Abstract: An OPC 2, a charger 9, a cleaner 10 for cleaning the charger 9, a holder 11 for holding the charger 9, a support frame 12 for supporting the holder 11, a pair of springs 13 and 14 and a driver 15 for driving the holder are accommodated in a single process cartridge 8. The cleaner 10 can be brought into contact with the charger 9 and separated from the same. The driver 15 moves the cleaner 10 between a position of contact at which the cleaner 10 is brought into contact with the charger 9 and a position of separation at which the cleaner 10 is separated from the charger 9.

Abstract: The present invention provides an image forming apparatus, which has an image bearing body for bearing a toner image, transferring device for transferring a toner image on the image bearing body to a transferring material, a charging member for charging the image bearing body, having a residual toner after the transfer on a surface thereof by being brought into contact therewith, electrostatic image forming device for forming an electrostatic image on the image bearing body charged by the charging member, developing device for collecting the residual toner on the image bearing body while developing the electrostatic image on the image bearing body by using a toner charged in the same polarity as a charging polarity generated by the charging member, control device for controlling a voltage to be applied to the charging member, and a cleaning sequence for performing a cleaning of the charging member by applying a voltage not higher than a discharge threshold and equal to the polarity of the toner after a discha

Abstract: A charging device for electrophotography includes a charging brush, having many fibers extending in radial around a rotation shaft and contacted with a surface of a photosensitive drum, for rotating to electrically charge the surface of the photosensitive drum with the fibers, and a charging control member located on a downstream side of a contact between the charging brush and the photosensitive drum in a rotation direction of the charging brush for temporarily retarding a movement of the fibers of the charging brush to increase an effective density of the fibers to be contacted with the surface of the photosensitive drum. Particularly, an end of the charging control member is at a distance of at least 1 mm from the contact between the charging brush and the photosensitive drum.

Abstract: An image forming apparatus including a rotatable member configured to bear an image, a charging member configured to charge a surface of the rotatable member, and a cleaning member in sliding contact with a surface of the charging member. The surface of the cleaning member includes convex portions which engage with convex portions on a surface of the charging member so as to clean the surface of the charging member. Further, the surface of the charging member includes a surface roughness having a directivity set to a forward direction relative to a rotating direction of the rotatable member and set to a backward direction relative to the surface of the cleaning member.

Abstract: An automatic cleaning method for cleaning an electrifier of an image forming apparatus. A drive mechanism moves the cleaning member to clean the electrifier. An electrification time measuring section measures an electrification time of the electrifier after the last cleaning of the electrifier. A medium detecting section discriminates whether or not a medium is located in an image forming station. A control section controls the drive mechanism to render the cleaning member to clean the electrifier when a medium is not present in the image forming station after the measured electrification time reaches a determined time. The result is that automatic electrifier cleaning can be done at an appropriate preset timing, causing an elongated service life of the electrifier.

Abstract: An image forming apparatus includes an image bearing member; a charging member for charging a surface of the image bearing member while contacting thereto with a predetermined voltage applied to the charging member; exposure member for exposing the surface of the image bearing member to form an electrostatic latent image; a toner carrying member contacted to the image bearing member with a predetermined voltage applied to the toner carrying member to visualize the electrostatic latent image into a toner image with toner carried thereon; an image transfer member for urging a transfer material to contact the transfer material to the image bearing member with a predetermined voltage applied to the image transfer member to transfer the toner image onto the transfer material; a device for applying the predetermined voltages to the charging member, the toner carrying member and the transfer member; and a controller for controlling the device that applies the predetermined voltage, the controller being operable in a

Abstract: An electrophotographic image forming apparatus. The image forming, apparatus includes an organic photoconductive (OPC) drum for forming an image, a charging roller for applying a high voltage to the OPC drum, a developing roller for supplying toner to the OPC drum, a doctor blade for regulating of a toner layer to a predetermined thickness on the developing roller, a supply roller for supplying the toner to the developing roller, an agitator for supplying the, toner to the supply roller, a first cleaning blade formed on a portion of a predetermined frame at a side of the OPC drum, for scraping non-transferred roller on the OPC drum after a transferring operation, and a second cleaning blade formed on another portion of the frame above the first cleaning blade, at a side of the charging roller, for completely scraping non-transferred toner which avoids the cleaning operation of the first cleaning blade.

