JP2010164820A - Cleaning device, image carrier unit and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning device including a first cleaning blade and a second cleaning blade and capable of extending the service life of the device, and an image forming apparatus and an image carrier unit including the same. <P>SOLUTION: The belt cleaning device 50 includes, as cleaning blades which come in contact with a transfer belt 20 as a surface moving body to be cleaned, to remove deposits on a surface of the transfer belt 20, a first blade 56 which is a first cleaning blade disposed on an upstream side in the surface moving direction of the transfer belt 20, and a second blade 59 which is a second cleaning blade disposed on a downstream side in the surface moving direction, wherein the first blade 56 is kept in contact with the surface of the transfer belt 20 from the beginning of use of the device, and the second blade 59 is kept away from the surface of the transfer belt 20 at the beginning of use of the device and brought into contact with the surface of the transfer belt 20 after the passage of a predetermined period of time from the beginning of use. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cleaning device used in an image forming apparatus such as a copying machine, a facsimile machine, a printer, and the like, and an image forming apparatus and an image carrier unit having the same.

Conventionally, as a cleaning device for removing toner remaining on an image bearing member such as a photosensitive member or an intermediate transfer belt after transferring a toner image as a member to be cleaned, a cleaning blade made of an elastic material such as rubber is brought into contact with the image. A blade cleaning system for removing toner on a carrier is known.
In such a blade cleaning system, when one cleaning blade is in contact with the image carrier, if the contact portion of the cleaning blade with the image carrier is worn, the cleaning performance is deteriorated and the life of the cleaning device is increased. .
Patent Documents 1 and 2 propose a cleaning device in which two cleaning blades are arranged in the direction of surface movement of an image carrier as a configuration capable of extending the life of a blade cleaning type cleaning device. With such a cleaning device, even if the toner passes through the contact position between the first cleaning blade disposed on the upstream side of the image carrier in the surface movement direction and the image carrier, the surface movement direction of the image carrier Cleaning is performed by a second cleaning blade disposed on the upstream side.

However, in the configuration of the cleaning device described in Patent Document 1 or Patent Document 2, there is a problem that the second cleaning blade disposed on the downstream side in the surface movement direction of the image carrier is unnecessarily worn.
Hereinafter, this defect will be described.
At the beginning of the use of a new cleaning device, the contact portion of the first cleaning blade arranged on the upstream side of the surface movement direction of the image carrier is not worn and the cleaning performance is high, so the toner on the image carrier Almost all of this is removed by the first cleaning blade. As a result, almost no toner is input to the contact position between the second cleaning blade and the image carrier, and therefore the second cleaning blade hardly contributes to toner cleaning. However, since the second cleaning blade is also in contact with the image carrier, wear of the contact portion of the second cleaning blade with respect to the image carrier proceeds. As described above, although the second cleaning blade hardly contributes to the cleaning of the toner, the progress of wear of the contact portion causes a problem that the second cleaning blade is unnecessarily worn.

As described above, if the second cleaning blade is worn unnecessarily, the second cleaning blade is quickly worn, and the second cleaning blade is cleaned with respect to the toner that has passed through the contact position between the first cleaning blade and the image carrier. The deterioration of the property is accelerated, and the life of the cleaning device is reduced.
Such a problem is not limited to the case where the object to be cleaned by the cleaning device is an image carrier, but may be a surface moving body to which an adherent such as toner adheres, such as a recording medium conveying member that conveys a recording medium. It is a problem that can occur.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a cleaning device that includes a first cleaning blade and a second cleaning blade, and which can extend the life of the device, and the same. An image forming apparatus and an image carrier unit are provided.

In order to achieve the above object, the invention according to claim 1 is directed to a surface moving direction of the object to be cleaned as a cleaning blade that comes into contact with the object to be cleaned and removes deposits on the surface of the object to be cleaned. In the cleaning device having a first cleaning blade disposed on the upstream side and a second cleaning blade disposed on the downstream side in the surface movement direction, the first cleaning blade is disposed on the object to be cleaned from the start of use of the cleaning device. The second cleaning blade is separated from the surface of the object to be cleaned at the start of use of the cleaning device, and is brought into contact with the surface of the object to be cleaned after a predetermined period from the start of use. To do.
According to a second aspect of the present invention, in the cleaning device of the first aspect, the first cleaning blade and the second cleaning blade are made of a conductive material, and a first power source for applying a voltage to the first cleaning blade is provided. The first power supply has a second power supply that applies a voltage having a polarity opposite to that of the voltage applied to the first cleaning blade to the second cleaning blade.
According to a third aspect of the present invention, in the cleaning device according to the first or second aspect, the predetermined period is a predetermined time during which the surface movement time of the object to be cleaned from the start of use of the cleaning device is predetermined. It is a period until it reaches.
According to a fourth aspect of the present invention, in the cleaning device according to the first, second, or third aspect, the object to be cleaned is a surface moving body that is disposed in the image forming apparatus and to which toner can adhere. This is a period from the start until the number of images formed by the image forming apparatus reaches a predetermined number.
According to a fifth aspect of the present invention, there is provided a latent image carrier, a charging unit for charging the latent image carrier, a latent image forming unit for forming an electrostatic latent image on the latent image carrier, and the latent image. Developing means for developing the electrostatic latent image on the carrier with toner to form a toner image, transfer means for transferring the toner image on the latent image carrier to a transfer body or a recording medium, and carrying the latent image after transfer 5. An image forming apparatus comprising: a latent image carrier cleaning unit that removes transfer residual toner adhering to a surface of a body to be cleaned; and the latent image carrier cleaning unit as the latent image carrier cleaning unit. It is characterized by using an apparatus.
According to a sixth aspect of the present invention, in the image forming apparatus according to the fifth aspect of the present invention, the developing unit includes a plurality of developing devices each containing toner of different colors, and the plurality of developing devices are provided for one latent image carrier. The developing devices are opposed to each other.
According to a seventh aspect of the present invention, in the image forming apparatus according to the fifth aspect, the developing unit includes a plurality of developing devices containing toners of different colors, and the same number of latent image carriers as the plurality of developing devices. And one of the plurality of developing devices is opposed to one latent image carrier.
According to the present invention, the image carrier, the toner image forming means for forming a toner image on the image carrier, and the toner image formed on the image carrier are primarily transferred to the intermediate transfer member. Primary transfer means, secondary transfer means for transferring the toner image on the intermediate transfer body to a transfer body or a recording medium, and transfer residual toner adhered to the surface using the intermediate transfer body after secondary transfer as a cleaning target In the image forming apparatus having the intermediate transfer member cleaning means to be removed, the cleaning device according to claim 1, 2, 3 or 4 is used as the intermediate transfer member cleaning means.
According to a ninth aspect of the present invention, an image carrier, a toner image forming unit for forming a toner image on the image carrier, and a toner image formed on the image carrier are transferred to a recording medium at a transfer position. Transfer means for fixing, a fixing means for fixing the toner image on the recording medium onto which the toner image has been transferred at a fixing position, a recording medium conveying member for carrying and conveying the recording medium from the transfer position toward the fixing position, An image forming apparatus having a recording medium conveying member cleaning means for removing unnecessary toner adhering to the surface using the recording medium conveying member as a member to be cleaned, as the recording medium conveying member cleaning means. The cleaning device is used.
According to a tenth aspect of the present invention, in the image forming apparatus according to the fifth, sixth, or seventh aspect, the latent image carrier is a photosensitive layer made of amorphous silicon.
According to an eleventh aspect of the present invention, in the image forming apparatus according to the fifth, sixth or seventh aspect, the latent image carrier is made of a material in which a filler is dispersed.
The invention according to claim 12 is the image forming apparatus according to claim 5, 6 or 7, wherein the latent image carrier is a photoconductor using a cross-linked charge transport material, or a surface layer reinforced with a filler. An organic photoconductor having at least one of the constitutions of photoconductors having the above is used.
According to a thirteenth aspect of the present invention, in the image forming apparatus according to any of the fifth to twelfth aspects, a toner having a shape factor SF-1 in the range of 100 to 150 is used as the toner for forming the toner image. It is characterized by.
According to a fourteenth aspect of the present invention, there is provided an image carrier unit that integrally supports an image carrier that is a member to be cleaned and a cleaning unit that cleans at least the surface of the image carrier, and is detachable from the main body of the image forming apparatus. The cleaning device of claim 1, 2, 3 or 4 is used as the cleaning means.

  In the present invention, the second cleaning blade is separated from the surface of the object to be cleaned until the predetermined period elapses from the start of use of the cleaning device. The contact between the second cleaning blade and the object to be cleaned can be suppressed in a state where almost no toner is input to the position. Accordingly, it is possible to suppress the wear of the contact portion from progressing in a state where the second cleaning blade hardly contributes to the toner cleaning, and it is possible to suppress unnecessary wear of the second cleaning blade.

  According to the present invention, unnecessary wear of the second cleaning blade can be suppressed, so that the wear of the second cleaning blade can be prevented from being accelerated and the cleaning performance can be maintained. There is an excellent effect that can be achieved.

1 is a schematic configuration diagram of a belt cleaning device of Example 1 according to the present embodiment. 1 is a schematic configuration diagram illustrating a printer according to an embodiment. 6 is a graph comparing the amount of toner passing through the contact position of the polarity control blade when a voltage is applied to the polarity control blade and when no voltage is applied when a high toner adhesion amount is input after the number of prints of 200 [kp]. 6 is a graph showing a relationship between an ID value and a toner adhesion amount. 3 is a graph showing a charge potential distribution after secondary transfer of toner carried on a transfer belt and a charge potential distribution of residual toner after passing through a contact position of a polarity control blade. The graph which shows the change of the charge potential distribution of the transfer residual toner when the voltage applied to a polarity control blade is changed. Explanatory drawing of the abrasion by use of a contact point where a polarity control blade contacts a transfer belt. Explanatory drawing of the layer structure of an amorphous silicon photoconductor. The figure which represented the shape of the toner typically in order to demonstrate shape factor SF-1. FIG. 5 is a schematic configuration diagram of a belt cleaning device according to a second embodiment. FIG. 6 is a schematic configuration diagram of a belt cleaning device according to a third embodiment. FIG. 6 is a schematic configuration diagram of a belt cleaning device according to a fourth embodiment. FIG. 10 is a schematic configuration diagram of a belt cleaning device according to a fifth embodiment. FIG. 10 is a schematic configuration diagram of a photoconductor cleaning device of Example 6. FIG. 9 is an explanatory diagram of a main part of a printer according to a first modification. FIG. 10 is an explanatory diagram of a main part of a printer according to a second modification. Explanatory drawing of the image formation unit of the modification 2. FIG.

