JP2011027969A - Cleaning device, image forming apparatus, and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent toner leakage at the end part of a cleaning blade 63 and to improve lubricity between the cleaning blade and a photoreceptor contacting part at the blade end while maintaining effect for removing toner adhering to a photoreceptor 1 to prevent peeling in the cleaning blade end. <P>SOLUTION: A seal member 66 is arranged in a position meeting a spacer roller 44 holding a clearance α between a developing roller 43 and the photoreceptor 1. The shape of the seal member at the cleaning blade end is formed so that a clearance between the seal member and the cleaning member edge is widened from the position at a fixed distance from the longitudinal end of the cleaning member to the image area X side. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention removes developer from the surface of an image carrier such as an electrophotographic photosensitive member or electrostatic recording dielectric in an image forming apparatus such as an electrophotographic method or an electrostatic recording method for forming an image on a recording medium. The present invention relates to a cleaning device that is used for the purpose. The present invention also relates to an image forming apparatus having the cleaning device. The present invention also relates to an image carrier and a process cartridge that has a developing device and a cleaning device as process means acting on the image carrier and is detachably attached to the main body of the image forming apparatus.

  For example, in a transfer type electrophotographic image forming apparatus, a transfer that transfers a toner image (developer image) formed on the surface of an electrophotographic photosensitive member as an image carrier onto a recording material (recording medium) such as paper. After the process, it is necessary to remove the toner that does not contribute to the transfer and remains on the surface of the photoreceptor. As a cleaning member for removing the toner, a cleaning blade made of an elastic material such as rubber has been widely put into practical use. When such a blade is used, a seal member is provided at the end of the blade to prevent the toner removed by the blade from leaking to the outside. A seal member has been proposed that can prevent toner leakage and removes the toner that comes into contact with the photoconductor and adheres to the photoconductor (Patent Document 1). Conventionally, in order to improve the lubricity of the contact portion between the blade and the photoreceptor, a lubricant coating liquid in which a lubricant powder containing a component such as carbon fluoride is dispersed in a liquid such as alcohol is used. It is known to apply a lubricant to the contact edge portion. In recent years, for reasons such as simplification of the manufacturing process, a configuration in which the coating agent is not applied to the contact edge portion of the blade is desired. In this case, the frictional force between the blade and the photoreceptor surface is increased. As a means for solving this problem, there has been proposed a photoreceptor in which the lubricity of the photoreceptor surface is remarkably improved with a small addition amount without impairing electrophotographic characteristics and durability (Patent Document 2).

JP-A-11-143326 JP 2007-199688 A

  As described above, there is a technique for improving the lubricity of the contact portion between the blade and the photoconductor. However, when the process speed at the time of image formation is increased with the improvement of product specifications, the frictional force between the blade and the surface of the photosensitive member is increased, and the possibility of blade turning and blade squealing increases. Therefore, further improvement in lubricity is required at the contact portion between the blade and the photoconductor. An object of the present invention is to provide a cleaning device, an image forming apparatus, and a process cartridge that can meet the above-mentioned demand. That is, the leakage of the developer at the blade end is prevented, and the lubricity of the contact portion between the blade and the image carrier at the blade end is improved while maintaining the effect of removing the developer attached to the image carrier. To prevent turning at the blade end.

  In order to achieve the above object, a typical configuration of a cleaning device according to the present invention is a rotatable image carrier on which a latent image is formed, and a developer is supplied to the image carrier to develop the latent image. A rotatable developer carrier, and a spacing member for contacting the image carrier and maintaining a predetermined distance between the image carrier and the developer carrier, and a recording medium A cleaning device for removing a developer from the surface of the image carrier used in an image forming apparatus for forming an image on the surface, for removing the developer in contact with the surface of the image carrier. A cleaning blade for storing the developer removed by the cleaning blade, and a seal member provided in the cleaning container, which is in contact with a longitudinal end portion of the cleaning blade. And a seal member that contacts the surface of the image carrier, and the seal member is provided at a position corresponding to the contact area of the spacing member on the surface of the image carrier, The gap (β) between the seal member and the tip of the cleaning blade is widened from a position at a predetermined distance from the end to the image area side of the image carrier.

