JP3861960B2 - Cleaner and image forming apparatus using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cleaner that realizes a cleaning process such as an electrophotographic method, and more particularly to an image forming apparatus that transfers an image formed by a plurality of image forming units directly onto a recording carrier or via a recording material. The present invention relates to a cleaner that cleans a recording and conveying body and an image forming apparatus using the cleaner.
[0002]
[Prior art]
A conventional tandem type image forming apparatus has, for example, a plurality of image forming units (for example, employing an electrophotographic system) on which toner images of yellow, magenta, cyan, and black color components are formed. For example, a conveyance belt that is circulated and conveyed across a pair of stretching rolls is disposed at a portion that performs the transfer, and a transfer device such as a corotron is disposed on the back surface of the conveyance belt that faces the image forming unit. A recording material (paper, OHP sheet or the like) is adsorbed and held on the recording material, and a toner image formed by an image forming unit is transferred to the recording material (for example, Japanese Patent Laid-Open No. Hei 2-163777). reference).
[0003]
By the way, in the belt conveyance method using this type of conveyance belt, the toner image from the image forming unit is transferred onto the conveyance belt other than the recording material due to the wrong selection of the recording material size or the recording material jam processing. In the process control (image density control), the toner patch for each color is transferred onto the conveyor belt and the density is read by a sensor or the like to control the image density or registration. In the control (hereinafter referred to as registration control), the ladder pattern of each color is transferred onto the conveyance belt, the pitch of the ladder pattern is read with a sensor or the like, and the position of each color toner image is adjusted positively on the conveyance belt. Some toner images are transferred.
[0004]
In such a type, if the toner image transferred on the conveying belt is left as it is, it causes the back surface of the next recording material to be stained. In order to clean the toner image, a belt cleaner using a blade or a brush is provided.
The belt cleaner is temporarily separated from the conveyance belt during the recording material conveyance by the conveyance belt, in other words, during the image forming operation by the image forming unit, so that the rotation operation of the conveyance belt is not hindered. There has already been proposed a technique for performing a cleaning cycle in contact with a belt (see, for example, Japanese Patent Application Laid-Open No. 2-163777).
[0005]
[Problems to be solved by the invention]
However, in this type of contact / separation type belt cleaner, since the cleaner is separated at the time of image formation, the background fogging toner that may occur at the time of image formation cannot be removed in a timely manner. If the conveying belt conveys the recording material, the recording material may be stained on the back surface, or if the conveying belt is an intermediate transfer belt, the recording material may be stained on the surface.
Further, since the belt cleaner performs contact / separation operation, there may be a case where the toner remains on the retraction operation of the belt cleaner, and this may cause the back surface contamination or the surface contamination of the recording material. .
[0006]
In order to solve such a technical problem, it is considered to adopt a configuration in which a belt cleaner is always in contact with the conveyor belt, but a cleaning member such as a blade or a brush is always in contact with the conveyor belt. As a result, the conveyor belt and the cleaning member are likely to change with time, resulting in a technical problem that the life of the conveyor belt and the belt cleaner is remarkably shortened.
[0007]
The present invention has been made to solve the above technical problem, and a plurality of image forming units are arranged in parallel, and an image formed by each image forming unit is transferred to the recording carrier side. It is an object of the present invention to provide a cleaner capable of effectively avoiding a stain phenomenon on a recording material, and to sufficiently extend the life of the apparatus, and an image forming apparatus using the same.
[0008]
[Means for Solving the Problems]
  That is, according to the present invention, as shown in FIG. 1, a plurality of image forming units 1 (for example, 1 a to 1 d) are arranged in parallel, and a recording transport body 2 circulated and transported to a portion facing each image forming unit 1. In a cleaner 5 for cleaning the recording / conveying body 2, the recording / conveying body 2 is used to transfer the image formed on the image forming unit 1 directly or via the recording material 3 to the recording / conveying body 2. The cleaning brush 6 is disposed so as to be always in contact with the conveyance body 2, and the cleaning ability adjustment means 7 that adjusts the cleaning ability of the cleaning brush 6 with respect to the recording conveyance body 2.The amount of biting of the cleaning brush 6 into the recording carrier 2 is variably adjusted,In the normal image forming mode for cleaning the transfer residual image after the normal image forming process, and for controlling the image forming process, a control image is formed on the recording carrier 2 and the control image on the recording carrier 2 is directly The cleaning capability is adjusted in the imaging process control mode to be cleaned, and the cleaning capability is set higher than in the normal imaging mode at least in the imaging process control mode so that the control image can be cleaned. To do.
