Cleaning device and image forming apparatus

Abstract

To collect a substance to be collected with a simpler configuration.SOLUTION: A cleaning device has: collection means that is rotatable and collects a substance to be collected on a surface to be cleaned with static electricity; charging means that rotates while in contact with the collection means, and triboelectrically charges a peripheral surface of the collection means; and recovery means that rotates while in contact with the collection means, and recovers the substance to be collected attached to the peripheral surface of the collection means. In the direction of rotation of the collection means, the collection means and the surface to be cleaned are in contact with each other at a first position, the collection means and the recovery means are in contact with each other at a second position, and the collection means and the charging means are in contact with each other at a third position. Along the direction of rotation of the collection means, the first position, the second position, and the third position are arranged in order. The direction of rotation of the collection means is the same as the direction of rotation of the charging means. The direction of rotation of the collection means is opposite to the direction of rotation of the recovery means.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a cleaning device and an image forming apparatus. [Background technology]

[0002] Currently, technologies have been developed for collecting or removing foreign matter or unnecessary substances using electrostatic adsorption in various manufacturing facilities or industrial products. Patent Document 1 discloses a technology for collecting or removing foreign matter attached to the surface of a glass substrate, a printed circuit board, a film, a sheet, or a plastic plate by electrostatic adsorption. Patent Document 2 discloses an image forming device for collecting or removing paper powder attached to the surface of paper by electrostatic adsorption. Patent Document 3 discloses a brush for attracting toner attached to the surface of a photoconductor, a collection roller for collecting the toner from the brush, and a cleaning blade for removing the toner from the collection roller. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4886097 [Patent Document 2] JP 2017-156450 A [Patent Document 3] JP 2007-132999 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional technology requires a power supply device that applies a high voltage to the collection member that collects the objects to be collected, and high-voltage wiring that supplies the high voltage to the collection member. Therefore, an object of the present invention is to recover the objects to be collected with a simpler configuration. [Means for solving the problem]

[0005] The present invention relates to, for example, A rotatable collecting means for electrostatically collecting objects on a surface to be cleaned; an electrifying means that rotates while in contact with the collecting means and frictionally electrifies the circumferential surface of the collecting means; a collecting means that rotates while in contact with the collecting means and collects the objects to be collected that are attached to the circumferential surface of the collecting means, In the rotation direction of the collection means, the collection means and the surface to be cleaned are in contact with each other at a first position, In the rotation direction of the collection means, the collection means and the recovery means are in contact with each other at a second position, the collecting means and the charging means are in contact with each other at a third position in the rotation direction of the collecting means, the first position, the second position, and the third position are arranged in order along the rotation direction of the collection means, the rotation direction of the collecting means is the same as the rotation direction of the charging means, A cleaning apparatus is provided, wherein the direction of rotation of the collecting means is opposite to the direction of rotation of the recovery means. Effect of the Invention

[0006] According to the present invention, it is possible to recover the objects to be collected with a simpler configuration. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating an image forming apparatus. [Diagram 2] A diagram illustrating a cleaning device. [Diagram 3] Diagram explaining the triboelectric series [Figure 4] Diagram explaining the experimental results (evaluation results) [Diagram 5] FIG. 1 is a diagram for explaining an image forming apparatus according to a second embodiment of the present invention; [Figure 6] FIG. 10 is a diagram illustrating a cleaning device according to a second embodiment. [Figure 7] FIG. 11 is a diagram for explaining an image forming apparatus according to a third embodiment of the present invention; [Figure 8]FIG. 11 is a diagram illustrating a cleaning device according to a third embodiment. [Figure 9] FIG. 10 is a diagram illustrating a cleaning device according to a fourth embodiment. [Figure 10] FIG. 10 is a diagram illustrating a cleaning device according to a fourth embodiment. [Figure 11] FIG. 10 is a diagram illustrating a cleaning device according to a fourth embodiment. [Figure 12] FIG. 10 is a diagram illustrating a cleaning device according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0009] <Example 1> A cleaning device mounted on an image forming apparatus will be described in Example 1. The cleaning device is used, for example, to clean a developer (e.g., toner) used to form an image in the image forming apparatus.

[0010] (1) Structure of the image forming device 1 shows an image forming apparatus 100 that forms a full-color image by electrophotography. The lowercase alphabets at the end of the reference numbers indicate the toner colors (yellow, magenta, cyan, and black). When matters common to all four colors are explained, the letters ymck may be omitted from the reference numbers.

[0011] The photosensitive drum 1 is an image carrier that rotates while carrying an electrostatic latent image or a toner image. The charging member 2 is a charger (e.g., a charging roller or a metal wire) that uniformly charges the surface of the photosensitive drum 1. The exposure device 3 exposes the surface of the photosensitive drum 1 to laser light according to image data to form an electrostatic latent image. The development device 4 contains toner and supplies the toner to the electrostatic latent image via the development roller 5. This develops the electrostatic latent image to form a toner image. The primary transfer roller 6 transfers the toner image from the photosensitive drum 1 to the intermediate transfer belt 7. The intermediate transfer belt 7 is an endless intermediate transfer body. The yellow, magenta, cyan, and black toner images are transferred in order onto the intermediate transfer belt 7 to form a full-color toner image. As the intermediate transfer belt 7 rotates, the toner image is transported to the secondary transfer section. The secondary transfer section is formed by the intermediate transfer belt 7 and the secondary transfer roller 13.

[0012] The sheet cassette 10 is a container that holds a large number of sheets P. The feed rollers 11 feed the sheets P one by one from the sheet cassette 10. When the sheet P abuts against the registration rollers 12, any skew of the sheet P is corrected. The registration rollers 12 transport the sheet P to a secondary transfer unit.

[0013] In the secondary transfer portion, a secondary transfer roller 13 transfers the toner image from the intermediate transfer belt 7 to a sheet P. A fixing device 14 fixes the toner image onto the sheet P by applying heat and pressure to the toner image and the sheet P. Thereafter, the sheet P is discharged onto a discharge tray 15.

[0014] Incidentally, even after the secondary transfer is completed, toner may remain on the surface of the intermediate transfer belt 7. Therefore, the cleaning device 20 cleans and collects the toner remaining on the surface of the intermediate transfer belt 7.

[0015] (2) Structure of the cleaning device 2, the cleaning device 20 collects the toner T adhering to the intermediate transfer belt 7. The intermediate transfer belt 7 is suspended on a suspension roller 29 and rotated in the direction of the arrow. The suspension roller 29 is made of a conductor such as aluminum. The suspension roller 29 is grounded to the frame ground (GND) through the main body frame and an earth cable.

