JP2009139927A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily attach and detach each section of an image forming apparatus, while suppressing the cost. <P>SOLUTION: An enclosure 2 includes: an image forming unit 12 including image carriers 12Y, 12M, 12C and 12K; paper feeding units 10 and 10; an exposure unit 11; an intermediate transfer unit 13; and toner cartridges 14Y, 14M, 14C and 14K. The paper feeding unit 10 is configured so that a transfer paper being consumables can be supplied from the front part of the enclosure 2, the image forming unit 12 is configured so that a process unit including a photoreceptor being consumables can be replaced from the front part of the enclosure 2 and it is configured so that the toner cartridges being consumables can be replaced from the front part of the enclosure 2. The intermediate transfer unit 13 is configured so as to be attached and detached from the right side of the enclosure orthogonal to the replacement direction of the consumables and the exposure unit 11 is configured so as to be attached and detached from the left side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus, and particularly includes an image forming unit including a plurality of image carriers, a paper feeding unit, an exposure unit, an intermediate transfer unit, and a toner supply unit in a housing, and replacement replacement of consumables. Further, the present invention relates to an image forming apparatus in which each unit can be attached to and detached from a casing for maintenance or the like.

  As an example of the image forming apparatus as described above, Patent Document 1 discloses that a front frame and an intermediate frame that holds a process cartridge are coaxially attached to a boss portion opening of a main body frame that is a non-moving portion housing. The intermediate frame has the same rotation fulcrum, and there is no interference between parts when opening and closing the front frame. The process cartridge can be easily attached and detached by opening the front frame and rotating the intermediate frame. An image forming apparatus is described in which other units such as a color developing unit and a black developing unit can be replaced without removing a process cartridge by opening the front frame and the intermediate frame together.

  Patent Document 2 discloses an image forming apparatus in which a sheet feeding unit, an exposure unit, an image forming unit, an intermediate transfer unit, a fixing unit, and a sheet discharge stacking unit are arranged in this order from the lower side of the apparatus, and the sheet conveyance path is substantially vertical. The intermediate transfer means within a range of an angle of 15 degrees on the upper side and an angle of 15 degrees on the lower side with respect to the horizontal direction of the image forming apparatus after opening the rotating portion for opening the sheet conveying path. Describes an image forming apparatus configured to be detachable from the image forming apparatus from the opening direction of the rotating portion.

JP-A-11-030942 JP 2006-171534 A

  However, since the apparatus disclosed in Patent Document 1 has a configuration including an intermediate frame, there is a concern that the cost may increase. Further, in the apparatus disclosed in Patent Document 2, since a plurality of units are attached / detached using the same route as a guide, the order of attaching / detaching units occurs, and only the units arranged at the back side in the take-out direction are used. Even when it is desired to replace the unit, the unit on the front side in the take-out direction, that is, the unit on the front side must be removed and placed outside, which may be troublesome.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus capable of easily attaching and detaching each part of the apparatus while suppressing costs.

  The image forming apparatus of the present invention includes an image forming unit including an image carrier, a paper feeding unit that supplies transfer paper to the image forming unit, and an image carrier of the image forming unit exposed in the housing. An exposure unit for forming an image, a developing device for developing a latent image formed on the image carrier with toner, an intermediate transfer unit for intermediate transfer of a toner image on the image carrier developed by the developing device, and the development A toner unit that supplies toner to the apparatus is provided. From the front side opening of the housing, transfer paper can be supplied to the paper feeding unit, the image forming unit can be replaced, and the toner supply unit replaces a toner cartridge. The intermediate transfer unit can be attached / detached from one side opening of the left and right sides of the housing, and the exposure unit can be attached / detached from the other side opening of the left and right sides of the housing. .

  Further, the intermediate transfer portion may be configured to be smaller than the height dimension on the front side in the entry direction into the housing and smaller than the height dimension on the rear side in the entry direction.

  The intermediate transfer portion is configured by looping an endless intermediate transfer belt around a plurality of rollers, and the intermediate transfer belt looped around the plurality of rollers is a portion on the rear 17 side in the entry direction into the housing. The one tension roller is applied from the outside to give a predetermined tension, and the one tension roller is lower in the height direction in the vicinity of the roller located most rearward in the entry direction into the housing. It can be set as the structure located in the position.

  The intermediate transfer unit includes a cleaning device that collects waste toner removed from the intermediate transfer belt, and the cleaning device is disposed on the front side in a direction in which the intermediate transfer unit enters the housing, and the cleaning device The operation can be performed from the side where the exposed portion is taken out after the exposed portion is taken out.

  The cleaning device may include a waste toner tank that stores waste toner collected from the intermediate transfer belt, and the waste toner tank may be disposed below the cleaning device and may have a vertically long cylindrical shape. it can.

  The waste toner tank may be separated from the cleaning device, and the waste toner tank may be extended to the vicinity of the upper part of the exposure unit to increase the volume.

  Furthermore, in the image forming apparatus of the present invention, the exposure unit can be configured with a detachable part that can be attached to and detached from the casing, and a fixed part to the casing that cannot be removed from the casing.

  It is also possible to lower the position of the paper supply roller provided in the paper supply unit to the vicinity of the lowest part of the position of the removable part of the exposure unit.

