JPH09197929A - Cleaning device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning device for preventing the damage of a cleaning roller. SOLUTION: The cleaning device 21 is provided with a 1st cleaning means which is installed so as to be rotated in contact with an image carrier and for removing developer sticking on to the image carrier and for cleaning the surface of the image carrier, and a blade-shaped 2nd cleaning means arranged so that the blade end part may be separated from the 1st cleaning means and also the central area of the blade may come into contact with the 1st cleaning means and for removing the developer sticking to the 1st cleaning means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning device used in a copying machine, a printer or the like, that is, a device for removing and collecting a developer on the surface of an image bearing member such as a photoconductor. In particular, the present invention relates to a technique for performing a cleaning device for a photoconductor while removing the developer attached to the surface of the cleaning roller that contacts the photoconductor.

[0002]

2. Description of the Related Art Conventionally, there is a cleaning device in which a cleaning roller having an appropriate elasticity is arranged in pressure contact with a photosensitive member, and the rotation of the cleaning roller removes and collects toner and paper dust adhering to the photosensitive member surface. Are known.

Regarding the cleaning roller, Japanese Patent Publication No. 6-4
Japanese Patent No. 2114 discloses a technique in which a blade-shaped scraper is provided in contact with a cleaning roller, and the scraper removes paper dust and toner adhering to the surface of the cleaning roller.

However, conventionally, the scraper is arranged so that only the so-called edge of the tip of the scraper contacts the cleaning roller. Therefore, the contact pressure between the scraper and the cleaning roller becomes high, and there is a problem that the cleaning roller is rapidly worn or damaged. Further, when the cleaning roller is damaged, there is a problem that the cleaning of the photosensitive member by the cleaning roller is incomplete and the image quality is deteriorated.

[0005]

As described above, the conventional cleaning of the cleaning roller by the scraper has a problem that the cleaning roller is rapidly worn or damaged. It is an object of the present invention to eliminate the above-mentioned drawbacks and to provide a cleaning device that prevents damage to the cleaning roller. Another object of the present invention is to provide an image forming apparatus having a long-life cleaning roller and capable of forming a good image for a long period of time.

[0006]

In order to achieve the above object, a cleaning device and an image forming apparatus of the present invention are rotatably provided in contact with an image bearing member, and a developer adhered on the image bearing member. First to remove and clean the image carrier
And a blade shape, the blade end portion is spaced from the first cleaning means, and the central region is in contact with the first cleaning means, and is attached to the first cleaning means. Second cleaning means for removing the developer.

When the edge of the blade is in contact with the first cleaning means, there is a problem that the first cleaning means is damaged by the edge, but the central region of the blade, that is, the abdomen is firstly damaged.
The above-mentioned problem can be solved and the life of the first cleaning means can be extended by providing the cleaning means in contact with the cleaning means.
Particularly, by setting the contact width between the blade and the first cleaning means to be 2 to 5 mm, the developer and the like adhering to the first cleaning means can be removed well.

In order to achieve the above object, the cleaning device and the image forming apparatus of the present invention are rotatably provided in contact with the image bearing member to remove the developer adhering to the image bearing member to remove the image. First cleaning means for cleaning the top of the carrier,
The blade has a blade shape having a plurality of holes, the blade end is separated from the first cleaning means, and the central region has a contact width of 1 to 5 mm.
And a second cleaning unit which is provided so as to abut on the cleaning unit and removes the developer adhering to the first cleaning unit.

By abutting the second cleaning means against the first cleaning means with a belly pad, damage to the first cleaning means can be prevented. By providing the abdomen of the blade having a plurality of holes in contact with the first cleaning means, the developer adhering to the first cleaning means passes through the holes provided in the blade and
Be removed from the cleaning means.

Further, the cleaning device and the image forming apparatus of the present invention are rotatably provided in contact with the image carrier, remove the developer adhering to the image carrier, and clean the image carrier. The first cleaning means, a voltage applying means for applying a bias voltage having the same polarity as the charging polarity of the developer to the first cleaning means, a blade shape having a plurality of holes, and a blade end portion A second cleaning unit which is arranged so as to be separated from the first cleaning unit and whose central region abuts on the first cleaning unit, and which removes the developer adhering to the first cleaning unit.