Abstract: An image forming apparatus includes an image bearing member, discharging wires for discharging electricity to the image bearing member, a frictionally sliding device for reciprocating while frictionally sliding along the discharging wires, and a switch for changing the numbers of reciprocation of the frictionally sliding devices. With the apparatus, it is made possible for the apparatus to perform discharges uniformly from the very beginning when the discharge wires are used, and also, to perform image formation without unevenness due to the stains that may adhere to the wires by the repeated use thereof.

Abstract: A charging device for an image forming apparatus includes a charging roller which contacts a surface of a photoconductive element under pressure and is caused to rotate by a rotation of the photoconductive element in which the charging roller charges the surface of the photoconductive element while rotating, and a cleaning member which contacts a surface of the charging roller, even when an image forming operation is performed, and cleans the surface of the charging roller. The cleaning member is made of an elastic material and is supported by a supporting member. The supporting member includes an elastic distortion suppressing member which suppresses a distortion of the cleaning member caused by the rotation of and made in a rotating direction of the charging roller.

Abstract: A method for cleaning an image-forming apparatus. Toner is charged to the first polarity prior to transferring the toner image to the print medium and accidentally inverted from the first polarity to a second polarity opposite to the first polarity during the transfer of the toner image to the print medium. When performing a cleaning operation, a first voltage of a first polarity is applied to at least one of a charging roller and a cleaning roller in contact with a surface of a photoconductor. The surface of the photoconductor is charged to a second voltage. The second voltage has a smaller value than the first voltage and is of the same polarity as the first voltage. Therefore, the toner of the second polarity sandwiched between the charged surface of the photoconductor and the at least one of the charging roller and cleaning roller is inverted in polarity, i.e., from the second polarity to the first polarity by triboelectric charging.

Abstract: Disclosed is a method for cleaning the contact charger of an electrophotographic apparatus including a photosensitive (photoconductive) drum, developing means, transfer means and main motor, which comprises the steps of applying a charging voltage of a specified level to the contact charger to make the surface of the photosensitive drum keep a surface potential of a given level during rotation of the main motor, cutting off the charging voltage applied to the contact charger and developing voltage applied to the developing means after a specified time so as to transfer the toner of opposite polarity attached to the contact charger to the photosensitive drum, and applying a negative transfer voltage to the transfer means so as to transfer the toner of opposite polarity transferred to the photosensitive drum to a sheet of paper.

Abstract: An image forming apparatus includes a movable image bearing member, a charging member capable of contacting with the image bearing member to charge the image bearing member, a cleaning member capable of contacting with the charging member to clean the surface of the charging member, a detecting circuit for detecting a parameter related to the deteriorated state of the surface of the image bearing member, and a controller for controlling the frequency of the cleaning member on the basis of the result of the detection by the detecting circuit.

Abstract: An image forming apparatus includes a rotatable image bearing member and a contact-charging member which contacts a surface of the image bearing member. The contact-charging member can charge the image bearing member by applying a predetermined voltage to the contact-charging member so that a potential of the contact-charging member is changed to a required potential for transferring a residual toner that is stuck on a surface of the contact-charging member facing the image bearing member onto the image bearing member while the image bearing member stops rotating. A method for removing residual toner sticking onto a contact-charging member that contacts a surface of the image bearing member changes a potential of the contact charging member to a required cleaning potential for transferring the residual toner sticking to a surface of the contact-charging member facing the image bearing member onto the contact-charging member while the image bearing member stops rotating.

