JP2002351279A - Cleaning device and image forming device - Google Patents

Abstract

[PROBLEMS] To provide a cleaning device and an image forming apparatus capable of removing foreign substances (toner additive, paper powder, etc.) other than toner attached to an image carrier. SOLUTION: In order to remove a residual toner 22 from a photosensitive drum 1, a fur brush 17 formed of a conductive fiber member is provided, and a collection roller 18 which is conductive and can apply a voltage is provided so as to be in contact with the fur brush. Fur brush 17
Residual toner 2 on photoreceptor drum 1 sent to
2 is first captured by the rotating brush of the fur brush 17,
With the rotation of the fur brush 17, it is guided to the collection roller 18, and the voltage applied to the collection roller 18 causes the collection roller 1 to rotate.
Electrostatic recovery on 8

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus using an electrophotographic system or an electrostatic recording system and a cleaning device therefor.

[0002]

2. Description of the Related Art In recent years,
The image forming apparatus is required to have a high resolution so that a higher precision and higher definition image can be formed. One of means for achieving this is to use a toner having a smaller particle size. Further, conventionally, in order to improve the transfer rate, a toner having an irregular shape and a shape closer to a sphere has been used.
On the other hand, in order to ensure the fluidity of the toner when the particle diameter is reduced, several kinds of additives are generally added to the base particles of the toner.

However, with a conventional cleaning means using only a cleaning blade, it is difficult to clean a spherical small-diameter toner because the toner is easily slipped through, and cleaning failure is likely to occur.

Therefore, as means for replacing the cleaning blade, a fur brush, a collecting roller to which a predetermined bias voltage is applied, and a scraper member thereof are provided.
A so-called bias roller type cleaning device has been generally used. In this scheme,
Good cleaning properties can be obtained for the toner.

However, during use, a toner additive (silica) or paper powder from transfer paper adheres to the image carrier to form a filming layer. The filming layer is formed by rubbing of a brush roll. It cannot be completely removed.
As a result, there is a problem that exposure of the photosensitive member is hindered due to hindrance of cleaning, and as a result, the quality of a recorded image on paper is reduced. Further, when the charging step is performed by the contact charging method, there is a problem that the additive adheres to the contact charging member and inhibits charging.

[0006] In order to remove the filming layer, a cleaning blade is used downstream of the brush cleaning. However, since the toner has good cleaning properties with a brush, the amount of toner that has been input to the blade and also has served as a lubricant decreases, causing problems such as “turning over the blade” and “chipping”. on the other hand,
If the amount of toner input to the blade is increased by intentionally deteriorating the degree of toner removal by the brush, toner and filming can be removed initially, and good cleaning properties can be obtained, but the spherical shape over time Of the toner accumulates between the blade edge and the image carrier, and the toner slips through the blade, causing blade cleaning failure and causing an abnormal image.

[0007] Even when a good cleaning performance is obtained over time by using blade cleaning as a cleaning device when using pulverized toner, silica or paper powder having a smaller particle size than the toner cannot actually be cleaned. May remain on the image carrier. The silica and paper powder that have passed through the cleaning step are adsorbed by the charger itself in the charging step downstream of the photoconductor cleaning. In particular, when a roller is used for the charger, the roller is in contact with or close to the photoconductor,
Adhesion of silica and paper powder appears remarkably.

Further, a voltage is applied to the charging roller, and a discharge occurs between the charging roller and the photosensitive member. For this reason, the silica and paper powder are further attracted to the charging roller by the electrostatic force. As silica and paper powder adhere to the surface of the charging roller, the apparent resistance of the charging roller increases. Then, in order to obtain a predetermined photoconductor charging potential, the bias applied to the charging roller must be higher than usual. In addition, if silica or paper powder adheres to a part, the charging potential cannot be controlled uniformly even if the applied bias is changed,
Charging unevenness having a period of the charging roller occurs, resulting in an abnormal image.

