Image forming device

Abstract

To facilitate replacement of a unit to prevent damage to the unit and prevent toner cloud from staying between the units.SOLUTION: An image forming apparatus comprises: a first guide that is provided in an apparatus housing and hangs and holds a first unit having an image holding body movably in insertion and withdrawal directions; a second guide that is provided in the apparatus housing and hangs and holds a second unit having an image holding body movably in insertion and withdrawal directions; and a pedestal that is arranged on a near side in the insertion and withdrawal directions with respect to the first guide and the second guide, supports the first unit and the second unit being inserted into the apparatus housing from below in the gravity direction, and is not in contact with the first unit and the second unit located in the apparatus housing.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus. [Background technology]

[0002] In an image forming device having a plurality of cartridges which are removably inserted into a predetermined position in the main body of the device in a predetermined order and along a predetermined insertion path formed by a guide, a cartridge which is inserted before the other cartridges is provided with a guide portion which guides the insertion of the other cartridge, which is inserted after it, into its predetermined position in the main body of the device when the cartridge is inserted into its predetermined position in the main body of the device, and a cartridge which is inserted after the other cartridges is provided with a guided portion which is guided for insertion into its predetermined position in the main body of the device by the guide portion of the other cartridge which was inserted into its predetermined position in the main body of the device before it, and the guide portion is a surface which guides the other cartridge so that the other cartridge is inserted into a guide provided in the main body of the device itself which guides the insertion of the other cartridge, and the guide portion cooperates with a guide in the main body of the device (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3536577 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention facilitates replacement of units, suppresses damage to the units, and suppresses accumulation of toner cloud between units. [Means for solving the problem]

[0005] In order to solve the above problem, the image forming apparatus according to claim 1 comprises: a first guide provided in a device housing for suspending and holding a first unit having an image carrier so as to be movable in an insertion / removal direction; a second guide provided in the device housing and configured to suspend and hold a second unit having a developer holder so as to be movable in an insertion / removal direction; On the front side in the insertion / removal direction with respect to the first guide and the second guide so that it does not protrude from the device housing. To The device housing is provided integrally with and a base that supports the first unit and the second unit from below in the gravity direction during insertion into the device housing and does not come into contact with the first unit and the second unit positioned in the device housing. It is characterized by:

[0006] The invention described in claim 2 is the image forming apparatus described in claim 1, a third guide is provided on the base, the third guide being fitted with the second unit and restricting movement of the first unit in a direction intersecting with the insertion / removal direction; It is characterized by:

[0007] The invention described in claim 3 is the image forming apparatus described in claim 1 or 2, The first unit has a hook shape that engages with the first guide. It is characterized by:

[0008] The invention described in claim 4 is the image forming apparatus described in claim 1 or 2, The second unit has a hook shape that engages with the second guide. It is characterized by:

[0009] The invention described in claim 5 is the image forming apparatus described in any one of claims 1 to 4, The second unit has a fourth guide that guides the insertion and removal of the first unit. It is characterized by:

[0010] The invention described in claim 6 is the image forming apparatus described in claim 5, The first unit has a fifth guide that guides the insertion and removal of the first unit to the fourth guide. It is characterized by:

[0011] The invention described in claim 7 is the image forming apparatus described in claim 6, the fifth guide has a cross-sectional shape of a substantially triangular shape having an apex at an upper position, and is shaped to divide air flows accompanying rotation of the image carrier and the developer carrier; It is characterized by:

[0012] The invention described in claim 8 is the image forming apparatus described in claim 7, the triangular shape is composed of inclined surfaces having an inclination angle exceeding the angle of repose of the toner; It is characterized by:

[0013] The invention described in claim 9 is the image forming apparatus described in claim 7 or 8, The triangular shape has an inclined surface having a predetermined gap with respect to the curvature of the image carrier as one side. It is characterized by:

[0014] The present invention as set forth in claim 10 is the image forming apparatus as set forth in any one of claims 6 to 9, The fifth guide is a tie bar connecting both ends of the first unit in the insertion / removal direction. It is characterized by:

[0015] The invention described in claim 11 is the image forming apparatus described in any one of claims 1 to 10, the image carrier is a photoconductor drum, The first unit is a drum unit. It is characterized by: Effect of the Invention

[0016] According to the invention recited in claim 1, replacement of the unit is facilitated and damage to the unit is suppressed.