Abstract: A charger for charging the surface of a photoconductive drum by a contact charging method in an electrophotographic image forming apparatus includes: a charge roller for charging an unexposed surface of the photoconductive drum to a prescribed potential by contact with the surface of the photoconductive drum; a power supply connected to the charge roller, for supplying a variable DC charge voltage to the charge roller; a potential sensor installed around the photoconductive drum, for detecting a charge potential value of the unexposed surface of the photoconductive drum; and a controller for comparing the charge potential value detected by the potential sensor with a specified value, and changing the charge voltage generated by the power supply upon detecting any difference therebetween, so as to maintain the charge potential of the photoconductive drum at a constant value.

Abstract: An electrostatic imaging device has a photoreceptor drum, an exposure unit to form a latent image on the photoreceptor, a developing unit for forming a toner pattern on the photoreceptor, a transcribing roller for electrifying the photoreceptor drum and transcribing the toner pattern onto a recording sheet, a brush charger for electrifying the photoreceptor drum, and a power supply section for applying a first negative voltage to the transcribing roller and a second negative voltage to the brush charger during a period other than an image forming period. The second voltage is lower than the first voltage in absolute value. Undesirable particles having a positive potential and attached to the brush charger is collected to the photoreceptor drum for cleaning the brush charger.

Abstract: An image forming apparatus of the present invention includes a charging device made up of a charge roller and a roller cleaning member for cleaning the charge roller. The charge roller is held in contact with a photoconductive element and uniformly charges the element while being driven by the element. The roller cleaning member is held in contact with the charge roller in order to remove impurities from the roller. The charge roller has a resistance ranging from 1.times.10.sup.3 .OMEGA. to 1.times.10.sup.7 .OMEGA.. The cleaning device exhibits a stable charging ability over a long time of use without resorting to a mechanism for moving the charge roller into and out of contact with the photoconductive element or for moving the roller cleaning member into and out of contact with the charge roller.

Abstract: A method of forming an electrostatic latent image includes printing operation and toner recovering operation. The printing operation includes charging, forming an electrostatic latent image, developing, and transferring operations. The toner recovering operation includes the step of charging the photosensitive drum in timed relation to the rotation of the photosensitive drum after printing operation so that reversely charged toner deposited on the charging roller migrates from the charging roller to the photosensitive drum. The toner migrated from the charging roller to the photosensitive drum is recovered into a developer. An apparatus for forming an image includes a charging roller, photosensitive drum, developing roller, and transfer roller.

Abstract: A cleaning assembly for polishing debris from a corona wire is disclosed. The cleaning assembly includes a seat movably mounted within a housing to slide along the length of the corona wire. The seat has a polishing element configured to deflect the corona wire from an operating position. The assembly further includes a handle protruding from the housing whereby as the handle is pulled away from the housing along a plane defined by the length of the corona wire, the polishing element deflects the corona wire and polishes the taut wire to clean the corona wire.

Abstract: A charging member is disposed so as to contact a surface of a charge-receiving member which moves relative to the charging member. In conjunction with the movement of the charge receiving member, the charging member removes foreign substance present on the charge-receiving member on the upstream side in the direction of travel of the charge-receiving member at the contact region with the charging member. Simultaneously, a discharge voltage is applied to the charging member so that the charging member charges the charge-receiving member in the area from which said foreign substance has been removed at the contact region on the downstream side of the charge-receiving member in the direction of travel of the charge-receiving member. During a cleaning operation, the charging member retracts from the charge-receiving member and is out of contact therewith in accordance with the number of image formations, black and white ratio, and humidity.

Abstract: A charge roller displacement mechanism prevents the build up of a sharply defined circumferential ring of contaminants on the surface of a charge roller in an electrophotographic printing system, thereby reducing the severity of the print defect caused by the contaminants. By cyclically laterally displacing the charge roller parallel to the longitudinal axis of a photoconductor drum as the photoconductor drum rotates, contaminants which reach the surface of the charge roller will not form a sharply defined circumferential ring that interferes with the uniform charging of a photoconductor drum charged by the charge roller. The charge roller displacement mechanism includes a first gear that engages the gear used to rotate paddles in a waste hopper of an electrophotographic printer cartridge. A second gear engages the first gear to provide a reduction of approximately 400 to 1.

