JP2014178558A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of maintaining a cleaning performance of a cleaning brush (a first cleaning member) which cleans the surfaces of a photoreceptor (a latent image carrier) and a charging roller (a charging member) and thereby allows for printing of a stable high-quality image.SOLUTION: An image forming apparatus is provided with a first power supply (first bias supply means) for supplying a bias to a charging roller 4 which uniformly charges a surface of a photoreceptor 3, and a second power supply (second bias supply means) for supplying a bias to a cleaning brush 8. A sub cleaning member A (a second cleaning member) adjacent to the cleaning brush 8 is arranged. At the timing when the cleaning capability of the cleaning brush 8 is saturated, the sub cleaning member A is moved to contact with the cleaning brush 8 to clean the cleaning brush 8.

Description

  The present invention relates to an image forming apparatus such as a printer, a copying machine, and a facsimile, and more specifically, adheres to the surface of an image carrier after a toner image is transferred to a transfer member and the surface of a charging member that charges the image carrier. The present invention relates to an image forming apparatus that collects a transfer residual toner by a cleaning member.

  Cleaning of an image forming apparatus that collects, by a cleaning member, transfer residual toner adhering to the surface of the image carrier after the toner image is transferred to the transfer body and the surface of the charging member that charges the image carrier in the image forming apparatus. There has already been proposed a technique for performing cleaning by applying a bias to the cleaning brush when the surface of the photosensitive member is cleaned with a brush or the like.

  However, since the toner adheres to the cleaning brush and the cleaning performance deteriorates, it is necessary to clean the cleaning brush. For this reason, an apparatus for applying a bias to the cleaning brush has been proposed, but the cost is increased and the apparatus becomes complicated. In addition, since the image carrier and the cleaning brush are always in contact, there is room for improvement in terms of durability.

  Japanese Unexamined Patent Application Publication No. 2004-109394 (Patent Document 1) discloses a technique for the purpose of improving the cleaning performance of the charging member and extending the life of the charging member. In Patent Document 1, the charging roller is cleaned when the cumulative number of prints is larger than the print number threshold value and the cumulative drum cycle number is larger than the drum cycle number threshold value, and when the cumulative formed pixel number is larger than the formed pixel number threshold value. The structure to perform is disclosed.

  However, since the thing of patent document 1 is not the structure which mounts the cleaning brush, from the viewpoint of a cleaner system, the problem that it gets dirty and the image is affected while cleaning brushes endurance cannot be solved.

  It is an object of the present invention to maintain a cleaning performance of a cleaning member in an image forming apparatus and enable stable high-quality image printing.

  2. An image forming apparatus according to claim 1, comprising: a latent image carrier that carries a latent image on its endlessly moving surface; a developing unit that develops the latent image on the latent image carrier with toner; and the latent image carrier. A charging member that uniformly charges the surface of the latent image carrier while moving its own surface in contact with the first end; a first bias supply unit that supplies a bias to the charging member; and Toner adhering to the surface of the latent image carrier and the charging member while endlessly moving its surface in contact with the latent image carrier and the charging member on the upstream side in the rotation direction of the latent image carrier In the image forming apparatus comprising: a cleaning member that recovers the surface of the latent image carrier and the charging member; and a second bias supply unit that supplies a bias to the cleaning member. The cleaning unit for cleaning the surfaces of the carrier and the charging member Is a first cleaning member, a second cleaning member is disposed in proximity to the first cleaning member, and the second cleaning member is moved at a timing when the cleaning capability of the first cleaning member is saturated. The first cleaning member is cleaned by contacting with the first cleaning member.

  According to the image forming apparatus of the first aspect, the cleaning performance of the first cleaning member can be maintained by the second cleaning member, and a stable high-quality image can be printed.

1 is a schematic configuration diagram illustrating a main part of a printer as an image forming apparatus to which the present invention is applied. FIG. 2 is a schematic configuration diagram of a process unit during a non-print job in the image forming apparatus according to the embodiment. It is a figure which shows the 1st Example of the subcleaning member in embodiment. It is a figure which shows the 2nd Example of the sub-cleaning member in embodiment. It is a figure which shows the 3rd Example of the sub-cleaning member in embodiment. It is a figure which shows the 4th Example of the sub-cleaning member in embodiment.

