JP2014202949A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus that can perform filming removal processing while reducing a burden on maintenance without deteriorating durability of an intermediate transfer belt.SOLUTION: A printer 100 includes an attachment part 170 to which a filming removal unit 7 removing filming materials can be attached. The printer 100 has the filming removal unit 7 attached to the attachment part 170 only during filming removal processing, and revolves an intermediate transfer belt 25 while inhibiting image forming operation to perform the sequence of the filming removal processing.

Description

  The present invention relates to an image forming apparatus, and more particularly to a technique for removing a filming substance attached to an image carrying surface of an image carrying rotating body in the image forming apparatus.

  As an electrophotographic color image forming apparatus, a plurality of image forming units having different development colors are arranged in a line along the traveling direction of a rotating intermediate transfer belt, and toners of each development color formed by the image forming units There is a so-called tandem type image forming apparatus configured to form a color toner image by performing multiple transfer on an intermediate transfer belt to form a color toner image and then performing secondary transfer on a recording sheet.

In the image forming apparatus configured as described above, it is difficult to completely transfer the toner image formed on the intermediate transfer belt onto the recording sheet by secondary transfer, and the toner that could not be transferred remains on the intermediate transfer belt. There is.
Since such residual toner adversely affects the next image formation, a belt cleaner having a cleaning blade and a cleaning brush is usually disposed in the middle of the circulation path of the intermediate transfer belt to remove the residual toner. ing.

However, toner, toner external additives, or paper dust (especially the amount of paper dust) in the recording sheet partially adheres to the surface of the intermediate transfer belt and cannot be removed with a normal belt cleaner. (Hereinafter, the substance fixed in the form of a film on the surface of the intermediate transfer belt is referred to as “filming substance”).
When such a filming material is laminated on the surface of the intermediate transfer belt, the electric resistance in the thickness direction of the belt at the laminated portion increases, and the transfer efficiency with other portions is different, resulting in image unevenness. There is a fear.

It is possible to remove the above filming substances by using a cleaning blade as a belt cleaner, increasing its pressing force and applying a large elastic force to the intermediate transfer belt. As a result, the durability of the intermediate transfer belt and the cleaning blade is significantly deteriorated, and the maintenance cost is increased.
On the other hand, it is known that the filming substance is easily removed by wiping with a cleaning member containing a liquid such as water or alcohol. For example, in Patent Document 1, a cleaning position of a belt cleaner formed of a cleaning brush is known. Filming removal that wipes the filming substance by bringing the cleaning roller impregnated with liquid into contact with the transfer belt until it reaches the primary transfer position in the image forming unit, downstream of the running direction of the intermediate transfer belt. A configuration in which devices are arranged has been proposed. According to this method, the filming substance can be removed without deteriorating the durability of the intermediate transfer belt.

JP 2012-22257 A JP 2002-296922 A JP 2002-302285 A

However, in the method according to Patent Document 1, a predetermined time is required for laminating until the filming substance affects the image quality, and it is not always necessary to clean the film frequently. Since it is wiped off, it is necessary to replenish the cleaning liquid frequently, which takes time for maintenance and places a heavy burden on the user.
Furthermore, since the intermediate transfer belt is wiped off with liquid during the image forming operation, the liquid adhering to the intermediate transfer belt moves to the photosensitive drum side at the primary transfer position and the charging characteristic of the photosensitive drum deteriorates, and the image quality deteriorates. There is also a risk.

Such problems relating to filming removal can occur in common in image forming apparatuses having an image bearing rotating body such as an intermediate transfer belt and an intermediate transfer drum, regardless of whether the color is monochrome or monochrome.
The present invention has been made in view of the above circumstances, and does not impair the durability of the image bearing rotating body, reduces the maintenance burden on the user, and prevents the filming substance from being deteriorated. An object of the present invention is to provide an image forming apparatus that can be removed.

  In order to achieve the above object, an image forming apparatus according to the present invention forms a toner image by an image forming unit on an image carrying surface of a rotating image carrying rotary body, and records the toner image formed on the image carrying surface. An image forming apparatus for transferring an image onto a sheet to form an image, wherein the filming removal unit for removing the filming material attached to the image carrying surface of the image carrying rotating body is detachable; and When a filming removal unit is mounted on the mounting portion, the image carrier rotating body circulates in a state where there is no toner image forming operation by the image forming unit, and the filming removal operation is performed by the filming removal unit. And a control means for making it possible.

  According to the present invention, the image forming means includes a photoconductor unit having a photosensitive rotator, and at least the photoconductor unit of the image forming means is configured to be detachable from the apparatus main body, and The filming removal unit is configured to be mounted in place of at least the photosensitive unit, and the mounting unit for mounting at least the photosensitive unit is shared as the mounting unit for mounting the filming removal unit. It may be.

Here, the filming removal unit has a rotating body that receives a driving force from the apparatus main body and rotates. When the filming removal unit is attached to the apparatus main body instead of at least the photosensitive unit, the photosensitive unit rotates. It is good also as providing the power transmission means connected with the drive shaft of the same drive source as the drive source which drives a body, and transmitting the driving force to the said rotary body.
The present invention further includes a toner cleaning unit that cleans residual toner on the image bearing surface of the image bearing rotator so as to be detachable from the apparatus main body, and the filming removal unit is mounted in place of the toner cleaning unit. The mounting portion for mounting the toner cleaning unit may be shared as the mounting portion for mounting the filming removal unit.

  Here, each of the toner cleaning unit and the filming removal unit has a rotating body that rotates by receiving a driving force from the apparatus main body, and the filming removal unit is installed in the apparatus main body instead of the toner cleaning unit. A power transmission means may be provided which is connected to a drive shaft of the same drive source as the drive source for driving the toner cleaning unit and receives a drive force when mounted.

The filming removal unit may be configured to remove the filming material by sliding a filming removal member impregnated with a filming removal liquid against the image bearing surface. .
Here, the filming removal unit is located between the position where the filming removal unit is mounted and the position downstream of the image carrying surface in the traveling direction and the position where the photosensitive rotating body of the photosensitive unit is in contact. Thus, a separate mounting portion to which a liquid removal unit for removing the liquid adhering to the image carrying surface may be mounted may be provided.

Further, here, the liquid removing unit may be configured to absorb and remove the liquid adhering to the image carrying surface by bringing the liquid absorbing member into contact with the image carrying surface of the image carrying rotating body. .
Here, the liquid absorbing member is a cloth belt, and the cloth belt is moved while the cloth belt is moved while the cloth belt wound in a roll is wound with another roller. It may be configured to contact the carrying surface.

Further, the liquid removing unit may be configured to scrape and remove the liquid adhering to the image carrying surface by bringing the tip of the blade into contact with the image carrying surface of the image carrying rotating body. Good.
In addition, the filming removing unit rotates the image bearing surface in a running direction and a counter direction with a roller having a roughened peripheral surface in contact with the image bearing surface of the image bearing rotator. The structure which removes a ming substance may be sufficient.

The filming removal unit may be configured to scrape the filming substance by pressing the blade with a predetermined pressing force on the image carrying surface of the image carrying rotating body.
The filming removing unit includes a first unit including an impregnation unit that impregnates the filming removing member with a predetermined liquid when the cloth-like filming removing member wound in a roll shape is pulled out. A second unit having a winding unit that winds up the cloth-like filming removal member from the first unit, and the filming removal member reaches the second unit from the first unit. In the meantime, the filming substance may be removed by rubbing against the image carrying surface.

In addition, mounting portions for mounting the filming removal unit are provided at a plurality of locations along the circular trajectory of the image bearing surface of the image bearing rotating body, and a plurality of filming removals of the same type or different types are provided. The unit may be attachable to each attachment portion.
The image forming unit may include a plurality of photoconductor units that form toner images of a plurality of colors, and at least one photoconductor unit may be replaced with a filming removal unit.

  The image forming means includes a plurality of photoconductor units that form toner images of a plurality of colors, and other photoconductor units excluding the photoconductor unit on the most downstream side in the running direction of the image carrying surface of the image carrying rotor. At least one of the photoconductor units is replaceable with the filming removal unit, and at least one photoconductor unit on the downstream side in the running direction of the image carrying surface with respect to the photoconductor unit to be replaced with the filming removal unit. The liquid removal unit may be replaceable.