In view of the above-mentioned conventional problems, the present invention provides a cleaning device capable of removing foreign matters (toner additive, paper dust, etc.) other than toner adhered to an image carrier, and an image forming apparatus using the same. The purpose is to provide.

[0010]

According to a first aspect of the present invention, there is provided a cleaning apparatus for an image forming apparatus, comprising: Contacting the filming removing member so as to face the image carrier surface, and applying a voltage to the filming removing member such that a discharge occurs between the filming removing member and the image carrier surface. Features.

According to a second aspect of the present invention, in order to achieve the above object, in the cleaning apparatus of the first aspect, a DC voltage in which an AC voltage is superimposed is applied to the filming removing member.

According to a third aspect of the present invention, in order to achieve the above object, in the cleaning apparatus of the first aspect, the filming removing member is arranged close to the image carrier without being in contact with the image carrier. I do.

According to a fourth aspect of the present invention, in order to achieve the above object, in the cleaning apparatus of the first or second aspect, the filming removing member is a resistor.

According to a fifth aspect of the present invention, in order to achieve the above object, in the cleaning device of the first or third aspect, the filming removing member is an elastic body.

According to a sixth aspect of the present invention, in order to achieve the above object, in the cleaning apparatus of any one of the first to fourth aspects, the filming removing member is a rotating body.

According to a seventh aspect of the present invention, in order to achieve the above object, the cleaning device according to any one of the first to fifth aspects has a cleaning means for removing foreign matter adhered to the surface of the filming removing member. It is characterized by the following.

According to an eighth aspect of the present invention, in order to achieve the above object, in the cleaning apparatus of the sixth or seventh aspect, the cleaning means is a scraper.

According to a ninth aspect of the present invention, in order to achieve the above object, the cleaning device according to the sixth or seventh aspect is characterized in that the cleaning means is a brush having fibers planted therein.

According to a tenth aspect of the present invention, in the image forming apparatus, the means for cleaning the residual toner on the image carrier contacts the residual toner on the image carrier after transferring the image, and rubs the residual toner on the image carrier. A fur brush that scrapes off and contacts a rotating recovery roller while applying a voltage to the fur brush, and electrostatically attracts toner adhering to the fur brush to the recovery roller and adheres to the recovery roller. Cleaning is performed by scraping off the toner with a scraper.

According to an eleventh aspect of the present invention, in order to achieve the above object, in the image forming apparatus of the tenth aspect, the toner used for development is a spherical toner.

[0021]

Embodiments and examples of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view for explaining a main part of an image forming apparatus to which the present invention is applied and an image forming process thereof. Using FIG. 1,
The overall process of the image forming apparatus according to the present invention will be described.

In this apparatus, the photosensitive drum 1 rotates at a speed of, for example, 200 mm / sec in the direction of the arrow in FIG.
The photosensitive drum 1 charged uniformly by the above is exposed to the document image light L via the document reading system and the writing system 3 to form an electrostatic latent image, and the developing device 4 converts the electrostatic latent image to toner. Visualize. Next, the toner image on the photosensitive drum 1 is transferred by the transfer unit 7 onto the transfer paper 6 sent in synchronization with the rotation of the photosensitive drum 1 from the sheet feeding device 5 via the sheet feeding path 5a. . Transfer paper 6 on which the toner image has been transferred
Is separated from the surface of the photoconductor drum 1. At this time, the transfer residual toner slightly remaining on the surface of the photoconductor drum 1 is controlled by the pre-cleaning charger 8 to control the polarity and the charge amount to predetermined states. It is removed by the cleaning device 9. The charge remaining on the photosensitive drum 1 after passing through the cleaning device 9 is removed by a discharge lamp 10. On the other hand, the transfer paper 6 on which the toner image has been transferred
Is guided to the fixing device 12 by the transfer paper transport device 11,
The sheet is discharged to the sheet discharge section 13 in a state where the toner image is fixed by receiving heat and pressure.