Hereinafter, an embodiment in which the present invention is applied to a full-color printer (hereinafter referred to as a printer 100) which is an image forming apparatus will be described.
FIG. 2 is a configuration diagram illustrating a schematic configuration of the printer 100.
As shown in FIG. 2, the printer 100 includes an apparatus main body 1 that is fixed in position for storing each component as an image forming unit, and a drawable paper feed cassette 2 for storing transfer paper P. An image forming unit 3Y, 3C, 3M, 3K for forming toner images of each color of yellow (Y), cyan (C), magenta (M), and black (K) is provided at the center of the apparatus main body 1. ing. Hereinafter, the subscripts Y, C, M, and K of the respective symbols indicate members for yellow, cyan, magenta, and black, respectively.

  As shown in FIG. 2, the image forming units 3Y, 3C, 3M, and 3K have drum-shaped photoconductors 10Y, 10C, 10M, and 10K that are rotated in the direction of the arrow in FIG. It has. The photoreceptor 10 is composed of an aluminum cylindrical base and an OPC (organic photo semiconductor) photosensitive layer that covers the surface of the photoreceptor. Each image forming unit 3 is developed around the photosensitive member 10 using a charging device 11Y, 11C, 11M, or 11K for charging the photosensitive member 10, and a toner for storing a latent image formed on the photosensitive member 10. 12Y, 12C, 12M, 12K. Further, photoconductor cleaning devices 13Y, 13C, 13M, and 13K for cleaning residual toner on the photoconductor 10 are provided. Below each image forming unit 3, an optical unit 4 is provided as an exposure unit capable of irradiating the photoreceptors 10Y, 10C, 10M, and 10K with the laser light L. Further, above each image forming unit 3, an intermediate transfer unit 5 including a transfer belt 20 to which a toner image formed by each image forming unit 3 is transferred is provided.

Note that a series of image forming processes of image formation of the printer 100 is performed here with N / P (negative positive: toner adheres to a place where the potential is low).
Further, a fixing device 6 for fixing the toner image transferred to the transfer belt 20 to the transfer paper P is provided. In addition, toner bottles 7Y, 7C, 7M, and 7K that store toner of each color of yellow (Y), cyan (C), magenta (M), and black (K) are loaded on the upper portion of the apparatus main body 1. . The toner bottles 7 </ b> Y, 7 </ b> C, 7 </ b> M, and 7 </ b> K are configured to be detachable from the apparatus main body 1 by opening a paper discharge tray 8 formed on the upper part of the apparatus main body 1.
The printer 100 also includes a control unit (not shown) that controls each unit of the printer 100 such as each image forming unit 3, the intermediate transfer unit 5, the optical unit 4, and the fixing device 6.

  The optical unit 4 reflects laser light L emitted from a laser diode as a light source by a polygon mirror or the like, and sequentially scans the photosensitive members 10Y, 10C, 10M, and 10K while irradiating them. The transfer belt 20 of the intermediate transfer unit 5 is wound around a drive roller 21, a tension roller 22, and a driven roller 23, and is driven to rotate counterclockwise in the drawing at a predetermined timing. The intermediate transfer unit 5 includes primary transfer rollers 24Y, 24C, 24M, and 24K that transfer the toner images formed on the photoreceptors 10Y, 10C, 10M, and 10K to the transfer belt 20. The intermediate transfer unit 5 includes a secondary transfer roller 25 that transfers the toner image transferred onto the transfer belt 20 onto the transfer paper P, and a belt that cleans residual toner on the transfer belt 20 that has not been transferred onto the transfer paper P. A cleaning device 50 is provided. A transfer belt 20 is formed on the transfer belt 20 for toner density control at a position facing the transfer belt 20 on the downstream side in the surface movement direction of the transfer belt 20 with respect to a position facing the secondary transfer roller 25. A P sensor pattern detector 85 for detecting the density of the pattern image to be processed is arranged.

Next, the process of obtaining a color image in the printer 100 will be described.
When a print button of an operation unit (not shown) is pressed or an image formation signal is received from an external device (not shown), the control unit starts a predetermined operation of each unit necessary for image formation and outputs a predetermined voltage. Alternatively, the image forming operation is started by controlling the current to be applied. When the image forming operation is started, driving from a driving source (not shown) is transmitted to the driving roller 21 and the photosensitive members 10Y, 10C, 10M, and 10K, and the transfer belt 20 moves in the counterclockwise direction in FIG. The photosensitive members 10Y, 10C, 10M, and 10K start to rotate in the clockwise direction in FIG.
In the image forming units 3Y, 3C, 3M, and 3K, the surfaces of the photoconductors 10Y, 10C, 10M, and 10K that are rotationally driven by a drive source (not shown) are all covered by a charging roller included in the charging devices 11Y, 11C, 11M, and 11K. It is charged like this. Thereafter, the optical unit 4 scans and exposes the laser light L based on image information corresponding to each color, and forms latent images on the surfaces of the photoreceptors 10Y, 10C, 10M, and 10K. The latent images on the photoconductors 10Y, 10C, 10M, and 10K are developed with the toners of the respective colors carried on the developing rollers of the developing devices 12Y, 12C, 12M, and 12K, and are visualized as toner images. The toner images on the photoreceptors 10Y, 10C, 10M, and 10K are sequentially superimposed and transferred onto the transfer belt 20 that is rotated counterclockwise by the action of the primary transfer rollers 24Y, 24C, 24M, and 24K. The image forming operation for each color at this time is executed while shifting the timing from the upstream side toward the downstream side in the moving direction of the transfer belt 20 so that the toner image is transferred to the same position on the transfer belt 20. The The surfaces of the photoreceptors 10Y, 10C, 10M, and 10K after the completion of the primary transfer are cleaned by the cleaning blades of the photoreceptor cleaning devices 13Y, 13C, 13M, and 13K, and are prepared for the next image formation. The toner filled in the toner bottles 7Y, 7C, 7M, and 7K is placed in the developing devices 12Y, 12C, 12M, and 12K of the image forming units 3Y, 3C, 3M, and 3K by a conveyance path (not shown) as necessary. A fixed amount is supplied.

On the other hand, the transfer paper P in the paper feed cassette 2 is conveyed into the apparatus main body 1 by a paper feed roller 27 disposed in the vicinity of the paper feed cassette 2 and is transferred at a predetermined timing by a pair of registration rollers 28. 20 and the secondary transfer roller 25 are conveyed to the opposing secondary transfer portion. Then, the toner image formed on the transfer belt 20 is transferred to the transfer paper P in the secondary transfer portion. The transfer paper P onto which the toner image has been transferred passes through the fixing device 6 to be fixed, and is discharged to the paper discharge tray 8 by the discharge roller 29. Similar to the photoconductor 10, the untransferred toner remaining on the transfer belt 20 is transferred to the position of the driven roller 23 by the surface movement of the transfer belt 20, and is positioned at a position facing the driven roller 23 with the transfer belt 20 interposed therebetween. Cleaning is performed by the arranged belt cleaning device 50. Thereby, the surface of the transfer belt 20 is prepared for the next image formation.
The order of arrangement of the four image forming units 3Y, 3C, 3M, and 3K and the toner bottles 7Y, 7C, 7M, and 7K is not limited to the example illustrated in FIG.

The photoreceptor cleaning device 13Y includes a collected toner transport device that transports the collected toner collected from the surface of the photoreceptor 10Y by the cleaning member. Further, a lubricant application device that applies a lubricant to the surface of the photoconductor 10Y may be disposed on the downstream side in the rotation direction of the photoconductor 10Y with respect to the position where the cleaning member contacts the photoconductor 10Y. The lubricant application device consists of a solid lubricant and a brush roller. The brush roller that contacts the photoconductor 10Y and the solid lubricant while rotating scrapes off the solid lubricant and applies the shaved lubricant to the photoconductor 10Y. It is the structure to do.
The image forming unit 3Y integrally supports the photosensitive member 10Y, the charging device 11Y, the developing device 12Y, the photosensitive member cleaning device 13Y, and the like, and constitutes a process cartridge that is detachable from the printer 100 main body. The other three image forming units 3C, 3M, and 3K have the same configuration, and are detachable from the main body of the printer 100 as process cartridges.

[Example 1]
FIG. 1 is an enlarged explanatory view of a first example (hereinafter referred to as Example 1) of a belt cleaning device 50 provided in the printer 100 of the present embodiment.
Arranged in the casing 51 of the belt cleaning device 50 so as to come into contact with the surface of the transfer belt 20 in the order of the inlet seal 53, the first blade 56, and the second blade 59 from the upstream side of the surface movement direction of the transfer belt 20. Has been.
The first blade holder 58 that supports the first blade 56 is rotatable about the first blade shaft 54, and the first blade holder 58 is positioned at the opposite end of the first blade 56 across the first blade shaft 54. A pressure spring 57 is fixed. The contraction force of the first blade pressing spring 57 acts on the first blade holder 58, so that the first blade 56 comes into pressure contact with the transfer belt 20.
Further, the second blade holder 61 that supports the second blade 59 is rotatable about the second blade shaft 64, and the second blade holder 61 has a second blade shaft 64 sandwiched between the second blade 59 and the second blade 59 on the opposite end of the second blade 59. A two-blade pressure spring 66 is fixed. The contraction force of the second blade pressing spring 66 acts on the second blade holder 61, so that the second blade 59 presses against the transfer belt 20. Further, the belt cleaning device 50 presses a portion of the second blade holder 61 between the second blade shaft 64 and the second blade pressure spring 66 to contact the second blade 59 away from the transfer belt 20. A separation cam 65 is provided. In the state shown in FIG. 1, the pressing of the second blade holder 61 by the contact / separation cam 65 is released, and the second blade 59 is in contact with the transfer belt 20. From this state, when the contact / separation cam 65 is rotated 180 [°] in the direction of arrow A, the contact / separation cam 65 presses the second blade holder 61, so that the second blade holder 61 moves the second blade shaft 64. It rotates in the counterclockwise direction in the figure, and the second blade 59 is separated from the transfer belt 20 as indicated by an arrow B in FIG.

