JP4916353B2 - Image forming apparatus - Google Patents

Description

The present invention provides an image provided with a cleaning device for removing residual toner on the outer peripheral surface of a photosensitive drum serving as an image carrier in an image forming apparatus such as an electrophotographic system or an electrostatic recording system in a printing apparatus, a printer, a copying machine, or the like. More particularly, the present invention relates to an image forming apparatus provided with a cleaning device including a lubricant supply device that supplies a lubricant to the outer peripheral surface.

  Conventionally, in a photosensitive drum cleaning method using a cleaning blade in an image forming apparatus used for an electrophotographic method, residual toner remaining on a photosensitive drum serving as an image carrier is scraped off by the cleaning blade. Later, in addition to a configuration in which the transfer residual toner or the like is conveyed to a predetermined area by the brush roller, the solid lubricant is scraped and scraped by the brush roller, and then the granulated lubricant scraped by the brush roller is removed from the photosensitive drum. 2. Description of the Related Art A cleaning device that includes a lubricant application mechanism that transports and applies an ink is used.

  In such a cleaning apparatus, normally, a flicker member is provided at a portion in contact with the brush roller in order to convey the transfer residual toner collected by the brush roller and discharge it to a predetermined area. If the flicker member is not provided, the brush roller will be clogged with toner, the cleaning effect by the brush roller and the lubricant supply amount will be reduced, the cleaning property by the cleaning blade will be reduced and the photoconductor It also caused filming on the drum.

However, a separate installation space is required to provide the flicker member, and an increase in the size of the apparatus is inevitable. Therefore, a cleaning blade that contacts the photosensitive drum, and a fur brush that is disposed upstream of the cleaning blade with respect to the moving direction of the photosensitive drum and is provided so as to come into contact with the photosensitive drum are provided. Patent Document 1 discloses a cleaning device in which a cleaning blade and a fur brush are arranged so that an edge portion that does not contact the photosensitive drum at the tip portion of the blade contacts the fur brush. In this cleaning device, without providing a special flicker member, the toner collected in the fur brush is collected, the size of the device is avoided, and the collected toner is prevented from being contaminated in the image forming apparatus and the cleaning effect is not lowered. Is realized.
JP 2004-184534 A

  The cleaning device disclosed in Patent Document 1 has the above-described configuration and arrangement of the cleaning blade and fur brush, so that the cleaning blade can also serve as a flicker member. The toner collected by the brush can be collected, the apparatus can be prevented from being enlarged, and the collected toner can be prevented from being contaminated in the image forming apparatus and the cleaning effect being lowered. However, in the cleaning device, the surface of the photosensitive drum is cleaned only by physical and mechanical rubbing with the cleaning blade and the fur brush. For this reason, the life of the photosensitive drum and the intermediate transfer belt tends to be shortened due to wear due to mechanical friction with the cleaning brush and the cleaning blade.

  In order to reduce wear due to mechanical rubbing with such a cleaning brush or cleaning blade, a lubricant containing stearic acid or the like is applied to the photosensitive drum or intermediate transfer belt to reduce the friction coefficient of these surfaces. Generally, it is practiced to reduce the wear and reduce the wear. At this time, in order to surely reduce the friction of the photosensitive drum and the intermediate transfer belt, it is preferable that the lubricant adheres uniformly and uniformly to the outer peripheral surface of the photosensitive drum.

In view of the above problems, an object of the present invention is to provide an image forming apparatus in which a lubricant is uniformly and firmly adhered to the outer peripheral surface of a photosensitive drum and the size of the apparatus can be avoided.

In order to solve the above problems, the present invention removes residual toner on the image carrier after the toner image formed on the image carrier to be rotated is transferred, and lubricates the outer peripheral surface of the image carrier. An image forming apparatus provided with a cleaning device for supplying an agent,
The cleaning device is a lubricant to be supplied to the image carrier and is a solid lubricant in a solid state;
A cleaning blade in which at least a part of the tip portion is in contact with the outer peripheral surface of the image carrier;
Arranged in contact with the image carrier upstream of the cleaning blade with respect to the rotation direction of the image carrier, the solid lubricant is scraped off by rotating in one direction to remove the lubricant from the image carrier. A brush roller to be applied to the body;
A guide member for guiding the solid lubricant so as to contact the brush roller;
A holding member for holding the solid lubricant;
A lubricant pressing member that moves the solid lubricant while pressing the solid lubricant against the brush roller from the back side of the holding member,
Of the tip portion of the cleaning blade, an edge portion that is not in contact with the image carrier is disposed so as to contact the brush roller,
The holding member, the solid lubricant in advance in the state of abutting surface of the brush roller of the solid lubricant is inclined at a predetermined angle in the forward direction with respect to the rotation direction of the brush roller, the brush roller Holding the solid lubricant so that the center of the solid lubricant coincides with the central axis of the brush roller from the state inclined at the predetermined angle during rotation of
The guide member is a pre-Symbol image forming apparatus characterized by the solid lubricant is to guide the retaining member to move toward the central axis of the brush roller.