[0009]
In this case, when the cleaner 5 is incorporated in the image forming apparatus, as shown in FIG. 1, a cleaning ability control means for controlling the cleaning ability of the cleaning ability adjusting means 7 in accordance with the dirt state on the recording / conveying member 2. 8 is preferably included.
The present invention is also directed to an image forming apparatus provided with the cleaner 5 described above.
[0010]
In such technical means, the image forming apparatus that is the subject of the present application is a so-called tandem type (including both vertical and horizontal types) in which a plurality of image forming units 1 are arranged in parallel.
In addition, as an image forming method of the image forming unit 1, an electrophotographic method, an electrostatic recording method or the like is used, and an image transfer method to the recording material 2 on the recording material 2 directly or on the recording material 2 is also described. A method of transferring an image formed by the image forming unit 1 to the recording material 3 side via a transfer means 4 (see FIG. 1), such as an electrophotographic method or an electrostatic recording method, is mainly used.
Further, the recording / conveying member 2 is not limited to the one that conveys the recording material 3, and may be an intermediate transfer member that temporarily transfers and holds the respective color component images before being transferred to the recording material 3. The specific form of the recording / conveying body 2 may be either a belt shape or a drum shape. For example, as shown in FIG. 1, in a so-called tandem type in which a plurality of image forming units 1 are arranged in parallel, From the viewpoint of the arrangement of the forming units and the image alignment, the belt-like recording carrier 2 is often used.
[0011]
Further, the layout of the cleaner 5 may be appropriately selected. For example, the belt-like recording / conveying body 2 requires at least a backup member for supporting the recording / conveying body 2, but from the viewpoint of reducing the number of parts. For example, it is preferable to use a tension roll of the belt-like recording / conveying member 2 as a backup member.
[0012]
Further, as long as the cleaning brush 6 can clean the recording / conveying body 2, the recording / conveying body 2 is cleaned by using a brush bias method (mainly using an electric force by applying a bias to the cleaning brush 6. Method), fur brush method (mainly, a method of cleaning the recording and conveying body 2 using a mechanical force by the waist of the cleaning brush 6), and the like.
[0013]
  Furthermore, the cleaning ability adjusting means 7 needs to be adjustable in two or more stages at least in a contact state.
  About the setting of the cleaning capability level at this time, it is preferable to include the original cleaning capability level of the cleaner 5 and a weaker cleaning capability level.
  The cleaning capability adjusting means 7 includes all types that variably adjust the cleaning capability. As a typical mode, I. the amount of biting (contact pressure) of the cleaning brush 6 with respect to the recording carrier 2 II. A mode in which the bias applied to the cleaning brush 6 in the brush bias system is variably adjusted, III. A mode in which the rotation speed of the cleaning brush 6 in the fur brush system is variably adjusted, IV. Aspect etc. are mentionedHowever, in the present invention, at least I. The aspect containing is employ | adopted.
[0014]
The cleaning ability control means 8 controls the cleaning ability of the cleaning ability adjusting means 7 in accordance with the dirt state on the recording / conveying body 2. However, from the viewpoint of simplification of the apparatus configuration, “stained state on the recording carrier 2” and “used in the image forming apparatus during non-image formation”. Each mode ”is associated with each other in advance, and the cleaning ability is controlled according to each mode used in the image forming apparatus, for example, a cleaning cycle, an image forming mode, a process control mode, and a resist control mode. You just have to do it.
[0015]
As a prior art for adjusting the cleaning ability of the cleaner, for example, there is one disclosed in JP-A-6-95527.
However, this prior art is based on the assumption that the cleaning member is in contact with and separated from the transfer material carrier (corresponding to the recording carrier of the present application), and the cleaning ability is adjusted according to each mode used in the image forming apparatus. Therefore, this prior art does not assume any adjustment of the cleaning ability at the time of non-image formation, the point that the cleaning brush always contacts the recording carrier 2, and the cleaning ability adjusting means 7 is provided. There is no description or even suggestion that the cleaning ability is adjusted including during non-image formation.
Therefore, the present invention is completely different from the prior art in terms of technical problems and solutions.
[0016]
Next, the operation of the technical means described above will be described.
