JP2019074596A - Cleaning device and image forming apparatus - Google Patents

Abstract

To provide a cleaning device that can reduce wear of a blade, and an image forming apparatus.SOLUTION: A cleaning device 1 comprises a cleaning blade 20 and an attachment attaching/detaching member 24. The cleaning blade 20 presses a cleaning target rotating member having a developer attached to its surface to clean the cleaning target rotating member. The attachment attaching/detaching member 24 is provided on the upstream side in a rotation direction DR1 of the cleaning target rotating member with respect to a contact part S at which the cleaning blade 20 and the cleaning target rotating member are in contact with each other. The attachment attaching/detaching member 24 is configured to collect a developer scraped off from the cleaning target rotating member by the cleaning blade 20 and scattering, and supply the collected developer to the contact part S.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a cleaning device and an image forming apparatus.

  With regard to the conventional image forming apparatus, for example, in Japanese Patent Application Laid-Open No. 2007-101989, when the cleaner blade or the seal is separated from the surface of the carrier, the toner cloud is prevented from spouting from the cleaner housing to prevent the toner Patent Document 1 discloses an image forming apparatus capable of high-speed processing without contamination in the apparatus main body by preventing leakage of the light.

  The image forming apparatus disclosed in Patent Document 1 includes a cleaner blade, a seal member, a seal support member, and a facing member. The cleaner blade and the seal member come in contact with the surface of the intermediate transfer belt to scrape, remove and collect residual toner on the surface of the intermediate transfer belt. A seal support member supporting the conductive seal member faces the facing member. A vent hole is opened in the seal support member.

  In the above-described image forming apparatus, by supplying a positive voltage higher than that of the intermediate transfer belt to the facing member, an electric field is generated to cause the facing member to collect toner of negative potential in the cleaner housing through the vent. .

  Besides, as a document disclosing a conventional image forming apparatus, there is JP-A-2011-164470 (Patent Document 2).

Unexamined-Japanese-Patent No. 2007-101989 JP 2011-164470 A

  As disclosed in the above-mentioned Patent Document 1, there is known a configuration in which a blade is used to scrape off residual toner on the surface of a member to be cleaned such as an intermediate transfer belt to clean the member to be cleaned. In such a configuration, since the blade is in contact with the member to be cleaned at the time of cleaning, the edge portion of the blade is worn away. Abrasion of the edge portion of the blade may reduce the cleaning performance and cause a cleaning failure.

  An object of the present invention is to provide a cleaning device and an image forming apparatus capable of suppressing blade wear.

  A cleaning device according to the present invention comprises a cleaning blade and a deposit desorbing member. The cleaning blade cleans the cleaning target rotating member by pressing the cleaning target rotating member to which the developer adheres on the surface. The deposit desorbing member is provided on the upstream side of the cleaning target rotating member in the rotational direction with respect to the contact portion with which the cleaning blade and the cleaning target rotating member are in contact. The attached matter removing member is configured to collect the developer scraped off and scattered from the cleaning target rotating member by the cleaning blade and to supply the collected developer to the contact portion.

According to the above-described cleaning device, wear of the blade portion can be suppressed.
In the above-described cleaning device, the deposit desorbing member is conductive and grounded. Thereby, wear of the blade portion can be suppressed.

  The above cleaning device further comprises a housing and a seal member. The housing contains a cleaning blade and a deposit desorbing member. The seal member seals the developer which is scattered so as not to leak to the outside of the housing. The sealing member is provided in contact with the surface of the cleaning target rotating member. The deposit desorbing member is provided on the seal member in the interior of the housing. Thereby, the cleaning device can be made compact.

  In the above cleaning device, the cleaning blade has a cleaning surface facing upward. The cleaning surface includes a contact portion. The deposit desorbing member is provided substantially immediately above the cleaning surface. Thereby, a fixed amount of stationary layers can be stably held.

  In the above-described cleaning device, the deposit desorbing member includes a protrusion that protrudes toward the cleaning surface and has a corner at the protruding tip. The corner is provided approximately directly above the cleaning surface. Thereby, a fixed quantity of stationary layers can be held more stably.

  In the above-mentioned cleaning device, the deposit desorbing member has a V-like shape forming a protrusion. Thereby, the collection amount of the toner and the external additive can be increased.

  In the above-described cleaning device, the cleaning blade has a cleaning surface facing downward. The cleaning surface includes a contact portion. The deposit desorbing member has an inclined surface extending obliquely downward toward the cleaning member to be cleaned. Thereby, a fixed quantity of stationary layers can be held more stably.

  In the above-described cleaning device, the developer contains toner. The attachment desorbing member collects the toner which is scraped off and scattered from the cleaning target rotating member by the cleaning blade by applying a bias of the reverse polarity to the toner. Thus, the toner collection efficiency can be improved at the time of image formation.

  In the above-mentioned cleaning device, the developer contains an external additive. The attachment desorbing member collects the external additive scraped off and scattered from the cleaning target rotating member by the cleaning blade when a bias having a reverse polarity to the external additive is applied. Thereby, at the time of non-image formation, the collection efficiency of the external additive can be improved.

