Abstract: For moisture detection and prevention systems, the reduction or prevention of false positive and false negative alarms is of immense economic value. A method of discriminating the types of materials in contact with a capacitive detector can be easily implemented even for battery-powered devices and has already proven useful in testing in preventing false alarms, and discriminating various solutions.

Abstract: A control circuit of an image forming apparatus outputs a pulse signal. A clock signal generation circuit generates a clock signal, based on the pulse signal. A pulse signal conversion circuit generates a pulse conversion control signal of a voltage value associated with a duty ratio of the pulse signal. An AC voltage generation circuit generates an AC voltage of a frequency based on the clock signal. Either the AC voltage generation circuit or a DC voltage generation circuit generates a voltage whose amplitude or voltage value increases as a voltage value of the received pulse conversion control signal increases, and whose amplitude or voltage value decreases as a voltage value of the pulse conversion control signal decreases.

Abstract: An image forming apparatus includes a photosensitive member, a corona charger including a discharging electrode and a grid electrode having a surface layer containing carbon atoms as a main component and configured to electrically charge the photosensitive member under application of a voltage to the discharging electrode and the grid electrode, and an output portion configured to output information on a lifetime of the grid electrode. The output portion outputs the information on the basis of an index value of an amount of use of the grid electrode correlating with a product of a value of a grid current flowing through the grid electrode and a time of flowing of the grid current through the grid electrode.

Abstract: An image forming apparatus includes a unit, a high-voltage board and a connecting mechanism. The connecting mechanism includes a first connecting member, a first holding member, a coupling member and a second connecting member. The first connecting member includes a first spring terminal. The first spring terminal includes a first large diameter part and a first small diameter part. The first holding member has a first contact part coming into contact with an end part of the first small diameter part at a side of the first large diameter part in a state where the first holding member is coupled with the coupling member. The coupling member has a second contact part coming into contact with an end part of the first large diameter part at a side of the first small diameter part in the state where the first holding member is coupled with the coupling member.

Abstract: An image forming apparatus includes a transfer device to transfer a toner image from an image bearing member onto a recording medium, disposed opposite the image bearing member, a transfer bias power source to apply, between the image bearing member and the transfer device, a superimposed transfer bias in which a direct current (DC) component and an alternative current (AC) component are superimposed to transfer the toner image borne on the image bearing member to the recording medium, and a controller to change the superimposed bias that the transfer bias power source applies. The controller changes the levels of the DC component and the AC component of the superimposed transfer bias in a color mode from that in a monochrome mode to secure a return electric field in the superimposed transfer bias by which the toner is returned from the recording medium to the image bearing member.

Abstract: A high-voltage power source includes a high-voltage power source unit configured to apply high voltage obtained by superposing a high alternating-current voltage on a high direct-current voltage to a charging member, an output unit configured to output a first direct-current voltage having a first voltage value according to an externally input pulse-width modulation signal, a direct-current voltage conversion unit configured to convert the first direct-current voltage into a second direct-current voltage, a generation unit configured to boost the second direct-current voltage to generate a high direct-current voltage, a peak value detection unit configured to detect a positive peak value and a negative peak value from an alternating-current component of the high direct-current voltage, and a voltage difference output unit configured to output a third direct-current voltage having a third voltage value to the direct-current voltage conversion unit.

Abstract: An image forming apparatus performs first control, while rotating an image bearing member at a first speed during non-image-formation, to apply a plurality of alternating-current voltages differing in peak-to-peak voltage to a charging device and to detect the value of each alternating current flowing through the image bearing member. When rotating the image bearing member at a second speed during image formation, the image forming apparatus performs second control, while rotating the image bearing member at the second sped before the start of image formation, to apply an alternating-current voltage determined based on the first control to the charging device. In the second control, the image forming apparatus detects the value of the alternating current flowing through the image bearing member, and determines a peak-to-peak voltage of the alternating-current voltage applied to the charging device at the time of image formation based on the detected alternating current value.

