JP4816821B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus such as a color laser printer.

  In general, as an image forming apparatus such as a laser printer, a plurality of developing units respectively storing different color toners, a plurality of photosensitive drums to which toner is supplied from each of the plurality of developing units via a developing roller, and a plurality of developing units There is known a belt including a belt disposed opposite to the photosensitive drum and a plurality of transfer units that draw toner held by the plurality of photosensitive drums toward the belt. In this image forming apparatus, a plurality of photosensitive drums are arranged in parallel, and when the paper transported by the belt passes between each photosensitive drum and each transfer device, it corresponds to the charging polarity of the toner. By applying a transfer bias to each transfer device, the different color toner held on each photoconductor drum is attracted by each transfer device and sequentially transferred to the paper, and color printing on the paper is performed.

In such an image forming apparatus, in order to facilitate maintenance of the photosensitive drum, the photosensitive drums of the respective colors are integrally held in the photosensitive drum unit, and the photosensitive drum unit can be attached to and detached from the apparatus main body. What is worn is known. Also, an image equipped with a cleaning unit that removes and collects deposits by contacting the conveyor belt in order to remove deposits such as toner and paper dust attached to the conveyor belt due to paper jams. Forming devices are known.
For example, in the image forming apparatus described in Patent Document 1, the photosensitive drum unit is disposed above the conveyance belt, and the cleaning unit is disposed below the conveyance belt through which the sheet does not pass.

Japanese Patent Laid-Open No. 2006-98772

In an image forming apparatus including a cleaning unit, it is necessary to maintain the cleaning unit in order to discard the deposits removed and collected from the transport belt.
However, in the conventional image forming apparatus, since the cleaning unit is disposed below the conveyance belt, there is a problem that the conveyance belt must be removed during maintenance of the cleaning unit, and the maintenance work is complicated.
Further, when the photosensitive drum unit is disposed above the transport belt and the cleaning unit is disposed below the transport belt, there is a problem that the height of the apparatus becomes large and the apparatus becomes large.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus capable of facilitating maintenance work of a cleaning unit and reducing the size of the apparatus.

An image forming apparatus according to the present invention includes an apparatus main body, an image forming unit having a plurality of photosensitive drums arranged in parallel, and the image forming unit, and the apparatus main body along the arrangement direction of the photosensitive drums A drawer frame configured to be capable of being pulled out, a plurality of the photosensitive drums facing each other, a conveyance belt that conveys a recording sheet on a surface facing the photosensitive drums, And a cleaning member that collects deposits adhered to the conveyor belt and an deposit container that accommodates the collected deposits, and is disposed on the same side as the image forming unit with respect to the conveyor belt , and the drawer frame It is spaced a cleaning unit mounted, the cleaning member, from the conveyor belt and the contact position in contact with the conveyor belt And a disjunctive member for moving between a separated position, the drawer frame is withdrawable while the conveyor belt is left in the apparatus main body, the deposit container, the drawer frame drawn In this state, the cleaning member can be attached to and detached from the drawer frame while remaining on the drawer frame, and the cleaning member moves to the separation position when the recording sheet passes over the conveyance belt. to have characterized the Rukoto.

According to this configuration, since the cleaning unit for the transport belt is disposed on the same side as the image forming unit with respect to the transport belt, it is as easy as attaching and detaching the image forming unit from the apparatus main body. Maintenance can be performed. Further, the cleaning unit is configured to be movable between the contact position and the separation position with respect to the transport belt . Since the cleaning member moves to the separation position when the recording sheet passes over the conveyance belt, even if the cleaning unit is arranged on the same side as the image forming unit with respect to the conveyance belt, the recording sheet Does not interfere with transport.

  According to the present invention, it is possible to facilitate the maintenance work of the cleaning unit and to reduce the size of the apparatus.

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. In the drawings to be referred to, FIG. 1 is a cross-sectional view showing an overall configuration of a color printer as an example of an image forming apparatus. FIG. 2 is an enlarged cross-sectional view of the main part showing the structure of the process cartridge and the cleaning unit. 3 is a cross-sectional view taken along the line II of FIG. 4 is a cross-sectional view taken along line II-II in FIG. FIG. 5 is a side view of the cleaning unit. FIG. 6 is a diagram illustrating a state where the drawer unit is pulled out, and FIG. 7 is a diagram illustrating a state where the cleaning unit is detached from the drawer unit.

  In the following description, the direction will be described with reference to the user when using the color printer. That is, in FIG. 1, the left side toward the paper surface is “front side”, the right side toward the paper surface is “rear side”, the rear side toward the paper surface is “left side”, and the front side toward the paper surface is “right side”. To do. In addition, the vertical direction toward the page is defined as the “vertical direction”.