[0017] According to the invention recited in claim 2, the posture of the second unit when it is inserted into the device housing can be stabilized.

[0018] According to the invention as recited in claim 3, the first unit can be easily inserted into and removed from the device housing.

[0019] According to the invention as recited in claim 4, the second unit can be easily inserted into and removed from the device housing.

[0020] According to the invention as recited in claims 5 and 6, the second unit, which has been inserted first into the device housing, can stabilize the attitude of the first unit, which is to be inserted into the device housing later.

[0021] According to the invention as set forth in claims 7, 8 and 9, it is possible to suppress the accumulation of the toner cloud between the first unit and the second unit.

[0022] According to the invention as recited in claim 10, the space required for the first unit can be reduced.

[0023] According to the eleventh aspect of the present invention, damage to the photosensitive drum can be suppressed. [Brief description of the drawings]

[0024] [Figure 1] 1 is a schematic cross-sectional view illustrating an example of a schematic configuration of an image forming apparatus. [Diagram 2] FIG. 2 is a schematic cross-sectional view illustrating a unit configuration in the image forming apparatus. [Diagram 3] 1A is a schematic plan view showing the arrangement of a first guide, a second guide and a base of an apparatus housing, and FIG. [Figure 4] FIG. 2 is a perspective view illustrating how the developing device is attached to the device housing. [Diagram 5] FIG. 2 is a perspective view illustrating how a photosensitive unit is attached to a housing of the apparatus. [Figure 6] FIG. 4 is a front sectional view illustrating the installation of the photosensitive unit in a state in which the developing device has been previously installed. [Figure 7] FIG. 13A is a diagram for explaining the air flow caused by the rotation of the developing roll and the photosensitive drum, and FIG. 13B is a diagram for explaining the division of the air flow by the fifth guide. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] The present invention will be described in more detail below with reference to the drawings, showing embodiments and specific examples, but the present invention is not limited to these embodiments and specific examples. In addition, in the following explanation using the drawings, it should be noted that the drawings are schematic and the ratios of the dimensions, etc. may differ from the actual ones, and in order to make it easier to understand, illustrations other than those of parts necessary for the explanation have been omitted as appropriate. For ease of understanding in the following description, in the drawings, the front-rear direction is defined as the X-axis direction, the left-right direction as the Y-axis direction, and the up-down direction as the Z-axis direction.

[0026] (1) Overall Configuration and Operation of Image Forming Apparatus (1.1) Overall configuration of image forming apparatus FIG. 1 is a schematic cross-sectional view showing an example of a schematic configuration of an image forming apparatus 1 according to the present embodiment. The image forming apparatus 1 is configured to include an image forming section 10, a paper feeding device 20 attached to one end of the image forming section 10, a paper discharge section 30 provided at the other end of the image forming section 10 and from which printed paper is discharged, and an image processing section 40 (not shown) that generates image information from printing information transmitted from a higher-level device.

[0027] The image forming unit 10 is configured with a system control device 11 (not shown), an exposure device 12, a photosensitive unit 13, a developing device 14, a transfer device 15, paper transport devices 16a, 16b, 16c, a fixing device 17, and a drive device 18 (not shown), and forms the image information received from the image processing unit 40 as a toner image on paper fed from the paper feed device 20.

[0028] The paper feed device 20 supplies paper to the image forming unit 10. That is, the paper feed device 20 is provided with a plurality of paper stacking units that store paper of different types (e.g., materials, thicknesses, paper sizes, and paper grains), and is configured to supply paper fed from any one of the plurality of paper stacking units to the image forming unit 10.