Here, it is assumed that there is provided separation means for relatively separating the photosensitive rotating body of the photosensitive unit that has not been replaced with another unit during the filming removal operation from the image bearing surface of the image bearing rotating body. Also good.
Here, among the plurality of photosensitive units, the photosensitive unit replaced with another unit may include a photosensitive unit that forms a black toner image.

  According to the above invention, since the filming removal unit is configured to be detachable from the apparatus main body, the filming removal unit is attached to the image forming apparatus only when the filming removal process is necessary, and the filming removal process is executed. As in the prior art, for example, there is no risk of impairing the durability of the image bearing rotator by applying an excessive shear force to the image bearing rotator at all times by means of a blade, for example. Further, even when the filming removal method using liquid as in Patent Document 1 is used, it is only necessary to replenish the liquid only when the filming removal unit is mounted and the filming removal process is executed. The effort is greatly reduced.

  Further, since the filming removal process by the filming removal unit is executed in a state where the image forming operation is not executed, the image quality is deteriorated by executing the filming removing process simultaneously with the image forming operation as in the conventional case. There is no negative effect.

It is a figure which shows a structure when the filming removal unit is mounted | worn with the printer which concerns on Embodiment 1 of this invention. (A) is a schematic sectional drawing which shows the structure of the photoconductor unit which can be attached or detached to the said printer, (b) is a figure which shows a mode that the said photoconductor unit is mounted | worn to a printer main body. (A) is a schematic sectional drawing which shows the structure of the filming removal unit which can be attached or detached to the said printer, (b) is a figure which shows a mode that the said filming removal unit is mounted | worn with a printer main body. It is a figure which shows the structure of the control part of a printer. It is a flowchart which shows the control content of the filming removal process performed by the said control part. It is a figure which shows the structure of the principal part when the filming removal unit is mounted | worn with the printer which concerns on Embodiment 2 of this invention. (A) is a schematic sectional drawing which shows the structure of the filming removal unit which can be attached or detached to the printer which concerns on the said Embodiment 2, (b) is a mode that the said filming removal unit is mounted | worn to a printer main body. FIG. (A) (b) is a figure which shows roughly the principal part of the printer which concerns on the structures 1 and 2 as a modification in this invention, respectively. (A) is a figure which shows schematically the printer which concerns on the structure 3 corresponded to Embodiment 1, and (b) shows the printer which concerns on the structure 4 as the modification, respectively. (A) (b) is a figure which shows roughly the principal part of the printer which concerns on the structures 5 and 6 as a modification in this invention, respectively. (A) is a figure which shows schematically the printer which concerns on the structure 7 equivalent to Embodiment 2, and (b) respectively shows the printer which concerns on the structure 8 as the modification. (A) (b) is a figure which shows roughly the principal part of the printer which concerns on the structures 9 and 10 as a modification in this invention, respectively. (A) is a figure which shows roughly the printer which concerns on the structure 11 as a modification in this invention, (b) is a figure which shows schematically the printer by which the conventional filming removal unit is not mounted | worn as a comparative example. It is. It is the schematic which shows the structure of the liquid removal unit which can be mounted | worn with the printer which concerns on the structure 4 of FIG.9 (b). It is the schematic which shows the structure of the division | segmentation type filming removal unit which can be mounted | worn with the printer which concerns on the structure 11 of Fig.13 (a). FIGS. 11A and 11B are schematic diagrams illustrating the configuration and operation of a belt separation mechanism in the printer according to configuration 8 in FIG. It is a table | surface which shows the result in the evaluation experiment of the filming removal process in each structural example and a comparative example.

<Embodiment 1>
Hereinafter, an embodiment of an image forming apparatus according to the present invention will be described by taking as an example a case where it is applied to a tandem color printer (hereinafter simply referred to as “printer”).
(1) Configuration of Printer FIG. 1 is a diagram illustrating a configuration of a printer 100 according to the present embodiment.

As shown in FIG. 1, the printer 100 includes an image process unit 1, an intermediate transfer unit 2, a paper feed unit 3, a fixing unit 4, a control unit 5, and the like.
When the printer 100 is connectable to a network (for example, a LAN) and receives a print job from an external terminal device (not shown) via the network, each of the colors of yellow, magenta, cyan, and black is received according to the print conditions. A toner image is formed, and these are transferred onto a recording sheet in multiple to form a color image. Hereinafter, the reproduction colors of yellow, magenta, cyan, and black are expressed as Y, M, C, and K, and Y, M, C, and K are added as subscripts to the numbers of the components related to the reproduction colors.

The image processing unit 1 includes image forming units 10 </ b> Y, 10 </ b> M, 10 </ b> C, and 10 </ b> K arranged in the vertical direction along the traveling surface of the intermediate transfer belt 25.
Each of the image forming units 10Y to 10K includes photoconductor units 11Y to 11K, exposure units 12Y to 12K, and developing units 13Y to 13K.
Among the photoconductor units 11Y to 11K, for example, as shown in the schematic cross-sectional view of FIG. 2A, the photoconductor unit 11K includes a photoconductor drum 111K, a charging charger 112K, a cleaning blade 113K, and the like mounted on a housing 116K. It becomes.

A coupling member 111Ka (see FIG. 2 (b)) is attached as a power transmission means to the rotating shaft of the photosensitive drum 111K on the far side in the axial direction.
When the maintenance door (not shown) on the front side of the printer 100 is opened and the filming removal unit 7 is inserted and mounted along the rails 104 and 105 held by the main frame 103 inside the printer 100, the power The transmission coupling member 111K engages with the coupling member 117Kb attached to the drive shaft 117Ka of the drive motor 117K disposed on the apparatus main body side, receives a rotational driving force from the printer 100 main body side, and receives an image. At the time of formation, it is rotationally driven in the arrow direction (counterclockwise) in FIG.

In such a configuration, the residual toner on the photosensitive surface of the peripheral surface of the photosensitive drum 111K is scraped off by the cleaning blade 113K, and then uniformly charged to a predetermined potential by the charging charger 112K, and then the exposure unit 12K. An electrostatic latent image is formed upon exposure scanning according to FIG.
The electrostatic latent image formed on the photosensitive drum 111K is supplied with black toner from the developing unit 13K and is visualized as a toner image, and this toner image is applied to the primary transfer roller 14K (FIG. 1). In response to the electrostatic force generated by the transfer voltage, the image is transferred onto the intermediate transfer belt 25.

  In FIG. 2A, the toner scraped off by the cleaning blade 113K falls into the waste toner reservoir 114K, and is parallel to the rotational axis of the photosensitive drum 111K of the photosensitive unit 11K by the screw 115K that is driven to rotate. In this direction, the toner is conveyed toward an opening formed at one end in a certain direction and collected in a waste toner box (not shown). The screw 115K is rotationally driven by transmitting the rotational force of the photosensitive drum 111K to a rotating shaft 115Ka of the screw 115K via a gear (not shown). However, a coupling member may also be provided at the end of the rotating shaft 115Ka so as to receive a driving force directly from the apparatus main body side.

  Returning to FIG. 1, the other image forming units 10Y to 10C have the same configuration as that of the image forming unit 10K except that the toner color is different. The toner images are formed at different timings, and are superimposed and transferred at the same position on the intermediate transfer belt 25 of the intermediate transfer unit 2 to form a color toner image.

The intermediate transfer unit 2 is formed by stretching the endless intermediate transfer belt 25 on the driving roller 21 and the driven rollers 22 to 24, and the intermediate transfer belt 25 is positioned at a position facing the photosensitive drums 111 Y to 111 K. Primary transfer rollers 14Y to 14K are provided.
From the secondary transfer position 26 of the intermediate transfer belt 25 (the position where the drive roller 21 and the secondary transfer roller 35 are close to each other), the downstream side in the belt traveling direction (hereinafter, the downstream side and the upstream side in the belt traveling direction are simply “ A belt cleaner 6 and a filming removal unit 7 are disposed along the intermediate transfer belt 25 at positions “downstream” and “upstream”).

The belt cleaner 6 is for removing residual toner on the intermediate transfer belt 25 that has not been completely transferred onto the recording sheet by the secondary transfer roller 35 and cleaning the belt.
The filming removal unit 7 is configured to be mounted on the mounting portion 170 of the main body of the printer 100 when removing the filming material attached to the transfer surface of the intermediate transfer belt 25.