[0016] The cleaning device 20 includes a collection roller 21, a charging roller 22, a discharging sheet 23, a recovery roller 26, a blade 24, and a container 25. The collection roller 21 includes a collection brush 21a and a core body 21b. The collection brush 21a is held by the core body 21b. The collection roller 21 rotates around the core body 21b, which is rotatably supported by the main body frame, as a rotation axis.

[0017] Collection roller 21 contacts intermediate transfer belt 7 at contact position P1. Collection roller 21 contacts recovery roller 26 at contact position P2. Collection roller 21 contacts charging roller 22 at contact position P3. In the rotation direction of collection roller 21, contact position P1 is upstream of contact position P2, and contact position P2 is upstream of contact position P3. In other words, contact position P1, contact position P2, and contact position P3 are lined up in this order along the rotation direction of collection roller 21.

[0018] The charging roller 22 has a charging brush 22a and a core body 22b. The charging brush 22a is held by the core body 22b. The charging roller 22 rotates around the core body 22b, which is rotatably supported by the main body frame, as a rotation axis. The charging roller 22 frictionally charges the surface of the collecting roller 21 while rotating.

[0019] The recovery roller 26 has a surface layer 26a and a core body 26b. The surface layer 26a is held by the core body 26b. The recovery roller 26 rotates around the core body 26b, which is rotatably supported by the main body frame, as a rotation axis.

[0020] (3) Rotation direction 2, collection roller 21 rotates counterclockwise. Recovery roller 26 rotates clockwise. Charging roller 22 also rotates counterclockwise. Looking at the two rotating bodies in contact with each other, the contact portion of collection roller 21 and the contact portion of collection roller 26 move in the same direction (forward direction) with respect to each other. On the other hand, the contact portion of collection roller 21 and the contact portion of charging roller 22 move in opposite directions.

[0021] (4) Material of collection roller The collecting brush 21a has a large number of piles. The pile material is, for example, polyethylene terephthalate (PET). The pile fineness is, for example, 10D. The pile length is, for example, 5 mm. The density is 30 kF / inch2. The outer diameter of the collecting roller 21 is, for example, 30 mm. The shaft rotation speed is, for example, 50 rpm. In this case, the surface movement speed of the collecting roller 21 is 78.5 mm / s.

[0022] (5) Material of the collection roller The material of surface layer 26a of recovery roller 26 is, for example, nylon. The thickness is, for example, 0.5 mm. The outer diameter of recovery roller 26 is, for example, 24 mm. The shaft rotation speed is, for example, 80 rpm. In this case, the surface movement speed of recovery roller 26 is 100.5 mm / s. The surface movement speed of recovery roller 26 is higher than the surface movement speed of collection roller 21.

[0023] (6)Charging roller material The pile material of the charging brush 22a of the charging roller 22 is, for example, perfluoroalkoxy fluororesin (PFA). The pile fineness is, for example, 10D. The pile length is, for example, 3 mm. The pile density is, for example, 50 kF / inch2. The outer diameter of the charging roller 22 is, for example, 18 mm. In this case, the shaft rotation speed is 30 rpm. In this case, the surface movement speed of the charging roller 22 is 28.7 mm / s.

[0024] (7) Toner recovery process and materials of each component (7-1) From the intermediate transfer belt to the collection roller The toner T remaining on the surface of the intermediate transfer belt 7 is collected in the container 25 through the following process. The toner T is negatively charged by an external additive that controls the chargeability. Therefore, the surface of the collection roller 21 only needs to be positively charged in order to collect the toner T. The collection roller 21 collects the toner T on the intermediate transfer belt 7 by electrostatic adsorption force.

[0025] (7-2) From the collection roller to the recovery roller The toner T attracted to the collection roller 21 is transferred from the collection roller 21 to the collection roller 26. A condition for promoting this transfer is that the collection roller 26 is charged more positively than the collection roller 21. This generates an electrostatic attraction force from the collection roller 21 toward the collection roller 26, and the toner T moves from the collection roller 21 to the collection roller 26.

[0026] In the first embodiment, frictional charging occurs between multiple members (rotating bodies) without using an external power source. This controls the charge polarity and charge amount. In general, the charge polarity and charge amount are determined by a triboelectric series. When two materials are frictionally charged, one of the two materials becomes positively charged and the other negatively charged. This charge polarity and charge amount depend on the materials of the two materials. A triboelectric series arranges various materials based on their relative ease of charging. In a triboelectric series, the farther apart the two materials are, the greater the charge amount.

[0027] FIG. 3 shows an example of a triboelectric series. In order to collect and transfer the negatively charged toner T, the surface layer 26a of the collection roller 26 must be located on the positive side of the collection brush 21a in the triboelectric series. The collection brush 21a must be located on the positive side of the charging brush 22a. In other words, the surface layer 26a of the collection roller 26, the collection brush 21a, and the charging brush 22a must be arranged in this order from the positive side to the negative side in the triboelectric series. In other words, the surface layer 26a of the collection roller 26 is more likely to be charged to the positive side than the collection brush 21a, and the collection brush 21a is more likely to be charged to the positive side than the charging brush 22a. In other words, the charging brush 22a is more likely to be charged to the negative side than the collection brush 21a, and the collection brush 21a is more likely to be charged to the negative side than the surface layer 26a of the collection roller 26. In a triboelectric series, it is possible to determine which of two materials is on the positive side by rubbing the two materials together and measuring their polarity with a surface electrometer.

[0028] Wool, nylon, rayon, or the like, which are on the positive side of the triboelectric series, may be used as the material for the surface layer 26a of the recovery roller 26. In the first embodiment, nylon is used as the material for the surface layer 26a of the recovery roller 26.

[0029] As the material of the charging brush 22a, a fluororesin, which is on the negative side in the triboelectric series, can be used. Examples of fluororesins include polytetrafluoroethylene (PTFE), silicone, polychlorotrifluoroethylene (PCTFE, CTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), PFA, tetrafluoroethylene-hexafluoropolypropylene copolymer (FEP), ethylene-tetrafluoroethylene copolymer (ETFE), and ethylene-chlorotrifluoroethylene copolymer (ECTFE). In the first embodiment, PFA is used as the material of the charging brush 22a.

[0030] The material of the collection brush 21a may be any material that is between nylon and PFA in the triboelectric series, and therefore, in the first embodiment, PET was used.