  In order to achieve the above object, a typical configuration of the image forming apparatus according to the present invention includes a rotatable image carrier on which a latent image is formed, a developer supplied to the image carrier, and a latent image. A rotatable developer carrier for developing an image, a spacing member for contacting the image carrier and maintaining a predetermined distance between the image carrier and the developer carrier, and the image carrier A cleaning device for removing the developer from the surface of the body, and an image forming device for forming an image on a recording medium, the cleaning device being in contact with the surface of the image carrier A cleaning blade for removing the developer, a cleaning container for storing the developer removed by the cleaning blade, and a seal member provided in the cleaning container, the length of the cleaning blade And a seal member that contacts the surface of the image carrier, and the seal member is in a position corresponding to the contact area of the spacing member on the surface of the image carrier. The gap between the seal member and the tip of the cleaning blade is widened from a position that is provided at a predetermined distance from the end to the image area side of the image carrier. To do.

  In addition, a typical configuration of the process cartridge according to the present invention for achieving the above object is a process cartridge that is detachably attached to an apparatus main body of an image forming apparatus for forming an image on a recording medium. A rotatable image carrier on which a latent image is formed; a rotatable developer carrier for developing the latent image by supplying a developer to the image carrier; and abutting the image carrier An interval holding member for maintaining a predetermined interval between the image carrier and the developer carrier, and a cleaning device for removing the developer from the surface of the image carrier. A cleaning blade for coming into contact with the surface of the image carrier to remove the developer, a cleaning container for storing the developer removed by the cleaning blade, and the cleaning A seal member provided in a container, wherein the seal member is in contact with a longitudinal end portion of the cleaning blade and is in contact with a surface of the image carrier, and the seal member includes the image carrier. The seal member and the cleaning member are provided at a position corresponding to the contact area of the spacing member on the surface of the image bearing member, and from a position at a predetermined distance from the end to the image area side of the image carrier. It is characterized by a shape in which a gap with the tip of the blade is widened.

  Prevents developer leakage at the edge of the cleaning blade, maintains the effect of removing the developer adhering to the image carrier, and improves the lubricity of the contact portion between the blade and the image carrier at the blade edge Thus, turning up at the blade end can be prevented.

FIG. 2A is a schematic diagram illustrating a configuration of an image forming apparatus according to a first exemplary embodiment. FIG. 2B is a schematic diagram illustrating a positional relationship among a drum, a cleaning blade, an end seal member, and a spacer roller in a process cartridge. (A) is a perspective view of the cleaning device part, (b) is an exploded perspective view of the cleaning device. (A) thru | or (d) is explanatory drawing of the structure or shape of an edge part sealing member, respectively. (A) And (b) is explanatory drawing of the structure or shape of an edge part sealing member, respectively.

[Example 1]
(1) Description of Example of Image Forming Apparatus FIG. 1A is a schematic configuration diagram of an image forming apparatus (hereinafter referred to as an apparatus) 100 according to the first embodiment. The apparatus 100 is a process cartridge detachable laser beam printer using a transfer type electrophotographic process, and forms an image corresponding to image information input from the host apparatus 300 to the control circuit unit 200 on a recording material (recording medium) P. . The host device 300 is a computer image reader or the like. Inside the apparatus 100, a drum-type electrophotographic photosensitive member (hereinafter referred to as a drum) 1 is disposed as a rotatable image carrier on which a latent image is formed. Around the drum 1, a charging unit 2, an exposure unit 3, a developing unit 4, a transfer unit 5, and a cleaning unit 6 as process units acting on the drum 1 are sequentially arranged along the drum rotation direction. ing. The drum 1 is rotationally driven at a predetermined speed in the clockwise direction R1 of an arrow based on image forming operation sequence control. The charging means 2 is a contact charging roller in this embodiment. The roller 2 is disposed substantially in parallel with the drum 1 and in contact with the drum 1 with a predetermined pressing force. The roller 2 is rotated by the rotation of the drum 1. A predetermined charging bias is applied to the roller 2 at a predetermined control timing. As a result, the outer peripheral surface of the rotating drum 1 is uniformly charged to a predetermined polarity and potential. The exposure unit 3 is a unit that exposes an image to a drum surface that has been charged and forms an electrostatic latent image corresponding to the exposure image on the drum surface. In this embodiment, the exposure means 3 is a laser scanner, and outputs a laser beam L modulated in accordance with image information to scan and expose the drum surface. The electrostatic latent image formed on the drum surface is developed as a toner image (developer image) by the developing means 4. The developing means 4 is a magnetic one-component non-contact developing device in this embodiment. This device 4 will be described later. The toner image formed on the drum surface is sequentially transferred onto the recording material P in the transfer nip N that is a contact portion between the drum 1 and the transfer roller 5 as a transfer unit. The roller 5 is a conductive elastic roller made of EPDM sponge or the like, and is disposed substantially in parallel with the drum 1 and in contact with the drum 1 with a predetermined pressing force. The roller 5 rotates in the forward direction with respect to the rotation of the drum 1 at substantially the same speed as the rotation speed of the drum 1. The recording material P is stacked and stored in a recording material cassette 7 disposed in the lower part inside the apparatus 100. Then, the recording material P is separated and fed from the cassette 7 by driving the feeding roller 8 at a predetermined control timing. The fed recording material is conveyed to the nip N through the conveying path 9 in synchronization with the toner image on the drum reaching the nip N. While the recording material P is nipped and conveyed through the nip N, a predetermined transfer bias having a polarity opposite to the charging polarity of the toner is applied to the roller 5. The toner image on the drum surface is electrostatically transferred to the surface of the recording material P by the transfer electric field formed in the nip N. The recording material P passing through the nip N is separated from the drum surface, and is introduced into the fixing device 11 through the conveyance path 10. The toner image on the recording material is fixed as a fixed image on the surface of the recording material by being heated by a heat roller 11a provided in the apparatus 11 and by a pressure roller 11b. Then, the recording material P that has exited the apparatus 11 passes through the conveyance path 12 and is carried out onto the discharge tray 13 as an image formed product (print). Further, the transfer residual toner remaining on the drum surface after separation of the recording material is removed by the cleaning means 6. The cleaned drum 1 is repeatedly used for image formation. The cleaning means 6 is a blade cleaning device in this embodiment. This device 6 will be described later.