  With such a configuration, the cleaning blade that scrapes off the transfer residual toner on the photosensitive drum also serves as a conventional flicker that discharges the clogged toner on the brush roller. It is not necessary to separately provide a flicker provided for discharging the clogged toner to the brush roller, and the enlargement of the cleaning device can be avoided. Also, by having a mechanism for supplying the lubricant, the adhesion between the photosensitive drum and the toner by the lubricant is reduced, thereby improving the cleaning property and fixing the toner component to the outer peripheral surface of the photosensitive drum (so-called “so-called”). The occurrence of filming can be suppressed.

In the present invention, the solid lubricant is held to a predetermined angle inclined in the forward direction with respect to the rotation direction of the abutment surface is brush roller and the brush roller of the solid lubricant.

  With this configuration, when the solid lubricant flows in the rotation direction and tilts when the brush roller rotates, the center of the solid lubricant is arranged on the normal line of the brush roller. It is possible to consume evenly and efficiently in the part that contacts the upstream side in the rotational direction and the part that contacts the downstream side in the rotational direction. Therefore, the solid lubricant can be made the minimum size necessary for performance, and the cleaner unit and the process cartridge can be expected to be miniaturized.

In the above present invention, the guide member may have a be guided to move in a direction toward the solid lubricant to the central axis of the brush roller.

  By adopting such a configuration, when the solid lubricant is tilted upstream with respect to the direction of rotation of the brush roller, the slide member is tilted. Since it is not necessary, it is possible to save the space necessary for the movement, and the process cartridge can be reduced in size.

  At this time, in the above-described embodiment, the contact surface of the solid lubricant with the brush roller may be a concave curved surface.

  By adopting such a configuration, it becomes possible to suppress the peak of the initial consumption of the solid lubricant, so that excessive supply to the image carrier is prevented in advance and stable throughout. In addition, the lubricant can be supplied to the image carrier.

  At this time, in the above embodiment, a toner intrusion prevention member for preventing toner from entering the contact surface is provided upstream of the contact surface of the brush roller with the solid lubricant in the rotation direction. Also good.

  With such a configuration, it becomes possible to prevent the inside of the apparatus from being filled with toner, to stabilize the contact pressure to the brush roller, and to stabilize the amount of lubricant supplied to the image carrier. It will be possible.

  In order to solve the above-described problem, according to another embodiment of the present invention, an image forming apparatus including an intermediate transfer member, including the cleaning device according to any one of the above-described embodiments. A forming apparatus is provided.

  By adopting such a configuration, as the size of the cleaning device is reduced, the size of the image forming apparatus is also prevented from being increased, and transfer to the intermediate transfer member is improved by improving the releasability of the image carrier surface from the toner. This improves the image quality and makes it possible to obtain good image quality.

  As described above, according to the present invention, one edge portion of the tip portion of the cleaning blade is brought into contact with the brush roller, and the other edge portion of the tip portion is applied to the outer peripheral surface of the photosensitive drum with the brush roller. Since the lubricant containing acid or the like is immediately spread, a thin layer of lubricant is surely formed on the outer peripheral surface of the photosensitive drum while discharging the clogged toner to the brush roller with only the cleaning blade. For this reason, it is not necessary to separately provide a flicker for discharging clogged toner to the brush roller, so that an increase in the size of the cleaning device can be avoided and a thin film of lubricant can be reliably formed on the outer peripheral surface of the photosensitive drum. Thus, it becomes possible to further improve the cleaning property and suppress the occurrence of filming.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  First, the configuration of a first embodiment of an image forming apparatus in which a lubricant supply device according to the present invention is used will be described with reference to the drawings. FIG. 1 is an explanatory diagram showing an overall configuration of a first embodiment of an image forming apparatus in which a lubricant supply device according to the present invention is used.

  The image forming apparatus 100 forms a multicolor or single color image on a predetermined sheet (recording paper) based on image data input from the outside or image data obtained by reading a document.

  As shown in the figure, the image forming apparatus 100 includes an exposure unit 1, a developing device 2, a photosensitive drum 4, a charger 5, a cleaner unit 4, an intermediate transfer belt unit 8, a fixing unit 12, a sheet conveyance path S, a supply path. A paper tray 10 and a paper discharge tray 15 are provided.

  The image data of a color image handled in the image forming apparatus 100 corresponds to a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y). Therefore, the developing device 2 (2a, 2b, 2c, 2d), the photosensitive drum 3 (3a, 3b, 3c, 3d), the charger 5 (5a, 5b, 5c, 5d), the cleaner unit 4 (4a, 4b, 4c and 4d) are provided four by four so as to form four types of latent images corresponding to the respective colors. The symbols a to d correspond to a being black, b being cyan, c being magenta, and d being yellow. It is configured.

  The photosensitive drum 3 is disposed above the exposure unit 1 and is a substantially cylindrical image carrier, and is controlled to rotate in a predetermined direction by a driving unit and a control unit (not shown). The photosensitive drum 3 is configured by forming a photoconductive layer on a base material. For example, a metal drum made of aluminum or the like is used as a base material, and a photoconductive layer such as amorphous silicon (a-Si), selenium (Se), or an organic photo semiconductor (OPC) is formed in a thin film on the outer peripheral surface thereof. ing. The configuration of the photosensitive drum 3 is not particularly limited to the above-described configuration.