Next, the structure and operation of one embodiment of the cleaning device according to the present invention will be described. FIG. 2 is an enlarged cross-sectional view conceptually showing the cleaning device 9 and shows an arrangement state of a filming removing member, a fur brush, and a collection roller. By the above-described image forming process, the pre-cleaning charger 8
The residual toner on the photosensitive drum 1 sent to the cleaning device 9 after passing through the cleaning device 9 reaches the part of the fur brush 17 rotating beyond the entrance seal member 16.

The fur brush 17 is formed of a conductive fiber member, and a collecting roller 18 is provided in contact with the fur brush 17. The collection roller 18 is required to be conductive because a voltage for sucking toner from the fur brush 17 is applied to the collection roller 18. Therefore, the material of the collection roller 18 is, for example, a metal such as stainless steel or a static friction coefficient of the surface. It is preferable to apply or disperse a fluorine-based resin or to perform eutectoid plating with a metal so as to lower the temperature. The fur brush 17 is also in a state where a bias voltage somewhat lower than the bias voltage applied to the collection roller 18 is applied through a contact portion with the collection roller 18.

With the above configuration, the residual toner 22 on the photosensitive drum 1 sent to the part of the fur brush 17
Is first captured by the fur brush 17 by rotating and rubbing of the fur brush 17 (indicated by reference numeral 22a in the figure), and then guided to the collection roller 18 with the rotation of the fur brush 17 and applied to the collection roller 18. It is electrostatically collected on the collection roller 18 by the voltage. The toner collected on the collection roller 18 is sent to the scraper member 19 arranged in contact with the collection roller 18 with the rotation of the collection roller 18 and is scraped off by the rubbing effect between the scraper member 19 and the surface of the collection roller 18 ( It is dropped to the toner discharge coil 20 provided below the collection roller 18 and is appropriately discharged to the outside of the cleaning device 9 by the transport action caused by the rotation of the toner discharge coil 20. . As the blade member of the scraper member 19, for example, a nylon sheet material is used.

The relationship between the tangential velocity vf of the outer diameter position of the fur brush 17 and the tangential velocity vk of the outer diameter position of the collection roller 18 is represented by the ratio of the tangential velocities vf, vk of the outer diameter position to vk ≧ vf.
If conditions are set within a range in which the relationship of × 0.8 is satisfied, desirable recovery efficiency will be obtained. That is, in the cleaning device 9 described above, by setting the conditions in the above range, even if the outer diameter position tangential speed vk or vf is set arbitrarily, the toner collection efficiency from the fur brush 17 to the collection roller 18 can be improved. No significant reduction occurs.

In experiments conducted by the inventors of the present invention, it was observed that a white substance adhered to the surface of the photosensitive drum 1 cleaned by the above-described fur brush cleaning method by use. As a result of IR analysis of the white substance, peaks attributed to silica and paper powder were detected. Therefore, it is considered that this white substance (indicated by reference numeral 22c in the figure) is silica or paper powder.

The photosensitive drum 1 from which the transfer residual toner has been removed by passing through the cleaning portion by the fur brush 17
Reaches a portion facing the filming removing member 14. The filming removing member 14 includes a conductive base 201 connected to a power supply 200 as shown in FIG.
And a resistance layer 202 therearound. Conductive substrate 2
Reference numeral 01 denotes a stainless steel cylinder having a diameter of 8 to 20 mm. The resistance layer 202 is composed of an epichlorohydrin rubber layer and a resin surface layer covering the surface thereof. Alternatively, a thickness of 30 to 700 μm mainly containing a fluororesin such as a tetrafluoroethylene copolymer, a polyvinylidene fluoride, and a tetrafluoroethylene perfluoroalkylvinyl ether copolymer.
m, a resin tube having a surface roughness Rz of about 0.2 to 2 μm may be used. Alternatively, a material capable of performing uniform charging may be used. Since the filming removing member 14 rotates in contact with the photosensitive drum 1, the filming removing member 14 is made of an elastic material in consideration of a reduction in wear of the photosensitive member film over time.

