JPH0822231A - Electrophotographic equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an electrophotographic apparatus which is capable of obtaining a stable cleaning action for a long period of time and which is capable of obtaining a high-quality image and which is excellent in total performance. In an electrophotographic apparatus provided with a cleaning roller (4), at least a means for rotating a photoconductor (2) after a long period of rest and before an image forming step, and a toner aggregated in the cleaning apparatus (1). The toner is loosened and the toner is selectively adhered to the cleaning roller, and the photosensitive member is polished by a means (5). [Effect] The surface of the cleaning roller is always maintained in a uniform state to prevent abrasion of the surface protective layer of the photoconductor due to agglomerated toner, foreign matter, etc. and damage to the cleaning blade, and the cleaning roller presses the photoconductor appropriately. Are evenly pressure contacted with each other, and a good cleaning effect is achieved by their synergistic effect.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus using an electrostatic transfer process, such as an electrophotographic copying machine and a printer.

[0002]

2. Description of the Related Art In a known image forming apparatus that repeats a step of transferring a transferable toner image formed on a surface of a photoconductor to a transfer material such as paper, after the transfer, residual toner remaining on the surface of the photoconductor is removed by a cleaning unit. There is a need. for that reason,
Conventionally, a cleaning blade made of an elastic material such as rubber has been widely used as this type of cleaning means.

However, this cleaning blade alone is not always effective for removing the adhesion toner, the paper powder, the rosin, the talc, and other deposits adhered and adhered to the surface of the photoreceptor. In order to make up for the drawbacks of such a cleaning blade, a cleaning device has been already used which removes various adhered foreign substances as described above by rubbing a cleaning roller made of an elastic material such as silicone rubber against the surface of the photoconductor under pressure. Proposed. Further, a magnetic cleaning roller composed of a rubbing roller and a magnetic material, a cleaning roller in which a bias is applied to the magnetism opposite to that of the toner, or a cleaning roller in which the cleaning roller itself has a polarity opposite to that of the toner is used. There has already been proposed a cleaning device in which the cleaning roller is rubbed against the surface of the photosensitive member under pressure to remove the various kinds of adhering foreign matter.

Such a cleaning roller is arranged in a cleaning device, and a scraper is arranged in contact with the cleaning roller. Along with the rotation of the cleaning roller, the above-described foreign matter that is slid off from the surface of the photoconductor and the toner collected in the cleaning device for the powder such as toner (hereinafter, collected toner) are collected toner storage parts. In general, a part of the collected toner is coated on the surface of the cleaning roller with a scraper, and the collected toner adhering to the coated surface is rubbed and abraded.

[0005]

However, in the prior art as described above, the recovered toner or the like may be aggregated in the cleaning device, especially in the vicinity of the cleaning roller, after a long rest.

Even after no agglomeration has occurred after a long period of rest, in the electrophotographic apparatus in the image forming process,
In some cases, the temperature near the photoconductor rises and the toner at the contact point between the photoconductor surface and the cleaning roller aggregates when the temperature rises. In particular, amorphous silicon (hereinafter a-Si) having at least amorphous silicon and hydrogen atoms in the photoconductive layer.
In an electrophotographic apparatus using a photoconductor, the temperature of the photoconductor is adjusted, and therefore, when starting after a long rest,
In the image forming step, the surface temperature of the photoconductor rises,
In some cases, the toner at the contact point between the surface of the photoconductor and the cleaning roller aggregates when the temperature rises, causing blocking that damages the cleaning blade.

As described above, if the toner in the vicinity of the cleaning roller is in such a state, it may enter between the scraper and the cleaning roller and damage the edge of the scraper or the cleaning roller. In such a situation, the thickness of the toner coating on the surface of the cleaning roller may locally change, resulting in uneven coating.

Further, the pressure at which the cleaning roller comes into contact with the photosensitive member is locally increased in the longitudinal direction of the roller, and the magnetic material in the toner or the hard particles formed by agglomeration of the toner itself cause the photosensitive member. A part of the surface protective layer may be ground to cause uneven scraping.

As a result, a difference in refraction of incident light with which the photoconductor is irradiated or interference causes a local difference in the effective light amount to the photoconductive layer of the photoconductor, resulting in uneven density of an image, resulting in remarkable image quality. May be deteriorated.

Further, in an electrophotographic apparatus using an a-Si type photoconductor, there is a case where remarkable image blurring, that is, so-called image flow occurs under high humidity.