  The charger 5 (5a, 5b, 5c, 5d) is a charging means for uniformly charging the surface of the photosensitive drum 3 to a predetermined potential, and is close to the outer peripheral surface below the photosensitive drum 3. Has been placed. In the present embodiment, the contact type roller type charger 5 as shown in FIG. 1 is used, but a charger type or brush type charger may be used instead.

  The exposure unit 1 exposes the charged photosensitive drum 3 according to the input image data, thereby forming an electrostatic latent image corresponding to the image data on the surface of the photosensitive drum 3. In the present embodiment, as shown in FIG. 1, the exposure unit 1 uses a laser scanning unit (LSU) provided with a laser irradiation unit and a reflection mirror, but the light emitting elements are arranged in an array. For example, a method using an EL or LED writing head may be used.

  Each developing device 2 (2a, 2b, 2c, 2d) visualizes the electrostatic latent image formed on each photoconductor drum 3 with toners of K, C, M, and Y colors.

  The cleaner unit 4 (4a, 4b, 4c, 4d) removes the toner remaining on the surface of the photosensitive drum 3 after the development and image transfer steps by using a lubricant or the like, and collects the outer periphery of the photosensitive drum 3 It has a function as a cleaning device that removes residual toner on the surface. Further, as will be described later, a lubricant supply device 40 that supplies a lubricant to the outer peripheral surface of the photosensitive drum 3 by using a solid lubricant 41 (41a, 41b, 41c, 41d) disposed inside the cleaner unit 4. It also has a function as. A detailed description of the configuration of the cleaner unit 4 will be given later.

  An intermediate transfer belt unit 8 serving as an intermediate transfer member is disposed above the photosensitive drum 3. The intermediate transfer belt unit 8 includes an intermediate transfer roller 6 (6a, 6b, 6c, 6d), an intermediate transfer belt 7, an intermediate transfer belt driving roller 71, an intermediate transfer belt driven roller 72, an intermediate transfer belt tension mechanism 73, and an intermediate transfer belt. A transfer belt cleaning unit 9 is provided.

  The intermediate transfer belt 6, the intermediate transfer belt driving roller 71, the intermediate transfer belt driven roller 72, the intermediate transfer belt tension roller 73, and the like stretch the intermediate transfer belt 7 and rotate it in the direction of arrow B shown in FIG. It is.

  The intermediate transfer roller 6 is rotatably supported by an intermediate transfer roller mounting portion of the intermediate transfer belt tension mechanism 73 of the intermediate transfer belt unit 8. In order to transfer the toner image onto the intermediate transfer belt 7, a high voltage is used. A transfer bias (a high voltage having a polarity opposite to the toner charging polarity (-) (+)) is applied. At this time, the transfer efficiency when there is no supply of lubricant from the cleaner unit 4 is 94%, and there is also a phenomenon that characters are missing, but when the lubricant is supplied from the cleaner unit 4, The transfer efficiency was improved to 98%, and various problems such as missing characters were also improved.

  In this embodiment, the intermediate transfer roller 6 is formed based on a metal shaft made of stainless steel having a diameter of 8 to 10 mm, and the surface thereof is covered with a conductive elastic material such as EPDM or urethane foam. It is a roller. With this conductive elastic material, the intermediate transfer roller 6 can uniformly apply a high voltage to the intermediate transfer belt 7. In the present embodiment, the intermediate transfer roller 6 is used as the transfer electrode, but a brush or the like can be used in addition thereto.

  The intermediate transfer belt 7 is provided so as to be in contact with each photosensitive drum 3 (3a, 3b, 3c, 3d). A color toner image (multicolor toner image) is formed on the intermediate transfer belt 7 by sequentially transferring the toner images of the respective colors formed on the photosensitive drum 3 in a superimposed manner. The intermediate transfer belt 7 is formed in an endless shape using a film having a thickness of about 100 μm to 150 μm.

  As described above, the electrostatic latent images on the respective photosensitive drums 3 (3a, 3b, 3c, 3d) are visualized with toners corresponding to the respective hues, and then become toner images, respectively. Are stacked on the intermediate transfer belt 7. As described above, the stacked toner images are moved to a contact position between the conveyed sheet and the intermediate transfer belt 7 by the rotation of the intermediate transfer belt 7, and the sheet is transferred by the transfer roller 11 disposed at this position. Transcribed above. In this case, the intermediate transfer belt 7 and the transfer roller 11 are pressed against each other at a predetermined nip, and a voltage for transferring the toner image onto the paper is applied to the transfer roller 11. This voltage is a high voltage having a polarity (+) opposite to the charging polarity (−) of the toner.

  In order to constantly obtain the nip, either the transfer roller 11 or the intermediate transfer belt drive roller 71 is made of a hard material such as metal, and the other is a soft material such as an elastic roller (elastic rubber roller or foaming resin). Roller).

  Due to the contact between the intermediate transfer belt 7 and the photosensitive drum 3, the toner adhering to the intermediate transfer belt 7 and the toner image transferred from the intermediate transfer belt 7 to the paper are not transferred but remain on the intermediate transfer belt 7. The toner is removed and collected by the intermediate transfer belt cleaning unit 9 because it causes toner color mixing in the next process. The intermediate transfer belt cleaning unit 9 includes a cleaning blade 9 a as a cleaning member that contacts the intermediate transfer belt 7. The portion of the intermediate transfer belt 7 in contact with the cleaning blade 9a is supported by the intermediate transfer belt driven roller 72 from the back side.