The filming removing member 14 is pressed against the surface of the photosensitive drum 1 at a predetermined pressure (for example, 500 gf) by a pressing means (not shown). Further, in the present embodiment, there is no driving means for the filming removing member 14, and the photosensitive drum 1 is rotated and driven to rotate. The filming removing member 14 has a dimension in the longitudinal direction (axial direction) of the maximum image width A4 (about 30).
0 mm).

The power supply 200 is connected to the filming removing member 14 as described above, and a voltage at which the potential difference between the photosensitive drum 1 and the filming removing member 14 becomes equal to or higher than the discharge starting voltage is applied. In this embodiment, the pre-cleaning charger 8 charges the surface potential of the photosensitive drum 1 before cleaning to, for example, -300V. As a result, discharge occurs near the contact portion between the filming removing member 14 and the photosensitive drum 1, and the charged surface is uniformly charged. With it,
Silica and paper powder are removed by electrostatic force.
Attaches to 4.

Since the filming removing member 14 rotates together with the photosensitive drum 1, the discharge surface moves one after another, and the discharge surface deteriorates as compared with the case where the blade-like filming removing member is used. Can be dispersed over the circumference of the photosensitive drum 1, and the surface deterioration of the photosensitive drum 1 can be reduced.

The voltage applied by the power supply 200 is an AC voltage, for example, a frequency of 1.8 kHz, a peak voltage of 2 kV,
An offset voltage of 300 V is applied. However, when a DC voltage is applied, the amount of generated discharge products is smaller than in the AC voltage superimposed type. Therefore, when it is desired to suppress the generation of ozone and NOx, it is preferable to apply a DC voltage. It should be noted that the adhesion amount of silica and paper powder is larger in the type in which the AC voltage is superimposed. It is considered that this is because the AC superposition type generates a reverse discharge between the filming removing member 14 and the photosensitive drum 1, and the number of discharges is much larger than that of the DC discharge.

Further, the filming removing member 14 is provided with a cleaning member at a location opposite to the location in contact with the photosensitive drum 1 for removing foreign matters such as silica and paper powder attached to the surface. The silica and paper dust are removed from the surface of the film to stabilize the discharge of the filming removing member.

That is, as shown in FIG. 2, the filming removing member 14 is pressed against the scraper 15 so that silica and paper dust can be removed from the filming removing member 14. The material of the scraper 15 is preferably a conductive sponge, a conductive rubber, or a conductive brush. In addition, it is desirable that the scraper 15 be detachable and replaceable so that the scraper 15 can be replaced even if it has deteriorated, so that the effect of removing silica and paper dust is ensured.

In the above-described embodiment, if the static friction coefficient of the surface of the filming removing member 14 is sufficiently small, the photosensitive member 1 may not be rotated together with the photosensitive drum 1. Driving means may be provided. In this case, the filming removing member 14 is driven to rotate in the same direction as the traveling direction of the photosensitive drum 1.

When a non-corotating configuration is adopted, spacers are provided at both ends in the longitudinal direction of the filming removing member 14, and these spacers are brought into contact with the non-image forming areas at both ends of the photosensitive drum 1 so that the photosensitive drum 1 is exposed. A gap is formed between the charged surface on the surface of the drum 1 and the charged surface on the filming removing member 14, so that the surface of the photosensitive drum 1 can be prevented from being worn and deteriorated. In that case, the photosensitive drum 1
The distance at the nearest part of the filming removing member 14 is 5 to
Hold it to be 100 μm. This closest distance is
More preferably, it is good to set to 10-70 micrometers.
Further, in this example, the hardness of the filming removing member 14 may be about 30 to 80 degrees according to JIS-A. However, since it is not necessary to make contact with the photosensitive drum 1, its hardness is 60 to 80 degrees. Alternatively, the hardness may be higher.