By applying a bias voltage having the same polarity as the charge polarity of the developer to the first cleaning means, the first cleaning means removes minute developer and paper dust that are easily charged to the opposite polarity to the original charge polarity. Can be removed electrostatically. By bringing the abdomen of the blade-shaped second cleaning means into contact with the first cleaning means, it is possible to satisfactorily remove minute developer, paper dust and the like without damaging the first cleaning means. .

Furthermore, the cleaning device and the image forming apparatus of the present invention are rotatably provided in contact with the image carrier, remove the developer adhering to the image carrier, and clean the image carrier. While having a blade shape having a first cleaning means and a plurality of holes having a hole diameter of 300 μm or less,
The blade end is spaced from the first cleaning means and the central region is arranged to abut the first cleaning means,
Second cleaning means for removing the developer adhering to the first cleaning means; voltage applying means for applying a bias voltage having a polarity opposite to the charging polarity of the developer to the second cleaning means,
And a recycling unit for recycling the developer removed by the second cleaning unit as a developer for developing the electrostatic latent image again.

By bringing the abdomen of the blade-shaped second cleaning means into contact with the first cleaning means, it is possible to prevent the first cleaning means from being damaged. Further, by setting the size of the holes provided in the second cleaning means to 300 μm or less, the coarse particles formed by the agglomeration of the developer are not removed by the second cleaning means. Further, by applying a bias voltage having a polarity opposite to the charge polarity of the developer to the second cleaning means, the developer charged to a polarity opposite to the original charge polarity is not removed. Therefore, it is possible to remove the coarse powder and the developer charged to the opposite polarity to the original charging polarity, and collect only the recyclable developer by the second cleaning means.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of an image forming apparatus 1 which is an embodiment of the present invention. In FIG. 1, a photosensitive drum 3 as an image bearing member is rotatably provided in a direction indicated by an arrow a.

The following are arranged around the photosensitive drum 3 along the rotation direction. In FIG. 1, first, a charging charger 5 that uniformly charges the photosensitive drum 3 is provided so as to face the photosensitive drum 3.

Above the photosensitive drum 3, an original table 7 on which an original is placed and an exposure unit 9 for exposing the charged photosensitive drum 3 according to the original image to form an electrostatic latent image are provided. ing.

The exposure unit 9 includes an exposure lamp 11 which serves as a light source,
Reflection mirrors 13a, 13b, 13c, 13d, 13 that guide the light emitted from the exposure lamp 11 onto the photosensitive drum 3.
e, 13f, a slit glass 13g, and a lens unit 14 for forming an image of reflected light.

Toner T, which is a developer, and a carrier (not shown) are housed downstream of the exposure unit 9, and a developing device 15 for developing the electrostatic latent image formed by the exposure unit 9 with the toner T is stored.
Is provided. Downstream of the developing device 15, a transfer charger 17 for transferring the toner image formed by the developing device 15 on a sheet P as an image forming medium is provided.

Charging charger 5, exposure unit 9, developing unit 15
Constitutes a developer image forming means. Adjacent to the transfer charger 17, a peeling charger 19 for peeling the paper P electrostatically attached to the photosensitive drum 3 at the time of transfer is arranged. A cleaning device 21 for removing the toner T remaining on the photosensitive drum 3 after the transfer is provided downstream of the peeling charger 19. The cleaning device 21 has a cleaning blade 23 and a cleaning roller 25. The cleaning blade 23 scrapes off the toner T on the photosensitive drum 3, and the cleaning roller 25 collects the scraped toner T.
The cleaning roller 25 has a scraper 29 for removing the toner T adhering to the surface of the cleaning roller 25.
Is provided. This scraper 29 is closely related to the present invention, and the scraper 29 will be described later in detail together with the detailed structure of the cleaning device 21.

On the downstream side of the cleaning device 21, there is provided a static eliminator 31 for removing charges on the photosensitive drum 3. In FIG. 1, on the right side of the photoconductor drum 3, a paper feed cassette 33 for accommodating the paper P is detachably provided in the main body of the image forming apparatus 1. In addition, in the main body of the image forming apparatus 1,
A pickup roller 35 for taking out the paper P in the paper feed cassette 33 is attached. Further, a paper feed roller pair 37 is provided near the pickup roller 35 to separate and feed the paper P one by one.

