Class / Patent application number | Description | Number of patent applications / Date published |
399030000 | By concentration detector | 63 |
20080219684 | IMAGE FORMING APPARATUS - An image forming apparatus is provided which is capable of forming higher-quality images by detecting a toner concentration with higher accuracy to attain appropriate toner supply and image density. A value obtained by adding a correction value based on a temperature, humidity, a print coverage, or the like to a developer concentration adjustment value is set as a control voltage value Vc which is to be inputted to a toner concentration sensor, and an output value of the toner concentration sensor is detected for each of process speeds. A difference between the output value detected and a value at reference process speed is calculated and based on the difference, a correction value is further calculated. Such another calculation of the correction value with use of the output value detected allows for highly accurate correction. | 09-11-2008 |
20080232830 | IMAGE FORMATION APPARATUS, AN IMAGE FORMATION PROCESS CONTROL METHOD, AND A RECORDING MEDIUM - An image formation apparatus including a toner cartridge for holding toner, an image supporting unit, on which an electrostatic latent image corresponding to a toner image is formed, a toner development unit for developing the latent image into the toner image with the toner, a detecting unit for detecting toner concentration of the toner image, and a control unit for controlling an amount of toner adhering to the latent image by adjusting a development bias voltage based on an output of the detecting unit. If control by the control unit based on the detection output of the detecting unit is insufficient, and consumption of the toner is out of a predetermined normal range, the control is carried out by estimating one of toner consumption amount and toner recovery amount in a direction that departs from the predetermined normal range. | 09-25-2008 |
20080273885 | IMAGE FORMING APPARATUS - An image forming apparatus includes a latent image carrier, a latent image forming unit, a developing unit, a toner supplier, a toner concentration detector, a prediction calculator, and a toner supply controller. The toner supplier includes a single driving source and supplies toner to a two-component developer at a predetermined supply position by driving a toner supply member with the driving source. The toner concentration detector detects a toner concentration in the developer at a predetermined detection position located upstream of the supply position. The prediction calculator predicts changes in the toner concentration in the developer over time at a prediction position located at the supply position or downstream of the supply position and upstream of a developer feed position to the developer carrier when toner is not supplied, based on a result of the toner concentration detection. The toner supply controller adjusts an amount of the toner supplied based on the prediction. | 11-06-2008 |
20080310865 | IMAGE FORMING APPARATUS - An image forming apparatus includes an image carrying member, a development unit, a first driving unit, a second driving unit, and a cleaning blade. The image carrying member forms a latent image thereon. The development unit develops the latent image formed on the image carrying member. The first driving unit drives the image carrying member. The second driving unit drives the development unit. The cleaning blade, contactable against the image carrying member, removes materials including toner remaining on the image carrying member. When an agent-empty development unit is filled with a developing agent, the second driving unit is activated to start a driving of the development unit, and the first driving unit is activated to start a driving of the image carrying member after starting a developing agent filling operation to the development unit. | 12-18-2008 |
20090003852 | Device for measuring concentration of toner in liquid developer, image forming apparatus provided therewith, and method for measuring toner concentration - Provided are a light-emitting portion | 01-01-2009 |
20090010660 | Developing Device of Electrographic Printing Apparatus, Non-Image-Region Toner Removing Device, Electrographic Printing Apparatus Using the Same, Electrographic Printing Method, and Method of Producing Glass Plate or Ceramic Plate - A developing device for an electrographic printing apparatus provided has stable performance and improved printing quality. The developing device ( | 01-08-2009 |
20090022507 | Liquid Toner Concentration Detecting Device, and Image Forming Apparatus and Method of Controlling Concentration of Liquid Toner - A first container is operable to accommodate a liquid toner, and provided with a window. A reflector is disposed in the first container. A light emitter is operable to emit light to the reflector through the window and the liquid toner. A light receiver is operable to receive the light reflected by the reflector through the liquid toner and the window. A detector is operable to detect a concentration of the liquid toner based on the light received by the light receiver. | 01-22-2009 |
20090060534 | DEVELOPING DEVICE AND IMAGE FORMING APPARATUS - A developing device has stirring members for conveying and stirring a developer-tank-contained developer and a developer holder, and has a developer replenishing tank for replenishing a replenishment developer to a developer tank; a toner concentration detecting sensor; a discharging mechanism for discharging an excessive amount of the developer-tank-contained developer outside the developer tank when the amount of the developer-tank-contained developer inside the developer tank exceeds a predetermined amount; and a control unit for replenishing the developer-tank-contained developer when it is detected that the toner concentration inside the developer tank is lower than a first reference value and for forcibly consuming the toner inside the developer tank and replenishing the replenishment developer when it is detected that the toner concentration inside the developer tank is higher than a second reference value that is higher than the first reference value. | 03-05-2009 |