  As shown in FIG. 1, the color printer 1 includes, in the apparatus main body 10, a paper feeding unit 20 that supplies paper P as an example of a recording sheet, and an image forming unit 30 that forms an image on the fed paper P. And a paper discharge unit 90 for discharging the paper P on which the image is formed.

  An upper cover 12 is provided on the upper portion of the apparatus body 10. A front cover 14 that can be opened and closed is provided at the front portion of the apparatus main body 10 so as to be pivotable back and forth with a hinge 14A provided on the lower side as a fulcrum. The upper surface of the upper cover 12 serves as a paper discharge tray 13 for accumulating the paper P discharged from the apparatus main body 10, and a scanner unit 40 described later is provided below the upper cover 12.

  The paper feeding unit 20 is provided in the lower part of the apparatus main body 10, and a paper feeding tray 21 that is detachably attached to the apparatus main body 10, and a paper supply for conveying the paper P from the paper feeding tray 21 to the image forming unit 30. The mechanism 22 is mainly provided. The paper supply mechanism 22 is provided on the front side of the paper supply tray 21 and mainly includes a paper supply roller 23, a separation roller 24, and a separation pad 25.

  In the paper feed unit 20 configured in this way, the paper P in the paper feed tray 21 is separated one by one and sent upward, and passes through between the paper dust removal roller 26 and the pinch roller 27 in the process. After the powder is removed, the direction is changed backward through the conveying roller 28 and supplied to the image forming unit 30.

The image forming unit 30 mainly includes a scanner unit 40, four process cartridges 50, 50,... As an example of an image forming unit, a cleaning unit 100, a transfer unit 70, and a fixing unit 80. .
The four process cartridges 50, 50,... And the cleaning unit 100 are mounted on a drawer frame 15 configured to be detachable from the apparatus main body 10. The drawer frame 15 is formed in a frame shape without a bottom, for example. The drawer frame 15 can be pulled out from the apparatus main body 10 by opening the front cover 14.

  The scanner unit 40 is provided in the upper part of the apparatus main body 10 and includes a laser light emitting unit (not shown), a polygon mirror 41 that is rotationally driven, lenses 42 and 43, a reflecting mirror 44, and the like. As shown in FIG. 1, the laser beam corresponding to each color based on the image data emitted from the laser emission unit passes in the order of the polygon mirror 41, the lens 42, the reflecting mirror 44 corresponding to each color, and the lens 43 corresponding to each color. Alternatively, the light is reflected and irradiated on the surface of the photosensitive drum 53 of the process cartridge 50 corresponding to each color by high-speed scanning.

  The process cartridge 50 is arranged in the front-rear direction between the scanner unit 40 and the transfer unit 70, and is detachably attached to the photosensitive cartridge 51 and the photosensitive cartridge 51 as shown in FIG. And a developing cartridge 61. The process cartridge 50 is detachably mounted on the drawer frame 15.

  The photoreceptor cartridge 51 mainly includes a drum frame 52, a photoreceptor drum 53 that is rotatably supported by the drum frame 52, a charger 54, and a cleaning roller 56.

  When the developing cartridge 61 is mounted on the drum frame 52, an exposure hole 55 that faces the photosensitive drum 53 from above is formed between the developing cartridge 61 and the drum frame 52. A laser beam from the lens 43 of the scanner unit 40 is incident on the exposure hole 55 toward the upper surface of the photosensitive drum 53. The cleaning roller 56 is rotatably provided so as to be in sliding contact with the photosensitive drum 53, and temporarily collects the transfer residual toner T adhering to the photosensitive drum 53 by applying a predetermined voltage. is doing.

  The developing cartridge 61 includes a developing frame 62, a developing roller 63 and a supply roller 64 that are rotatably supported by the developing frame 62, and a layer thickness regulating blade 65, and includes a toner storage chamber 66 that stores toner T. ing.

  Each of the developing cartridges 61 has the same configuration except that the color of the toner T as an example of the developer stored in the toner storage chamber 66 is different.

  As shown in FIG. 1, the transfer unit 70 is provided between the sheet feeding unit 20 and each process cartridge 50, and mainly includes a driving roller 71, a driven roller 72, a conveyance belt 73, and a transfer roller 74. Yes.

The driving roller 71 and the driven roller 72 are arranged in parallel in a spaced manner in the front-rear direction, and a conveyance belt 73 formed of an endless belt is stretched between them. The outer surface of the conveyor belt 73 is in contact with each photosensitive drum 53. In addition, four transfer rollers 74 that sandwich the conveyor belt 73 between the photosensitive drums 53 are arranged inside the conveyor belt 73 so as to face the photosensitive drums 53. A transfer bias is applied to the transfer roller 74 by constant current control during transfer.
A backup roller 75 is disposed inside the transport belt 73 so as to face a cleaning roller 111 of a cleaning unit 100 described later.