  Hereinafter, as an image forming apparatus to which the present invention is applied, an embodiment of an electrophotographic color laser printer (hereinafter simply referred to as a printer) will be described. First, a basic configuration of the printer according to the present embodiment will be described. FIG. 1 is a schematic configuration diagram illustrating a main part of the printer according to the present embodiment. This printer includes four process units 1Y, 1M, 1C, and 1K for forming toner images of respective colors of yellow, magenta, cyan, and black (hereinafter referred to as Y, M, C, and K). An optical writing unit 50, a registration roller pair 54, a transfer unit 60, and the like are also provided. Subscripts Y, M, C, and K added to the end of each symbol indicate members for yellow, magenta, cyan, and black, respectively.

  The optical writing unit 50 includes a light source composed of four laser diodes corresponding to each color of Y, M, C, and K, a regular hexahedral polygon mirror, a polygon motor for rotationally driving the polygon mirror, an fθ lens, a lens, and a reflection mirror. Etc. The laser light L emitted from the laser diode reaches any one of four photoconductors 3 described later while being reflected by any one surface of the polygon mirror and deflected as the polygon mirror rotates. . The surfaces of the four photosensitive members 3 are optically scanned by the laser beams L respectively emitted from the four laser diodes.

  The process units 1Y, 1M, 1C, and 1K have the same configuration, and the drum-shaped photoconductor 3 as a “latent image carrier” and development as “developing means” individually corresponding to the photoconductor 3 Each has a device 40 and the like. The photosensitive member 3 is made of a base tube made of aluminum or the like and covered with an organic photosensitive layer, and is driven to rotate in the clockwise direction in the drawing at a predetermined linear velocity by a driving unit (not shown). Then, it is optically scanned in the dark by an optical writing unit 50 that emits a laser beam L modulated based on image information sent from a personal computer (not shown) or the like, and static for Y, M, C, and K. Carries an electrostatic latent image.

  As shown in FIG. 2, the process units 1Y, 1M, 1C, and 1K include a photosensitive member 3, a charging roller 4 as a “charging member”, a cleaning brush 8 as a “first cleaning member”, and a “second cleaning”. A sub-cleaning member A as a “member” is provided. Further, these members, a static elimination lamp (not shown), a developing device 40 as developing means, and the like are held as a single unit in a common unit casing (holding body) so that they can be attached to and detached from the printer main body.

  The photosensitive member 3 that is a member to be charged and a latent image carrier has a diameter in which a photosensitive layer made of a negatively charged organic photophotoconductive substance (OPC) is coated on the surface of a conductive substrate made of an aluminum base tube. The drum is about 24 mm. The photosensitive member 3 is driven to rotate in the clockwise direction in the drawing at a predetermined linear velocity by a driving means (not shown).

  The charging roller 4 has a metal shaft that is rotatably received by a bearing (not shown), and the roller surface is rotated around the shaft by a driving means (not shown) in the clockwise direction in FIG. 3 is rubbed. As shown in FIG. 2, the shaft of the charging roller 4 is connected to a first power supply device 70 as a “first bias supply means” composed of a power supply, wiring, etc. provided in the apparatus main body. A charging bias consisting of a DC voltage is applied. In this printer, a charging system for uniformly charging the peripheral surface of the photosensitive member 3 is constituted by the charging roller 4, a driving means (not shown) for rotating the charging roller 4, and the above-described charging bias supply device. Then, a discharge is generated between the charging roller 4 and the photosensitive member 3 to uniformly charge the surface of the photosensitive member 3 to, for example, a negative polarity. In the charging system, the charging roller 4 is disposed in each of the process units 1Y, 1M, 1C, and 1K and is attached to and detached from the printer main body together with the photosensitive member 3 and the like.

  An electrostatic latent image is formed on the surface of the uniformly charged photoreceptor 3 by optical scanning by the optical writing unit 50 described above, and this electrostatic latent image is developed into a toner image by the developing device 40.