  The paper feed tray 10 is a tray for storing sheets (recording paper) used for image formation, and is provided below the image forming unit and the exposure unit 1. The manual feed tray 20 is a tray for storing sheets (recording paper) used for image formation, and is provided on a side surface of the image forming apparatus 100. On the other hand, a paper discharge tray 15 provided on the upper side of the image forming apparatus 100 is a tray for placing printed sheets face down.

  Further, the image forming apparatus 100 is provided with a sheet conveyance path S for sending the sheets in the paper feed tray 10 and the sheets in the manual feed tray 20 to the paper discharge tray 15 via the transfer unit 11 and the fixing unit 12. . A pickup roller 16, a registration roller 14, a transfer unit including a transfer roller 11, a fixing unit 12, a conveyance roller 25, and the like are disposed in a portion from the sheet feeding tray 10 to the sheet discharge tray 15 in the sheet conveyance path S. ing.

  The conveyance rollers 25 (25-1, 25-2, 25-3, 25-4, 25-5, 25-6, 25-7, 25-8) are small-sized to promote and assist the conveyance of the sheet. A plurality of rollers are provided along the sheet conveyance path S. The pickup rollers 16 (16-1 and 16-2) are provided at the ends of the paper feed tray 10 and the manual feed tray 20, and supply sheets one by one from the paper feed tray 10 and the manual feed tray 20 to the sheet conveyance path S. It is a drawing roller. The registration roller 14 temporarily holds the sheet conveyed in the sheet conveyance path S, and conveys the sheet to the transfer unit at a timing when the leading edge of the toner image on the photosensitive drum 3 and the leading edge of the sheet are aligned. That is, the registration roller 14 conveys the sheet so that the leading edge of the toner image on the transfer belt 7 is aligned with the leading edge of the image forming range on the sheet based on a detection signal output from a pre-registration detection switch (not shown). Is set to

  The fixing unit 12 includes a heating roller 31, a pressure roller 32, and the like. The heating roller 31 and the pressure roller 32 rotate with the sheet interposed therebetween. The heating roller 31 is controlled by a control unit (not shown) provided in the image forming apparatus 1A so as to have a predetermined fixing temperature. This control unit controls the heating roller 31 based on a detection signal from a temperature detector (not shown). The heating roller 31 heat-presses the sheet together with the pressure roller 32 to melt, mix, and press the color toner images transferred to the sheet, and heat-fix the sheet. The sheet on which the multicolor toner image (each color toner image) has been fixed is conveyed to the reverse sheet discharge path of the sheet conveyance path S by the plurality of conveyance rollers 25 and is reversed (the multicolor toner image is on the lower side). Are discharged onto the paper discharge tray 15.

  Next, details of the configuration of the cleaner unit and the lubricant supply device provided in the cleaner unit in the present embodiment will be described with reference to the drawings. FIG. 2 is a diagram showing a schematic configuration of the cleaner unit in the present embodiment, and FIG. 3 is a diagram in which a holder portion for holding a fixed lubricant provided in the lubricant supply device included in the cleaner unit of the present embodiment is a guide. It is a figure which shows the structure of the principal part of the site | part supported by a part.

  The cleaner unit 4 uses a cleaning blade 46 to scrape off, remove and collect the toner remaining on the surface of the photosensitive drum 3 after development and image transfer, and then to the outside of the cleaner unit 4 by the toner conveying screw 48. To be discharged. Further, the configuration includes a lubricant supply device 40 that supplies a lubricant to the outer peripheral surface of the photosensitive drum 3 using a solid lubricant 41 provided in the cleaner unit 4.

  The cleaning blade 46 is formed of a material having high wear resistance and contamination resistance, such as urethane rubber, and has a function of scraping and removing the transfer residual toner on the surface of the photosensitive drum 3 and a granularity by the brush roller 42. The lubricant applied to the outer peripheral surface of the photosensitive drum 3 is applied to a wide area of the outer peripheral surface. When applying the granulated lubricant with the cleaning blade 46, the tip edge portion 46b of the cleaning blade 46 spreads the granulated lubricant on the outer peripheral surface of the photosensitive drum 3 so that the lubricant is thinned. . A detailed description of the cleaning blade 46, which is a characteristic part of the present embodiment, will be described later.

  The lubricant supply device 40 rotates in one direction (the b direction shown in FIG. 2), granulates while rubbing against the solid lubricant 41, and applies the granulated lubricant to the outer peripheral surface of the photosensitive drum 3. A brush roller 42 that guides the solid lubricant 41 in a fixed direction (direction c shown in FIG. 2) so that the solid lubricant 41 contacts the brush roller 42, and a holder (holding member) 45 that holds the solid lubricant 41. And a compression coil spring (lubricant) that moves the solid lubricant 41 in a certain direction (c direction shown in FIG. 2) while pressing the solid lubricant 41 against the brush roller 42 from the back side of the holder 45. Pressing member) 47.

