesus Reyes Beltran
Abstract: An image forming apparatus includes an image forming portion having a first feeding member to feed developer in a first chamber, a second feeding member to feed the developer in a second chamber; and a control portion to execute a plurality of modes by suspending image forming. A first mode circulates the developer in a condition in which a ratio of a rotational speed of the developer bearing member to a rotational speed of the first and second feeding members is decreased as compared to that in forming the images; and a second mode increases the ratio of the rotational speed of the developer bearing member to the rotational speed of the first feeding member as compared to that in forming the images. The second mode is executed after the first mode and before resuming the image forming operation.
Abstract: An image forming apparatus that continuously carries out image formation on a plurality of recording materials includes an image bearing member and a developing device configured to develop an electrostatic latent image on the image bearing member. A first feeding screw is provided in a developing chamber and includes a first screw portion, a second screw portion and a third screw portion. Each of the second and third screw portions are provided with a blade portion formed helically on an outer peripheral surface of a rotation shaft of the first feeding screw, and the first screw portion is not provided with the blade portion. Based on information on the relative humidity in the developing container and on the amount of toner consumed with the image formation on a plurality of recording materials, a controller controls a driving speed for rotationally driving the first feeding screw by a driving device.
Abstract: An image forming apparatus is operable in a mode of forming an image using only a part of image forming stations. In the mode, a developing device contacts an image bearing member in the part of the image forming stations, and the developing device is spaced from the image bearing member in the rest of the image forming stations. The contact pressure between the image bearing member and a transferring device is made smaller in the rest than in the part. The image forming operation in the mode is executed while the image bearing members of the part and the rest are rotated. A controller is configured such that when the operation in the mode is continuously executed for a time period longer than a predetermined period, the contact pressure in the rest is made larger than the above-mentioned smaller contact pressure.
Abstract: An image forming apparatus includes: an image bearing member to which lubricant is supplied; a developing section that forms a toner image by attaching toner to an electrostatic latent image formed on the image bearing member; and a control section that controls an amount of the lubricant in the developing section based on an area ratio of the toner image formed on the image bearing member and a development condition when the toner image is formed by the developing section.
Abstract: A recording apparatus includes a controller configured to: decrease the number of recording pages which is stored in a storage in response to completion of recording on a recording medium on a page-by-page basis; increase the number of recording pages in response to an increase in an amount of image data in the storage; determine whether the number of recording pages is greater than or equal to a first number; control a drive source and a recording device to convey the recording medium at a first speed and perform recording when the number of recording pages is less than the first number; and control the drive source and the recording device to convey the recording medium at a second speed greater than the first speed and perform the recording when the number of recording pages is greater than or equal to the first number.
March 30, 2016
Date of Patent:
January 2, 2018
Brother Kogyo Kabushiki Kaisha
Tomoyasu Yabuki, Motohiro Tsuboi, Yuji Mori
Abstract: A developing device includes a casing containing a two-component developer including toner and carrier, a developer bearer to transfer the developer on the developer bearer to a developing area, a toner density sensor to output an output value based on toner density of the developer, a toner density detection module to detect the toner density based on the output value of the toner density sensor and output characteristics relating the toner density and the output value, an acquisition module to acquire the output characteristics based on the output value of the toner density sensor relating a new developer and a predetermined toner density of the new developer, a bulk density fluctuation estimating module to estimate bulk density fluctuation for bulk density of the new developer, and a correction module to correct the output value based on the estimated bulk density fluctuation.
Abstract: An image forming apparatus that forms an image on a printing medium by an electrophotographic system in accordance with input image data, the apparatus including: a plurality of image forming units configured to form images in colors different from one another; a first determination unit configured to determine whether or not toner amount adjustment is necessary based on a possibility of the occurrence of a ghost for image data that is used for image formation in a second image forming unit located on the upstream side of a first image forming unit that is located on the downstream side in a conveyance direction of the printing medium of the plurality of image forming units; and a toner amount adjustment unit configured to make toner amount adjustment for the image data that is used for image formation in the second image forming unit in accordance with the determination results by the first determination unit.
Abstract: An image forming apparatus includes image bearing members, a latent image forming portion, developing units each including a developing member, a movable member, a common driving source, a contact-and-separation unit, and a control unit. The image forming apparatus is capable of forming the images in an operation in an image forming mode. After end of the latent image formation on one of the image bearing members on which latent image formation is finally started and before end of transfer of an associated image from the one image bearing member, the control unit outputs a spacing signal for spacing associated developing members from the other image bearing members, during the image formation in the operation in the mode.