  In the above-described cleaning device, the developer contains toner. The deposit desorbing member desorbs the toner collected by the deposit desorbing member when a bias having the same polarity as the toner is applied. Thereby, a fixed amount of stationary layers can be stably held.

  In the above-mentioned cleaning device, the developer contains an external additive. The deposit desorbing member desorbs the external additive collected by the deposit desorbing member when a bias having the same polarity as the external additive is applied. Thereby, a fixed amount of stationary layers can be stably held.

  In the above-described cleaning device, the deposit desorbing member is shaken to release the collected developer. Thereby, a fixed amount of stationary layers can be stably held.

  The above-described cleaning device further includes a crosslink preventing member that prevents crosslink of the toner. The deposit desorbing member is pressed by the crosslink preventing member to release the collected developer. Thereby, a fixed amount of stationary layers can be stably held.

  In the above-described cleaning device, the deposit desorbing member desorbs the collected developer when an AC bias is applied. Thereby, a fixed amount of stationary layers can be stably held.

  An image forming apparatus according to the present invention includes the cleaning device according to any one of the above aspects, and a developing unit for applying a developer to the cleaning target rotating member. Thereby, the downtime of the image forming apparatus can be suppressed.

  The above-described image forming apparatus further includes an information acquisition unit and a control unit. The information acquisition unit acquires the amount of rotation of the cleaning target rotating member and the coverage of the recording medium on which an image is formed. The control unit controls the deposit desorbing member to release the collected developer according to the amount of rotation and the coverage acquired by the information acquiring unit. Thereby, a fixed amount of stationary layers can be stably held.

  In the above-described image forming apparatus, the control unit controls the developing unit to apply the developer to the cleaning target rotating member in accordance with the amount of rotation and the coverage acquired by the information acquiring unit. Thereby, a fixed amount of stationary layers can be stably held.

  In the above-described image forming apparatus, the recording medium has a plurality of divided areas aligned in a direction orthogonal to the conveyance direction of the recording medium, and the information acquisition unit acquires coverage for each of the plurality of divided areas. Thereby, a fixed amount of stationary layers can be stably held.

  According to the application of the present invention, it is possible to realize a cleaning device and an image forming apparatus capable of suppressing blade wear.

1 shows a schematic cross-sectional view of a main part of an electrophotographic process of an image forming apparatus including a cleaning device according to Embodiment 1. FIG. FIG. 2 is a schematic cross-sectional view of the vicinity of the cleaning device according to the first embodiment. It is an enlarged view of area | region III shown in FIG. FIG. 1 is a block diagram showing the configuration of an image forming apparatus. FIG. 10 is a schematic cross-sectional view of the vicinity of the cleaning device according to the second embodiment. FIG. 14 is a schematic cross-sectional view of the vicinity of the cleaning device according to the third embodiment. FIG. 14 is a schematic cross-sectional view of the vicinity of the cleaning device according to the fourth embodiment. It is a figure showing an example of control for holding a fixed amount of stationary layers stably. It is a table | surface which shows the measurement result of the wear width of a braid | blade part.

  Hereinafter, the cleaning device 1 and the image forming apparatus 100 in each embodiment will be described based on the drawings. In the embodiments described below, the same or substantially the same configurations are denoted by the same reference numerals, and redundant description will not be repeated. Each configuration of the embodiments described below may be selectively combined as appropriate.

Embodiment 1
[Image forming apparatus 100]
FIG. 1 shows a schematic cross-sectional view of a main part of an electrophotographic process of an image forming apparatus 100 including the cleaning device 1 according to the first embodiment. Image forming apparatus 100 according to the first embodiment is a full color tandem type electrophotographic system. The image forming apparatus 100 transfers a toner image formed on the photosensitive member 10 to be described later to a recording medium T such as a sheet by an electrophotographic image forming process, fixes the toner image on the recording medium T, and forms an image. Do.

  The image forming apparatus 100 includes a primary transfer unit 50, a transfer belt 5, a support roller 12, and a cleaning device 1. The primary transfer unit 50 includes a photosensitive member 10, a charging unit 2, an exposure unit 3, a developing unit 4, and a primary transfer roller 6. The photosensitive member 10 rotates in a rotational direction DR1 shown in FIG. Around the photosensitive member 10, a charging unit 2, an exposure unit 3, a developing unit 4, a primary transfer roller 6, and a cleaning device 1 are disposed in order along the rotational direction DR1 of the photosensitive member 10.

  The charging unit 2 uniformly charges the surface of the photosensitive member 10. The exposure unit 3 exposes a portion of the surface of the photosensitive member 10 on which an image is to be formed, and forms an electrostatic latent image on the surface of the photosensitive member 10. The developing unit 4 applies a developer containing toner, an external additive, and the like to the surface of the photosensitive member 10 to visualize the electrostatic latent image on the photosensitive member 10. Thus, a toner image corresponding to the electrostatic latent image is formed on the surface of the photosensitive member 10.