20090074432 | IMAGE FORMING APPARATUS - An image forming apparatus including an image bearing member; a developing device forming a toner image; a toner supplying device including a toner container, a toner feeding passage, a pump, in which a first member is moved while rubbing a second member to feed a developer supplement including at least the toner, and a residual toner detector detecting the amount of the developer supplement remaining in the toner container. Even after the toner container achieves a near empty state, image forming operations are continued as long as a predetermined condition is satisfied while changing the pump's condition such that the pump is stopped, the ratio of the pump stopping period to the pump driving period is set to be greater than that before the near-empty detection, or the pump stopping period and the pump driving period are set to be longer than those before the near-empty detection. | 03-19-2009 |
20090080913 | DEVELOPING DEVICE, IMAGE FORMING APPARATUS, AND PROCESS UNIT - An information attaching unit attaches either one of carrier density information of initial developer and loose apparent density information of toner in the initial developer to a housing of a developing device. A density-information storage unit stores therein either one of the carrier density information and the loose apparent density information as electronic data. At least one of the information attaching unit and the density-information storage unit is provided before shipment of the developing device. | 03-26-2009 |
20090202261 | Image Forming Apparatus Having A Toner Concentration Sensor - An image forming apparatus includes an image carrier on which an electrostatic latent image is formed, a rotary developing device having N developer carriers, where N defines a total number of developer carriers, the N developer carriers carrying developers to develop the electrostatic latent image, and the rotary developing device moves the N developer carriers to a development position opposite to the image carrier, and a toner concentration sensor that measures toner concentrations of the developers carried in the developer carriers. A measurement position of the toner concentration sensor is set on a second virtual straight line with the second virtual straight line having a first angle or an angle that is double the first angle toward a first virtual straight line on a rotation orbit of the rotary device, and the first virtual straight line connects a rotation center of the rotary developing device and the development position. The N developer carriers are placed in turn in an order starting from a first developer carrier to an N-th developer carrier at the same angular interval as the first angle on the rotation orbit of the rotary developing device, and an angular interval between the N-th developer carrier and the first developer carrier is set to a second angle greater than the first angle. | 08-13-2009 |
20090214232 | DEVELOPING DEVICE AND IMAGE FORMING APPARATUS - The present invention provides a developing device and an image forming apparatus capable of carrying out excellent image formation for a long period by making the fluctuations in the toner concentration and the volume level of the developer inside a trickle developing device that uses a two-component developer as small as possible. The developing device having stirring members for conveying and stirring a developer-tank-contained developer and a developer holder, comprises a developer replenishing tank for replenishing a replenishment developer to a developer tank; a toner concentration detecting sensor; a discharging mechanism for discharging an excessive amount of the developer-tank-contained developer outside the developer tank when the amount of the developer-tank-contained developer inside the developer tank exceeds a predetermined amount; and control unit having memory means for storing the current toner concentration inside the developer tank, the reference toner concentration inside the developer tank, a corrected reference toner concentration calculated according to the formula of (the current toner concentration—a correction value), a predetermined replenishment amount to the developer tank and an allowable value for the current toner concentration with respect to the reference toner concentration, and computing means for calculating the corrected reference toner concentration and comparing the current toner concentration with the reference toner concentration and the corrected reference toner concentration. | 08-27-2009 |
20090214233 | DEVELOPING DEVICE AND IMAGE FORMING APPARATUS - The present invention provides a developing device and an image forming apparatus capable of carrying out excellent image formation for a long period by making the fluctuations in the toner concentration and the volume level of the developer inside a trickle developing device that uses a two-component developer as small as possible. The developing device having stirring members for conveying and stirring a developer-tank-contained developer and a developer holder, comprises a developer replenishing tank; a toner concentration detecting sensor; a trickle discharging mechanism; developer amount detecting means; and control unit for controlling the replenishment operation of replenishment toner and carrier at the time when the toner concentration is lower than a predetermined reference toner concentration, wherein the control unit carries out forced consumption operation for the toner inside the developer tank and replenishment operation for the replenishment toner and carrier in the case that the amount of the developer-tank-contained developer inside the developer tank is judged to be low using the developer amount detecting means. | 08-27-2009 |
20090220254 | IMAGE FORMING APPARATUS AND DENSITY CORRECTION METHOD - When a two-component developer stored in a developer tank has been replaced, an image forming apparatus performs (a) a first formation step of forming a reference toner image on a photoreceptor, (b) a detection step of detecting an amount of toner of the reference toner image, and (c) a supply step of supplying a predetermined amount of toner to the developer tank when the amount of toner detected in the detection step is less than a threshold. Moreover, the image forming apparatus repeats the first formation step, the detection step, and the supply step until the amount of toner detected in the detection step becomes not less than the threshold. This makes it possible to provide an image forming apparatus that is stable in image quality even immediately after replacement of developers. | 09-03-2009 |