  The inlet seal 53 is a sheet member made of polyurethane rubber having a thickness of 0.2 [mm] so as not to scrape off the transfer residual toner on the transfer belt 20, and has an abutting angle of 11 [°] with respect to the transfer belt 20. The transfer belt 20 is in contact with the surface movement direction so as to be in the trailing direction so that the amount of biting into the driven roller 23 that is a roller is 1 [mm]. The entrance seal 53 prevents the toner scraped off from the transfer belt 20 by the first blade 56 from being scattered outside the belt cleaning device 50.

As shown in FIG. 1, a conductive material to which a negative polarity voltage is applied from the first blade power supply 55 is located at a position facing the surface of the transfer belt 20 on the downstream side in the surface movement direction of the transfer belt 20 with respect to the inlet seal 53. A first blade 56 made of an elastic blade is arranged. The first blade 56 is disposed so as to be in the counter direction with respect to the surface movement direction of the transfer belt 20.
In the first embodiment, the first blade power supply 55 applies a constant voltage of −2 [kV] to the first blade 56, but the first blade power supply 55 is −80 [μA] to the first blade 56. A constant current of about −100 [μA] may be applied.
The belt cleaning device 50 is provided below the first blade 56 with a toner discharge coil 62 that conveys the transfer residual toner removed by the belt cleaning device 50 to a waste toner bottle (not shown) disposed outside the belt cleaning device 50.

At a position facing the surface of the transfer belt 20 on the downstream side of the surface movement direction of the transfer belt 20 with respect to the first blade 56, a first elastic blade made of a conductive elastic blade to which a negative polarity voltage is applied from the second blade power source 67 is provided. Two blades 59 are arranged.
In the first embodiment, the second blade power supply 67 applies a constant voltage of −3 [kV] to the second blade 59. However, the second blade power supply 67 applies −120 [μA] to the second blade 59. A constant current of about −150 [μA] may be applied.
The second blade 59 is arranged so as to be in a counter direction with respect to the surface movement direction of the transfer belt 20. As will be described in detail later, the control unit 200 controls the second blade contact / separation mechanism 65 a of the second blade 59. By doing so, the transfer belt 20 can be contacted and separated. Further, a toner discharge guide 63 for guiding the transfer residual toner removed by the second blade 59 to the toner discharge coil 62 is disposed between the second blade 59 and the toner discharge coil 62.

The polarity of the voltage applied to the first blade 56 and the second blade 59 may be opposite to that of the first embodiment.
In the first embodiment, a voltage having the same polarity is applied to the first blade 56 and the second blade 59, but a voltage having a different polarity is applied to the first blade 56 and the second blade 59. Also good. Furthermore, when different voltages are applied to the first blade 56 and the second blade 59, the polarity of the voltage applied to the first blade 56 can be either positive or negative.

In addition, the q / d distribution (charge amount distribution) shown below is measured by an E-spurt analyzer manufactured by Hosokawa Micron, and the vertical axis indicates the ratio to the collected number, and the horizontal axis indicates the charge amount of one toner.
Since the printer 100 according to the present embodiment has a small amount of toner remaining after transfer, the number of toners collected this time is 500.
In the graph in which the vertical axis shown in FIG. 3 indicates the residual cleaning ID, the toner on the transfer belt 20 after passing through the position where the first blade 56 abuts is tape-transferred with a scotch tape, and is affixed onto paper, and is spectroscopically measured. Measured with a colorimeter (X-light manufactured by Amtech), measured with a spectrocolorimeter on the other hand with only the scotch tape attached to the paper, and only the scotch tape from the reflection density of the tape transferred onto the transfer belt 20 The value obtained by subtracting the reflection density.
Further, there is a correlation between the ID and the number of toners (toner adhesion amount) as shown in FIG. 4, and the ID value increases as the number of toners increases. Therefore, the cleaning property can be determined by measuring the ID.

Next, cleaning of transfer residual toner by the belt cleaning device 50 will be described.
The toner remaining on the transfer belt 20 that is not transferred to the transfer paper P in the secondary transfer portion moves to a position where the driven roller 23 and the belt cleaning device 50 face each other with the transfer belt 20 sandwiched by the surface movement of the transfer belt 20. Then, it passes through a position where the entrance seal 53 contacts the transfer belt 20.
The polarity distribution of the charge of the transfer residual toner on the transfer belt 20 before passing through the position where the first blade 56 abuts is affected by the electric field at the secondary transfer portion, and the graph shown in FIG. Thus, the q / d distribution is a state in which + and -polarity are mixed.
The untransferred toner on the transfer belt 20 is scraped off from the transfer belt 20 by the first blade 56 when passing through a position where the first blade 56 contacts, and most of the toner is removed. The transfer residual toner scraped off by the first blade 56 falls to the lower left side in FIG. 1 as it is and is discharged out of the unit of the belt cleaning device 50 by the toner discharge coil 62.

Normal transfer residual toner (attachment amount: about 0.05 [mg / cm ² ]) is almost completely removed by the first blade 56 to which a voltage is applied. Although details will be described later, even after a high toner adhesion amount after jamming (adhesion amount: about 0.6 [mg / cm ² ]), from the start of use of the belt cleaning device 50 to a certain number (200 [kp]). Is almost completely removed. However, after printing a certain number of prints, the untransferred toner begins to slip through the contact position between the transfer belt 20 and the first blade 56. As described above, when the transfer residual toner passes through the contact position of the first blade 56, the first blade 56 to which a negative polarity voltage is applied causes the negative polarity as shown in the graph of FIG. 5B. The charging polarity can be aligned.

The transfer toner that has passed the position where the first blade 56 contacts the transfer belt 20 is transferred to the position where the second blade 59 contacts the transfer belt 20 due to the surface movement of the transfer belt 20, and the second blade 59 causes the transfer belt 20 to move. It is removed from the surface.
In the present embodiment, the unit of the number of prints is 1000 prints [kp], which is the length of the transfer paper is A4 landscape (length in the paper traveling direction: 210 [mm], perpendicular to the paper traveling direction). : 297 [mm]). Further, in this embodiment, when there is no description about the toner adhesion amount, the toner adhesion amount of normal transfer residual toner (0.05 [mg / cm ² ]).

Next, the transfer residual toner on the transfer belt 20 passing through the contact position between the first blade 56 and the transfer belt 20 to which a voltage having the same polarity as the toner (constant voltage control at −80 [kV]) is applied. Details when the charging polarities are aligned will be described.
The electrical resistance of the first blade 56 is 10 ⁶ to 10 ⁸ [Ω · cm], the contact pressure of the first blade 56 against the transfer belt 20 is 20 [g / cm], and the first blade 56 is It is configured so as to come into counter contact with the surface movement direction.

6 shows the q / d distribution (“transfer residual toner” in FIG. 6) of the toner before the transfer residual toner on the transfer belt 20 passes through the contact portion with the first blade 56, and the first blade 56. Showing the q / d distribution of the toner when the intensity of the voltage applied to the toner is changed (three steps of -2 [kV], -3 [kV], and -4 [kV] in constant voltage control). It is.
The amount of charge of the residual toner that passes through the contact position of the first blade 56 is “friction charging”, “charge injection”, “discharge”, and the like by the transfer belt 20 and the first blade 56 as shown in FIG. As described above, the toner is shifted to the normal charging polarity (negative polarity in the first embodiment) as the applied voltage (or current) increases.

When the toner is sandwiched between the first blade 56 and the transfer belt 20, a part of the current flows into the transfer residual toner by the voltage (or current) applied to the first blade 56, and the transfer residual toner is applied. It is charged with the polarity on the voltage side and passes through the contact position of the first blade 56.
It is considered that the change in the charging polarity of the transfer residual toner in this state is mainly due to the discharge between the first blade 56 and the transfer belt 20.
Although the surface potential of the transfer belt 20 after passing through the secondary transfer portion varies depending on the transfer conditions, it has been confirmed that the potential varies within a range of −100 [V] to +100 [V].
Therefore, when the applied voltage to the first blade 56 shown in FIG. 6 is “−2 [kV]”, the potential difference is 2100 [V] (−100 [V]) when the surface potential of the transfer belt 20 is +100 [V]. 1900 [V]), and a sufficient potential difference is generated, so that the discharge starts. As a result, the q / d distribution of the untransferred toner after passing through the contact position of the first blade 56 is shifted to the negative polarity side.

Further, at the contact position of the first blade 56, the transfer residual toner is applied to the applied voltage by the discharge of the minute gap portion of the wedge formed by the transfer belt 20 and the first blade 56 on the entrance side and the exit side of the contact position. The amount of charge shifts to the same polarity side.
At the abutting position of the first blade 56, the transfer residual toner transferred by the surface movement of the transfer belt 20 is mechanically scraped off. Is dirty with toner. For this reason, the discharge of the minute gap portion at the contact position of the first blade 56 is mainly performed at the wedge portion on the outlet side.

Next, details of the cleaning performance of the first blade 56 will be described.
The first blade 56 has substantially the same contact condition as the insulating cleaning blade used in the conventional cleaning device, and blocks (scratches off) the transfer residual toner in addition to the function of aligning the polarity of the transfer residual toner to one side. There is a function.

Further, as described above, the contact condition of the first blade 56 to the transfer belt 20 is substantially the same as the contact condition of the insulating cleaning blade provided in the conventional cleaning device to the object to be cleaned. In addition to the function of aligning the toner, there is a function of blocking (scraping off) transfer residual toner.
Toner removal with a conventional insulating cleaning blade is considered that the toner blocked at the contact position forms a weir on the wedge formed by the object to be cleaned and the cleaning blade, thereby blocking the subsequent toner. It has been.
On the other hand, the first blade 56 of the belt cleaning device 50 according to the first exemplary embodiment has almost the same linear pressure as the insulating cleaning blade, and the first blade 56 includes a part of the toner polarity (+, − of the transfer residual toner). Since a voltage (or current) having a polarity (-polarity) opposite to that of the transfer residual toner on the positive polarity side) is applied, a toner weir is positively formed in the wedge portion.