Abstract: An image forming apparatus includes a developing unit and a supply amount increasing unit. The developing unit supplies oil-impregnated particles to an image carrier and develops an electrostatic latent image by a developer on the image carrier which is electrically charged to a polarity that is opposite a polarity of the developer which is electrically charged to a positive polarity or a negative polarity, based on a potential difference between a developing part and the image carrier. The supply amount increasing unit increases an amount of supply of the oil-impregnated particles to the image carrier by adjusting the potential of the image carrier, while a developing operation is not being performed by the developing unit.
Abstract: An image forming apparatus including a control device configured to predict, before printing a print job, whether or not a temperature of developer carried on a developing roller during the printing of the print job, in which the developing roller is rotated at a predetermined rotational speed, becomes equal to or higher than a first predetermined value by using a temperature detected by a temperature detector, rotate the developing roller at the predetermined rotational speed in a case where the predicted temperature does not become equal to or higher than the first predetermined value, and rotate the developing roller at a low speed lower than the predetermined rotational speed from a start to an end of the printing of the print job in a case where the predicted temperature becomes equal to or higher than the first predetermined value.
Abstract: An image forming apparatus includes: an image bearing member on which a toner image is formed; an image forming section configured to form the toner image by attaching toner mixed with lubricant to the image bearing member, and transfer the toner image formed on the image bearing member to a sheet; a computing section configured to compute a time average value of a coverage of the toner image transferred to the sheet by the image forming section for each of a plurality of different time periods; and a control section configured to control the image forming section to form a toner image of a pattern for forcible toner ejection on the image bearing member in accordance with a result of computing of the computing section.
Abstract: A developing unit includes a casing, a developer carrier, a developer conveying path, a developer conveying member, and a layer thickness regulator. The developer carrier is driven to rotate in the casing and carries a toner on the circumferential surface. The developer conveying member is located in the developer conveying path and driven to rotate so as to convey the developer in a second direction and to supply the toner to the developer carrier. The layer thickness regulator is spaced from the developer carrier, and regulates a layer thickness of the developer supplied to the developer carrier. The developing unit is configured to satisfy a condition of 2.0<Vd/Vs<7.0, where Vd denotes a circumferential velocity of the developer carrier and Vs denotes a circumferential velocity of the developer conveying member.
Abstract: An image forming apparatus includes an image forming device to form a toner image on a sheet; a fixing device to fix the toner image on the sheet; a toner container to house the toner to be supplied to the image forming device, the toner container arranged above the fixing device; a cooling fan; a guide to guide an airflow coming from the cooling fan to an outer circumferential surface of the toner container; an outer-circumferential flow path to serve as an airflow path between the outer circumferential surface of the toner container and a wall facing the outer circumferential surface, the outer-circumferential flow path guiding the airflow coming from the guide along the outer circumferential surface; a suction fan to suck the airflow having passed through the outer-circumferential flow path; and an exhaust guide to discharge the sucked airflow.
Abstract: In a development device, a developer carrier arranged in a housing containing a one-component developer has a circumferential surface carrying the developer. A developer conveying path includes one conveying path along the developer carrier in a first direction and another conveying path in a second direction opposite to the first direction. The developer is circulated and conveyed between the conveying paths. A developer conveying member is arranged in the one conveying path and rotationally driven to convey the developer along the first direction and to supply the developer to the developer carrier. A layer thickness adjusting member is arranged at a distance from the circumferential surface to adjust a layer thickness of the developer supplied to the developer carrier. The developer carrier has a circumferential speed Vd and the developer conveying member has a circumferential speed Vs so that a circumferential speed ratio Vd/Vs satisfies a relationship represented by 1.3?Vd/Vs?5.0.
Abstract: When a toner charging amount for toner in a liquid developer conveyed to a development portion is set, a wet-type image formation apparatus performs a sensing operation in which a sensing unit senses image densities of a plurality of patch images formed at different development biases with the toner charging amount being set to a constant value, and a setting operation in which, in a case where a control unit calculates current development characteristics based on the image densities of the plurality of patch images sensed by the sensing unit, and determines that the current development characteristics are not included within a set target range, the control unit controls a charging unit to set the toner charging amount such that the development characteristics are included within the set target range.
Abstract: An image forming apparatus is capable of executing, in non-image formation, for example, in a sheet-to-sheet interval, a developer bearing member stop mode in which the developer conveyance by a development sleeve is stopped. For example, the apparatus turns off primary transfer bias in the sheet-to-sheet interval. Even if fogging toner is no longer supplied after the development sleeve drive is stopped, the apparatus can reduce frictional force variation between the photosensitive drum and the intermediate transfer belt to prevent speed variation of the photosensitive drum or the intermediate transfer belt, thus reducing the possibility of image unevenness and out of color registration.