An aligning roller pair 39 is provided upstream of the transfer charger 17 along the conveyance direction of the sheet P to feed the conveyed sheet P toward the photosensitive drum 3 at a predetermined timing. The aligning roller pair 39 nips and conveys the paper P, and supplies the paper P between the photosensitive drum 3 and the transfer charger 17.

Downstream of the transfer charger 17 along the conveying direction of the paper P, the above-mentioned peeling charger 19 and the paper P are provided.
A conveyor belt 4 that carries and conveys the toner to a fixing device 35 described later.
1 and a fixing device 43 as fixing means for fixing the toner image on the sheet P are provided.

The conveyor belt 41 is made of an insulating material, and is charged by the transfer charger 17 to electrostatically adsorb the charged paper P and conveys it toward the fixing device 43. The fixing device 43 has a pair of rollers including a heating roller 45 and a pressure roller 47. The toner image is fused and fixed on the paper P by rotating the heating roller 45 and the pressure roller 47 in the directions indicated by arrows c and d, respectively.

A discharge roller pair 49 for discharging the fixed paper P to the outside of the image forming apparatus 1 and a paper discharge tray 51 for receiving the discharged paper P are provided downstream of the fixing device 35 along the conveyance direction of the paper P. Is provided.

An image forming process in the image forming apparatus of this embodiment having the above-described configuration will be described. When the image formation start is instructed via an operation panel or the like (not shown), the photosensitive drum 3 starts rotating in the direction of arrow a in the figure.
The charging charger 5 uniformly charges the surface of the rotating photosensitive drum 3 to about -600V.

When the exposure lamp 11 irradiates the document placed on the document table 7 with light and moves, the exposure unit 9 exposes the charged photosensitive drum 3 according to the document image. That is, the exposure section 9 irradiates the area other than the image area to which the toner T adheres with light to form an electrostatic latent image.

The developing device 15 attaches the toner T charged in advance to about +15 μC / g to the electrostatic latent image to form a toner image. The paper P is taken out one by one from the paper feed cassette 33 by the rotation of the pickup roller 35 and the paper feed roller pair 37, and is supplied between the photosensitive drum 3 and the transfer charger 17 by the aligning roller pair 39.

The transfer charger 17 applies a negative charge to the back surface of the supplied paper P to transfer the toner image onto the paper P. The peeling charger 19 performs AC corona discharge to peel the paper P attached to the photosensitive drum 3 from the photosensitive drum 3 during transfer. The conveyance belt 41 conveys the peeled sheet P toward the fixing device 43.

The fixing device 43 heats and melts the toner image on the paper P to fix the toner image on the paper P. After that, the paper P is discharged onto the paper discharge tray 51 by the rotation of the discharge roller pair 49.

On the other hand, the photosensitive drum 3 is a cleaning device 2
1, after the toner T remaining after the transfer is removed,
The charge is removed by the charge remover 31. The charge removal by the charge remover 31 completes one cycle of the image forming process, and the photosensitive drum 3 is charged by the charging charger 5 again in the next image formation.

FIG. 2 shows a detailed sectional view of the cleaning device 21. The cleaning blade 23 is made of urethane rubber, and has one end fixed to the cleaning device 21 and the other end abutting the photosensitive drum 3.

A cleaning roller 25 having a diameter of 14 mm and having elasticity as a first cleaning means is arranged in contact with the photosensitive drum 3 upstream of the cleaning blade 23 along the rotation direction of the photosensitive drum 3. . The cleaning roller 25 includes a metal core body 53 and an elastic layer 55 formed on the outer periphery of the core body 53. The elastic layer 55 has a hole diameter of 10
It is made of urethane foam having many pores of about μm, and its volume resistance value is 10 ⁵ Ωcm. Cleaning roller 2
5 has a contact width of about 3 along the rotation direction of the photosensitive drum 3.
It is arranged in pressure contact with the photosensitive drum so as to form a nip N ₁ of mm.

The cleaning roller 25 is provided with a blade-shaped scraper 27 as a second cleaning means for removing the toner T adhering to the surface of the cleaning roller 25. The scraper 27 has a thickness of 0.1
A large number of holes H having a diameter of about 1 mm are formed as shown in FIG. As shown in FIG. 4, the scraper 27 is arranged parallel to the direction of gravity so as to form a nip N _{2 of} about 2 mm between the scraper 27 and the cleaning roller 25. What contributes to the formation of the nip N ₂ is a region near the central region of the scraper 27, which is indicated by a chain line in FIG.
That is, the abdomen C. A so-called edge E at the end of the scraper 27 is separated from the cleaning roller 25.