  According to the image forming apparatus of the present invention, the part where the consumables are frequently replaced can be operated from the front side of the image forming apparatus, while the replacement frequency is low or the lifetime is the same as that of the image forming apparatus. Since the part is operated from the side of the apparatus, there is an effect that the consumables can be easily replaced and the apparatus can be attached and detached without erroneous operation by the user while suppressing the cost. It is also possible to have a structure in which the height of the apparatus is suppressed.

  The best mode for carrying out the present invention will be described below with reference to the embodiments shown in the drawings.

  In the following description, a printer is taken as an example of the image forming apparatus. However, the present invention is not limited to this, and may be a copier, a facsimile, or a multifunction machine having a plurality of these functions.

  The image transfer system is not limited to the intermediate transfer system, and a direct transfer system is also possible. Further, the image forming method, the number of colors, and the like are not limited to the tandem type image forming apparatus.

  In the embodiments described below, examples of paper feeding, exposure, an image forming unit, an intermediate transfer unit, and toner are shown from the lower part. It may be configured to perform exposure.

  FIG. 1 is a schematic sectional view showing a color printer as an embodiment of an image forming apparatus according to the present invention, and FIG. 2 is a perspective view showing an example of a housing structure of the apparatus of FIG. The color printer 1 according to the present embodiment is a so-called in-cylinder discharge type device in which the discharge destination of the transfer paper after fixing is in the cylinder, for example, based on an image signal corresponding to image information received from the outside. Forming processing is possible, and in addition to plain paper, which is generally used for copying, etc., OHP sheets, cards, postcards and other thick paper, and envelopes can be used to form images on sheet-like recording media. Is something.

  In the housing 2, a plurality of sheets corresponding to the respective colors of the paper feeding units 10, 10, the exposure unit 11, yellow (Y), magenta (M), cyan (C), and black (K) in order from the bottom of the figure. Image bearing units (photosensitive drums) 12Y, 12M, 12C, and 12K, image forming unit 12, intermediate transfer unit 13, yellow (Y), magenta (M), cyan (C), and black (K) toners Toner cartridges 14 (14Y, 14M, 14C, and 14K) are disposed. In the figure, 5 is a document reading unit, 8 is a fixing device, and 17 is a paper discharge unit. Reference numeral 50 denotes a paper feed cassette provided in the paper feed unit 10.

  The sheet feeding units 10 and 10 are configured in two stages, and each sheet feeding unit 10 is provided with a sheet feeding cassette 50 and a sheet feeding roller 32. The exposure unit 11 includes a light source, an optical system, and the like, and exposes the photosensitive drums 12Y, 12M, 12C, and 12K based on control of the host device. The exposure unit 11 will be described later with reference to FIG. The intermediate transfer unit 13 is configured by winding an endless intermediate transfer belt 41 around a driving roller 42 and turning rollers 43 to 45.

  The transfer paper stored in the paper supply unit 10, the photosensitive drums 12Y, 12M, 12C, and 12K of the image forming unit 12 and the toner cartridges 14Y, 14M, 14C, and 14K are consumables, and the degree of wear is a reference value. When it exceeds, it will be replaced. The intermediate transfer unit 13 is configured to be detachable from the right side of the casing 2 orthogonal to the direction of replacement of the consumables, and the exposure unit 11 is configured to be detachable from the left side of the diagram. This detachable structure will be described later.

  In the present invention, the order in which the four image forming units 12 are arranged, that is, the color order of magenta (M), cyan (C), yellow (Y), and black (K) is not limited.

  The color printer shown in FIG. 9 is a conventional color printer shown for comparison, and is a tandem type full-color printer of an intermediate transfer system as in the apparatus of FIG. Also in this printer, an intermediate transfer belt 41 that constitutes the intermediate transfer unit 13 is wound around a plurality of rollers at approximately the center of the housing 2, and below the paper supply unit 10, the exposure unit 11, and magenta ( Four image forming units 12 corresponding to each color of M), cyan (C), yellow (Y), and black (K) are provided side by side. The plurality of image forming units 12 correspond to colors of yellow (Y), magenta (M), cyan (C), and black (K) toners, and each image forming unit 12 is also photosensitive as an image carrier. A body drum 1 is provided.

  In the color printer shown in FIG. 9, a plurality of units (for example, the intermediate transfer unit 13 and the exposure unit 11) are attached and detached in the same path, specifically, in the example shown in the drawing in the left direction. As described above, there is an order in attaching and detaching units. Therefore, even when it is desired to replace only the unit arranged on the back side in the take-out direction, the unit on the front side in the take-out direction, that is, the front side must be removed and placed outside.

  Therefore, in the present embodiment, the sheet feeding cassette 50 of the sheet feeding units 10 and 10 is configured to be able to be pulled out from the front side of the casing 2, and the transfer sheet is the front of the casing 2 (see FIG. It can be replenished while being pulled out to the front side. For this reason, the housing 2 is formed with an opening for drawing out the paper feed cassette 50 and is formed in the paper feed cassette 50 by mounting the paper feed cassette 50 in the paper feed units 10 and 10. A lid member covers the opening.