(2) Developing device 4
In the present embodiment, the developing device 4 is a non-contact developing device (jumping developing device) using magnetic one-component toner as a developer. The apparatus 4 includes a developing frame 48 that is partly a developing container 41. In the container 41, toner T is collected and stored. Further, a non-magnetic developing roller (development) as a developer carrying member for developing the latent image by supplying toner T to the drum 1 and rotatably disposed in the opening of the container 41 facing the drum 1. Sleeve) 43. The rollers 43 are arranged substantially in parallel with the drum 1. Further, as shown in FIG. 1B, spacer rollers 44 are provided as spacing members provided at both ends of the roller 43. Further, a non-rotating magnet 45 is provided as a magnetic field generating member disposed inside the roller 43. Further, a developing blade 46 having elasticity as a developer layer thickness regulating member disposed in contact with the outer surface of the roller 43, and a rotatable blade that stirs the toner T in the container 41 and conveys it to the roller 43 side. A member 47 is provided. The roller 44 is concentric with the roller 43 and has a predetermined larger diameter than the roller 43. The developing frame 48 is urged to move by a biasing member (spring member) in a direction in which the rollers 44 abut against the end-side surface of the drum 1. As a result, as shown in FIG. 1B, the distance between the drum 1 and the roller 43 is maintained at a predetermined distance (gap gap) α. The roller 43 carries the toner T on its outer surface by the magnetic force of the internal magnet 45 and is driven to rotate in the counterclockwise direction indicated by the arrow at a predetermined speed. The toner on the roller 43 is subjected to layer thickness regulation at the contact portion between the roller 43 and the blade 46. Thereby, a thin layer of toner is formed on the outer surface of the roller 43. Due to the friction between the roller 43 and the blade 46 at this time, the toner is charged with a predetermined polarity sufficient for development. With the subsequent rotation of the roller 43, the toner thin layer on the roller 43 is conveyed to the opposing space (development region) between the drum 1 and the roller 43. A predetermined alternating voltage is applied to the roller 43 as a developing bias. Due to an alternating electric field formed at the interval portion facing the drum 1, the toner flies at the opposite interval portion, and the electrostatic latent image on the drum surface becomes the toner. It is developed as an image (jumping development). In addition, the toner that is carried on the roller 43 without contributing to the development is carried into the container 41 by the subsequent rotation of the roller 43 and is mixed into the toner T in the container 41 and collected.