The present invention solves the above-mentioned problems, suppresses the above-mentioned defects, obtains a stable cleaning action for a long period of time, and obtains a high-quality image. The purpose is to provide a device.

[0012]

In the present invention, attention was paid to the components of the recovered toner coated on the cleaning roller in the sliding rubbing of the cleaning roller as described above.

The collected toner that adheres to the cleaning roller and abrades and abrades the photosensitive member is rubbed, and the collected toner having deteriorated rubbing ability and the uncollected collected toner are mixed.
Their distribution is not always uniform. There is a difference in shape and fluidity between the undeteriorated recovered toner having excellent rubbing ability and the recovered toner used sufficiently. In view of this point, the present invention provides a mechanism for unraveling and controlling the collected toner adhering to the cleaning roller to the cleaning roller in order to equalize not only the coating thickness but also the components. It is designed to be provided.

In order to achieve the above object, in the present invention, in an image forming apparatus such as an electrophotographic apparatus equipped with an elastic cleaning roller and / or a magnetic cleaning roller, at least a toner aggregated in the cleaning apparatus is used. The present invention is characterized in that it has a step of loosening and selectively adhering to the roller to polish the surface of the photoconductor, and a mechanism for rotating the photoconductor after a long rest and before the image forming step.

With this structure, the toner agglomerated by the photoconductor and the toner at a low temperature is selectively diffused, and the surface condition and polishing ability of the cleaning roller are made uniform in the major axis direction. Can be prevented and uneven wear of the surface protective layer of the photoconductor can be prevented.

As a result, a stable cleaning action can always be achieved, and by removing the surface of the photoconductor, corona products can be removed and the image flow can be prevented.

[0017]

Embodiments of the present invention will now be described with reference to the accompanying drawings.

The present invention is by no means limited to the following examples, as long as the effects of the present invention can be obtained.

<Embodiment 1> FIG. 1 is a diagram showing an embodiment of an image forming apparatus according to the present invention. This example was carried out by modifying Canon NP6060.

The cleaning device 1 is disposed in contact with a photoconductor 2 as an image carrier. A cleaning blade 3 and a cleaning roller 4 are arranged in the cleaning device 1. The cleaning roller 4 is preferably made of an elastic material such as silicone rubber or urethane rubber.

The photoconductor 2 is an a-Si type photoconductor and rotates in the direction of arrow A. As is well known, the main charge eliminating light 9, the primary charger 10, and the image signal applying means are provided around the photoconductor 2. 11, a developing device 12, a transfer unit (not shown), a fixing device 13 for fixing the toner image transferred to a transfer material such as paper on the transfer material, and the transfer material is conveyed from the photoconductor 2 to the fixing device 13. The transport system 8 and other image forming members are arranged.

The cleaning roller 4 is in pressure contact with the surface of the photoconductor 2 on the upstream side of the cleaning blade 3 as viewed in the running direction of the photoconductor, and is driven by an appropriate drive source (not shown).
The surface of the photoconductor is rubbed at an appropriate relative speed.

Further, a sub-roller 5 for loosening the cleaning roller so that the cleaning roller 4 is pressed against the cleaning roller 4.
Is provided, the roller 5 rotates so as to have an appropriate relative speed with the cleaning roller 4, and the cleaning roller 4 is moved by changing the pressure for pressing the cleaning roller by a cam linked to the drive source of the cleaning roller 4. Loosen.

A scraper 6 is disposed in contact with the cleaning roller 4, and scrapes off the toner or other foreign matter removed by the cleaning blade 3 or the cleaning roller 4 and drops it into the cleaning device 1 below. Then, it is discharged to the outside by the screw conveyor 7.

In this embodiment, the cleaning roller 4 is made of silicone rubber. Further, the rotation speed of the cleaning roller 4 is 7 times that of the photosensitive member at the contact point with the photosensitive member 2.
It was modified to be 0%.

The sub-roller 5 has a function of loosening the cleaning roller 4 and a function of scraping off the toner.
As shown in FIG. 1, the roller 5 is made of an elastic material such as silicone rubber or urethane rubber, or an elastic material and a magnetic material as described above, or an elastic material like the cleaning roller 4 so as not to damage the cleaning roller 4. A bias having a polarity opposite to that of the toner is applied to the roller, or the roller itself made of an elastic material has a polarity opposite to that of the toner.