That is, the toner charged to a polarity opposite to the voltage (or current) applied to the first blade 56 is held by the first blade 56 with an electrically strong force, and the toner weir formed on the wedge portion collapses. It becomes a difficult and strong weir and can block the subsequent transfer residual toner.
Therefore, not only the transfer residual toner at the time of normal image formation but also the transfer residual toner almost completely up to a certain number (200 [kp]) even when a high toner adhesion amount toner is input after jamming or the like. And is hardly slipped through the contact position of the first blade 56.
In addition, although the charging polarity of the input toner is negative at the contact position of the second blade 59, a negative polarity voltage having a larger absolute value than the voltage applied to the first blade 56 is applied. Even with the negative polarity toner that has passed through the first blade 56, an electric field that attracts the toner to the second blade 59 is formed, and a toner weir is formed.

FIG. 3 is a graph comparing the cleaning performance when a negative polarity voltage is applied to the first blade 56 and when it is not applied. Specifically, a high toner adhesion amount (adhesion amount: 0.6 [0.6] is applied to the first blade 56 when the voltage of −2 [kV] constant voltage control is applied and when no voltage is applied. mg / cm ² ]) is a graph showing the remaining cleaning ID of the surface of the transfer belt 20 that has passed the contact position of the first blade 56 after 200 kp use.
As is apparent from FIG. 3, it can be understood that the cleaning performance is greatly improved when a voltage is applied to the cleaning blade (the first blade 56 of Example 1).
However, as with the conventional insulating cleaning blade, the ridgeline that is in contact with the transfer belt 20 also wears gradually with the first blade 56 to which voltage is applied.

FIGS. 7A and 7B are explanatory diagrams of wear due to the aging of the contact point 56t where the first blade 56 contacts the transfer belt 20, FIG. 7A shows the start of use, and FIG. 7B shows the state after 200 [kp]. FIG. 7C is an explanatory diagram after 400 [kp]. The first blade 56 gradually wears over time as shown in FIGS. 7B and 7C, and the amount of toner that passes through the contact position of the first blade 56 gradually increases. .
FIGS. 7B and 7C are diagrams showing the wear width of the ridge line by enlarging the ridge line in contact with the transfer belt 20 shown in FIG. .
It is known that the wear on the edge of the cleaning blade (first blade 56 in Example 1) increases in proportion to the travel distance of the transfer belt 20, and in this experiment, it is also proportional to the travel distance of the transfer belt 20. It was confirmed that the wear width increased.

When wear of the first blade 56 has progressed, voltage (or current) is applied to the untransferred toner up to the wear amount (400 [kp]) shown in FIG. It was confirmed that the first blade 56 can be removed almost completely.
However, after 200 [kp] and at a high toner adhesion amount (0.6 [mg / cm ² ]) such as after jamming, as shown in the graph of “−2 [kV] applied” in FIG. The toner slips through.
Here, in the graph of “-2 [kV] applied” in FIG. 3, the amount of toner passing through the contact position of the first blade 56 is about “0.005” in ID, and the ID shown in FIG. According to the graph showing the relationship with the toner adhesion amount, it is about 0.03 [mg / cm ² ]. This toner adhesion amount can be almost completely removed by the second blade 59 disposed on the downstream side of the first blade 56.

Although details will be described later, in the belt cleaning device 50, the second blade 59 is brought into contact with the transfer belt 20 after 200 [kp].
After the second blade 59 is brought into contact with the transfer belt 20, wear begins in the same manner as the first blade 56. Then, 200 [kp] after the second blade 59 is brought into contact with the transfer belt 20, that is, 400 [kp] after the start of use of the belt cleaning device 50, the use of the belt cleaning device 50 is started. It wears to the same extent as the amount of wear after 200 [kp] (the state shown in FIG. 7B).
On the other hand, the first blade 56 has a wear amount after 400 [kp] as shown in FIG. At this time, the normal amount of toner remaining after transfer can be cleaned almost completely by the first blade 56. However, when the amount of toner adhesion is high, such as when a jam occurs, the toner cannot be completely cleaned and the toner slips through a little.
At this time, the amount of toner passing through the contact position of the first blade 56 is approximately double that in the case of ID of 200 [kp], and converted to the adhesion amount, 0.07 [mg / cm from the graph of FIG. ² ], and the second blade 59 disposed on the downstream side can be almost completely cleaned.

  After that, when the first blade 56 and the second blade 59 are brought into contact with each other and are worn together, the toner will slip through the contact position of the second blade 59, resulting in poor cleaning and the life of the belt cleaning device 50. Experimentally, when a high toner adhesion amount is inputted at about 500 [kp], the toner slips from the contact position of the second blade 59.

  Even after 200 [kp], when a high adhesion amount of toner is input, it is almost after the jam. Therefore, if the transfer belt 20 is rotated two or three times, only the first blade 56 is substantially complete. However, the next image formation is delayed by the time required to make two or three rounds. On the other hand, if the second blade 59 is provided on the downstream side of the first blade 56 as in the belt cleaning device 50 of the first embodiment, even when a high toner adhesion amount of toner is input, The surface of the transfer belt 20 can be almost completely cleaned only once by passing the portion facing the belt cleaning device 50, and the next image formation can be performed in a short time.

Next, the operation of the first blade 56 and the second blade 59 of the belt cleaning device 50 will be described.
The first blade 56 is always in pressure contact with the transfer belt 20 by the pressure of the first blade pressure spring 57.
The second blade 59 is also configured to be pressed against the transfer belt 20 by the pressure of the second blade pressing spring 66. However, when the new belt cleaning device 50 starts to be used, the contact / separation cam 65 is stopped by rotating 180 [deg.] Counterclockwise from the state shown in FIG. It is in a state separated from 20. Until the transfer belt 20 reaches a predetermined travel distance from the start of use of the belt cleaning device 50 or until the predetermined number of prints reaches a predetermined number (200 [kp]), the second blade 59 is It is in a state of being separated from the transfer belt 20.
When a detection unit (not shown) detects that a predetermined period has elapsed since the start of use of the belt cleaning device 50, the control unit 200 controls the second blade contact / separation mechanism 65a based on the detection result of the detection unit. Then, the contact / separation cam 65 is rotated 180 ° in the counterclockwise direction and stopped. As a result, the contact / separation cam 65 is in the state shown in FIG. 1, and the second blade 59 contacts the transfer belt 20.

  As described above, the belt cleaning device 50 according to the first embodiment separates the second blade 59 from the surface of the transfer belt 20 until the predetermined period has elapsed from the start of use. The contact between the second blade 59 and the transfer belt 20 in a state where almost no toner is input to the contact position with the toner 20 can be suppressed. Thereby, it is possible to suppress the wear of the contact portion from progressing in a state where the second blade 59 hardly contributes to the cleaning of the toner, and it is possible to suppress unnecessary wear of the second blade 59.

Hereinafter, specific configurations such as characteristic values and contact conditions of each component of the belt cleaning device 50 according to the first embodiment will be described.
First, specific configuration conditions of the transfer belt 20 are shown below.
・ Linear speed of transfer belt: 138 [mm / s]
As a material of the transfer belt 20, a synthetic resin such as polyimide, polycarbonate, polyester, or polypropylene, or various rubbers containing an appropriate amount of a conductive agent such as carbon black is used, and its volume resistivity is 10 ⁶ to 10 ⁶ . What is 10 ¹⁴ [Ω · cm] is used.
Further, an elastic belt having elasticity can be used as the transfer belt 20, and in this case, silicon rubber, NBR, H-NBR, CR, EPDM, urethane rubber or the like is used as the main base material of the conductive elastic layer. The material of the conductive protective layer is not particularly limited as long as it can achieve the objectives of reducing frictional resistance, stability of electrical characteristics to the environment, and improving residual toner cleaning performance by reducing surface roughness. Fluororesin polymers such as tetrafluoroethylene (PTFE), a copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether (PFA), PVdF, and the like are used in alcohol-soluble nylon, silicon resin, silane coupler, and urethane resin emulsions. A paint dissolved and dispersed in an organic solvent can be used.
The above-mentioned conductive protective layer can be provided by applying the above-mentioned paint by dip coating, spray coating, electrostatic coating, roll coating or the like. Furthermore, by subjecting the protective layer to surface treatment or polishing, it is possible to improve mold release properties, conductivity, wear resistance, surface cleaning properties, and the like.

Specific configuration conditions of the first blade 56 are shown below.
-Electrical resistance of blade: 10 ⁶ to 10 ⁸ [Ω · cm]
Contact direction: Contact with the counter with respect to the surface movement direction of the transfer belt 20 Contact angle: 20 [°] with respect to the transfer belt 20
Contact pressure: 20 [g / cm] linear pressure
-Applied voltage: -2 [kV] for constant voltage control (or -80 [μA] for constant current control)
The first blade 56 is constituted by a plate-like member bonded on a first blade holder 58 made of sheet metal, and has a thickness of 2 [mm], a free length of 7 [mm], and a JIS-A hardness meter of 60 to 60 mm. 80, the rebound resilience of 30 [%] was used, but other values can be used.
In addition, an acrylic coat layer (about 5 [μm]) is provided on at least the surface of the first blade 56 that contacts the transfer belt 20. This coat layer is for reducing wear of the first blade 56.

Next, specific configuration conditions of the second blade 59 are shown below.
-Electrical resistance of blade: 10 ⁶ to 10 ⁸ [Ω · cm]
Contact direction: Contact with the counter with respect to the surface movement direction of the transfer belt 20 Contact angle: 20 [°] with respect to the transfer belt 20
Contact pressure: 20 [g / cm] linear pressure
Applied voltage: -3 [kV] with constant voltage control (or -120 [μA] with constant current control)
The second blade 59 is composed of a plate-like member bonded on a second blade holder 61 made of sheet metal, and has a thickness of 2 [mm], a free length of 7 [mm], and a JIS-A hardness meter of 60 to 60 mm. 80, the rebound resilience of 30 [%] was used, but other values can be used.
In addition, an acrylic coat layer (about 5 [μm]) is provided on at least the surface of the second blade 59 that contacts the transfer belt 20. This coat layer is for reducing wear of the second blade 59.