Abstract: A conveying apparatus or an image forming apparatus includes: a housing including an opening and closing member that can be opened and closed; a conveying path that conveys an object to be conveyed, at least a part of the conveying path being provided adjacent to an inner side of the opening and closing member; a first detector that detects whether the object is present in a predetermined region and outputs a detection signal corresponding to a result of the detection; and an interlocking mechanism that causes, when the opening and closing member is opened, the first detector to change at least one of a position and a structure of the first detector in mechanically association with movement of opening of the opening and closing member, and to output a detection signal which is the same as a detection signal output when the object is present in the predetermined region.

Abstract: A high voltage power source device includes piezoelectric transformers, each of the piezoelectric transformers being formed with a primary electrode and a secondary electrode on piezoelectric ceramics, receiving a primary voltage at the primary electrode, and generating a second voltage from the secondary electrode, switching elements, each of the switching elements driving a respective one of the piezoelectric transformers, and primary voltage supply devices, each of the primary voltage supply devices supplying the primary voltage to the primary electrode of the respective one of the piezoelectric transformers by driving the respective one of the switching elements when the secondary voltage is generated from the respective one of the second electrodes, wherein the respective one of the primary voltage supply devices supplies the primary voltage to the respective one of the primary electrodes by driving the respective one of the switching elements at the same frequency.

Abstract: A high-voltage power source includes a high-voltage power source unit configured to apply high voltage obtained by superposing a high alternating-current voltage on a high direct-current voltage to a charging member, an output unit configured to output a first direct-current voltage having a first voltage value according to an externally input pulse-width modulation signal, a direct-current voltage conversion unit configured to convert the first direct-current voltage into a second direct-current voltage, a generation unit configured to boost the second direct-current voltage to generate a high direct-current voltage, a peak value detection unit configured to detect a positive peak value and a negative peak value from an alternating-current component of the high direct-current voltage, and a voltage difference output unit configured to output a third direct-current voltage having a third voltage value to the direct-current voltage conversion unit.

Abstract: An image forming apparatus includes a receiving unit configured to receive an input regarding a print process from a user; a setting unit configured to set the apparatus to normal or energy saving mode based on the input from the user, the normal mode causing the apparatus to be operated by the power supplied from a power supply unit, the energy saving mode causing the apparatus to be operated by the power supplied from the power supply unit or a secondary battery so that power consumption of the apparatus is less than that in the normal mode; a calculation unit configured to calculate a charging amount of the battery based on an energy saving time for which the apparatus has been in the energy saving mode; and a charging unit configured to charge the battery with the power from the power supply unit by the charging amount.

Abstract: A power supply system includes: capacitors connected to an alternating current power supply; a rectification circuit connected to the capacitors and rectifying an alternating current voltage applied to the capacitors; a signal generation circuit connected to an output line of the rectification circuit and configured to generate a detection signal corresponding to a zero cross point of an alternating current output; an electricity storage unit connected to the output line of the rectification circuit; a backflow regulation element provided on the output line of the rectification circuit and configured to regulate backflow of current; a current limit element configured to limit current flowing from the output line of the rectification circuit towards the electricity storage unit, and a control unit that is connected to the output line of the rectification circuit, and is configured to detect a zero cross point of the alternating current output.

Abstract: A power supply system includes: a switching power supply generating a voltage from an alternating current power supply; capacitors connected to the alternating current power supply; a rectification circuit configured to rectify an alternating current voltage applied to the capacitors; a backflow regulation regulating backflow of current from the switching power supply; a signal generation circuit generating a detection signal corresponding to a zero cross point of the alternating current power supply; a power supply line connected to the switching power supply and the rectification circuit; an electricity storage unit connected to the power supply line; a voltage limit element configured to limit a voltage of the output line of the rectification circuit, and a control unit, power being fed to the control unit through the power supply line. The control unit is configured to detect a zero cross point based on the detection signal.