20090232526 | Developer cartridge and image formation apparatus - A developer cartridge is provided, which contains developer made of toner and carrier and is detachably mounted in a body of an image formation apparatus. The developer cartridge is configured to include an ID chip in which a carrier content rate of the developer contained in an inner container of the developer cartridge is stored. | 09-17-2009 |
20090245821 | IMAGE FORMING APPARATUS AND IMAGE CONTROL METHOD - An image forming apparatus | 10-01-2009 |
20090257761 | DEVELOPER CONVEYING DEVICE, DEVELOPING DEVICE, PROCESS UNIT, AND IMAGE FORMING APPARATUS - A black developer is conveyed in a first conveyance chamber in a rotation axis direction while agitating with rotation of a first screw member. A black-toner-concentration detecting sensor detects a toner concentration of the black developer by having contact with the black developer conveyed inside the first conveyance chamber. An average of peak amounts of a pressing force on the black developer, which is conveyed inside the first conveyance chamber by the first screw member, with respect to the black toner-concentration detecting sensor is set within a range of 9.8 15 [N/m | 10-15-2009 |
20090257762 | IMAGE FORMING APPARATUS - In accordance with an embodiment of the embodiment of the invention, an image forming apparatus includes: an electrostatic image-bearing member; and a developing device. The developing device includes a developer-carrying member disposed to face the electrostatic image-bearing member, and a developer carried on the developer-carrying member. The developer includes a carrier having a volume-average particle size dc (μm) and a toner having a volume-average particle size dt (μm) of at most 5 μm and contained at a weight ratio C with respect to the carrier of from 5 to 10% and is controlled so as to provide a surface coverage F of the carrier with the toner of from 30 to 80% as calculated according to Formula (I): F=(¼)×(dc/dt)×(pc/pt)×C, wherein pc denotes a true specific gravity (−) of the carrier, pt denotes a toner absolute specific gravity (−), and C denotes a weight ratio (−) of the toner to the carrier. | 10-15-2009 |
20090269088 | REMAINING TONER QUANTITY DETECTOR, PROCESS CARTRIDGE AND IMAGE FORMING APPARATUS - A remaining toner quantity detector includes a detector to detect a projection formed on a toner bottle which is rotated, a counter configured to count the number of rotations of the toner bottle by the detector and integrate the count, and a discriminator configured to discriminate the toner quantity in the toner bottle on the basis of the integrated value by the counter. | 10-29-2009 |
20090297179 | TONER CONCENTRATION SYSTEM CONTROL WITH STATE ESTIMATORS AND STATE FEEDBACK METHODS - The present disclosure provides for an imaging machine having an imaging member including a method for maintaining a toner concentration. The method for maintaining the toner concentration comprises: determining a toner concentration (TC) measurement using a sensor; computing a state estimator output from the TC measurement and a pre-stored estimator gain matrix, K | 12-03-2009 |
20090310984 | DEVELOPING APPARATUS AND IMAGE FORMING MACHINE - The developing apparatus, having stirring members for conveying and stirring developer-tank-contained developer and a developer holder, comprises a developer replenishing tank; a toner concentration detecting sensor; a trickle-type discharging mechanism; a developer amount estimating sensor; and a controller for controlling replenishment operation for replenishing the toner and the carrier for replenishment to the developer tank when the toner concentration is lower than a predetermined reference toner concentration, wherein the controller determines the amounts of the toner and the carrier to be replenished on the basis of the calculated toner concentration and the estimated amount of the developer. | 12-17-2009 |
20090310985 | DEVELOPING APPARATUS AND IMAGE FORMING MACHINE - The developing apparatus, having stirring members for conveying and stirring developer-tank-contained developer and a developer holder, comprises a developer replenishing tank; a magnetic-type toner concentration detecting sensor; a trickle-type discharging mechanism; conveying state switching device for temporarily blocking the flow of the developer-tank-contained developer and for temporarily switching the circulating state of the developer-tank-contained developer to the staying state thereof; and a controller for controlling replenishment operation for replenishing the toner and the carrier for replenishment to the developer tank when the toner concentration is lower than a predetermined reference toner concentration, wherein the controller determines the amounts of the toner and the carrier to be replenished on the basis of the calculated toner concentration and the estimated amount of the developer. | 12-17-2009 |
20100080576 | IMAGE FORMING APPARATUS - An image forming apparatus includes a latent image carrier, a developing unit to develop a latent image on the image carrier with developer including toner and carrier, a developer bearing member, a first detector to detect a toner adhesion amount per unit area of a toner image developed by the developing unit, a second detector to detect humidity, and a controller to calculate an index indicating toner chargeability of the carrier based on detection results of the toner adhesion amount obtained by the first detector and perform a given control process based on calculation results thereof and including a data storage unit to store an algorithm to correct the index to a specific value according to a specific humidity, based on detection results of the humidity obtained by the second detector. The controller corrects the index obtained based on the amount of toner adhesion based on the algorithm. | 04-01-2010 |
20100086320 | IMAGE FORMING APPARATUS - A first developer container having a toner supplying opening is provided in a developing unit. A toner concentration sensor is arranged downstream of the toner supplying opening to detect toner concentration in developer. A supply controlling unit is provided to determine an excess or a shortage in the amount of supplied toner based on image information correspondingly to a detection result by the toner concentration sensor, and to correct the driving amount of a toner supplying unit that has been determined based on the image information correspondingly to the recognized excess or shortage in the amount of supplied toner. | 04-08-2010 |