The developing device 40 includes a developing roller 42 that is disposed so as to contact and face the photoreceptor 3 and exposes a part of its peripheral surface from an opening provided in the casing 41. The developing roller 42 is driven to rotate by a driving unit (not shown). The casing 41 contains a developer (not shown) whose main component is a negative polarity toner corresponding to each color. In the present embodiment, a pulverized toner having a particle size of 8.5 [μm] is used as a developer, and HMDS-treated silica having a specific surface area of 200 [m ² / g] is used as an external addition treatment. % And 2% of HMDS-treated silica with a specific surface area of 90 [m ² / g]. The developer is pumped up on the surface of the developing roller, and when the developer roller passes through a position facing a developing doctor (not shown) as the developing roller rotates, the thickness of the developer is regulated, and then the developer comes into contact with the developing region facing the photoreceptor 3. The electrostatic latent image on the photoreceptor 3 is developed into a toner image.

  The Y toner image on the photoreceptor 3 is intermediately transferred onto the intermediate transfer belt 61 at a primary transfer nip where the photoreceptor 3 and the intermediate transfer belt 61 are in contact with each other. Untransferred toner that has not been transferred onto the intermediate transfer belt 61 adheres to the surface of the photoreceptor 3 after passing through the primary transfer nip. The transfer residual toner is removed from the surface of the photosensitive member 3 by the cleaning brush 8 that is in contact with the charging roller 4 and the photosensitive member 3 on the upstream side of the charging roller 4 in the rotation direction of the photosensitive member 3. Further, a small amount of untransferred toner that could not be removed from the photoconductor 3 by the cleaning brush 8 adheres to the surface of the charging roller 4 that is in contact with the photoconductor 3. Is also removed by the cleaning brush 8. A bias is applied to the cleaning brush 8Y by a second power supply device 71 as "second bias supply means" provided in the apparatus main body.

  Each of the plurality of flocked fibers of the cleaning brush 8 is obtained by cutting conductive fibers into a predetermined length and imparting conductivity by dispersing conductive particles such as carbon and metal fine powder in a resin material. . Considering the manufacturing cost and low Young's modulus, conductive fibers in which carbon is dispersed in nylon resin are preferable. Carbon dispersion may be unevenly distributed in the fiber.

  In FIG. 1, a transfer unit 60 is disposed below the process units 1Y, 1M, 1C, and 1K for the respective colors. The transfer unit 60 moves the endless intermediate transfer belt 61 endlessly in the counterclockwise direction in the drawing while being stretched by a plurality of stretching rollers. Specifically, the plurality of stretching rollers are a driven roller 62, a driving roller 63, four primary transfer bias rollers 66, and the like.

  The driven roller 62, the primary transfer bias roller 66, and the drive roller 63 are all in contact with the back surface (loop inner peripheral surface) of the intermediate transfer belt 61. Each primary transfer bias roller 66 is a roller in which a metal core is covered with an elastic body such as a sponge, and is pressed toward the photoreceptor 3 corresponding to each color of Y, M, C, and K. Thus, the intermediate transfer belt 61 is sandwiched. As a result, primary transfer nips corresponding to the respective colors Y, M, C, and K in which the respective photoreceptors 3 and the intermediate transfer belt 61 are in contact with each other with a predetermined length in the belt moving direction are formed as the primary transfer portion 69. Has been.

  A primary transfer bias that is constant-current controlled by a transfer bias power source (not shown) is applied to the core metal of each primary transfer bias roller 66. As a result, a transfer charge is applied to the back surface of the intermediate transfer belt 61 via each primary transfer bias roller 66, and a transfer electric field is formed between the intermediate transfer belt 61 and the photoreceptor 3 at each primary transfer nip. . In this printer, the primary transfer bias roller 66 is provided as the primary transfer unit, but a brush, a blade, or the like may be used instead of the roller. A transfer charger or the like may be used.

  The Y, M, C, and K toner images formed on the photoconductors 3 for the respective colors are transferred onto the intermediate transfer belt 61 in an overlapping manner at the primary transfer nip for each color. As a result, a four-color superimposed toner image (hereinafter referred to as a four-color toner image) is formed on the intermediate transfer belt 61.