[0029] The paper discharge section 30 discharges the paper on which an image has been output by the image forming section 10. To this end, the paper discharge section 30 is provided with a paper discharge storage section into which the paper after the image has been output is discharged. The paper discharge section 30 may also have a function of performing post-processing such as cutting and stapling on the paper stack output from the image forming section 10.

[0030] (1.2) Configuration and operation of the image forming unit In the image forming apparatus 1 configured as above, paper is fed from a paper stacking unit of the paper feeder 20 designated for each sheet to be printed in a print job to the image forming unit 10 in accordance with the timing of image formation.

[0031] Photoconductor unit 13, an example of a first unit, includes photoconductor drums 31 as image carriers that are arranged in parallel and rotated below exposure device 12. Along the rotation direction of photoconductor drum 31, charging roll 32, exposure device 12, developing device 14, primary transfer roll 52, and cleaning blade 34 are arranged.

[0032] The developing device 14, which is an example of a second unit, has a developing housing 41 that contains a developer therein. In the developing housing 41, a developing roll 42 is disposed opposite the photoconductor drum 31. The developing devices 14 are configured in substantially the same manner except for the developer contained in a developing housing 41, and form toner images of yellow (Y), magenta (M), cyan (C), and black (K), respectively.

[0033] Above the developing device 14, there are disposed replaceable toner cartridges T that contain developer (toner containing carrier), and a developer supplying device 60 that supplies developer from each toner cartridge T to the developing device 14. In this embodiment, yellow (Y), magenta (M), and cyan (C) toner cartridges Ty, Tm, and Tc, and two black (K) toner cartridges Tk are detachable.

[0034] The surface of the rotating photoconductor drum 31 is charged by the charging roll 32, and an electrostatic latent image is formed on it by latent image forming light emitted from the exposure device 12. The electrostatic latent image formed on the photoconductor drum 31 is developed into a toner image by the developing roll 42.

[0035] The transfer device 15 is configured to include an intermediate transfer belt 51 onto which the toner images of each color formed on the photosensitive drum 31 of each photosensitive unit 13 are multiple-transferred, a primary transfer roll 52 which sequentially transfers (primary transfer) the toner images of each color formed on each photosensitive unit 13 onto the intermediate transfer belt 51, and a secondary transfer roll 53 which collectively transfers (secondary transfer) the toner images of each color transferred in a superimposed state onto the intermediate transfer belt 51 onto a recording medium, i.e., paper.

[0036] The color toner images formed on the photosensitive drum 31 of each photosensitive unit 13 are electrostatically transferred (primary transfer) sequentially onto the intermediate transfer belt 51 by a primary transfer roll 52 to which a predetermined transfer voltage is applied from a power supply device (not shown) controlled by the system control device 11, and a superimposed toner image in which the color toners are superimposed is formed.

[0037] The superimposed toner image on the intermediate transfer belt 51 is transported to a secondary transfer portion TR where the secondary transfer roll 53 is arranged in pressure contact with the backup roll 65 via the intermediate transfer belt 51 as the intermediate transfer belt 51 moves. When the superimposed toner image is transported to the secondary transfer portion TR, a sheet is supplied to the secondary transfer portion TR from the sheet feeder 20 in time with the transport. A predetermined secondary transfer voltage is applied from a power supply device controlled by the system control device 11 to a backup roll 65 that faces the secondary transfer roll 53 across the intermediate transfer belt 51, and the multiple toner images on the intermediate transfer belt 51 are collectively transferred onto the sheet.

[0038] Residual toner on the surface of the photoconductor drum 31 is removed by a cleaning blade 34 and collected in a waste toner container (not shown). The surface of the photoconductor drum 31 is recharged by a charging roll 32.

[0039] The fixing device 17 has an endless fixing belt 17a that rotates in one direction, and a pressure roll 17b that contacts the peripheral surface of the fixing belt 17a and rotates in one direction, and a nip portion (fixing area) is formed by the pressure contact area between the fixing belt 17a and the pressure roll 17b. The paper onto which the toner image has been transferred in the transfer device 15 is transported via the paper transport device 16a to the fixing device 17 without the toner image being fixed thereon. The toner image on the paper transported to the fixing device 17 is fixed thereon by the action of pressure and heat by a pair of a fixing belt 17a and a pressure roll 17b.