  The fixing unit 80 is disposed on the rear side of each process cartridge 50 and the transfer unit 70, and includes a heating roller 81 and a pressure roller 82 that is disposed to face the heating roller 81 and presses the heating roller 81.

The cleaning unit 100 is a device that removes toner T as an example of adhesion that has adhered to the conveyance belt 73, and is disposed behind the plurality of process cartridges 50 in parallel therewith. The cleaning unit 100 includes a cleaning unit 110 that collects the toner T adhering to the conveyance belt 73 and a waste toner box 120 as an example of an adhering matter container that stores the collected toner T. As with the process cartridge 50, the cleaning unit 100 is configured to be detachable from the drawer frame 15.
In addition to the paper jam, the toner T may adhere to the conveyance belt 73 by a so-called patch test for testing the printing density, color tone, and color misregistration.

As shown in FIGS. 2 and 3, the cleaning unit 110 includes a cleaning roller 111 as an example of a cleaning member, a collection roller 112, a blade 113, and a transport unit 114.
The cleaning roller 111 is a member that contacts the conveying belt 73 and removes the toner T. The cleaning roller 111 is a foaming roller such as silicon or urethane formed by covering a metal roller shaft with a roller body made of a conductive foaming material. It is. The cleaning roller 111 is configured to be detachable from the conveyance belt 73.

  The collection roller 112 is, for example, a metal roller made of a hard material such as a metal that comes into pressure contact with the cleaning roller 111, and is provided to be rotated obliquely upward on the rear side of the cleaning roller 111. The blade 113 is a member that presses against the collection roller 112 and scrapes off the toner T, and is provided on the rear side of the collection roller 112. The transport unit 114 is a path for transporting the toner T scraped off by the blade 113 to the waste toner box 120, and a first auger 114 a extending in the left-right direction is disposed inside the transport unit 114.

  The waste toner box 120 includes a storage unit 121 that stores the collected toner T, and an input unit 122 that inputs the toner T sent from the cleaning unit 110 into the storage unit 121. The storage unit 121 has a substantially parallelogram shape in cross-sectional view, and a lower end portion thereof is connected to the cleaning unit 110. The input unit 122 is a passage that communicates the transport unit 114 and the storage unit 121, and a second auger 122 a that extends obliquely in the vertical direction is disposed therein. The input unit 122 is provided on the left side of the transport unit 114 and the storage unit 121.

  As shown in FIG. 4, on the right side (left side in FIG. 4) of the waste toner box 120, a light emitting unit 124 that emits a measurement beam for measuring the amount of toner stored in the waste toner box 120 is disposed. . On the left side of the waste toner box 120, a light receiving unit 125 that receives the measurement light beam is disposed. The left and right side walls 123 of the waste toner box 120 are formed with through holes 123a and 123b for transmitting the measurement light beam.

As shown in FIG. 5, on the side walls 110 a (only the right side is shown in FIG. 5) on both sides of the cleaning unit 110, there are provided rotating members 115 that bring the cleaning roller 111 into contact with and away from the conveyance belt 73. . Further, a long hole 111b that pivotally supports the rotating shaft 111a of the cleaning roller 111 is formed in the side wall 110a. The long hole 111 b is formed substantially along the rotation direction of the rotation member 115. The rotation member 115 has a substantially fan shape, and one end side (the center side of the fan) is pivotally supported by the side wall 110a. The rotation axis of the rotation member 115 is collinear with the rotation axis of the collection roller 112. Therefore, the cleaning roller 111 rotates around the rotation axis of the collection roller 112 and can be satisfactorily separated from the conveying belt 73.
Further, an arcuate engagement hole 115a that engages with the end of the rotation shaft 111a protruding from the long hole 111b is formed on the other end side (the arc side of the fan) of the rotating member 115. The rotating member 115 is provided on both the left and right sides of the cleaning unit 110.

Paper detection sensors for detecting the passage of the paper P are provided between the conveyance roller 28 and the conveyance belt 73 and between the conveyance belt 73 and the fixing unit 80 (not shown).
Based on the detection signals from the two paper sensors, the control unit that separates the cleaning roller 111 from the conveying belt 73 determines whether or not the paper P is between the two paper detection sensors. The roller 111 is separated from the conveyor belt 73, and if not, the cleaning roller 111 is brought into contact with the conveyor belt 73. Note that, as will be described later, there is a case where the operation of bringing the cleaning roller 111 into and out of contact with the conveyance belt 73 is performed regardless of whether or not the sheet P is between the two sheet detection sensors.