Specific configuration conditions of the inlet seal 53 are shown below.
・ Material: Polyurethane rubber ・ Thickness: 0.2 [mm]
・ Free length: 7 [mm]
Contact angle with the transfer belt 20: 11 [°]
The amount of biting into the transfer belt 20: 1 [mm]

Next, the photoreceptors 10Y, 10M, 10C, and 10K used in the printer 100 of the present embodiment will be described in detail.
As the photoreceptor 10 used in the present embodiment, a conductive support is heated to 50 [° C.] to 400 [° C.], and a vacuum deposition method, a sputtering method, an ion plating method, a thermal CVD method, Using an amorphous silicon photoconductor (hereinafter referred to as “a-Si photoconductor”) having a photoconductive layer made of amorphous silicon (a-Si) by a film forming method such as a photo CVD method or a plasma CVD method. Can do. Among them, a plasma CVD method, that is, a method in which a source gas is decomposed by direct current, high frequency or microwave glow discharge to form an a-Si deposited film on a support is preferably used.

The layer structure of the a-Si photoconductor described above is, for example, as follows.
FIG. 8 is a schematic configuration diagram for explaining a layer configuration. In the a-Si-based photoconductor 500 shown in FIG. 8A, a photoconductive layer 502 made of a-Si: H, X and having photoconductivity is provided on a support 501. An a-Si photoconductor 500 shown in FIG. 8B has a photoconductive layer 502 made of a-Si: H, X and having photoconductivity on a support 501, an amorphous silicon surface layer 503, and the like. It is composed of An a-Si photoconductor 500 shown in FIG. 8C has a photoconductive layer 502 made of a-Si: H, X and having photoconductivity on a support 501, an amorphous silicon surface layer 503, and the like. And an amorphous silicon-based charge injection blocking layer 504. In the a-Si type photoreceptor 500 shown in FIG. 8D, a photoconductive layer 502 is provided on a support 501. The photoconductive layer 502 includes a charge generation layer 505 made of a-Si: H, X and a charge transport layer 506, and an amorphous silicon-based surface layer 503 is provided thereon.

The support 501 of the a-Si photoconductor 500 described above may be conductive or electrically insulating. Examples of the conductive support include metals such as Al, Cr, Mo, Au, In, Nb, Te, V, Ti, Pt, Pd, and Fe, and alloys thereof such as stainless steel. Also, a surface of the side on which at least the photosensitive layer is formed of an electrically insulating support such as polyester, polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polystyrene, polyamide, or a synthetic resin film or sheet, glass, ceramic, etc. It is also possible to use a support obtained by conducting a conductive treatment.
The shape of the support 501 can be a smooth surface, a cylindrical or plate-like surface having an uneven surface, or an endless belt, and the thickness thereof is appropriately determined so that a desired photoreceptor for an image forming apparatus can be formed. However, when flexibility as a photoreceptor for an image forming apparatus is required, it can be made as thin as possible within a range where the function as the support 501 can be sufficiently exhibited. However, the support 501 is usually set to 10 [μm] or more from the viewpoints of manufacturing and handling, mechanical strength, and the like.

The a-Si-based photoconductor 500 that can be used in this embodiment functions to prevent the injection of charges from the conductive support side between the conductive support 501 and the photoconductive layer 502 as necessary. It is more effective to provide an amorphous silicon-based charge injection blocking layer 504 (FIG. 8C). In other words, the amorphous silicon-based charge injection blocking layer 504 has a function of blocking charge injection from the support 501 side to the photoconductive layer 502 side when the photosensitive layer is subjected to a charging process with a certain polarity on its free surface. It has a so-called polarity dependency that does not exhibit such a function when it is subjected to a charging process with the opposite polarity. In order to provide such a function, the amorphous silicon type charge injection blocking layer 504 contains a relatively large amount of atoms for controlling conductivity as compared with the photoconductive layer 502.
The thickness of the amorphous silicon based charge injection blocking layer 504 is preferably 0.1 to 5 [μm], more preferably 0.3 to 4 in view of obtaining desired electrophotographic characteristics and economic effects. [Μm], optimally 0.5 to 3 [μm] is desirable.

  The photoconductive layer 502 is formed on the undercoat layer as necessary, and the layer thickness of the photoconductive layer 502 is appropriately determined as desired from the viewpoints of obtaining desired electrophotographic characteristics and economic effects. Is preferably 1 to 100 [μm], more preferably 20 to 50 [μm], and most preferably 23 to 45 [μm].

The charge transport layer 506 is a layer mainly having a function of transporting charges when the photoconductive layer 502 is functionally separated. The charge transport layer 506 includes at least silicon atoms, carbon atoms, and fluorine atoms as constituent elements, and is formed of a-SiC (H, F, O) including hydrogen atoms and oxygen atoms as required. It has photoconductive properties, particularly charge retention properties, charge generation properties, and charge transport properties. In the present invention, it is particularly preferable to contain an oxygen atom.
The layer thickness of the charge transport layer 506 is appropriately determined as desired from the viewpoint of obtaining desired electrophotographic characteristics and economic effects. The charge transport layer 506 is preferably 5 to 50 [μm], more preferably Is preferably 10 to 40 [μm], and most preferably 20 to 30 [μm].

The charge generation layer 505 is a layer mainly having a function of generating charges when the photoconductive layer 502 is functionally separated. This charge generation layer 505 is composed of a-Si: H containing at least silicon atoms as components and substantially not containing carbon atoms, and if necessary containing hydrogen atoms, and has desired photoconductive properties, particularly charge generation. Characteristics and charge transport characteristics.
The layer thickness of the charge generation layer 505 is appropriately determined as desired from the viewpoints of obtaining desired electrophotographic characteristics and economic effects, and preferably 0.5 to 15 [μm], more preferably 1 to 10. [Μm], optimally 1 to 5 [μm].

If necessary, the a-Si-based photoreceptor 500 that can be used for the photoreceptor 10 of the present embodiment is further provided with a surface layer on the photoconductive layer 502 formed on the support 501 as described above. The amorphous silicon surface layer 503 is preferably formed. The amorphous silicon-based surface layer 503 has a free surface and is provided to achieve the object of the present invention mainly in moisture resistance, continuous repeated use characteristics, electrical pressure resistance, use environment characteristics, and durability.
The thickness of the amorphous silicon-based surface layer 503 is usually 0.01 to 3 [μm], preferably 0.05 to 2 [μm], and most preferably 0.1 to 1 [μm]. Is desirable. If the layer thickness is less than 0.01 [μm], the amorphous silicon surface layer 503 is lost due to wear or the like during use of the photosensitive member, and if it exceeds 3 [μm], electrons such as an increase in residual potential are generated. Deterioration of photographic characteristics is observed.

  The a-Si photosensitive member 500 has a high surface hardness, shows high sensitivity to long wavelength light such as a semiconductor laser (770 to 800 [nm]), and hardly deteriorates due to repeated use. Therefore, it is an electrophotographic photoreceptor suitable for use in a high-speed copying machine, a laser beam printer (LBP), or the like.

  Alternatively, an organic photoreceptor in which a photosensitive layer is provided on a conductive support, a filler is contained in the surface layer coated on the photosensitive layer, and the charge transport material is a cross-linked charge transport material may be used. Abrasion resistance can be improved by incorporating a particulate material in the surface layer of the organic photoreceptor and using a cross-linked charge transport material as the charge transport material.

  Examples of the surface layer of the photoreceptor include a polymer or copolymer of a compound selected from vinyl fluoride, vinylidene fluoride, chlorotrifluoroethylene, tetrafluoroethylene, hexafluoropropylene, and perfluoroalkyl vinyl ether. Moreover, as a filler contained in a surface layer, although an organic filler and an inorganic filler may be used, an inorganic filler is used especially preferable. Examples of the organic filler material include fluororesin powder such as polytetrafluoroethylene, silicon resin powder, and a-carbon powder. Examples of the inorganic filler material include silica, tin oxide, zinc oxide, titanium oxide, alumina, and oxide. Metal oxides such as zirconium, indium oxide, antimony oxide, bismuth oxide, calcium oxide, tin oxide doped with antimony, tin-doped indium oxide, metal fluorides such as tin fluoride, calcium fluoride, aluminum fluoride, Examples thereof include potassium titanate and boron nitride. These fillers may be used alone or in combination of two or more. In order to improve dispersibility, these fillers may be surface treated with a surface treatment agent.

  As the conductive support, a metal such as aluminum or stainless steel, a cylindrical cylinder such as paper or plastic, or a film is used. An undercoat layer (adhesive layer) having a barrier function and an undercoat function can be provided on these supports. The undercoat layer is used to improve the adhesion of the photosensitive layer, improve coating properties, protect the support, cover defects on the support, improve charge injection from the support, and protect the electrical coating of the photosensitive layer. It is formed. Known materials for the undercoat layer include polyvinyl alcohol, poly-N-vinylimidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, ethylene-acrylic acid copolymer, casein, polyamide, copolymer nylon, glue, gelatin, and the like. These are dissolved in a solvent suitable for each and coated on a support. The film thickness is about 0.2 to 2 [μm].

  Specific examples of the photosensitive layer include those having a laminated structure of a charge generation layer containing a charge generation material and a charge transport layer containing a charge transport material, and a single layer containing a charge generation material and a charge transport material. There are things that consist of.

  Examples of charge generation materials include pyrylium, thiopyrylium dyes, phthalocyanine pigments, anthanthrone pigments, dibenzpyrenequinone pigments, pyranthrone pigments, trisazo pigments, disazo pigments, azo pigments, indigo pigments, quinacridone pigments, asymmetric quinocyanine, quinocyanine, etc. Can be used.