  The brush roller 42 is in contact with the outer peripheral surface of the photosensitive drum 3 and the solid lubricant 41 and rotates in a certain direction (the b direction shown in FIG. 2), so that the solid lubricant 41 is rubbed against the solid lubricant 41. The agent 41 is scraped and granulated, and the granulated lubricant is supplied to the photosensitive drum 3. The brush roller 42 is formed by laying fibers made of polyester fibers or the like formed in a loop shape with a hair leg length of 5 mm on the outer periphery of a stainless steel core bar 42 a having a diameter of 6 mm to form a brush portion 42 b. A roll brush with a diameter of 16 mm is used. The brush roller 42 is supported so that both end shafts are freely rotatable and arranged in parallel with the shaft of the photosensitive drum 3, and is rotatable with the front end of the polyester fiber in contact with the outer peripheral surface of the photosensitive drum 3. Is provided.

  The brush roller 42 is always in contact with the photosensitive drum 3 and has a function of removing and collecting the toner remaining on the surface of the photosensitive drum 3 while the brush roller 42 itself is driven to rotate. Further, in order to make it easy to scrape off the residual toner adhering to the photosensitive drum 3 on the cleaning blade 46 side, the solid lubricant 41 containing zinc stearate as a main component that promotes the peeling of the toner is driven by rotation. It has a function of granulating while rubbing and applying the granulated lubricant to the outer peripheral surface of the photosensitive drum 3. Further, in the present embodiment, the cleaning blade 46 and the brush roller 42 are disposed so as to contact each other, and specifically, an edge of the tip portion of the cleaning blade 46 that is not in contact with the photosensitive drum 3. The portion 46a is disposed so as to contact the brush roller 42. That is, the edge portion 46 a opposite to the edge portion 46 b that is in contact with the photosensitive drum 3 at the tip portion of the cleaning blade 46 is disposed so as to bite into the brush roller 42. In addition, the dimension of each component 42a, 42b of the brush roller 42 mentioned above is an Example, and can also be comprised by another dimension.

  A solid lubricant 41 is disposed on the outer peripheral side of the brush roller 42 in the radial direction. In the present embodiment, the solid lubricant 41 is formed by melting a material mainly composed of zinc stearate and then cooling and solidifying it to form a horizontally long plate. The solid lubricant 41 is pressed and urged by the compression coil spring 47 in the axial direction of the brush roller 42. In the present embodiment, as shown in FIG. 2, the solid lubricant 41 is directed toward the rotation axis of the rotating brush roller 42 by the elastic force of the compression coil spring 47 via the slider 44 connected to the compression coil spring 47. It is pressed and biased toward (c direction shown in FIG. 2). As the lubricant pressing member that presses and urges the solid lubricant 41 in the axial direction of the brush roller 42, other elastic members such as a leaf spring can be applied in addition to the compression coil spring 47 described above. .

  At that time, the contact surface of the solid lubricant 41 is inclined at a predetermined angle θ toward the forward direction (direction a shown in FIG. 2) with respect to the rotation direction of the brush roller 42 (direction b shown in FIG. 2). A fixed lubricant 41 is held. The angle θ at that time is preferably at least 5 degrees or more, more preferably in the range of 5 to 15 degrees, although it depends on the components and properties of the solid lubricant 41 in order to obtain a substantial effect. The solid lubricant 41 is pressed and urged against the surface of the brush roller 42 with a constant load by the compression spring 47 disposed on the back surface of the holder 45.

  In the present embodiment, the holder 45 for fixing the fixed lubricant 41 is held so as to be inclined at a predetermined angle θ with respect to the bottom surface 43 b of the guide member 43. The holder 45 is provided substantially in parallel with the rotation axis along the rotation axis direction of the brush roller 42. Both end portions 45a of the holder 45 are supported by guide members 43 that guide the reciprocating motion in a direction toward the rotation axis of the brush roller 42 (direction c shown in FIG. 2).

  When the both ends 45a of the holder 45 are supported by the guide member 43, the guide member 43 may directly support the holder 45. However, in order to facilitate assembly and the like, as shown in FIGS. In addition, the guide member 43 preferably supports the holder 45 via the slider 44.

  As shown in FIG. 3, the guide member 43 is formed with a gap portion 43a for sliding the slider 44 in a certain direction. The end portion 44a of the slider 44 is inserted into the gap portion 43a, and the guide member 43 The slider 44 is slid in a certain direction along the gap portion 43a. That is, in the present embodiment, the slider 44 joined to the solid lubricant 41 is movable along the gap 43a of the guide member 43 in the direction of separating from and contacting the brush roller 42. Therefore, the solid lubricant 41 Can be guided in a direction toward the central axis of the brush roller 42.

  The slider 44 is formed with a sloped portion 44 c that contacts the back surface portion 45 b of the holder 45 at a portion inside the guide member 43 of the slider 44 when supported by the guide member 43. The inclined surface portion 44c is inclined at a predetermined angle θ with respect to the bottom surface portion 44b of the slider 44 in the forward direction of the rotation direction of the brush roller 42 (direction a shown in FIG. 2). In order to stabilize the joining with the holder 45, a convex portion 44d that fits into the hole 45c formed in both end portions 45a of the holder 45 is provided at the approximate center of the slope portion 44c. As described above, in the present embodiment, the solid lubricant 41 fixed to the holder 45 is always kept in a predetermined state by joining both end portions 45a of the holder 45 that fixes the fixed lubricant 41 to the inclined surface portion 44c of the slider 44. It can be inclined at an angle θ. In order to incline the solid lubricant 41 at the angle θ, although not shown, a slope portion may be provided on the contact surface of the holder 45 with the slider 44.