  A secondary transfer bias roller 67 is in contact with the driving roller 63 on the intermediate transfer belt 61 from the belt front surface side, thereby forming a secondary transfer nip. A secondary transfer bias is applied to the secondary transfer bias roller 67 by a voltage applying means including a power source and wiring (not shown). As a result, a secondary transfer electric field is formed between the secondary transfer bias roller 67 and the grounded secondary transfer nip back roller 64. The four-color toner image formed on the intermediate transfer belt 61 enters the secondary transfer nip as the belt moves endlessly.

  The printer includes a paper feed cassette (not shown), and accommodates a recording paper bundle in which a plurality of recording papers P are stacked therein. Then, the uppermost recording paper P is sent out to the paper feed path at a predetermined timing. The fed recording paper P is sandwiched in a registration nip of a registration roller pair 54 disposed at the end of the paper feed path.

  The registration roller pair 54 rotates both rollers in order to sandwich the recording paper P sent from the paper feed cassette into the registration nip. However, as soon as the leading edge of the recording paper P is sandwiched, both rollers rotate. Stop. Then, the recording paper P is fed toward the secondary transfer nip at a timing at which the recording paper P can be synchronized with the four-color toner image on the intermediate transfer belt 61. At the secondary transfer nip, the four-color toner images on the intermediate transfer belt 61 are collectively transferred onto the recording paper P by the action of the secondary transfer electric field and the nip pressure, and become a full-color image combined with the white color of the recording paper P. .

  The recording paper P on which the full-color image is formed in this manner is discharged from the secondary transfer nip, and then sent to a fixing device (not shown) to fix the full-color image. The secondary transfer residual toner adhering to the surface of the intermediate transfer belt 61 after passing through the secondary transfer nip is removed from the belt surface by the belt cleaning device 68.

  Next, features of the printer according to the embodiment will be described. Unless otherwise specified, the basic configuration of the printer according to each embodiment is the same as that described above.

  The printer according to this embodiment employs a so-called cleaner-less method as shown in FIG. This cleaner-less method executes an image forming process on the latent image carrier without using a dedicated means for cleaning and collecting the transfer residual toner adhering on the latent image carrier such as the photosensitive member 3. It is a method to do. Specifically, the dedicated means for cleaning and collecting means that after the transfer residual toner is separated from the latent image carrier, it is transported to the waste toner container and collected without being attached to the latent image carrier again. Or transported into the developing device 40 for recycling. A cleaning blade that scrapes off the transfer residual toner from the latent image carrier is also included in the dedicated means.

  This cleaner-less method will be described in detail. The cleaner-less method is roughly classified into a scattering passing type, a temporary trapping type, and a combined type. Of these, in the scattering passing type, the transfer residual toner on the photosensitive member 3 is scratched by using a scattering member such as a cleaning member such as a brush that rubs against the photosensitive member 3. To weaken the adhesive strength. Thereafter, the transfer residual toner on the photosensitive member 3 is electrostatically transferred to the developing member such as the developing roller 42 immediately before or in the developing region where the developing member such as the developing sleeve and the developing roller 42 and the photosensitive member 3 face each other. By doing so, it collects in the developing device 40.

  Prior to this collection, the transfer residual toner passes through the optical writing position for writing the latent image. However, if the amount of transfer residual toner is relatively small, the latent image writing is not adversely affected. . However, if a reversely charged toner charged to a polarity opposite to the normal polarity is included in the transfer residual toner, it is not collected on the developing member, which causes background contamination. In order to suppress the occurrence of background contamination due to the reversely charged toner, the toner charging means for charging the transfer residual toner on the photoreceptor 3 to the normal polarity is provided between the transfer position and the scattering position by the scattering member, or the scattering position. It is desirable to provide it between the developing area and the developing area. As the scattering member, a fixed brush having a plurality of flocked fibers made of conductive fibers, a brush roller in which a plurality of flocked fibers are erected on a metal rotating shaft member, a roller having a roller portion made of a conductive sponge, etc. A member etc. can be used.

  In the temporary capture type in the cleanerless system, the transfer residual toner on the latent image carrier is temporarily captured by a capture member such as a rotating brush member that moves endlessly while the surface is in contact with the latent image carrier. Then, after the end of the print job or at the timing between sheets of the print job, the transfer residual toner on the capturing member is discharged and retransferred to the latent image carrier, and then electrostatically transferred to the developing member such as the developing roller. And collected in the developing device 40. In the above-mentioned scattering passing type, there is a risk that image deterioration will occur beyond the recovery ability to the developing member when the residual toner after transfer such as when a solid image is formed or after a jam occurs. On the other hand, in the temporary capture type, the transfer residual toner captured by the capture member can be collected little by little on the developing member, and the occurrence of such image deterioration can be suppressed.