[0031] As shown in FIG. 2, the static elimination sheet 23 is disposed so as to contact the charging brush 22a. The static elimination sheet 23 is made of a conductive sheet. The static elimination sheet 23 is grounded to a GND such as a main body frame to which no bias is applied. As a result, the charge stored in the charging brush 22a is directed toward the GND due to the friction between the collecting brush 21a and the charging brush 22a. When the charging roller 22 rotates and rubs against the collecting brush 21a again, the charge amount of the charging roller 22 becomes greater than the charge amount of the collecting brush 21a. Compared to the charge amount of the collecting brush 21a without the static elimination sheet 23, the charge amount of the collecting brush 21a with the static elimination sheet 23 is greater.

[0032] For example, polyurethane resin having elasticity is used as the material of the blade 24. As a result, the blade 24 scrapes off the toner T adhering to the collection roller 26 and collects the toner T in the container 25. The collected toner T accumulates in the container 25.

[0033] (8) Verification of effectiveness The cleaning performance of the intermediate transfer belt 7 was evaluated for Example 1, Comparative Examples 1 and 2, and Modifications 1 to 4. The differences between Example 1, Comparative Examples 1 and 2, and Modifications 1 to 4 are as follows.

[0034] Comparative Example 1: The rotation direction of the recovery roller 26 is changed to counterclockwise. The contact portion of the collection roller 21 and the contact portion of the recovery roller 26 move in the opposite directions.

[0035] Comparative Example 2: The rotation direction of charging roller 22 is changed to clockwise. The contact portion of collection roller 21 and the contact portion of charging roller 22 move in the forward direction relative to each other.

[0036] Modification 1: Collection roller 21 is changed to a solid roller. The outer diameter of collection roller 21 is not changed. The outermost layer of collection roller 21 is made of PET and has a thickness of 0.5 mm. An intermediate layer of foamed silicone rubber is inserted between the outermost layer and core body 21b as an elastic layer.

[0037] Modification 2: The charging roller 22 is changed to a solid roller. The outer diameter of the charging roller 22 is not changed. The material of the outermost layer of the charging roller 22 is PFA. The thickness is 0.5 mm. An intermediate layer of foamed silicone rubber is inserted between the outermost layer and the core body 21b as an elastic layer.

[0038] Modification 3: The axial rotation speed of recovery roller 26 is changed to 50 rpm. The surface movement speed of recovery roller 26 is 62.8 mm / s. This is smaller than the surface movement speed of collection roller 21 (78.5 mm / s).

[0039] Modification 4: The static elimination sheet 23 is omitted.

[0040] The cleaning performance was evaluated as follows. Images were formed on 1000 sheets P using yellow and magenta. The sheets P were A4 size GF-C081 paper (manufactured by Canon Inc.). Here, the density of yellow and the density of magenta were each 100%. The amount of these toners was 1.0 mg / cm2. When the image formation on the 1000 sheets P was completed, the state of collection of the toner T by the cleaning device 20 was confirmed. For reference, when an image formed by overlapping two colors of toner is continuously printed on 1000 sheets P, the amount of toner remaining on the intermediate transfer belt 7 increases. In other words, this is a severe cleaning condition for the cleaning device 20.

[0041] FIG. 4 shows the experimental results (evaluation results). In FIG. 4, "GOOD" refers to a state where there is no cleaning defect. An example of a cleaning defect is when streaky toner remains on the surface of the intermediate transfer belt 7 that has passed through the cleaning device 20. "NOT BAD" refers to the fact that several streaks were observed when printing on 100 sheets P was completed. "NOT GOOD" refers to the fact that several streaks were observed when printing on 50 sheets P was completed. "BAD" refers to the fact that several streaks were observed when printing on 10 sheets P was completed.

[0042] In Comparative Example 1, the movement direction of the contact portion of collection roller 21 and the movement direction of the contact portion of collection roller 26 were opposite. Therefore, in the nip region formed by the contact between collection roller 21 and collection roller 26, the opportunity (time) for toner T adhering to collection roller 21 to adhere to collection roller 26 was reduced. This is thought to have reduced the transferability to collection roller 26, increased the amount of toner T remaining on collection roller 21, and increased cleaning defects. Therefore, if the movement direction of the contact portion of collection roller 21 and the movement direction of the contact portion of collection roller 26 are forward, the cleaning effect is improved.

[0043] In Comparative Example 2, the movement direction of the contact portion of collection roller 21 and the movement direction of the contact portion of charging roller 22 were the same. Therefore, the amount of charge of collection roller 21 due to frictional charging decreased. As a result, it is believed that the collection ability of toner T decreased and poor cleaning occurred. Therefore, if the movement direction of the contact portion of collection roller 21 and the movement direction of the contact portion of charging roller 22 were opposite, the cleaning effect would be improved.

[0044] In the first modification, the collection roller 21 is changed from a brush roller to a solid roller. This significantly reduces the surface area of ​​the collection roller 21, reducing the opportunities for the collection roller 21 to come into contact with the toner T on the intermediate transfer belt 7. As a result, it is believed that the collection of the toner T is reduced, causing poor cleaning. Therefore, if the collection roller 21 were a brush roller, the cleaning effect would be improved.

[0045] In the second modification, the charging roller 22 is changed from a brush roller to a solid roller. This reduces the chance of contact with the toner. It is believed that the amount of charge on the collection roller 21 due to frictional charging decreases, which reduces the ability to collect the toner T and causes poor cleaning. Therefore, if the charging roller 22 were a brush roller, the cleaning effect would be improved.

[0046] In the third modification, the surface movement speed of the collection roller 21 is higher than that of the collection roller 26. The surface movement area per unit time of the collection roller 26 is smaller than that of the collection roller 21. For this reason, it is considered that the transfer efficiency of the toner T from the collection roller 21 to the collection roller 26 is reduced, causing a cleaning failure. Therefore, if the surface movement speed of the collection roller 26 is higher than that of the collection roller 21, the cleaning effect is improved.

[0047] In the fourth modification, the static elimination sheet 23 is omitted. Therefore, the charging roller 22 is charged up, and the amount of charge on the collection roller 21 due to frictional charging gradually decreases. As a result, the ability to collect the toner T decreases, and it is believed that a cleaning failure occurs. Therefore, by disposing the static elimination sheet 23 on the charging roller 22, the cleaning effect is improved.