In FIG. 1, a cleaning brush 6 that is always in contact with the recording carrier 2 is disposed on the cleaner 5.
The cleaning ability adjusting means 7 adjusts the cleaning ability of the cleaning brush 6 with respect to the recording carrier 2.
For example, the cleaning capability is variably adjusted when a sufficient cleaning capability is required as in a cleaning cycle and when a sufficient cleaning capability is not required as in the image forming mode.
Further, the cleaning ability control means 8 controls the cleaning ability of the cleaning ability adjustment means 7 in accordance with the dirt state on the recording transport body 2.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.
Embodiment 1
FIG. 2 shows Embodiment 1 of a color image forming apparatus to which the present invention is applied.
In the figure, the color image forming apparatus has four image forming units 22 (specifically, 22a to 22d) in a vertical direction in a main body housing 21 (in this embodiment, black, yellow, magenta, and cyan). A recording material supply cassette 23 that accommodates a recording material (not shown) such as paper for supply is disposed below the recording material supply cassette, and a recording material supply cassette is provided at a position corresponding to each image forming unit 22. The recording material conveyance path 24 serving as the recording material conveyance path 23 is arranged in the vertical direction.
[0018]
In the present embodiment, the image forming units 22 (22a to 22d) are for black, yellow, magenta, and cyan in order from the upstream side of the recording material conveyance path 24 (the arrangement is not necessarily in this order). The toner image is formed, and includes a photoconductor cartridge 30 and an exposure unit 40.
Here, the photoconductor cartridge 30 includes, for example, a photoconductor drum 31, a charging roll 32 that precharges the photoconductor drum 31, and a static image formed by exposure on the charged photoconductor drum 31 by the exposure unit 40. A developing device 33 that develops the electrostatic latent image with a corresponding color toner (for example, negative polarity in the present embodiment) and a cleaner 34 that removes residual toner on the photosensitive drum 31 are integrally formed into a cartridge. .
On the other hand, the exposure unit 40 stores a semiconductor laser (not shown), a polygon mirror 42, an imaging lens 43, and a mirror 44 in the case 41, and deflects and scans light from the semiconductor laser (not shown) with the polygon mirror 42. An optical image is guided to an exposure point on the photosensitive drum 31 via the image lens 43 and the mirror 44.
[0019]
Further, in the present embodiment, as shown in FIGS. 2 and 3, a conveyance belt 80 that circulates along the recording material conveyance path 24 is provided at a position corresponding to each photosensitive drum 31 of each image forming unit 22. It is arranged.
The conveying belt 80 is a recording material.(Not shown)It is composed of a belt material that can be electrostatically adsorbed (plastic film such as PET and PVdF, and elastic material such as urethane and urea).⁶-10¹²A high resistance coating layer (not shown) of about Ω · cm is formed.
The conveyor belt 80 is stretched between a pair of stretching rolls 81 and 82 (for example, a metal roll, an elastic body roll, etc.). In this embodiment, the upper stretching roll 82 is a drive roll, The tension roll 81 on the side is a driven roll.
[0020]
Furthermore, a transfer roll 50 (for example, 10 in this example) is provided on the back side of the conveyance belt 80 corresponding to the photosensitive drum 31 of each image forming unit 22.^Three-10^TenΩ · cm), and the recording material on the photosensitive drum 31 and the conveyor belt 80 is transferred by the transfer roll 50.WhenIt comes to stick. A transfer bias power source (not shown) is connected to the transfer roll 50 so that a predetermined transfer bias is applied at an appropriate timing.
[0021]
In the present embodiment, the recording material supply cassette 23 has a recording material.TheA takeaway roll 61 for picking up is provided, and a recording material is provided in the recording material conveyance path 24 located between the takeaway roll 61 and the transfer portion of the most upstream image forming unit 22a.TheA feed roll 62 that is sent out at a predetermined timing is provided. A suction roll 90 is disposed at the entrance portion of the conveyor belt 80.
Further, a fixing device 64 is provided in the recording material conveyance path 24 located on the downstream side of the most downstream image forming unit 22d, and a discharge roll 66 for discharging the recording material is provided on the downstream side of the fixing device 64. The discharged recording material is accommodated in an accommodation tray 67 formed in the upper part of the main body housing 21. In FIG. 2, reference numeral 65 denotes a recording material sent from the conveyor belt 80.TheA recording material guide for guiding the fixing device 64.