Abstract: A changing voltage is applied to a first charging roller. A voltage obtained by superimposing an alternating voltage on a direct voltage is applied to a second charging roller disposed on the downstream side of the first charging roller in the rotation direction of a photosensitive member. During image formation, the changing voltage applied to the first charging roller is changed so that the magnitude relationship between the potential of the photosensitive member which has been charged by using the first charging roller and which has reached a position at which the photosensitive member is charged by using the second charging roller and the direct voltage applied to the second charging roller is alternately switched.

Abstract: The high-voltage power supply apparatus includes an inductor to be applied with a voltage when a driving unit is driven by a drive signal at a predetermined frequency, a rectification unit connected to both ends of the inductor, the rectification unit including multiple capacitors and multiple diodes, a current detection unit configured to detect a current flowing through the rectification unit, and a control unit configured to control a duty of the drive signal based on a result of detection by the current detection unit.

Abstract: In an image forming apparatus, a plurality of cartridges each of which includes a photoconductor and a charger configured to charge the photoconductor is detachably installable in a main body housing. Chargers are connected in parallel to a voltage application unit configured to apply a voltage to the chargers. A cartridge installation determination unit is configured to determine whether or not each of the cartridges is installed. Control over the voltage application unit exercised by a controller includes a constant-voltage control and a constant-current control. The controller is configured to execute the constant-voltage control upon startup of an initial operation for preparation of printing and to switch from the constant-voltage control to the constant-current control if the cartridge installation determination unit determines that all the cartridges are installed.

Abstract: There is described an image forming apparatus including an imaging member having a charge retentive-surface for developing an electrostatic latent image thereon, a substrate and a photoconductive member disposed on the substrate. A bias charge roller for applying an electrostatic charge on the charge retentive surface to a predetermined electric potential is included in the image forming apparatus. The bias charge roller includes a first circumferential area in contact with the photoconductive member (CC[contact]), and a second circumferential area (CC[non-contact]) spaced a distance of from 1 ?m to 1 mm from the photoconductive member. The image forming apparatus includes a power supply for supplying an oscillating voltage signal to the bias charge roller wherein the oscillating voltage signal has a frequency Am[fAC] and an amplitude Am[VAC]. The following relationship is met: (CC[contact]/CC[non-contact])?(Am[fAC]/Am[VAC])?(CC[non-contact]/CC[contact]) by the image forming apparatus.

Abstract: A bias power supply device includes: a temperature detecting unit; a control signal generation unit generating and outputting an output frequency setting signal for setting a frequency of an alternating current power in accordance with a repetition frequency and a resonance frequency signal being set at a lower or higher repetition frequency according to the measured temperature; a waveform signal generation circuit generating a waveform signal for pulse-width modulation having a time constant for rising set by capacity and resistance based on the resonance frequency signal; a modulation circuit generating a pulse-width-modulated modulation signal based on the waveform signal and the output frequency setting signal; a switching circuit driven by the modulation signal; and a transformer having a first winding and a second winding, and supplying an alternating current power with a repetition frequency of the output frequency setting signal to an external load connected to the second winding.

Abstract: 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.

Abstract: There is described an image forming apparatus including an imaging member having a charge retentive-surface for developing an electrostatic latent image thereon, a substrate and a photoconductive member disposed on the substrate. A bias charge roller for applying an electrostatic charge on the charge retentive surface to a predetermined electric potential is included in the image forming apparatus. The bias charge roller includes a first circumferential area in contact with the photoconductive member (CC[contact]), and a second circumferential area (CC[non-contact]) spaced a distance of from 1 ?m to 1 mm from the photoconductive member. The image forming apparatus includes a power supply for supplying an oscillating voltage signal to the bias charge roller wherein the oscillating voltage signal has a frequency Am[fAC] and an amplitude Am[VAC]. The following relationship is met: (CC[contact]/CC[non-contact])?(Am[fAC]/Am[VAC])?(CC[non-contact]/CC[contact]) by the image forming apparatus.

Abstract: An image forming apparatus having; image supporting members provided for a plurality of colors; chargers to be impressed with charging biases to charge the respective image supporting members; developing devices to be impressed with developing biases to develop latent images formed on the image supporting members; a charging bias power supply, including high-voltage DC power supply circuits and an AC power supply circuit, for applying the charging biases, which are generated by superposition of direct-current voltages and an alternate-current voltage, to the chargers; and a control circuit that performs stop processing to stop applications of the charging biases and the developing biases.