20100111547 | IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD - An image-information acquiring unit acquires the image information divided at least in one of a main-scanning direction and a sub-scanning direction. A supply control unit calculates basic-supply patterns of a supply amount of toner and controls the supply amount at a supply point in a developing unit using a toner supply pattern combined with the basic-supply patterns that eliminate temporal variation in toner density of the developer, at the specific point, due to development of the latent image. | 05-06-2010 |
20100129092 | DEVELOPER DEVICE, IMAGE FORMING APPARATUS, AND TONER REPLENISHMENT METHOD - A differential sensitivity calculation portion calculates the differential sensitivity D of a toner concentration sensor, using an output voltage V | 05-27-2010 |
20100215386 | DEVICE AND METHOD FOR MEASURING CONCENTRATION OF LIQUID TONER - In a device and a method for measuring the concentration of liquid toner, for accurate detection of the concentration of liquid toner, provided are a rotary roller; a toner adhesion portion along the outer circumference of the roller, the toner adhesion portion being configured to hold liquid toner T; a sensor for detecting the concentration of the liquid toner based on the amount of light that is reflected from the liquid toner T adhering at a predetermined thickness to the toner adhesion portion; and a scraping blade for scraping off the liquid toner from the toner adhesion portion after the detection by the sensor, and apply voltage of the same polarity as that of the liquid toner to the toner adhesion portion when the liquid toner is scraped off by the scraping blade. | 08-26-2010 |
20100226664 | IMAGE FORMING APPARATUS AND METHOD FOR CONTROLLING IMAGE DENSITY THEREIN - An image forming apparatus includes a developer unit to store two-component developer which includes toner and carrier and develop an electrostatic latent image formed on the image carrier, a toner concentration detector to detect toner concentration in the developer unit, a toner supply unit to supply toner to the developer unit, and a controller to control toner supply amount by controlling the toner supply unit by comparing an output value of the toner concentration detector with a reference value stored in a memory and correcting difference between output values of the toner concentration detector at two or more process linear velocities in accordance with the toner concentration in the developer unit. A compensation amount for correcting difference between output values of the toner concentration detector that differ depending on the process linear velocity is adjustable in accordance with the toner concentration in the development unit. | 09-09-2010 |
20100260507 | DEVELOPING APPARATUS - In the present invention, for a developing apparatus provided with a sensor for detecting the toner density of a developer, retention of the developer near the sensor face can be suppressed by increasing the force with which the developer present near the sensor face is carried in a shaft direction of a stirring/carrying member. | 10-14-2010 |
20100266297 | IMAGE FORMING APPARATUS AND IMAGE CARRIER UNIT - Disclosed is an image forming apparatus including a toner reallocation electrode to carry out a reallocation of a toner of a toner image, a toner detection section to detect a toner amount of the toner image and a control section to calculate a toner amount adhered to the toner reallocation electrode or a density distribution of the toner image based on the detected toner amount and to control an AC component of an applied voltage based on the calculated toner amount or density distribution, and the control section decides a maximum value of the AC component of the applied voltage based on the toner amount or decides a minimum value of the AC component of the applied voltage based on the density distribution, and the control section controls the AC component within a control range of smaller than or equal to the decided maximum value or greater than or equal to the decided minimum value. | 10-21-2010 |
20100290794 | SCREEN CONFIGURATION FOR USE IN A TONER CONCENTRATION FIELD MEASUREMENT TOOL - A kit used in TC measurement in the field includes a sandwich of 3 screens used for filtration of carrier beads from toner particles within a container. An upper 400 mesh screen has die-cut holes around its edges to allow removal of any beads trapped between the upper screen and a middle 500 mesh screen. A bottom screen of coarse 20 mesh material is used for strength to support the other screens. When a vacuum source connected to a bottom portion of the container is turned ON, the carrier beads approach the screens in the center of the container. The recirculating airflow carries the carrier beads away from the upper screen at the edges. Thus, with the upper screen being die-cut with openings around its edges, these openings allow the trapped beads to return to the inner chamber of the container for removal during cleaning. | 11-18-2010 |
20100290795 | TONER CONCENTRATION SENSOR AND TONER CONCENTRATION CONTROL METHOD - In this toner concentration sensor, as the magnetic permeability of a two-component developer | 11-18-2010 |
20110020017 | DEVELOPER SUPPLYING DEVICE, DEVELOPING DEVICE, AND IMAGE FORMING APPARATUS - The developer supplying device supplies a supplementary developer including a toner and a carrier in a predetermined weight ratio. The developer supplying device includes a supplementary developer container containing the supplementary developer, and a supplementary developer feeding passage configured to feed the supplementary developer from the supplementary developer container to a developing device. The supplementary developer container is replaced when the supplementary developer is substantially exhausted. The developer supplying device further includes a carrier concentration determining device provided on the supplementary developer feeding passage to determine the concentration of the carrier in the supplementary developer fed through the supplementary developer feeding passage, and a residual supplementary developer amount estimating device configured to estimate the amount of the supplementary developer remaining in the supplementary developer container. | 01-27-2011 |