[0040] The paper on which the fixing has been completed is sent to the paper discharge section 30 via the paper transport device 16b. When images are to be output on both sides of the paper, the paper is turned over by the paper transport device 16c and sent again to the secondary transfer unit TR in the image forming unit 10. Then, after the toner image is transferred and the transferred image is fixed, the paper is sent to the paper discharge unit 30. The paper sent to the paper discharge unit 30 is subjected to post-processing such as cutting and stapling as necessary, and then discharged to the paper discharge storage unit.

[0041] (2) Unit configuration and installation operation of image forming device Fig. 2 is a schematic cross-sectional view for explaining the unit configuration in the image forming apparatus 1, Fig. 3(a) is a schematic plan view showing the arrangement of the first guide 110, second guides 120, 121 and base 130 of the apparatus housing 100, and (b) is a schematic vertical cross-sectional view. Below, the configurations and installation operations of the photoconductor unit 13, the developing device 14 and the apparatus housing 100 will be explained with reference to the drawings.

[0042] As shown in FIG. 2, in the image forming apparatus 1, a plurality of photoconductor units 13 and developing devices 14 are detachably housed in an apparatus housing 100 and arranged therein.

[0043] (2.1) Photoconductor unit As shown in FIG. 2, in the photosensitive unit 13, the photosensitive drum 31 is supported in a unit housing 35 so as to be freely rotatable (indicated by arrow A in FIG. 2), and within the unit housing 35 are arranged a charging roll 32, a cleaning roll 33, a cleaning blade 34, and a transport auger 36 that transports the toner removed by the cleaning blade 34 to a waste toner collection container (not shown).

[0044] A first hook 37, which is an example of a hook shape that engages with a first guide 110 provided in the device housing 100 described later, is integrally provided in the unit housing 35. The first hook 37 is formed to protrude upward (in the Z direction) at the topmost position of the photosensitive unit 13 and extend from the front side to the back side of the photosensitive unit 13, and guides the insertion and removal of the photosensitive unit 13 into and from the device housing 100 while being suspended from the first guide 110 provided in the device housing 100.

[0045] Further, the unit housing 35 is provided with a fifth guide 38 that extends from the front side to the rear side of the photosensitive unit 13 below the photosensitive unit 13 with a gap between it and the photosensitive drum 31. The fifth guide 38 is guided by the developing device 14 that has been inserted into the device housing 100 first, and stabilizes the position of the photosensitive unit 13 that is suspended by the first guide 110 and inserted or removed.

[0046] (2.2) Developing device 2, in the developing device 14, a developing roll 42 is rotatably supported in a developing housing 41, and an agitating auger 43A and a supply auger 43B are disposed in the developing housing 41. The developer is filled around the agitating auger 43A and the supply auger 43B in the developing housing 41, and is closed by a cover member 44.

[0047] The developing roll 42 includes a cylindrical developing sleeve 42A rotatably supported relative to the developing housing 41, and a magnet 42B serving as a cylindrical magnetic member disposed in the internal space of the developing sleeve 42A and fixed to the developing housing 41. The developing sleeve 42A is configured such that the developer is held on its outer peripheral surface by the magnetic force of the magnet 42B, and the developer is transported and supplied to the electrostatic latent image on the photosensitive drum 31 by the rotation of the developing sleeve 42A (indicated by arrow B in FIG. 2).

[0048] The developing housing 41 is provided with second hooks 46, 47 as an example of a hook shape that engages with second guides 120, 121 provided in the device housing 100. The second hook 46 is formed on the back side in the insertion / removal direction of the developing housing 41, and guides the insertion / removal of the developing device 14 into the device housing 100 while being hung from the second guide 120 provided in the device housing 100. The second hook 47 is formed extending from the front side to the back side in the insertion / removal direction of the developing housing 41, and guides the insertion / removal of the developing device 14 into the device housing 100 while being hung from the second guide 121 provided in the device housing 100.