The cleaning device 21 includes a scraper 27.
An accommodating portion 61 for accommodating the toner T, paper dust, and the like removed by the above is formed. The accommodating portion 61 is provided with a recovery auger 63 for conveying the toner T, paper dust, and the like accumulated in the accommodating portion to a not-shown discharged toner box.

The cleaning device 2 is provided upstream of the cleaning roller 25 along the rotation direction of the photosensitive drum 3.
A recovery blade 65 for preventing the toner T from spilling from No. 1 is attached to the cleaning device 21.

The cleaning device 2 thus constructed
In No. 1, the cleaning roller 25 slidably contacts the surface of the photosensitive drum 3 to remove the paper dust and the toner T adhering to the surface of the photosensitive drum 3 after transfer. However, the cleaning force by the cleaning roller 25 is not so great, and most of the toner T on the photosensitive drum 3 remains on the photosensitive drum 3 without being removed by the cleaning roller 25. The remaining toner T is removed by the cleaning blade 2
The photosensitive drum 3 rotating at 5 is scraped and removed. The toner T scraped off falls on the cleaning roller 25 or in the vicinity of the cleaning roller 25, and is collected by the cleaning roller 25.

As described above, the cleaning roller 25 is either collected by the sliding contact rotation of the cleaning roller 25 or scraped off by the cleaning blade 23.
The toner T and the paper dust that have dropped onto the cleaning roller 25 are removed by the scraper 27.

That is, as shown in FIG. 4, the toner T and the paper dust accumulated on the cleaning roller 25 come into contact with the scraper 27 as the cleaning roller 25 rotates, and pass through the holes H provided in the scraper 27. It is discharged into the accommodation portion 61. The recovery auger 63 conveys the toner T and the paper dust stored in the storage portion 61 to the discharged toner box (not shown).

When the image forming apparatus 1 provided with the cleaning device 21 as described above forms an image about 10,000 times,
The cleaning roller 25 was neither damaged nor permanently deformed.

That is, in this embodiment, the abdomen C of the scraper 27 is about 3 mm with respect to the cleaning roller 25.
The cleaning roller 2
No local load is applied to 5. For this reason, it is possible to prevent the cleaning roller 25, which is an elastic rubber roller, from being deformed or from causing permanent distortion during repeated image formation. Compared with the case where only the edge E of the scraper 27 abuts on the cleaning roller 25, when the abdomen C of the scraper abuts on the cleaning roller 25, the scraper 2 extends across the rotation axis direction of the photosensitive drum 3.
7 can be brought into stable contact, and scraping can be performed reliably.

For comparison, in the cleaning device 21 shown in FIG. 2, only the edge E of the scraper 27 contacts the cleaning roller 25 as shown in FIG.
The scraper 27 was arranged to form an image. In this case, the edge E bites into the cleaning roller 25 as shown in FIG. 6 when the image is formed about 10,000 times, and the cleaning roller 25 is permanently deformed. For this reason, the cleaning of the photosensitive drum 3 by the cleaning roller 25 is incomplete, and black spots appear on the image. As can be seen from this comparative example, the conventional cleaning failure of the photosensitive drum is caused by the edge of the scraper 27 being in contact with the cleaning roller 25. Therefore, in the above-described embodiment, the scraper 2
The abdomen, not the edge E of 7, contacts the cleaning roller 25. In order to bring the abdomen C of the scraper 27 into contact, the scraper 27 may be wound around the cleaning roller 25 as shown in FIG.

Even when the scraper 27 is arranged in this way, the cleaning roller 25 can be prevented from being damaged and the photosensitive drum 3 can be cleaned well. In the above embodiment, the scraper 27 has a large number of holes H.
Although the holes H are provided, the holes H are for facilitating the recovery of the toner T and the paper powder on the cleaning roller 25 into the containing portion 61, and the number of the holes H is not particularly limited.

The shape of the hole H is not particularly limited, either.
Even if the shape is not a perfect circle, various shapes such as a quadrangle and a triangle can be applied as shown in FIGS. However, scraper 2
In consideration of the strength of No. 7, the recovery efficiency of toner T, etc., the nip N ₂
In the area of the hole H so that the porosity is 40 to 70%.
Is preferably formed.