  In the image forming unit 30 configured as described above, first, the surface of each photosensitive drum 53 is uniformly charged positively by the charger 54, and then laser light corresponding to each color emitted from the scanner unit 40 is obtained. Is exposed. As a result, the potential of the exposed portion is lowered, and an electrostatic latent image based on the image data is formed on each photosensitive drum 53.

  Further, the toner T in the toner storage chamber 66 is supplied to the developing roller 63 by the rotation of the supply roller 64, and enters between the developing roller 63 and the layer thickness regulating blade 65 by the rotation of the developing roller 63 and has a constant thickness. Is carried on the developing roller 63 as a thin layer. Here, the toner T carried on the developing roller 63 is frictionally charged positively between the supply roller 64 and the developing roller 63 or between the developing roller 63 and the layer thickness regulating blade 65.

  The toner T carried on the developing roller 63 is supplied to the electrostatic latent image formed on the photosensitive drum 53 when the developing roller 63 comes into contact with the photosensitive drum 53. As a result, the toner T is selectively carried on the photosensitive drum 53 to visualize the electrostatic latent image, and a toner image is formed by reversal development.

  Then, the paper P supplied onto the conveyance belt 73 passes between each photosensitive drum 53 and each transfer roller 74 disposed inside the conveyance belt 73, thereby forming on each photosensitive drum 53. The transferred toner image is transferred onto the paper P. When the paper P passes between the heating roller 81 and the pressure roller 82, the toner image transferred onto the paper P is thermally fixed.

  As shown in FIG. 1, the paper discharge unit 90 includes a plurality of pairs of conveyance rollers in a paper discharge side conveyance path of the paper P and a paper P discharge port. The paper P on which the toner image has been transferred and heat-fixed is transported along a paper discharge-side transport path by transport rollers, is discharged outside the apparatus main body 10, and is accumulated in the paper discharge tray 13.

Next, the operation of the cleaning unit will be described with reference to FIG.
As shown in FIG. 5A, when the paper P is transported by the transport belt 73, based on the outputs of the two paper detection sensors, the control unit controls the paper between these sensors, that is, on the transport belt 73. Determine that P is present. Then, the control unit transmits an operation signal to an actuator (not shown) connected to the rotation member 115 to rotate the rotation member 115 upward. As a result, the cleaning roller 111 is lifted away from the conveyor belt 73 via the rotating shaft 111 a engaged with the rotating member 115. Therefore, the conveyance of the paper P is not hindered by the cleaning roller 111.

  As shown in FIG. 5B, when the sheet P is not conveyed by the conveyance belt 73, the control unit determines that there is no sheet P on the conveyance belt 73 based on the outputs of the two sheet detection sensors. If other predetermined conditions for starting cleaning are satisfied, an operation signal is transmitted to an actuator (not shown) connected to the rotation member 115 to rotate the rotation member 115 downward. As a result, the cleaning roller 111 comes into contact with the transport belt 73 via the rotating shaft 111a engaged with the rotating member 115, and the transport belt 73 can be cleaned.

Next, the operation of the cleaning unit when not based on the output of the paper detection sensor will be described.
When the main power is turned on, or immediately after closing the front cover 14 after paper jam processing or replacement of various cartridges, the control unit (not shown) first sends an operation signal to an actuator (not shown) connected to the rotating member 115. Then, the rotating member 115 is rotated upward. As a result, the cleaning roller 111 moves upward through the rotating shaft 111 a engaged with the rotating member 115 and is separated from the transport belt 73. In this state, even if the conveyance belt 73 and other sheet conveyance means are driven for a predetermined time and the sheet P remains in the image forming apparatus, the sheet P is discharged to the sheet discharge tray 13. At this time, since the cleaning roller 111 is separated from the transport belt 73, there is no obstacle to the discharge of the paper P. This series of processing is called a paper discharge mode. Next, a control unit (not shown) transmits an operation signal to an actuator (not shown) connected to the rotation member 115 to rotate the rotation member 115 downward. As a result, the cleaning roller 111 moves downward through the rotating shaft 111 a engaged with the rotating member 115 and contacts the transport belt 73. In this state, the control unit rotates the conveyor belt 73.

  At this time, the roller shaft of the backup roller 75 is grounded, and a negative bias is applied to the cleaning roller 111, for example, and a lower negative bias is applied to the recovery roller 112. As a result, the toner T adhering to the conveyance belt 73 moves to the cleaning roller 111 near the position where the cleaning roller 111 and the backup roller 75 face each other by the bias suction force and the contact force of the cleaning roller 111. Then, the toner T carried on the cleaning roller 111 moves to the collection roller 112 by a bias suction force, and the toner T carried on the collection roller 112 is scraped off by the blade 113 and finally enters the conveyance unit 114. It is thrown. The toner T put into the transport unit 114 is transported to the input unit 122 by the first auger 114a. The toner T conveyed to the input unit 122 is input and stored in the storage unit 121 by the second auger 122a.