Abstract: A power supply circuit includes a voltage regulator to which a first high voltage is supplied, to operate at constant voltage and regulate the supplied first high voltage, and a first rectifier circuit to which the first high voltage is supplied, connected in parallel to the voltage regulator, to rectify the supplied first high voltage for output as a first DC voltage. When the first high voltage is a pseudo-alternating-current (AC) voltage consisting of two types of high voltages that alternate, the voltage regulator regulates each of the two different types of the voltages to output a desired pseudo-AC voltage.

Abstract: An image forming apparatus that forms a color image by overlaying toner images formed on respective first, second, and third photoreceptors, comprising: first, second, and third voltage-applied members respectively facing the first, second, and third photoreceptors; a first AC power supply generating first AC voltage, and superimposing the first AC voltage on first DC voltage to generate first voltage for causing a first electric field between the first voltage-applied member and the first photoreceptor; a second AC power supply generating second AC voltage, and superimposing the second AC voltage on second DC voltage to generate second voltage for causing a second electric field between the second voltage-applied member and the second photoreceptor; and a composite circuit superimposing a composite of the first voltage and the second voltage on third DC voltage, to generate third voltage for causing a third electric field between the third voltage-applied member and the third photoreceptor.

Abstract: An image processing apparatus includes an image-processing designating unit that allows a user to designate predetermined image processing to be applied to image data for generating a preview image that represents a state of an output image before image output; a preview-image generating unit that generates a preview image in accordance with the designated image processing; a preview-image display unit that displays the preview image generated by the preview-image generating unit; and a display-mode switching control unit that, when the preview image is displayed, switches to a display mode with an enhanced viewability relative to a power-saving display state in accordance with a content of the designated image processing.

Abstract: An image forming apparatus including a rotatable photosensitive member, a first charging member for electrically charging the photosensitive member at a first charging portion by applying thereto a first DC voltage, and a second charging member, provided downstream of the first charging portion with respect to a rotational direction of the photosensitive member, for electrically charging the photosensitive member charged by the first charging member, at a second charging portion by applying thereto an oscillating voltage in the form of a second DC voltage superposed with an AC voltage.

Abstract: An image forming apparatus includes: a first photosensitive member; a second photosensitive member; a third photosensitive member; a first scorotron-type charger that is configured to charge the first photosensitive member; a second scorotron-type charger that is configured to charge the second photosensitive member; a third scorotron-type charger that is configured to charge the third photosensitive member; a first voltage applying circuit, which is connected to the first scorotron-type charger, and which is configured to apply a voltage to the first scorotron-type charger; and a second voltage applying circuit, which is commonly connected to the second scorotron-type charger and the third scorotron-type charger, and which is configured to apply a voltage to the second scorotron-type charger and the third scorotron-type charger.

Abstract: An image forming apparatus that can prevent image deletion in carrying out image formation upon turning-on of power supply after main power supply is turned off before the image forming apparatus goes into a sleep state. A movable member is moved between a shielding position at which it shields a photosensitive drum from a charger and a retracting position at which the photosensitive drum and the charger are opened to each other. When power supply is turned on, a time period for which the photosensitive drum is rotated by a driving unit is controlled according to the position of the movable member detected by a movable member sensor.

Abstract: A rotary developing device that rotates about a rotational axis includes plural developing units, an energized member, a hollow cylindrical unit, a first energizing member, a rotatable unit, a second energizing member, a first conductive member, and a second conductive member. Each developing unit develops a latent image formed on an image holding member into a visible image, and is rotatable about the rotational axis so as to be sequentially movable to a developing position facing the image holding member. The hollow cylindrical unit is arranged along the rotational axis. The rotatable unit is supported rotatably with respect to the hollow cylindrical unit. One end of the first conductive member is connected to the first energizing member supported on an outer periphery of the hollow cylindrical unit. The second conductive member connects the second energizing member supported by the rotatable unit to the energized member supported in a developing unit.