The cleaning at the nip N ₂ roller 2
The contact width between the scraper 5 and the scraper 27 is preferably 2 to 5 mm.
12 to 14 show the cleaning state of the photoconductor drum 3 and 10,000 times of image formation when the contact width between the cleaning roller 25 and the scraper 27 is 1, 2, 3, 4, 5, 6, 7 mm. Cleaning roller 25 at the time of performing
The results obtained by examining the presence or absence of damage of the are shown. As the cleaning roller 25, those having diameters of 12 mm, 14 mm, and 20 mm were prepared, and evaluation was performed for the case where each cleaning roller 25 was used. When the contact width is 6 mm or more, the contact area of the scraper 27 becomes too large, so that the cleaning roller 25 is permanently deformed. Further, when the contact width is 1 mm, it may not be possible to perform sufficient cleaning.

Therefore, in the case of the practically used cleaning roller 25 having a diameter of about 12 to 20 μm, the contact width is set to 2 to 5 mm to prevent damage to the cleaning roller 25 and perform good cleaning. You can say that you can. In the experiment, particularly when the contact width is 2 to 3 mm, good cleaning can be performed.

Next, another embodiment of the present invention will be described. Other embodiments described below differ from the first embodiment in the configuration of the cleaning device 1. That is, also in the embodiment described below, the overall configuration of the image forming apparatus 1 is the same as that of the first embodiment, and the same parts as those of the first embodiment are designated by the same reference numerals and the description thereof is omitted.

FIG. 15 shows a second embodiment of the present invention.
The cleaning device 67 includes the cleaning blade 6 arranged around the photosensitive drum 3 as in the above-described embodiment.
9 and a cleaning roller 71. The materials, positions and the like of the cleaning blade 69 and the cleaning roller 71 are the same as those in the above-described embodiment, and will not be repeated here. Further, the point that the scraper 77 is provided in contact with the cleaning roller 71, the point that the cleaning device 67 has the accommodating portion 79, the recovery auger 81, and the recovery blade 83 are the same as in the first embodiment. Is.

The cleaning roller 71 is a metal core body 8.
5 and an elastic layer 87 formed around the core body 85, and the core body 85 is connected to a positive DC power source 89. On the other hand, the photoconductor drum 3 and the scraper 77 are grounded. A bias voltage of +300 V having the same polarity as the charging polarity of the toner T is applied to the core body 85 from the power source 89.

By the way, in addition to the toner T, negatively charged paper powder, wax, etc. remain on the photosensitive drum 3 after the transfer. Further, among the toner T, fine particles having a particle size of 5 μm or less easily cause unstable charging,
Some are negatively charged. It is difficult to scrape off such minute toner and paper dust with the cleaning blade 69.

Therefore, in the cleaning device shown in FIG. 15, the residual toner T is removed by the cleaning blade 69, and the negatively charged fine toner and paper dust are applied to the cleaning roller 71 with a positive bias voltage, whereby the cleaning roller is cleaned. At 71, the sliding contact is removed electrically and mechanically. Then, the toner T and the paper powder collected by the cleaning roller 71 are scraped off by the scraper 77 and collected in the accommodating portion 79.

When the photosensitive drum 3 was cleaned by the cleaning device 21 shown in FIG. 15, the efficiency of collecting paper dust and fine toner was improved. The third embodiment will be described with reference to FIG.

The present embodiment is characterized in that means is provided for selecting the toner T removed from the photosensitive drum 3 and recycling it again as developing toner. FIG. 16 is a sectional view of the cleaning device 91 according to the third embodiment.

Like the cleaning device 21, the cleaning device 91 has a cleaning blade 93 made of urethane rubber. Further, a cleaning roller 95 having elasticity is provided downstream of the cleaning blade 93 along the rotation direction of the photosensitive drum 3 so as to be rotatable in the direction of arrow e in the figure. The cleaning roller 95 is the core body 9.
7 and an elastic layer 99 formed on the outer periphery of the core body 97. Like the cleaning roller 25, the elastic layer 99 is made of urethane foam having a large number of holes with a diameter of about 10 μm. The core body 97 is grounded. The cleaning roller 95 is provided in pressure contact with the photoconductor drum 3 so as to form a nip N ₃ having a length of 3 mm between the cleaning roller 95 and the photoconductor drum 3.