  In the combined type in the cleaner-less method, the scattered passing type and the temporary capturing type are used in combination. Specifically, a rotating brush member that contacts the latent image carrier is used in combination as a scattering member and a capturing member. By applying only a DC voltage to the rotating brush member, etc., the rotating brush member is made to function as a scattering member, while the bias is switched from DC voltage to AC / DC / AC voltage as necessary to capture the rotating brush member, etc. It functions as a member.

  In the process units 1Y, 1M, 1C, and 1K of the present embodiment, a temporary capture type cleanerless system is adopted. In a print job in which a latent image is written by the optical writing unit 50, in order to prevent charging failure of the photoconductor 3, the transfer residual toner adhering to the photoconductor 3 and the charging roller 4 is cleaned. The transfer residual toner collecting mode captured by the brush 8 is executed. That is, the cleaning brush 8 is cleaned at the end of the print job or at the sheet interval. For this reason, a transfer residual toner discharge mode is executed in which the transfer residual toner captured by the cleaning brush 8 is transferred to a non-image area on the photosensitive member 3 directly and via the charging roller 4 as indicated by an arrow in FIG. For example, the cleaning brush 8 is cleaned in the toner discharge mode from the time the power is turned on to before the start of the print job, between the previous image and the next image, and from the end of the print job to the start of the next print job. During the print job, the photosensitive member 3 and the charging roller 4 are cleaned in the toner recovery mode.

  As described above, the photosensitive brush 3 and the charging roller 4 are cleaned by the cleaning brush 8 as the first cleaning member. As the cleaning of the photosensitive drum 3 and the charging roller 4 proceeds, the cleaning brush 8 is cleaned. The toner may adhere to the brush 8 and the cleaning performance may deteriorate. As a result, there is a problem that the image is affected. Therefore, a sub-cleaning member A as a second cleaning member is disposed in the vicinity of the cleaning brush 8 (first cleaning member). Then, at a timing when the cleaning ability of the cleaning brush 8 is saturated, the sub-cleaning member A is moved and brought into contact with the cleaning brush 8 to clean the cleaning brush 8.

  [Embodiment 1] FIG. 3 is a view showing a first embodiment of the sub-cleaning member A. FIG. The sub-cleaning member A-1 of the first embodiment is a cylindrical member whose axis is a direction perpendicular to the drawing, and the sub-cleaning member A-1 rotates around the axis. Further, the sub-cleaning member A-1 is moved as shown by the arrow in the drawing to come into contact with the cleaning brush 8 that is the first cleaning member. Thereby, the transfer residual toner attached to the cleaning brush 8 can be removed to clean the cleaning brush 8, and a stable high-quality image can be obtained.

  [Embodiment 2] FIG. 4 is a view showing a second embodiment of the sub-cleaning member A. In FIG. The sub-cleaning member A-2 of the second embodiment is a paddle-like member having a rotation axis in a direction perpendicular to the drawing, and the sub-cleaning member A-2 rotates around the axis. Further, the sub-cleaning member A-2 is moved as shown by the arrow in the drawing to be brought into contact with the cleaning brush 8 as the first cleaning member. Thus, the transfer residual toner attached to the cleaning brush 8 can be removed by the effect of the paddle of the sub-cleaning member A-2 to clean the cleaning brush 8, and a stable high-quality image can be obtained.

  [Embodiment 3] FIG. 5 is a view showing a third embodiment of the sub-cleaning member A. In FIG. The sub-cleaning member A-3 of the third embodiment is a member having a brush shape similar to the cleaning brush 8 and having a sticky surface. The sub-cleaning member A-3 rotates around the axis. Further, the sub-cleaning member A-3 is moved as shown by the arrow in the drawing to come into contact with the cleaning brush 8 as the first cleaning member. As a result, the transfer residual toner attached to the cleaning brush 8 can be removed by the adhesive effect of the sub-cleaning member A-3 to clean the cleaning brush 8, and a stable high-quality image can be obtained.