[0049] A guide groove 48 is formed on the underside of the developing device 14 to fit into a third guide 131 provided on a base 130 of the device housing 100, which will be described later, and regulates left and right movement of the developing device 14 when the developing device 14 starts to be inserted into the device housing 100. In addition, a fourth guide 49 is provided on the tip side of the guide groove 48 facing the photosensitive unit 13, which receives a fifth guide 38 provided on the photosensitive unit 13 to be inserted later and guides the insertion and removal of the photosensitive unit 13.

[0050] (2.3) Equipment housing The device housing 100 has an opening 101a on the front side, which is the front surface of the image forming apparatus 1, so that the photoconductor unit 13 and the developing device 14 can be inserted into and removed from the device housing 100. As shown in FIG. 3, the device housing 100 is provided with a first guide 110 and second guides 120 and 121 corresponding to the photoconductor unit 13 and the developing device 14 that are inserted and removed, respectively.

[0051] As shown in Fig. 3(a), the first guide 110 is provided extending from the front side to the back side (Y direction) of the device housing 100. As shown in Fig. 3(b), the first guide 110 has receiving portions 111 and 112 facing each other and a groove portion 113 formed in the center. The first guide 110 receives the first hook 37 provided on the photoconductor unit 13, which is inserted from the front side, in the groove portion 113 and holds it by hanging it from the receiving portions 111 and 112.

[0052] 3(a), the second guides 120 and 121 are provided extending from the front side to the rear side (Y direction) of the device housing 100. The second guide 120 engages with a second hook 46 provided on the developing device 14 to suspend and hold the developing roll 42 side of the developing device 14 inserted from the front side of the device housing 100. The second guide 121 engages with a second hook 47 provided on the developing device 14 to suspend and hold the stirring auger 43A side of the developing device 14 inserted from the front side of the device housing 100. In this embodiment, of the photosensitive unit 13 and developing device 14 which are detachable from the device housing 100, the developing device 14 is adapted to be attached first, and the developing device 14 is suspended from second guides 120, 121 which are spaced apart from each other and provided in the device housing 100 in a direction intersecting the insertion / removal direction, and is inserted and removed while maintaining a horizontal position.

[0053] As shown in FIG. 3, the photoconductor unit 110 is supported by a first guide 110 and second guides 120 and 121 of the device housing 100. 13A pedestal 130 is provided on the front side in the insertion / removal direction of the photoconductor unit 13 and the developing device 14. The pedestal 130 is provided at a position in front of the device housing 100 where it does not overlap the first guide 110 and the second guide 120 in a plan view, and supports the photoconductor unit 13 and the developing device 14 to be inserted from below in the direction of gravity. The pedestal 130 is at a height where it does not come into contact with the photoconductor unit 13 and the developing device 14 inserted into the device housing 100 (see FIG. 2).

[0054] A third guide 131 is provided on the upper surface of the base 130. The third guide 131 is formed on the base 130 so as to protrude upward and extend in the insertion / removal direction. The third guide 131 is adapted to fit into the guide groove 48 of the developing device 14 placed on the base 130 before the second hooks 46, 47 of the developing device 14 engage with the second guides 120, 121, thereby restricting the left-right movement of the developing device 14. This makes it possible to stabilize the posture of the developing device 14 when it is inserted into the device housing 100. As shown in FIG. 3, guides 132 may be provided on the upper surface of the base 130 at both ends in a direction intersecting the insertion / removal direction of the developing device 14 to regulate the left and right movement of the developing device 14.

[0055] (2.4) Installation of the photoconductor unit 13 and the developing device 14 Fig. 4 is a perspective view for explaining the attachment of the developing device 14 to the device housing 100, Fig. 5 is a perspective view for explaining the attachment of the photoconductor unit 13 to the device housing 100, and Fig. 6 is a front sectional view for explaining the attachment of the photoconductor unit 13 in a state in which the developing device 14 has been attached first. The attachment of the photoconductor unit 13 and the developing device 14 will be explained below with reference to the drawings.