  The photosensitive drums 12Y, 12M, 12C, and 12K in the image forming unit 12 are configured as process units. Each process unit includes a charging unit and a developing unit in addition to the photosensitive drums 12Y, 12M, 12C, and 12K. In addition, a cleaner, a static eliminator, and the like are arranged, and each process unit is also attached / detached / replaced from the front side (front side of the drawing) of the housing 2. The toner cartridges 14Y, 14M, 14C, and 14K are also attached and detached and replaced from the front side (front side of the drawing) of the housing 2.

  On the other hand, the exposure unit 11 and the intermediate transfer unit 13 have an attachment / detachment direction different from the attachment / detachment described above. That is, the exposure unit 11 is attached to and detached from one side (left in FIG. 1) of the side of the housing 2 and can be pulled out for maintenance such as repair. The intermediate transfer unit 13 includes an exposure unit. 11 can be attached to and detached from the housing 2 on the right side in the opposite direction, and this can also be pulled out for maintenance.

  FIG. 2 shows a housing structure capable of realizing the above-described attachment / detachment configuration. In this figure, parts corresponding to those in FIG. This structure has a rectangular bottom plate (or bottom frame; hereinafter referred to as a base portion) 21, struts 22 to 25 erected vertically from the four corners of the base portion 21, and the struts 22 to 25. Two horizontal scanner support pieces 30 (from the front side of the device) mounted on the side plates 26 to 29 and the upper portions of the three long columns 22 to 24 positioned to support the bottom of the scanner device 5 positioned at the top. Only a visible portion is shown), a cantilevered scanner support piece 32a that protrudes horizontally from the upper end of the column 24 toward the short column 25, and an adjustment member 32b. In addition, each support | pillar 22-25, the scanner support piece 30, the cantilever support piece 32, and the adjustment member 32b comprise the structure main body, in other words, the housing | casing 2. FIG. The scanner device 5 is supported by two support pieces 30 and 32.

  FIG. 3 shows the structure of the exposure unit 11 of the apparatus of FIG. The exposure unit 11 includes an optical housing 51, a polygon scanner 52, a pair of soundproof glasses 53 (53a, 53b), an fθ lens 54 (54a, 54b, 54c, 54d), and a long lens (corresponding to the fθ lens 54). (Not shown), first mirror 56 (56a, 56b, 56c, 56d), second mirror 57 (57a, 57b, 57c, 57d), third mirror (not shown), dustproof glass 59 (59a, 59b, 59c, 59d), an upper cover 60, a lower cover 61, an optical path 63 (63a, 63b, 63c, 63d) for exposing the photosensitive drum 1 (1a, 1b, 1c, 1d), and a second cover 64. Have. That is, the exposure unit 11 includes not only the upper cover 60 but also the lower cover 61. The paper feed unit has a single-stage feed tray structure, but there is no problem even if it has a plurality of stages as in the previous example.

  The polygon scanner 52 is fastened to the optical housing 51, and a wall portion is formed on the outer periphery of the installation. However, a dust-proof glass 59 is installed in the scanning beam path reflected by the incident beam from the light source and the deflecting mirror so that desired scanning light can be deflected and scanned by a scanning lens or the like.

  The space formed by the upper cover 60 and the lower cover 61 of the exposure unit 11 blocks the inside of the exposure unit 11 from the outside, and is connected to the installation space of the deflector provided in the optical housing 51 to form one space. To do. Since this space is different from the space where other optical elements are installed, the high-temperature air current scattered by the deflection mirror does not directly hit the other optical elements, and the characteristics are not deteriorated.

  The space formed by the upper cover 60 and the lower cover 61 is unlikely to interfere with the layout of optical components installed in the exposure unit 11 as shown in the figure. For this reason, the degree of freedom in shape is relatively high in designing the shape. For example, a space can be secured in a direction perpendicular to the optical axis of the scanning lens or in the upper part of the scanning lens. It is possible to provide a space larger than the portion, and by doing so, it is possible to suppress the temperature rise of the deflector.

  FIG. 4 is a diagram schematically showing the above-described attachment / detachment configuration in the apparatus of FIG. In FIG. 4, the sheet feeding unit 10 is provided with only one stage of the sheet feeding cassette 51, and the configuration is different from the apparatus of FIG. 1. There is no difference, and there is no technical meaning to the single stage in FIG.

  The photosensitive drums 12Y, 12M, 12C, and 12BK are rotatably supported by a frame (not shown) of the housing 2, and are moved in the moving direction A1 of the intermediate transfer belt 41 that is an intermediate transfer member serving as a second image carrier. Along the left side of the figure. Further, the photosensitive drums 12Y, 12M, 12C, and 12BK are positioned below the outer peripheral surface of the intermediate transfer belt 41 that is an endless belt disposed almost at the center inside the housing 2, that is, on the image forming surface side. .

  The intermediate transfer belt 41 is wound around rollers 72, 73, 74 so as to be movable in the direction of the arrow A1 while being in sliding contact with the respective photosensitive drums 12Y, 12M, 12C, 12BK, and on the inner peripheral side thereof, the photosensitive drum 12Y. , 12M, 12C, 12BK, visible images, that is, toner images, formed on the primary transfer rollers 75Y, 75M, 75C, 75BK arranged to be positioned so as to be positioned can be transferred to the intermediate transfer belt 41 that moves in the direction of arrow A1. The images are superimposed and transferred to each other, and then collectively transferred onto a transfer sheet S as a recording medium.