[0048] In Example 1, the moving direction of the contact portion of the collecting roller 21 and the moving direction of the contact portion of the charging roller 22 are opposite. The collecting roller 21 is a brush roller. The charging roller 22 is a brush roller. This increases the amount of charge of the collecting roller 21 due to frictional charging. The moving direction of the contact portion of the collecting roller 21 and the moving direction of the contact portion of the collecting roller 26 are the same. This increases the opportunity for the toner T adhering to the collecting roller 21 to adhere to the collecting roller 26, improving the transferability to the collecting roller 26. The surface moving speed of the collecting roller 21 is smaller than the surface moving speed of the collecting roller 26. In other words, the moving area per unit time of the collecting roller 26 is relatively large. This improves the transferability of the toner from the collecting roller 21 to the collecting roller 26. When the static elimination sheet 23 is adopted, the charge-up of the charging roller 22 is suppressed, and the amount of charge of the collecting roller 21 due to frictional charging increases. Therefore, Example 1 was able to maintain better cleaning performance than other comparative examples.

[0049] In the first embodiment, the circumferential surface of the intermediate transfer belt 7 is used as the surface to be cleaned. However, this is merely an example. The surface to be cleaned may be a transfer material transport body that attracts and transports the sheet P, which is a transfer material.

[0050] <Example 2> (1) Overview In the second embodiment, an image forming apparatus 500 that forms a monochrome image using an electrophotographic method will be described. Furthermore, toner T remaining on a photoconductor drum 1, which is an image carrier, is collected by a cleaning device 20.

[0051] (2) Structure of the image forming device Fig. 5 shows the structure of an image forming apparatus 500 according to a second embodiment. In Fig. 5, the same reference numerals are given to the same items as in Fig. 1, and the description thereof will be omitted. Although an intermediate transfer belt 7 is used in Fig. 1, the intermediate transfer belt 7 is omitted in Fig. 5. Thus, the primary transfer roller 6 transfers the toner image from the photosensitive drum 1 to the sheet P.

[0052] (3)Cleaning device As shown in FIG. 5, the cleaning device 20 is disposed so as to come into contact with the photosensitive drum 1 in order to collect the toner T remaining on the photosensitive drum 1.

[0053] FIG. 6 shows the structure of the cleaning device 20 of the second embodiment. The structure of the cleaning device 20 of the second embodiment is basically the same as that of the cleaning device 20 of the first embodiment. The collecting roller 21 is disposed so as to face the photosensitive drum 1 to be cleaned. The charging roller 22 is disposed so as to face the collecting roller 21, and frictionally charges the collecting roller 21. The collecting roller 26 is disposed so as to face the collecting roller 21, and collects the toner T from the collecting roller 21 to the collecting roller 26. The discharging sheet 23 is disposed so as to come into contact with the charging roller 22, and releases the charge of the charging roller 22 to the GND. The discharging sheet 23 is connected to a frequency ground (GND). The blade 24 collects the toner T from the collecting roller 26 to a container 25.

[0054] As described in the first embodiment, the toner T is negatively charged. Therefore, the structure of the cleaning device 20 in the second embodiment is the same as that of the cleaning device in the first embodiment.

[0055] 6, the rotation direction of collection roller 21 is clockwise. The rotation direction of collection roller 26 is counterclockwise. The rotation direction of charging roller 22 is clockwise. That is, the movement direction of the contact portion of collection roller 21 is the same as the movement direction of the contact portion of collection roller 26. The movement direction of the contact portion of collection roller 21 is opposite to the movement direction of the contact portion of charging roller 22. Therefore, the rotation direction conditions in Example 2 are the same as the rotation direction conditions in Example 1.

[0056] In the second embodiment, the collecting roller 21 is also a brush roller. The material of the brush is, for example, PET. The material of the surface layer of the recovery roller 26 is, for example, nylon. The charging roller 22 is also a brush roller. The material of the brush is, for example, PFA.

[0057] Therefore, the cleaning effect in the embodiment 2 is expected to be equivalent to that in the embodiment 1. As a result, a simpler cleaning device 20 is realized without employing a dedicated high-voltage power supply (charging power supply) for the cleaning device 20.

[0058] <Example 3> (1) Overview In the third embodiment, paper dust from the sheet P is actively collected before the sheet P passes through the photosensitive drum 1. This reduces the amount of paper dust adhering to the photosensitive drum 1, suppressing the occurrence of image defects. In the third embodiment, the same reference numerals are given to configurations that are substantially the same as or similar to those in the second embodiment, and descriptions thereof will be omitted.

[0059] (2) Image forming device 7 shows an image forming apparatus 500 according to a third embodiment. A cleaning device 70 is disposed upstream of the photoconductor drum 1 and the primary transfer roller 6 in the conveying direction of the sheet P. The cleaning device 70 is a device that cleans and collects paper dust adhering to the sheet P.

[0060] (3)Cleaning device 8 shows the structure of the developing device 4 in the third embodiment. A cleaning device 70 is provided on the lower side of the developing device 4 so as to face the transport path of the sheet P. Like the cleaning device 20, the cleaning device 70 has a collection roller 21, a charging roller 22, a static elimination sheet 23, a recovery roller 26, a blade 24, and a container 25. The container 25 is a paper dust container that contains paper dust recovered from the sheet P.

[0061] The collecting roller 21 is disposed so as to face the sheet P to be cleaned. The charging roller 22 is disposed so as to face the collecting roller 21, and frictionally charges the collecting roller 21. The collecting roller 26 is disposed so as to face the collecting roller 21, and collects the paper powder from the collecting roller 21 to the collecting roller 26. The discharging sheet 23 is disposed so as to come into contact with the charging roller 22, and releases the charge of the charging roller 22 to GND. The discharging sheet 23 is connected to a frequency ground (GND). The blade 24 collects the paper powder from the collecting roller 26 to a container 25.

[0062] As shown in Fig. 8, the rotation direction of collection roller 21 is clockwise. The rotation direction of collection roller 26 is counterclockwise. The rotation direction of charging roller 22 is clockwise. That is, the movement direction of the contact portion of collection roller 21 is the same as the movement direction of the contact portion of collection roller 26. The movement direction of the contact portion of collection roller 21 is opposite to the movement direction of the contact portion of charging roller 22. Therefore, the rotation direction conditions in Example 3 are the same as the rotation direction conditions in Examples 1 and 2.

[0063] In the third embodiment, it is required to reduce the stress caused by the friction between the sheet P and the collection roller 21. Therefore, the rotation direction of the collection roller 21 is set so that the movement direction of the collection roller 21 relative to the sheet P coincides with the conveyance direction of the sheet P.