[0022]
Furthermore, in the present embodiment, as shown in FIG. 3, a belt cleaner (cleaner) 110 is disposed on the downstream side of the most downstream image forming unit 22 d of the conveyance belt 80 and at a portion facing the stretching roll 82. ing.
As shown in FIGS. 3 and 4, the belt cleaner 110 has a cleaning brush 113 mounted in a cleaner case 112, the cleaning brush 113 is always in contact with the conveyor belt 80, and is driven to rotate by a brush drive motor 116. It is what I did.
In the present embodiment, as the cleaning brush 113, a brush material made of, for example, nylon or polypropylene is used around the rotating shaft.
[0023]
In particular, in the present embodiment, a position changing mechanism 120 that adjusts the amount of the cleaning brush 113 that bites into the conveyor belt 80 is provided.
The position changing mechanism 120 supports the cleaner case 112 so as to be swingable about the swinging fulcrum 111, and is provided with an eccentric cam 121 that is in contact with the positioning wall 114 of the cleaner case 112 so as to be rotatable. In this embodiment, an urging spring 115 for urging the positioning wall 114 toward the eccentric cam 121 is attached.
[0024]
In the present embodiment, the eccentric cam 121 is formed by cutting away a part of the circular cross section. By rotating the eccentric cam 121 by the position variable motor 122, the cleaner case 112 swings, and as a result Therefore, the position of the cleaning brush 113 is variably set in two stages.
Here, as shown in FIGS. 5A and 5B, the two-stage position of the cleaning brush 113 is set to the cleaner position: (1) (corresponding to the weak nip position), and the cleaner position: (2) (to the strong nip position). Equivalent)), and when the cleaning position: (1), the amount of biting of the cleaning brush 113 is N, and when the cleaning position: (2), the amount of biting of the cleaning brush 113 is M, M> N (in this example, For example, N is set to 0.5 mm and M is set to 1.5 mm).
[0025]
Next, the reason why the amount of biting of the cleaning brush 113 is variably set in two stages, M and N, in the present embodiment will be described.
Now, as shown in FIG. 9, a cleaning brush 113 (for example, d = φ24 mm) is disposed at a predetermined bite amount k on the opposing roll 118 (for example, e = φ16 mm), and the cleaning brush 113 is continuously rotated in this state. Prepare an experimental model.
Using this experimental model, the change over time of the brush diameter with respect to the brush operating time when the amount of biting k of the cleaning brush 113 was made constant was examined, and the result shown in FIG. 10 was obtained.
According to FIG. 10, the brush diameter changes (converges) from the initial value φ24 mm to φ23.5 mm when a predetermined time elapses when the brush biting amount k is constant at 0.5 mm, and the brush biting amount k. It was confirmed that the brush diameter changed (converged) from the initial value of φ24 mm to φ22.5 mm after a predetermined time had elapsed when the value of 1.5 mm was constant.
[0026]
Further, when the change in the brush nip width n with respect to the change in the brush diameter when the brush biting amount k was constant (for example, 1.5 mm) was examined using the experimental model shown in FIG. 9, the result shown in FIG. 11 was obtained. .
According to FIG. 11, the nip width n when the brush diameter is initial is about 7.5 mm. However, as shown in FIG. 10 described above, for example, when the brush diameter changes from φ24 mm to φ22.5 mm, the brush nip width n also becomes 7 mm. It is understood that it changes from 5 mm to 5 mm.
Therefore, if the amount of brush bite is large (for example, 1.5 mm), the amount of change in the brush diameter is also large. is there.
[0027]
FIG. 12A shows a cleaning efficiency graph of a solid image patch (Cin 100%) with Toner Coverage 100%, and FIG. 12B shows a cleaning efficiency of a halftone image patch (Cin 10%) with Toner Coverage 10%. The graph of is shown.
According to FIG. 12A, it is understood that the cleaning performance is OK when the brush nip width is about 7 mm.
On the other hand, according to FIG. 12B, it is understood that the cleaning performance is OK when the brush nip width is about 2 mm.
That is, the patch shown in FIG. 12A corresponds to a process control patch for process control, for example. To clean the patch, 7 mm is required for the nip width, and the patch shown in FIG. It corresponds to fogging and it is understood that a nip width of 2 mm is sufficient to clean it.