  At this time, a predetermined voltage for returning the toner T to the photosensitive drum 53 (positive bias that moves the positively charged toner T to the photosensitive drum 53) is applied to the cleaning roller 56 provided in the photosensitive cartridge 51 for a predetermined time. To do. The toner T returned to the photosensitive drum 53 is discharged to the transport belt 73 by applying a negative transfer bias that moves the toner T to the transport belt 73 to the transfer roller 74. Thereafter, the toner T reaches the cleaning roller 111 with the movement of the conveyance belt 73 and is collected by the cleaning roller 111. The collected toner T is stored in the storage unit 121 of the waste toner box 120. In this way, the cleaning of the toner T temporarily held by the cleaning roller 56 provided in the photoconductor cartridge 51 is completed. This series of processing is called a cleaning mode.

Next, an electrostatic latent image having a predetermined patch pattern is formed on the photosensitive drum 53 by the scanner unit 40. The electrostatic latent image is developed with toner T carried on the developing roller 63. Next, a patch pattern formed of toner T is formed on the conveyance belt 73 by a negative transfer bias applied to the transfer roller 74.
The formed patch pattern reaches the patch pattern sensor as the transport belt 73 moves, and various measurements are performed by the patch pattern sensor. The patch pattern sensor is disposed below the driven roller 72 at a position facing the driven roller via the conveying belt 73, and is composed of a light emitting element and a light receiving element. For example, the image density and color misregistration between the colors are detected. It is to be measured.

When the patch pattern formed on the conveyance belt 73 passes through the cleaning roller 111, the cleaning roller 111 is controlled to be separated from the conveyance belt 73, and the cleaning roller 111 does not disturb the patch pattern.
At the timing after all the patch patterns have passed through the position facing the cleaning roller 111, the cleaning roller 111 contacts the transport belt 73. Thus, the toner T forming the patch pattern makes a round on the transport belt 73, is collected by the cleaning roller 111, and is stored in the storage unit 121 of the waste toner box 120. This series of processing is called a patch pattern measurement mode.

In this way, the three processes of the paper discharge mode, the cleaning mode, and the patch pattern measurement mode are a series of apparatus startup processes that are performed when the main power is turned on or after the front cover is opened and closed.
Here, the patch pattern sensor may be disposed between the photosensitive drum 53 and the cleaning roller 111. In this case, the image forming apparatus becomes large in the front-rear direction, but there is an advantage that the time required for the patch pattern measurement mode can be shortened because the patch pattern does not need to go around on the transport belt.

  As shown in FIG. 4, when the measurement light beam from the light emitting unit 124 is blocked by the toner T stored in the storage unit 121 and is no longer detected by the light receiving unit 125, a control unit (not shown) is provided in the apparatus main body 10. A message prompting maintenance of the cleaning unit 100 is displayed on the displayed display device.

Next, maintenance of the cleaning unit 100 will be described with reference to FIG.
When maintenance of the cleaning unit 100 is performed, the drawer frame 15 is pulled out after opening the front cover 14 as shown in FIG. As a result, the four process cartridges 50 and the cleaning unit 100 mounted on the drawer frame 15 are removed from the apparatus main body 10. Then, as shown in FIG. 7, the cleaning unit 100 is detached from the drawer frame 15 and replaced with a new cleaning unit 100, or the toner T collected in the storage unit 121 is discarded.

  When performing maintenance of the process cartridge 50, as in the case of the cleaning unit 100, after opening the front cover 14, the drawer frame 15 is pulled out, the process cartridge 50 is detached from the drawer frame 15, and a new process cartridge 50 is obtained. Replace with.

According to the color printer 1 configured as described above, the cleaning unit 100 can be maintained by the same procedure as the maintenance of the process cartridge 50. That is, the cleaning unit 100 can be maintained with the ease of pulling out the drawer frame 15 in parallel with the transport direction of the paper P and performing maintenance as it is.
Further, since the cleaning unit 100 is arranged in parallel with the four process cartridges 50, the height dimension can be reduced by the amount of the cleaning unit 100 as compared with the conventional image forming apparatus.
In the color printer 1 of the present embodiment, the cleaning roller 111 is separated from the transport belt after the leading end of the paper P passes through the photosensitive drum 53 disposed immediately before the cleaning roller 111. This will not hinder the transport. In other words, the toner image on the paper P is not soiled.

Next, a second embodiment will be described. Note that in the following description of the embodiment, a description will be given mainly of parts different from the first embodiment, and description of common parts will be omitted or simplified.
FIG. 8 is a cross-sectional view showing the main part of the color printer according to the second embodiment.
As shown in FIG. 8, the color printer according to the second embodiment is the process cartridge on the most downstream side in the paper transport direction among the four process cartridges 50, 50, 50, 200 arranged in parallel on the drawer frame 15. The configuration of 200 is different from that of the first embodiment.