[0064] In the first and second embodiments, the cleaning device 20 collects negatively charged toner T. The cleaning device 70 in the third embodiment collects paper dust from the sheet P. Paper dust is generally positively charged. Therefore, the charge polarity of the object to be cleaned in the third embodiment is opposite to that of the object to be cleaned in the first and second embodiments.

[0065] Therefore, in the third embodiment, the materials of the collection roller 26, the collection roller 21, and the charging roller 22 are selected so that they are arranged from the negative side to the positive side in the triboelectric series. In the third embodiment, for example, the collection roller 21 is a brush roller. The brush material is PET. The surface layer material of the collection roller 26 is, for example, PFA. The charging roller 22 is a brush roller. The brush material is, for example, nylon.

[0066] In the third embodiment, similarly to the second embodiment, the static elimination sheet 23 is disposed so as to be in contact with the surface layer of the charging roller 22. The static elimination sheet 23 is made of a conductive sheet. No bias is applied to the static elimination sheet 23, and the static elimination sheet 23 is grounded to the main body frame or the like.

[0067] According to the third embodiment, paper dust that is easily released from sheet P is collected by collection roller 21. The paper dust is transferred from collection roller 21 to collection roller 26. The paper dust is scraped off collection roller 26 by blade 24 and collected in container 25. In this way, because paper dust is actively collected from sheet P before it passes through photosensitive drum 1, the amount of paper dust adhering to photosensitive drum 1 is reduced. As a result, image defects caused by paper dust and the like are less likely to occur.

[0068] In the third embodiment, the developing device 4 includes the cleaning device 70, but this is merely an example. The cleaning device 70 may be fixed to a main body frame of the image forming apparatus 500. Even in this case, the cleaning device 70 is disposed downstream of the sheet cassette 10 and upstream of the photosensitive drum 1 in the conveying direction of the sheet P.

[0069] <Example 4> (1) Overview In the fourth embodiment, a cleaning device for cleaning dust on a floor is provided. The object to be cleaned is a floor, and the object to be collected is dust present on the floor. However, the cleaning principle in the fourth embodiment is the same as the cleaning principle in the first to third embodiments.

[0070] (2)Cleaning device FIG. 9 shows the appearance of a cleaning device 90 according to a fourth embodiment. The cleaning device 90 has a housing 84 and a handle 81 connected to the housing 84. An opening 82 is provided in the front of the housing 84. The handle 81 is a gripping part that is held by a user. The user moves the cleaning device 90 in the direction indicated by the arrow D1 to rotate the collection roller 21 provided inside the housing 84. The collection roller 21 rotates while contacting the surface to be cleaned (e.g., floor F). As a result, dust H that has entered through the opening 82 is collected inside the housing 84.

[0071] FIG. 10 shows a schematic cross section of the cleaning device 90. Dust H is scattered on the floor F. The structure of the cleaning device 90 of the fourth embodiment is basically the same as the structure of the cleaning device 20 of the first embodiment. The collecting roller 21 is arranged to face the floor F to be cleaned. The charging roller 22 is arranged to face the collecting roller 21 and frictionally charges the collecting roller 21. The collecting roller 26 is arranged to face the collecting roller 21 and collects the dust H from the collecting roller 21 to the collecting roller 26. The discharging sheet 23 is arranged to contact the charging roller 22 and releases the charge of the charging roller 22 to GND. The discharging sheet 23 is connected to a frame ground (GND). The blade 24 collects the dust H from the collecting roller 26 to a container 25. The battery 87 supplies power to the motor 89. The motor 89 is, for example, a driving source for rotating the collecting roller 21, the charging roller 22, and the collecting roller 26.

[0072] The rotation direction of collection roller 21 is counterclockwise. The rotation direction of recovery roller 26 is clockwise. The rotation direction of charging roller 22 is counterclockwise. In other words, the movement direction of the contact portion of collection roller 21 is the same as the movement direction of the contact portion of recovery roller 26. The movement direction of the contact portion of collection roller 21 is opposite to the movement direction of the contact portion of charging roller 22.

[0073] Most of the dust H present in the natural world is positively charged. Therefore, in the fourth embodiment, similar to the third embodiment, the collection roller 21 is a brush roller. The brush material is PET. The surface layer 26a of the recovery roller 26 is made of PFA. The charging roller 22 is a brush roller. The brush material is nylon.

[0074] In the fourth embodiment, similarly to the second embodiment, the static elimination sheet 23 is disposed so as to be in contact with the surface layer of the charging roller 22. The static elimination sheet 23 is made of a conductive sheet. The static elimination sheet 23 is grounded to a main body frame or the like to which no bias is applied.

[0075] 11 shows the positional relationship between collection roller 21, charging roller 22, recovery roller 26, and blade 24. In Example 4, the angle θ between line L1 connecting the rotation axis center of collection roller 21 and the rotation axis center of charging roller 22 and line L2 connecting the rotation axis center of collection roller 21 and the rotation axis center of recovery roller 26 is 30°.

[0076] The dust H collected by the collecting roller 21 is transferred from the collecting roller 21 to the collecting roller 26 by electrostatic force. Ideally, more dust H is transferred to the collecting roller 26. However, the dust H may be fixed to the collecting roller 21 by non-electrostatic adhesion (e.g., adhesive force). Therefore, some of the dust H may slip through to the charging roller 22. Such some of the dust H is referred to as dust H2. Since the charging brush 22 rotates in the opposite direction to the collecting roller 21, the dust H2 is separated and freed from the collecting roller 21 by a physical knocking effect. The dust H2 is subjected to electrostatic force and adheres to the collecting roller 26. This is because the collecting roller 26 is negatively charged with a larger charge amount than the collecting roller 21. The dust H2 adhering to the collecting roller 26 is scraped off by the blade 24 and stored in the container 25.

[0077] Here, the angle θ needs only to be smaller than 90°. The angle θ may be smaller than 60°. For example, the angle θ is equal to or larger than 30° and smaller than 90°. Dust H2 adhering to collection roller 21 may be repelled by charged brush 22. With such an angle θ as exemplified above, the probability that dust H2 will be repelled along a trajectory that directly reaches collection roller 26 increases. When the distance between the point where dust H2 is liberated and the point where dust H2 adheres to collection roller 26 becomes short, electrostatic force acts strongly on dust H2. Due to these actions, dust H2 is more likely to adhere to collection roller 26.