[0028]
As described above, the degree of change with time of the cleaning brush 113 depends on the amount of biting, and the amount of biting of the cleaning brush 113 can be made variable depending on the use conditions. In the embodiment, the amount of biting of the cleaning brush 113 is set to M and N.
[0029]
Further, FIG. 4 shows a drive control system of the belt cleaner 110 used in the present embodiment.
In the figure, the drive control device 130 is constituted by a microcomputer system comprising, for example, a CPU, a RAM, a ROM, and an I / O port, and the CPU is positioned from a belt drive motor (not shown) of the conveyor belt 80. Capture the signal, execute the drive control program in the ROM (FIGS. 6 to 8 in this example) in accordance with the cleaning cycle, register control (abbreviation of resist control) mode, process control (abbreviation of process control) mode, and print mode, The position variable motor 122 of the position changing mechanism 120 and the brush drive motor 116 of the cleaning brush 113 are driven and controlled.
[0030]
In this embodiment, a resist control mark for registration control (for example, a ladder pattern) and a process control mark for process control are created on the transport belt 80, and the most downstream of the transport belt 80. A mark sensor 140 for detecting a process control mark or a registration control mark is disposed at a position corresponding to the downstream side of the image forming unit 22d and the front side of the stretching roll 82.
[0031]
  Next, the operation of the color image forming apparatus according to the present embodiment will be described.
  In this embodiment,I.Cleaning cycle,II.Cash register mode,III.Pro-con mode,IV.Four basic operations in the print mode are performed.
  In the present embodiment, the belt cleaner 110 is set to the cleaner position: (1) when the conveyance belt 80 is not driven (during non-image formation).
I.Cleaning cycle
  This is a cycle in which the belt cleaner 110 is operated immediately after the image forming apparatus is turned on, after a jam occurs, or every several jobs, in order to remove toner, foreign matter, and the like on the conveyance belt 80. The processing when a jam occurs will be described in the print mode.
  In this case, as shown in FIG. 6, the drive controller 130 sets the belt cleaner 110 to the cleaner position: (2) by the position changing mechanism 120 and then turns on the belt cleaner 110 (rotates the cleaning brush 113). And the belt cleaner 110 is turned off when the cleaning cycle is completed.
  Accordingly, since the amount of biting of the cleaning brush 113 is set to be large in the cleaning cycle, toner and foreign matter on the conveyor belt 80 are surely detected by the cleaning brush 113 (cleaner position: (2)) of the belt cleaner 110. And is collected in the cleaner case 112.
[0032]
II.Cash register mode
  In order to correct color misregistration, for example, a ladder pattern (registon mark) of each color is formed on the conveyance belt 80, the pitch of the ladder pattern is read by the mark sensor 140, and the registration position of each color is read. This is a mode for performing alignment.
  In this case, in order to cause the toner image to be written on the conveyance belt 80, as shown in FIG. 7, a process substantially similar to the cleaning cycle described above is executed.
[0033]
III.Pro-con mode
  In this mode, in order to correct the density of the image, for example, a patch of each color (Procon mark) is formed on the conveyor belt 80, the density of the patch is read by the mark sensor 140, and the density is adjusted.
  Also in this case, in order to write a toner image on the conveyance belt 80, as shown in FIG. 7, processing similar to the cleaning cycle described above is executed.
[0034]
IV.Print mode
  This is a mode for performing a normal image forming process.
  The recording material is nipped between the suction roll 90 and the conveyance belt 80 and then electrostatically adsorbed to the conveyance belt 80.
  Thereafter, the recording material is conveyed by the conveyance belt 80 and sequentially passes through the transfer portions of the respective image forming units 22 (22a to 22d), so that each color component toner image on the photosensitive drum 31 is transferred by the transfer electric field generated by the transfer roll 50. It is sequentially transferred onto the recording material.
  When the leading end of the recording material enters the fixing device 64 and passes through, the recording material on which the unfixed toner image is fixed is discharged to the storage tray 67 through the discharge roll 66.
[0035]
In this mode, as shown in FIG. 8, the drive control device 130 sets the belt cleaner 110 to the cleaner position: (1) by the position changing mechanism 120 when the image forming signal is turned on. Thereafter, the belt cleaner 110 is turned on (the cleaning brush 113 is driven to rotate), and the belt cleaner 110 is turned off when the image formation is completed.