In this embodiment, a roller made of silicon rubber was used as the sub roller 5. The toner to be used is an insulating toner having at least a binder resin, and examples of the binder resin include polystyrene and poly-
P-chlorostyrene, homopolymers of styrene such as polyvinyltoluene and its substitution products, styrene-P-chlorostyrene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene copolymers, styrene-acrylic acid esters Copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene Copolymers, styrene copolymers such as styrene-acrylonitrile-indene copolymers, polyvinyl chloride, phenol resins, natural resin modified maleic acid resins, acrylic resins, methacrylic resins,
Polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, polyvinyl butyral, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin and the like can be used.

The toner used in the present invention is formed by mixing the above binder resin with a colorant. As a colorant,
Magnetic powder, pigment, dye, etc. can be used. As the magnetic powder, for example, surface-oxidized or unoxidized iron, nickel,
Metals such as copper, manganese, chromium and rare earths and their alloys, or oxides and ferrites can be used. Carbon black or the like can be used as the pigment.

In addition to these components, a toner formed by adding a lubricant for improving the fluidity of the toner, for example, a material such as SiO ₂ , titanium sanstrontium, cerium oxide or the like is used.

In this embodiment, a means for rotating the photosensitive member is provided before the image forming step after the image forming step has been stopped for a long time,
As shown in FIG. 1, the sub-roller 5 is provided with a mechanism that presses against the cleaning roller 4, and the pressure that presses the roller 4 is changed according to the state of the cleaning roller 4 by an accompanying cam to synchronize with the cleaning roller 4. And rotate at an appropriate relative speed. The roller 5 is pressed against the cleaning roller 4 by a spring when pressed.

Collected toner adheres to the cleaning roller 4, and the photoreceptor 2 is rubbed and polished with SiO ₂ , oxidized / unoxidized iron or the like. This component varies depending on the degree of contribution of the collected toner to the rubbing and polishing. Further, there is a difference in fluidity and shape between the collected toner that has deteriorated due to the sliding friction and the collected toner that has not deteriorated.

By rubbing the sub-roller 5, the collected toner adhering to the cleaning roller 4 is disentangled and the components thereof are dispersed uniformly.

As an extreme example, the NP6060 modified in this embodiment was installed in an environment of a temperature of 30 ° C. and a humidity of 80%, and the current value of the primary charger was adjusted so that an appropriate image could be obtained in a normal state. After that, the power source was turned off and it was left for 24 hours or more.

After that, the power source was turned on, and continuous copy was taken with A3 copy paper using Canon test chart FY9-9058.
058, the same test chart FY9-9060A-01
0 and the same test chart FY9-9073,
From 1 to 10,000 images, the stability in the long axis direction of the photoconductor, the presence or absence of cleaning failure, and the presence or absence of image deletion were evaluated. The results are shown in Table 1.

The judgment method of each evaluation and the meaning of the symbols in the table are shown below.

[Determination of Image Stability in Longitudinal Axis of Photoreceptor] An image is output by a test chart FY9-9058, and a difference in image densities of a portion where the densities of originals are the same from the back of the photoconductor to the front side is visually observed and Macbeth reflection is performed. It judged using the densitometer.

∘: Density difference is less than 0.02, density difference cannot be visually recognized. O ... Density difference is 0.02 or more and less than 0.05, density difference is almost unrecognizable visually. The density difference is 0.05 or more and less than 0.1, and the density difference can be visually recognized. □ ... The density difference is 0.1 or more, and the density difference can be visually recognized. [Judgment of cleaning property] Test chart FY9- 90
73 and the copy paper are shifted so that FY9-9073 is on the front side of the document, and the copy paper is copied at A3. The presence or absence of cleaning failure was evaluated based on the chart of the obtained image and the presence or absence of streaks in the longitudinal direction behind the branch point of the copy sheet, that is, the rotation direction of the photoconductor. If the streaks were visually recognized, it was determined that there was poor cleaning.

∘: No cleaning defect is found ∘: Line in the direction of rotation of the photosensitive member is within 3 mm in width and 2
No more than 1 line: 2 or more lines with a width of 3 mm or less in the rotation direction of the photoconductor 1 or less with 3 mm or more □: One line with a width of 3 mm or less in the rotation direction of the photoconductor 2 or more, 2 or more for 3 mm or more [Presence or absence of image deletion] Whether or not it is possible to distinguish the 8.0 thin line on the same chart by using the test chart FY9-9058 and outputting the image at A3 It was judged by.

The test chart FY9-9060A-
At 010, the lighting voltage for image exposure was made 10 V higher than the lighting voltage at which a proper image was obtained, a copy was made at A3, and the end portions of the characters were visually evaluated.