Abstract: Provided is an image forming apparatus, including a first image portion that uses a first toner, and a second image portion that uses a second toner having a particle diameter greater than a particle diameter of the first toner, wherein, in a case where a first image of the first image portion is formed on a recording medium and a second image of the second image portion is formed on the first image, as compared to a case where only the first image is formed on the recording medium, an amount of the first toner per unit area of the first image increases.
Abstract: To provide an image forming apparatus that includes a plurality of image forming units and executes a mode for image formation by using a selected image forming unit, the image forming apparatus being able to restrict a decrease in productivity and restrict an image defect such as a lack of part of an image output during the execution of the mode. In a monochrome mode for forming an image only with a black toner, in the first image forming unit, a toner is caused to adhere to a region on a photosensitive body corresponding to a sheet interval and hence the toner is supplied to a cleaning blade by applying a development bias to a developing unit without applying a direct-current voltage to a charger of a color image forming unit not used for the image formation. Also, an alternating-current voltage is applied to the charger when the region on the photosensitive body from which the toner is removed by the cleaning blade passes through the charger.
Abstract: An image forming apparatus has an image carrier, a developing unit, a toner container, a pixel counter, and a used toner amount estimator. An electrostatic latent image is formed on the image carrier's surface. The developing unit feeds toner on the image carrier's surface. The toner container with a transport screw supplies toner to the developing unit. The pixel counter counts the number of pixels in toner images formed on the image carrier's surface since the toner container started being used. The used toner amount estimator estimates the amount of toner used, until the cumulative value of the number of revolutions of the transport screw reaches a predetermined number, based on the cumulative value and, thereafter, by multiplying the pixel count of the pixel counter by a coefficient. The estimator corrects the coefficient based on the pixel count as observed when the cumulative value reaches the predetermined number.
Abstract: An image forming apparatus includes an image bearing member for bearing a image; a developing container for accommodating a developer comprising toner and carrier; a rotatable developer carrying member, provided in an opening of the developing container, for developing an electrostatic latent image formed on the image bearing member; a feeding device for feeding the developer in the developing container toward the developer carrying member; detecting device for detecting information relating to a consumption amount of the developer; and a controller for executing, when a image formation is continuously effected for a plurality of recording materials, a operation in a mode in which on the basis of a result of detection of the detecting device, the image forming operation is interrupted, and a operating condition of at least one of the feeding device and the developer carrying member is changed.
Abstract: The developing device includes a developing container that stores a developer including a non-magnetic toner and a magnetic carrier, a toner bearing member that bears the toner and conveys the toner to a developing portion and a separating portion wherein a surface of the toner bearing member includes a plurality of recess structures. A percentage of the recess structures per unit area in a toner bearing region of the toner bearing member is equal to or larger than 55%.
December 5, 2013
Date of Patent:
August 11, 2015
CANON KABUSHIKI KAISHA
Kenta Kubo, Tatsuya Tada, Satoru Yamanaka, Hideaki Okamoto
Abstract: An image forming apparatus has a developing device and a controller. The developing device includes a stirring member, rotatable at a first speed or at a second speed lower than the first speed, which varies, according to its speed, the amount of developer discharged out of the developing device. The controller drives the stirring member to rotate at the second speed, then switches the rotation speed of the stirring member to a third speed higher than the second speed but lower than the first speed, and then drives the stirring member to rotate at the third speed for a first period. The third speed is set higher the lower the fluidity of the developer.
Abstract: Provided is an image forming device including an image holding member that is rotatable at a first speed and a second speed, a developing unit that includes a developing part that is rotatable at a third speed and a fourth speed, and a carrying part that is rotatable at a fifth speed and a sixth speed, and a control unit that executes a change of a high speed mode in which the image holding member is operated at the first speed, the developing part is operated at the third speed and the carrying part is operated at the fifth speed to perform development and a low speed mode in which the image holding member is operated at the second speed, the developing part is operated at the fourth speed and the carrying part is operated at the sixth speed to perform development.
Abstract: In an image forming apparatus that is provided with a developing unit to develop an electrostatic latent image formed on an image carrier as a toner image, the developing unit is provided with a developer reservoir that is disposed between a supplying roller to feed developer agitated by an agitating member into the developer reservoir and a developing roller to cause the developer in the developer reservoir to adhere onto the latent image on the image carrier so as to be developed as the toner image. A control section controls driving of the supplying roller, independently from driving of the agitating member.
