Patent application number | Description | Published |
20080298832 | DEVELOPER COLLECTING/CHARGING DEVICE, IMAGE FORMING APPARATUS AND CLEANING METHOD - After-transfer remaining toner is reversely transferred from a transfer member to an image carrier. A toner collecting/charging device for temporarily collecting and charging the after-transfer remaining toner remaining on the transfer member includes a toner collecting/charging roller which is provided in such proximity to the transfer member as not to make contact with a primarily transferred toner image, and which has a collecting function of temporarily collecting the after-transfer remaining toner and a charging function of charging the after-transfer remaining toner to a specified polarity, power supplies which are so connected that a voltage in which an AC voltage is superimposed on a DC voltage is applied to the roller, and a selector switch for changing a waveform of the AC voltage so that the toner collecting/charging roller is switched between a toner-collecting mode and a toner-releasing mode. | 12-04-2008 |
20090214276 | CLEANING DEVICE AND IMAGE FORMING DEVICE - A cleaning device for cleaning residual toner that, in an image forming device of an intermediate transfer type, remains on an outer circumferential surface of an intermediate transfer member after a transfer. The cleaning device includes: a charging brush operable to contact with and charge the residual toner; and a cleaner that is disposed downstream of the charging brush in a toner transport direction of the intermediate transfer member, and is operable to electrostatically adsorb the charged residual toner, wherein electrically conductive bristles have been planted randomly in the charging brush to be distributed evenly in density. | 08-27-2009 |
20090311002 | CLEANING DEVICE AND IMAGE FORMING APPARATUS INCORPORATING SAME - A first roll brush is formed from material having the positive triboelectric charge polarity against toner. A positive bias is applied to the first roll brush through a first collection roller by a first bias application device. A second roll brush is formed from material having the negative triboelectric charge polarity against toner. A negative bias is applied to the second roll brush through a second collection roller by a second bias application device. Thus, the first and second roll brushes are applied by each of biases having polarity identical to the triboelectric charge polarity of material of the roll brush against toner. This enhances cleaning performance of both the roll brushes and prevents degradation of the cleaning performance. | 12-17-2009 |
20090317123 | IMAGE FORMING APPARATUS - When a number of print pages, a driving time or a toner adhering amount exceeds a cleaning trigger value during no transfer operation, a circumferential speed of a secondary transfer roller is changed with respect to a circumferential speed of an intermediate transfer belt so as to clean the secondary transfer roller. Particularly, a surface of the secondary transfer roller is totally cleaned when the circumferential speed of the secondary transfer roller is made relatively faster and then slower or vice versa than the circumferential speed of the intermediate transfer belt because the surface of the secondary transfer roller is elastically deformed in both upstream and downstream directions so that the residual toner on the uneven foam surface of the secondary transfer roller is extruded. | 12-24-2009 |
20100098460 | FIXING DEVICE AND IMAGE FORMATION APPARATUS THAT EFFICIENTLY REMOVES RESIDUAL TONER ON INTERMEDIATE TRANSFER BELT - Disclosed is an image formation apparatus for forming an image by transferring, onto a recording sheet, a toner image that has been transferred from an image carrier onto an intermediate transfer belt | 04-22-2010 |
20100232824 | IMAGE FORMING APPARATUS - An image forming apparatus comprises: a rotatable image carrier operable to carry a toner image on a surface thereof; a transfer part operable to electrostatically transfer the toner image carried on the surface of the image carrier, onto a transfer material; a cleaning member that is in contact with the surface of the image carrier and that is operable to clean toner remaining on the surface of the image carrier after transfer by the transfer part; and a voltage supplier operable to apply, to the cleaning member, a bias voltage that is for cleaning the surface of the image carrier and that has a polarity opposite to a normal charging polarity of the toner. Here, application of the bias voltage by the voltage supplier starts before rotation of the image carrier starts, and when Vr>0, 009-16-2010 | |
20110229176 | IMAGE FORMING APPARATUS - An image forming apparatus has an image carrier that carries a toner image; a transfer member that is opposed to the image carrier, a transfer voltage being applied to the transfer member so that the toner image is transferred from the image carrier to a print medium passing between the transfer member and the image carrier; a first voltage application device that applies the transfer voltage to the transfer member; a separation member to which a separation voltage is applied so that the print medium is separated from the image carrier; a second voltage application device that applies the separation voltage to the separation member; a sensing device that senses an image density of the toner image; and a control section that controls a magnitude of the separation voltage based upon the image density of the toner image. | 09-22-2011 |
20110229185 | IMAGE FORMING APPARATUS - An image forming apparatus having an image carrier that carries a toner image; an opposed member that is provided so as to be opposed to the image carrier; an application device that applies a bias to the opposed member; and a control device that controls the application device to apply a first bias and thereafter a second bias to the opposed member so as to remove toner from the opposed member. The first bias has an absolute value that is large enough to cause discharge from the opposed member into air. The second bias has an absolute value that is too small to cause discharge from the opposed member into the air, and has a reverse polarity to the first bias. | 09-22-2011 |