Abstract: A method of controlling a charge voltage of an image forming apparatus using an electrophotographic developing process so as to enhance cleaning efficiency by increasing the number of collecting positively-charged toner adhering to contact charging unit. The method includes: applying a charge voltage of a predetermined voltage level to a contact charging unit to uniformly charge an outer surface of a photoconductive body to a predetermined polarity while a main motor rotates; when cleaning the contact charging unit, applying a charge voltage exhibiting a voltage level lower than the predetermined voltage level to the contact charging unit to create a potential difference between the contact charging unit the photoconductive body; and transferring charged toner particles adhered to the contact charging unit, to the photoconductive body by shutting off the charge voltage being applied to the contact charging unit.

Abstract: An image forming apparatus includes image bearing member for bearing a toner image; charging member contactable to the image bearing member to electrically charge the image bearing member; wherein .delta.V=.vertline.Vdc-Vs.vertline. is different between a first area of the image bearing member which is going to be image area and second area of the image bearing member which is going to be non-image area, where Vdc is a DC component of a voltage applied to the charging member, and Vs is is a potential of the image bearing member charged by the charging member.

Abstract: An integrated environmental management system for reproduction apparatus including a reprographic marking engine for reproducing information supplied thereto and accessories for facilitating the handling of reproduction output from the marking engine. The integrated environmental management system includes a housing associated with the reprographic marking engine. The housing defines a chamber having, in communication, a rear wall substantially parallel to the rear of the reprographic marking engine, first and second side walls, and top and bottom walls. An inlet plenum in the housing chamber communicates, for example, with an opening in the first side wall of the housing. The inlet plenum includes an inlet filter for preventing contaminants in ambient air from entering the inlet plenum, a first inlet duct directed into the general interior of the reprographic marking engine, and a plurality of inlet ducts directed respectively to specific systems within the reprographic marking engine.

Abstract: An image forming apparatus including a photoconductive drum, a charging roller which is held in pressured contact with the photoconductive drum, and a holder which holds a spreading blade having a free or unsupported end which is held in contact with the charging roller to spread toner and other particles which adhere to the surface of the charging roller. Preferably, there is a thin flexible film between the holder and the spreading blade. The spreading blade is held by the holder such that when the charging roller rotates, a frictional force pulls the spreading blade relative to the holder. This frictional force imposes a rotational moment on the spreading blade which reduces the force of the spreading blade against the charging roller when the charging roller rotates.

Abstract: A method of forming an electrostatic latent image includes printing operation and toner recovering operation. the printing operation includes charging, forming an electrostatic latent image, developing, and transferring operations. The toner recovering operation includes the step of charging the photosensitive drum in timed relation to the rotation of the photosensitive drum after printing operation so that reversely charged toner deposited on the charging roller migrates from the charging roller to the photosensitive drum. The toner migrated from the charging roller to the photosensitive drum is recovered into a developer. An apparatus for forming an image includes a charging roller, photosensitive drum, developing roller, and transfer roller.

Abstract: Non-magnetic toner in a fluidized bed is charged by at least one corona wire extending through the bed, the non-magnetic toner surrounding the wire in the fluidized bed. In order to prevent build up of insulating particles on the corona wire (which leads to a change in electric field gradient and eventually adversely impacts on the uniformity of the image applied to the substrate with the toner) is substantially precluded by vibrating the wire to shake toner particles off the wire. Vibration is accomplished at spaced points in time, such as by utilizing a rod having an irregular (e.g. substantially sinusoidal shaped) surface and by reciprocating the rod to cause the irregular surface to engage the wire and cause a quick rise and release thereof, so that the wire goes through a wide series of frequencies when vibrating. The rod may be reciprocated by a pneumatic cylinder, and may be of stainless steel having a substantially circular cross section with a diameter between about 0.02-0.04 inches.