  In such a configuration, the granulated lubricant, which is fine particles of the solid lubricant 41 scraped off by rubbing with the brush roller 42, is conveyed to the outer peripheral surface of the photosensitive drum 3 by the brush roller 42. In this embodiment, 25 to 40 μg of granulated lubricant per sheet (recording paper) is supplied to the photosensitive drum 3.

  Here, in the conventional case, when the solid lubricant 41 is scraped off by the rubbing of the brush roller 42, the solid lubricant 41 is inclined unintentionally in the rotation direction of the brush roller 42. For this reason, consumption is biased to the solid lubricant 41 on the upstream side in the rotational direction of the brush roller 42 with which the solid lubricant 41 abuts, and the life of the image forming apparatus 100 is slightly consumed on the downstream side in the rotational direction. Most of them remain without being consumed even at the end.

  On the other hand, in the lubricant supply device 40 of the present embodiment, the solid lubricant 41 is tilted in advance so as to incline at a predetermined angle θ in the forward direction of the rotation direction of the brush roller 42. Thus, when the brush roller 42 rotates, the center of the solid lubricant 41 coincides with the center axis of the brush roller 42, that is, is arranged on the normal line of the brush roller 42, so the contact surface of the solid lubricant 41 with the brush roller 42 It is possible to make contact and consumption evenly over the entire width of the. For this reason, since the solid lubricant 41 can be made the minimum necessary size in terms of performance, the cleaner unit and the process cartridge can be expected to be miniaturized.

  Further, in order to incline the solid lubricant 41, the contact surface with the bottom surface portion 45 b of the holder 45 that fixes the solid lubricant 41 becomes a slope portion 44 b that forms a predetermined angle θ with respect to the bottom surface portion 44 b of the slider 44. Therefore, the solid lubricant 41 can be tilted by a predetermined angle while the guide member 43 is disposed so as to move in the direction of the central axis of the brush roller 42. Thereby, in order to incline the solid lubricant 41 by a predetermined angle, an extra space for moving the guide member 43 in the rotational direction is not required. Therefore, the cleaner unit 4 can be downsized, and the process cartridge including the cleaner unit 4 can be used. Can be reduced in size.

  As shown in FIG. 2, a toner shield 49 serving as a toner intrusion preventing member for preventing toner from entering the contact surface is provided upstream of the contact surface of the brush roller 42 with the solid lubricant 41 in the rotation direction. Is provided. When the toner shield 49 is not provided in the cleaner unit, the toner enters the periphery of the members related to the lubricant supply such as the solid lubricant 41 and the holder 45. For this reason, pressurization of the solid lubricant 41 against the brush roller 42 is hindered, and a large amount of toner intervenes on the sliding contact surface of the solid lubricant 41. Therefore, as shown in the broken line graph of FIG. In addition, the lubricant supply amount decreases and becomes unstable. In this embodiment, the toner shield 49 is provided on the upstream side in the rotational direction from the contact surface of the brush roller 42 with the solid lubricant 41 in the case where the toner enters the periphery of the member related to the lubricant supply. As a result, as shown in the solid line graph of FIG. 4, the toner shield 49 prevents the toner from entering the lubricant supply device 40, stabilizes the contact pressure on the brush roller 42, and increases the amount of lubricant supplied. Achieve stabilization.

  As described above, the brush roller 42 has a function of removing and collecting toner remaining on the surface of the photosensitive drum 3 itself. Further, the brush roller 42 has a function of facilitating scraping on the cleaning blade 46 side or a function of promoting toner peeling. As described above, the brush roller 42 is always placed in an environment in contact with the remaining toner on the outer peripheral surface of the photosensitive drum 3, and the toner clogging in the brush roller 42 occurs over time. It becomes easy to do. For this reason, the toner removal / collection ability on the surface of the photosensitive drum 3 is reduced, and the consumption of the fixed lubricant 41 per sheet decreases as the toner slips through and the number of printed sheets increases, that is, the lubricant. This leads to a decrease in the supply amount.

  In order to deal with such a case, in the present embodiment, the edge portion 46 a that is not in contact with the photosensitive drum 3 in the tip portion of the cleaning blade 46 is disposed so as to be in contact with the brush roller 42. That is, the edge 46 a opposite to the edge 46 b of the cleaning blade 46 that is in contact with the photosensitive drum 3 is arranged so that the edge 46 a of the brush roller 42 bites into the brush 42 b. For this reason, since the edge portion 46a is always in a position in contact with the brush roller 42, the toner accumulated in the brush portion 42b of the brush roller 42 can be scraped and discharged. Accordingly, since the brush roller 42 rubs the solid lubricant 41 in a state where it is constantly refreshed, the amount of lubricant supplied can be stabilized, and the same operation as in the initial stage of use can be maintained. It comes to be.

  In other words, in this embodiment, the cleaning blade 46 is configured and arranged as described above, so that the toner accumulated in the brush roller 42 in the conventional cleaning device is scraped and discharged as a flicker that is a toner discharge member. It will also have a role. For this reason, since the cleaning blade 46 of the present embodiment also serves as a conventional flicker, the number of parts in the cleaning unit 4 can be reduced, and an increase in the size of the apparatus can be avoided.