[0078] If the angle θ is 90° or more, these effects do not work sufficiently, and the dust H2 becomes less likely to adhere to the collection roller 26 and more likely to adhere again to the collection roller 21. Then, some of the dust H2 that has adhered to the collection roller 21 may pass through the charged brush 22 and adhere again to the floor F. The dust H2 may hinder the collection of new dust H that has adhered to the floor F. The dust H2 may reduce the amount of charge on the collection roller 21 due to frictional charging with the charged brush 22. As a result, the collection of the dust H from the floor F may decrease.

[0079] 12, a guide plate 120 may be disposed between the charging roller 22 and the collection roller 26. The guide plate 120 guides the dust H2 that has been flicked off by the charging brush 22 to the collection roller 26. This makes it easier for the dust H2 to adhere to the collection roller 26.

[0080] <Other> In the first to fourth embodiments, various applications to which the technical concept of the present invention can be applied are illustrated. However, these are merely examples. For example, the cleaning devices 20, 70, and 90 may be employed to clean dust adhering to the surface of a glass substrate for a display or a semiconductor wafer. The cleaning devices 20, 70, and 90 may be employed to clean dust adhering to the surface of an electrostatic adsorption stage that holds these substrates in a vacuum chamber of a semiconductor manufacturing device.

[0081] <Technical ideas derived from examples> (Item 1) A rotatable collecting means for electrostatically collecting objects on a surface to be cleaned; an electrifying means that rotates while in contact with the collecting means and frictionally electrifies the circumferential surface of the collecting means; a collecting means that rotates while in contact with the collecting means and collects the objects to be collected that are attached to the circumferential surface of the collecting means, In the rotation direction of the collection means, the collection means and the surface to be cleaned are in contact with each other at a first position, In the rotation direction of the collection means, the collection means and the recovery means are in contact with each other at a second position, the collecting means and the charging means are in contact with each other at a third position in the rotation direction of the collecting means, the first position, the second position, and the third position are arranged in order along the rotation direction of the collection means, the rotation direction of the collecting means is the same as the rotation direction of the charging means, A cleaning apparatus, wherein the direction of rotation of the collecting means is opposite to the direction of rotation of the recovery means.

[0082] The collecting roller 21 is an example of a rotatable collecting means that collects the objects to be collected on the surface to be cleaned by static electricity. The charging roller 22 is an example of a charging means that rotates while in contact with the collecting roller 21 and frictionally charges the circumferential surface of the collecting roller 21. The collecting roller 26 is an example of a collecting means that rotates while in contact with the collecting roller 21 and collects the objects to be collected that are attached to the circumferential surface of the collecting roller 21. As illustrated in FIG. 2 and the like, in the rotation direction of the collecting roller 21, the collecting roller 21 and the surface to be cleaned are in contact with each other at a first position P1. The collecting roller 21 and the collecting roller 26 are in contact with each other at a second position P2. The collecting roller 21 and the charging roller 22 are in contact with each other at a third position P3. The first position P1 is upstream of the second position P2. The second position P2 is upstream of the third position P3. That is, the first position P1, the second position P2, and the third position P3 are arranged in order along the rotation direction of the collecting roller 21. The rotation direction of the collection roller 21 is the same as that of the charging roller 22. The rotation direction of the collection roller 21 is opposite to that of the recovery roller 26. This allows the collection roller 21 to be sufficiently charged without using an expensive high-voltage power source device. As a result, it becomes possible to recover the objects to be collected with a simpler configuration. (Item 2) 2. The cleaning device according to claim 1, wherein the collecting means comprises a collecting brush and a rotating shaft provided with the collecting brush.

[0083] The core body 21b is an example of a rotating shaft provided with the collecting brush 21a. (Item 3) 3. The cleaning device according to claim 1, wherein the charging means has a charging brush and a rotating shaft on which the charging brush is provided.

[0084] The core body 22b is an example of a rotating shaft provided with the charging brush 22a. (Item 4) 4. The cleaning device according to any one of items 1 to 3, wherein in a triboelectric series, a material forming the outer periphery of the collection means is more likely to be positively charged than a material forming the outer periphery of the collection means, and the material forming the outer periphery of the collection means is more likely to be positively charged than a material forming the outer periphery of the charging means.

[0085] This allows negatively charged objects to be collected with high accuracy, for example, negatively charged toner T, to be collected with high accuracy. (Item 5) 4. The cleaning device according to any one of items 1 to 3, wherein in a triboelectric series, a material forming the outer periphery of the collection means is more likely to be negatively charged than a material forming the outer periphery of the collection means, and the material forming the outer periphery of the collection means is more likely to be negatively charged than a material forming the outer periphery of the charging means.

[0086] As a result, the positively charged objects to be collected can be collected with high accuracy. For example, the positively charged toner T or dust H can be collected with high accuracy. (Item 6) 6. The cleaning device according to any one of items 1 to 5, wherein the speed at which the peripheral surface of the recovery means moves is faster than the speed at which the peripheral surface of the collection means moves.

[0087] This will improve the transfer of the collected matter from the collection roller 21 to the recovery roller 26. (Item 7) 7. The cleaning device according to any one of items 1 to 6, wherein an angle formed by a first line connecting the rotation center of the collection means and the rotation center of the charging means and a second line connecting the rotation center of the collection means and the rotation center of the recovery means is smaller than 90° and is equal to or greater than 30°.

[0088] As shown in FIG. 11, the dust H2 knocked off the collecting roller 21 by the charging roller 22 will tend to head toward the collecting roller 26. (Item 8) 8. The cleaning device according to any one of items 1 to 7, further comprising a charge eliminating means for eliminating electricity from a surface of the charging means.

[0089] The charge removing sheet 23 is an example of a charge removing means for removing electricity from the surface of the charging roller 22. This improves the charging performance of the charging roller 22, and allows the collecting roller 21 to be sufficiently charged. (Item 9) 9. The cleaning device according to claim 8, wherein the static electricity removing means has a grounded conductive plate or sheet.

[0090] The static elimination sheet 23 is an example of a grounded conductive plate or sheet. (Item 10) Item 1 to Item 2 further include a guide member provided between the charging means and the collecting means for guiding the objects to be collected to the collecting means. 10. A cleaning device as described in any one of claims 9 to 9.

[0091] 12, the guide plate 120 is an example of a guide member that is provided between the charging roller 22 and the collection roller 26 and guides the collected materials to the collection roller 26. This will make it even easier for the collected materials to be guided to the collection roller 26. (Item 11) 11. The cleaning device according to any one of items 1 to 10, wherein the surface to be cleaned is a peripheral surface of an intermediate transfer body provided in an image forming apparatus.