Abstract: A method of controlling the charging operation of the contact charger of an electrophotographic apparatus including a photosensitive drum and a developing means for charging a toner with a negative voltage, the photosensitive drum and developing means being normally supplied with a negative voltage during printing, which includes the steps of: supplying a negative charging voltage of a specified level to the contact charger for a first interval defined as at least one initial rotation of the photosensitive drum in warm-up with the developing means not being supplied with a voltage, cutting off the negative charging voltage, and supplying a negative developing bias voltage which is lower than the surface voltage of the photosensitive drum to the developing means for a second interval defined as the interval before the stopping of the rotation of the photosensitive drum after the first period.

Abstract: An image forming apparatus includes a first image-bearing member, latent image-forming unit for forming an electrostatic latent image on the first image-bearing member, developer for developing the electrostatic latent image with a toner to form a toner image, an intermediate transfer member for receiving the toner image by primary transfer and transferring the toner image onto a second image-bearing member by secondary transfer, a charging member for charging a residual toner remaining on the intermediate transfer member after the secondary transfer, and a recovery member for recovering the charged residual toner at a recovery position by voltage application. The intermediate transfer member exhibits a charging characteristic such that it has a surface potential of at most 500 volts as an absolute value at the recovery position.

Abstract: An charging apparatus includes a housing having a charging side adapted to face a photoreceptor; and a sharp-edged electrode charging member provided in the housing so that the photoreceptor is charged through the charging side by corona discharge from the sharp-edged electrode charging member. The charging apparatus further comprises an air introducing member provided a rear side opposite to the charging side and for introducing air into the housing.

Abstract: An image forming apparatus having a device for moving a charging roller towards and away from a photoreceptor and a cleaning member for the charging roller. The charging roller moving device moves the charging roller to positions including a first position where the charging roller is in contact with the photoreceptor and is separated from the cleaning member for a charging operation, a second position where the charging roller is in contact with the cleaning member for cleaning the surface of the charging roller and a third position where the charging roller is separated from the photoreceptor and the cleaning member. Even if the apparatus is left unoperated for a long time, the photoreceptor is prevented from being contaminated by the charging roller by placing the charging roller in the third position.

Abstract: A cleaning device of a charging unit in an image forming apparatus using an electrophotographic process for cleaning a corona wire. The cleaning device comprises an elongated shield case having a guide slit in a central portion extending in a lengthwise direction of a photosensitive drum; a cleaning shaft guide containing a bore therein, mounted to the guide slit and adapted to slide along the guide slit, a cleaning shaft having a handle and an integrally connected body inserted into the bore and adapted to maintain a cleaning member at a distance from the corona wire during non-cleaning of the corona wire, and to allow, upon application of force, the cleaning member to resiliently press against the corona wire and move along the corona wire while being held in frictional contact with the corona wire during cleaning of the corona wire by way of an elastic spring disposed between the handle of the cleaning shaft and the cleaning shaft guide.

Abstract: An electrophotographic image forming apparatus using a charge roller for uniformly charging the surface of a photoconductive element, or image carrier, during image formation, and a charging device having the charge roller. The charging efficiency is enhanced, and a uniform charge distribution is set up by the application of a DC voltage only. This suppresses the increase in the cost of an apparatus, the increase in power source cost, and the generation of a great amount of ozone. As a result, a charging member and a photoconductive element are prevented from being deteriorated while environmental pollution is eliminated.

Abstract: Since the first cleaning member 24g scrapes off the foreign materials adhered to the corona charging electrode, and following that, the second cleaning member 24h wipes off the scraped foreign materials, the layered foreign materials firmly adhered on the corona charging electrode 22 is removed. Accordingly, image formation in electrophotographic apparatus or the like is suitably carried out, and image quality deterioration of the recorded image is suppressed.