  That is, the process cartridge 200 includes a photoreceptor cartridge 251, a developing cartridge 261, a cleaning unit 210, and a waste toner box 220. The developing cartridge 261 is integrated with the waste toner box 220 via the connecting portion 201. The connecting unit 201 is, for example, a member that connects the housing of the developing cartridge 261 and the housing of the waste toner box 220. Here, the developing cartridge 261 integrated with the waste toner box 220 is preferably a black toner developing cartridge in which black toner T is accommodated.

  According to such a configuration, the waste toner box 220 and the cleaning unit 210 that are cleaning units are attached to and detached from the drawer frame 15 together with the developing cartridge 261. Therefore, maintenance of the cleaning unit becomes easier. Further, since the waste toner box 220 is replaced integrally with the developing cartridge 261, the upper limit of the capacity of the waste toner box 220 can be estimated, and the capacity of the waste toner box 220 can be reduced, or the amount of toner in the waste toner box 220 can be reduced. It is possible to dispense with a means for measuring. Furthermore, when the waste toner box 220 and the cleaning unit 210 are integrated with the developing cartridge 261, the cleaning roller 111 that comes in contact with and separates from the image becomes a problem. In this embodiment, only the cleaning roller 111 moves and the waste toner box 220 moves. Therefore, there is no problem even if the connecting portion 201 is integrated.

Next, a third embodiment will be described.
FIGS. 9A and 9B are cross-sectional views showing a color printer cleaning unit according to the third embodiment, where FIG. 9A shows a combined state and FIG. 9B shows a separated state.
As shown in FIG. 9B, the cleaning unit 300 according to the third embodiment is different from the first embodiment in that the cleaning unit 310 and the waste toner box 320 are configured to be separable. .

  The cleaning unit 310 includes a cleaning roller 311 as a cleaning member, a collection roller 312, a blade 313, and a transport unit 314. A first auger 314 a is disposed inside the transport unit 314. In addition, a rotation member 315 is provided on the side surface of the cleaning unit 310.

  The waste toner box 320 includes a storage unit 321 and an input unit 322. A second auger 322 a is disposed inside the input unit 322. As shown in FIGS. 9A and 9B, the lower end of the second auger 322a extends below the lower end of the waste toner box 320, and when the waste toner box 320 is attached to the cleaning unit 310, It is arranged in the transport unit 314.

With this configuration, only the waste toner box 320 can be removed from the apparatus main body 10 (from the drawer frame 15) during maintenance of the cleaning unit 300. Therefore, at the time of maintenance, for example, the waste toner box 320 clogged with the toner T can be discarded and a new waste toner box 320 can be attached to the cleaning unit 310. In this way, hands and the like are not soiled during maintenance, and the cleaning unit 310 can be used continuously, so that maintenance can be facilitated and costs can be reduced.

  In the third embodiment, the cleaning unit 310 may be configured so as not to be detachable from the drawer frame 15. In this way, maintenance of the cleaning unit 310 is facilitated.

Next, a fourth embodiment will be described.
FIG. 10 is an enlarged cross-sectional view of the main part of the color printer according to the fourth embodiment, where (a) shows a state in which a developing cartridge is attached, and (b) shows a state in which the developing cartridge is removed.
As shown in FIG. 10, the color printer according to the fourth embodiment is provided with a waste toner box 421 for storing waste toner in the developing cartridge 461 of the adjacent process cartridge 450, not in the cleaning unit 400. This is different from the first embodiment.

The cleaning unit 400 includes a cleaning unit 410 and an input unit 420.
The cleaning unit 410 includes a cleaning roller 411 that is an example of a cleaning member, a collection roller 412, a blade 413, and a transport unit 414. A first auger 414 a is arranged inside the transport unit 414.
The input unit 420 inputs the toner T in the transport unit 414 into the waste toner box 421 and extends obliquely upward and forward from the left side of the cleaning unit 410. The input unit 420 includes a cylindrical communication unit 422 that allows the conveyance unit 414 and the waste toner box 421 to communicate with each other, and a second auger 422 a installed in the communication unit 422. An opening 422b is formed above the left side of the communication portion 422.

The process cartridge 450 includes a photosensitive cartridge 451 and a developing cartridge 461.
The developing cartridge 461 has a waste toner box 421 that is a compartment for storing waste toner above the toner storage chamber 66. In the waste toner box 421, a third auger 421a for conveying the toner T in the left-right direction is disposed. An opening 421 b for communicating with the communication portion 422 is formed on the left side of the waste toner box 421.