20110052223 | DEVELOPING DEVICE AND IMAGE-FORMING APPARATUS - A developing device comprises a developer unit that contains a developer including a color material and a magnetic powder, the color material being used to develop an electrostatic latent image held by an image holding member; a collecting unit that collects a part of the developer contained in the developer unit via a passage; and a measuring unit that measures a concentration of the color material included in the developer based on a magnetic property of the developer moving through the passage. | 03-03-2011 |
20110129240 | IMAGE FORMING APPARATUS, DEVELOPER DISCHARGE METHOD, AND COMPUTER PROGRAM PRODUCT THEREOF - An image forming apparatus includes a latent image carrier, a development device, a discharge port through which developer is discharged, a discharge port detector, and a controller that determines whether to permit driving of the development device in a direction reverse to a normal direction or to terminate discharge of developer based on detection results by the discharge port detector in discharge of developer. The development device includes a developer carrier, a developer supply member disposed in a supply compartment facing the developer carrier, a developer collection member disposed in a collection compartment lower than the supply compartment, a developer agitation member disposed in an agitation compartment disposed at a height similar to that of the collection compartment, to transport developer in a direction opposite conveyance direction by the developer supply member and the developer collection member. | 06-02-2011 |
20110243584 | DEVELOPING DEVICE - A developing device includes a developing container for containing a developer including toner and a carrier, a feeding member for feeding the developer in the developing container through a feeding path, and a detecting portion for detecting information on magnetic permeability of the developer in the developing container. A cross-section of said feeding path includes a first area and a second area which has a larger height than that of the first area, and said detection portion is provided vertically below the first area. | 10-06-2011 |
20110255887 | IMAGE FORMING APPARATUS - An image forming apparatus includes a latent image holder that holds a latent image; a developing unit that contains developer including toner particles and carrier particles, develops a latent image with the toner particles, and forms a toner image; a voltage applying unit that applies a voltage to the developing unit; a toner concentration detection unit that detects a toner concentration that is a proportion of the toner particles to the developer contained in the developing unit; and a setting unit that sets a setting value of the voltage on the basis of the toner concentration detected by the toner concentration detection unit, the voltage being applied by the voltage applying unit to the developing unit, wherein a difference between an upper limit and a lower limit of the set value increases as the toner concentration increases, the set value being set by the setting unit. | 10-20-2011 |
20110255888 | IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD - An image forming apparatus includes: a developing device having a developing vessel, a developing roller and a toner supply port; a toner supply device; a toner supply detecting sensor for detecting the toner concentration inside the developing vessel; a toner concentration controller for directing toner supply; a toner empty detector; and a sheet conveyance detecting sensor. The toner concentration controller has a toner supply device control function; and a toner supply stopping function of stopping toner supply when the last sheet of image printout being executed has passed by the predetermined position in the sheet conveyance path. | 10-20-2011 |
20110262155 | IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD USING THE SAME - An image forming apparatus can prevent printed images from being degraded in image quality due to failure of the toner concentration to fall within a proper range, by correcting the deviations of the amount of toner consumption and the amount of toner supply depending on the individuality of each image forming apparatus and that enables exact identification of the cause of a fault associated with toner concentration, as well as providing an image forming method using the apparatus. A toner supply device supplies toner to a developing vessel through an opening in accordance with an instruction from a controller. The presence or absence of toner falling is detected based on the variation of the output from a magnetic permeability sensor when toner is supplied. The controller monitors the output voltage level of the magnetic permeability sensor and adjusts the input gain in accordance with the output voltage level to thereby control toner concentration. | 10-27-2011 |
20110311244 | IMAGE FORMING APPARATUS AND METHOD - Certain embodiments provide an image forming apparatus including: a photoreceptor; a latent image forming unit; a developing device; a sensor that detects concentration of toner in the developing device; a storage unit that stores a prescribed time period for supplying replenishment toner and a first variation when the replenishment toner is supplied to the developing device for a prescribed time length; a toner cartridge that includes the replenishment toner and a toner discharge member; a driving unit that drives discharge of the toner discharging member; a calculating unit that calculates a second variation based on output of the sensor when the driving unit drives the toner cartridge for the prescribed time length; and a control unit that corrects the prescribed time length in the storage unit on a basis of the first and the second variations and controls the driving unit for driving for corrected time length. | 12-22-2011 |
20120020684 | IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD AND PROGRAM USING THE SAME - Provided are an image forming apparatus that, when a difference between a developing bias in correcting an image density and a reference developing bias has a value not less than a prescribed value that is set preliminarily, replenishes or consumes a toner forcibly, executes correction of the image density again, and controls the developing bias in such a manner that a toner density is controlled to fall within an appropriate range, and an image forming method using the same. When a difference between a developing bias value after correction of the image density and the reference developing bias becomes larger than the prescribed value to the plus side or the minus side, a toner density control portion performs control to consume or replenish a toner forcibly. | 01-26-2012 |