  Further, in the present embodiment, the cleaning blade 46 is applied to the photosensitive drum 3 by the brush roller 42 on the other edge portion 46 b of the tip portion, that is, the edge portion 46 b on the side contacting the photosensitive drum 3. In order to reduce the thickness of the granulated lubricant that has been pressed, it is installed close to the brush roller 42. In this way, by installing the cleaning blade 46 so as to be in constant contact with the brush roller 42, the granular lubricant applied from the brush roller 42 to the outer peripheral surface of the photosensitive drum 3 is immediately applied to the tip portion of the cleaning blade 46. It becomes possible to form a thin film by pushing the edge portion 46b.

  Conventionally, since the brush roller and the cleaning blade are disposed apart from each other, the granular lubricant applied on the photosensitive drum from the brush roller is conveyed to the nip portion which becomes the tip portion of the cleaning blade by the rotational driving of the photosensitive drum. After that, it was thinned by being spread by a cleaning blade. Therefore, the lubricant reaches the cleaning blade by the transfer residual toner that is always conveyed from the upstream in the rotation direction of the photosensitive drum until the granular lubricant applied on the photosensitive drum reaches the nip portion. Was sometimes disturbed.

  On the other hand, in the cleaner unit 4 of the present embodiment, the brush roller 42 is always in contact with the cleaning blade 46 that is the final arrival point of the granulated lubricant, so that the granulated lubricant is cleaned by the transfer residual toner. This prevents the blade 46 from being prevented from reaching the tip portion in advance. For this reason, since the granulated lubricant is efficiently supplied to the nip portion between the leading edge portion 46b of the cleaning blade 46 and the photosensitive drum 3, a thin film of the lubricant can be reliably formed on the outer peripheral surface of the photosensitive drum 3. It becomes like this.

  That is, the lubricant film is surely formed on the outer peripheral surface of the photosensitive drum 3 while discharging the toner clogged to the brush roller 42 only by the cleaning blade 46. In other words, since the cleaning blade 46 is always in contact with the brush roller 42, one edge portion 46 a of the tip portion of the cleaning blade 46 contacts the brush roller 42, while the tip portion of the cleaning blade 46 The other edge portion 46b immediately spreads the granulated lubricant applied to the outer peripheral surface of the photosensitive drum 3, so that a thin film of lubricant containing stearic acid or the like is surely distributed evenly on the outer peripheral surface of the photosensitive drum 3. Will be formed. For this reason, it becomes possible to further improve the cleaning property and suppress the occurrence of filming.

  In the present embodiment, the solid lubricant 41 is formed as a horizontally long plate extending in a direction parallel to the axial direction of the brush roller 42 or the photosensitive drum 3 as described above. The solid lubricant 41 normally supplies 25 to 40 μg of lubricant fine particles per sheet (recording paper) to the photosensitive drum 3.

  In this case, if the contact surface of the solid lubricant 41 that slides on the brush roller 42 is a flat surface, the contact area with the brush roller 42 is small and the surface pressure is high. Therefore, the solid lubricant 41 is excessively consumed and supplied until the shape of the solid lubricant 41 follows the outer peripheral shape of the brush roller 42, that is, at a relatively early stage, as indicated by the broken line graph of FIG. Is done. Such excessive consumption of the solid lubricant 41, that is, excessive supply of the lubricant to the photosensitive drum 3, causes a reduction in image quality due to toner scattering during transfer, which is a subsequent process.

  In contrast, in this embodiment, as shown in FIG. 3, the contact surface 41 a of the solid lubricant 41 with the brush roller 42 is formed on a concave curved surface that matches the shape of the outer peripheral surface of the brush roller 42. Thus, as shown in the solid line graph of FIG. 5, excessive consumption of the solid lubricant 41 in the initial stage, that is, excessive supply of the lubricant to the photosensitive drum 3 is suppressed, and the photosensitive drum 3 is continuously supplied throughout. A stable lubricant can be supplied to the outer peripheral surface.

  As the solid lubricant 41 used in the lubricant supply device 40 of the present embodiment, in addition to the aforementioned zinc stearate, barium stearate, lead stearate, nickel stearate, cobalt stearate, iron stearate, Copper stearate, strontium stearate, calcium stearate, cadmium stearate, magnesium stearate, manganese oleate, iron oleate, cobalt oleate, lead oleate, magnesium oleate, copper oleate, zinc palmitate, cobalt palmitate , Relatively higher fatty acids such as copper palmitate, magnesium palmitate, aluminum palmitate, calcium palmitate, lead cabrylate, lead cabronate, zinc linolenate, cobalt linolenate, cadmium linolenate It is also possible to use. Natural waxes such as colloidal high-temperature silica powder and carnauba wax can also be used.

  As described above, the cleaning unit 4 of the present embodiment is arranged so that the cleaning blade 46 is always in contact with the brush roller 42, so that one edge portion 46 a of the tip portion of the cleaning blade 46 is attached to the brush roller 42. The edge part 46a discharges the clogged toner on the brush roller 42, and the other edge part 46b at the tip part presses the lubricant applied to the outer peripheral surface of the photosensitive drum 3 by the brush roller 42. In other words, the lubricant thin film can be reliably formed on the outer peripheral surface of the photosensitive drum 3 while discharging the toner clogged to the brush roller 42 only by the cleaning blade 46. In other words, the cleaning blade 46 that scrapes off the transfer residual toner on the outer peripheral surface of the photosensitive drum 3 also functions as a conventional flicker that discharges the clogged toner on the brush roller 42, and on the outer peripheral surface of the photosensitive drum 3. A thin film of lubricant is surely formed evenly.