∘ ... It is possible to determine up to 8.0 and finer lines of 9.0, which are finer than that, without being broken, and FY9-9
060A-010 has no blur at the end of the character ..... It is possible to distinguish the 8.0 thin line without being crushed.
With 9-9060A-010, there is no blur at the end of characters. It is possible to distinguish even fine lines up to 7.0 ...
The thin line of 0 is indistinguishable and FY9-9060A-010
There are some places where the end of characters is blurred. □ ... The thin line of 7.0 cannot be identified, and FY9-906
0A-010 has many blurred character edges [Blade] After continuous copying, observe the side of the cleaner blade that is in contact with the surface of the photoconductor with a microscope to see if there are any burrs. It was judged.

∘: No burr-like part as before continuous copying Δ: Burr-like part is present, but it is minute and does not lead to cleaning failure □ ... Burr-like part is present, and cleaning failure appears in the image

[0042]

[Table 1]

The rotation speed of the cleaning roller 4 is 30 to 99.5% of that of the photosensitive member 2 at the contact point with the photosensitive member 2.
In the range of 100.5 to 200%, favorable results were obtained. More preferably, 50-99.5% or 1
It was in the range of 00.5 to 120%.

By the mechanism of the present invention, the toner or the like that stays in the cleaning device and agglomerates or causes agglomeration during a long period of rest is loosened, especially the toner adhering to the cleaning roller 4 and the above-mentioned foreign substances. Are effectively removed from the cleaning roller 4 to prevent toner blocking.

By diffusing the collected toner by this roller, the collected toner of the same component is uniformly dispersed on the cleaning roller, and not only the coating thickness of the collected toner adhering to the cleaning roller but also the rubbing / polishing force is made uniform. It is possible to prevent uneven interference due to uneven rubbing of the photoconductor.

Further, as an unexpected effect, the image deletion on the trace of the charger disappeared at the time of start-up after a long rest.

This is because the surface of the cleaning roller 4 was kept constant, and at the same time, the rubbing ability for removing foreign matters including corona products on the surface of the photosensitive member was improved, and the foreign matters on the charger were removed. Conceivable.

<Embodiment 2> This embodiment is based on N manufactured by Canon Inc.
It was done by modifying P6060.

FIG. 2 is a diagram showing an embodiment of the electrophotographic apparatus according to the present invention. In this embodiment, as in the first embodiment, a means for rotating the photoconductor is provided before the image forming process after the image forming process is stopped for a long time.

The cleaning device 21 is disposed in contact with the photoconductor 22. A cleaning blade 23 and a cleaning roller 24 are arranged in the cleaning device 21.

The cleaning roller 24 is made of a magnetic material such as a magnet. In this embodiment, the cleaning roller 2
As No. 4, a magnetic cleaning roller made of a rubber magnet was used.

The photoconductor 22 is an a-Si photoconductor and rotates in the direction of the arrow A. As is well known, the main neutralization light 29, the primary charger 30, and the image signal applying means are provided around the photoconductor 22. 31, a developing device 32, a transfer unit (not shown), a fixing device 33 for fixing the toner image transferred to a transfer material such as paper on the transfer material, and the transfer material is conveyed from the photoconductor 22 to the fixing device 33. The transport system 28 and other image forming members are arranged.

The cleaning roller 24 is in pressure contact with the surface of the photoconductor 22 on the upstream side of the cleaning blade 23 as viewed in the running direction of the photoconductor, and is appropriately moved relative to the surface of the photoconductor by an appropriate driving source (not shown). Rubbing at speed.

Further, an ultrasonic vibrator 25 for loosening the toner on the cleaning roller 24 is appropriately arranged so as to come into contact with the cleaning roller 24 so as to come into contact with the cleaning roller 24, and the cleaning roller 24 is driven. Driving the cleaning roller 24 in conjunction with the source,
The cleaning roller 24 is loosened.

A scraper 26 is disposed in contact with the cleaning roller 24, and the cleaning blade 2
3 or the cleaning device 2 by scraping off the toner and other foreign matter removed by the cleaning roller 24.
1 downward, and then the screw conveyor 27
Shall be discharged to the outside.

In this embodiment, a rubber magnet is used for the cleaning roller 24. Further, the rotation speed of the cleaning roller 24 was modified so that it was 70% of that of the photoconductor at the contact point with the photoconductor.

The ultrasonic vibrating element 25 has a function of loosening the cleaning roller 24 and a function of loosening the toner or the like in the cleaning device 21 by vibration. As shown in FIG. The intensity of vibration is adjusted so that the driving of the roller 24 is not hindered and that the cleaning roller 24 and the cleaning blade 23 are not pressed against the photoconductor 22.