The cleaning roller 95 has a thickness of 0.1.
A blade-shaped scraper 101 of mm is provided so as to abut. The cleaning roller 95 has a scraper 101.
Of the scraper 101 is in contact with the cleaning roller 95, and the end portion of the scraper 101 is separated from the cleaning roller 95. A large number of holes H having a diameter of 200 μm are formed in the scraper 101. The scraper 101 is made of SUS and has conductivity. The scraper 101 is connected to the negative DC power supply 103, and a bias voltage of −500 V is applied to the scraper 101.

Along the rotation direction of the cleaning roller 95, downstream of the abutting position of the scraper 101 and the cleaning roller 95, the foreign matter is recovered which collects what remains on the cleaning roller 95 without being removed by the scraper 101. A box 105 is provided. The foreign matter collection box 105 is a storage unit 1 for storing the collected matter.
07. Further, the foreign matter collection box 105 holds the foreign matter provided in the storage portion 87 facing the cleaning roller 75 with a gap of 1.5 mm from the cleaning roller 95.
It has a guide part 109 for guiding to.

On the other hand, the cleaning device 91 is provided with an accommodating portion 111 for accommodating the toner T removed by the scraper 101. A recovery auger 113 for returning the stored toner T to the developing device 15 and recycling it again as a developer is provided in the storage portion 111.

The cleaning device 9 configured as described above
The cleaning process No. 1 will be described. Following the rotation of the photosensitive drum 3, the cleaning roller 95 rotates in the direction of arrow e in the figure. The cleaning roller 95 is in sliding contact with the surface of the photosensitive drum 3 and the toner T on the surface of the photosensitive drum 3
And remove paper dust. However, the cleaning power of the cleaning roller 95 is not so large, and most of the toner T remains on the photosensitive drum 3 without being removed by the cleaning roller 95.

The cleaning blade 93 removes the remaining toner T from the photosensitive drum 3 rotating in the direction of arrow a in the figure.
Scrape from. The toner T scraped off falls on the cleaning roller 95, and the toner T and paper dust are collected on the cleaning roller 95.

By the way, among the toners cleaned and removed from the photoconductor drum 3, there are the residual toner T after transfer, paper dust and the like as described above, and the fine toner T and paper dust whose inner particle diameter is 5 μm or less are It is electrically unstable. Originally, the toner T is
Even after the transfer, the positive charge held at the time of development is held. However, the electrically unstable fine powder toner T retains a negative charge having a polarity opposite to that which it should have, or combines with a positive charge to form an aggregate.

Toner T having such a negative charge
If all of the residual toner T containing paper dust and aggregates is collected, the collected toner T cannot be recycled as it is as a developer.

Therefore, in this embodiment, a bias voltage of -500 V is applied to the scraper 101 provided with a large number of holes H of 200 μm in order to selectively collect and recover the toner T used as the developer again. Since the electrostatic repulsive force acts between the scraper 101 to which the negative bias voltage is applied and the negatively charged toner T, the negatively charged toner T cannot pass through the hole H. The size of the hole H of the scraper 101 is 200 μm.
Therefore, the coarse powder formed by the aggregation of the toner T cannot pass through the holes H. In this way, the toner T having a negative charge and the residual toner T from which the coarse powder has been removed pass through the hole H of the scraper 101 and are collected in the containing portion 111. The toner T collected in the containing portion 111 is conveyed to the developing device 15 by the rotation of the collecting auger 113 so as to be used again as a developer.

On the other hand, without being removed by the scraper 101,
The negative toner T and the coarse powder remaining on the cleaning roller 95 are guided by the guide portion 109 by the rotation of the cleaning roller 95 and collected in the accommodating portion 107.

As described above, in this embodiment, the reusable recycled toner T can be selectively collected by the scraper 101. The size of the holes H provided in the scraper 101 is preferably 300 μm or less. In FIG. 17, the diameter of the hole H is 100, 200, 300, 50.
The results of examining the occurrence status of black spots in the image for each case of 0,800 μm are shown. The number of black spots generated was 5,000 times consecutively, and then A3 paper 1
It is defined as the number of black dots generated per sheet. In FIG. 17, the horizontal axis represents the size of the hole diameter, and the vertical axis represents the number of black dots generated, showing the relationship between the two. As can be seen from FIG. 17, the hole diameter is 300μ
When it exceeds m, many black spots are generated, and when it is 300 μm or less, almost no black spots are observed. Therefore, it was found that the recycled toner can be efficiently collected by setting the hole diameter provided in the scraper 81 to 300 μm or less.