  Examples of charge transport materials include pyrene, N-ethylcarbazole, N-isopropylcarbazole, N-methyl-N-phenylhydrazino-3-methylidene-9-ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-9 -Ethylcarbazole, N, N-diphenylhydrazino-3-methylidene-10-ethylphenothiazine, N, N-diphenylhydrazino-3-methylidene-10-ethylphenoxazine, p-diethylaminobenzaldehyde-N, N-diphenylhydrazone , Triarylmethane compounds such as p-diethylaminobenzaldehyde-2-methylphenyl-phenylmethane, 1,1-bis (4-N, N-diethylamino-2-methylphenyl) heptane, 1,1,2, 2-tetrakis (4-N, N-dimethyl) Polyaryl alkanes such as amino-2-methylphenyl) ethane, and triaryl amines, or the like can be used.

  Further, a photosensitive layer may be provided in which a protective layer is provided on the outermost surface and a filler is added for the purpose of improving the wear resistance of the protective layer. Examples of organic fillers include fluorine resin powders such as polytetrafluoroethylene, silicon resin powders, and a-carbon powders. Examples of inorganic fillers include metal powders such as copper, tin, aluminum, and indium, tin oxide, and oxidation. Examples thereof include zinc, titanium oxide, indium oxide, antimony oxide, bismuth oxide, tin oxide doped with antimony, metal oxides such as tin-doped indium oxide, and inorganic materials such as potassium titanate. These fillers may be used alone or in combination of two or more. These fillers can be dispersed by using a suitable disperser in the protective layer coating solution. The average particle size of the filler is preferably 0.5 [μm] or less, and preferably 0.2 [μm] or less from the viewpoint of the transmittance of the protective layer. Moreover, you may add a plasticizer and a leveling agent in a protective layer in embodiment.

Next, the toner suitably used for the printer 100 of the present embodiment will be described.
In recent years, an image forming apparatus is required to have a high resolution so that a high-precision and high-definition image can be formed. One means for achieving this is to use a toner having a smaller particle size. Further, in order to improve the transfer rate, a toner having an infinite shape and a shape closer to a sphere has been used.
However, in a blade cleaning method in which an insulating cleaning blade used in a conventional cleaning device is in contact with an image carrier, cleaning a small particle size toner or a spherical toner has a small particle size or a shape. Due to the spherical shape, the toner is likely to slip through the contact position of the blade, resulting in poor cleaning and difficult cleaning. However, since the image quality is improved when a small particle size toner or a spherical toner is used, it is desirable to use a small particle size spherical toner.
In the belt cleaning apparatus 50 according to the first exemplary embodiment, the first blade 56 to which a voltage is applied is brought into contact with the transfer belt 20 to electrostatically form a toner weir at the contact position. Even when spherical toner is used, it is possible to perform better cleaning as compared with a configuration using a conventional insulating cleaning blade. Further, by providing a second blade 59 to which a voltage is applied on the downstream side in the surface movement direction of the transfer belt 20 with respect to the contact position of the first blade 56 with the transfer belt 20, the contact position of the first blade 56 The toner that has passed through can be more reliably removed. The printer 100 can achieve high image quality by using spherical toner having a small particle diameter.

In the printer 100 of this embodiment, so-called spherical toner having a high roundness with a shape factor SF-1 of 100 to 150 is used as the toner. When spherical toner is used, toner removal from the transfer belt 20 by the cleaning blade is less than when pulverized toner is used. However, in this embodiment, since the transfer residual toner is removed from the transfer belt 20 by the first blade 56 and the second blade 59 to which a voltage is applied, the cleaning performance can be maintained even when spherical toner is used. .
When the shape of the toner is close to a sphere, the contact state between the toner and the toner or the toner and the toner image carrier becomes a point contact, so that the adsorbing force between the toners is weakened and the fluidity is increased. The attracting force with the toner image carrier is also weakened, and the transfer rate is increased. When the shape factor SF-1 exceeds 150, the transfer rate decreases, which is not preferable.
FIG. 9 is a diagram schematically showing the shape of the toner in order to explain the shape factor SF-1. The shape factor SF-1 indicates the ratio of the roundness of the toner shape and is represented by the following formula (1). A value obtained by dividing the square of the maximum length MXLNG of a shape formed by projecting a spherical substance (toner in the present embodiment) onto a two-dimensional plane by the figure area AREA and multiplying by 100π / 4.
In other words,
SF-1 = {(MXLNG) ² / AREA} × (100π / 4) (1)
Is defined by

[Example 2]
Next, a second embodiment (hereinafter referred to as a second embodiment) of the belt cleaning device 50 will be described.
FIG. 10 is an enlarged explanatory diagram of the belt cleaning device 50 according to the second embodiment.
The belt cleaning device 50 according to the second embodiment is different from the belt cleaning device 50 according to the first embodiment in that a lubricant supply device 70 is provided on the downstream side in the surface movement direction of the transfer belt 20 with respect to the second blade 59. The point is common. Therefore, only differences from the first embodiment will be described here.
As illustrated in FIG. 10, the lubricant supply device 70 included in the belt cleaning device 50 according to the second embodiment includes a brush roller that contacts the transfer belt 20 on the downstream side in the surface movement direction of the transfer belt 20 with respect to the second blade 59. An applicator brush 69 is provided. The lubricant supply device 70 further includes a solid lubricant 71 made of zinc stearate and a lubricant pressure spring 72 as a biasing member that biases the solid lubricant 71 against the application brush 69.

Specific configuration conditions of the application brush 69 are shown below.
・ Brush material: Conductive polyester ・ Brush hair length: 4 [mm]
The amount of biting into the transfer belt 20: 1 [mm]
-Linear speed of application brush: 138 [mm / s] (same linear speed as transfer belt 20)
・ Applied voltage to the rotating shaft of the application brush: Earth ・ Original resistance of brush fiber: 10 ⁷ [Ω · cm]
・ Brush flocking density: 10 [10,000 / inch ² ]
・ Brush form: Inclined to the downstream side of the brush rotation direction ・ Brush roller diameter: Φ14 [mm]
・ Rotation direction: counterclockwise in FIG.

Since the belt cleaning device 50 according to the second embodiment separates the second blade 59 from the surface of the transfer belt 20 from the start of use until the predetermined period elapses as in the first embodiment, unnecessary wear of the second blade 59 is caused. Can be suppressed, and the life of the apparatus can be extended.
In general, it is known that when a lubricant is applied to the surface of a toner object to be cleaned such as the transfer belt 20, toner removal by the cleaning blade is improved and wear of the cleaning blade is reduced. For this reason, the lifetime of the cleaning device can be further extended by adopting a configuration including the lubricant supply device as in the second embodiment.

Example 3
Next, a third example (hereinafter referred to as Example 3) of the belt cleaning device 50 will be described.
FIG. 11 is an enlarged explanatory view of the belt cleaning device 50 according to the third embodiment.
In the belt cleaning device 50 according to the third embodiment, the first blade power supply 55 applies a positive polarity voltage to the first blade 56 made of a conductive material, and an insulating blade member is used as the second blade 59. The second blade 59 is different from the second embodiment in that no voltage is applied.
By changing the second blade 59 on the downstream side in the surface movement direction of the transfer belt 20 from a conductive blade to which a voltage is applied to an insulating blade, toner removal by the second blade 59 is achieved as compared with the configuration of the second embodiment. Sex declines. However, the belt cleaning device 50 according to the third embodiment separates the second blade 59 from the surface of the transfer belt 20 until the predetermined period elapses from the start of use as in the second embodiment. Wear can be suppressed. Therefore, the lifetime of the apparatus can be extended as compared with a conventional cleaning apparatus having two cleaning blades.
In the third embodiment, a positive polarity voltage is applied to the first blade 56, but a reverse polarity (negative polarity) voltage may be applied.

Example 4
Next, a fourth embodiment (hereinafter referred to as a fourth embodiment) of the belt cleaning device 50 will be described.
FIG. 12 is an enlarged explanatory diagram of the belt cleaning device 50 according to the fourth embodiment.
In the belt cleaning device 50 of the fourth embodiment, the second blade power supply 67 applies a positive polarity voltage to the second blade 59 made of a conductive material, and an insulating blade member is used as the first blade 56. The first blade 56 is different from the second embodiment in that no voltage is applied.
By changing the first blade 56 on the upstream side of the transfer belt 20 in the surface movement direction from a conductive blade to which a voltage is applied to an insulating blade, the toner removal performance as a cleaning device can be improved as compared with the configuration of the second embodiment. descend. However, the belt cleaning device 50 according to the fourth embodiment separates the second blade 59 from the surface of the transfer belt 20 until the predetermined period elapses from the start of use as in the second embodiment. Wear can be suppressed. Therefore, the lifetime of the apparatus can be extended as compared with a conventional cleaning apparatus having two cleaning blades.
In the fourth embodiment, a positive polarity voltage is applied to the second blade 59, but a reverse polarity (minus polarity) voltage may be applied.

Example 5
Next, a fifth example (hereinafter referred to as Example 5) of the belt cleaning device 50 will be described.
FIG. 13 is an enlarged explanatory diagram of the belt cleaning device 50 according to the fifth embodiment.
The belt cleaning device 50 of the fifth embodiment is different from the second embodiment in that both the first blade 56 and the second blade 59 are made of insulating blade members and no voltage is applied to both of the two cleaning blades. To do.
By changing the two cleaning blades from the conductive blade to which the voltage is applied to the insulating blade, the toner removability as the cleaning device is reduced as compared with the configurations of the second to fourth embodiments. Reduce lifespan. However, the belt cleaning device 50 according to the fifth embodiment separates the second blade 59 from the surface of the transfer belt 20 until the predetermined period elapses from the start of use as in the second to fourth embodiments. Unnecessary wear can be suppressed. Therefore, the lifetime of the apparatus can be extended as compared with a conventional cleaning apparatus having two cleaning blades.