In this embodiment, the ultrasonic vibration element 25 is used by being attached to the end of the cleaning roller 24 in the long axis direction.

In this embodiment, the ultrasonic vibration element 25
As shown in FIG. 2, the cleaning roller 24 is arranged in contact with the cleaning roller 24, and the vibration of the cleaning roller 24 is turned on and off according to the driving state of the cleaning roller 24 to loosen the collected toner adhering to the cleaning roller 24.

As an extreme example, the NP6060 modified in this embodiment was installed in an environment of a temperature of 30 ° C. and a humidity of 80%, and the current value of the primary charger was adjusted so that an appropriate image could be obtained in a normal state. After that, the power source was turned off and it was left for 24 hours or more.

After that, the power source was turned on, and continuous copy was taken with a copy sheet of A3 by using the Canon test chart FY9-9058.
058, the same test chart FY9-9060A-01
0 and the same test chart FY9-9073,
From 1 to 10,000 images, the stability in the long axis direction of the photoconductor, the presence or absence of cleaning failure, and the presence or absence of image deletion were evaluated. Table 2 shows the results.

The judgment method of each evaluation and the meaning of the symbols in the table are the same as those in the first embodiment.

[0063]

[Table 2]

The rotation speed of the cleaning roller 24 is 30 to 9 times that of the photosensitive member 22 at the contact point with the photosensitive member 22.
Preferable results were obtained in the range of 9.5% to 100.5 to 200%. More preferably, it was in the range of 50 to 99.5% or 100.5 to 120%.

The mechanism of the present invention loosens the toner or the like that stays in the cleaning device and agglomerates or causes agglomeration during a long period of non-operation, and in particular, recovers the toner adhered to the cleaning roller 24 uniformly. A coating thickness of the collected toner that is dispersed and effectively removes excess collected toner or unnecessary toner and the above-mentioned foreign matter from the cleaning roller 24, and adheres to the surface of the cleaning roller 24.
It also keeps the components constant at all times to prevent homogenization and toner blocking.

Further, as an unexpected effect, the image deletion of the mark of the charger disappeared at the time of start-up after a long period of rest.

It is considered that this is because the surface of the cleaning roller 24 was held constant, and at the same time, the ability to remove foreign matters including corona products on the surface of the photosensitive member was improved, and the foreign matters on the charger were removed. .

<Embodiment 3> In this embodiment, N manufactured by Canon Inc. is used.
It was done by modifying P6060.

FIG. 3 is a diagram showing an embodiment of the electrophotographic apparatus according to the present invention.

The cleaning device 41 is disposed in contact with the photoconductor 42. A cleaning blade 43 and a cleaning roller 44 are arranged in the cleaning device 41.

In this embodiment, as in the first embodiment, a means for rotating the photosensitive member is provided before the image forming step after a long period of rest,
As described above, the cleaning roller may be an elastic roller, an elastic roller to which a bias is applied, a roller itself having a polarity, or the like.

As the cleaning roller 44 used in this embodiment, an elastic roller made of an elastic material and having a polarity opposite to that of the toner is used.

In forming an image, when the cleaning roller is used with plus toner, the cleaning roller is negatively charged, and when silicone rubber is used for the cleaning roller, the inside of the silicone rubber is used. Then, fine silica powder is attached as a reinforcing filler to make it negatively charged.

As known in the art, finely divided silica includes dry silica and wet silica, and commercially available dry silica includes AEROSIL130,200,3 of Nippon Aerosil Co., Ltd.
00, 380, TT600, MOX80, MOX17
0, COK84 CABOT company Cab-O-Sil M5, MS-7,
MS-75, HS-5, EH-5 WACKER-CHEMIE GMBH Company Wacke
r HDK N20, V15, N20E, T30, T4
0 D-C Finesilica Francil, Francol, etc. are available.

As wet silica, Shionogi Pharmaceutical Carplex, Nippon Silica Nipseal, Tokuyama Soda
Tokuseal / Fineseal, Mizusawa Chemical Shilton / Silnex, Kamijima Chemical Star Sil, Ehime Pharmaceutical Himedir, Fuji Devison Chemical Syloid, Shiraishi Engineering Silmos.

The amount of sillin added to the silicone rubber is preferably about 3 to 50 parts by weight per 100 parts by weight of the rubber.

