Patent application number | Description | Published |
20080267640 | Image Forming Apparatus - An image forming apparatus, according to the present invention can include, an image carrier, a charger configured to charge the image carrier, an exposure unit configured to form an electrostatic latent image by exposing the image carrier, a developing unit configured to develop the electrostatic latent image, a detection unit configured to detect the density of a developer adherent to the image carrier, and a controller configured to determine a deteriorated state of the image carrier, by charging the image carrier and then conducting a development, in a condition where a potential difference between the charger and the developing unit is set to be smaller than that at the time of image formation, before detecting a density of a developer on an unirradiated portion on the image carrier, so that a detection result to be used for its decision of the deteriorated state of the image carrier is obtained. | 10-30-2008 |
20090010661 | Image Forming Apparatus - An image forming apparatus includes: a plurality of photosensitive members; a plurality of discharging units respectively facing the plurality of photosensitive members; a plurality of high-voltage power supply units which are provided for the plurality of charging units and supply power to the plurality of discharging units; a discharge detection unit that detects abnormality in the plurality of discharging units; a controller which controls the output of one of the high-voltage power supply units having the largest output to be smaller when the discharge detection unit detects abnormality; and a determination unit which, in a state where the controller controls the output of the one of the high-voltage power supply unit, determines whether abnormality occurs in the discharging unit corresponding to the one of the high-voltage power supply unit based on the detection state of the discharge detection unit. | 01-08-2009 |
20090027924 | Feedback Control Device - A feedback control device is provided. The feedback control device includes a controlled-system which outputs and output in correspondence with a control signal; a feedback signal generating member which generates a feedback signal as the output of the controlled-system; a reference signal unit which outputs a reference control signal to the controlled-system; and a determination unit which determines a version of the controlled-system on the basis of the feedback signal generated by the feedback signal generating member when the reference signal unit outputs the reference control signal to the controlled-system. | 01-29-2009 |
20090060535 | IMAGE FORMING APPARATUS - An image forming apparatus is provided. The image forming apparatus includes: a photosensitive member; a discharging unit arranged to face the photosensitive member; a high-voltage power supply unit which supplies power to the discharging unit; a discharge detection unit which detects abnormal discharge in the discharging unit; an output controller which controls an output of the high-voltage power supply unit according to control information; and a cleaning detection unit which compares current control information for the high-voltage power supply unit supplying power to the discharging unit in which abnormal discharge is detected with previous control information for the high-voltage power supply unit when previous abnormal discharge is detected in the discharging unit, and which detects whether the discharging unit has been cleaned based on the comparison result. | 03-05-2009 |
20090245817 | Image Forming Apparatus - An image forming apparatus has: an image forming unit which is configured to scan a laser beam in a main scanning direction to expose a photosensitive member, and which forms an electrostatic latent image on the photosensitive member to form an image; a process cartridge that is detachably mounted within the image forming apparatus, the process cartridge holding the photosensitive member on which the electrostatic latent image is formed, and configured to develop the electrostatic latent image by supplying toner to the electrostatic image; and an origin detection unit that is provided on the process cartridge in a position lying within a range of an optical path of the laser beam and out of a range of an optical path of the laser beam for forming the electrostatic latent image, the origin detection unit configured to detect an origin of the laser beam for scanning and exposing. | 10-01-2009 |
20090245829 | Image Forming Apparatus - An image forming apparatus comprises an image carrier configured to hold a developing agent image; a transfer unit that transfers the developing agent image to a recording medium; a first application unit that controls a transfer voltage applied to the transfer unit; a recovery unit that recovers the developing agent remaining on the image carrier; a second application unit that controls a recovery voltage applied to the recovery unit; a determination unit that determines whether or not a recovery current flowing between the image carrier and the recovery unit exceeds a first predetermined current value; and a control unit that, when the determination unit makes a positive determination that the recovery current has exceeded the first predetermined current value, performs a protective control for controlling the first application unit such that a transfer current flowing between the image carrier and the transfer unit becomes greater. | 10-01-2009 |
20090262374 | Image Forming Apparatus - An image forming apparatus is provided. A first cleaning unit is configured to collect a particle deposited on an object. An applying unit is configured to apply a voltage to the first cleaning unit. A first detector is configured to detect a first current flowing between the first cleaning unit and the object A controller is configured to control the applying unit. When the detected first current becomes equal to or greater than a first predetermined value, the controller controls the applying unit to reduce the voltage applied to the first cleaning unit so as to make the first current smaller than the first predetermined value. | 10-22-2009 |