  The toner images of the respective colors formed on the respective photosensitive members 10 are overlapped and transferred onto the transfer belt 5 by the action of the electric field by the respective primary transfer rollers 6 (primary transfer). Transfer residual toner which has not been transferred to the transfer belt 5 remains on the photosensitive member 10. The cleaning device 1 cleans the transfer residual toner on the photosensitive member 10. Details of the cleaning device 1 will be described later.

  The transfer belt 5 is supported in a state where a constant belt tension is given by a plurality of support rollers 12 arranged in parallel. One of the plurality of support rollers 12 is connected to a motor or the like (not shown) and is driven to rotate. The transfer belt 5 rotates counterclockwise.

  The image forming apparatus 100 further includes a secondary transfer roller 8, a fixing unit 11, and a cleaning unit 9. The secondary transfer roller 8 is provided downstream of the primary transfer unit 50 in the rotational direction of the transfer belt 5. The secondary transfer roller 8 transfers a plurality of color toner images superimposed and transferred onto the transfer belt 5 to the recording medium T by the action of an electric field (secondary transfer).

  The fixing unit 11 heats and presses the toner image transferred onto the recording medium T to fix the toner image on the recording medium T. The cleaning unit 9 cleans the transfer residual toner remaining on the transfer belt 5 without being transferred to the recording medium T.

<Cleaning device 1>
FIG. 2 is a schematic cross-sectional view of the vicinity of the cleaning device 1 according to the first embodiment. Arrows illustrated in FIG. 2 indicate the downward direction DR3 and the upward direction DR2. The downward direction DR3 is the direction in which gravity acts, and is the downward direction in FIG. The upward direction DR2 is the direction opposite to the direction in which the gravity acts, and is the upward direction in FIG. The cleaning device 1 will be described with reference to FIG.

  The cleaning device 1 includes a cleaning blade 20, a housing 22, a transport screw 23, and a seal member 25. The cleaning blade 20 cleans the cleaning target rotating member by scraping the developer on the cleaning target rotating member by pressing the cleaning target rotating member having the developer attached to the surface thereof. In the first embodiment, the member to be cleaned is the photosensitive member 10. The cleaning blade 20 is disposed to face the photosensitive member 10.

  The cleaning blade 20 is housed in a housing 22. The transfer residual toner scraped off by the cleaning blade 20 scatters in the housing 22. The seal member 25 seals between the photosensitive member 10 and the housing 22 so that the scattered transfer residual toner does not leak to the outside of the housing 22 and contaminate the periphery of the photosensitive member 10. The seal member 25 is provided in contact with the surface of the photosensitive member 10. By providing the sealing member 25, the inside of the housing 22 is sealed. The transfer residual toner accumulated in the housing 22 is conveyed by the conveyance screw 23 and accommodated in a waste toner accommodation box (not shown).

(Cleaning blade 20)
The cleaning blade 20 includes a blade 20a and a support member 20b. The blade 20a and the support member 20b are bonded by an adhesive. As the adhesive, a thermoplastic hot melt adhesive is used. It is also possible to use a double-sided tape to connect the blade 20a and the support member 20b.

  As another configuration of the cleaning blade 20, the cleaning blade 20 may be configured using a manufacturing method in which the blade 20a is attached to the support member 20b by integral molding with a mold when the blade 20a is molded. In this case, the cleaning blade 20 is configured without adhesive.

  The blade 20a is an elastic body. The material of the blade 20a is, for example, a urethane rubber that is excellent in abrasion resistance and ozone resistance. The thickness of the blade 20a is preferably about 0.5 [mm] or more and 2.0 [mm] or less.

  The blade 20a has a strip-like shape extending in the depth direction (long side direction) in the drawing of FIG. The blade 20 a extends in the long side direction beyond the area (image forming area) on the photosensitive member 10 on which the toner image is formed.

  The length in the short side direction of the blade 20a is preferably 5 mm or more and 12 mm or less, though it depends on the method of manufacturing the blade 20a, but may be longer than 12 mm. In the case of the blade 20a molded with a mold, the thickness of the blade 20a and the length in the short side direction of the blade 20a are further shortened (thickness: less than 0.5 mm, length in the short side direction: 5 mm) It is also possible to

  The blade 20a has an edge 20d and a cleaning surface 20c. The edge portion 20d is an end edge portion of the blade 20a in the upward direction DR2. The cleaning surface 20c faces upward. The cleaning surface 20c is an end surface of the blade 20a in the upward direction DR2. The cleaning surface 20 c is inclined obliquely downward toward the photosensitive member 10.

  When the blade 20 a is pressed by the photosensitive member 10, the contact portion S is formed at a portion where the edge portion 20 d and the photosensitive member 10 contact. The contact portion S is included in the cleaning surface 20c.

  When the edge portion 20 d is pressed by the photosensitive member 10, the edge portion 20 d elastically deforms along the surface of the rotating photosensitive member 10. The transfer residual toner after primary transfer conveyed from the upstream side of the rotational direction DR1 with respect to the contact portion S collides with the edge portion 20d. As a result, the transfer residual toner is scraped off by the edge portion 20 d and separated from the photosensitive member 10. The transfer residual toner in the area other than the image forming area of the photosensitive member 10 is also scraped off by the edge portion 20 d and peeled off from the photosensitive member 10.