(3) Cleaning device 6
2A is a perspective view of the cleaning device 6 portion, and FIG. 2B is an exploded perspective view. This apparatus 6 is a blade cleaning system. In the following description, the longitudinal direction or the longitudinal direction is the direction of the axis of rotation of the drum 1 or a direction parallel thereto. The apparatus 6 includes a cleaning frame 69 that is partially a cleaning container (waste toner container) 61. The container 61 has an opening 62 facing the drum 1. The opening 62 extends along the length of the drum 1. A cleaning blade 63 is disposed downstream of the opening 62 in the drum rotation direction (downstream of the drum surface movement direction). The leading edge portion 63a of the free end of the blade 63 is brought into contact with the drum 1 to scrape off transfer residual toner (including other deposits such as paper dust) as deposits on the drum 1 into the container 61. It is the structure to store. The blade 63 is a blade-shaped elastic member extending in the longitudinal direction of the drum 1. This is widely used because of the advantages of downsizing the apparatus and eliminating the need for a drive source. The blade 63 is assembled to the container 61 so as to contact the drum 1 with the free end of the blade 63 facing the counter direction with respect to the rotation direction of the drum 1, that is, the upstream side in the surface movement direction of the drum 1. The front end portion (abutting edge portion) 63a on the drum 1 side surface of the blade 63 on the drum surface moving direction presses the drum 1, so that deposits such as residual toner remaining on the drum 1 after the transfer process. It is scraped off. The adhered matter scraped off is collected in a container 61 having an opening 62. The blade 63 is formed integrally with the holding member 64, and the blade 63 is assembled by fixing the holding member 64 to the container 61 with screws or the like. In the present embodiment, the material of the blade 63 is urethane rubber so as not to damage the drum 1. On the other hand, on the upstream side in the drum rotation direction (upstream side in the drum surface movement direction) of the opening 62 of the container 61, a flexible sheet member (rake sheet) 65 is disposed over the entire longitudinal direction of the opening 62. The member 65 is in contact with the drum surface below the leading edge portion 63a of the blade 63, and receives the adhering matter (cleaned waste toner) scraped off from the drum surface by the blade 63. It plays the role of not being guided out of the container. In this example, a sheet made of polyethylene terephthalate was used as the member 65. In this embodiment, the member 65 is bonded to the edge portion of the opening 62 on the upstream side in the drum rotation direction using a double-sided tape as an adhesive means. The length of the opening 62 is the same as or slightly shorter than the length of the blade 63. An auxiliary seal member 67 described later is located inside the opening 62. The end portion of the rake sheet 65 has a length corresponding to the inner end portion of the end seal members 66 and 66 described later.

(4) Process cartridge 50
In the apparatus 100 of the present embodiment, the drum 1 and the charging roller 2, the developing apparatus 4 and the cleaning apparatus 6 as process means acting on the drum 1 are detachably mounted on the apparatus main body 100A of the apparatus 100 in a lump. As a process cartridge 50 to be processed. The apparatus main body 100A is a part of the apparatus 100 excluding the cartridge 50. The cartridge 50 can be attached to and detached from the main body 100A by the user himself. Therefore, maintenance of the main body 100A can be easily performed. In the present embodiment, the drum unit 50A is configured by rotatably arranging the drum 1 and the charging roller 2 with respect to the frame 69 of the cleaning device 6. Further, the developing device 4 is a developing unit 50B separate from the drum unit 50A. The two units 50A and 50B are rotatably coupled to each other to form the cartridge 50. That is, as shown in FIG. 1B, the frame body 69 of the unit 50A and the frame body 48 of the unit 50B can be rotated by the shaft member (coupling member) 51 at one end side and the other end side in the longitudinal direction. The cartridge 50 is configured in combination with the above. Then, an urging member (spring member: not shown) is disposed between the frame body 69 and the frame body 48 so that the unit 50B is brought into contact with the drum 1 on the side of the unit 50A. The shaft member 51 is urged to rotate with respect to the unit 50A. As a result, as described above, the drum 1 and the roller 43 are held facing each other with a predetermined distance α. X is the image area (effective image forming area width) of the drum 1. This image region X is a drum region inside the inner end portion region of the roller 44 on one end side and the other end side of the developing roller 43. The cartridge 50 is detachably mounted on the mounting portion in the main body 100A in a predetermined manner. In a state where the cartridge 50 is mounted on the main body 100A in a predetermined manner, a drive input section (not shown) on the cartridge 50 side is mechanically coupled to a drive output section (not shown) on the main body 100A side. . As a result, the driving force is transmitted from the main body 100A side to the drum 1 to enable drum driving. Further, an electrical output section (not shown) on the cartridge 50 side is electrically coupled to an electrical output section (not shown) on the main body 100A side. Thereby, a predetermined bias can be applied to the roller 2 and the roller 43 from the main body 100A side. In this state, the apparatus 100 can perform an image forming operation. G1 is a drum gear disposed concentrically with the drum 1 and disposed on one end side of the drum 1. A driving force is transmitted to the gear G1 from the main body 100A side, and the drum 1 is rotationally driven in a predetermined direction and at a predetermined speed. G2 is a developing gear disposed concentrically with the roller 43 and disposed on one end side of the roller 43. The gear G2 meshes with the gear G1. As a result, the roller 43 is rotationally driven in a predetermined direction and at a predetermined speed in conjunction with the rotation of the drum 1. Further, the rotational force is transmitted from the gear G2 to the blade member 47 via a power transmission mechanism (not shown), and the member 47 is rotationally driven in a predetermined direction and at a predetermined speed. As the cartridge 50 is used for image formation, the stored developer is consumed. When the developer is consumed, it is necessary to replace the cartridge with a new one. Therefore, a means (not shown) for detecting the remaining amount of the developer is provided, and the control circuit unit 200 compares the detected remaining amount value with a preset threshold value for cartridge life warning or life warning. For cartridges for which the detected remaining value is less than the threshold, a cartridge life warning or life warning is displayed on the display unit (not shown). This prompts the user to prepare a cartridge for replacement, or prompts the user to replace the cartridge to maintain the quality of the output image. However, no means for detecting the remaining amount of developer need be provided.