20120027435 | IMAGE FORMING APPARATUS - An image forming apparatus includes a two-component developing devices for each of a plurality of photoreceptors and a motor for the developing device. A transmission can assume a coupled state where the transmission transmits driving force of the motor to the developing device and a separated state where the transmission does not transmit the driving force of the motor to the developing device. A toner agitating mechanism stirs toner inside the developing device. A permeability sensor detects permeability inside the developing device and outputs a signal according to a ratio of the toner to the carrier. A coupling judging section judges that the coupling state exists when a variation of a signal value outputted by the permeability sensor equals or exceeds a predetermined value and judges that the separated state exists when the variation of the signal value outputted by the permeability sensor is lower than the predetermined value. | 02-02-2012 |
20120170948 | Developing device including toner concentration sensor and image forming apparatus including the developing device - A developing device using a two-component developing agent including a toner and a carrier. The developing device includes a toner concentration sensor which detects a concentration of a toner contained in the developing agent within the accommodation unit by using electrostatic capacity. The toner concentration sensor includes a frame combined with a housing that forms the accommodation unit, a measuring groove formed in the frame to be concave with respect to an inner surface of the housing so that the developing agent conveyed by the agitator is flowed into the measuring groove, and a pair of opposite electrodes disposed on the measuring groove. | 07-05-2012 |
20120170949 | IMAGE FORMING APPARATUS AND TONER REPLENISHING METHOD - An image forming apparatus, comprising, an exposure portion to expose a surface of an image carrier to form an electrostatic latent image; a developing device which includes an agitating roller to agitate developer, a developing roller to transfer toner of the developer on a surface of the image carrier and a toner concentration sensor to detect a toner concentration, said developing device developing the electrostatic latent image formed on the image carrier to form a toner image; a drive source to independently drive to rotate the developing roller and the agitating roller; and a control unit to control the drive source to change a rotational frequency of at least one of the developing roller and the agitating roller depending on the toner concentration detected by the toner concentration sensor. | 07-05-2012 |
20120207492 | DEVELOPMENT DEVICE, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS INCORPORATING SAME - A development device includes a developer container for containing developer, a developer bearer to carry by rotation the developer contained in the developer container to a development range facing a latent image bearer, a partition dividing the developer container into an upper compartment and a lower compartment arranged vertically, an upper developer conveyance member disposed in the upper compartment, a lower developer conveyance member disposed in the lower compartment, a communication portion through which the developer moves from the lower compartment to the upper compartment, disposed in a downstream end portion of the lower compartment in a direction in which the lower developer conveyance member transports the developer, and a toner concentration detector to detect a concentration of toner in the developer beneath the communication portion inside the lower compartment. | 08-16-2012 |
20120301160 | IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD - An image forming apparatus having a system speed of from 400 to 1,700 mm/sec, including a latent image bearer; an image developer developing the latent image with two-component developer including a toner and a carrier; a transferer, a toner concentration detector; a toner feeder; and a controller, wherein the toner comprises a release agent and a binder resin including a crystalline polyester resin and an amorphous resin, wherein a ratio (W/R) of a maximum rising peak height (W) of the crystalline polyester resin to a maximum rising peak height (R) of the amorphous resin, which are observed respective infrared absorption spectra when measured by an IR spectroscopy using a Fourier transform infrared spectroanalyzer, is from 0.22 to 0.55. | 11-29-2012 |
20130071131 | IMAGE FORMING APPARATUS CAPABLE OF STABILIZING IMAGE DENSITY ON A SHORT-TERM AND LONG-TERM BASIS - An image forming apparatus capable of stabilizing image density on a long-term basis by compensating for an error in prediction of toner particle charge amount, while reducing variation in image density on a short-term basis by the prediction. A CPU predicts an amount of electrostatic charge of toner particles in a developer container and sets an exposure condition and causes a toner image to be fixed on a recording medium and a pattern image for detecting image density, to be each formed on a photosensitive drum according to the set exposure condition, while performing gradation correction based on the gradation conversion table. The CPU updates the gradation conversion table such that a detected density of the pattern image becomes closer to a target density. The CPU sets the exposure condition based on a result of the prediction such that toner image density becomes constant. | 03-21-2013 |
20130164002 | CONTROL APPARATUS AND METHOD, IMAGE FORMING APPARATUS AND SYSTEM, AND COMPUTER READABLE MEDIUM - A control apparatus includes the following elements. A toner density specifying unit specifies a toner density in a developer stored in a developing device. A toner density controller performs control such that the toner density approximates a predetermined toner density target value. A first calculator calculates a first value corresponding to an image density of an image to be output after a first timing. A correction amount specifying unit specifies a correction amount for the toner density target value at the first timing. When the condition that an absolute value of a difference between the first value and a second value is greater than a predetermined threshold is satisfied, the correction amount specifying unit specifies a smaller correction amount for the toner density target value, compared with when the condition is not satisfied. A correcting unit corrects the toner density target value on the basis of the correction amount. | 06-27-2013 |