20120008967 | IMAGE FORMING APPARATUS AND METHOD FOR STOPPING DRIVING IMAGE CARRIER - An image forming apparatus comprising: an image carrier to carry a toner image; a driving unit to drive the image carrier to rotate; a transfer unit to transfer the toner image at a transfer position; a cleaner at a cleaning position to remove toner remaining on the image carrier after transfer; an obtaining unit to obtain information indicating a likelihood of the remaining toner adhering to the image carrier; a judging unit to judge whether or not the likelihood is equal to or lower than a predetermined value; and a controller to control the driving unit (i) to stop driving the image carrier before a rear end of an area of the image carrier on which the toner remains reaches the cleaning position, when the judging unit judges affirmatively, and, (ii) to stop driving the image carrier after the cleaner removes the remaining toner, when the judging unit judges negatively. | 01-12-2012 |
20120195617 | IMAGE FORMING APPARATUS - An image forming apparatus is for transferring a toner image on an image carrier onto a transfer medium, and thermally fixing the toner image by a fixing device, and comprises a cleaner removing residual toner on the image carrier. The apparatus: acquires information relating to a distribution of a density of the residual toner at each position within a section on the image carrier at an end of an image forming job, the section extending from the transfer position to immediately before a cleaning position; determines, based on the information, whether or not the density of the residual toner at the transfer position exceeds a corresponding threshold density pertaining to occurrence of fusion of the residual toner; and causes, if determining negatively, the drive unit to stop when the image forming job is completed and the residual toner at the transfer position reaches a predetermined position within the section. | 08-02-2012 |
20120308251 | IMAGE FORMING APPARATUS - An image forming apparatus having: a toner image carrier; a transfer member; a transfer voltage applying device which applies a bias voltage to the transfer member; a voltage controller which performs constant voltage control on the transfer voltage applying device; a transfer contribution current detecting device; an antistatic member for removing static electricity from the record medium after transfer of a toner image; and an antistatic voltage applying device which applies an AC voltage to the antistatic member. The transfer contribution current detecting device measures current values during a current detection time, which corresponds to an integral multiple of a period of the AC voltage applied to the antistatic member, and detects a transfer contribution current value from the measured values, and the voltage controller controls the bias voltage applied to the transfer member based on the transfer contribution current value. | 12-06-2012 |
20130195528 | IMAGE FORMING APPARAUS - Brush rollers rotate in a direction indicated by an arrow while being in contact with an image formation surface to remove toner remaining on the image formation surface from an intermediate transfer belt. The brush rollers each mainly include a rotational shaft and a brush. The brush rollers face the intermediate transfer belt with brush winding directions being opposite from one another. The brush rollers rotate in the direction indicated by the arrow. Thus, seams of the brush rollers can be prevented from being in contact with the same portion on the image formation surface of the intermediate transfer belt. | 08-01-2013 |
20130294792 | IMAGE FORMING APPARATUS - An image forming apparatus having: an image support that supports a toner image; a transfer member adapted to sandwich with the transfer member and the image support; a voltage application unit that applies a transfer bias voltage to the transfer member; a current detecting unit that detects transfer current flowing from the voltage application unit to the transfer material after transfer processing on the transfer material starts; and a control unit that sets an upper limit of transfer current on the basis of a value of the transfer current detected by the current detecting unit, and thereafter further acquires a transfer current value from the current detecting unit to control a transfer bias voltage generated by the voltage application unit, such that the transfer current value during transfer does not exceed the upper limit. | 11-07-2013 |
20140376950 | IMAGE FORMING APPARATUS - An image forming apparatus includes an image carrier configured to carry a toner image. A transfer unit is configured to transfer the toner image on the image carrier onto a recording sheet. A fixing unit is configured to fix the toner image transferred at the transfer unit onto the recording sheet. Through a conveyance path, the recording sheet is conveyed from the transfer unit to the fixing unit. A conveyance guide member is disposed in the conveyance path on an image formation surface side of the recording sheet. A fan is configured to send air from the transfer unit to the conveyance path toward a gap defined between the conveyance guide member and the transfer unit so as to form a flow of air in the conveyance path from an upstream side to a downstream side in a conveyance direction of the recording sheet. | 12-25-2014 |
20160077470 | Image Forming Apparatus - An image forming apparatus has an image carrier that carries a toner image; a transfer member that is opposed to the image carrier, a transfer voltage being applied to the transfer member so that the toner image is transferred from the image carrier to a print medium passing between the transfer member and the image carrier; a first voltage application device that applies the transfer voltage to the transfer member; a separation member to which a separation voltage is applied so that the print medium is separated from the image carrier; a second voltage application device that applies the separation voltage to the separation member; a sensing device that senses an image density of the toner image; and a control section that controls a magnitude of the separation voltage based upon the image density of the toner image. | 03-17-2016 |