Abstract: An image forming apparatus includes an image bearing member; a charging member for charging the image bearing member at a charging position, the charging member being contactable to the image bearing member; wherein the charging member is adapted to be supplied with a first DC voltage of a predetermined polarity for forming an image on the image bearing member and contains ion conduction material, and wherein the charging member is adapted to be supplied with a second voltage of a polarity opposite from the predetermined polarity when such an area of the image bearing member as is going to a non-image area of the image bearing member is at the charging position.

Abstract: At least a photosensitive drum 2 and charge roller 9 are attached to a unit 8 so that the photosensitive drum 2 and charge roller 9 can be freely attached to and detached from an apparatus body 1 in unison with the unit case 8, and the charge roller 9 can be freely brought into and out of contact with the surface of the photosensitive drum 2. The apparatus body 1 is provided with pressure cams 5a and 5b adapted to cause the charge roller 9 to be brought into and out of contact with the surface of the photosensitive drum 2.

Abstract: An image forming apparatus includes a rotating photosensitive body, a charging member which is rotated in a direction opposite to a rotational direction of the photosensitive body while contacting the photosensitive body in order to uniformly charge a surface of the photosensitive body, a cleaning member for cleaning a surface of the charging member, and a device for bringing the charging member into contact with the photosensitive body or separating the charging member from the photosensitive body. The charging member is rotated contacting the cleaning member in order to clean the charging member when the charging member is separated from the photosensitive body. A surface peripheral speed of the charging member made when the charging member is separated from the photosensitive body is reduced to become slower than a surface peripheral speed of the charging member maintained when the charging member is rotated contacting the photosensitive body.

Abstract: In the roller charging apparatus according to the present invention, the charging roller includes a layer of an epichlorohydrin rubber, so that it is possible to eliminate electric nonuniformity of a conductive elastic layer and to be charged by loading only a DC voltage. The charging roller also may have a surface layer formed of polyamide resin or fluorine resin. In addition durability can be improved by setting the roller hardness of the charging roller to 42 (measured by a JISA hardness meter) or more. Further, a roller diameter D.sub.r of the charging roller and drum diameter D.sub.d of the photosensitive drum may satisfy the relation of D.sub.d /D.sub.r .gtoreq.4. A cleaner can also be provided for removing foreign materials, such as toner, from the charging roller, and the cleaner may have a rubber hardness less than that of the charging roller.

Abstract: An image forming apparatus having an air flow structure capable of generating an airflow along a direction substantially perpendicular to a photosensitive drum through a charging device in order to prevent contamination of a corona wire (i.e., discharge wire). The image forming apparatus constructed according to the principles of the present invention includes a main frame having parallel side walls with a side wall having an air intake port. A cover is pivotally connected at one end of said main frame so as to allow closing and opening of the image forming apparatus and an image carrier is installed in the main frame so as to form a latent image. A ventilation fan installed at the port in the side wall generates an air flow through an air duct installed to guide the air flow.

Abstract: An image forming apparatus includes a contact charging member which contacts a surface of an image carrier member in order to charge the surface of the image carrier member, and a cleaning member which contacts and slides on a surface of the contact charging member in order to clean the surface of the contact charging member. The image forming apparatus performs a function in such a way that after an electrostatic latent image is produced on the image carrier member which is in a charged state, toner powder is supplied to the image carrier member by a developing device in order to make the electrostatic latent image visible and then a visualized image is transferred to a transfer member. In the image forming apparatus, a maximum height of concavities and convexities formed on the surface of the contact charging member is equal to or less than an average particle diameter of the toner powder supplied by the developing device.

Abstract: An apparatus and method for cleaning a corona wire in a toner supply and a toner cartridge employing the apparatus and method for cleaning a corona wire. The apparatus and method allow a user to free the corona wire from debris or excess toner without interrupting the use of a printer for long periods of time. The apparatus includes toner cartridge, a housing for the corona wire, and a compact cleaning cartridge tool. The cartridge cleaning tool further includes a cleaning support element, a cleaning element, a handle and a hook element.