[0092] The peripheral surface of the intermediate transfer belt 7 is an example of a surface to be cleaned. (Item 12) 11. The cleaning device according to any one of items 1 to 10, wherein the surface to be cleaned is a transfer material transport body that transports a peripheral surface of a transfer material in an image forming apparatus. (Item 13) 11. The cleaning device according to any one of items 1 to 10, wherein the surface to be cleaned is a peripheral surface of an image carrier provided in an image forming apparatus.

[0093] As shown in FIG. 6, the peripheral surface of the photosensitive drum 1 is an example of a surface to be cleaned. (Item 14) 11. The cleaning device according to any one of items 1 to 10, wherein the surface to be cleaned is a surface of a transfer material on which an image is formed in an image forming apparatus.

[0094] As described with reference to FIG. 8, the surface of the sheet P (the surface on which an image is formed) is an example of a surface to be cleaned. (Item 15) 11. The cleaning device according to any one of items 1 to 10, wherein the surface to be cleaned is a surface of a glass substrate for a display. (Item 16) 11. The cleaning apparatus according to any one of claims 1 to 10, wherein the surface to be cleaned is a surface of a semiconductor wafer. (Item 17) 11. The cleaning device according to any one of claims 1 to 10, wherein the surface to be cleaned is a surface of an electrostatic adsorption stage provided in a semiconductor manufacturing device. (Item 18) Item 18. The cleaning device according to any one of items 1 to 17, wherein the collected matter is dust. (Item 19) an image forming means for forming an image on a sheet; a rotatable collecting means for collecting objects on the sheet or the surface of the image forming means to be cleaned by electrostatic charging; an electrifying means that rotates while in contact with the collecting means and frictionally electrifies the circumferential surface of the collecting means; a collecting means that rotates while in contact with the collecting means and collects the objects to be collected that are attached to the circumferential surface of the collecting means, In the rotation direction of the collection means, the collection means and the surface to be cleaned are in contact with each other at a first position, In the rotation direction of the collection means, the collection means and the recovery means are in contact with each other at a second position, the collecting means and the charging means are in contact with each other at a third position in the rotation direction of the collecting means, the first position, the second position, and the third position are arranged in order along the rotation direction of the collection means, the rotation direction of the collecting means is the same as the rotation direction of the charging means, The image forming apparatus, wherein the rotation direction of the collecting means is opposite to the rotation direction of the recovery means.

[0095] The intermediate transfer belt 7 and the photosensitive drum 1 are an example of an image forming unit. The circumferential surfaces of the intermediate transfer belt 7 and the photosensitive drum 1 are an example of surfaces of the image forming unit to be cleaned. (Item 20) A conveying means for conveying a sheet; a first cleaning means for cleaning the sheet; an image forming means for forming an image on the sheet cleaned by the first cleaning means; a second cleaning unit for cleaning the image forming unit, The first cleaning means is a rotatable first collecting means for collecting objects on the sheet by electrostatic charge; a first charging means that rotates while in contact with the first collecting means and frictionally charges a peripheral surface of the first collecting means; a first collecting means that rotates while being in contact with the first collecting means and collects the objects to be collected that are attached to the circumferential surface of the first collecting means, In a rotation direction of the first collecting means, the first collecting means and the sheet are in contact with each other at a first position, In the rotation direction of the first collecting means, the first collecting means and the first recovering means are in contact with each other at a second position, the first collecting means and the first charging means are in contact with each other at a third position in the rotation direction of the first collecting means, the first position, the second position, and the third position are arranged in order along the rotation direction of the first collection means, the rotation direction of the first collecting means is the same as the rotation direction of the first charging means, the rotation direction of the first collecting means is opposite to the rotation direction of the first recovering means; The second cleaning means is a rotatable second collecting means for collecting objects on a surface to be cleaned of the image forming means by electrostatic charge; a second charging means that rotates while in contact with the second collecting means and frictionally charges the circumferential surface of the second collecting means; a second collecting means that rotates while in contact with the second collecting means and collects the objects to be collected that are attached to the circumferential surface of the second collecting means, In the rotation direction of the second collection means, the second collection means and the surface to be cleaned are in contact with each other at a fourth position, In the rotation direction of the second collection means, the second collection means and the second recovery means are in contact with each other at a fifth position, the second collecting means and the second charging means are in contact with each other at a sixth position in the rotation direction of the second collecting means, the fourth position, the fifth position, and the sixth position are arranged in order along the rotation direction of the second collection means, the rotation direction of the second collecting means is the same as the rotation direction of the second charging means, an image forming apparatus, wherein the rotation direction of the second collecting means is opposite to the rotation direction of the second recovering means;

[0096] As shown in Figure 8, the cleaning device 80 is an example of the first cleaning means. As shown in Figures 2 and 6, the cleaning device 20 is an example of the second cleaning means. (Item 21) A rotatable collecting means for electrostatically collecting objects on a surface to be cleaned; an electrifying means that contacts the collecting means and frictionally electrifies the peripheral surface of the collecting means; a collecting means that rotates while in contact with the collecting means and collects the objects to be collected that are attached to the circumferential surface of the collecting means, In the rotation direction of the collection means, the collection means and the surface to be cleaned are in contact with each other at a first position, In the rotation direction of the collection means, the collection means and the recovery means are in contact with each other at a second position, the collecting means and the charging means are in contact with each other at a third position in the rotation direction of the collecting means, The charge polarity of the object to be collected is a first polarity, a cleaning device, wherein in a triboelectric series, the material of the collection means is a material that is more easily charged to a second polarity than the material of the charging means, and the material of the recovery means is a material that is more easily charged to the second polarity than the material of the collection means.

[0097] This makes it possible to collect the objects to be collected with a simpler configuration.

[0098] The invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0099] 21...collection roller, 22...charging roller, 26...recovery roller

Claims

1. A rotatable collecting means for electrostatically collecting objects on a surface to be cleaned; an electrifying means that rotates while in contact with the collecting means and frictionally electrifies the circumferential surface of the collecting means; a collecting means that rotates while in contact with the collecting means and collects the objects to be collected that are attached to the circumferential surface of the collecting means, In the rotation direction of the collection means, the collection means and the surface to be cleaned are in contact with each other at a first position, In the rotation direction of the collection means, the collection means and the recovery means are in contact with each other at a second position, the collecting means and the charging means are in contact with each other at a third position in the rotation direction of the collecting means, the first position, the second position, and the third position are arranged in order along the rotation direction of the collection means, the rotation direction of the collecting means is the same as the rotation direction of the charging means, A cleaning apparatus, wherein the direction of rotation of the collecting means is opposite to the direction of rotation of the recovery means.