As shown in FIG. 10 (a), when set in the drawer frame 15 of the developing cartridge 461, the left side of the developing cartridge 461, the upper end of the communicating portion 422 is disposed adjacent. As a result, the conveyance unit 414 and the waste toner box 421 are communicated with each other via the communication unit 422.

According to such a configuration, since the waste toner box 421 is provided in the developing cartridge 461, the waste toner box 421 can be replaced simultaneously with the replacement of the developing cartridge 461. In addition, the structure of the cleaning unit 400 can be simplified, and the cleaning unit 400 can be fixed to the drawer frame 15. In this case as well, as in the second embodiment, the capacity required for the waste toner box 421 can be estimated based on the capacity of the toner storage chamber 66 of the developing cartridge 461. Accordingly, it is possible to reduce the capacity of the waste toner box 421 and to omit means for measuring the capacity of the waste toner box 421. Further, in the configuration of the present embodiment, since the input unit 420 does not move with respect to the cleaning roller 411 being separated, the configuration can be simplified.

Next, a fifth embodiment will be described.
FIG. 11 is an enlarged cross-sectional view of a main part of a color printer according to the fifth embodiment.
As shown in FIG. 11, the color printer according to the fifth embodiment is different from the first embodiment in the structure of the cleaning unit 500. Specifically, the cleaning unit 500 includes a belt-shaped transport device 530 instead of an auger as a device for transporting the toner T from the cleaning unit 510 to the waste toner box 520.

The cleaning unit 500 includes a cleaning unit 510 and a waste toner box 520.
The cleaning unit 510 includes a cleaning roller 511 that is a cleaning member, a collection roller 512, a blade 513, and a transport unit 514. The upper part of the transport unit 514 communicates with the storage unit 521 of the waste toner box 520 in the left-right direction. Further, a belt-shaped transport device 530 is disposed across the transport unit 514 and the storage unit 521.

The conveyance device 530 mainly includes an adhering material conveyance belt 531, a plurality of protrusions 532, a driving roller 534, and a driven roller 533.
The driving roller 534 extends in the left-right direction at the lower part of the transport unit 514 and is rotated by a rotating device (not shown). The driven roller 533 extends in the left-right direction above and in front of the storage portion 521. The adhering matter transport belt 531 is a wide endless belt in the left-right direction, and is stretched between the driving roller 534 and the driven roller 533. The adhering matter conveyance belt 531 is bent along the rear wall of the conveyance unit 514, the rear wall of the storage unit 521, and the upper wall of the storage unit 521. A plurality of protrusions 532 extending in the left-right direction are provided at equal intervals on the surface of the adherent conveyance belt 531. The toner T that has entered the transport unit 514 is lifted up by the protrusions 532 and is put into the storage unit 521 from the upper part of the storage unit 521.

The cleaning unit 100 of the first embodiment, the toner T is easily biased to the left side of the storage portion 121, according to the cleaning unit 500 of the fifth embodiment, the belt-type conveying unit 530 extending in the lateral direction, Since the toner T is supplied over the entire left and right direction of the storage unit 521, the toner T is stored without being biased left and right.

Next, a sixth embodiment will be described.
FIG. 12 is a cross-sectional view of a color printer according to the sixth embodiment.
In the color printer 1 according to the sixth embodiment, as shown in FIG. 12, the cleaning unit 600 is arranged in parallel upstream of the four process cartridges 50 in the paper transport direction. It is different from the form.

The cleaning unit 600 includes a cleaning unit 610 and a waste toner box 620.
The cleaning unit 610 includes a cleaning roller 611 as an example of a cleaning member, a collection roller 612, a blade 613, and a transport unit 614. A first auger 614 a is disposed inside the transport unit 614.
The waste toner box 620 includes a storage unit 621 and an input unit 622. A second auger 622 a is disposed inside the input unit 622.
A cleaning roller 6 is provided between the driving roller 71 and the most upstream transfer roller 74.
11 is disposed opposite to the backup roller 75.

  For example, the cleaning roller 611 contacts the conveyance belt 73 when the paper supply mechanism 22 is stopped, and is separated from the conveyance belt 73 when the paper supply mechanism 22 is operated. The operating state of the paper supply mechanism 22 is detected by a control unit (not shown), for example.

  According to such a configuration, since the cleaning unit 600 is arranged in parallel with the four process cartridges 50 on the upstream side in the paper conveyance direction, compared with the case where the cleaning unit 600 is arranged below the transfer unit 70. The height dimension of the color printer 1 can be reduced. Further, according to the present embodiment, the toner T placed on the conveyance belt 73 in the patch pattern measurement mode does not pass the cleaning roller 611 during the measurement of the patch pattern, so that the cleaning roller 611 needs to be separated from the conveyance belt 73. There is no. In addition, since the waste toner box 620 is adjacent to the developing cartridge 61, the waste toner box 620 and the developing cartridge 61 can be easily integrated as shown in FIG. 13 as in the second embodiment.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to these embodiment, In the range which does not deviate from the meaning of this invention, it can change suitably.