  The intermediate transfer belt 41 is located at a lower position facing the photosensitive drums 12Y, 12M, 12C, and 12BK. The intermediate transfer belt 41 transfers toner images on the photosensitive drums 12Y, 12M, 12C, and 12BK to the intermediate transfer belt 41. Constitutes a primary transfer portion to be transferred.

  The toner image is transferred onto the intermediate transfer belt 41 in the process in which the intermediate transfer belt 41 moves in the direction of arrow A1, and the toner images formed on the photosensitive drums 12Y, 12M, 12C, and 12BK are the same as those on the intermediate transfer belt 41. By voltage application by primary transfer rollers 75Y, 75M, 75C, and 75BK disposed at positions facing each of the photosensitive drums 12Y, 12M, 12C, and 12BK with the intermediate transfer belt 41 interposed therebetween so as to be transferred in a superimposed manner. The timing is shifted from the upstream side to the downstream side in the direction of arrow A1.

  The intermediate transfer portion 13 including the intermediate transfer belt 41 is attached to the housing 2 by moving in the direction of arrow F1 in the figure, and is removed from the housing 2 by moving in the opposite direction.

  The intermediate transfer belt 41 has a multilayer structure in which, for example, the base layer is made of a material with less elongation, the surface of the base layer is covered with a material having good smoothness, and the coat layer is formed on the base layer. To do. Examples of the material of the base layer include a fluororesin, a PVDF sheet, and a polyimide resin. Examples of the material of the coating layer constituting the surface include a fluorine resin having good smoothness. Of course, other configurations may be used.

  The exposure unit 11 includes a light source, an optical system, and the like (not shown), and exposes the photosensitive drums 12Y, 12M, 12C, and 12BK of each image forming unit 12 based on the control of the host device. For this reason, an exposure unit 11 is provided below each image forming unit 12, and the exposure unit 11 has one deflector at the central portion inside, and the light beams from four light sources (not shown) are transmitted by one deflector. The four systems are distributed and deflected and scanned, and latent images are written on the four photosensitive drums 12Y, 12C, 12M, and 12Bk. For this purpose, four laser diode (LD) light sources prepared for each color, an optical system for collimating the laser beam emitted from the light source, a polygon mirror (rotating polygon mirror), and a polygon motor are used. A deflector (polygon scanner) 16 and an optical system composed of a scanning / imaging lens such as an fθ lens, a correction lens, a mirror, and the like arranged in the optical path of each light source. Since the specific configuration is well known, detailed illustration and description are omitted.

  Then, the laser beam emitted from the laser diode is deflected and scanned by the polygon scanner 10 according to the image information of each color, irradiated to the photosensitive drums 12Y, 12C, 12M, and 12Bk of each color, and the above-described latent image is written by the exposure. I do.

  The toner cartridge 14 provided at the uppermost part inside the housing 2 is provided so as to accommodate toner of the color corresponding to the reference numerals in the drawing in order to replenish the developing device for each image forming unit 12. is there. Filling the developing device of each color image forming unit 12 with toner is performed by supplying toner of each color by a predetermined amount via a conveyance path (not shown) by a known control device, control system, control software, or the like.

  The yellow, cyan, magenta, and black toners in the toner cartridge 3 are, for example, polymerized toners, and are replenished by a predetermined replenishment amount via a conveyance path (not shown).

  The printer also includes a cleaning device 76 that cleans the intermediate transfer belt 41 included in the transfer belt unit, an opening / closing portion 77 that supports the secondary transfer roller 91 and its cleaning blade 92 to open and close the housing 2, and a housing. Power supply means 78 and 79 constituting electrical contacts for supplying power from the body 2 side to the intermediate transfer unit 13 side including the intermediate transfer belt 41 and each component of the image forming apparatus including the intermediate transfer unit 13 On the other hand, it has the power supply device 80 which functions as a power supply.

  This printer also includes a drive device (not shown) that rotates and drives each of the photoconductive drums 12Y, 12M, 12C, and 12BK, a start switch (not shown) for instructing image formation start, and the like. The control panel includes a control panel (not shown) that controls the overall operation of the image forming apparatus.

  The intermediate transfer unit 13 includes primary transfer rollers 75Y, 75M, 75C, and 75BK as primary transfer bias rollers in addition to the intermediate transfer belt 41, and a drive roller 72 that is a drive member around which the intermediate transfer belt 41 is wound. A counter roller 74 as a tension roller, a tension roller 73 as a support roller for driving the intermediate transfer belt 41 together with the driving roller 72 and the cleaning roller 74, and an intermediate transfer belt 41 from the outside of the intermediate transfer belt 41. And a tension roller 81 for applying a predetermined tension to the intermediate transfer belt 41 together with the cleaning counter roller 74.

  The cleaning device 76 for the intermediate transfer belt 41 is disposed so as to face the intermediate transfer belt 41 at a position facing the cleaning facing roller 74. The cleaning device 76 includes a cleaning blade 86 disposed so as to contact the intermediate transfer belt 41 at a position facing the cleaning counter roller 74, and a case 87 in which the cleaning blade 86 is accommodated, and includes an intermediate transfer belt. The intermediate transfer belt 41 is cleaned by removing foreign matters such as residual toner on the roller 41 by scraping with a cleaning blade 86.