At this time, since the fog toner is present on the conveying belt 80, the belt cleaner 110 is set to the cleaner position (1), and the amount of biting of the cleaning brush 113 is small.
[0036]
Incidentally, when a jam occurs in the middle of the print mode, the drive control device 130 immediately executes the cleaning cycle after setting the belt cleaner 110 to the cleaner position: (2) as shown in FIG. At the end of the cleaning cycle, the belt cleaner 110 is set to the cleaner position: (1), and then the belt cleaner 110 is turned off.
As described above, according to the present embodiment, cleaning is performed by using the amount of biting of the cleaning brush 113 in the print mode (image formation mode) and in other modes (cleaning cycle, process control mode, and register control mode). The life of the brush 113 is extended.
[0037]
Embodiment 2
FIG. 13 (a) shows a second embodiment of a belt cleaner to which the present invention is applied.
In the figure, a belt cleaner 110 according to the present embodiment shows a bias brush system, and removes toner on the conveyor belt 80 mainly using an electric force.
In this method, a cleaning brush (volume resistance 10) is opposed to the tension roll 82.^Five-10⁸The degree of contact of the toner on the conveyor belt 80 is determined by applying a bias having a polarity opposite to that of the toner (for example, +2 kv, where the tension roll 82 as the opposite roll is grounded) to the cleaning brush 113. To the cleaning brush 113.
The toner adhering to the cleaning brush 113 is applied from the cleaning brush 113 by applying a higher bias (for example, +2.2 kv) than the cleaning brush 113 to the toner removing roll (metal roll) 151 in contact with the cleaning brush 113. The toner is transferred onto the toner removing roll 151.
The toner transferred onto the toner removal roll 151 is scraped off from the roll 151 into the cleaner case (collection box) 112 by mechanical force by bringing the blade 152 into contact with the roll 151.
Reference numeral 153 denotes an eccentric cam of a position changing mechanism that changes the position of the belt cleaner 110.
[0038]
In the present embodiment, the belt cleaner 110 is the same as that in the first embodiment in that the cleaner position is changed by the position changing mechanism. However, instead of or in addition to this, application to the cleaning brush 113 is performed. It is also possible to variably set the cleaning capability of the cleaning brush 113 by changing the bias.
[0039]
Embodiment 3
FIG. 13 (b) shows a third embodiment of a belt cleaner to which the present invention is applied.
In the figure, a belt cleaner 110 according to the present embodiment is of a fur brush type and removes toner on the conveyor belt 80 mainly using mechanical force (brush waist).
In this method, the cleaning brush 113 is always placed in contact with the tension roll 82, the cleaning brush 113 is rotated at a high speed (for example, 1600 rpm), and the toner is removed from the conveying belt 80 by the waist of the cleaning brush 113. Is.
The toner adhering to the cleaning brush 113 causes the flicking member (flicker bar) 155 provided in the cleaner case 112 to contact the cleaning brush 113.EspeciallyIt will fly down.
The scattered toner is sucked by a blower (air inhaler) 156 provided in the cleaner case 112, and collected by the filter 157 by providing a filter 157 or the like in front of the blower 156.
Reference numeral 153 denotes an eccentric cam of a position changing mechanism that changes the position of the belt cleaner 110.
[0040]
In the present embodiment, belt cleaner 110 is the same as that in the first embodiment in that the cleaner position is changed by the position changing mechanism. However, instead of this, or together with this, the rotation speed of cleaning brush 113 is changed. It is also possible to variably set the cleaning capability of the cleaning brush 113.
[0041]
【The invention's effect】
  As described above, according to the present invention, on the premise of an image forming apparatus of a type in which a plurality of image forming units are arranged in parallel, and an image formed by each image forming unit is transferred to the recording carrier side, Since the cleaning brush is always placed in contact with the recording carrier, the background fog generated during image formation can always be cleaned, and the occurrence of residual marks such as toner can be avoided. It becomes possible to always maintain the surface state of the body in a good state free from dirt such as toner, and it is possible to effectively avoid the phenomenon of dirt such as backside dirt on the recording material.