Specific configurations of the belt cleaner 6 and the filming removal unit 7 will be described later.
The paper feeding unit 3 includes a paper feeding cassette 31 that stores recording sheets, a feeding roller 32 that feeds the recording sheets in the paper feeding cassette 31 one by one, a rolling roller 33 that rolls out the fed recording sheets, and a timing roller 34. Etc.

The timing roller 34 conveys the recording sheet to the secondary transfer position 26 in synchronization with the timing at which the color toner image primarily transferred onto the intermediate transfer belt 25 is conveyed to the secondary transfer position 26.
Then, at the secondary transfer position 26, the color toner images on the intermediate transfer belt 25 are collectively transferred onto the recording sheet by the action of the transfer voltage applied to the secondary transfer roller 35.

The recording sheet on which the toner image is secondarily transferred is further conveyed to the fixing unit 4, and the toner image (unfixed image) on the recording sheet is heated and pressed in the fixing unit 4 and thermally fixed on the recording sheet. Thereafter, the paper is discharged onto a paper discharge tray 37 by a discharge roller 36.
Note that, when printing a monochrome image, only the image forming unit 10K of the four image forming units is operated.

The control unit 5 controls the image processing unit 1, the intermediate transfer unit 2, the paper feeding unit 3, and the fixing unit 4 in a unified manner to execute a smooth printing operation.
(2) Configuration of Belt Cleaner The belt cleaner 6 includes first and second cleaning units 6 a and 6 b along the intermediate transfer belt 25 on the downstream side of the secondary transfer position 26.

  The first and second cleaning units 6a and 6b are respectively contacted with the transfer surface of the intermediate transfer belt 25 to scrape residual toner and a recovery roller 63 that recovers toner scraped by the brush roller 62. And a blade 64 that scrapes off the toner adhering to the surface of the collection roller 63 and a counter roller 61 that is disposed to face the brush roller 62 with the intermediate transfer belt 25 interposed therebetween.

The counter roller 61 and the collection roller 63 in the first cleaning unit 6a are respectively applied with negative and positive potentials by the cleaning power source 64a, and are negatively charged on the intermediate transfer belt 25 by the electric field generated thereby. Residual toner remaining is collected.
On the other hand, a positively charged toner is recovered by applying a voltage having a reverse potential to the opposing roller 61 and the recovery roller 63 in the second cleaning unit 6b by a cleaning power source 64b.

In this example, a brush roller is used as the belt cleaner 6 to collect residual toner on the photosensitive drum by electrostatic force. However, the configuration is not limited to this. Even a simple configuration using a rubber blade as in the prior art can be applied as long as the pressing force does not significantly affect the durability of the intermediate transfer belt.
(3) Configuration of Filming Removal Unit At a position downstream of the belt cleaner 6 along the intermediate transfer belt 25, the filming removal unit 7 is detachably attached to the mounting portion 170 of the printer 100 main body. Although it is not mounted during a normal printing operation, when it is necessary to remove the filming material attached to the transfer surface of the intermediate transfer belt 25, the printer 100 is mounted and operated.

FIG. 3A is a schematic cross-sectional view showing the configuration of the filming removal unit 7.
As shown in the figure, the filming removing unit 7 includes a non-woven fabric supply roller 71 in which a non-woven fabric (cloth-like belt) 72 made of, for example, rayon fiber is wound around a housing 79, a liquid impregnation roller 73, The application roller 74 and the nonwoven fabric winding roller 75 are rotatably supported.

The non-woven fabric 72 drawn out from the non-woven fabric supply roller 71 is wound around the lower side of the liquid-impregnating roller 73 and the upper side of the application roller 74 and then wound up by the non-woven fabric winding roller 75. Yes.
The nonwoven fabric 72 comes into contact with the liquid supply pad 77 urged toward the liquid impregnation roller 73 from below by an elastic member such as a spring 78 at a position wound around the liquid impregnation roller 73.

The liquid supply pad 77 is formed of, for example, felt, and the lower part thereof is immersed in the film removal liquid 76a filled in the liquid reservoir 76, and the contact surface with the nonwoven fabric 72 is wetted by capillary action. The liquid is supplied in contact with the nonwoven fabric 72.
As such a filming removal liquid, alcohol, water, or the like can be used, and ethanol is used in the present embodiment.

The non-woven fabric 72 is a portion wound around the coating roller 74, wipes the filming substance by sliding in contact with the intermediate transfer belt 25 in the counter direction, and then wound up by the non-woven fabric winding roller 75.
A coupling member 751 for power transmission is attached to the rotating shaft of the nonwoven fabric winding roller 75 on the far side in the axial direction (see FIG. 3B).

  When the maintenance door (not shown) on the front side of the printer 100 is opened and the filming removal unit 7 is inserted and mounted along the rails 101 and 102 held by the main frame 103 inside the printer 100, the power The transmission coupling member 751 engages with a coupling member connected to a drive source (not shown) disposed on the printer 100 main body side in the same manner as described in FIG. The driving force is supplied from the side.

  Hereinafter, in the present specification, the “mounting portion” of the unit in the printer 100 specifically refers to a space for mounting the unit, and guides and installs the unit to an installation position in the space such as a guide rail. And a driving source that supplies driving force by connecting to the rotating shaft of the rotating body in the unit when the unit is mounted (when the driving force is necessary for the unit to perform its function).

  When the filming removal unit 7 is mounted on the mounting unit 170 of the printer 100, a counter roller 701 whose outer peripheral layer is made of an elastic material is disposed at a position facing the coating roller 74 and the intermediate transfer belt 25. The intermediate transfer belt 25 is supported from the back surface so that the contact pressure between the nonwoven fabric 72 wound around the application roller 74 and the intermediate transfer belt 25 becomes a predetermined value or more.

(4) Configuration of Control Unit FIG. 4 is a block diagram illustrating a relationship between a specific configuration of the control unit 5 and main components to be controlled by the control unit 5.
As shown in the figure, the control unit 5 includes a CPU 51, a communication interface (I / F) unit 52, a RAM 53, a ROM 54, and an EEPROM (hereinafter, “registered trademark”) 55 which is a nonvolatile memory.

The communication I / F unit 52 is an interface for connecting to a LAN such as a LAN card or a LAN board.
The ROM 54 is a storage that stores various programs executed by the CPU 51. The RAM 53 serves as a work area when the CPU 51 executes the program.
The EEPROM 55 stores information necessary for maintenance such as a cumulative value of the number of printers.

The CPU 51 reads a necessary program from the ROM 54, controls the image processing unit 1, the intermediate transfer unit 2, the paper feeding unit 3, the fixing unit 4 and the like uniformly to execute a smooth printing operation and remove filming. When the unit 7 is mounted, the filming removal processing sequence is executed.
The operation panel 8 is provided at an easy-to-operate position on the upper front of the printer 100. The operation panel 8 includes a display unit including a plurality of input keys and a liquid crystal panel. A touch panel is laminated on the surface of the display unit. An instruction from the user is accepted by touch input from the touch panel or key input from an input key.

(5) Sequence of Filming Removal Process As described above, the filming removal unit 7 is configured to be detachable from the printer 100.
The removal of the filming material does not need to be performed frequently. The filming material may be removed when the degree of lamination of the filming material on the intermediate transfer belt 25 affects the image quality. This is because it is sufficient to attach the unit 7 and execute the filming removal process.

Normally, the printer 100 used in the workplace has a large number of prints, so a maintenance contract is concluded with a maintenance company, and the maintenance company's request is periodically or when the image quality deteriorates, according to the user's request. It is sufficient if the service person performs the filming removal process.
Therefore, in the present embodiment, in the printer 100, the filming removal unit 7 is detachable, while the filming removal processing sequence can be executed when the filming removal unit 7 is attached. The service person can carry the filming removal unit 7 as a part of the maintenance service, and can perform the filming removal process as necessary.

FIG. 5 is a flowchart showing a filming removal process sequence executed by the control unit 5 after receiving an instruction to execute a filming removal process from a serviceman or the like.
First, it is determined whether an instruction for filming removal processing has been received from the operation panel 8 (step S101).
In this case, a service person or the like may input the password from the operation panel 8 to log in and display a setting screen for maintenance, and then instruct the filming removal process, or the printer A dedicated switch may be provided inside 100 and an instruction may be given by operating this switch.