[0056] As shown in Fig. 4, when the developing device 14 is mounted in the device housing 100, first, the rear side of the developing device 14 in the insertion / removal direction is placed on the pedestal 130 and supported from below in the direction of gravity. At this time, the developing device 14 is mounted so that the guide groove 48 of the developing device 14 shown in Fig. 3 fits into the third guide 131 on the pedestal 130 in the insertion / removal direction. As a result, the heavy developing device 14 is temporarily supported from below in the weight direction, and the developing device 14 can be mounted in the longitudinal direction from the front of the device housing 100.

[0057] Then, while being supported by the base 130, the developing device 14 is slid toward the second guides 120, 121, and the second hook 46 of the developing device 14 is placed on the second guide 120 (see arrow R1 in FIG. 4) and the second hook 47 is placed on the second guide 121 (see arrow R2 in FIG. 4), and then moved toward the back side. As a result, the developing device 14 is held in a state where it is suspended by the second hooks 46, 47 from the second guides 120, 121 of the device housing 100, making it easy to replace the unit.

[0058] When mounting the photosensitive unit 13 in the device housing 100, as shown in FIG. 5, the developing device 14 is mounted in the device housing 100 first, and then the rear side of the photosensitive unit 13 in the insertion / removal direction is placed on the base 130 and supported from below in the direction of gravity. Then, while being supported by the base 130, the photoconductor unit 13 is slid toward the first guide 110 (see arrow R3 in FIG. 5), and the first hook 37 of the photoconductor unit 13 is placed on the first guide 110 and moved toward the rear side. At this time, as shown in FIG. 6, the fifth guide 38 provided below the photoconductor unit 13 on the side facing the previously installed developing device 14 is guided by the fourth guide 49 provided on the underside of the developing device 14, so that the insertion posture of the photoconductor unit 13 is stabilized. That is, the rotation of the photoconductor unit 13 suspended by the first hook 37 on the first guide 110 (see arrow R4 in FIG. 6) about the first hook 37 is regulated by the fourth guide 49 provided on the developing device 14. This makes it easy to replace the unit while preventing damage to the photoconductor drum 31.

[0059] (2.5) Function of the 5th guide FIG. 7A is a diagram for explaining the air flow caused by the rotation of the developing roll 42 and the photosensitive drum 31, and FIG. 7B is a diagram for explaining the division of the air flow by the fifth guide 38. As shown in FIG. As shown in Fig. 7(a), the developing roll 42 rotates while holding the developer on the outer peripheral surface of the developing sleeve 42A by the magnetic force of the magnet 42B, thereby transporting and supplying the developer to the electrostatic latent image on the photoconductor drum 31 which rotates in the opposite direction. For this reason, an air flow (see arrow F in the figure) is formed as a rotational flow on the downstream side of the rotation direction of the developing roll 42. This air contains cloud toner generated by development, and the cloud toner accumulates around the fifth guide 38, and there is a risk that a part of the cloud toner may fall onto the intermediate transfer belt 51 which circulates below the photoconductor unit 13 and the developing device 14, for example.

[0060] The fifth guide 38 according to the present embodiment is formed below the photosensitive unit 13, with a gap between it and the photosensitive drum 31, and extends from the front side to the rear side of the photosensitive unit 13. As shown in Fig. 7(b), the fifth guide 38 has a guide member 38B having a substantially triangular cross section with an apex at the top (Z direction) attached to a metal plate 38A having an L-shaped cross section. The plate 38A is provided extending from the front side to the rear side of the unit housing 35, and also serves as a tie bar that reinforces the unit housing 35.

[0061] Guide member 38B is made of synthetic resin, and the triangular shape is composed of inclined surfaces with an inclination angle exceeding the angle of repose of toner. The angle of repose of toner varies depending on the type of developer and the usage environment such as temperature and humidity. As a result, even if cloud toner adheres to the surface of guide member 38B, the toner on the adhered toner slides off, and it is possible to prevent toner from accumulating and falling off the surface of guide member 38B.