20140056603 | IMAGE FORMING APPARATUS - An image forming apparatus includes a latent image carrier, a container that contains a developer including a toner, developer transport members disposed so that peripheral surfaces thereof face the latent image carrier, a power supply that supplies voltages to the developer transport members, a detector that detects a toner concentration of the developer, and a controller. The controller performs control so that the power supply supplies to the developer transport members, when the toner concentration detected by the detector is higher than a predetermined upper limit, voltages having waveforms that generating a potential difference therebetween that causes the toner concentration of the developer distributed to a most downstream developer transport member to decrease and the toner concentration of the developer distributed to at least one of the developer transport members that is disposed upstream of the most downstream developer transport member to increase. | 02-27-2014 |
20140126921 | DEVELOPING APPARATUS AND IMAGE FORMING APPARATUS - A developing apparatus includes a development unit configured to supply toner to a photoconductor on which an electrostatic image is formed, a supply unit configured to supply toner to the development unit, a sensor configured to detect a concentration of toner in the development unit, and a control unit. The control unit is configured to, when the detected concentration of the toner is lower than a first value, control the supply unit to perform a toner supply process, control the sensor to detect the concentration of the toner after the toner supply process, count the number of times the sensor detects the concentration of the toner to be higher than a second value that is higher than the first value, and control the supply unit to repeat the toner supply process, when the counted number is less than a predetermined number that is equal to or greater than two. | 05-08-2014 |
20140301747 | DEVELOPMENT DEVICE, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS INCORPORATING SAME, AND DEVELOPER AMOUNT ADJUSTMENT METHOD THEREFOR - A development device is operable in multiple different speed modes and includes a developer bearer to carry developer, a developer regulator to adjust an amount of developer carried on the developer bearer, and multiple developer conveyance members disposed facing the developer bearer to transport developer in a longitudinal direction to circulate developer inside the development device. The multiple developer conveyance members including a first developer conveyance member to supply developer to the developer bearer and a second developer conveyance member to transport developer collected from the developer bearer. The development device executes developer amount balance adjustment in which a driving velocity of at least the multiple developer conveyance members is increased from a driving velocity in a lower-speed mode for a predetermined period after image development in the lower speed mode is completed and before image development in a higher speed mode is started. | 10-09-2014 |
20140376933 | MOVABLE BODY DRIVE METHOD AND SYSTEM, PATTERN FORMATION METHOD AND APPARATUS, EXPOSURE METHOD AND APPARATUS FOR DRIVING MOVABLE BODY BASED ON MEASUREMENT VALUE OF ENCODER AND INFORMATION ON FLATNESS OF SCALE, AND DEVICE MANUFACTURING METHOD - A drive unit drives a wafer stage in a Y-axis direction based on a measurement value of an encoder that measures position information of the wafer stage in the Y-axis direction and based on information on the flatness of a scale that is measured by the encoder. In this case, the drive unit can drive the wafer stage in a predetermined direction based on a measurement value after correction in which a measurement error caused by the flatness of the scale included in the measurement value of the encoder is corrected based on the information on the flatness of the scale. Accordingly, the wafer stage can be driven with high accuracy in a predetermined direction using the encoder, without being affected by the unevenness of the scale. | 12-25-2014 |
20150010315 | IMAGE FORMING DEVICE - An image forming device includes: a developing device which includes a developing unit storing a developer containing a first carrier and a toner and a toner concentration detection unit detecting a toner concentration within the developing unit; and a supply container which stores a supply developer containing a second carrier and the toner, and supplies, based on a detection value by the toner concentration detection unit, the supply developer to the developing unit and discharges an excessive amount of the developer within the developing unit from the developing unit. Then, the setting value of the toner concentration detection unit is corrected based on the presence proportion of the second carrier within the developing unit detected by a calculation unit. | 01-08-2015 |
20150050036 | IMAGE FORMING APPARATUS - An image forming apparatus includes: an image bearing member; a developing device; a supply device which supplies toner to the developing device; a density detector which detects information about a toner density as a ratio of toner and carrier of the developer of the developing device; and a controller which interrupts an image forming operation and is capable of executing a forced supply mode of performing the toner supply to the developing device from the supply device, based on first information of at least one of detection results of the density detector and information about a toner consumption, second information about the amount of supply operation supplied by the supply device, in which the controller determines whether or not to execute the forced supply mode, and third information about an accumulated value of the amount of toner consumption after the forced supply mode executed last time. | 02-19-2015 |