  The cleaning facing roller 74, the stretching roller 73, and the tension roller 81 are driven rollers that rotate with the intermediate transfer belt 41 that is rotationally driven by a driving roller 72 that is positioned at the rearmost side in the approaching direction into the housing 2. It has become. The primary transfer rollers 75Y, 75M, 75C, and 75BK press the intermediate transfer belt 41 from the back surface thereof toward the photosensitive drums 12Y, 12M, 12C, and 12BK to form primary transfer nips. The primary transfer nip is formed in a portion of the intermediate transfer belt 41 that extends between the cleaning facing roller 74 and the stretching roller 73. Therefore, the stretching roller 73 and the cleaning counter roller 74 exhibit a function of stabilizing the primary transfer nip. The tension roller 81 is in contact with the intermediate transfer belt 41 from the outside of the intermediate transfer belt 41 in the vicinity of the drive roller 72 and at a position below the drive roller 72, so that the intermediate transfer belt in the vertical direction as shown in the figure. It fulfills the function of reducing the space occupied by 41.

  In each primary transfer nip, a primary transfer electric field is formed between the photosensitive drums 12Y, 12M, 12C, and 12BK and the primary transfer rollers 75Y, 75M, 75C, and 75BK due to the influence of the primary transfer bias. The toner images of the respective colors formed on the photosensitive drums 12Y, 12M, 12C, and 12BK are primarily transferred onto the intermediate transfer belt 41 due to the influence of the primary transfer electric field and nip pressure.

  The drive roller 72 faces the secondary transfer roller 91 with the intermediate transfer belt 41 interposed therebetween, and constitutes a secondary transfer unit. The cleaning counter roller 74 functions as a pressure member that applies a predetermined tension suitable for transfer to the intermediate transfer belt 41 together with the tension roller 81.

  The paper feeding unit 10 accommodates a plurality of transfer papers S in a stack of transfer papers in a paper feeding cassette, and is disposed below the housing 2 and below the exposure unit 11. That is, a paper bank is formed at the bottom of the housing 2 by the paper feeding unit 10.

  The sheet feeding unit 10 separates only one of the sheet feeding roller 82 pressed against the upper surface of the uppermost transfer sheet S in the sheet feeding cassette and the transfer sheet S fed by the sheet feeding roller 82. Further, the sheet feeding roller 82 is driven to rotate counterclockwise in the drawing at a predetermined timing, and the uppermost transfer sheet S is fed toward the registration roller pair 88. Is done. The transfer paper S sent out from the paper supply unit 10 reaches the registration roller pair 88 through the paper supply path 90 and is sandwiched between the rollers of the registration roller pair 88.

  The secondary transfer roller 91 serving as the secondary transfer device of this example is provided in the opening / closing portion 77 and is disposed so as to face the drive roller 72 and sandwich the intermediate transfer belt 41 when the opening / closing portion 77 is closed. It is. The secondary transfer roller 91 also has a sheet conveying function for conveying the transfer sheet S after the toner image has been transferred to the fixing device 8 in the direction of arrow E1 in the figure. As the secondary transfer device, a configuration using a belt-like member may be adopted, or a non-contact charger may be used. The cleaning device 92 in the illustrated example is a blade-like member that contacts the secondary transfer roller 91 to remove foreign matters such as paper dust and toner adhering to the secondary transfer roller 91, and the secondary transfer roller. 91 is cleaned.

  The opening / closing part 77 has a shaft 93 that serves as a center of rotation when rotating with respect to the housing 2, and can be opened and closed with respect to the housing 2 together with the secondary transfer roller 91 and the cleaning device 92. As shown in FIG. 4, when the opening / closing part 77 is opened with respect to the housing 2, the transfer belt unit can be mounted at a fixed position in the housing 2. Although the detailed illustration and description are omitted, the transfer belt unit can be detached from the housing 2 for maintenance or the like by a known configuration. That is, when the transfer belt unit is taken out from the housing 2, the opening / closing portion 77 is opened with respect to the housing 2 and the inside of the housing 2 is opened.

  The photosensitive drums 12Y, 12M, 12C, 12BK and the peripheral devices have the same configuration. In other words, around the photosensitive drums 12Y, 12M, 12C, and 12BK, the intermediate transfer belt 41 and the like are mounted on the housing 2 along the clockwise direction in the drawing (the rotation direction indicated by arrows B1 to B4). A primary transfer roller 75, a cleaning blade 102 as a cleaning unit, a neutralization unit 103 as a neutralization unit, a charging unit 104 as a charging unit that performs AC charging, and a development unit 105 as a development unit that performs development using a two-component developer. It becomes the composition which has.

  In FIG. 4, illustration of the attachment / detachment of the exposure unit 11 is omitted, and only the arrows are shown.