[0062] 7(b), the triangular shape of the guide member 38B is formed such that a surface 38Ba facing the photosensitive drum 31 has a predetermined gap G with respect to the curvature of the photosensitive drum 31. As a result, the air flow formed on the downstream side in the rotation direction of the developing roll 42 is divided into the photosensitive drum 31 side (arrow f1 in the figure) and the developing device 14 side (arrow f2 in the figure) with the apex 38Bb of the guide member 38B as the base point, thereby suppressing the accumulation of the toner cloud.

[0063] Although the embodiment of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the gist of the present invention described in the claims. For example, in this embodiment, an intermediate transfer type image forming apparatus 1 equipped with an intermediate transfer belt as a belt unit has been described, but the present invention can also be applied to a direct transfer type image forming apparatus in which a toner image on a photosensitive drum is transferred and transported by contacting the photosensitive drum via a recording medium held on a transport belt. Furthermore, the present invention can be applied not only to a tandem type image forming apparatus, but also to an image forming apparatus having one photoconductor unit and a developing device. [Explanation of symbols]

[0064] 1. Image forming device 10. Image forming section 13 Photoconductor unit 31 photoconductor drum, 35 unit housing, 37 first hook, 38 fifth guide 14. Developing device 41...Developing housing, 42...Developing roll, 46, 47...Second hook, 48...Guide groove, 49...Fourth guide 20...Paper feed device 30....Paper ejection section 100: device housing, 110: first guide, 120, 121: second guide, 130: base 131···Third Guide

Claims

1. a first guide provided in a device housing for suspending and holding a first unit having an image carrier so as to be movable in an insertion / removal direction; a second guide provided in the device housing for suspending and holding a second unit having a developer holder so as to be movable in an insertion / removal direction; a base that is integrally provided on the device housing so as not to protrude from the device housing on the front side in the insertion / removal direction with respect to the first guide and the second guide, supports the first unit and the second unit in the middle of being inserted into the device housing from below in the gravity direction, and does not come into contact with the first unit and the second unit positioned in the device housing; 1. An image forming apparatus comprising:

2. a third guide is provided on the base, the third guide being fitted with the second unit and restricting movement of the first unit in a direction intersecting with an insertion / removal direction; 2. The image forming apparatus according to claim 1,

3. The first unit has a hook shape that engages with the first guide.

3. The image forming apparatus according to claim 1, wherein the first and second electrodes are arranged in a first direction.

4. The second unit has a hook shape that engages with the second guide.

3. The image forming apparatus according to claim 1, wherein the first and second electrodes are arranged in a first direction.

5. The second unit has a fourth guide that guides the insertion and removal of the first unit.

5. The image forming apparatus according to claim 1, wherein the first and second electrodes are arranged in a first direction.

6. the first unit has a fifth guide that guides the insertion and removal of the first unit to the fourth guide; 6. The image forming apparatus according to claim 5,

7. the fifth guide has a cross-sectional shape of a substantially triangular shape having an apex at an upper portion and is shaped to divide air flows accompanying rotation of the image carrier and the developer carrier; 7. The image forming apparatus according to claim 6,

8. the triangular shape is composed of inclined surfaces having an inclination angle exceeding the angle of repose of the toner; 8. The image forming apparatus according to claim 7,

9. the triangular shape has an inclined surface having a predetermined gap with respect to the curvature of the image carrier as one side; 9. The image forming apparatus according to claim 7, wherein the image forming apparatus is a multi-color image forming apparatus.

10. The fifth guide is a tie bar connecting both ends of the first unit in an insertion / removal direction.

10. The image forming apparatus according to claim 6, wherein the image forming apparatus is a multi-color image forming apparatus.

11. the image carrier is a photoconductor drum, The first unit is a drum unit.

11. The image forming apparatus according to claim 1,

Images