  The blade 20a is supported by a plate-like support member 20b. The material of the support member 20b is, for example, a steel plate such as SECC. The support member 20 b suppresses deformation of the cleaning blade 20 caused by pressure and external force applied to the blade 20 a. In order to ensure the strength of the cleaning blade 20 that the edge straightness of the cleaning blade 20 can satisfy the required specifications, it is preferable to set the thickness of the support member 20 b to 1.6 mm or more and 2.0 mm or less. .

  The distance between the blade 20 a and the photosensitive member 10 is defined by the installation position and installation angle of the support member 20 b on the housing 22. The amount of deflection of the blade 20 a is defined by the definition of the distance between the blade 20 a and the photosensitive member 10. The deflection amount of the blade 20a defines the force with which the blade 20a presses the photosensitive member 10.

(Abrasion reduction effect by the stationary layer L)
On the upstream side (on the cleaning surface 20c) of the contact portion S in the rotational direction DR1 (on the cleaning surface 20c), a stationary layer L composed of toner scraped off by the blade 20a and an external additive is formed. By forming the stationary layer L, the wear of the blade 20a is reduced. The reason will be described below.

  FIG. 3 is an enlarged view of a region III shown in FIG. Part of the transfer residual toner scraped off by the blade 20a accumulates on the cleaning surface 20c. The stationary layer L is formed by the accumulated transfer residual toner. In the stationary layer L, the toner is convective by the force received from the surface of the moving photoreceptor 10. The convection of the toner causes the external additive to separate from the toner. As a result, in the stationary layer L, large-diameter toner, medium-sized external additive, and small-sized external additive are present.

  In the stationary layer L, particle diameter sorting is performed by convection of the toner and the external additive. Specifically, the smaller the particle diameter, the closer the photosensitive member 10 is to be present. That is, the toner with the large diameter is present at a distance from the photosensitive member 10, and the external additive with the small diameter tends to be present at a position near the photosensitive member 10.

  When the stationary layer L is at least a certain amount, the small-diameter external additive present at a position close to the photosensitive member 10 in the stationary layer L is pushed by the other particles in the stationary layer L to move toward the photosensitive member 10 The cleaning surface 20c, which extends obliquely downward, descends, and is supplied to the contact portion S between the edge portion 20d and the photosensitive member 10. The small diameter external additive intervenes in the contact portion S. As a result, the small-diameter external additive plays the role of a roller, so the frictional force generated between the edge portion 20 d and the photosensitive member 10 is reduced. Therefore, wear of the edge portion 20d of the blade 20a can be suppressed.

(Decrease of stationary layer L)
As the photosensitive member 10 rotates, a small diameter external additive interposed in the contact portion S slips through the contact portion S. When the stationary layer L is at least a certain amount, the small-diameter external additive present at a position close to the photosensitive member 10 is pushed by the other particles in the stationary layer L and supplied to the contact portion S. Therefore, when there is a fixed amount of the stationary layer L, the contact portion S is often in a state in which an external additive with a small diameter intervenes.

  However, the toner and the external additive in the stationary layer L have an electrical repulsive force generated between the photosensitive member 10 and the reverse charge (the photosensitive member 10 is negatively charged), and between the blade 20 a and the photosensitive member 10. The vibration of the blade 20 a due to the contact causes it to splash on the cleaning surface 20 c upward (in the direction of the white arrow in FIG. 3) and scatter in the housing 22. Most of the scattered toner and external additive are discarded as waste toner without contributing to the formation of the stationary layer L. Therefore, as the photosensitive member 10 rotates, the stationary layer L becomes smaller. When the stationary layer L falls below a predetermined amount, the small diameter external additive is not supplied to the contact portion S. Therefore, in order to suppress the wear of the edge portion 20d, it is necessary to stably hold a certain amount of the stationary layer L.

(Attachment desorption member 24)
As shown in FIG. 2, the cleaning device 1 further includes a deposit desorbing member 24. The deposit desorbing member 24 is housed inside the housing 22. The attachment desorbing member 24 is provided on the upstream side of the contact portion S in the rotational direction DR1 of the photosensitive member 10. The deposit desorbing member 24 is provided substantially immediately above the cleaning surface 20c. The deposit desorbing member 24 is scraped from the photosensitive member 10 by the blade 20a, and the toner and the external additive scattered into the inside of the housing 22 are absorbed by electric force on the surface of the deposit desorbing member 24 and collected.

  The deposit desorbing member 24 has conductivity and is grounded. The deposit desorbing member 24 is provided so as to have a potential difference with the scattered toner and the external additive. The deposit desorbing member 24 collects scattering toner when a DC bias (DC bias, the same applies hereinafter) having a reverse polarity to that of the toner is applied.