2. 2. The cleaning device according to claim 1, wherein the collecting means comprises a collecting brush and a rotating shaft on which the collecting brush is provided.

3. 2. The cleaning device according to claim 1, wherein the charging means comprises a charging brush and a rotating shaft on which the charging brush is provided.

4. 2. The cleaning device of claim 1, wherein in a triboelectric series, a material forming the outer periphery of the collection means is more likely to be positively charged than a material forming the outer periphery of the collection means, and the material forming the outer periphery of the collection means is more likely to be positively charged than a material forming the outer periphery of the charging means.

5. 2. The cleaning device of claim 1, wherein in a triboelectric series, a material forming an outer periphery of the collection means is more likely to be negatively charged than a material forming an outer periphery of the collection means, and the material forming the outer periphery of the collection means is more likely to be negatively charged than a material forming the outer periphery of the charging means.

6. The cleaning device according to claim 1 , wherein a moving speed of the peripheral surface of the recovery means is faster than a moving speed of the peripheral surface of the collection means.

7. 2. The cleaning device according to claim 1, wherein an angle formed by a first line connecting the rotation center of the collecting means and the rotation center of the charging means and a second line connecting the rotation center of the collecting means and the rotation center of the recovery means is smaller than 90° and greater than or equal to 30°.

8. 2. The cleaning device according to claim 1, further comprising a charge eliminating means for eliminating electricity from a surface of said charging means.

9. 9. The cleaning device according to claim 8, wherein the static electricity removing means comprises a grounded conductive plate or sheet.

10. 2. The cleaning device according to claim 1, further comprising a guide member provided between the charging means and the collecting means for guiding the collected materials to the collecting means.

11. The cleaning device according to claim 1 , wherein the surface to be cleaned is a peripheral surface of an intermediate transfer body provided in an image forming apparatus.

12. The cleaning device according to claim 1 , wherein the surface to be cleaned is a peripheral surface of a transfer material transport body that transports a transfer material in an image forming apparatus.

13. The cleaning device according to claim 1 , wherein the surface to be cleaned is a peripheral surface of an image carrier provided in an image forming apparatus.

14. The cleaning device according to claim 1 , wherein the surface to be cleaned is a surface of a transfer material on which an image is formed in an image forming apparatus.

15. The cleaning device according to claim 1 , wherein the surface to be cleaned is a surface of a glass substrate for a display.

16. 11. The cleaning apparatus of claim 1, wherein the surface to be cleaned is a surface of a semiconductor wafer.

17. The cleaning device according to claim 1 , wherein the surface to be cleaned is a surface of an electrostatic attraction stage provided in a semiconductor manufacturing device.

18. The cleaning device according to claim 1 , wherein the collected matter is dust.

19. an image forming means for forming an image on a sheet; a rotatable collecting means for collecting objects on the sheet or the surface of the image forming means to be cleaned by electrostatic charging; an electrifying means that rotates while in contact with the collecting means and frictionally electrifies the circumferential surface of the collecting means; a collecting means that rotates while in contact with the collecting means and collects the objects to be collected that are attached to the circumferential surface of the collecting means, In the rotation direction of the collection means, the collection means and the surface to be cleaned are in contact with each other at a first position, In the rotation direction of the collection means, the collection means and the recovery means are in contact with each other at a second position, the collecting means and the charging means are in contact with each other at a third position in the rotation direction of the collecting means, the first position, the second position, and the third position are arranged in order along the rotation direction of the collection means, the rotation direction of the collecting means is the same as the rotation direction of the charging means, The image forming apparatus, wherein the rotation direction of the collecting means is opposite to the rotation direction of the recovery means.

20. A conveying means for conveying a sheet; a first cleaning means for cleaning the sheet; an image forming means for forming an image on the sheet cleaned by the first cleaning means; a second cleaning unit for cleaning the image forming unit, The first cleaning means is a rotatable first collecting means for collecting objects on the sheet by electrostatic charge; a first charging means that rotates while in contact with the first collecting means and frictionally charges a peripheral surface of the first collecting means; a first collecting means that rotates while in contact with the first collecting means and collects the objects to be collected that are attached to the circumferential surface of the first collecting means, In a rotation direction of the first collecting means, the first collecting means and the sheet are in contact with each other at a first position, In the rotation direction of the first collecting means, the first collecting means and the first recovering means are in contact with each other at a second position, the first collecting means and the first charging means are in contact with each other at a third position in the rotation direction of the first collecting means, the first position, the second position, and the third position are arranged in order along the rotation direction of the first collection means, the rotation direction of the first collecting means is the same as the rotation direction of the first charging means, the rotation direction of the first collecting means is opposite to the rotation direction of the first recovering means; The second cleaning means is a rotatable second collecting means for collecting objects on a surface to be cleaned of the image forming means by electrostatic charge; a second charging means that rotates while in contact with the second collecting means and frictionally charges a peripheral surface of the second collecting means; a second collecting means that rotates while in contact with the second collecting means and collects the objects to be collected that are attached to the circumferential surface of the second collecting means, In the rotation direction of the second collection means, the second collection means and the surface to be cleaned are in contact with each other at a fourth position, In the rotation direction of the second collection means, the second collection means and the second recovery means are in contact with each other at a fifth position, the second collecting means and the second charging means are in contact with each other at a sixth position in the rotation direction of the second collecting means, the fourth position, the fifth position, and the sixth position are arranged in order along the rotation direction of the second collection means, the rotation direction of the second collecting means is the same as the rotation direction of the second charging means, an image forming apparatus, wherein the rotation direction of the second collecting means is opposite to the rotation direction of the second recovering means;

21. A rotatable collecting means for electrostatically collecting objects on a surface to be cleaned; an electrifying means that contacts the collecting means and frictionally electrifies the peripheral surface of the collecting means; a collecting means that rotates while in contact with the collecting means and collects the objects to be collected that are attached to the circumferential surface of the collecting means, In the rotation direction of the collection means, the collection means and the surface to be cleaned are in contact with each other at a first position, In the rotation direction of the collection means, the collection means and the recovery means are in contact with each other at a second position, the collecting means and the charging means are in contact with each other at a third position in the rotation direction of the collecting means, The charge polarity of the object to be collected is a first polarity, a cleaning device, wherein in a triboelectric series, the material of the collection means is a material that is more easily charged to a second polarity than the material of the charging means, and the material of the recovery means is a material that is more easily charged to the second polarity than the material of the collection means.

Images