If an instruction to execute the filming removal process is received via these receiving means (YES in step S101), the control unit 5 then attaches the filming removal unit 7 to the mounting unit. It is determined whether or not.
As shown in FIG. 3B, a filming removal unit detection unit 7b is disposed in the vicinity of the opening in the filming removal unit 7 mounting portion of the main frame 103 of the main body of the printer 100. Based on the detection signal, The control unit 5 performs the determination in step S102.

The filming removal unit detection unit 7b may be a reflection type or transmission type photoelectric sensor that detects the hung 79 of the filming removal unit 7, or may be a part of the hung 79 of the filming removal unit 7 when attached. A simple switch such as a limit switch that switches to ON (or OFF) upon contact with the actuator may be used.
Further, when an IC tag that stores the type, serial number, usage history, etc. of the unit is attached to the filming removal unit 7, such as an IC tag reader that reads out the stored contents of the IC tag. It may be a thing.

If it is determined that the filming removal unit 7 has not been mounted yet (NO in step S102), the process proceeds to step S108, and an error message is displayed on the liquid crystal display unit of the operation panel 8 so that the operator The installation of the filming removal unit 7 is urged to end the sequence once.
If it is determined in step S102 that the filming removal unit 7 is mounted (YES in step S102), the developing unit 13Y to 13K is set to a state in which the printing operation is not performed. The developing bias applied to the developing roller is turned off, and a predetermined voltage is applied to the charging chargers 112Y to 112K to charge the surface potential to a negative potential. Further, the operations of the exposure units 12Y to 12K are turned off (polygon mirror rotation stop and laser diode light emission are turned off) (step S103).

In the above state, the intermediate transfer belt 25 is run, the photosensitive drums 111Y to 111K are rotated, and the power source of the driving source of the filming removal unit 7 is turned on (step S104).
When the intermediate transfer belt 25 rotates a preset number of times (N times) (YES in step S105), it is determined that the filming removal process has been completed, and the charging charger is turned off. The running of the intermediate transfer belt 25 and the rotation of the photosensitive drum are stopped.

  The value of “N” is obtained in advance through experiments or the like as the number of times required for completely removing the filming material on the intermediate transfer belt 25 by the filming removal unit 7 and stored in the ROM 54. When ethanol is used as the impregnating liquid for the nonwoven fabric 72 as in the present embodiment and the intermediate transfer belt 25 is wound in the running direction and the counter direction, for example, at a speed of 0.1 mm / sec, “N”. Is set to a value between about 5 and 10, and the filming removal process does not take much time.

  The rotation number of the intermediate transfer belt 25 is counted by, for example, attaching an appropriate mark indicating the home position to an area that does not contribute to image formation at the end in the width direction of the intermediate transfer belt 25. This can be performed by detecting with the photoelectric sensor or the like and counting the number of detections with the control unit 5. Alternatively, an encoder is attached to the drive shaft of the drive source of the intermediate transfer belt 25 and the number of encoder pulses is counted. If the drive source is a stepping motor, the number of drive pulses is counted and the intermediate transfer belt is counted. You may make it rotate until it reaches the count number equivalent to 25 N rotation.

When the intermediate transfer belt 25 rotates N times and stops, a message indicating that the filming removal process has been completed is displayed on the display unit of the operation panel 8 (step S107), and the filming removal process sequence is completed. .
Thereafter, the service person removes the filming removal unit 7 from the printer 100, performs other maintenance as necessary, and closes the front door for maintenance after the printing operation can be performed.

As described above, in the filming removal process according to the present embodiment, when the filming removal process is necessary, the serviceman carries the filming removal unit 7 and when the filming removal process is necessary, the printer The filming removal unit 7 is attached to 100 and the filming removal processing sequence is executed.
As a result, it is not necessary to equip the printer 100 with the filming removal unit 7 as a standard feature, and not only can the manufacturing cost of the printer 100 be reduced, but also the replacement of the nonwoven fabric supply roller 71 and the removal of the filming liquid. There is no need for the user to perform replenishment and the like, and the burden of maintenance on the user side is eliminated.

Further, since the filming removal processing sequence is executed in a state where the printing operation is not executed, there is no situation where the image is deteriorated due to the influence of the filming removal processing.
<Embodiment 2>
In the first embodiment, a filming removal unit 7 is provided on the downstream side of the belt cleaner 6 and the filming removal unit 7 is attached to this part as necessary to perform the filming removal process. However, the second embodiment is different in that the image forming unit 10K is detached from the mounting portion of the image forming unit 10K and the filming removal unit can be mounted.

  FIG. 6 is a diagram showing the main parts of the image processing unit 1 and the intermediate transfer unit 2 of the printer 100 according to the second embodiment. The filming removal unit 70 is used in place of the photoconductor unit 11K of the image forming unit 10K. Shows a state where is attached. In the drawing, for the sake of convenience, among the image forming units 10K, the one in which the photosensitive unit 11K and the developing unit 13K are also removed is disclosed, but at least only the photosensitive unit 11K is removed, and the filming removal unit 70 is removed. Any configuration may be used.

  FIG. 7A is a schematic cross-sectional view showing the configuration of the filming removal unit 70. The filming removal unit 70 differs from the filming removal unit 7 in FIG. 3A only in the shape of the housing and the positional relationship of the rollers, etc., and thus has the same function as the components in FIG. 3A. In principle, the elements are denoted by common reference numerals to simplify the description.

The housing 79 ′ is basically substantially the same shape as the housing 79 of the photosensitive unit 11K, and as shown in FIG. 7B, the printer 100 using guide rails 104 and 105 for mounting the photosensitive unit 11K. It is configured to be attachable to the main body.
The non-woven fabric 72 drawn out from the non-woven fabric supply roller 71 is wound around the liquid immersion roller 73, contacts with the liquid supply pad 77 immersed in the liquid reservoir 76, is impregnated with ethanol, and passes through the application roller 74. And is wound up by the nonwoven fabric winding roller 75.

The position of the axial center of the nonwoven fabric winding roller 75 with respect to the housing 79 'coincides with the axial center of the photosensitive drum 111K of the housing 79 in the photosensitive unit 11K. A power transmission coupling member 752 having the same shape as the coupling member 111Ka of the body unit 11K is attached (FIG. 7B).
Therefore, when the filming removal unit 70 is attached to the printer 100, the power transmission coupling 752 is attached to the drive shaft 117Ka of the drive motor 117K (FIG. 2B) for driving the photoconductor unit 11K in the printer 100 body. It is connected to the attached coupling member 117Kb and rotated.

However, the winding speed of the non-woven fabric 72 is set as slow as about 0.1 mm / sec in order to suppress the wear of the non-woven fabric 72, and therefore the rotation speed of the motor 117K serving as the driving source for the photosensitive drum is also correspondingly adjusted. It is controlled by the control unit 5 to decelerate.
Of course, without reducing the rotational speed of the drive motor 117K, the speed is reduced by interposing a reduction mechanism using a gear or the like in the middle of the power transmission path from the coupling member 752 to the rotary shaft of the nonwoven fabric winding roller 75. Any configuration may be used.

In this way, a unit that is not standard equipment of the printer 100 such as a filming removal unit can be replaced with an existing unit (photoreceptor unit 11K in this example), and the mounting unit of the existing unit can be shared. Hereinafter, it is referred to as “mounting compatibility”.
Thus, since the filming removal unit 70 is mounted as in the first embodiment, it is not necessary to provide an installation space in the printer 100, so that the apparatus can be made compact and the filming as in the first embodiment. A dedicated drive source for driving the removal unit 7 is also unnecessary, and the cost can be further reduced.

<Comparison of effects of filming removal processing with other configuration examples>
Hereinafter, the result of a comparative experiment regarding the effect of the filming removal process including the above-described embodiment will be described while describing another configuration example (modification) of the printer according to the present invention.
A. First, eleven types of configuration examples (Configuration 1 to Configuration 11) of the image forming apparatus used in the comparative experiment and configurations of main parts of the comparative example will be described.

(1) Configuration 1
FIG. 8A is a schematic diagram of a main part of the printer according to Configuration 1. FIG.
In the same figure, the image forming units 10Y to 10K show only the photosensitive drums 111Y to 111K (the same applies to other configuration examples).
This configuration 1 is different in that a filming removal unit 710 having a blade 711 is detachable instead of the liquid filming removal unit 7 in the first embodiment described with reference to FIG.