  [Embodiment 4] FIG. 6 is a view showing a fourth embodiment of the sub-cleaning member A. In FIG. The sub-cleaning member A-4 of the fourth embodiment is a member having a brush shape similar to the cleaning brush 8 and having a sticky surface. The sub-cleaning member A-4 rotates around the axis. Further, the position of the sub-cleaning member A-4 is fixed. By moving the cleaning brush 8-1 as the first cleaning member as shown by the arrow in the figure, the sub-cleaning member A-4 is sub-cleaned. The member A-4 is brought into contact. Thereby, the transfer residual toner attached to the cleaning brush 8-1 can be removed by the adhesive effect of the sub-cleaning member A-4 to clean the cleaning brush 8-1, and a stable high-quality image can be obtained. The sub-cleaning member A-4 may be a member similar to the first to third embodiments. The cleaning brush 8-1 is the same as the cleaning brush 8 except that it can move.

  [Embodiment 5] The following fifth embodiment will be described as a more detailed embodiment of the first to fourth embodiments. In the fifth embodiment, the cleaning brushes 8 and 8-1 are saturated by the adhered toner or paper dust, and an alert is given at the timing when the function as the first cleaning member is lowered. That is, in the fifth embodiment, the sub-cleaning members A-1 to A-3 and the cleaning brush 8-1 of the fourth embodiment are moved in the direction of the arrows shown in FIGS. Control means for controlling the drive means is provided. Further, the control means detects an operation of an operation display unit (not shown) of the printer. Then, by operating a predetermined screen switch of the operation display unit, the control unit controls the driving unit to move the sub-cleaning members A-1 to A-3 and the cleaning brush 8-1 of the fourth embodiment. Then, the cleaning brushes 8 and 8-1 are cleaned. This is a manual cleaning operation by the user.

  [Embodiment 6] The following sixth embodiment will be described as a more detailed embodiment of the first to fourth embodiments. In the sixth embodiment, in addition to the configuration of the fifth embodiment, the control unit detects the cumulative number of printed sheets in the printer. When the cumulative number of prints becomes larger than the print number threshold, an alert for alerting the user is displayed on the operation display unit. By this alert, the user can clean the cleaning brushes 8 and 8-1 by operating a predetermined screen switch of the operation display unit. Further, as a modification of the sixth embodiment, the control unit may control the driving unit without performing an alert, and an automatic cleaning operation may be performed.

  [Embodiment 7] The following seventh embodiment will be described as a more detailed embodiment of the first to fourth embodiments. In the seventh embodiment, in addition to the configuration of the fifth embodiment, the control means integrates the distance count in the printer. The distance count calculates the distance from the linear velocity in the circumferential direction of the surface of the photoconductor 3 and the time from the main motor ON that drives the photoconductor 3 to the main motor OFF, and adds it to the integrated distance. That is, distance (mm) = (time from motor ON to motor OFF for each linear velocity) × (linear velocity) is calculated. When the distance count becomes larger than the distance count threshold value, an alert for alerting the user to the operation display unit is displayed. By this alert, the user can clean the cleaning brushes 8 and 8-1 by operating a predetermined screen switch of the operation display unit. Further, as a modification of the seventh embodiment, the control unit may control the driving unit without performing an alert, and the automatic cleaning operation may be performed.

  [Eighth Embodiment] The following eighth embodiment will be described as a more detailed embodiment of the first to fourth embodiments. In the eighth embodiment, in addition to the configuration of the fifth embodiment, the control means accumulates the usage amount count in the printer. For the usage amount count, the usage amount equivalent to the sheet count and the usage amount equivalent to the distance count are calculated, and the larger one is used as the usage amount count. When this usage amount count becomes larger than the usage amount count threshold value, an alert for alerting the user to the operation display unit is displayed. By this alert, the user can clean the cleaning brushes 8 and 8-1 by operating a predetermined screen switch of the operation display unit. Further, as a modification of the eighth embodiment, the control unit may control the driving unit without performing an alert, and an automatic cleaning operation may be performed.