  In the image forming process using an organic photosensitive member, mainly, negatively charged toner is used. At the time of image formation, the developing unit 4 supplies toner to the photosensitive member 10. The collection efficiency of the toner can be improved by applying a positive DC bias to the deposit desorbing member 24 at the timing when the toner developed on the photosensitive member 10 rushes into the blade 20a at the time of image formation.

  On the other hand, the extraneous matter desorbing member 24 can also capture the scattering external additive by applying a DC bias of the reverse polarity to the external additive. Some external additives are opposite in polarity to the toner, that is, positively charged. Therefore, the external additive is attracted onto the negatively charged photoreceptor 10. At the time of non-image formation such as an interval between printing, toner is not supplied from the developing unit 4 to the photosensitive member 10. For this reason, most of those attracted to the photosensitive member 10 at the time of non-image formation are external additives that are positively charged. For this reason, the collection efficiency of the external additive can be improved by applying a negative DC bias to the deposit desorption member 24 at the time of non-image formation.

  The toner and the external additive collected by the deposit desorbing member 24 fall by gravity from the deposit desorbing member 24 in the downward direction DR3 when a certain amount is exceeded. Since the attached matter removing member 24 is provided substantially immediately above the cleaning surface 20c, the toner and the external additive reliably drop onto the cleaning surface 20c. The deposit desorbing member 24 supplies the collected toner and the external additive onto the cleaning surface 20c. Thereby, the stationary layer L is formed on the cleaning surface 20c. When the stationary layer L is already formed, the stationary layer L becomes large. Therefore, a fixed amount of stationary layer L can be stably held. By holding a fixed amount of stationary layer L, the small diameter external additive present at a position close to the photosensitive member 10 is pushed by other particles in the stationary layer L and supplied to the contact portion S. become.

  As described above, by configuring the deposit desorbing member 24 so as to supply the collected toner and the external additive to the contact portion S, it is possible to stably hold a fixed amount of the stationary layer L. As a result, the contact portion S is in a state in which a small diameter external additive intervenes, and wear of the blade 20a can be suppressed. Therefore, the maintenance frequency of the blade 20 a can be suppressed, and the downtime (stop time) of the image forming apparatus 100 by the cleaning device 1 can be suppressed.

<Control unit 30>
FIG. 4 is a block diagram showing the configuration of the image forming apparatus 100. As shown in FIG. The image forming apparatus 100 further includes an information acquisition unit 31 and a control unit 30. The information acquisition unit 31 includes a rotation amount acquisition unit 31 a and a coverage acquisition unit 31 b. The rotation amount acquisition unit 31 a acquires the rotation amount of the photosensitive member 10. The amount of rotation of the photosensitive member 10 is the product of the length of the outer periphery of the photosensitive member 10 and the number of rotations of the photosensitive member 10. The coverage acquisition unit 31b acquires the coverage of the recording medium T on which an image is formed. The coverage acquisition unit 31b acquires the average coverage of the recording medium T on which a plurality of images are formed. The coverage of the recording medium T is the black-and-white ratio of the recording medium T on which the image is formed (the ratio of the portion of the recording medium T on which the toner image is formed).

  The amount of rotation and the coverage of the photosensitive member 10 are highly correlated with the consumption of the stationary layer L. As the amount of rotation of the photosensitive member 10 increases (as the photosensitive member 10 rotates), the external additive passes through the contact portion S, and the stationary layer L becomes smaller. When the recording medium T with low coverage is image-formed for a long time, the amount of toner supplied to the photosensitive member 10 decreases, so the amount of toner scraped off from the photosensitive member 10 decreases and the stationary layer L becomes smaller .

  When the condition that the stationary layer L becomes a predetermined amount or less (the rotation amount of the photosensitive member 10 after image formation is a predetermined value or more and the average coverage of the recording medium T on which the image is formed is a predetermined value or less) The control unit 30 controls the developing unit 4 to apply the developer containing the toner and the external additive to the photosensitive member 10.

  Specifically, the control unit 30 controls the developing unit 4 so that a belt-like toner (toner band) is formed on the photosensitive member 10 at the time of non-image formation. The blade 20a scrapes the toner band formed on the photosensitive member 10, whereby a part of the toner band can be supplied onto the cleaning surface 20c. Thereby, the stationary layer L of a fixed amount can be hold | maintained. A part of the toner band that has been splashed up by the blade 20 a is collected by the deposit desorbing member 24.

  A band-shaped toner image (vertical band) extending in the transport direction of the recording medium T may be continuously printed on the recording medium T in the print production area. In this case, even if the coverage of the recording medium T as a whole is large, when the area division is viewed, a small portion of the coverage occurs. Therefore, the toner can not be scraped off in the portion of the recording medium T without the vertical band, and a portion in which the stationary layer L is small occurs on the cleaning surface 20c. Thereby, the wear of the blade 20a is partially increased.

  In view of such a case, it is preferable that the coverage acquiring unit 31b divides the area of the recording medium T and acquires the coverage instead of acquiring the coverage of the entire recording medium T. Specifically, the recording medium T is divided into a plurality of areas aligned in the direction orthogonal to the conveyance direction of the recording medium T (the width direction of the recording medium T), and the coverage acquiring unit 31b calculates the coverage for each divided area. get. As a result, even when an image is formed on a recording medium T having a small coverage when viewed in divided areas, the wear of the blade 20a can be suppressed.