As the blade 711, a metal blade made of SUS is used, and a metal roller 712 having a diameter of 18 mm is provided on the back surface of the intermediate transfer belt 25 as an opposing member of the blade 711 by a biasing mechanism using an elastic member such as a spring (not shown). It is configured to press-contact in the direction 711.
The urging force at this time is large enough to remove the filming material on the surface of the intermediate transfer belt 25 (in this example, the line pressure of the blade 711 against the intermediate transfer belt 25 is 20 N / m). The pressure is set so as to be pressed against the surface of the intermediate transfer belt 25. Although the resilience is strong, since the filming removal process is used only for a short time, the durability of the intermediate transfer belt 25 is hardly affected.
(2) Configuration 2
FIG. 8B is a schematic diagram of a main part of the printer according to Configuration 2.

This configuration 2 is different in that a roller-type filming removal unit 720 having a metal roller 721 is detachable instead of the blade-type filming removal unit 710 in the configuration 1 of FIG.
The metal roller 721 is made of SUS and has a roller diameter of 18 mm. The peripheral surface is roughened by alumite treatment so that the surface roughness Rz is within 0.5 μm to 10 μm (this book) In the example, Rz = 2 μm was used.) In addition, the rough surface processing may be a method such as sandblasting.

A urethane roller 723 having a diameter of 18 mm was pressed against the back surface of the intermediate transfer belt 25 as an opposing member by an urging mechanism using an elastic member such as a spring (not shown). The metal roller 721 and the urethane roller 723 are arranged so that the axes thereof are parallel to each other, and a plane including these two axes is almost orthogonal to the running surface of the intermediate transfer belt 25.
The urging force applied to the urethane roller 723 by the urging mechanism was set so that the pressing amount of the metal roller 721 against the intermediate transfer belt 25 was 0.2 mm.

This filming removal unit 720 is similar to the filming removal unit 7 (FIG. 3B), and when attached to the printer 100, a coupling member (not shown) attached to the drive shaft of the metal roller 721 is used. And is connected to a drive source on the main body side via the power transmission.
During the filming removal process, the circumferential speed ratio θ (the traveling speed of the intermediate transfer belt 25 / the circumferential speed of the metal roller 721) is “1” in the counter direction with respect to the circumferential direction of the intermediate transfer belt 25. Driven by rotation.

Since the peripheral surface of the metal roller 721 is rough, the filming material on the surface of the intermediate transfer belt 25 can be effectively scraped off and removed.
The filming material scraped off from the intermediate transfer belt 25 and adhered to the peripheral surface of the metal roller 721 is scraped off by a rubber blade 722 and collected in a collection box (not shown) in the housing of the filming removal unit 720. Is done.

Also in this case, since the filming removal unit 720 is mounted only for a short time of the filming removal process, the durability of the intermediate transfer belt 25 is hardly affected.
(3) The configuration 3 shown in FIG. 9A is the same as that of the first embodiment, but the liquid type experimental filming removal unit 7 is simplified so that the features of the configuration can be easily understood. (It shows that the nonwoven fabric is impregnated with liquid for filming removal by giving the nonwoven fabric a thickness and hatching. Hereinafter, the filming removal unit in other configuration examples is simplified. Same for display.)

(4) FIG. 9B shows a roll cloth type liquid removal unit 730 attached to and detached from the filming removal unit 7 along the traveling direction of the intermediate transfer belt 25 in the configuration 3 of FIG. 9A. The liquid filming removing unit 7 is arranged so as to be able to remove the liquid adhering to the surface of the intermediate transfer belt 25 with a cloth.
FIG. 14 is a schematic cross-sectional view showing a configuration example of the liquid removal unit 730.

  A nonwoven fabric 732 drawn from a nonwoven fabric roll 731 wound with a nonwoven fabric excellent in water absorption made of a material such as rayon is wound around a roller 733 on the way, and the nonwoven fabric 732 is transferred to the intermediate transfer belt 25 by a winding roller 734. It is wound up so as to move at a predetermined speed in the counter direction with respect to the traveling of the vehicle. The winding speed of the nonwoven fabric 732 by the winding roller 734 is set to be approximately the same as the winding speed of the filming removal unit 7, but when the water absorption of the nonwoven fabric 732 is high, the winding speed of the filming removal unit 7 is It may be slower than the taking speed.

A coupling member (not shown) similar to that of the filming removal unit 7 is also attached to the back end of the rotating shaft of the winding roller 734. When the coupling member is attached to the printer main body, It is connected to a coupling member attached to the drive shaft, and power is supplied.
At a position facing the roller 733 across the intermediate transfer belt 25, for example, a urethane roller is disposed as a counter roller 736, and the intermediate transfer from the back surface is performed so that the contact pressure between the nonwoven fabric 732 and the intermediate transfer belt 25 becomes a predetermined value or more. The belt 25 is supported.

  While the filming removal processing sequence is being executed as described above, the printing operation is not executed, but when the filming substance is wiped off by the filming removal unit 7, a liquid such as ethanol adheres to the intermediate transfer belt 25, If this adheres to the surface of the photoconductive drums 111Y to 111K, the ethanol adhering to the photoconductive drums 111Y to 111K may not completely evaporate when a printing operation is performed immediately after that, and the photoconductive drums 111Y to 111Y. Since there is a possibility of affecting the charging characteristics of 111K, the occurrence of the harmful effect is prevented in advance by wiping off ethanol with the liquid removing unit 730. Further, since the filming substance remaining on the intermediate transfer belt 25 is wiped off even when wiping off ethanol, the filming removal efficiency is further improved.

(5) Configuration 5
FIG. 10A is a schematic diagram of the main part of the printer according to Configuration 5. FIG.
As shown in the figure, in this configuration 5, the belt cleaner 6 is configured to be detachable from the main body of the printer 100, and a roller type filming removal unit 720 can be mounted instead of the belt cleaner 6. .

Therefore, although not shown in particular, the belt cleaner 6 is unitized and provided with a mounting portion (a mounting guide rail or a driving motor) that can be attached and detached.
The housing of the filming removal unit 720 has a shape that can be mounted using the guide rail, and receives a driving force from a driving source common to the belt cleaner 6 through a coupling (not shown) when mounted. It is configured and has mounting compatibility with the belt cleaner 6.

In the case of this example, the opposing roller 61 in the belt cleaner 6 has the same configuration as the opposing roller 723 in the configuration 2 in FIG. 8B, and, like the opposing roller 723, an intermediate transfer belt by an urging mechanism (not shown). It is urged toward 25.
(6) Configuration 6
FIG. 10B is a schematic view of the main part of the printer according to Configuration 6.

As shown in the figure, the configuration 6 is characterized in that the belt cleaner 6 is configured to be detachable from the main body of the printer 100, and a liquid filming removal unit 7 can be mounted instead of the belt cleaner 6. .
Also in this configuration example, when the coupling (not shown) attached to the back end of the drive shaft of the nonwoven fabric winding roller of the filming removal unit 7 is attached to the printer 100, For example, if it is configured to be connected to a coupling attached to the drive shaft of the drive source of the printer main body provided for driving the rotation shaft of the brush roller 62 so as to have mounting compatibility, a separate fill is required. Since it is not necessary to provide a drive source dedicated to the ming removal unit 7, this contributes to cost reduction.

(7) Configuration 7
The printer according to the configuration 7 shown in FIG. 11A is the same as the configuration of the above-described second embodiment, and the configuration of the filming removal unit 70 so that the characteristic part of the configuration in this example can be easily understood. Is shown in a simplified manner.
In this example, the filming substance removing unit 70 is exchanged with the photoconductor unit 11K, but any one of the other photoconductor units 11Y to 11C is exchanged with the filming substance removing unit 70. It doesn't matter.

(8) Configuration 8
FIG. 11B is a schematic diagram illustrating a main part of the printer according to Configuration 8.
In this configuration example, the photosensitive drums 111Y to 111C in the configuration 7 described above are formed by inclining a portion (upstream side) of the intermediate transfer belt 25 above the support roller 27 in the left direction in the drawing during the filming removal process. The transfer surface of the intermediate transfer belt 25 is configured to be separated from the transfer surface.

  When printing a black monochrome image, it is reasonable to stop the wear of the photosensitive drums 111Y to 111C other than the photosensitive drum 111K by stopping them and separating them from the intermediate transfer belt 25. Therefore, in this configuration example, in a printer having such a belt separation mechanism, a filming removal unit 70 is mounted instead of the black photoconductor unit 11K, and the belt separation mechanism is formed during monochrome image formation. It is also used during the removal process.