Example 6
Next, as Example 6, an example in which the present invention is applied to the photoconductor cleaning device 13 will be described.
FIG. 14 is a schematic explanatory diagram of the photoconductor cleaning device 13 according to the sixth embodiment.
The photoconductor cleaning device 13 in FIG. 14 has substantially the same configuration as the belt cleaning device 50 of the first embodiment described with reference to FIG. 1 except that the object to be cleaned is different. The members denoted by the same reference numerals as those shown in FIG. 1 have the same functions as the members of the belt cleaning device 50.
In the photoconductor cleaning device 13 shown in FIG. 14 as well, the second blade 59 is separated from the surface of the photoconductor 10 as the object to be cleaned until a predetermined period elapses from the start of use as in the first embodiment. Unnecessary wear of the second blade 59 can be suppressed. Therefore, the lifetime of the apparatus can be extended as compared with a conventional cleaning apparatus having two cleaning blades.
In the photoreceptor cleaning device 13 of Example 6, the second blade power supply 67 generates a voltage having a polarity (negative polarity) opposite to the voltage (positive polarity voltage) applied to the first blade 56 by the first blade power supply 55. This configuration is applied to the second blade 59. With such a configuration, the toner whose charging polarity is made positive when passing through the contact position of the first blade 56 is electrostatically attracted to the second blade 59, and the cleaning performance by the second blade 59 is improved. Can be improved.
Further, as shown in FIG. 14, in the photoconductor cleaning device 13, a scattering prevention sponge 68 is disposed between the second blade holder 61 and the casing 51, and toner is scattered from the downstream side of the second blade holder 61. To prevent it.

[Modification 1]
Next, as a first modification, a configuration in which the cleaning device to which the present invention is applied is applied to a one-drum type full-color image forming device will be described.
FIG. 15 is an explanatory diagram of a main part of the printer 100 according to the first modification.
When image formation is performed in the printer 100 of FIG. 15, first, the photosensitive member 10 is rotationally driven in the counterclockwise direction in FIG. 15, and the transfer belt 20 of the intermediate transfer unit 78 is rotationally driven in the clockwise direction in FIG. Then, after uniformly charging the surface of the photoconductor 10 with the charging roller of the charging device 11, the surface of the photoconductor 10 is irradiated with the laser light L modulated with the C image data. An electrostatic latent image for C is formed on the surface. The electrostatic latent image for C is developed with C toner by the developing device 12C. The C toner image thus obtained is primarily transferred onto the transfer belt 20 of the intermediate transfer portion 78. Thereafter, after the transfer residual toner remaining on the surface of the photoconductor 10 is removed by the photoconductor cleaning device 13, the surface of the photoconductor 10 is neutralized by the static elimination lamp 150 and passes through a position facing the light shielding plate 49. Thereafter, the surface of the photoconductor 10 is again uniformly charged by the charging device 11. Next, the surface of the photoconductor 10 is irradiated with laser light L modulated with the M image data to form an M electrostatic latent image on the surface of the photoconductor 10. The electrostatic latent image for M is developed with M toner by the developing device 12M. The M toner image thus obtained is primarily transferred onto the transfer belt 20 so as to overlap the C toner image that has already been primarily transferred onto the transfer belt 20 of the intermediate transfer portion 78. Thereafter, Y and K are also primarily transferred onto the transfer belt 20 in the same manner. The color toner images on the transfer belt 20 that are overlapped with each other in this way are transferred onto the transfer paper P that has been conveyed to the secondary transfer region by the secondary transfer roller 25. The transfer paper P onto which the toner image has been transferred in this way is conveyed by a paper conveyance belt 79 to a fixing unit (not shown). In this fixing unit, the transfer paper P is heated and pressed to fix the toner image on the transfer paper P to the transfer paper P. The fixed transfer paper P is discharged onto a paper discharge tray (not shown). The transfer residual toner remaining on the surface of the photoconductor 10 after the transfer is removed by the photoconductor cleaning device 13. Further, the transfer residual toner remaining on the surface of the transfer belt 20 is removed by the belt cleaning device 50.

The printer 100 shown in FIG. 15 has the same configuration as the belt cleaning device 50 shown in FIG. 1 as the belt cleaning device 50, so that the second blade is used until a predetermined period elapses from the start of use as in the first embodiment. Since 59 is separated from the surface of the transfer belt 20, unnecessary wear of the second blade 59 can be suppressed. As a result, the life of the belt cleaning device 50 can be extended as compared with a conventional cleaning device having two cleaning blades.
In addition, the printer 100 shown in FIG. 15 has the same configuration as the photoconductor cleaning device 13 shown in FIG. 14 as the photoconductor cleaning device 13, so that the predetermined period elapses from the start of use as in the sixth embodiment. Since the second blade 59 is separated from the surface of the photoconductor 10 as the object to be cleaned, unnecessary wear of the second blade 59 can be suppressed. Accordingly, the life of the photosensitive member cleaning device 13 can be extended as compared with a conventional cleaning device having two cleaning blades.

[Modification 2]
Next, as a second modification, a configuration in which the cleaning device to which the present invention is applied is applied to a recording medium conveying member cleaning unit will be described.
FIG. 16 is an explanatory diagram of a main part of the printer 100 according to the second modification.
In the printer 100 shown in FIG. 16, when a paper jam occurs, the toner image on the photoconductor 10 is transferred to the paper conveyance belt 79, and the paper conveyance belt 79 becomes dirty. In addition, a low-charge toner or a positively-charged toner in the developing roller 88 of the developing device 12 may adhere between the papers on the photoreceptor 10. The toner adhering between the papers is transferred to the paper transport belt 79 and stains the paper transport belt 79.
As a paper conveying belt cleaning device 300 for cleaning the paper conveying belt 79, the same configuration as that of the belt cleaning device 50 of the first to fifth embodiments is used. Until the period elapses, the second blade 59 is separated from the surface of the paper conveying belt 79, which is the object to be cleaned, so that unnecessary wear of the second blade 59 can be suppressed. As a result, the paper conveying belt cleaning device 300 can have a longer service life than a conventional cleaning device having two cleaning blades.
In addition, the printer 100 shown in FIG. 16 has the same configuration as the photoconductor cleaning device 13 shown in FIG. 14 as the photoconductor cleaning device 13, so that the predetermined period elapses from the start of use as in the sixth embodiment. Since the second blade 59 is separated from the surface of the photoconductor 10 as the object to be cleaned, unnecessary wear of the second blade 59 can be suppressed. Accordingly, the life of the photosensitive member cleaning device 13 can be extended as compared with a conventional cleaning device having two cleaning blades.

  Further, as shown in FIG. 17, the printer 100 according to the second modification includes a photoconductor 10 as an image carrier and a photoconductor cleaning device 13 that are integrally supported in a frame 83, with respect to the printer 100 main body. The image forming unit 3 may be a detachable image carrier unit. In FIG. 17, in addition to the photoconductor 10 and the photoconductor cleaning device 13, the charging device 11 and the developing device 12 are also integrally supported, but at least the photoconductor 10 and the photoconductor cleaning device 13 are supported. As long as they are integrally supported.

As described above, according to the present embodiment, the belt cleaning device 50 according to the first to fifth embodiments contacts the transfer belt 20 that is a surface-moving object to be cleaned, and removes deposits on the surface of the transfer belt 20. As the cleaning blade, a first blade 56 that is a first cleaning blade disposed on the upstream side in the surface movement direction of the transfer belt 20 and a second blade 59 that is a second cleaning blade disposed on the downstream side in the surface movement direction are used. The first blade 56 is brought into contact with the surface of the transfer belt 20 from the start of use of the belt cleaning device 50, and the second blade 59 is separated from the surface of the transfer belt 20 when use of the belt cleaning device 50 is started. After a predetermined period of time elapses, the second brake at the beginning of use is brought into contact with the surface of the transfer belt 20 by contacting it. 59 and the transfer belt 20 and the second blade 59 in a state where the toner is hardly input to the contact position with the transfer belt 20 and can be prevented from making contact. Thereby, it is possible to suppress the wear of the contact portion from progressing in a state where the second blade 59 hardly contributes to the cleaning of the toner, and it is possible to suppress unnecessary wear of the second blade 59. Therefore, since the wear of the second blade 59 can be prevented from being accelerated and the cleaning performance can be maintained, the life of the belt cleaning device 50 can be extended.
The same applies to the photoconductor cleaning device 13 according to the sixth embodiment and the paper conveyance belt cleaning device 300 according to the second modification, and the life of the cleaning device can be extended.

  Further, as the belt cleaning device 50 of the first embodiment, the first blade 56 and the second blade 59 are made of conductive materials, and the first blade power supply 55 as the first power supply is applied to the first blade 56. A voltage having a polarity opposite to that of the voltage may be applied to the second blade 59 by the second blade power source 67 as the second power source. With such a configuration, the toner having the same charge polarity is electrostatically attracted to the second blade 59 when passing through the contact position of the first blade 56, and the cleaning performance by the second blade 59 is improved. Can be achieved.

  Further, the predetermined period during which the belt cleaning device 50 separates the second blade 59 from the transfer belt 20 is the predetermined time that the surface movement time of the transfer belt 20 from the start of use of the belt cleaning device 50 is predetermined. Due to the period until the second blade 59 is brought into contact with the transfer belt 20 from a state where the wear of the first blade 56 has progressed to some extent and cleaning with the second blade 59 may be required. Unnecessary wear of the two blades 59 can be suppressed.

  Further, a predetermined period during which the belt cleaning device 50 separates the second blade 59 from the transfer belt 20 is a predetermined number of images (the number of images formed by the printer 100 from the start of use of the belt cleaning device 50). 200 [kp]), the second blade 59 is moved to the transfer belt 20 from a state where the wear of the first blade 56 has progressed to some extent and cleaning with the second blade 59 may be required. Since the contact is made, unnecessary wear of the second blade 59 can be suppressed.

  In addition, the photosensitive member 10 as a latent image carrier, the charging device 11 as a charging unit for charging the photosensitive member 10, and the optical unit 4 as a latent image forming unit for forming an electrostatic latent image on the photosensitive member 10. A developing device 12 that is a developing unit that develops the electrostatic latent image on the photoconductor 10 with toner to form a toner image, and a transfer unit that transfers the toner image on the photoconductor 10 to a transfer belt 20 that is a transfer body. In the printer 100 which is an image forming apparatus having the primary transfer roller 24 and a latent image carrier cleaning means for removing the transfer residual toner attached to the surface using the photoreceptor 10 after the transfer as a member to be cleaned, the latent image carrier cleaning is performed. By using the photoconductor cleaning device 13 of Example 6, as a means, the cleaning property of the photoconductor 10 can be improved and the image quality can be improved.