(5) Seal configuration of the cleaning device 6 The cleaning device 6 has the following seal configuration in order to prevent waste toner collected in the container 61 from leaking out from both ends in the longitudinal direction of the blade 63. That is, in order to prevent waste toner from being discharged out of the container 61, elastic seal members (end seal members) 66 are disposed at both ends in the longitudinal direction of the opening 62, and this is applied to the drum 1. Make contact. The seal member 66 is a member that can prevent toner leakage from the end of the blade and remove the toner that contacts the drum 1 and adheres to the drum. FIGS. 3A and 3B are enlarged perspective views of the seal member 66 on one end side. Since the seal member on the other end only has a symmetrical relationship with the seal member on the one end side, description of the seal member on the other end side is omitted. The seal member 66 includes a longitudinal seal portion 66A that abuts the longitudinal end surface 63-1 of the blade 63 with the longitudinal seal surface 66-1, and a lateral seal surface 66-2 with respect to the tip surface 63-2 of the blade 63. A substantially L-shaped elastic member having a lateral seal portion 66B that is in contact with the elastic member 66 is used. And this sealing member 66 was fixed with the double-sided tape 68 as an adhesion | attachment means with respect to the end seal adhesion surface on the container 61 adjacent to the longitudinal direction edge part of the opening part 62. FIG. Further, an auxiliary seal member 67 such as polyurethane foam is provided on the back side of both end portions in the longitudinal direction of the blade 63 in order to prevent toner leakage from the container 61.

  In the developing device 4, the spacer rollers 44 disposed at both ends of the developing roller 43 are pressed against the surfaces of both ends of the drum 1 by a biasing member. Therefore, the toner adhering to the drum surface may be pressed between the drum 1 and the roller 44 and fixed to the roller contact area surface Y of the drum 1 (contact area: FIG. 1B). The adhered toner gradually increases until the cartridge 50 reaches the end of its life, and may be present as a lump of toner on the roller contact area surface Y of the drum 1. If there is such a lump of toner, the distance α between the drum 1 and the developing roller 43 may fluctuate, which may cause random image pitch unevenness in the direction perpendicular to the recording material conveyance direction. Therefore, in this embodiment, in order to remove the toner adhering to the roller contact area surface Y of the drum 1, the above-described seal member 66 for preventing the leakage of the toner removed from the drum 1 by the blade 63 is provided on the drum 1. It is attached at a position on the container 61 corresponding to the roller contact area surface Y. The seal member 66 is an elastic member that is compressed between the container 61 and the drum surface, and includes, for example, a foamed polyurethane layer as a toner leakage prevention portion and a polyfluorinated ethylene resin fiber as a toner removal portion. It is a composite member with a pile fabric layer such as velvet. The seal member 66 is attached to the container 61 with the pile fabric layer side facing outside. That is, the seal member 66 made of an elastic member is compressed between the container 61 of the cleaning device 6 and the drum 1 at a position corresponding to the roller contact area surface Y, and is reliably applied to the drum 1 surface. As a result, the pile fabric layer that is the toner removal portion of the seal member 66 can take in and remove the toner on the roller contact region surface Y. The width of the roller contact region surface Y is included in the width of the contact region between the seal member 66 and the drum 1 (= the width dimension L2 of the seal member 66). Thus, it is possible to prevent toner from adhering to the roller contact area surface Y of the drum 1 without increasing the number of parts.