Next, when the cleaning roller is positively charged, the cleaning roller may be positively charged by subjecting the cleaning roller to a silane coupling treatment. RmSiYn (Rm; alkoxyl group or chlorine atom, m is 1 to 3) , Y; an amino group, a vinyl group, a glycidoxy group, a mercapto group, a methacryl group, a ureido group, or a hydrocarbon group containing at least one kind, and n is an integer of 3 to 1).
A silane coupling agent represented by is suitable.

The silica fine powder may be subjected to silane coupling treatment and added to the rubber of the roller material.

As the compound having a vinyl group, H ₂ C = CHSiCl ₃ H ₂ C = CHSi (OC ₂ H ₅ ) ₃ H ₂ C = CHCH ₂ SiCl ₃ H ₂ C = CHCH ₂ Si (CH ₃ ) Cl _{2 H 2 C = CHCH 2 Si (} CH 3) 2 Cl H 2 C = CHCH 2 Si (OC 2 H 5) 3 H 2 C = CHSi (OC 2 H 4 OCH 3) 3 (H 2 C = CHCH 2) 2 SiCl ₂ (H ₂ C = CH) ₂ Si (OC ₂ H ₅ ) ₂ (H ₂ C = CH) ₃ SiOC ₂ H _{5 and the} like are preferable.

As the compound containing a glycidoxy group,

[0081]

Embedded image

As those containing a mercapto group, those containing a HSCH ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ HSCH ₂ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ methacryl group include

[0083]

Embedded image

Examples of compounds containing an ureido group include H ₂ NCONHCH ₂ CH ₂ CH ₂ Si (OC ₂ H ₅ ) ₃ .

A preferred silane coupling agent is a compound containing an amino group and is represented by the following structural formula.

[0086]

Embedded image

[0087]

[Chemical 4]

And the like. Further, the alkoxy group of the above compound may be a chlorine atom. These silane coupling agents may be used alone or in a mixture of two or more.

The cleaning roller having the above structure is used. In this embodiment, the cleaning roller 44 is positively charged.

The photosensitive member 42 is an a-Si photosensitive member which rotates in the direction of the arrow A, and the peripheral portions thereof are, as is well known, the main discharge light 49, the primary charger 50, the image signal applying means. 51, a developing device 52, a transfer unit (not shown), a fixing device 43 for fixing the toner image transferred on a transfer material such as paper to the transfer material, and the transfer material is conveyed from the photoconductor 42 to the fixing device 53. The transport system 48 and other image forming members are arranged.

The cleaning roller 44 is in pressure contact with the surface of the photoconductor 42 on the upstream side of the cleaning blade 43 as viewed in the running direction of the photoconductor, and is appropriately moved relative to the surface of the photoconductor by an appropriate driving source (not shown). Rubbing at speed.

Further, a sub roller 45 for loosening the cleaning roller 44 is appropriately set in the cleaning roller 44 so as to come into pressure contact with the cleaning roller 44, and the cleaning roller 44 is driven in conjunction with the drive source of the cleaning roller 44. The cleaning roller 44 is loosened.

A scraper 46 is disposed in contact with the cleaning roller 44, and the cleaning blade 4
3 or the cleaning device 4 by scraping off the toner and other foreign matter removed by the cleaning roller 44.
1, and then the screw conveyor 47
Shall be discharged to the outside.

In this embodiment, silicon rubber is used for the cleaning roller 44. Also, the cleaning roller 4
The rotation speed of No. 4 was modified to be 70% of that of the photoconductor at the contact point with the photoconductor.

The ultrasonic vibrating element 45 has a function of loosening the cleaning roller 44 and a function of loosening the toner and the like in the cleaning device 41 by vibrating. As shown in FIG. The intensity of vibration is adjusted so as not to hinder the drive of the cleaning roller 44 and to prevent the cleaning roller 44 and the cleaning blade 43 from being pressed against the photosensitive member 42.

In this embodiment, the ultrasonic vibration element 35 is used by being attached to the end portion of the cleaning roller 44 in the long axis direction.

In this embodiment, the element 45 is arranged in contact with the cleaning roller 44 as shown in FIG.
The vibration of the cleaning roller 44 is turned on and off according to the driving state of the cleaning roller 44 to loosen the cleaning roller 44.

As an extreme example, the NP6060 modified in this example was installed in an environment of a temperature of 30 ° C. and a humidity of 80%, and the current value of the temporary charger was adjusted so that an appropriate image could be obtained in a normal state. After that, the power source was turned off and it was left for 24 hours or more.