  As shown in FIG. 5 and as described above, the intermediate transfer unit 13 according to this embodiment wraps the intermediate transfer belt 41 around the driving roller 72, the stretching roller 73, and the cleaning counter roller 74, and the tension roller 81 counters the cleaning. A predetermined tension is applied to the intermediate transfer belt 41 together with the roller 74. In this embodiment, the height dimension H2 on the side that enters the inside of the housing 2 (left side in FIG. 5) is set to the rear side in the approach direction (right side in FIG. 2) that is the opposite side. It is configured so that it can be easily taken out from the housing 2 even from the side where the height dimension is smaller than the height dimension H1 of the part. That is, since the intermediate transfer unit 13 is taken out from the housing 2 from the side with the large height dimension and is inserted into the housing 2 from the side with the small height size, the space necessary for attaching and detaching the intermediate transfer unit 13 in the housing 2 Can be reduced. Further, the attaching / detaching operation of the intermediate transfer unit 13 can be performed smoothly.

  FIG. 6 is a conceptual diagram showing the positional relationship between the housing 2 and the intermediate transfer unit 13 from the direction of arrow A shown in FIG. The intermediate transfer unit 13 can be attached / detached by sliding in the front direction along a front guide 37 provided on the front plate 34 of the housing 2 and a rear guide 36 provided on the rear plate 33. Further, the portion of the intermediate transfer portion 13 other than the portion to be attached and detached is configured to maintain strength by the stay.

  In addition, the exposure unit 11 is attached and detached using the housing intermediate base 35 disposed on the paper feeding units 10 and 10 as a guide. That is, the exposure unit 11 includes a detachable portion 11a that can be attached to and detached from the housing 2, and a fixed portion 11b that is attached to the housing 2 that cannot be attached and detached. Remove from the side (left side in FIG. 1). The fixed portion 11b includes a stay 31 and another stay (not shown), and contributes to maintaining the strength of the housing 2.

  That is, in the present embodiment, with such a configuration, the paper feed roller 32 can be lowered to the vicinity of the lowermost portion of the arrangement position of the removable portion 11 a of the exposure unit 11. Therefore, the overall height of the color printer 1 can be reduced by the arrangement dimension H3 (FIG. 1) of the paper feed roller 32.

  Further, in this embodiment, the exposure unit 11 and the intermediate transfer unit 13 are attached and detached from the opposite side of the housing 2 so that the exposure unit 11 and the intermediate transfer unit 13 can be attached and detached from the same side. It is possible to eliminate the necessity of forming a large opening on one side of the housing 2, and it is only necessary to provide the minimum necessary openings on the two opposite surfaces of the housing 2, so that the length of the beam member required for forming the opening The mechanical strength of the housing 2 can be increased accordingly.

  FIG. 7 is a conceptual cross-sectional view showing a configuration of a modified example of the cleaning device that can be employed in the intermediate transfer unit 13 having the above-described configuration. The cleaning device 20 includes a cleaning unit 20a and a waste toner tank 20b. The cleaning unit 20a includes a cleaning blade 20c, removes residual toner on the intermediate transfer belt 41, and discharges it into the waste toner tank 20b. Although illustration of a detailed structure is omitted, the waste toner tank 20b is configured as a vertically long cylinder having a height dimension larger than the width direction dimension, and the intermediate transfer unit 13 and the cleaning unit 20a, and the cleaning unit 20a and the waste toner tank. It can be separated from 20b. Therefore, for example, when the intermediate transfer unit 13 is pulled out, the cleaning unit 20 a is also pulled out, and the waste toner tank 20 b can be left in the housing 2. In addition, after the exposure unit 11 is pulled out, a maintenance operation or the like is performed by putting a hand into the housing 2 from the opening portion from which the exposure unit 11 is pulled out, or the internal waste toner is processed by taking out the exposure unit 11. Can do.

  Note that the illustrated waste toner tank 20b is formed in a cylindrical shape that is long in the vertical direction. If the waste toner tank 20b is extended downward in this way, the capacity of the waste toner tank 20b can be increased, and the waste toner can be accumulated inside the tank and compressed by its own weight, thereby reducing the volume. it can. In some cases, after the exposure unit 11 is taken out, only the waste toner tank 20b can be easily taken out from the housing 2.

  FIG. 8 is a perspective view showing a specific configuration example of the intermediate transfer unit 13 as described above. The illustrated intermediate transfer unit 13 is disposed on both sides of the intermediate transfer belt 41 and is disposed between the frames 83 and 83 serving as guide members when the transfer belt unit is attached to and detached from the housing 2. And a connecting member 84 for connecting both the frames 83. The connecting member 84 is provided with a power-supplied portion (described as power supply means in the description of FIG. 4) 78 that constitutes a power supply means that can receive power from the housing 2 side when the intermediate transfer portion 13 is attached to the housing 2. Have. In FIG. 8, illustrations of a driving roller, a cleaning facing roller, a stretching roller, a tension roller, and the like are omitted.

  As described above, the intermediate transfer unit 13 is attached to the housing 2 by moving in the direction of the arrow F1 in the figure. The frame 67 functions as a slider when sliding in the direction of the arrow F1 by a guide rail (not shown) provided on the housing 2 when the intermediate transfer unit 13 is mounted on the housing 2.