Next, an example in which a cleaning means for removing silica and paper dust from the filming removing member 14 is arranged to face the filming removing member will be described. In the following description, an example in which the cleaning unit is brought into contact with the filming removing member 14 will be described. However, when a minute gap can be maintained, the filming removing member 14 and the cleaning unit may be in non-contact. is there.

FIG. 4 is a sectional view showing an example in which the cleaning means is rotatable. The illustrated cleaning means 15a has a roller-like configuration in which a conductive rubber layer 403 is provided on the surface of a stainless steel metal rod 402. The material may be the same as that of the filming removing member 14, and can be rotated similarly to the filming removing member.

Incidentally, it is preferable that the circumferences of the cleaning means 15a and the filming removing member 14 do not become integral multiples. If it is an integral multiple, the same position of the filming removing member 14 and the cleaning unit 15a can keep contacting with each other, so that silica and paper dust are concentrated on a specific surface, and the performance of the cleaning unit 15a becomes uneven. This is because the performance of removing silica and the like is reduced.

A roller-shaped conductive sponge may be used for the cleaning means 15a. This is because the sponge has a porous surface and thus reliably holds silica and paper dust, so that silica and paper dust once adhering to the cleaning means 15a do not adhere to the filming removing member 14.

FIG. 5 is a sectional view showing an example in which the cleaning means has a roller shape made of a conductive brush. The cleaning means 15b in this example is configured by winding a base cloth on which conductive fibers 401 are planted around a surface of a metal rod 402 made of stainless steel. Of course, a brush for charging the brush may be used, but in any case, the filming removing member 1
Rotation is possible in the same manner as 4.

FIG. 6 shows the cleaning means 15 as shown in FIG.
FIG. 6 is a cross-sectional view illustrating an example in which a bias voltage is applied to the power supply b from a power supply 220. As the bias, a voltage more positive than the voltage applied to the filming removing member 14 is preferably applied so that the silica is easily attracted, and a discharge is generated between the two. When a voltage is applied to the cleaning unit 15b as in this example, the discharge between the cleaning unit 15b and the filming removing member 14 can be appropriately controlled, so that silica and paper dust can be reliably removed.

<Experimental Example 1> The present inventors conducted the following experiment in order to confirm the effect of the electrical connection conditions of the cleaning means using this embodiment. A cleaning device equipped with the device according to the first embodiment is installed in the image forming apparatus, and a voltage (frequency: 1.8 kHz, peak voltage: 2 kV) is applied to the filming removing member in synchronization with the rotation of the photosensitive drum. , Offset voltage: 300 V), and continuously output images (5000 copies) using a document chart with an image area ratio of 6%, and silica and paper dust adhere to the filming removing member from the photosensitive drum. It was confirmed. As the cleaning means, a rotatable and brush-shaped roller as in the example shown in FIG. 5 was used. Two types of brushes were prepared: an insulator brush and a medium resistance brush. The cleaning means is rotated in the opposite direction at the same linear velocity at the contact portion with the filming removing member under the condition as shown in FIG. 7 (in the case of a float / potential difference between the filming removing member and the discharge starting voltage. The voltage was applied (when the voltage was applied / when the voltage difference between the filming removal member and the filming removal member was higher than the discharge starting voltage), and continuous copying was performed. Thereafter, the result of taking out the filming removing member and observing the surface under magnification is also shown in FIG. As can be seen from the figure, the cleaning effect is greater when a voltage is applied to the cleaning means such that the potential difference with the filming removing member is equal to or higher than the discharge starting voltage. That is, it can be said that silica and paper dust can be removed from the filming removing means by the discharge of the cleaning means.

