| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 399089000 | Supplying power to charger | 20 |
| 20080304853 | Image forming apparatus - An aspect of the invention provides a charging control device of a color image forming apparatus, and the charging control device can properly control a charging potential of an image bearing body such that fog and uneven density are not generated even in a low-temperature environment. The image forming apparatus includes a high-voltage generation circuit | 12-11-2008 |
| 20090074443 | CHARGING DEVICE AND IMAGE FORMING APPARATUS USING THE SAME - A charging apparatus includes a charging member to charge a surface of a photoconductive medium, a power unit to supply an electric power as a bias voltage to the charging member, and a resistor unit to reduce a ripple on the surface of the charging member. Accordingly, a stability of the charging apparatus is secured without using a separate power device. | 03-19-2009 |
| 20090103940 | Image forming device - A tandem image forming device includes: a high voltage generating circuit for applying an oscillating voltage to a charging member disposed in contact with or proximity to an image carrier, the oscillating voltage having a DC voltage and an AC voltage superimposed thereon; a voltage control portion for controlling the peak-to-peak voltage of the AC voltage at a target voltage, the image forming device changing by switching a process speed depending on monochrome image formation and color image formation; a current detecting portion for detecting the value of a DC current between the image carrier and the charging member; and a frequency switching portion for switching the frequency of the AC voltage between frequencies according to the process speed. The voltage control portion includes an initial voltage adjusting portion for adjusting the target voltage on the basis of the value of the DC current detected by the current detecting portion. | 04-23-2009 |
| 20100092203 | CHARGING DEVICE FOR USING SCOROTRON CHARGING MECHANISM AND IMAGE FORMING DEVICE COMPRISING THE CHARGING DEVICE - A charging device is provided. The charging device includes a shield, a discharging part disposed inside the shield, a grid formed at an open end of the shield. The charging device further includes a power supply unit supplying charging power while maintaining the voltage difference between the discharging part and the grid at a predetermined level. | 04-15-2010 |
| 20110217064 | HIGH-VOLTAGE OUTPUT APPARATUS AND IMAGE FORMING APPARATUS - 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. | 09-08-2011 |
| 20110262173 | Image Formation Device - 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. | 10-27-2011 |
| 20110299872 | IMAGE FORMING APPARATUS HAVING A CHARGE MEMBER DISPOSED NEAR AN IMAGE BEARING MEMBER - Provided is an image forming apparatus having a charge brush for charging a transfer residual toner remaining on an intermediate transfer member. A toner is adhered to the charge brush. While a charge voltage is applied to the charge brush, the toner adhered to the charge brush is attracted by an electric field onto the charge brush. However, when the charge voltage is not applied to the charge brush, the toner adhered to the charge brush is moved to the intermediate transfer member. When a subsequent toner image is formed on the toner adhered to the intermediate transfer member, the quality of the subsequent image is deteriorated. Accordingly, the charge voltage is applied to the charge brush when an intermediate transfer area to which the toner image is transferred onto the intermediate transfer member immediately afterward faces the charge brush. | 12-08-2011 |
| 20120201561 | IMAGE FORMING APPARATUS - An image forming apparatus includes a photosensitive drum chargeable by a charging device; a developing device for developing an electrostatic image formed on the drum, wherein the developing device includes a carrying member for carrying and conveying toner to a position where the toner opposes the drum and a screw; a transfer device for transferring a toner image formed on the drum; an exposure device for lowering a potential of the drum by exposing the drum to light; and a controller for effecting, in a period in which the screw is rotated to supply the toner to a portion of the carrying member where the toner is not carried, such a control that the toner is not moved from the carrying member to the drum by electrically charging the drum and that an exposure amount of the drum is smaller than an exposure amount during image formation. | 08-09-2012 |
| 20120201562 | IMAGE FORMING APPARATUS THAT PREVENTS IMAGE DELETION - 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. | 08-09-2012 |
| 20120207506 | CHARGING DEVICE, IMAGE FORMING ASSEMBLY AND IMAGE FORMING APPARATUS USING THE CHARGING DEVICE - 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. | 08-16-2012 |