Abstract: The high-voltage output apparatus includes a voltage application part that applies a DC voltage to the charge member; a current detection part that detects a value of a current flowing in the image bearing member when the DC voltage is applied to the charge member; and a control part that calculates a plurality of discharge start voltages for the image bearing member, based on a plurality of current values detected by the current detection part as a result of the voltage application part applying a plurality of different DC voltages to the charge member, and controls the DC voltage applied to the charge member, using the plurality of calculated discharge start voltages. Consequently, a high-quality image can be formed by maintaining a potential on a photosensitive drum to be constant irrespective of the states of the circumstances and/or the drum layer thickness.

Abstract: A cartridge detachably mountable to a main assembly of an image forming apparatus, the main assembly including a main assembly electrical contact, includes a roller including an electroconductive shaft, the roller being rotatable with the shaft; and a supporting member rotatably supporting the shaft and provided with a hole portion for exposing a part of a surface of a longitudinal end of the shaft to directly contact the part to the main assembly electrical contact and an end surface positioning portion for determining a position of the end surface with respect to a longitudinal direction of the shaft by contacting another part of the end surface.

Abstract: A charging device includes a charging member in contact with or adjacent to a charged body, a charge housing that holds the charging member, bearing members that rotatably support the charging member, at least one of the bearing members being a conductive bearing member, pressing members that press the bearing members toward the charged body, at least the pressing member for the conductive bearing member being formed of a conductive material, a platelike power supply member in contact with the pressing member for the conductive bearing member, and positioning mechanisms that position the bearing members. The power supply member has a platelike extending portion. The positioning mechanism provided on a power supplied side of the charging member includes a positioning portion provided in the conductive bearing member, and a positioned portion provided in the extending portion. The positioned portion engages with the positioning portion when the extending portion elastically deforms.

Abstract: 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.

Abstract: There is provided an image forming apparatus which includes multiple charging rollers and which can suppress accumulation of deposits such as external additives onto a charging roller without reducing productivity of the image forming apparatus. A changing voltage is applied to a first charging roller. A voltage obtained by superimposing an alternating voltage on a direct voltage is applied to a second charging roller disposed on the downstream side of the first charging roller in the rotation direction of a photosensitive member. During image formation, the changing voltage applied to the first charging roller is changed so that the magnitude relationship between the potential of the photosensitive member which has been charged by using the first charging roller and which has reached a position at which the photosensitive member is charged by using the second charging roller and the direct voltage applied to the second charging roller is alternately switched.

Abstract: A high-voltage power supply for an image forming apparatus compares a detected output voltage generated by dividing a high-voltage output by a voltage dividing circuit with a control value to feedback control the high-voltage output and outputs a voltage that is to be applied to a member involved in image formation. The high-voltage power supply includes a printed circuit board on which a resistor connected to a high-voltage output side of the voltage dividing circuit is mounted. A slit including a first portion and a second portion is formed in the printed circuit board. The first portion extends across a straight line connecting terminals of the resistor. The second portion continues from the first portion and extends in a direction receding from one of the terminals of the resistor.

Abstract: A charge roller conductive film and a developer cartridge. The conductive film has an input contacting an electrical contact of an image forming apparatus main assembly, an output electrically connecting with a charge roller and a transmission section connecting with the input and the output. The input has a middle contact plate shaped like a bent strip. A side contact plate is formed on at least one side of the middle contact plate.

Abstract: An image processing apparatus is provided that includes plural devices, a device control unit associated with each of the devices for controlling a power status of each of the devices according to a relevant power mode, and power mode setting unit for setting the relevant power mode to the device control unit.

Abstract: An image-forming apparatus includes an image carrier that has an electrically chargeable film formed on a surface thereof and that carries an image and a charging section that charges a surface of the film on the image carrier. The charging section includes a first charging member that applies a direct-current voltage between the first charging member and the image carrier and a second charging member that applies a direct-current voltage between the second charging member and the image carrier to charge the film on the image carrier to a predetermined surface potential after the first charging member charges the film on the image carrier. The voltage applied by the first charging member is decreased such that the surface potential of the image carrier after the voltage is applied by the first charging member is decreased as the film on the image carrier becomes thinner.