As a result, even if the liquid used in the filming removal unit 70 adheres to the transfer surface of the intermediate transfer belt 25, it does not adhere to the photosensitive drums 111Y to 111C, so that the image quality is hardly deteriorated.
FIGS. 16A and 16B are diagrams illustrating a configuration example of the belt separation mechanism 200, in which the photosensitive unit 11K is mounted in order to form a monochrome image.

As shown in both drawings, the belt separation mechanism 200 includes a pair of long support frames 201 that rotatably support the roller 23 and the primary transfer rollers 14Y to 14C provided to stretch the intermediate transfer belt 25. It is composed of a pair of cam mechanisms for swinging the same (in the drawing, only the relationship between the support frame on the back side and the cam mechanism is shown for convenience).
The cam mechanism has a cam plate 202 attached to a drive shaft 203 of a drive source (not shown), and the cam plate 202 rotates with the rotation of the drive shaft 203.

  The support frame 201 is pivotally supported by the rotation shaft of the support roller 27 so as to be swingable with respect to the main frame 103 (FIG. 2B) of the main body, and swings in the direction of arrow B in the figure by the tension spring 204. It is so energized. The support frame 201 has an L-shaped cross section, and the peripheral surface of the cam plate 202 is in contact with a tip portion of a portion bent in a direction perpendicular to the paper surface (a hatched portion in the drawing).

When the cam plate 202 is rotated by a drive source (not shown), the support frame 201 is tilted from the state of FIG. 16A in the direction of arrow C as shown in FIG.
At this time, since the support roller 27 exists between the photosensitive drum 111K and the photosensitive drum 111C and supports the back surface of the intermediate transfer belt 25, the support frame 201 swings in the direction of arrow C. Also, the contact state between the photosensitive drum 111K and the transfer surface of the intermediate transfer belt 25 is maintained, and the transfer surface of the intermediate transfer belt 25 is separated from the photosensitive drums 111Y to 111C.

  The roller 24 is a spring that is movable toward a certain direction (in the figure, the horizontal direction A, but not limited to this) outside the orbit of the intermediate transfer belt 25 by an unillustrated urging mechanism. Even when the intermediate transfer belt 25 is in the state as shown in FIG. 16B, the intermediate transfer belt 25 is maintained at a certain level of tension, and the intermediate transfer belt 25 is biased in the direction. 25 is not loosened.

Further, on the downstream side of the belt cleaner 6, a support roller 28 is in contact with and supported by the transfer surface of the intermediate transfer belt 25, and the intermediate transfer belt even if the roller 24 moves in the direction of the arrow A during separation. The positional relationship between the transfer surface 25 and the belt cleaner 6 is not changed.
The belt separation mechanism 200 shown in FIG. 16 is merely an example, and other configurations may be used. For example, other actuators such as a solenoid and a screw feed mechanism may be employed instead of the cam mechanism. Further, instead of moving the intermediate transfer belt 25, a mechanism may be provided in which the photosensitive drums 111Y to 111C are retracted and separated from the intermediate transfer belt 25 integrally or individually.

  Note that the filming removal processing sequence in this configuration example is also basically the same as the flowchart shown in FIG. 5, but “separation of the photosensitive drums 111Y to 111C” is added in the processing of step S104. In addition, when individual drive sources are provided for the photosensitive drums 111Y to 111K, only the drive source corresponding to the photosensitive drum 111K is turned ON.

(9) Configuration 9
FIG. 12A is a schematic diagram of a main part of the printer according to Configuration 9.
This embodiment is characterized in that a filming removal unit 70 is attached instead of the photoreceptor unit 11C, and a blade-type liquid removal unit 740 is attached instead of the downstream photoreceptor unit 11K.

  The liquid removing unit 740 presses the rubber blade 741 against the surface of the intermediate transfer belt 25 at the position where the back surface is supported by the primary transfer roller 14K, scrapes off the liquid at the tip, and puts it in the liquid reservoir 742 inside. to recover. The recovered liquid is discarded when the liquid removal unit 740 is removed. It should be noted that the pressure contact force of the blade 741 on the surface of the intermediate transfer belt 25 in this example is an extent necessary for recovering the liquid and does not need to be so large.

(10) Configuration 10
FIG. 12B is a schematic diagram of a main part of the printer according to the configuration 10.
As shown in the figure, the printer according to the configuration 10 has the cloth type described in the configuration 4 (FIG. 9B) instead of the blade-type liquid removal unit 740 in the configuration 9 in FIG. The difference is that a liquid removal unit 750 having the same configuration as that of the liquid removal unit 730 is mounted. The configuration in which the drive source of the photoreceptor unit 11K can be used as the drive source of the nonwoven fabric winding roller of the liquid removing unit 750 after the mounting to the printer main body is the same as the other examples and has mounting compatibility.

(11) Configuration 11
FIG. 13A is a schematic diagram illustrating a main part of the printer according to the eleventh configuration.
As shown in the figure, in this configuration 11, the liquid filming removal unit 70 is divided into a first unit 760 and a second unit 770, and each of the photoconductor units 11K, 11C and I try to replace it.

FIG. 15 is a schematic cross-sectional view showing a configuration example of the first and second units 760 and 770.
As shown in the figure, the first unit 760 includes a nonwoven fabric supply roller 761, a liquid impregnation roller 763, a first application roller 764, a liquid reservoir 766, a liquid supply pad 767, and the like. Ethanol (not shown) in the reservoir 766 is impregnated and sent out toward the second unit 770.

The second unit 770 is configured so that the nonwoven fabric 762 sent from the first unit 760 is wound around the second application roller 771 and then wound around the nonwoven fabric winding side roller 772.
With this configuration, the nonwoven fabric 762 can contact the intermediate transfer belt 25 at a long distance from the first application roller 764 to the second application roller 771, so that the filming can be performed more efficiently. A removal process can be performed.

  The housings 769 and 735 of the first unit 760 and the second unit 770 are configured to be mountable on the printer body using the mounting rails of the photoreceptor units 11K and 11C, and The driving source of the nonwoven fabric winding side roller 772 of the second unit 770 is configured to be able to use the driving source of the photosensitive unit 11C at the time of mounting, and has mounting compatibility with the photosensitive units 11K and 11C, respectively.

(12) Comparative example (conventional configuration)
FIG. 13B is a schematic diagram illustrating a main part of a printer according to a conventional configuration for comparison with experimental results in Examples using the configurations 1 to 11 described above.
As shown in the figure, in this conventional configuration, no special unit is provided for filming removal processing.

B. Experimental Results Next, the results of filming removal efficiency evaluation experiments performed on Examples 1 to 12 and Comparative Examples based on the above configurations 1 to 11 will be described. Here, the reason why the number of embodiments is one more than the number of configuration examples is that even in the same configuration example, there are different embodiments by changing the type of liquid for filming removal ( Examples 3 and 4).

In this evaluation experiment, Konica Minolta Co., Ltd. color printer (bizhub C754: system speed 310mm / sec. “Bizhub” is a registered trademark of the company) was modified to produce experimental machines according to each example. did.
FIG. 17 is a list showing the experimental results.
In the table, in the column of “removable member configuration”, the numbers of the above-described configuration examples corresponding to Examples 1 to 12 are described. For embodiments using a liquid film removal unit, the type of wiping liquid used is listed in parentheses along with its component number. For example, as Example 3, “Configuration 3 (water)” is described as “wiping liquid used for the filming removal unit 7” in the printer according to Configuration 3 shown in FIG. 9B. It means that it was used.

In the experiment of each embodiment, in order to generate a filming state on the transfer surface of the intermediate transfer belt 25, the operation of forming a solid image with a coverage of 5% for each development color on an A3 size longitudinal recording sheet is repeated 10,000 sheets. It was.
The evaluation items in the experiment cover five items of “filming removal”, “removal speed”, “additional cost”, “soil in the next process”, and “overall evaluation”.

(1) Filming removal “Filming removal” evaluated whether or not the filming substance finally attached to the intermediate transfer belt could be completely removed by experiments.
Those that could be completely removed were marked with “◯”, and those that could not be completely removed were marked with “x”.