  In the present embodiment, the stepped portion Z is provided on the lateral seal surface 66-2 of the seal member 66. When the sealing member 66 is attached to the container 61, the horizontal sealing surface 66-2 of the horizontal sealing portion 66B is attached to the tip surface 63-2 of the blade 63 so as to contact the blade 63. Then, a gap β is generated between the lateral seal surface 63-3 of the stepped portion Z and the tip surface 63-2 of the blade 63. Here, the waste toner cleaned by the blade 63 from the drum 1 during image formation adheres to the contact edge portion 63a of the blade 63 with the surface of the drum 1 and reduces the frictional force between the blade 63 and the surface of the drum 1. Works as a lubricant. Waste toner does not adhere to the contact edge portion 66a of the blade 63 at the contact portion between the tip surface 63-2 of the blade 63 and the lateral seal surface 66-2 of the seal member 66. By providing the stepped portion Z, a gap β is made between the lateral seal surface 66-3 of the stepped portion Z and the tip surface 66-2 of the blade 63. Then, at the contact edge portion 63a of the blade 63, the waste toner cleaned from the image region X on the surface of the drum 1 along with image formation is laterally attached to a portion where there is a gap β with the seal member 66. be able to. Accordingly, in the longitudinal direction of the contact edge portion 63a of the blade 63, the toner adheres to a wider area than before (sealing members 10cR and 10cL of Patent Document 1), thereby improving the slip property between the drum surface and the blade 63. be able to. As described above, the cleaning device 6 has an end seal shape that prevents the toner leakage at the end portion and the drum contamination at the spacer roller contact portion while improving the sliding property between the blade 63 and the drum surface.

(6) Effect on turning-up and toner leakage In this embodiment, a roller 44 having a width of the contact area surface Y with the drum 1 of 10 mm is used. Then, as shown in FIG. 3C, the length L2 of the lateral seal portion 66B in the seal member 66 is set to 10 mm. The seal member 66 is attached and disposed at a position on the container 61 corresponding to the roller contact area surface Y of the drum 1. As shown in FIG. 3B, the longitudinal seal surface 66-1 of the seal member 66 and the longitudinal end side surface 63-1 of the blade 63 are brought into contact with each other, and the lateral seal surface 66-2 and the blade are brought into contact with each other. The tip end surface 63-2 of 63 was made to contact. The length L3 of the horizontal seal surface 66-2 of the seal member 66 (position at a predetermined distance from the end of the blade 63 toward the image region X side of the drum 1) is 3.0, 2.5, 2.0, Shaking was performed at 1.5, 1.0, and 0.0 mm, respectively. The toner leakage and blade turn-up were evaluated for each length (distance) L3. Further, in a state where the drum 1 and the blade 63 are in contact with each other, the length of the stepped portion Z (a length β) is formed so that a gap β is formed between the lateral seal surface 66-3 of the stepped portion Z and the tip end surface 63-2 of the blade 63. Depth) L4 was 1 mm. Further, the lubricant is not applied to the contact edge portion 63a of the blade 63, and the lubricity of the surface of the photoreceptor is improved with the small addition amount described in Example 1 of Patent Document 2 as the drum 1 without applying a lubricant. A photoreceptor was used. The image forming process speed was 250 mm / sec. As the developer T, a magnetic one-component toner was used. Regarding curling, the presence of occurrence of curling and curling was confirmed when a certain number of sheets were passed in a high temperature and high humidity environment with a temperature of 30 ° C. and a humidity of 80% with a print rate of 1% as a condition of low waste toner. The results are shown in Table 1. In Table 1, the evaluation regarding blade squeal and blade turning is shown as follows. ○ ...... No turning, no blade squeal. Δ Blade squeal occurred. ×… turn over occurred. The toner leakage was confirmed by visual observation of the image sample and the drum 1 when a predetermined number of sheets were passed at a low temperature and low humidity environment temperature of 15 ° C. and humidity of 20%. Similarly, the results are shown in Table 1. In Table 1, the evaluation of the presence or absence of toner leakage is shown as follows. ○ No toner leakage. × Toner leakage occurred.

  As the length L3 of the lateral seal surface 66-2 of the seal member 66 is increased, the waste toner that has been cleaned from the drum along with the image formation at the longitudinal end portion of the abutting edge portion 63a of the blade 63 with the drum surface. The area that does not adhere increases. For this reason, a region having a high frictional force becomes large. In this example, when the length L3 of the lateral seal surface 66-2 was 2.5 mm or more, blade squeal occurred, and turning occurred when the length was 3.5 mm or more. That is, it was confirmed that when the distance L3 is 1.5 mm to 2.5 mm, it is effective for preventing toner leakage and blade turning. In this embodiment, when the length L3 of the lateral seal surface 66-2 is 1.0 mm or less, toner leakage occurs.