Although some embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and can be freely modified without departing from the spirit of the present invention.

For example, although elastic foaming rollers are used as the cleaning roller 25 and the cleaning roller 95, a fur brush in which acrylic fibers are bundled at about 5000 fibers / inch ₂ can also be used as a hair body. By bringing the scraper into contact with the fur brush, the fur brush surface can be cleaned without causing breakage of the hair.

[0066]

As described above, according to the present invention, it is possible to prevent the cleaning roller from being damaged when removing the toner T and the paper powder adhering to the surface of the cleaning roller. Therefore, the life of the cleaning roller can be extended. Further, since the cleaning roller is prevented from being damaged, the photoconductor can be sufficiently cleaned and a good image can be formed for a long period of time.

[Brief description of drawings]

FIG. 1 is a sectional view of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the cleaning device according to the first embodiment of the present invention.

FIG. 3 is a diagram illustrating a second cleaning unit according to the first exemplary embodiment.

FIG. 4 is an enlarged cross-sectional view of a main part of the cleaning device according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating a main part of a cleaning device according to a comparative example.

FIG. 6 is a diagram illustrating a main part of a cleaning device according to a comparative example.

FIG. 7 is a modified example of the cleaning device according to the first embodiment.

FIG. 8 is a diagram illustrating an example of a second cleaning unit according to the first exemplary embodiment.

FIG. 9 is a diagram illustrating an example of a second cleaning unit according to the first exemplary embodiment.

FIG. 10 is a diagram illustrating an example of a second cleaning unit according to the first exemplary embodiment.

FIG. 11 is a diagram illustrating an example of a second cleaning unit according to the first exemplary embodiment.

FIG. 12 is a diagram showing a change in the cleaning state of the surface of the image carrier and the presence / absence of damage to the first cleaning unit when the contact width between the second cleaning unit and the first cleaning unit changes. .

FIG. 13 is a diagram showing a change in the cleaning state of the surface of the image carrier and the presence / absence of damage to the first cleaning unit when the contact width between the second cleaning unit and the first cleaning unit changes. .

FIG. 14 is a diagram showing a change in the cleaning state of the surface of the image carrier and the presence / absence of damage to the first cleaning unit when the contact width between the second cleaning unit and the first cleaning unit changes. .

FIG. 15 is a cross-sectional view of a cleaning device according to a second embodiment.

FIG. 16 is a sectional view of a cleaning device according to a third embodiment.

FIG. 17 is a diagram showing the relationship between the size of holes provided in the second cleaning unit and the number of black dots generated in an image.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image forming apparatus 5 Charger charger 9 Exposure part 15 Developing device 21,67,91 Cleaning device 23,69,93 Cleaning blade 25,71,95 Cleaning roller 27,77,101 Scraper 61,79,111 Storage part 63,81 , 113 Recovery auger

Claims (10)