  Further, as in Modification 1, there are provided four developing devices 12 containing toners of different colors as developing means, and a photoconductor provided in the printer 100 in which the four developing devices 12 face one photoconductor 10. By applying the same photoconductor cleaning device 13 as that of the sixth embodiment as the photoconductor cleaning device 13 for cleaning 10, the cleaning property of the photoconductor 10 can be improved and the image quality can be improved.

  Further, as in the sixth embodiment, four developing devices 12 containing toners of different colors are provided as developing means, and the same number of photosensitive members 10 as the three developing devices 12 are provided. By applying the photoconductor cleaning device 13 to which the present invention is applied as the photoconductor cleaning device 13 that cleans the photoconductor 10 having one of the four developing devices 12 facing each other, the cleaning performance of the photoconductor 10 is improved. The image quality can be improved.

  Further, the photoreceptor 10 as an image carrier, the image forming unit 3 as a toner image forming unit for forming a toner image on the photoreceptor 10, and the toner image formed on the photoreceptor 10 as an intermediate transfer member. A primary transfer roller 24 as primary transfer means for primary transfer onto the transfer belt 20; a secondary transfer roller 25 as secondary transfer means for transferring a toner image on the transfer belt 20 onto a transfer paper P as a recording medium; In the printer 100, which is an image forming apparatus having an intermediate transfer member cleaning unit that removes transfer residual toner attached to the surface using the transfer belt 20 after the next transfer as a member to be cleaned, Examples 1 to By using the belt cleaning device 50 of No. 5, the cleaning property of the transfer belt 20 is improved and the image quality can be improved. Further, when the toner images formed on the surfaces of the plurality of photoconductors 10 are superposed on the transfer belt 20 as in the printer 100, the toner used to form the toner images on the photoconductors 10 has other colors. It is possible to prevent the color mixture of the toner adhering to the photosensitive member 10 and mixing the toner colors.

  Further, the photosensitive member 10 as an image carrier, the developing device 12 constituting toner image forming means for forming a toner image on the photosensitive member 10, and the toner image formed on the photosensitive member 10 at the transfer position are recorded on the recording medium. A transfer roller 45 which is a transfer means for transferring to the transfer paper, a fixing means (not shown) for fixing the toner image on the transfer paper on which the toner image is transferred, and a transfer paper from the transfer position to the fixing position. An image forming apparatus having a paper conveyance belt 79 as a recording medium conveyance member carried and conveyed, and a recording medium conveyance member cleaning unit that removes unnecessary toner attached to the surface using the paper conveyance belt 79 as a member to be cleaned. In the printer 100 according to the second modified example, the paper conveying belt cleaning device 300 according to the second modified example is used as the recording medium conveying member cleaning unit, so that the paper conveying belt is used. 9 cleanability can be prevented backside contamination of a transfer paper is improved.

Further, by using the photosensitive member 10 of the printer 100 having a photosensitive layer made of amorphous silicon, the amount of film scraping of the photosensitive member 10 can be reduced.
Further, by using a photoconductor 10 provided in the printer 100 made of a material in which a filler is dispersed, the film scraping amount of the photoconductor 10 can be reduced.
Further, by using an organic photoconductor having at least one of a photoconductor using a cross-linked charge transport material or a photoconductor having a surface layer reinforced with a filler as the photoconductor 10, The amount of film scraping can be reduced.

Further, as a toner used for forming a toner image in the printer 100, a toner having a shape factor SF-1 in the range of 100 to 150 can be used to improve the image quality.
In addition, the image forming unit 3 that is an image carrier unit that is detachably attached to the main body of the printer 100 by integrally supporting the photoconductor 10 that is an image carrier that is a member to be cleaned and at least the photoconductor cleaning device 13. Thereby, the operability when replacing the members constituting the image forming unit 3 is improved.

DESCRIPTION OF SYMBOLS 1 Device main body 2 Paper feed cassette 3 Image forming unit 4 Optical unit 5 Intermediate transfer unit 6 Fixing device 7 Toner bottle 8 Paper discharge tray 10 Photoconductor 11 Charging device 12 Developing device 13 Photoconductor cleaning device 20 Transfer belt 21 Drive roller 22 Tension Roller 23 driven roller 24 primary transfer roller 25 secondary transfer roller 27 paper feed roller 28 registration roller pair 29 discharge roller 45 transfer roller 49 light shielding plate 50 belt cleaning device 51 casing 53 inlet seal 54 first blade shaft 55 first blade power source 56 First blade 56t Contact point 57 First blade pressure spring 58 First blade holder 59 Second blade 61 Second blade holder 62 Toner discharge coil 63 Toner discharge guide 64 Second blade shaft 65 Contact / separation cam 65a Second blade contact / separation Mechanism 66 Second blade pressure spring 67 Second blade power supply 68 Spattering prevention sponge 69 Application brush 70 Lubricant supply device 71 Solid lubricant 72 Lubricant pressure spring 78 Intermediate transfer portion 79 Paper transport belt 83 Frame body 88 Development roller 100 Printer 150 Static elimination lamp 200 Control unit 300 Paper transport belt cleaning device 500 a-Si photoconductor 501 Support 502 Photoconductive layer 503 Amorphous silicon surface layer 504 Amorphous silicon charge injection blocking layer 505 Charge generation layer 506 Charge transport layer P Transfer paper

JP 61-251887 A Japanese Patent Laid-Open No. 05-341696

Claims (14)

A first cleaning blade arranged on the upstream side of the surface movement direction of the object to be cleaned as a cleaning blade that comes into contact with the object to be cleaned and moves on the surface of the object to be cleaned, and a surface movement direction In a cleaning device having a second cleaning blade disposed on the downstream side,
The first cleaning blade is brought into contact with the surface of the object to be cleaned from the start of use of the cleaning device,
The second cleaning blade is separated from the surface of the object to be cleaned at the start of use of the cleaning apparatus, and is brought into contact with the surface of the object to be cleaned after a predetermined period has elapsed since the start of use. The cleaning device according to claim 1.
The first cleaning blade and the second cleaning blade are made of a conductive material,
A first power source for applying a voltage to the first cleaning blade;
A cleaning apparatus comprising: a second power source that applies a voltage having a polarity opposite to a voltage applied to the first cleaning blade by the first power source to the second cleaning blade. The cleaning device according to claim 1 or 2,
The cleaning apparatus according to claim 1, wherein the predetermined period is a period from when the use of the cleaning apparatus starts until the surface movement time of the object to be cleaned reaches a predetermined time. The cleaning device according to claim 1, 2 or 3,
The object to be cleaned is a surface moving body that is disposed in an image forming apparatus and to which toner can adhere,
The cleaning apparatus according to claim 1, wherein the predetermined period is a period from the start of use until the number of images formed on the image forming apparatus reaches a predetermined number. A latent image carrier;
Charging means for charging the latent image carrier;
Latent image forming means for forming an electrostatic latent image on the latent image carrier;
Developing means for developing an electrostatic latent image on the latent image carrier with toner to form a toner image;
Transfer means for transferring the toner image on the latent image carrier to a transfer body or a recording medium;
In the image forming apparatus having a latent image carrier cleaning means for removing the transfer residual toner attached to the surface using the latent image carrier after the transfer as a cleaning target,
An image forming apparatus using the cleaning device according to claim 1, 2, 3, or 4 as the latent image carrier cleaning means. The image forming apparatus according to claim 5.
A plurality of developing devices each containing different colors of toner as the developing means;
An image forming apparatus, wherein the plurality of developing devices face one latent image carrier. The image forming apparatus according to claim 5.
A plurality of developing devices each containing different colors of toner as the developing means;
Including the same number of latent image carriers as the plurality of developing devices;
An image forming apparatus, wherein one of the plurality of developing devices faces one latent image carrier. An image carrier;
Toner image forming means for forming a toner image on the image carrier;
Primary transfer means for primarily transferring a toner image formed on the image carrier to an intermediate transfer body;
Secondary transfer means for transferring the toner image on the intermediate transfer member to a transfer member or a recording medium;
In an image forming apparatus having an intermediate transfer body cleaning unit that removes transfer residual toner adhering to the surface using the intermediate transfer body after secondary transfer as a body to be cleaned,
An image forming apparatus using the cleaning device according to claim 1, 2, 3, or 4 as the intermediate transfer member cleaning means. An image carrier;
Toner image forming means for forming a toner image on the image carrier;
Transfer means for transferring a toner image formed on the image carrier to a recording medium at a transfer position;
Fixing means for fixing the toner image at a fixing position on the recording medium onto which the toner image has been transferred;
A recording medium conveying member that carries and conveys a recording medium from the transfer position to the fixing position;
In an image forming apparatus having a recording medium conveying member cleaning unit that removes unnecessary toner attached to the surface using the recording medium conveying member as a member to be cleaned,
An image forming apparatus using the cleaning device according to claim 1 as a recording medium conveying member cleaning unit. The image forming apparatus according to claim 5, 6 or 7.
An image forming apparatus characterized in that a photosensitive layer made of amorphous silicon is used as the latent image carrier. The image forming apparatus according to claim 5, 6 or 7.
An image forming apparatus, wherein the latent image carrier is made of a material in which a filler is dispersed. The image forming apparatus according to claim 5, 6 or 7.
As the latent image carrier, an organic photoconductor having at least one of a photoconductor using a cross-linked charge transport material or a photoconductor having a surface layer reinforced with a filler is used. Image forming apparatus. The image forming apparatus according to claim 5,
An image forming apparatus using a toner having a shape factor SF-1 in the range of 100 to 150 as the toner used for forming the toner image. In an image carrier unit that integrally supports an image carrier that is a member to be cleaned and a cleaning unit that cleans at least the surface of the image carrier, and is detachable from the image forming apparatus main body.
An image carrier unit using the cleaning device according to claim 1, 2, 3, or 4 as the cleaning means.

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