Second Embodiment
FIG. 5 is a schematic cross-sectional view of the vicinity of the cleaning device 1 according to the second embodiment. The deposit desorbing member 24 according to the second embodiment has a V shape. The deposit attachment / detachment member 24 has a first inclined portion 24 a, a second inclined portion 24 b, and a protrusion 26. The protrusion 26 has a V-like shape. The first inclined portion 24 a extends obliquely upward from the protrusion 26. The second inclined portion 24 b extends obliquely upward from the protrusion 26. The second inclined portion 24 b extends from the protrusion 26 in a direction away from the first inclined portion 24 a.

  By providing the first inclined portion 24a and the second inclined portion 24b, the surface area of the attached matter desorbing member 24 for collecting the toner and the external additive is increased, so the collection amount of the toner and the external additive Can be increased.

  The protrusion 26 protrudes toward the cleaning surface 20c. The protrusion 26 faces downward. The protrusion 26 has a corner 26 a at the tip of the protrusion. The corner 26a is provided substantially immediately above the cleaning surface 20c.

  By providing the corner portion 26 a, the toner and the external additive collected by the first inclined portion 24 a and the second inclined portion 24 b are easily collected at the corner portion 26 a. As a result, the collected toner and the external additive are easily dropped onto the cleaning surface 20c, so that the fixed layer L can be stably held.

  Furthermore, the deposit desorbing member 24 according to the second embodiment is provided to overlap the seal member 25 inside the housing 22. The first inclined portion 24 a is in contact with the seal member 25. Thereby, the cleaning device 1 can be made compact.

Third Embodiment
FIG. 6 is a schematic cross-sectional view of the vicinity of the cleaning device 1 according to the third embodiment. The blade 20a according to the third embodiment has a cleaning surface 20c facing downward. The transfer residual toner scraped from the photosensitive member 10 by the blade 20a according to the third embodiment is splashed downward with respect to the cleaning surface 20c (white arrows in FIG. 6).

  The deposit desorbing member 24 according to the third embodiment has an inclined surface 24c. The inclined surface 24 c extends obliquely downward toward the photosensitive member 10. The toner and the external additive collected by the deposit desorbing member 24 are supplied to the surface of the photosensitive member 10 down the inclined surface 24c by gravity when a certain amount is accumulated. The toner and the external additive supplied to the surface of the photosensitive member 10 are carried to the contact portion S by the photosensitive member 10 rotating in the DR1 direction, so the stationary layer L is held.

  Also in the cleaning device 1 according to the third embodiment, the effect of suppressing the wear of the blade 20a can be obtained as in the cleaning device 1 according to the first embodiment.

Embodiment 4
FIG. 7 is a schematic cross-sectional view of the vicinity of the cleaning device 1 according to the fourth embodiment. Cleaning device 1 according to the fourth embodiment includes a crosslink preventing member 27. The cross-linking preventing member 27 presses the waste toner accumulated in the housing 22 to prevent cross-linking of the waste toner.

  The deposit desorbing member 24 according to the fourth embodiment is shaken to release the collected toner and the external additive. The cross-linking preventing member 27 is used as a means for shaking the deposit desorbing member 24. The cross-linking preventing member 27 has a shape extending in the longitudinal direction (in the depth direction in FIG. 7). The cross-linking preventing member 27 presses and vibrates the deposit desorbing member 24 uniformly in the longitudinal direction. Therefore, a configuration in which several points on the cross-linking preventing member 27 in the longitudinal direction and the attached matter removing member 24 are in contact with each other is preferable.

  When the crosslinking prevention member 27 does not vibrate the attached matter detachment member 24, the crosslinking prevention member 27 and the attached matter detachment member 24 operate in a range where they do not contact each other. When it is desired to vibrate the attached matter removing member 24, the crosslinking prevention member 27 is caused to collide with the attached matter removing member 24 using a solenoid or the like. The deposit desorbing member 24 is pressed by the crosslink preventing member 27 to release the collected developer.

  The attached matter desorbing member 24 is able to separate the collected toner and the external additive from the adhered matter desorbing member 24 by being vibrated at a predetermined timing. The control unit 30 separates the collected developer according to the rotation amount of the photosensitive member 10 acquired by the rotation amount acquisition unit 31 a and the coverage information of the recording medium T acquired by the coverage acquisition unit 31 b. The attached matter desorbing member 24 is controlled. According to the rotation amount of the photosensitive member 10 and the coverage of the recording medium T, the control unit 30 vibrates the crosslink preventing member 27 to stably hold the stationary layer L in a fixed amount.

  FIG. 8 is a diagram showing an example of control for stably holding a fixed amount of stationary layer L. In FIG. When the average coverage is 0% or more and less than 5%, the amount of toner applied to the photosensitive member 10 is small, so the stationary layer L is gradually reduced. Therefore, when the rotation amount of the photosensitive member 10 is 0 mm or more and less than 500 mm, the control unit 30 causes the crosslink preventing member 27 to vibrate the attached matter removing member 24. Thereby, the reduction of the stationary layer L can be suppressed.