Note that whether or not the filming material on the intermediate transfer belt 25 was completely removed was determined by visual evaluation after the experiment.
(2) Removal speed The “removal speed” indicates the speed at which the filming substance can be completely removed, and was evaluated as follows using the rotation of the intermediate transfer belt as a parameter. The smaller the number of rotations of the intermediate transfer belt until the filming material is completely removed, the better the removal speed.
○ 3: Filming material was completely removed by less than 5 revolutions.
○ 2: The filming substance can be completely removed by a rotation of 5 rotations or more and less than 10 rotations.
○: The filming substance could not be completely removed unless it was rotated 10 times or more.

(3) Additional cost “Additional cost” indicates an increased manufacturing cost compared to the configuration of Comparative Example 1 in which no filming removal unit is used.
○: No additional cost was generated.
○ △: An additional cost of less than $ 10 (US dollars) occurred.
Δ: An additional cost of 10 dollars (US dollars) or more occurred.

(4) Contamination of the next process member “Contamination of the next process member” is executed first after the filming removal process is completed and the filming removal unit is removed so that the normal printing operation can be performed. The result of having confirmed visually the presence or absence of the stain | pollution | contamination of the image on the recording sheet output by the printing operation is shown.
○: No contamination occurred.
(Triangle | delta): Although slight dirt generate | occur | produced, it was a thing of the grade which does not affect an image.

(5) Comprehensive evaluation Among each evaluation of said (1)-(4), what had "x" at least was evaluated as "*", and others evaluated as "(circle)".
<Evaluation>
Hereinafter, the results of this evaluation experiment will be described with reference to the table of FIG.

(1) About filming removal About all of Examples 1-12 which applied this invention, the filming substance was able to be removed completely.
In Comparative Example 1, it was impossible to completely remove the filming substance.
(2) About removal speed The removal speed of generation | occurrence | production of filming improves by using a liquid filming removal unit (Examples 3-5, 7-11).

In particular, when the liquid removal unit is provided downstream of the liquid filming removal unit (Examples 5, 10, and 11), and when the contact area between the liquid-impregnated nonwoven fabric and the intermediate transfer belt is increased ( In Example 12), it is evaluated as “◯ 3”, and it can be seen that the removal efficiency is excellent.
(3) Additional cost When the apparatus of Comparative Example 1 (conventional configuration) is used as a reference, it does not have mounting compatibility with the belt cleaner 6 or the photoreceptor units 11Y to 11K, and a separate mounting portion for the filming removal unit. For the first to fifth embodiments that need to be provided, additional costs are incurred due to newly installed guide rails and drive units. In particular, in the fifth embodiment (configuration 4 in FIG. 9B), it is necessary to separately provide two unit mounting portions, ie, the filming removal unit 7 and the liquid removal unit 730. Is the biggest.

  However, even if the additional cost is determined to be “Δ” as in the fifth embodiment, the serviceman brings the filming removal unit and the liquid removal unit at the time of maintenance. Needless to say, the initial price can be significantly reduced compared to the case where these units are standard printers from the beginning.

  Compared to this, in the configurations of Examples 6 to 12 that are installed in place of the existing belt cleaner 6 and the photoreceptor units 11Y to 11K, the additional cost for providing a separate mechanism for attaching a filming removal unit or the like is This is unnecessary, and not only has a great merit in cost, but also eliminates a useless space for mounting the filming removal unit and the like, and the apparatus can be made compact.

(4) Contamination in the next step When the liquid removal unit is provided on the downstream side of the liquid filming removal unit (Examples 5, 10, and 11) and during the filming removal process by the liquid filming removal unit When the other photosensitive drum was separated from the intermediate transfer belt (Example 9), the contamination in the next process could not be confirmed, and was evaluated as “◯”. In other examples, it was only a slight stain and was evaluated as “Δ”.

(5) Comprehensive evaluation As a result of the above evaluation experiment, “◯” was obtained as the comprehensive evaluation in all Examples 1 to 12 according to the present invention.
Among them, Examples 10 and 11 (Configurations 9 and 10 in FIGS. 12A and 12B) were excellent in all evaluation items.

<Other variations>
As described above, the present invention is not limited to the above-described embodiments and configuration examples, and the following modifications can be considered.
(1) In the above embodiment, the liquid filming removal unit is configured to wind up the nonwoven fabric while impregnating the liquid with the liquid. However, for example, the first and second outer layers are made of a foamable material. The rollers are arranged in parallel with their peripheral surfaces in contact with each other, and the second roller is connected to the first roller while rotating in the counter direction while the peripheral surface of the first roller is in contact with the intermediate transfer belt. It is good also as a structure which is made to rotate in a counter direction and to immerse a part of 2nd roller in the liquid for filming removal. Thereby, the liquid is supplied to the first roller via the second roller, and the filming substance on the intermediate transfer belt is wiped off by the first roller impregnated with the liquid.

  (2) In the above embodiment and configuration example, only one filming removal unit can be attached to the printer 100 (in the configuration 11 of FIG. 13A, one filming removal unit is divided). Therefore, the number of mounting portions is further increased along the traveling path of the intermediate transfer belt 25 so that two or more filming removal units of the same type or different may be mounted. By doing so, the effect of filming removal can be further increased. In addition, when the liquid removal unit is mounted, any position is possible as long as it is downstream from the mounting position of the filming removal unit and upstream from the primary transfer position of the uppermost photosensitive drum. A mounting part may be provided.

Of course, even in these cases, the construction of the photoconductor units 11Y to 11K and the belt cleaner 6 so as to be detachable and compatible with a plurality of units can minimize the generation of additional costs. Needless to say, the printer 100 can be made compact.
(3) In the configuration 8 (FIG. 11B), since the intermediate transfer belt 25 is retracted from the photosensitive drums 111Y to 111C during monochrome printing, the photosensitive unit 11K and the filming removal unit 70 are used. I exchanged it with.

  However, if the photosensitive drums 111Y to 111K are originally separated from the intermediate transfer belt 25 during monochrome printing, the photosensitive unit to be replaced is not limited to the photosensitive unit 11K. In addition, even when a plurality of filming removal units or a filming removal unit and a liquid removal unit are mounted instead of the plurality of photosensitive units, the photosensitive drums of other non-replaceable photosensitive units are used as intermediate transfer belts. Can be separated from

  (4) In the above embodiment, as an example of the liquid removal unit, an example using a non-woven fabric (see FIG. 14) and an example using a blade (such as the liquid removal unit 740 in the configuration 9 in FIG. 12A) are described. However, it may be a simple configuration in which a pad made of a material having an excellent liquid water retention capability is pressed. This is because one filming removal process is completed in a relatively short time, and therefore, it is not necessary to replenish liquid as long as the pad has a certain amount of water retention. In this case, if the pad itself can be replaced, it is convenient and convenient for maintenance.

  (5) In the above embodiment, when the service person periodically checks or when the user notices the deterioration of the image quality and calls the service person, as a part of the maintenance, the service person removes the filming removal unit or the liquid. It was assumed that a film removal process was performed by bringing a removal unit. Thus, as described above, there is an advantage that the product cost can be reduced as compared with the case where the filming removal unit or the like is provided as a standard in the printer.

  However, in addition to this, for example, in a company or a large office, there are not a few cases where multiple printers of the same model are deployed. In such a case, a filming removal unit or the like is optional. If you purchase only one printer, you can use it for multiple printers. Even in such a usage pattern, it is possible to reduce the cost per printer.

  In addition, if there is only one printer and the user purchases a filming removal unit or the like, the filming removal unit can be used only when the filming removal process is necessary, even if there is little cost advantage. Therefore, there are advantages that the intermediate transfer belt can be deteriorated as in the prior art, and that the trouble of having to constantly replenish the filming removal liquid is eliminated.

  (6) In the above embodiment, an instruction for filming removal processing is received from a serviceman or the like via the operation panel 8 or a dedicated switch (see step S101 in FIG. 5). When the unit detection unit 7b (FIG. 3B) detects that the filming removal unit 7 is mounted, it is considered that there has been an instruction for filming removal processing, and then the maintenance door is closed. A filming removal process may be automatically performed when detected by a door opening / closing detection switch. This is because the intention to instruct execution of the filming removal process can be inferred from the act of attaching the filming removal unit 7 itself.