  [Embodiment 9] The following ninth embodiment will be described as a more detailed embodiment of the first to fourth embodiments. In the ninth embodiment, the cleaning brushes 8 and 8-1 are saturated by the toner or paper dust adhered thereto, and an alert is given at the timing when the function as the first cleaning member is lowered. That is, in the ninth embodiment, the sub-cleaning members A-1 to A-4 are movable in the longitudinal direction, and the user moves in the directions of the arrows shown in FIGS. Cleaning brushes 8 and 8-1 are cleaned by manually moving ~ A-4 in the longitudinal direction. The timing when the user manually performs the cleaning operation is preferably when the toner hopper is replaced.

  [Embodiment 10] The following tenth embodiment will be described as a more detailed embodiment of the first to fourth embodiments. In the tenth embodiment, the cleaning operation is performed at a timing when the cleaning brushes 8 and 8-1 are saturated by the toner or paper powder adhered thereto and the function as the first cleaning member is lowered. That is, in the tenth embodiment, the sub-cleaning members A-1 to A-3 and the cleaning brush 8-1 of the fourth embodiment are moved in the directions of the arrows shown in FIGS. Control means for controlling the drive means is provided. The control means has means for detecting when the toner hopper of the printer is replaced. When the toner hopper is replaced, the control means controls the driving means. Then, the sub-cleaning members A-1 to A-3 and the cleaning brush 8-1 of the fourth embodiment are moved to clean the cleaning brushes 8 and 8-1.

  [Embodiment 11] In an eleventh embodiment, in the first to tenth embodiments, the charging roller 4 as a “charging member” is fixed to the main body of the image forming apparatus, and the photosensitive member 3 and the developing means are charging members. In this embodiment, an “imaging device” comprising a certain developing device 40 can be removed.

  The present invention is not limited to the above embodiment. That is, various modifications can be made without departing from the scope of the present invention.

3 Photoconductor (latent image carrier)
4 Charging roller (charging member)
8 Cleaning brush (first cleaning member)
8-1 Cleaning brush (first cleaning member)
40 Developing device (developing means)
70 1st power supply device (1st bias supply means)
71 Second power supply (second bias supply means)
A Sub-cleaning member (second cleaning member)
A-1 Sub-cleaning member (second cleaning member)
A-2 Sub-cleaning member (second cleaning member)
A-3 Sub-cleaning member (second cleaning member)
A-4 Sub-cleaning member (second cleaning member)

JP 2004-109394 A Japanese Patent No. 4396090

Claims (6)

A latent image carrier that carries a latent image on its endlessly moving surface;
Developing means for developing the latent image on the latent image carrier with toner;
A charging member that uniformly charges the surface of the latent image carrier while moving the surface of the latent image carrier endlessly in contact with the latent image carrier;
First bias supply means for supplying a bias to the charging member;
While moving the surface of the latent image carrier in contact with the latent image carrier and the charging member on the upstream side in the rotation direction of the latent image carrier relative to the charging member, the latent image carrier and the charging member A cleaning member that collects toner adhering to the surface and cleans the surfaces of the latent image carrier and the charging member;
An image forming apparatus comprising: a second bias supply unit that supplies a bias to the cleaning member;
The cleaning member for cleaning the surfaces of the latent image carrier and the charging member is a first cleaning member,
A second cleaning member is disposed in proximity to the first cleaning member, and the first cleaning member is moved at a timing when the cleaning ability of the first cleaning member is in a saturated state. An image forming apparatus, wherein the first cleaning member is cleaned by contacting the first cleaning member.   The image forming apparatus according to claim 1, wherein the timing at which the cleaning ability of the first cleaning member is saturated is based on a count of sheets.   The image forming apparatus according to claim 1, wherein the timing at which the cleaning capability of the first cleaning member is saturated is based on a distance count.   The image forming apparatus according to claim 1, wherein the timing at which the cleaning ability of the first cleaning member is saturated is based on a usage amount count.   5. The image forming apparatus according to claim 2, wherein the timing at which the cleaning capability of the cleaning member is saturated is when the toner hopper is replaced.   The image forming apparatus according to claim 1, wherein the electric member is fixed to the main body, and an image forming apparatus including the latent image carrier and the developing unit is removable. .

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