  That is, in a conventional cleaning device having a flicker as a toner discharging member, since there is a distance from the brush roller to the cleaning blade, the lubricant containing stearic acid and the like adhering to the photosensitive drum is in a powder form and photosensitive. Since it was merely placed lightly on the photosensitive drum, the adhesive force of the lubricant to the photosensitive drum was weak, and the possibility of being discharged together with the residual toner was high.

  However, in the present embodiment, the brush roller 42 and the cleaning blade 46 are in contact with each other, and the granulated lubricant applied to the outer peripheral surface of the photosensitive drum 3 by the brush roller 42 is applied to the front edge portion 46b of the cleaning blade 46. It has a structure that can be expanded immediately. Therefore, a lubricant thin film containing stearic acid or the like can be reliably formed on the outer peripheral surface of the photosensitive drum 3. Therefore, improvement in the cleaning property of the photosensitive drum and suppression of filming can be further realized. Further, since the lubricant can be efficiently applied to the outer peripheral surface of the photosensitive drum, it is possible to suppress the supply of useless lubricant and to improve the life of the solid lubricant.

  Further, in the conventional cleaning device, it is not necessary to separately provide a flicker provided for discharging the clogged toner to the brush roller, so that an increase in the size of the cleaning device can be avoided.

  In addition, as the cleaning device for the photosensitive drum of the image forming apparatus including the intermediate transfer member, the cleaning unit 4 according to the present embodiment is used, so that the size of the image forming apparatus increases as the cleaning apparatus is downsized. This is avoided and the releasability of the outer peripheral surface of the photosensitive drum to the toner is improved, so that the transferability to the intermediate transfer member is improved, and a good image quality can be obtained.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, in the first embodiment, the cleaning device of the present invention is applied to a small-sized printer that can be placed on the desktop as shown in FIG. 1 as an image forming device. However, various functions such as a printer, a FAX, and a scanner are provided. The cleaning apparatus of the present invention can also be applied to a large type image forming apparatus such as a multifunction peripheral.

1 is an explanatory diagram showing the overall configuration of a first embodiment of an image forming apparatus in which a cleaning device according to the present invention is used. It is a figure which shows schematic structure of the cleaner unit in the embodiment. It is a figure which shows the structure of the principal part of the site | part by which the holder part holding the fixed lubricant with which the lubricant supply apparatus contained in the cleaner unit of the embodiment is supported by a guide part is shown. 6 is a graph comparing consumption of a fixed lubricant with and without a toner intrusion prevention member. It is the graph which compared the consumption of the solid lubricant by the difference in a solid lubricant shape.

Explanation of symbols

3 Image carrier (photosensitive drum)
4 Cleaning device (cleaner unit)
40 Lubricant supply device 41 Solid lubricant 41a Contact surface 42 Brush roller 43 Guide member 45 Holding member (holder)
46 Cleaning blade 46a Edge portion 47 Lubricant pressing member (compression coil spring)
49 Toner Intrusion Prevention Member (Toner Shield)
100 Image forming apparatus

Claims (4)

Image formation provided with a cleaning device that removes residual toner on the image carrier after transferring the toner image formed on the image carrier to be rotated and supplies lubricant to the outer peripheral surface of the image carrier A device,
The cleaning device is a lubricant to be supplied to the image carrier and is a solid lubricant in a solid state;
A cleaning blade in which at least a part of the tip portion is in contact with the outer peripheral surface of the image carrier;
Arranged in contact with the image carrier upstream of the cleaning blade with respect to the rotation direction of the image carrier, the solid lubricant is scraped off by rotating in one direction to remove the lubricant from the image carrier. A brush roller to be applied to the body;
A guide member for guiding the solid lubricant so as to contact the brush roller;
A holding member for holding the solid lubricant;
A lubricant pressing member that moves the solid lubricant while pressing the solid lubricant against the brush roller from the back side of the holding member,
Of the tip portion of the cleaning blade, an edge portion that is not in contact with the image carrier is disposed so as to contact the brush roller,
The holding member, the solid lubricant in advance in the state of abutting surface of the brush roller of the solid lubricant is inclined at a predetermined angle in the forward direction with respect to the rotation direction of the brush roller, the brush roller Holding the solid lubricant so that the center of the solid lubricant coincides with the central axis of the brush roller from the state inclined at the predetermined angle during rotation of
It said guide member, an image forming apparatus, characterized in that the pre-Symbol solid form lubricant is for guiding the holding member to move in a direction toward the center axis of the brush roller.   The image forming apparatus according to claim 1, wherein a contact surface of the solid lubricant with the brush roller forms a concave curved surface.   The toner intrusion prevention member for preventing intrusion of toner to the contact surface is provided on the upstream side in the rotation direction from the contact surface of the brush roller with the solid lubricant. The image forming apparatus according to 2.   The image forming apparatus according to claim 1, further comprising an intermediate transfer member.

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