Abstract: A bias power supply device includes: a temperature detecting unit; a control signal generation unit generating and outputting an output frequency setting signal for setting a frequency of an alternating current power in accordance with a repetition frequency and a resonance frequency signal being set at a lower or higher repetition frequency according to the measured temperature; a waveform signal generation circuit generating a waveform signal for pulse-width modulation having a time constant for rising set by capacity and resistance based on the resonance frequency signal; a modulation circuit generating a pulse-width-modulated modulation signal based on the waveform signal and the output frequency setting signal; a switching circuit driven by the modulation signal; and a transformer having a first winding and a second winding, and supplying an alternating current power with a repetition frequency of the output frequency setting signal to an external load connected to the second winding.

Abstract: An image forming apparatus having; an electrostatic latent image support; a charger for charging the electrostatic latent image support; an exposure unit for exposing the electrostatic latent image support with a light beam to form an electrostatic latent image; a development unit for developing the electrostatic latent image into a toner image; a sheet feeding unit for feeding a recording sheet in an image forming operation; a transfer member for transferring the toner image to the recording sheet; a fuser for fusing the toner image onto the recording sheet; and a high-voltage power supply circuit for, in an image forming operation, applying a plurality of bias voltages at least to the charger and to the development unit, wherein the high-voltage power supply circuit supplies a high voltage only to the charger in an operation in an ion generation mode so as to cause the charger to generate ions.

Abstract: An image forming apparatus includes a photosensitive member, an exposure unit configured to expose the photosensitive member corresponding to an image, a developing unit configured to develop, using a toner, an electrostatic latent image formed on the exposed photosensitive member, a generation unit configured to generate a waveform signal for the developing unit, a parallel-to-serial conversion unit configured to apply, at a predetermined sampling period, parallel-to-serial conversion to a plurality of signals including the generated waveform signal, a serial-to-parallel conversion unit configured to apply, at the predetermined sampling period, serial-to-parallel conversion to the signals output from the parallel-to-serial conversion unit, and a voltage applying unit configured to apply to the developing unit a voltage composed of a direct-current voltage and an alternating-current voltage superimposed thereon based on the waveform signal among signals output from the serial-to-parallel conversion unit.

Abstract: The high-voltage output apparatus includes a voltage application part that applies a DC voltage to the charge member; a current detection part that detects a value of a current flowing in the image bearing member when the DC voltage is applied to the charge member; and a control part that calculates a plurality of discharge start voltages for the image bearing member, based on a plurality of current values detected by the current detection part as a result of the voltage application part applying a plurality of different DC voltages to the charge member, and controls the DC voltage applied to the charge member, using the plurality of calculated discharge start voltages. Consequently, a high-quality image can be formed by maintaining a potential on a photosensitive drum to be constant irrespective of the states of the circumstances and/or the drum layer thickness.

Abstract: An image forming apparatus including: one or a plurality of photosensitive drums; a plurality of chargers each having a grid, a voltage applying unit generating a charging voltage; a plurality of grid constant voltage circuits, each of the plurality of grid constant voltage circuits including: a voltage detecting unit that detects a voltage based on a grid voltage which is generated in the grid; a first current detecting unit detecting a first current; a voltage control line making the grid voltage constant; and an operation control device performing a feedback control such that the detected voltage has a predetermined voltage value; at least one of a second current detecting units detecting a second current flowing; and a controller controlling the voltage applying unit such that a sum of the first current and the second current corresponding to one of the plurality of chargers becomes a predetermined current value.

Abstract: An image formation device is provided with an image formation unit configured to form an image on a recording sheet, a first frame arranged to support the image formation unit, a second frame connected to the first frame, flexure rigidity of the second frame being smaller than flexure rigidity of the first frame, an electric substrate electrically connected with the image formation unit. With the above configuration, the electric substrate is arranged to extend from the first frame to the second frame and is secured onto the first frame with the position on the first frame being adjusted.