(7) Effect on Drum Dirt Next, the length L3 of the lateral seal surface 66-2 of the seal member 66 is 2.5 mm, and the length L2 of the lateral seal portion 66B is 7.5 mm. That is, as shown in FIG. 3D, the seal member 66 is cut at the step portion on the image area side of the drum 1, so that the drum 1 and the seal are larger than the width 10 mm of the roller contact area surface Y of the drum 1. The contact width of the member 66 was narrowed. In a low-temperature and low-humidity environment with a temperature of 15 ° C. and a humidity of 20%, a fixed number of sheets were passed under the same conditions as the above-described image forming conditions. Further, it was confirmed that the toner was fixed on the roller 44. In this example, when each of the above dimensions L2, L3, and L4 of the seal member 66 was set to the conditions shown in Table 2 below, good results were obtained with respect to drum dirt, toner leakage, and blade turning. .

  In this embodiment, a sealing member 66 having a shape as shown in FIG. That is, the length L4 is set to 4 mm, and when the drum 1 is brought into contact with the blade, the width L4 is gradually increased toward the image area side of the drum 1 between the horizontal seal surface 66-3 and the blade tip surface 63-2 in the horizontal seal portion 66B. A wedge-shaped gap was created. When the same evaluation as described above was performed, the same effect as in the case of the sealing member having the step Z in FIG. 3C with respect to turning over, toner leakage, and drum contamination was confirmed.

[Example 2]
In the present embodiment, in the cleaning device 6 used in the first embodiment, the lubricant coating liquid is applied to the entire longitudinal direction of the contact edge portion 63a of the blade 63. Using the same cartridge 50 as in Example 1, the following two shapes A and B were evaluated as the end seal member 66 of the blade 63. [Shape A]: A shape having a stepped portion Z like the seal member 66 shown in FIG. 3C, and L2 = 10 mm, L3 = 2.0 mm, and L4 = 1.0 mm. [Shape B]: A shape without a stepped portion like the seal member 66 shown in FIG. 4B, and L2 = 10 mm, L3 = 5.0 mm, and L4 = 0.0 mm. Evaluation similar to Example 1 was performed on the cleaning device using the sealing member of shape A and the cleaning device using the sealing member of shape B. As a result of the evaluation, good results could be obtained in any shape with respect to toner leakage, drum dirt, and blade turning.

  Next, the blade turning was evaluated under more severe conditions. The image forming conditions were the same as in Example 1. In a high-temperature and high-humidity environment at 35 ° C. and 85%, the presence or absence of turning-up of the blade was confirmed when a fixed number of sheets were passed at a printing rate of 0% (solid white printing). . As a result, in the cleaning device using the shape B seal member, the blade turned up from the end. Even when the lubricant coating liquid is applied, if the length L3 of the lateral seal surface 66-2 that is in contact with the blade tip surface 63-2 is large, the region with a high frictional force becomes large. This is because the region where the waste toner cleaned from the drum 1 does not adhere to the image forming portion becomes larger at the longitudinal end portion of the contact edge portion 63a with the drum surface of the blade 63. In this embodiment, even when the lubricant coating liquid is applied, the cleaning device using the shape A seal member is more slippery with the drum surface at the blade end than the cleaning device using the shape B seal member. Can be improved. As a result, it was confirmed that it was effective for turning over the blade.

  As described above, even when the lubricant coating liquid is applied to the contact edge portion 63a of the blade 63, the sealing member having the stepped portion Z in the lateral seal portion 66B has a good result regarding drum dirt and toner leakage. Could get. In addition, the sliding property with the drum increased at the blade end as compared with the conventional shape, and it was confirmed that the blade was turned up effectively.

[Others]
1) Embodiments 1 and 2 have described image forming apparatuses that perform single-color image formation, but the present invention is not limited to these embodiments, and color image forming apparatuses that perform image formation of a plurality of colors are also included. Applicable. 2) The present invention is not limited to an electrophotographic image forming apparatus using a magnetic one-component non-contact developing method, but can also be applied to an image forming apparatus using an electrostatic recording method using a magnetic one-component non-contact developing method. In the case of this image forming apparatus, an electrostatic recording dielectric is used as an image carrier and is charged uniformly by a charging means. Then, an electrostatic latent image is formed by selectively discharging the charged surface in accordance with an image information signal using a static elimination needle array or an electron gun unit as a latent image forming means. 3) The developing device 4 may be a non-magnetic one-component non-contact developing method, a two-component non-contact developing method or a two-component contact developing method. 4) The electrostatic latent image may be developed by reversal development or regular development.