  The power-supplied part 78 includes power-supplied bodies 78 a to 78 e integrated with the intermediate transfer part 13, and when the transfer belt unit is mounted at a predetermined position in the housing 2, the power-feeding part 79 contacts the power-supplied bodies 78 a to 78 e. Are electrically connected to the power-supplied bodies 78a to 78e to supply power to the intermediate transfer portion 13. Note that the power-supplied portion 78 is positioned above the photosensitive drums 12 </ b> Y, 12 </ b> M, 12 </ b> C, and 12 </ b> BK across the intermediate transfer belt 41 and at a location near the outside of the housing 2.

  As described above, according to the present invention, a consumable with a high replacement frequency is operated on the front side of the apparatus, and a module with a low replacement frequency or a lifespan equivalent to the apparatus is operated on the side of the apparatus. Therefore, it is possible to prevent an erroneous operation by the user.

  In addition, since the exposure unit and the intermediate transfer unit are taken out from the left and right sides, interference between each unit can be prevented, the overall height of the color printer can be reduced, and the casing required for operation Therefore, it is not necessary to form a large opening in the housing, and the strength of the housing can be improved.

  In addition, according to the present invention, the height dimension of each part is changed in the width direction without impairing the function thereof, and the height dimension of the entire image forming apparatus is offset by the other parts overlapping vertically. Can be made small.

  In addition, according to the present invention, since each part is attached to the housing from the side where the thickness dimension is small, and is removed from the case from the side where the thickness dimension is large, the mounting space to today can be reduced. The attachment / detachment operation can be made smooth.

  Further, according to the present invention, since the cleaning device is arranged at the side portion of the intermediate transfer portion, it is not necessary to arrange another portion in the vertical direction of the intermediate transfer portion, and the height dimension of the entire image forming apparatus is reduced. Can be reduced. Furthermore, it is not necessary to pull out the entire intermediate transfer device out of the cleaning device having a shorter service life than the intermediate transfer unit and when replacing the parts, and the operation can be easily performed.

  According to the present invention, since the waste toner tank has a vertically long cylindrical shape, the waste toner is compressed by its own weight, so that the volume of the waste toner can be reduced, and the waste toner tank is moved to the position of the exposure unit. The tank capacity can be increased by stretching. Furthermore, since the waste toner tank and the cleaning device can be separated, they can be replaced as a unit at intervals suitable for their respective lifetimes.

  According to the present invention, since the waste toner tank can be repaired and replaced from the opening for the exposure part, there is no need to provide an opening for the waste toner tank, and the strength of the housing is not reduced. .

1 is a schematic cross-sectional view showing a color printer as an embodiment of an image forming apparatus according to the present invention. The perspective view which shows an example of the housing structure of the apparatus of FIG. Sectional drawing which shows the structure of the exposure part of the apparatus of FIG. Schematic diagram showing the attachment / detachment structure of the exposure unit and the intermediate transfer unit in the apparatus of FIG. Schematic diagram showing an intermediate transfer unit used in the apparatus of FIG. Side view from the direction of arrow A in FIG. Conceptual sectional view showing the configuration of a modified example of the cleaning device that can be employed in the intermediate transfer unit The perspective view which shows the specific structural example of an intermediate transfer part. Cross section of a conventional color printer for comparison

Explanation of symbols

1: Color printer 2: Housing 5: Document reading unit 8: Fixing device 10: Paper feeding unit 11: Exposure unit 11a: Removable portion 11b: Fixed portion 12: Image forming units 12Y to 12K: Image carrier (photosensitive member) drum)
13: Intermediate transfer unit 14 (14Y to 14K): Toner cartridge 16: Rotating deflector (polygon scanner)
17: paper discharge unit 20: cleaning device 20a: cleaning unit 20b: waste toner tank 20c: cleaning blade 21: base portion 22-25 of housing: same column 26-29: same side plate 30: scanner support piece 31: stay 32 : Feed roller 32a: Scanner support piece 32b: Adjustment member 33: Rear plate 34 of the case: Front plate 35 of the case: Case intermediate base 36: Rear guide 37: Front guide 41: Intermediate transfer belt 42: Drive roller 43 to 45: Turning roller 50: Paper feed cassette 51: Optical housing 52: Polygon scanner 53 (53a, 53b): A pair of soundproof glass 54 (54a to 54d): fθ lens 56 (56a to 56d): First mirror 57 (57a to 57d): second mirror 59 (59a to 59d): dustproof glass 60: upper cover 61: lower cover 63 (6 a to 63d): optical path for exposure of photosensitive drum 64: second cover 67: frame 72: drive roller 73: stretching roller 74: cleaning counter roller 75Y to 75BK: primary transfer roller 76: cleaning device 77: Opening / closing part 78: Power-supplied part (power feeding means)
78a to 78e: Power-supplied body 79: Power supply means 80: Power supply device 81: Tension roller 82: Paper feed roller 83: Frame 84: Connecting member 86: Cleaning blade 87: Case 88: Registration roller pair 90: Paper feed path 91: Secondary transfer roller 92: cleaning blade (cleaning device)
93: shaft 102: cleaning blade 103: neutralizing device 104: charging device 105: developing device S: transfer paper F1: mounting direction H1, H2 of the intermediate transfer unit H3: height of the intermediate transfer unit H3: layout size of the feeding roller

Claims (20)