Abstract: An image forming apparatus includes an image forming portion; a supplying device for supplying a toner; a transfer device capable of transferring the toner image from the image forming portion onto a toner image receiving member; a first detecting portion for detecting a transfer current of the transfer device; a second detecting portion for detecting information on a toner amount of the transferred toner image; and a controller for controlling, during non-image formation, a supplying operation of the supplying device on the basis of a detection result of the first detecting portion when a toner image for measurement formed at the image forming portion is transferred by the transfer device at a transfer voltage lower than a discharge start voltage and on the basis of a detection result when the toner image for measurement transferred on the toner image receiving member is detected by the second detection portion.
Abstract: An image forming apparatus includes: a cartridge installing section in which a first cartridge and a second cartridge are selectively installable; and a controller. The first cartridge includes: a first case configured to contain a first developer; a first developing roller; and a first transport member configured to transport the first developer toward the first developing roller. The second cartridge includes: a second case configured to contain a second developer, an amount of the second developer being greater than an amount of the first developer; a second developing roller; and a second transport member configured to transport the second developer toward the second developing roller. The controller is configured to control a drive source to drive one of the first transport member and the second transport member.
Abstract: A method of controlling toner concentration in an image forming device by determining a charge per unit mass of toner in a mixture of toner and carrier and adding toner to the mixture if the charge per unit mass of the toner is higher than a predetermined threshold. Other methods and devices are disclosed.
February 13, 2014
Date of Patent:
May 19, 2015
Lexmark International, Inc.
Marc Cousoulis, Courtney Harrison Soale
Abstract: An image forming apparatus includes an image bearing member, a developer carrying member, a first chamber for permitting feeding of the developer to the developer carrying member, and a second chamber for forming a circulation path of the developer at end portions thereof. The second chamber collects the developer from the developer carrying member at an opposing position, and a screw member feeds the developer contained in the first and second chambers. In addition, a supplying portion supplies a developer, a discharging portion, provided in the circulation path, causes an excessive developer to overflow, and a controller controls, on the basis of information on a first drive time from a start of rotation of the screw member to an end of a developing operation, a second drive time from the end of the developing operation to a stop of the rotation of the screw member.
Abstract: Image forming apparatus is disclosed. The developing portion is replenished with toner from a toner containing body by operating a toner feeding mechanism. The receiving portion receives a designation of switching to a low speed i.e. switching the rotation speed of the motor from the first speed to the second speed lower than the first speed. The measuring portion measures a value of a counter electromotive voltage generated in the motor by causing the motor to operate the toner feeding mechanism. The motor control portion causes the motor to rotate at the first speed until an absolute value of the value measured by the measuring portion is not larger than a predetermined first value, and causes the motor to rotate at the second speed after an absolute value of the measured value is smaller than the first value, in the case where the switching to a low speed is designated.
Abstract: Patch background data at each position of a background where a toner patch is formed in the second rotation is estimated from background measurement data at a plurality of positions detected in the first rotation and patch neighborhood measurement data detected in the second rotation at a plurality of positions where no toner patch is formed. Since the apparatus can execute density measurement before the light emission amount of a density sensor stabilizes, the time required for density measurement can be shorter than before. Since the change ratio of the light emission amount and the variation of the reflected light amount from the background are reflected on the patch background data, the density measurement accuracy can be improved.
Abstract: A detection device configured to detect a charge amount of toner on a developer carrier, comprises: an assembly including a quartz oscillator and having a first surface and a second surface that are provided in the quartz oscillator, the first surface having a recess and a projection formed in a direction in which the quartz oscillator vibrates; a capacitor connected to the assembly; a first measurement unit configured to measure a potential difference between two ends of the capacitor; and a second measurement unit configured to measure a frequency of the quartz oscillator, wherein in a case where an alternating-current power is applied to the assembly, the direction in which the quartz oscillator vibrates is parallel to the first surface.
Abstract: An image forming apparatus capable of forming an image includes an image bearing member on which an electrostatic latent image is to be formed, a developer carrying member for carrying a developer to visualize the electrostatic latent image, and a developer feeding member, having a foam layer at its surface, for feeding the developer to the developer carrying member by being rotated in contact with the developer carrying member. In addition, a controller is capable of executing an operation in a first mode in which the developer feeding member is rotated for a first time and then the electrostatic latent image is visualized at a first speed by the developer carrying member and an operation in a second mode in which the developer feeding member is rotated for a second time longer than the first time and then the electrostatic latent image is visualized at a second speed slower than the first speed by the developer carrying member.