20090295352 | Power Supply Unit and Image Forming Apparatus Including the Same - A power supply unit is provided. An output generation circuit generates an output corresponding to an supplied drive signal and supplies the output to a load. A detection circuit receives the output and generates a detection signal in response to the output. A control circuit generates a digital control signal for controlling a value of the output toward a target value in response to the detection signal. A first D/A conversion circuit receives the digital control signal and converts the digital control signal into an analog control signal, the first D/A conversion circuit being capable of setting a reference range for defining a voltage range of the analog control signal. A driving circuit generates the drive signal in response to the analog control signal and supplies the drive signal to the output generation circuit. A range switching circuit switches the reference voltage range of the first D/A conversion circuit between a wide range and a narrow range narrower than the wide range. | 12-03-2009 |
20100034552 | IMAGE FORMING DEVICE - There is provided an image forming device, comprising: a first electrical load; a second electrical load; a voltage generation circuit that generates a second voltage to be applied to the second electrical load; a shunt circuit that located between an output side of the voltage generation circuit and the first electrical load; and a controller that executes first control of controlling the shunt circuit to change a first voltage applied from the shunt circuit to the first electrical load to a first target level, and second control of controlling the voltage generation circuit to change the second voltage to a second target level. The controller executes voltage change suppression control of controlling the second voltage such that change of the second voltage becomes gentler as a difference between the first voltage and the first target level becomes larger. | 02-11-2010 |
20100052873 | POWER SUPPLY EMPLOYING PULSE-WIDTH MODULATION AND DIGITAL-TO-ANALOG CONVERTER, POWER SUPPLY CONTROL DEVICE, AND MANUFACTURING METHOD OF THE SAME - A power supply for supplying electric power comprises a power circuit which supplies L channels of electric power (L: positive integer), a control circuit board which outputs multiple types of control signals including a digital control signal and a PWM signal, a digital-to-analog converter having M channels (M: positive integer less than L) each of which converts the digital control signal into an analog control signal, and N demodulation circuits (N=L−M) each of which generates an analog control signal by demodulating the PWM signal. The control circuit board is electrically connected to the power circuit via the M channels of the digital-to-analog converter and the N demodulation circuits. N is a positive integer not more than M. | 03-04-2010 |
20100196043 | Power Supply Circuit Identification Device for Identifying a Type of a Power Supply Circuit and Image Forming Apparatus - A power supply circuit identification device for identifying a type of a power supply circuit, the power supply circuit having an input terminal to which a control signal for controlling electrical power supplied to an electrical load is input and an output terminal from which a detection signal that indicates whether the electrical power corresponding to the control signal is supplied to the electrical load is output, at least one of the input terminal and output terminal being plurally provided and having a type-dependent correlation between the input and output terminals. The identification device includes: a control section configured to input the control signal to the power supply circuit via the input terminal; a reading section configured to read the detection signal from the output terminal; and an identification section configured to identify a type of the power supply circuit based on a reading result from the reading section. | 08-05-2010 |
20100278547 | Image Forming Apparatus and Voltage Applying Device - An image forming apparatus includes a voltage applying unit for applying a voltage to an electric load; a sub control unit for controlling the voltage applying unit; a restarting unit for restarting the sub control unit in response to receipt of a restart signal; a determining unit for determining whether or not restart of the sub control unit is abnormal restart; and a main control unit. The main control unit generates a control start signal for allowing the voltage applying unit to start generation of the voltage, and the restart signal. When the determining unit determines that restart of the sub control unit is abnormal restart, the main control unit sends again the control start signal to the sub control unit. | 11-04-2010 |
20110026949 | Image Forming Apparatus and Method for Testing the Same - An image forming apparatus includes: an attachment unit configured to receive at least one voltage and being replaceable with a test tool, a controller for controlling operation of a plurality of voltage generating circuits, a current detecting section and a deciding section. The controller is configured to control a first voltage generating circuit so as to generate a test voltage and so as to apply the test voltage through a first voltage line, the test tool, and a second voltage line to a second voltage generating circuit. The deciding section is configured to, upon a detection current corresponding to the applied test voltage and detected by the current detecting section being equal to or greater than a first predetermined value, decide that the predetermined voltages are to be normally applied through the respective first and second voltage lines to the attachment unit. | 02-03-2011 |