  However, as the amount of rotation of the photosensitive member 10 increases, the stationary layer L gradually decreases. Therefore, when the rotation amount of the photosensitive member 10 is 500 mm or more and less than 1000 mm, the developing unit 4 creates a toner band. As a result, toner is supplied to the surface of the photosensitive member 10, and the stationary layer L becomes large.

  Thereafter, the same control as described above is repeated. That is, when the amount of rotation of the photosensitive member 10 is 1000 mm or more and less than 1500 mm, the attached matter removing member 24 is oscillated again, and the amount of rotation of the photosensitive member 10 is 1500 mm or more and 2000 mm or less Create a toner band at the time of

  By controlling the deposit desorbing member 24 and the developing unit 4 in accordance with the amount of rotation of the photosensitive member 10 and the average coverage of the recording medium T, it is possible to stably hold a fixed amount of the stationary layer L. Thereby, wear of the blade 20a can be suppressed.

Fifth Embodiment
The control unit 30 according to the fifth embodiment applies a DC bias of the same polarity as that of the toner to the attached matter removing member 24 according to the rotation amount of the photosensitive member 10 and the information of the coverage of the recording medium T. Thereby, the collected toner is released.

  Also in the cleaning device 1 according to the fifth embodiment, the effect of suppressing the wear of the blade 20a can be obtained as in the cleaning device 1 according to the first embodiment.

  Note that by applying an AC bias (AC bias: including a rectangular wave and a triangular wave) to the deposit desorbing member 24 according to the fifth embodiment, the charge possessed by the collected toner and external additive is removed by charge and collected. The developer may be configured to be released.

  In addition, a DC bias of the same polarity as the external additive may be applied to the attached matter desorbing member 24 according to the fifth embodiment to separate the collected external additive. Furthermore, positive and negative DC biases can be repeatedly applied to release the collected toner and external additive as a rectangular wave (AC bias).

  For the photosensitive member 10, the exposure unit 3, the developing unit 4, the cleaning unit 9, the transfer belt 5, the primary transfer unit 50, the fixing unit 11 and the like used in the image forming apparatus 100, any known electrophotographic technology is selected. , May be used.

  The member to be cleaned may be a transfer belt (including a primary transfer belt and a secondary transfer belt). The cleaning device 1 can also be used to clean a belt such as a transfer belt.

  In the cleaning device 1 according to the fourth embodiment, even if the cross-linking preventing member 27 is not configured to vibrate the attached / detachment member 24, a vibrating member solely for the purpose of vibrating the attached / detachable member 24 is separately provided. It may be set. In addition, the control unit 30 applies an AC bias (DC bias) to the deposit desorbing member 24 according to the rotation amount and coverage of the photosensitive member 10 to separate the collected toner and the external additive. It may be.

  The cleaning device for bizhub C287 manufactured by Konica Minolta Co., Ltd. was modified, and the attached matter removing member was disposed on the upstream side in the rotational direction of the photosensitive member. The wear width of the blade was evaluated using the modified cleaning device. The environment in the evaluation test was 23 ° C. × 65% RH. A horizontal band (a band-like toner image extending in the width direction of the recording medium) was printed on 100,000 A4Y sheets. Test with 2 patterns of printing a document with horizontal band 5 [%] (coverage 5%) and a pattern of alternately printing 500 sheets of horizontal band 5 [%] and horizontal band 0 [%] every 500 sheets Carried out. The wear width was measured by microscopic observation of the blade portion. When measuring the wear width, the support member of the cleaning blade was held at an angle of 45 [deg.] From the horizontal plane, and the image was observed with an image observed with a microscope standing upright. It measured about three places of "the back", "center", and "front" in the long side direction of a blade part. If the wear width exceeds 15 μm, a cleaning failure occurs.

  FIG. 9 is a table showing the measurement results of the wear width of the blade portion. The case where the cleaning failure occurs is indicated as “not”, and the case where the cleaning failure does not occur is indicated as “OK”. A cleaning failure occurred in Comparative Example 1 and Comparative Example 2 in which the deposit desorbing member was not provided. When Example 1 and Comparative Example 1 are compared, it can be seen that the increase in the wear width of the blade portion can be suppressed by providing the deposit desorbing member.

  When Comparative Example 1 and Comparative Example 2 are compared, the wear width of the blade portion of Comparative Example 2 is larger. The comparative example 2 is a pattern in which the document of the horizontal band 5 [%] and the horizontal band 0 [%] is printed alternately, so the average coverage of the document is small compared to the comparative example 1. Therefore, the wear width of the blade portion is larger in Comparative Example 2 than in Comparative Example 1.

  However, comparing Example 2 and Comparative Example 2 in which the average coverage of the document is small, it can be seen that an increase in the wear width of the blade portion can be suppressed by providing the deposit desorbing member of the present invention in the cleaning device. .