Abstract: An image forming apparatus includes an image carrier that carries an electrostatic latent image; a developer supplying unit that supplies developer by being driven at a predetermined speed; a developing unit that develops the electrostatic latent image, while a transporting member transports the developer, a transport speed of the transporting member being switched to a plurality of speeds; a determining unit that determines whether or not an operation where a supply capacity of the developer supplying unit is greater than a transport capacity of the developing unit exceeds a predetermined threshold value and is continued; and a controller that performs control so that, when the determining unit determines that the operation exceeds the predetermined threshold value and is continued, an operation that was being executed immediately prior to the determination is stopped to forcefully drive the transporting member of the developing unit for a predetermined driving time.
Abstract: An image forming apparatus includes a latent-image bearing body, a charging unit, a latent-image writing unit, a development unit, a development power, and a bias control unit. After a start of an image forming operation, the bias control unit performs a process of constantly maintaining an output of a development bias at an adjustment bias value. The adjustment bias value is a central value in a periodic fluctuation range of the output of the development bias. At a timing at which a difference of the development bias from the adjustment bias value in the periodic fluctuation range is less than or equal to a predetermined threshold value, the bias control unit performs switching from the process of constantly maintaining the output of the development bias at the adjustment bias value to a process of periodically changing the output of the development bias based on development bias control data.
Abstract: In the present wet-type image formation apparatus, when setting a standard image formation condition, a control unit adjusts both a conveyance amount of toner and a charge amount of the toner in order to obtain a predetermined developing characteristic. During normal image formation, the control unit obtains the image density of a patch image formed at a high contrast potential and the image density of a patch image formed at a low contrast potential, adjusts the conveyance amount of the toner when the image density of the patch image formed at the high contrast potential is varied from the developing characteristic for the standard image formation condition, and adjusts the charge amount of the toner when the image density of the patch image formed at the low contrast potential is varied from the developing characteristic for the standard image formation condition.
Abstract: An image forming apparatus includes a rotatable photoconductor, a charging unit, an exposure unit to expose the photoconductor to reduce an electrical potential at the photoconductor, a developing unit to charge the toner held on a toner bearing member with friction and attract the toner to the exposed portion on the photoconductor by supplying a development voltage from a first power source and using an electrical potential difference between the toner bearing member and the photoconductor in the development area, a reverse development voltage controller to supply a reverse development voltage while a non-charged portion on the photoconductor passes the development area, and a developer reducing potential applier to supply a development restraining potential and an absolute value smaller than a target charging potential to the photoconductor while the reverse development voltage is supplied.
Abstract: An image forming device includes each of developing devices including an image carrying part, a charging part that charges the image carrying part, a developing part on which a developing voltage is applied and which attaches developer to the image carrying part to develop the electrostatic latent image, and a control part that controls each of the developing devices. The developers are a white developer and other color developers, one of the developing devices using the white developer being defined the white developing device, the others using the other color developers being defined the non-white developing devices, and a developing potential difference of the white developing device is smaller than other developing potential differences of the non-white developing devices, the developing potential difference being defined between the developing voltage and potential of the image carrying part of the each developing device.
Abstract: An image forming apparatus includes a toner forced consumption control unit that performs toner forced consumption control in which toner in a developing unit is forcibly consumed when a certain condition to perform the toner forced consumption control is met. The certain condition to perform the toner forced consumption control includes a specific performance condition that a transfer bias switching condition to switch a transfer bias to a superimposed transfer bias in which an alternating current component is superimposed on a direct current component, from a direct current transfer bias is met. When the specific performance condition is met, the toner forced consumption control unit performs preliminary toner forced consumption control in which the toner forced consumption control is performed before an image forming operation using the superimposed transfer bias is started.
Abstract: The present application discloses a container including: a housing including a primary portion for storing developer, and a secondary portion, which projects from the primary portion and is connected to a developing device; a conveying mechanism which conveys the developer in the primary portion to the secondary portion; and a detector which detects a state of the developer. The primary portion includes a facing wall which is situated at a boundary between the primary and secondary portions so that the facing wall faces a flow of the developer moving toward the secondary portion. The developer includes a flowing portion under the conveyance to the secondary portion by the conveying mechanism, and an adhering portion defined by an adhering layer made of developer adhered to the facing wall. The detector detects a decrease of the flowing portion and a decrease of the adhering portion individually.