20120027436 | Image Forming Apparatus - An image forming apparatus including: a plurality of photosensitive drums; a plurality of scorotron chargers provided for the plurality of photosensitive drums, respectively, a voltage application circuit commonly connected to the plurality of scorotron chargers, a plurality of wires provided for the plurality of scorotron chargers, respectively; a plurality of grid electrodes provided for the plurality of scorotron chargers, respectively; at least one of current detecting units provided for at least one of the plurality of grid electrodes, respectively, and at least one of the current detecting units detecting grid current which flows into at least one of the grid electrodes, respectively; and a control device configured to control the voltage application circuit such that at least one of the grid currents detected by at least one of the current detecting units become equal to or higher than a reference value. | 02-02-2012 |
20120027437 | Image Forming Apparatus - An image forming apparatus, includes: at lease one photosensitive element; a plurality of chargers configured to charge the at lease one photosensitive element; a voltage applying circuit commonly connected to the plurality of chargers and configured to apply a voltage to the plurality of chargers; a current detecting unit configured to detect a current sum of current that flows to the plurality of chargers from the voltage applying circuit; and a control device configured to control the voltage applying circuit so that the current sum detected by the current detecting unit becomes equal to or larger than a reference value. | 02-02-2012 |
20120134699 | IMAGE FORMING APPARATUS - An image forming apparatus is provided, which includes an image forming unit configured to form an image on a recording medium, a cleaned body that is an intended body to be cleaned, a cleaning member configured to clean at least attached matter, which is generated in image formation by the image forming unit, on the cleaned body, a backup member disposed to face the cleaning member across the cleaned body, a voltage supply unit configured to supply the backup member with a cleaning voltage having a polarity identical to a charge polarity of the attached matter, in an operation of cleaning the cleaned body, a detector configured to detect an electric quantity of the cleaning member when the cleaning voltage is supplied to the backup member by the voltage supply unit, and a controller configured to control the detected electric quantity of the cleaning member to be a predetermined value. | 05-31-2012 |
20130177326 | Image Forming Apparatus Capable of Electrically Detecting Usage State of Process Cartridge Mounted Therein - An image forming apparatus includes: a process cartridge; a voltage applying unit; a contact; an electric line; a detection unit; and a control unit. The voltage applying unit generates a voltage and applies the voltage to the process cartridge. The contact is switched an ON state and an OFF state based on a usage state of the process cartridge The electric line electrically connects the voltage applying unit to the process cartridge. The detection unit is electrically connected to the electric line via the contact and provides either one of a first detection output corresponding to the ON state and a second detection output corresponding to the OFF state. The control unit executes a determination process in a determination mode for determining the usage state of the process cartridge based on either one of the first detection output and the second detection output of the detection unit. | 07-11-2013 |
20130322911 | IMAGE FORMING APPARATUS - An image forming apparatus is configured to electro-photographically form an image and includes a main body frame which includes a side wall, an outer cover which covers an outer face of the main body frame, a high-voltage board which includes a high-voltage generator circuit configured to generate a high voltage and supply an electric power to a device requiring a high-voltage power source, and a main board which includes a main control circuit configured to perform a control on an image forming process of the image forming apparatus. In a side region which is formed by the side wall of the main body frame and the outer cover, the high-voltage board and the main board are disposed along the side wall to overlap with each other at least partially, and the high-voltage board is disposed on an outer side relative to the main board. | 12-05-2013 |
20140079429 | IMAGE FORMING APPARATUS - An image forming apparatus includes a power supply circuit, at least one motor configured to receive electric power from the power supply circuit, a photosensitive body configured to be rotated by the motor for forming an image on a sheet, a charger configured to charge the photosensitive body, a high voltage generation circuit configured to receive electric power from the power supply circuit and generate a high voltage applied to the charger, and a control device. The control device is configured to determine whether a motor activation condition to activate the motor is satisfied, determine whether a limitation condition to limit a peak of a current output from the power supply circuit is satisfied, and regulate the current flowing through the high-voltage generation circuit if the motor activation condition and the limitation condition are satisfied. | 03-20-2014 |
20140241743 | Image Forming Apparatus - An image forming apparatus is provided. The image forming apparatus includes a plurality of photosensitive members arranged to align in parallel with one another, an exposure device arranged in an upper position with respect to the plurality of photosensitive members and configured to expose the photosensitive members to light, an exposure controller arranged in an upper position with respect to the exposure device and configured to control the exposure device according to inputted image data, a power board, arranged in a lower position with respect to the plurality of photosensitive members and configured to convert alternate current power to direct current power, and a voltage converter arranged in un upper position with respect to the exposure device and configured to convert the direct current power supplied from the power board into an at least single-leveled first voltage and supply the first voltage to the exposure controller. | 08-28-2014 |