  When Example 2 and Example 3 are compared, it is understood that the wear width of the blade portion can be further suppressed by providing the corner portion. When Example 3 and Example 4 are compared, the collected toner and external additive are released by vibrating the deposit desorbing member or applying a bias to the deposit desorbing member, and the wear width of the blade portion is determined. It turns out that it can suppress further. When Example 4 and Example 5 are compared, it can be seen that the wear width of the blade portion can be further suppressed by applying the configuration for creating the toner band.

  As described above, it has been shown that by applying the cleaning device according to the embodiment, the wear of the blade portion can be suppressed and the occurrence of cleaning failure can be suppressed.

  It should be understood that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is indicated not by the above description but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

  DESCRIPTION OF SYMBOLS 1 cleaning device, 4 developing unit, 10 photoconductor, 20 cleaning blade, 20c cleaning surface, 20b support member, 22 housing, 23 conveyance screw, 24 attached matter removing member, 24c inclined surface, 25 seal member, 26 protrusion, 26a Corner, 27 Crosslinking prevention member, 30 Control unit, 31 Information acquisition unit, 100 Image forming apparatus, S Contact unit.

Claims (18)

A cleaning blade for cleaning the cleaning target rotating member by pressing the cleaning target rotating member to which the developer adheres on the surface;
And an attached / detachment removing member provided on the upstream side in the rotational direction of the cleaning target rotating member with respect to the contact portion where the cleaning blade and the cleaning target rotating member are in contact with each other.
The attached matter removing member is configured to collect the developer scraped off and scattered from the cleaning target rotating member by the cleaning blade, and to supply the collected developer to the contact portion. apparatus.   The cleaning device according to claim 1, wherein the deposit desorbing member is electrically conductive and grounded. A housing in which the cleaning blade and the deposit desorbing member are accommodated;
A sealing member which seals the scattered developer so as not to leak to the outside of the housing, and is provided in contact with the surface of the cleaning member to be cleaned;
The cleaning device according to claim 1 or 2, wherein the deposit desorbing member is provided so as to overlap the seal member inside the housing. The cleaning blade has a cleaning surface facing upward,
The cleaning surface includes the contact portion,
The cleaning apparatus according to any one of claims 1 to 3, wherein the attached matter removing member is provided substantially immediately above the cleaning surface. The attached matter desorbing member includes a protrusion which protrudes toward the cleaning surface and has a corner at the protruding tip.
The cleaning device according to claim 4, wherein the corner portion is provided substantially immediately above the cleaning surface.   The cleaning apparatus according to claim 5, wherein the deposit desorbing member has a V shape forming the protrusion. The cleaning blade has a cleaning surface facing downward,
The cleaning surface includes the contact portion,
The cleaning apparatus according to any one of claims 1 to 3, wherein the attached matter removing member has an inclined surface extending obliquely downward toward the cleaning target rotating member. The developer contains toner,
The attached matter desorbing member is configured to collect toner scattered and scattered from the cleaning target rotating member by the cleaning blade by applying a bias having a reverse polarity to the toner. The cleaning device according to any one of the above. The developer contains an external additive,
The attached matter desorbing member collects the external additive scraped off and scattered from the cleaning target rotating member by the cleaning blade by applying a bias having a reverse polarity to the external additive. The cleaning device according to any one of claims 8 to 10. The developer contains toner,
10. The attached matter desorbing member according to any one of claims 1 to 9, wherein the application of the bias having the same polarity as the toner desorbs the toner collected by the attached matter desorbing member. Cleaning device. The developer contains an external additive,
11. The attached matter desorbing member according to claim 1, wherein the applied matter desorbing member separates the external additive collected by applying a bias having the same polarity as the external additive. Cleaning device described in the section.   The cleaning device according to any one of claims 1 to 11, wherein the attached matter desorbing member is shaken to release the collected developer. It further comprises a cross-linking preventing member that prevents cross-linking of the toner,
The cleaning device according to claim 12, wherein the attached matter desorbing member separates the collected developer by being pressed by the crosslink preventing member.   The cleaning device according to any one of claims 1 to 13, wherein the attached matter desorbing member separates the collected developer by applying an AC bias. A developing unit for applying a developer to the cleaning member to be cleaned;
An image forming apparatus, comprising: the cleaning device according to any one of claims 1 to 14, which cleans the developer attached to the cleaning target rotating member. An information acquisition unit for acquiring the amount of rotation of the cleaning target rotating member and the coverage of the recording medium on which an image is formed;
The controller according to claim 15, further comprising: a control unit configured to control the attached matter desorbing member to release the collected developer according to the amount of rotation and the coverage acquired by the information acquiring unit. Image forming apparatus.   The image forming apparatus according to claim 16, wherein the control unit controls the developing unit to apply the developer to the cleaning target rotating member according to the amount of rotation and the coverage acquired by the information acquiring unit. apparatus. The recording medium has a plurality of divided areas aligned in a direction orthogonal to the conveyance direction of the recording medium,
The image forming apparatus according to claim 16, wherein the information acquisition unit acquires coverage for each of the plurality of divided areas.

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