  For example, in each of the embodiments described above, the roller-shaped cleaning roller 111 has been described as an example of the cleaning member. However, the present invention is not limited to this, and a blade-shaped or brush-shaped cleaning member may be used. Good. However, the cleaning member is preferably in the form of a roller so that it can be easily separated from and brought into contact with the conveyor belt.

  Further, the present invention can be applied not only to a color printer as exemplified in the embodiment, but also to a copying machine or a multifunction machine, and is not limited to an image forming apparatus that performs exposure with a laser. The present invention can also be applied to an image forming apparatus that performs exposure.

1 is a cross-sectional view illustrating an overall configuration of a color printer as an example of an image forming apparatus. It is a principal part expanded sectional view which shows the structure of a process cartridge and a cleaning unit. It is the II sectional view taken on the line of FIG. It is the II-II sectional view taken on the line of FIG. It is a side view of a cleaning unit. It is a figure which shows the state which pulled out the drawer unit. It is a figure which shows the state which removed the cleaning unit from the drawer unit. It is sectional drawing which shows the principal part of the color printer concerning 2nd Embodiment. It is sectional drawing which shows the cleaning unit of the color printer which concerns on 3rd Embodiment, (a) has shown the combined state, (b) has each shown the separated state. FIG. 10 is an enlarged cross-sectional view of a main part of a color printer according to a fourth embodiment, where (a) shows a state where a developing cartridge is attached, and (b) shows a state where the developing cartridge is removed. It is a principal part expanded sectional view of the color printer which concerns on 5th Embodiment. It is sectional drawing of the color printer which concerns on 6th Embodiment. It is a figure which shows the modification of 6th Embodiment.

1 Color printer (image forming device)
DESCRIPTION OF SYMBOLS 10 Apparatus main body 15 Drawer frame 20 Paper feed part 30 Image formation part 40 Scanner part 50 Process cartridge (image formation unit)
51 Photosensitive Cartridge 53 Photosensitive Drum 61 Developing Cartridge 70 Transfer Unit 73 Conveying Belt 80 Fixing Unit 100 Cleaning Unit 110 Cleaning Unit 111 Cleaning Roller (Cleaning Member)
115 Rotating member 120 Waste toner box (attachment container)
P paper (recording sheet)

Claims (6)

The device body;
An image forming unit having a plurality of photosensitive drums arranged in parallel;
A drawer frame mounted with the image forming unit and configured to be able to be pulled out to the apparatus main body along the arrangement direction of the photosensitive drum;
A conveying belt that is disposed to face the plurality of photosensitive drums and conveys a recording sheet on a surface facing the photosensitive drum ;
A cleaning member that contacts the conveyor belt and collects deposits adhered to the conveyor belt; and a deposit container that accommodates the collected deposits, and is the same as the image forming unit with respect to the conveyor belt A cleaning unit disposed on the side and mounted on the drawer frame ;
A separation member that moves the cleaning member between a contact position that contacts the conveyance belt and a separation position that is separated from the conveyance belt , and
The drawer frame can be pulled out with the conveyor belt left in the apparatus body,
The deposit container is detachable from the drawer frame with the cleaning member left in the drawer frame in a state where the drawer frame is pulled out.
The image forming apparatus , wherein the cleaning member moves to the separation position when a recording sheet passes over the conveying belt .     The image according to claim 1, wherein the image forming unit and the cleaning unit are configured to be able to be pulled out integrally in a direction parallel to a conveyance direction of a recording sheet conveyed on the conveyance belt. Forming equipment. The image forming unit includes a plurality of developer cartridges that store a developer corresponding to each color,
The image forming apparatus according to claim 2, wherein the cleaning unit is configured integrally with the adjacent developer cartridge. The image forming unit includes a plurality of developer cartridges that store a developer corresponding to each color,
The image forming apparatus according to claim 2, wherein the deposit container is configured integrally with the adjacent developer cartridge, and the deposit container and the cleaning member are separable. . The cleaning member, an image forming apparatus according to any one of claims 1 to 4, characterized in that a cleaning roller. The cleaning member has a cleaning roller that contacts the conveyor belt, and a recovery roller that contacts the cleaning roller and collects the deposits attached to the cleaning roller,
The said separating member has a rotation member which engages with the said cleaning roller and can be rotated centering | focusing on the rotating shaft on the same straight line as the rotating shaft of the said collection roller. Item 5. The image forming apparatus according to any one of Items 4 to 5 .

Images