(7) The control unit 5 may automatically determine the timing of the filming removal process and notify the user or the like.
For example, when the value indicating the degree of filming is equal to or greater than a preset threshold value, it is determined that filming processing is necessary, and a message to that effect is displayed or a warning is given. Warning means for warning the user such as making a sound or turning on a lamp may be provided.

  In this case, the control unit 5 counts the cumulative number of prints from the previous filming removal process and the travel distance of the intermediate transfer belt or the photosensitive drum from the previous filming removal process as the index value. Then, it may be stored in the EEPROM 55, and it may be determined that the filming removal process is necessary when the value reaches a threshold that is considered to require the filming removal process by an experiment or the like in advance.

Alternatively, the generation of filming material can be determined by the controller 5 by monitoring the surface state of the intermediate transfer belt 25 using an appropriate sensor.
For example, a plurality of reflective photoelectric sensors are arranged at predetermined intervals in the width direction of the intermediate transfer belt 25 to detect reflected light from the intermediate transfer belt 25. Normally, if filming occurs, the portion becomes whitish. Therefore, if the ground color of the transfer surface of the intermediate transfer belt 25 is set to a color with low brightness, the control unit 5 outputs the output of the reflective photoelectric sensor. Whether or not filming has occurred can be determined by monitoring the above.

  (8) In the above embodiment, filming removal of the intermediate transfer belt has been described. However, in a printer that uses an intermediate transfer drum as an image carrier rotating body, the intermediate transfer drum is a target for filming removal. Further, in a model that uses a photosensitive belt instead of the photosensitive drum, it may be applicable to filming removal processing of the photosensitive belt.

(9) In the above embodiment, a tandem color printer is used as the image forming apparatus. However, the scope of the present invention may be a monochrome printer, a copying machine or a facsimile machine. However, the present invention is applicable to general image forming apparatuses having an image bearing rotating body that may generate a filming substance.
Further, the contents of the above-described embodiment and modification examples may be combined as much as possible.

  The present invention is suitable as a technique for removing filming substances on the surface of an image bearing rotating body such as an intermediate transfer belt in an image forming apparatus.

DESCRIPTION OF SYMBOLS 1 Image process part 2 Intermediate transfer part 25 Intermediate transfer belt 3 Paper feed part 4 Fixing part 5 Control part 6 Belt cleaner (toner cleaning unit)
6c Belt cleaner drive unit 7, 70, 710, 720, 760, 770
Filming removal unit 730, 740, 750
Liquid removal unit 7a Filming removal unit drive unit 7b Filming removal unit detection unit 71 Non-woven fabric supply roller 72 Non-woven fabric (cloth belt)
73 Liquid impregnation roller 74 Application roller 75 Non-woven fabric winding roller 76, 766 Liquid reservoir 76a Ethanol 77 Liquid supply pad 78 Spring 79, 79 ', 735, 773, 769 Housing 10Y-10K Image forming unit 11Y-11K Photosensitive Body unit 12Y to 12K exposure unit 13Y to 13K development unit 111Y to 111K photosensitive drum 111Ka, 117Kb, 751
Coupling member (power transmission means)
117K Drive motor 101, 102, 104, 105 Guide rail 103 Main frame 170 Filming removal unit mounting part 200 Belt separation mechanism

Claims (18)

An image forming apparatus for forming a toner image on an image carrying surface of a rotating image carrying rotary body by an image forming unit and transferring the toner image formed on the image carrying surface onto a recording sheet. ,
At least one mounting portion to which a filming removal unit for removing the filming substance attached to the image bearing surface of the image bearing rotor is detachable;
When a filming removal unit is mounted on the mounting portion, the image carrier rotating body circulates in a state where there is no toner image forming operation by the image forming unit, and the filming removal operation is performed by the filming removal unit. And an image forming apparatus. The image forming means includes a photosensitive unit having a photosensitive rotator,
Among the image forming means, at least the photosensitive unit is configured to be detachable from the apparatus main body, and the filming removal unit is configured to be mounted instead of at least the photosensitive unit, The image forming apparatus according to claim 1, wherein at least a mounting portion on which the photosensitive unit is mounted is shared as a mounting portion on which the filming removal unit is mounted. The filming removal unit includes:
A rotating body that rotates by receiving a driving force from the apparatus main body, and is the same drive as a driving source that drives the photosensitive rotating body of the photosensitive unit when mounted on the apparatus main body instead of at least the photosensitive unit The image forming apparatus according to claim 2, further comprising a power transmission unit that is coupled to a driving shaft of a source and transmits the driving force to the rotating body. A toner cleaning unit for cleaning residual toner on the image bearing surface of the image bearing rotating body is detachable from the apparatus main body, and the filming removal unit is configured to be mounted in place of the toner cleaning unit. The image forming apparatus according to claim 1, wherein a mounting portion on which the toner cleaning unit is mounted is shared as a mounting portion on which the filming removal unit is mounted. The toner cleaning unit and the filming removal unit each have a rotating body that rotates by receiving a driving force from the apparatus main body,
The filming removal unit is connected to a drive shaft of the same drive source as the drive source for driving the toner cleaning unit and receives a driving force when mounted on the apparatus main body instead of the toner cleaning unit. The image forming apparatus according to claim 4, further comprising: means. The filming removal unit includes:
6. The filming material is removed by sliding a filming removing member impregnated with a liquid for removing filming on the image bearing surface. The image forming apparatus according to any one of the above. The image is removed by the filming removal unit between the position where the filming removal unit is mounted and the position downstream of the image carrying surface in the running direction and the position where the photosensitive rotating body of the photosensitive unit is in contact. The image forming apparatus according to claim 6, wherein a mounting portion to which a liquid removing unit for removing the liquid adhering to the carrying surface can be mounted is provided separately. The liquid removal unit is
8. The image forming apparatus according to claim 7, wherein a liquid absorbing member is brought into contact with the image carrying surface of the image carrying rotating body to absorb and remove the liquid adhering to the image carrying surface. . The liquid absorbing member is a cloth belt,
The configuration is such that the cloth belt is brought into contact with the image carrying surface while the cloth belt is moved while the cloth belt wound in a roll is wound by another roller. The image forming apparatus described in 1. The liquid removal unit is
8. The structure of scraping off and removing the liquid adhering to the image carrying surface by bringing the tip of the blade into contact with the image carrying surface of the image carrying rotating body. Image forming apparatus. The filming removal unit includes:
With the roller having a roughened peripheral surface in contact with the image carrying surface of the image carrying rotating body, the filming material is removed by rotating the image carrying surface in the running direction and the counter direction. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The filming removal unit includes:
5. The image forming apparatus according to claim 1, wherein the image bearing surface of the image bearing rotating body is pressed with a predetermined pressing force to scrape the filming substance. apparatus. The filming removal unit includes:
A first unit having an impregnation part for impregnating the filming removal member with a predetermined liquid when the cloth-like filming removal member wound in a roll shape is pulled out; and the cloth-like from the first unit And a second unit including a winding unit that winds up the filming removing member.
The filming removing member is configured to remove the filming material by rubbing against the image carrying surface during the period from the first unit to the second unit. Item 6. The image forming apparatus according to any one of Items 1 to 5. The mounting portions for mounting the filming removal unit are provided at a plurality of locations along the circular trajectory of the image bearing surface of the image bearing rotating body. The image forming apparatus according to claim 1, wherein the image forming apparatus can be attached to each attachment portion. The image forming means includes a plurality of photoconductor units that form toner images of a plurality of colors, and at least one photoconductor unit is replaceable with a filming removal unit. The image forming apparatus according to any one of the above. The image forming means includes a plurality of photoconductor units that form toner images of a plurality of colors, and includes other photoconductor units excluding the photoconductor unit on the most downstream side in the running direction of the image carrying surface of the image carrying rotor. At least one photoconductor unit is replaceable with the filming removal unit, and at least one photoconductor unit on the downstream side in the running direction of the image bearing surface with respect to the photoconductor unit exchanged with the filming removal unit is The image forming apparatus according to claim 7, wherein the image forming apparatus is replaceable with a liquid removal unit. And a separation unit configured to relatively separate the photosensitive rotator of the photosensitive unit that has not been replaced with another unit from the image carrying surface of the image carrying rotator during execution of the filming removal operation. The image forming apparatus according to claim 15 or 16. The image forming apparatus according to claim 17, wherein among the plurality of photosensitive units, the photosensitive unit replaced with another unit includes a photosensitive unit that forms a black toner image.

Images