Abstract: A color multifunction printer as an example of an image forming apparatus includes a plurality of cartridges each containing a photoconductor; a support frame configured to support the cartridges arranged in tandem, the support frame being allowed to be pulled out horizontally from a casing of the apparatus to a position in which each of the cartridges is detachable from the support frame; and a plurality of exposure units mounted to the support frame, wherein each of the exposure units is disposed opposite to a corresponding photoconductor and is configured to expose the photoconductor to light to form an electrostatic latent image thereon. Each of the cartridges is configured to be detachable in such a direction that the photoconductor in the cartridge moves away from the corresponding exposure unit upon detachment.

Abstract: There is provided a power supply unit, comprising: a converter transformer; a first low voltage generation unit to generate a first voltage on a secondary side of the converter transformer and output the first voltage; a first controller that controls an activation state of a primary side of the converter transformer based on the first voltage; an inactivation unit to inactivate operation of the first controller based on the first voltage to let the first low voltage generation unit to suspend output of the first voltage; a high voltage supply unit to output a high voltage higher than the first voltage by using the first voltage; a detection unit to detect an anomalous state concerning output of the high voltage of the high voltage supply unit. The high voltage supply unit inactivates the operation of the first controller through the inactivation unit when the anomalous state is detected.

Abstract: An image forming apparatus that forms a color image by overlaying toner images formed on respective first, second, and third photoreceptors, comprising: first, second, and third voltage-applied members respectively facing the first, second, and third photoreceptors; a first AC power supply generating first AC voltage, and superimposing the first AC voltage on first DC voltage to generate first voltage for causing a first electric field between the first voltage-applied member and the first photoreceptor; a second AC power supply generating second AC voltage, and superimposing the second AC voltage on second DC voltage to generate second voltage for causing a second electric field between the second voltage-applied member and the second photoreceptor; and a composite circuit superimposing a composite of the first voltage and the second voltage on third DC voltage, to generate third voltage for causing a third electric field between the third voltage-applied member and the third photoreceptor.

Abstract: A PWM generating unit may include a base duty setting register configured to store a base duty value that is set thereto, and a PWM generator to obtain a corrected duty value by correcting the base duty value based on first correction data and second correction data, and to generate a PWM signal according to the corrected duty value. The first correction data may be computed from a rotation period of a first rotational body, and the second correction data may be computed from a rotation period of a second rotational body.

Abstract: An image forming apparatus having; image supporting members provided for a plurality of colors; chargers to be impressed with charging biases to charge the respective image supporting members; developing devices to be impressed with developing biases to develop latent images formed on the image supporting members; a charging bias power supply, including high-voltage DC power supply circuits and an AC power supply circuit, for applying the charging biases, which are generated by superposition of direct-current voltages and an alternate-current voltage, to the chargers; and a control circuit that performs stop processing to stop applications of the charging biases and the developing biases.

Abstract: A power feeding mechanism includes: a power-fed body placed in an apparatus main body, the power-fed body into which power is fed at least when the power-fed body is used; a placement portion where the power-fed body provided in the apparatus main body is placed; a power feed member provided in the apparatus main body and configured to move between a noncontact position and a contact position, the power feed member at the contact position that feeds power into the power-fed body from the apparatus main body; and a move unit that moves the power feed member to at least the two positions. At the noncontact position, the power feed member is noncontact in electric with the power-fed body being placed in the placement portion. At the contact position, the power feed member is contact in electric with the power-fed body being placed in the placement portion.

Abstract: A piezoelectric transformer includes a piezoelectric element. Two primary side electrodes exist on the primary side of the piezoelectric element. The primary side electrodes are coupled by a resistor formed from a conductive coating. A discharge current is discharged via the resistor to protect a semiconductor component from the discharge current. Since neither a short-circuit terminal nor conductive jig is required, electrostatic discharge damage to a semiconductor component can be prevented by a low-cost arrangement.