An image forming apparatus,
An image forming unit having an image carrier in the housing, a paper feeding unit for supplying transfer paper to the image forming unit, and an exposure unit for exposing the image carrier of the image forming unit to form a latent image A developing device for developing the latent image formed on the image carrier with toner, an intermediate transfer unit for intermediate transfer of a toner image on the image carrier developed by the developing device, and a toner unit for supplying toner to the developing device With
From the front side opening of the housing,
Transfer paper can be supplied to the paper feed unit,
The imaging unit can be replaced
The toner supply unit can replace a toner cartridge,
From one side opening of the left side and the right side of the housing,
The intermediate transfer part can be attached and detached,
From the other direction side opening of the left side and the right side of the housing,
An image forming apparatus to which the exposure unit can be attached and detached. The image forming apparatus according to claim 1.
An image forming apparatus in which the intermediate transfer portion is smaller than the height dimension on the front side in the approach direction into the housing and smaller than the height dimension on the rear side in the approach direction. The image forming apparatus according to claim 2.
The intermediate transfer part is configured by winding an endless intermediate transfer belt around a plurality of rollers,
The intermediate transfer belt wound around the plurality of rollers is given a predetermined tension by applying one tension roller from the outside at a position on the rear 17 side in the approach direction into the housing, and
An image forming apparatus in which the one tension roller is positioned at a position lower in the height direction than the roller positioned closest to the rearmost side in the entry direction into the housing. The image forming apparatus according to claim 3.
A cleaning device for collecting waste toner removed from the intermediate transfer belt by the intermediate transfer unit;
The cleaning device is disposed on the front side in the direction in which the intermediate transfer portion enters the housing, and the cleaning device can be operated from the side from which the exposure portion is taken out after the exposure portion is taken out. Image forming apparatus. The image forming apparatus according to claim 4.
The cleaning device includes a waste toner tank for storing waste toner collected from the intermediate transfer belt;
An image forming apparatus in which the waste toner tank is disposed below the cleaning device and has a vertically long cylindrical shape. The image forming apparatus according to claim 5.
An image forming apparatus in which the waste toner tank can be separated from the cleaning device. The image forming apparatus according to claim 6.
An image forming apparatus in which the waste toner tank is extended to the vicinity of the upper part of the exposure unit to increase the volume. The image forming apparatus according to claim 1.
A cleaning device for collecting waste toner removed from the intermediate transfer belt by the intermediate transfer unit;
The cleaning device is disposed on the front side in the direction in which the intermediate transfer portion enters the housing, and the cleaning device can be operated from the side from which the exposure portion is taken out after the exposure portion is taken out. Image forming apparatus. The image forming apparatus according to claim 8.
The cleaning device includes a waste toner tank for storing waste toner collected from the intermediate transfer belt;
An image forming apparatus in which the waste toner tank is disposed below the cleaning device and has a vertically long cylindrical shape. The image forming apparatus according to claim 9.
An image forming apparatus in which the waste toner tank can be separated from the cleaning device. The image forming apparatus according to claim 10.
An image forming apparatus in which the exposure unit includes a detachable part that can be attached to and detached from the casing, and a fixed part to the casing that cannot be removed from the casing. The image forming apparatus according to claim 11.
An image forming apparatus in which an arrangement position of a sheet feeding roller provided in the sheet feeding unit is lowered to a position near a lowermost part of an arrangement position of a removable part of the exposure unit. The image forming apparatus according to claim 1.
An image forming apparatus in which the exposure unit includes a detachable part that can be attached to and detached from the casing, and a fixed part to the casing that cannot be removed from the casing. The image forming apparatus according to claim 13.
An image forming apparatus in which an arrangement position of a sheet feeding roller provided in the sheet feeding unit is lowered to a position near a lowermost part of an arrangement position of a removable part of the exposure unit. The image forming apparatus according to claim 14.
An image forming apparatus in which the intermediate transfer portion is smaller than the height dimension on the front side in the approach direction into the housing and smaller than the height dimension on the rear side in the approach direction. The image forming apparatus according to claim 15.
The intermediate transfer part is configured by winding an endless intermediate transfer belt around a plurality of rollers,
The intermediate transfer belt wound around the plurality of rollers is given a predetermined tension by applying one tension roller from the outside at a rear portion in the approach direction into the housing, and
An image forming apparatus in which the one tension roller is positioned at a position lower in the height direction than the roller positioned closest to the rearmost side in the entry direction into the housing. The image forming apparatus according to claim 16.
A cleaning device for collecting waste toner removed from the intermediate transfer belt by the intermediate transfer unit;
The cleaning device is disposed on the front side in the direction in which the intermediate transfer portion enters the housing, and the cleaning device can be operated from the side from which the exposure portion is taken out after the exposure portion is taken out. Image forming apparatus. The image forming apparatus according to claim 17.
The cleaning device includes a waste toner tank for storing waste toner collected from the intermediate transfer belt;
An image forming apparatus in which the waste toner tank is disposed below the cleaning device and has a vertically long cylindrical shape. The image forming apparatus according to claim 18.
An image forming apparatus in which the waste toner tank can be separated from the cleaning device. The image forming apparatus according to claim 19.
An image forming apparatus in which the waste toner tank is extended to the vicinity of the upper part of the exposure unit to increase the volume.