[Claims] 1. A first cleaning unit, which is rotatably provided in contact with an image carrier, removes a developer adhering to the image carrier, and cleans the image carrier, and has a blade shape. At the same time, the blade end portion is arranged so as to be separated from the first cleaning means, and the central region thereof is brought into contact with the first cleaning means, so as to remove the developer adhering to the first cleaning means. A cleaning device comprising: a cleaning unit. 2. A first cleaning unit, which is rotatably provided in contact with the image carrier, removes the developer adhering to the image carrier, and cleans the image carrier, and has a blade shape. At the same time, the blade end is separated from the first cleaning means, and the central region has a contact width of 1
A cleaning means, which is provided so as to be in contact with the first cleaning means so as to have a size of ˜5 mm, and has a second cleaning means for removing the developer adhering to the first cleaning means. apparatus. 3. A first cleaning unit, which is rotatably provided in contact with the image carrier, removes the developer adhering to the image carrier, and cleans the image carrier, and a plurality of holes. A developer that has a blade shape and that is arranged such that the blade end is separated from the first cleaning means and the central region is in contact with the first cleaning means, and that is attached to the first cleaning means. And a second cleaning means for removing the. 4. A first cleaning unit that is rotatably provided in contact with the image carrier to remove the developer adhering to the image carrier and clean the image carrier; A voltage applying means for applying a bias voltage of the same polarity as the charging polarity to the first cleaning means, and a blade shape having a plurality of holes, and a blade end part thereof separated from the first cleaning means, and A cleaning device, wherein a central region is arranged so as to abut the first cleaning means, and the second cleaning means removes the developer adhering to the first cleaning means. 5. A first cleaning unit which is rotatably provided in contact with the image carrier and removes the developer adhering to the image carrier and cleans the image carrier, and a hole diameter of 300 μm or less. A blade shape having a plurality of holes, the blade end is spaced from the first cleaning means, and the central region is in contact with the first cleaning means. Second cleaning means for removing the developer adhering to the toner; voltage applying means for applying a bias voltage having a polarity opposite to the charging polarity of the developer to the second cleaning means; and removal by the second cleaning means. And a recycling means for recycling the developed developer as a developer for developing the electrostatic latent image again. 6. A developer image forming means for developing an electrostatic latent image formed on an image bearing member to form a developer image, and the developer image formed on the image bearing member as an image forming medium. A transfer unit for transferring the image onto the image carrier, and a first cleaning unit rotatably provided in contact with the image carrier to remove the developer remaining on the image carrier and clean the image carrier. , Having a blade shape, and having a blade end portion spaced apart from the first cleaning means and a central region abutting the first cleaning means, the developer attached to the first cleaning means An image forming apparatus comprising: a second cleaning unit that removes the second cleaning unit. 7. A developer image forming means for developing an electrostatic latent image formed on an image carrier to form a developer image, and a medium for forming an image on the developer image formed on the image carrier. A transfer unit for transferring the image onto the image carrier, and a first cleaning unit rotatably provided in contact with the image carrier to remove the developer remaining on the image carrier and clean the image carrier. Having a blade shape, separating the blade end from the first cleaning means, and having a contact width of 1 in the central region
An image having a second cleaning unit that is provided so as to be in contact with the first cleaning unit so as to have a size of ˜5 mm, and that removes the developer adhering to the first cleaning unit. Forming equipment. 8. A developer image forming means for developing an electrostatic latent image formed on an image carrier to form a developer image, and the developer image formed on the image carrier as an image forming medium. A transfer unit for transferring the image onto the image carrier, and a first cleaning unit rotatably provided in contact with the image carrier to remove the developer remaining on the image carrier and clean the image carrier. A blade shape having a plurality of holes, the blade end portion being spaced apart from the first cleaning means, and the central region being in contact with the first cleaning means, the first cleaning means An image forming apparatus, comprising: a second cleaning unit that removes the developer attached to the. 9. A developer image forming means for developing an electrostatic latent image formed on an image carrier to form a developer image, and the developer image formed on the image carrier as an image forming medium. A transfer unit for transferring the image onto the image carrier, and a first cleaning unit rotatably provided in contact with the image carrier to remove the developer remaining on the image carrier and clean the image carrier. A voltage applying unit for applying a bias voltage having the same polarity as the charging polarity of the developer to the first cleaning unit, and a blade shape having a plurality of holes, and a blade end portion of the first cleaning unit. And a second cleaning unit that is disposed so as to be separated from the first cleaning unit and has a central region in contact with the first cleaning unit and that removes the developer adhering to the first cleaning unit. apparatus. 10. A developer image forming unit that develops an electrostatic latent image formed on an image carrier to form a developer image, and a medium on which the developer image formed on the image carrier is formed. A transfer unit for transferring the image onto the image carrier, and a first cleaning unit rotatably provided in contact with the image carrier to remove the developer remaining on the image carrier and clean the image carrier. A blade shape having a plurality of holes each having a hole diameter of 300 μm or less, the blade end portion being separated from the first cleaning means, and the central region being in contact with the first cleaning means, Second cleaning means for removing the developer adhering to the first cleaning means; voltage applying means for applying to the second cleaning means a bias voltage having a polarity opposite to the charging polarity of the developer; Of the developer removed by the cleaning means of the electrostatic latent image An image forming apparatus; and a recycling means for recycling as a developer for developing.