After that, the power source was turned on, and continuous copying was performed using Canon test chart FY9-9058 on A3 copy paper. On the way, the above chart FY9-9 was used.
058, the same test chart FY9-9060A-01
0 and the same test chart FY9-9073 were used to evaluate the stability in the long axis direction of the photoconductor, the presence or absence of cleaning failure, and the presence or absence of image deletion on images from 1 to 10,000 sheets. The results are shown in Table 3.

Further, the judgment method of each evaluation and the meaning of the symbols in the table are the same as in the first embodiment.

[0101]

[Table 3]

The rotation speed of the cleaning roller 34 is 30 to 9 times that of the photosensitive member 22 at the contact portion with the photosensitive member 32.
Preferable results were obtained in the range of 9.5% to 100.5 to 200%. More preferably, it was in the range of 50 to 99.5% or 100.5 to 120%.

With the mechanism of the present invention, the toner or the like that stays in the cleaning device for a long period of time and is agglomerated or causes the agglomeration is loosened, and particularly the collected toner adhering to the cleaning roller 44 is effective. The toner is effectively dispersed in the cleaning roller 44 to prevent excessive or unnecessary toner and the above-mentioned foreign matter, and toner blocking is prevented.

Further, as an unexpected effect, the image deletion on the trace of the charger disappeared at the time of start-up after long-term rest.

It is considered that this is because the surface of the cleaning roller 44 was kept constant, and at the same time, the ability to remove foreign matters including corona products on the surface of the photosensitive member was improved, and the foreign matters on the charger were removed. .

(Comparative Example 1) FIG. 4 is a diagram showing an example of a comparative example. In this comparative example, as in Example 1, NP6060 manufactured by Canon Inc. was modified and used. The cleaner is provided with a cleaning blade, a cleaning roller and the like as in the cleaner of the embodiment except that there is no roller for loosening the toner adhering to the cleaning roller.

The cleaning device 101 is disposed in contact with the photoconductor 102 as in the first embodiment. A cleaning roller 104 and a cleaning blade 103 are arranged in the cleaning device 101.

The cleaning roller 104 is made of the same material as in the first embodiment.

The photoconductor 102 rotates in the direction of arrow A, and the peripheral portions thereof are, as is well known, the main charge eliminating light 109, the primary charger 110, the image signal giving means 111, and the developing device 11.
3, a transfer unit (not shown), a fixing device 114 for fixing the toner image transferred on a transfer material such as paper to the transfer material, a transfer material transport system 118 and other image forming members are arranged.

The traveling direction of the photoconductor is the same as that of the first embodiment, and the cleaning roller 104 is in pressure contact with the surface of the photoconductor 102 on the upstream side of the cleaning blade 103 as viewed in the direction, and an appropriate not shown is shown. The drive source rubs the surface of the photoconductor at an appropriate relative speed.

A scraper 106 is disposed in contact with the cleaning roller 104, scrapes off the toner and other foreign matters removed by the cleaning blade 103 or the cleaning roller 104, and drops the toner and other foreign substances downward in the cleaning device 101. Then, it is discharged to the outside by the screw conveyor 107.

With the electrophotographic apparatus having such a constitution, continuous copying was carried out in the same manner as in Example 1 without rotating the photosensitive member after long-term rest, and evaluation was carried out. The results are shown in Table 4. Evaluation methods,
The symbols are the same as those shown in Example 1.

[0113]

[Table 4]

(Comparative Example 2) As in Comparative Example 1, Canon NP6060 was modified and used.

Like the cleaner of the embodiment, the cleaner has a mechanism for loosening the toner adhering to the cleaning roller, and is further provided with a cleaning blade, a cleaning roller and the like.

The cleaning device 101 is disposed in contact with the photoconductor 102 as in the first embodiment. A cleaning roller 104 and a cleaning blade 103 are arranged in the cleaning device 101.

The cleaning device 104 is made of the same material as in the first embodiment.

The photoconductor 102 rotates in the direction of arrow A, and the peripheral portions thereof are, as is well known, a main charge eliminating light 109, a primary charger 110, an image signal giving means (not shown), a developing device 113, and a transfer device. Means (not shown) Further, a fixing device 114 for fixing the toner image transferred onto a transfer material such as paper to the transfer material, and other image forming members are arranged.

The cleaning roller 104 is provided on the upstream side of the cleaning blade 103 in the running direction of the photosensitive member.
Is pressed against the surface of the photoconductor 102 and rubbed against the surface of the photoconductor at an appropriate relative speed by an appropriate drive source (not shown).