When the filming removing member and the cleaning means are not in contact with each other, a spacer member for bringing the filming removing member close to each other can be formed by winding a film around both ends of the filming removing member. The spacer made of such a film material is brought into contact with the filming removing member 14 to generate a desired gap between the filming removing member 14 and the cleaning member. Then, a voltage (DC or A) is applied to the cleaning member.
By applying a C superimposed type voltage) and discharging generated in the gap between the filming removing member 14 and the cleaning member, foreign substances such as silica and paper dust are removed from the filming removing member. When the cleaning member is configured in this manner, silica and paper dust can be removed from the filming removing member 14 by electrostatic force without contact, so that the surface of the filming removing member 14 is prevented from being filled with silica or paper dust. As a result, the discharge of the filming removing member 14 can be stably generated.

FIG. 8 is an enlarged sectional view conceptually showing another embodiment of the cleaning device according to the present invention. The cleaning of the filming removing member 14 in the present embodiment is an example in which the power supply 230 for the filming removing member 14 and the power supply 230 for the cleaning member 15 are shared. In this embodiment, by providing a mode in which a voltage is applied to the filming removing member 14 and a mode in which a voltage is applied to the cleaning member 15, when performing filming removal on the photosensitive drum 1, filming is performed. When a voltage is applied to the removing member 14 and silica and paper dust are removed from the surface of the filming removing member 14, a voltage is applied to the cleaning member 15 and the voltage application destination is switched from the power supply 230 and used. Power supply costs can be reduced. In addition, which of the two is to be applied with a voltage can be determined by arranging a photo sensor opposite to the photoreceptor drum 1 and by the output thereof.

That is, the reflectance of the photosensitive drum 1 when it is new is r0, the reflectance of the drum surface after the rotation time t of the photosensitive drum 1 is rt, and the reflectance r1 when the filming layer is formed is The relationship is r0 <r1, and the reflectance r0 is stored in the reflectance storage means by utilizing the fact that the reflectance returns to r0 when the filming is removed by the filming removing member 15, and the time t, for example, the photosensitive member The reflectance rt of the surface of the photosensitive drum 1 is measured every one rotation time of the drum, and compared with the reflectance r1. If the relationship of rt ≧ r1 is detected, or if n times of continuous detection is performed depending on the detection accuracy, r is determined according to the rotation timing of the photosensitive drum 1.
It is set so that a voltage is applied to the filming removing member 15 until the relation of t <r1 is restored. FIG. 9 shows the relationship between the rotation time of the photosensitive drum 1 and the reflectance of the surface of the photosensitive drum 1 at this time. Then, while the voltage is not applied to the filming removing member 14, the foreign matter is removed from the filming removing member 14 by applying a voltage to the cleaning unit 15.

<Experimental Example 2> The inventors of the present application conducted the following experiment in order to confirm the cleaning effect of the cleaning means on silica and paper powder using the present embodiment. A cleaning device equipped with the device according to the other embodiment described above is installed in an image forming apparatus, and at the start of image formation, no voltage is applied to the cleaning unit, and only the filming removing member is applied with a voltage, and the photosensitive drum is applied. While monitoring the reflectivity of the photo sensor installed opposite to the surface in terms of voltage with an oscilloscope, continuous output of images (5000 copies) using a document chart with an image area ratio of 6%, and filming from the photosensitive drum It was confirmed that silica and paper powder adhered to the removing member. The reflectance at this time was larger than r1.

Next, a voltage was applied to the cleaning means, and no voltage was applied to the filming removing member, so that the image was continuously copied. As the cleaning means, a rotatable brush-shaped roller shown in FIG. 5 was used. Two types of brushes were prepared: an insulator brush and a medium-resistance brush. The voltage was applied under the application conditions shown in Table 2 by rotating the cleaning means in the opposite direction at the same linear velocity at the contact portion with the filming removing member. FIG. 10 shows the result of taking out the filming removing member and observing the surface on an enlarged scale after copying 100 sheets after applying the voltage to the cleaning means.