  100..Image forming apparatus, 1 .... Image carrier, 43..Developer carrier, 44..Interval holding member, .alpha..Space between image carrier and developer carrier, T..Development Agent, 6 ... Cleaning device 61 ... Cleaning frame 63 ... Cleaning blade 66 ... Sealing member P ... Recording medium X ... Image area of image carrier 1 Y ... Image carrier Contact area of the spacing member on the surface of L3, L3... Predetermined distance

Claims (9)

  A rotatable image carrier on which a latent image is formed, a rotatable developer carrier for supplying a developer to the image carrier to develop the latent image, and an image in contact with the image carrier An interval holding member for maintaining an interval between the carrier and the developer carrier at a predetermined interval, and used in an image forming apparatus for forming an image on a recording medium, from the surface of the image carrier. A cleaning device for removing the developer, the cleaning blade for contacting the surface of the image carrier to remove the developer, and the cleaning container for storing the developer removed by the cleaning blade And a seal member provided in the cleaning container, wherein the seal member is in contact with a longitudinal end of the cleaning blade and is in contact with the surface of the image carrier. The material is provided at a position corresponding to the contact area of the spacing member on the surface of the image carrier, and from a position at a predetermined distance from the end to the image area side of the image carrier. A cleaning device having a shape in which a gap between the seal member and the tip of the cleaning blade is widened.   The seal member is provided with a step portion so that a gap between the seal member and the tip of the cleaning blade is widened from a position at a predetermined distance from the end portion to the image area side of the image carrier. The cleaning device according to claim 1, wherein the cleaning device has a shape.   The cleaning device according to claim 1, wherein a width of the contact area is included in a width of a contact area between the seal member and the image carrier.   A rotatable image carrier on which a latent image is formed, a rotatable developer carrier for supplying a developer to the image carrier to develop the latent image, and an image in contact with the image carrier An interval holding member for maintaining a predetermined interval between the carrier and the developer carrier, and a cleaning device for removing the developer from the surface of the image carrier, and an image is recorded on the recording medium. An image forming apparatus for forming the image forming apparatus, wherein the cleaning device contacts a surface of the image carrier and removes the developer, and stores the developer removed by the cleaning blade. A cleaning member provided on the cleaning container, the seal member being in contact with a longitudinal end of the cleaning blade and being in contact with the surface of the image carrier. The seal member is provided at a position corresponding to the contact region of the spacing member on the surface of the image carrier, and a predetermined distance is opened from the end portion to the image region side of the image carrier. An image forming apparatus having a shape in which a gap between the sealing member and the tip of the cleaning blade is widened from a predetermined position.   The seal member is provided with a step portion so that a gap between the seal member and the tip of the cleaning blade is widened from a position at a predetermined distance from the end portion to the image area side of the image carrier. The image forming apparatus according to claim 4, wherein the image forming apparatus has a shape.   6. The image forming apparatus according to claim 4, wherein the width of the contact area is included in the width of the contact area between the seal member and the image carrier.   A process cartridge that is detachably attached to an apparatus main body of an image forming apparatus for forming an image on a recording medium, and a rotatable image carrier on which a latent image is formed, and a developer on the image carrier A rotatable developer carrier for supplying and developing the latent image, and a spacing member for contacting the image carrier and maintaining a predetermined distance between the image carrier and the developer carrier; A cleaning device for removing the developer from the surface of the image carrier, the cleaning device contacting the surface of the image carrier and removing the developer, and A cleaning container for storing the developer removed by the cleaning blade, and a seal member provided on the cleaning container, which is in contact with a longitudinal end portion of the cleaning blade And a seal member that contacts the surface of the image carrier, and the seal member is provided at a position corresponding to the contact region of the spacing member on the surface of the image carrier, A process cartridge having a shape in which a gap between the seal member and the tip of the cleaning blade is widened from a position at a predetermined distance from an end to an image area side of the image carrier.   The seal member is provided with a step portion so that a gap between the seal member and the tip of the cleaning blade is widened from a position at a predetermined distance from the end portion to the image area side of the image carrier. The process cartridge according to claim 9, which has a shape.   9. The process cartridge according to claim 7, wherein the width of the contact area is included in the width of the contact area between the seal member and the image carrier.