| 20120207507 | CONNECTOR, CHARGING DEVICE INCORPORATING SAME, AND IMAGE FORMING APPARATUS INCORPORATING THE CONNECTOR - A connector to electrically connect a rotary body having a shaft, the connector includes a connecting terminal, electrically connected to either a power supply or ground, to contact the shaft of the rotary body either at least two points or along a line; and a posture adjuster to hold the connecting terminal to adjust the posture of one of the connecting terminal and the rotary body to maintain contact between the connecting terminal and the shaft of the rotary body. | 08-16-2012 |
| 20120269534 | IMAGE FORMING APPARATUS - An image forming apparatus includes a image bearing member (drum); a developing device; a first charging member; a second charging member provided downstream of the first charging member and upstream of the developing device with respect to a rotational direction of the drum; a first power source for applying a DC voltage to the first charging member; a second power source for applying an oscillating voltage, in the form of a DC voltage biased with an AC voltage, to the second charging member; a detecting device for detecting a DC current passing through the second charging member; and a controller for controlling, when the oscillating voltage is applied to the second charging member while the DC voltage is applied to the first charging member, the DC voltage applied to the first charging member so that the detected DC current falls within a predetermined range including zero. | 10-25-2012 |
| 20130004196 | PRINTED CIRCUIT BOARD, POWER SUPPLY APPARATUS, IMAGE FORMING APPARATUS, AND PRINTED CIRCUIT BOARD MANUFACTURING METHOD - 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. | 01-03-2013 |
| 20130077985 | IMAGE FORMING APPARATUS - 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. The control circuit performs processing to attenuate each of the direct-current voltages and each of the developing biases, and after all the direct-current voltages have become a predetermined stop potential, the control circuit performs processing to stop the outputs of the direct-current voltages and the alternate-current voltage. | 03-28-2013 |
| 20130183057 | IMAGE FORMING APPARATUS AND POWER CONTROL DEVICE - 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. | 07-18-2013 |
| 20140294424 | SEMI-CONTACT BIAS CHARGE ROLLER - 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 | 10-02-2014 |
| 20150093137 | HIGH-VOLTAGE POWER SOURCE, CHARGING DEVICE INCORPORATING SAME, AND HIGH-VOLTAGE POWER SUPPLYING METHOD - 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. | 04-02-2015 |
| 20160070194 | IMAGE FORMING APPARATUS - The present invention relates to an image forming apparatus that forms an image by consecutively superposing toner images that have been formed on a plurality of photosensitive drums, on an intermediate transfer member or a transfer medium. The image forming apparatus is made compact and operates at a low cost. Since a current supply member supplies a current in a rotational direction of an intermediate transfer belt, multiple first transfer portions do not need corresponding voltage sources. Even in the case where a charging member supplies a current, the potential of the intermediate transfer belt is maintained at a predetermined potential by a constant-voltage element connected to support rollers. | 03-10-2016 |
| 20160187802 | IMAGE FORMING APPARATUS - An image forming apparatus comprises a plurality of image forming units that respectively form an image, and a plurality of voltage generation circuits that respectively generate voltages for driving the plurality of image forming units. Each of the plurality of voltage generation circuits comprises a voltage generation circuit having a transformer, and generates a voltage by a switching operation that is driven by changing an input voltage of primary side of the transformer, an oscillation circuit that generates a clock signal of a frequency that becomes a reference frequency of the switching operation and a setting unit that sets the frequency of the clock signal that the oscillation circuit generates. The setting units of the plurality of voltage generation circuits set the frequencies of the respective clock signals. | 06-30-2016 |
| 20160378014 | POWER SUPPLY STRUCTURE, CHARGING DEVICE, ASSEMBLY, AND IMAGE FORMING APPARATUS - A power supply structure includes a bearing, a first spring, and a second spring. The bearing supports a rotary member that axially rotates while contacting with a contact target. While receiving power, the first spring contacts with and presses the bearing with an end portion of the first spring to bring the rotary member into contact with the contact target. The second spring extends from the first spring toward the contact target and contacts with the rotary member. | 12-29-2016 |