As shown in the figure, filming removal could not be performed only by rotating and contacting the insulating brush with the filming removing member. Further, filming could not be removed under a voltage application condition in which discharge was not performed even when the medium resistance brush was in contact. However, when a voltage of the discharge starting voltage (about 550 V or more) is applied to the medium resistance brush (No. 3, 4 in FIG. 10), D
Although there was a difference in the removal rate between the C voltage and the AC voltage, silica removal was performed.

Further, a comparative experiment of the remaining toner on the image carrier after forming an image on the image carrier by the same method using the deformed (pulverized) toner and the toner subjected to the sphering process and transferring the image by the transfer unit. Was done. The base material is a polyol resin, the volume average particle size of both toners is 7 μm, and a solid image is formed on a photoreceptor drum under the same image forming conditions (charge, exposure, and development), and then a voltage is applied to the belt transfer unit. To transfer the toner image to the intermediate transfer member. The developing bias was adjusted so that the amount of toner adhered per unit area was the same. The amount of developed toner M1 and the amount of transferred toner M2 transferred to the intermediate transfer member are measured by a suction jig, and the amount of remaining toner M3 is transferred.
And the transfer rate (= M2 / M1 × 100 [%]) are calculated,
FIGS. 11 and 12 are graphs. The horizontal axis is the transfer voltage in both figures. As can be seen from FIG. 11, the transfer residual toner amount remaining on the photosensitive drum was smaller for the spherical toner. Therefore, it can be said that the amount of toner input to the cleaning device is smaller for the spherical toner. In general, the smaller the amount of toner input to the cleaning device, the less the load on the device and the longer the service life. Therefore, the life of the device can be prolonged by using spherical toner.

[0051]

As described above, the cleaning device according to the first aspect of the present invention has an effect that silica and paper dust can be removed from the surface of the image carrier by the discharge of the filming removing member. .

As described above, the cleaning device according to the second aspect has the effect that the discharge is stably generated by superimposing the AC voltage, and the filming can be stably removed. In addition, since the discharge is performed by increasing the peak voltage of the AC voltage without applying a large DC voltage to the positive side, the image carrier is not positively charged, and there is no need for a means for removing OPC other than light. Therefore, there is also an effect that no new cost is generated.

In the cleaning device according to the third aspect, as described above, since the filming removing member does not come into contact with the surface of the image carrier, there is an effect that the deterioration of the surface of the image carrier can be prevented. Further, since the filming removing member can be used even if its hardness is high, there is an effect that the range of material selection is widened.

In the cleaning device according to the fourth aspect, as described above, the discharge between the filming removing member and the image carrier is stabilized by using the filming removing member as a resistor, and the metal is removed. As in the case of using, a discharge having a large energy enough to destroy the filming removing member does not occur, and no charge-up occurs like an insulator, so that the discharge can be stably generated. .

As described above, the cleaning device according to the fifth aspect has the effect of reducing abrasion at the time of contact with the surface of the image carrier by making the filming removing member an elastic body. is there.

In the cleaning device according to the sixth aspect, as described above, when the filming removing member is a rotating body, the discharge surface is not the same surface, and the life can be extended as compared with the shape of a blade or the like. There is an effect that can be.

As described above, the cleaning device according to the seventh aspect removes foreign matter adhering to the surface of the filming removing member, and thus has the effect of preventing reattachment to the surface of the image carrier.

As described above, the cleaning device according to the eighth aspect has an effect that foreign matters can be removed from the filming removing member surface with a simple configuration.

According to the ninth aspect of the present invention, as described above, the foreign matter is removed by rubbing softly with the brush-like cleaning means. There is an effect that foreign matter is not buried and cannot be removed.

According to the tenth aspect of the present invention, as described above, filming of silica and paper powder, which is a problem when using brush cleaning which is advantageous in cleaning spherical toner, is eliminated. There is an effect that can be.

In the image forming apparatus according to the eleventh aspect, as described above, the spherical toner has a higher transfer rate than the irregular toner (crushed toner), so that the amount of toner input to the brush cleaning can be reduced, This has the effect of delaying the deterioration over time and extending the life.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view for explaining a main part of an image forming apparatus to which the present invention is applied and an image forming process thereof.