20150063843 | TONE CORRECTION PROCESS THAT CORRECTS TONE OF IMAGE FORMED BY IMAGE FORMING APPARATUS - An image forming unit forms an electrostatic latent image on an image carrier based on image data converted by a conversion unit, and the image is developed by a developing portion using toner. A replenishment control unit controls an amount of the toner with which the developing portion is replenished based on a toner density in the developing portion so that the toner density in the developing portion reaches a target density. A first determination unit determines a target density based on a result of a first measurement image being measured. A correction unit corrects conversion conditions based on a result of measuring a second measurement image and a correction condition. A second determination unit determines the correction condition based on the target density determined by the first determination unit. | 03-05-2015 |
20150086229 | DEVELOPING DEVICE, IMAGE FORMING APPARATUS AND TONER CONCENTRATION DETECTING METHOD - A developing device includes multiple developing units, and multiple toner concentration sensors. The multiple developing units contain respective developers. The multiple toner concentration sensors have respective LC oscillator circuits and are disposed at the respective multiple developing units. A capacitor constituting the LC oscillator circuit differs in capacitance at each of the toner concentration sensors installed on the multiple developing units. | 03-26-2015 |
20150117880 | IMAGE FORMING APPARATUS - An image forming apparatus which prohibits an image forming operation based on a detection result of a remaining amount detecting unit, thereafter immediately allows the image forming operation based on a detection result of a replacement detecting unit, performs a supply restriction mode which restricts a toner supply amount such that a toner supply amount in a predetermined initial period after allowance of an image forming is smaller than a normal mode in a case where a detection result of a toner density detecting unit and a target value are under same conditions, respectively. | 04-30-2015 |
20150331355 | Image Forming Apparatus That Calculates Toner Concentration in Developer - An image forming apparatus includes an image carrier, a developing roller, and a control unit. The image carrier has a surface on which an electrostatic latent image is formed. The developing roller is arranged to face the image carrier to form a development nip between the image carrier and the developing roller. The developing roller supplies toner in a two-component developer carried on a surface of the developing roller to the image carrier in the development nip so as to develop the electrostatic latent image. The control unit drivingly controls the image carrier and the developing roller. The control unit discharges the toner in the development nip to the image carrier in a state where the developing roller is stopped, so as to calculate a toner concentration in the two-component developer based on an amount of discharged toner. | 11-19-2015 |
20150355572 | DEVELOPING DEVICE, IMAGE FORMING APPARATUS, AND PROCESS CARTRIDGE - 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. | 12-10-2015 |
20160041494 | DEVELOPMENT DEVICE, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS INCORPORATING SAME, AND DEVELOPER AMOUNT ADJUSTMENT METHOD THEREFOR - A development device is operable in multiple different speed modes and includes a developer bearer to carry developer, a developer regulator to adjust an amount of developer carried on the developer bearer, and multiple developer conveyance members disposed facing the developer bearer to transport developer in a longitudinal direction to circulate developer inside the development device. The multiple developer conveyance members including a first developer conveyance member to supply developer to the developer bearer and a second developer conveyance member to transport developer collected from the developer bearer. The development device executes developer amount balance adjustment in which a driving velocity of at least the multiple developer conveyance members is increased from a driving velocity in a lower-speed mode for a predetermined period after image development in the lower speed mode is completed and before image development in a higher speed mode is started. | 02-11-2016 |
20160041503 | DEVELOPING DEVICE PROVIDED WITH TONER CONCENTRATION DETECTION SECTION AND IMAGE FORMING APPARATUS PROVIDED WITH SAME - A developing device includes: a container, a stirring member, a developing roller, a toner concentration detection section, a stirring plate, and a blade. The stirring plate is attached to the rotary shaft of the stirring member in a manner such as to be rotatable together with the rotary shaft, and has a tip part located in the radial direction at a predefined distance from the detection surface. The blade has elasticity, is attached to the stirring plate in a manner such as to surround a one-side surface, an another-side surface, and the tip part in a rotation direction of the stirring plate, has a sufficient length in the radial direction enough to abut the detection surface, and makes sliding-contact with the detection surface while rotating together with the stirring plate. | 02-11-2016 |
20160147174 | IMAGE FORMING APPARATUS - An image forming apparatus includes a latent image bearer; a developing device containing two-component developer and including a developer bearer, a development voltage source, and a toner concentration detector; a toner supply device to supply toner to the developing device; a transfer device; and a controller to keep a toner concentration in the developer in the developing device at a target toner concentration during image formation. The controller executes forced toner consumption in which the developing device supplies the toner to the latent image bearer the toner at a predetermined forced toner consumption timing, while inhibiting the toner supply device from supplying toner. When the toner concentration falls to a prescribed toner density lower than the target toner concentration, the controller completes the forced toner consumption and executes a post-consumption toner supply operation. | 05-26-2016 |
20160378039 | DEVELOPING DEVICE, AND IMAGE FORMING APPARATUS AND PROCESS CARTRIDGE INCORPORATING SAME - A developing device includes a developer bearer disposed opposite an image bearer and configured to rotate and carry developer to a latent image on the image bearer, a developer container to contain the developer, a detector including a detecting portion to detect a density of toner in the developer in the developer container, a wire connected to the detector, and a wire holder to hold the wire and determine a position of the wire relative to the detector. | 12-29-2016 |