A scraper 106 is disposed in contact with the cleaning roller 104, scrapes off the toner and other foreign matter removed by the cleaning blade 103 or the cleaning roller 104, and drops the toner and other foreign substances into the cleaning device 101. Then, it is discharged to the outside by the screw conveyor 107.

With the electrophotographic apparatus having such a structure, continuous copying was carried out in the same manner as in Example 1 without rotating the photosensitive member after long-term rest, and evaluation was performed. The results are shown in Table 5. Evaluation methods,
The symbols are the same as those shown in Example 1.

[0122]

[Table 5]

In the above embodiment, as the electrophotographic apparatus,
The copying machine using the a-Si type photoconductor has been described.
The present invention is not limited to the above-described embodiments and can be applied to other electrophotographic apparatuses such as printers, and the photoconductor is not limited to the a-Si based photoconductor, and the OP
It is a material for which a photoconductor such as C, Se, or CdS can be used.

Further, as the means for loosening the toner and the like in the vicinity of the cleaning roller in the cleaning device, the method of pressing the elastic roller and installing the ultrasonic vibration element on the cleaning roller was used, but the brush is installed in the cleaning device. Other methods such as vibrating the cleaning device body are also possible.

[0125]

According to the present invention, as described above, a cleaning device provided with at least a rotation of the photosensitive member before the image forming step, a so-called pre-multi-rotation mechanism, and a mechanism for loosening the cleaning roller, in the cleaning roller, By blocking toner blocking and effectively preventing damage to the photoconductor surface protective layer due to toner blocking, stable images can be obtained not only during normal operation but also after a long rest such as when the power is turned on in the morning. To be

Further, as an unexpected effect, the cleaning roller and the surface of the photosensitive member are rubbed against each other by pre-multi-rotation to effectively remove the corona product adhering to the surface of the photosensitive member near the charger before the image forming process. As a result, it also has the effect of blocking the trace of the charging device after a long rest.

[Brief description of drawings]

FIG. 1 is a diagram of a first embodiment of an electrophotographic apparatus according to the present invention.

FIG. 2 is a diagram of a second embodiment of an electrophotographic apparatus according to the present invention.

FIG. 3 is a diagram of a third embodiment of an electrophotographic apparatus according to the present invention.

FIG. 4 is a diagram showing a comparative example of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cleaning device 2 ... Photosensitive member 3 ... Cleaning blade 4 ... Cleaning roller 5 ... Roller 6 ... Scraper 7 ... Screw conveyor 8 ... Transfer material conveying system 9 ... Main charge eliminating light 10 ... Primary charger 11 ... Image signal applying means 12 ... Developing device 13 ... Fixing device 21 ... Cleaning device 22 ... Photosensitive member 23 ... Cleaning blade 24 ... Cleaning roller 25 ... Ultrasonic vibrating element 26 ... Scraper 27 ... Screw conveyor 28 ... Transfer material conveying system 29 ... Main charge removal light 30 ... Primary charging Device 31 ... Image signal applying means 32 ... Developing device 33 ... Fixing device 41 ... Cleaning device 42 ... Photosensitive member 43 ... Cleaning blade 44 ... Cleaning roller 45 ... Ultrasonic vibration element 46 ... Scraper 47 ... Screw conveyor 48 ... Transfer material conveying system 49 ... Main static elimination light 50 ... Primary charger DESCRIPTION OF SYMBOLS 1 ... Image signal imparting means 50 ... Developing device 53 ... Fixing device 101 ... Cleaning device 102 ... Photosensitive member 103 ... Cleaning blade 104 ... Cleaning roller 106 ... Scraper 107 ... Screw conveyor 108 ... Transfer material conveying system 109 ... Main neutralizing light 110 ... Primary charging device 111 ... Image signal applying means 112 ... Developing device 113 ... Fixing device

Claims (2)

[Claims] 1. An electrophotographic apparatus having a cleaning mechanism, comprising an elastic cleaning roller for cleaning a photosensitive member, wherein a means for rotating the photosensitive member and cleaning are performed at least before the image forming process after a long pause of the image forming process. An electrophotographic apparatus comprising: a unit for loosening collected toner in the apparatus, selectively adhering the collected toner to the cleaning roller, and polishing the photoconductor. 2. An electrophotographic apparatus having a cleaning mechanism, comprising a rubbing member and a magnetic cleaning roller made of a magnetic material such as a magnet, at least in the image forming step after a long rest of the image forming step,
An electrophotographic apparatus comprising: a means for rotating a photosensitive member; and a means for loosening collected toner in a cleaning device, selectively adhering it to the cleaning roller, and polishing the photosensitive member.