FIG. 2 is an enlarged sectional view conceptually showing the cleaning device shown in FIG.

FIG. 3 is a cross-sectional view illustrating a configuration example of a filming removing member.

FIG. 4 is a cross-sectional view illustrating an example in which a cleaning unit is rotatable.

FIG. 5 is a cross-sectional view showing an example in which a cleaning unit is formed in a roller shape made of a conductive brush.

6 is a cross-sectional view illustrating an example in which a bias voltage is applied from a power supply to the cleaning unit illustrated in FIG.

FIG. 7 is a diagram showing conditions and results of an experiment performed by the present inventors.

FIG. 8 is an enlarged cross-sectional view conceptually showing another embodiment of the cleaning device according to the present invention.

FIG. 9 is a diagram illustrating a relationship between the rotation time of the photoconductor drum and the reflectance of the photoconductor surface, and a transition of the reflectance when a voltage is applied to the filming removing member.

FIG. 10 is a diagram showing conditions and results of another experiment performed by the present inventors.

FIG. 11 is a diagram illustrating a relationship between a transfer voltage and a transfer residual toner amount of a pulverized toner and a spherical toner.

FIG. 12 is a diagram showing a relationship between a transfer voltage and a transfer rate of a pulverized toner and a spherical toner.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoconductor drum 2 main charger 3 writing means 4 developing device 5 paper feed path 6 transfer paper 7 transfer device 8 pre-cleaning charger 9 cleaning device 10 static elimination lamp 11 transfer paper transport device 12 fixing device 13 paper discharge unit 14 fill Mining removing member 15 Scraper (cleaning member) 15a, 15b Cleaning means 16 Inlet seal member 17 Fur brush 18 Collection roller 19 Scraper member 20 Toner discharge coil 22 Residual toner 22a Toner captured by fur brush 22b Scratched toner 22c Photosensitive White substance adhered to body drum 200 Power supply 201 Conductive substrate 202 Resistive layer 402 Metal rod 403 Conductive rubber layer 220 Power supply 230 Power supply L Exposure

Claims (11)

[Claims] In a cleaning device used in an image forming apparatus, a filming removing member is brought into contact with a surface of the image carrier at a downstream side of a cleaning means for mainly removing toner on the image carrier, and A cleaning device, wherein a voltage that causes a discharge between the filming removing member and the surface of the image carrier is applied to the filming removing member. 2. The cleaning device according to claim 1, wherein
A cleaning device, wherein a DC voltage obtained by superimposing an AC voltage is applied to the filming removing member. 3. The cleaning device according to claim 1, wherein
A cleaning device, wherein the filming removing member is arranged close to the image carrier without contacting the image carrier. 4. The cleaning device according to claim 1, wherein the filming removing member is a resistor. 5. The cleaning device according to claim 1, wherein the filming removing member is an elastic body. 6. The cleaning apparatus according to claim 1, wherein said filming removing member is a rotating body. 7. The cleaning device according to claim 1, further comprising a cleaning unit that removes foreign matter attached to a surface of the filming removing member. 8. The cleaning device according to claim 6, wherein said cleaning means is a scraper. 9. A cleaning device according to claim 6, wherein said cleaning means is in the form of a brush having fibers planted therein. 10. A fur brush, wherein the means for cleaning residual toner on the image carrier is a fur brush which abuts the remaining toner on the image carrier after image transfer, rubs and scrapes the image carrier, The rotating recovery roller is brought into contact with the fur brush while applying a voltage, the toner adhered to the fur brush is electrostatically attracted to the recovery roller, and the toner adhered to the recovery roller is scraped off with a scraper to perform cleaning. An image forming apparatus, comprising: 11. The image forming apparatus according to claim 10, wherein
An image forming apparatus, wherein the toner used for development is a spherical toner.