  In addition, according to the present invention, the cleaning capability adjusting means for variably adjusting the cleaning capability of the cleaning brush with respect to the recording conveyance body is provided, and the cleaning capability adjusting means is provided.The amount of biting into the recording carrier of the cleaning brush is variably adjusted.In the normal image forming mode for cleaning the transfer residual image after the normal image forming process, and for controlling the image forming process, a control image is formed on the recording carrier and the control image on the recording carrier is directly cleaned. The cleaning ability is adjusted in the image forming process control mode, and the cleaning ability is set higher than in the normal image forming mode at least in the image forming process control mode so that the control image can be cleaned. The change with time of the brush can be effectively avoided, and the life of the cleaner can be sufficiently extended.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a cleaner according to the present invention and an image forming apparatus using the cleaner.
FIG. 2 is an explanatory diagram showing an overall configuration of Embodiment 1 of an image forming apparatus to which the present invention is applied.
FIG. 3 is an explanatory diagram showing an outline of a layout and a cleaner configuration of a belt cleaner (cleaner) according to the first embodiment.
4 is an explanatory view showing a drive control system of a belt cleaner according to Embodiment 1. FIG.
5A is an explanatory view showing a state of a cleaner position of the belt cleaner according to the first embodiment: (1), and FIG. 5B is an explanatory view showing a state of the cleaner position of the cleaner: (2). is there.
FIG. 6 is a flowchart showing a specific processing content of a drive control system of the belt cleaner according to the first embodiment.
7 is a flowchart showing specific processing contents of a drive control system of the belt cleaner according to Embodiment 1. FIG.
FIG. 8 is a flowchart showing specific processing contents of a drive control system of the belt cleaner according to the first embodiment.
FIG. 9 is an explanatory diagram showing an experimental model regarding the amount of biting of the cleaning brush.
10 is a graph showing a change in the brush diameter over time with respect to the brush operating time when the amount of biting of the cleaning brush is made constant in the experimental model of FIG.
11 is a graph showing the relationship of the change in brush nip width due to the change in brush diameter when the amount of biting of the cleaning brush is made constant in the experimental model of FIG.
12A is an explanatory diagram showing the cleaning efficiency with respect to the brush nip width when the toner coverage is 100%, and FIG. 12B is an explanatory diagram showing the cleaning efficiency with respect to the brush nip width when the toner coverage is 10%.
13A is an explanatory view showing an outline of a belt cleaner according to Embodiment 2, and FIG. 13B is an explanatory view showing an outline of a belt cleaner according to Embodiment 3. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 (1a-1d) ... Image forming unit, 2 ... Recording conveyance body, 3 ... Recording material, 4 ... Transfer means, 5 ... Cleaner, 6 ... Cleaning brush, 7 ... Cleaning ability adjustment means, 8 ... Cleaning ability control means

Claims (7)

A plurality of image forming units are arranged in parallel, and a recording transport body that is circulated and transported to a portion that faces each image forming unit is disposed, and the image forming unit is formed on the recording transport body directly or via a recording material. Used in an image forming apparatus for transferring a transferred image, and in a cleaner for cleaning the recording carrier,
A cleaning brush disposed so as to always contact the recording carrier;
A cleaning ability adjusting means for adjusting the cleaning ability of the cleaning brush with respect to the recording carrier,
The cleaning capacity adjusting means variably adjusts the amount of biting of the cleaning brush into the recording carrier , and controls the image forming process in the normal image forming mode for cleaning the transfer residual image after the normal image forming process. At least image formation so that the control image can be cleaned by adjusting the cleaning capability in the image forming process control mode in which a control image is formed on the recording carrier and the control image on the recording carrier is directly cleaned. A cleaner characterized in that the cleaning capability is set higher in the process control mode than in the normal image formation mode. The cleaner of claim 1,
A cleaner comprising cleaning ability control means for controlling the cleaning ability of the cleaning ability adjusting means in accordance with the state of dirt on the recording and conveying body. The cleaner according to claim 1 or 2,
The cleaning ability adjusting means can be adjusted in two or more stages at least in a contact state. Among the cleaners according to claim 1 or 2, in the method of cleaning the recording transport body mainly using an electric force by applying a bias to the cleaning brush,
The cleaning capability adjusting means variably adjusts the bias applied to the cleaning brush. Among the cleaners according to claim 1 or 2, wherein the recording carrier is cleaned mainly using mechanical force due to the waist of the cleaning brush.
The cleaning capability adjusting means variably adjusts the rotational speed of the cleaning brush. The cleaner according to claim 2,
The cleaning capability control means controls the cleaning capability according to each mode used in non-image formation and in the image forming apparatus.   An image forming apparatus comprising the cleaner according to claim 1.

Images