Image forming device

Abstract

To provide an image forming apparatus that can guide outside air taken in by intake fans toward a plurality of units through ducts while ensuring a sufficient amount of blast.SOLUTION: A left side intake unit 124 is disposed on a left side face of an image forming apparatus closer to a developing device arranged on the left side with respect to the center, and an intake port 171a is formed in a front face and on the left side with respect to the center closer to the left side intake unit 124. A right side intake unit 126 is disposed on a right side face of the image forming apparatus closer to a developing device arranged on the right side with respect to the center, and an intake port 172a is formed in the right side face closer to the right side intake unit 126. The intake ports are formed separately as the intake port 171a formed closer to the left side intake unit 124 and the intake port 172a formed closer to the right side intake unit 126. With this formation, outside air taken in by the left side intake unit 124 and the right side intake unit 126 is guided toward the plurality of developing devices through ducts while a sufficient amount of blast is ensured.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus such as a printer, a copying machine, a facsimile machine, or a multifunction machine. [Background technology]

[0002] An image forming apparatus has multiple image forming units (also called image forming stations) that form toner images on photosensitive drums. In each image forming unit, for example, a conveying screw stirs and circulates toner within a developing unit, generating heat in response to this toner stirring action. However, if the developing unit becomes too hot, the toner temperature will rise, causing image defects. Therefore, conventionally, the developing unit is cooled by an air flow created by external air drawn in from outside the image forming apparatus by an intake fan (Patent Document 1).

[0003] In the device described in Patent Document 1, one intake fan and multiple development units are connected by a tubular duct, and the single intake fan draws in outside air through an intake port provided on one side of the device and guides it toward the multiple development units.

[0004] In addition, in the charging unit that charges the surface of the photosensitive drum, an air flow may be formed to collect discharge products such as ozone released by corona discharge. In the device described in Patent Document 2, branch ducts are provided to guide outside air drawn in by an intake fan to the charging units of each image forming unit, so that ozone generated during charging can be collected. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-41562 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-218420 Summary of the Invention [Problem to be solved by the invention]

[0006] Recently, commercial printing image forming apparatuses have been used, capable of forming toner images on a larger number of recording materials in a shorter time. Compared to office printing apparatuses and home printing apparatuses, commercial printing apparatuses tend to be larger due to the large size of each of the multiple image forming units mounted in parallel in a housing. Furthermore, commercial printing image forming apparatuses generally have faster printing speeds than office printing apparatuses, which tend to increase the temperature rise in the development unit and the generation of discharge products in the charging unit. Image forming apparatuses with such high printing speeds require increased airflow for cooling the development unit and for collecting discharge products in the charging unit. Therefore, as in the image forming apparatuses described in Patent Documents 1 and 2, a duct could be installed to connect outside air drawn in from one side of the image forming apparatus by an intake fan to the multiple development units and charging units. However, in the case of commercial printing image forming apparatuses with high printing speeds, the apparatus itself is large and requires a large amount of airflow to each unit, making it difficult to ensure sufficient airflow for units far from the air intake port on one side of the image forming apparatus.

[0007] SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide an image forming apparatus that can guide outside air drawn in by an intake fan toward a plurality of units via a duct while ensuring a sufficient volume of air being blown therethrough. [Means for solving the problem]

[0008] An image forming apparatus according to one embodiment of the present invention is an image forming apparatus that forms an image on a recording material, and includes a housing, a plurality of image forming sections that are arranged along a first direction, including at least a first image forming section having a first photosensitive member and a first developing unit, and a second image forming section having a second photosensitive member and a second developing unit, a first air intake unit that has a first fan that draws in outside air from a first air intake port and sends the drawn in outside air to the first developing unit, and a second air intake unit that has a second fan that draws in outside air from a second air intake port and sends the drawn in outside air to the second developing unit, and the first image forming section is the image forming section that is closest to a first end of the housing among the plurality of image forming sections in the first direction. the second image forming unit is arranged in a position closest to a second end of the housing opposite to the first end among the plurality of image forming units in the first direction, the distance from the first end to the first fan in the first direction is shorter than the distance from the first end to the first image forming unit, and the distance from the first end to the first air intake port is shorter than the distance from the first end to the second image forming unit, the distance from the second end to the second fan in the first direction is shorter than the distance from the second end to the second image forming unit, and the distance from the second end to the second air intake port is shorter than the distance from the second end to the first image forming unit. another housing is connected to the first end side of the housing in the first direction so as to be able to deliver a recording material, the first air intake port is formed in a second surface intersecting the first surface facing the another housing, and the second air intake port is formed in a third surface on the side of the second end facing the first surface in the first direction, It is characterized by: Further, an image forming apparatus according to one embodiment of the present invention is an image forming apparatus that forms an image on a recording material, and includes a housing, a plurality of image forming sections that include at least a first image forming section having a first photosensitive member and a first developing unit, and a second image forming section having a second photosensitive member and a second developing unit, and are arranged along a first direction; a first intake unit that has a first fan that draws in outside air from a first intake port and sends the drawn-in outside air to the first developing unit; and a second intake unit that has a second fan that draws in outside air from a second intake port and sends the drawn-in outside air to the second developing unit, wherein the first image forming section is disposed at a position closest to a first end of the housing among the plurality of image forming sections in the first direction, and the second image forming section is disposed at a second end of the housing opposite to the first end among the plurality of image forming sections in the first direction. the first end of the housing is disposed at a position closest to the first end of the housing, the distance from the first end to the first fan in the first direction is shorter than the distance from the first end to the first image forming unit, and the distance from the first end to the first air intake port is shorter than the distance from the first end to the second image forming unit, the distance from the second end to the second fan in the first direction is shorter than the distance from the second end to the second image forming unit, and the distance from the second end to the second air intake port is shorter than the distance from the second end to the first image forming unit, the housing has four pillars arranged on all four sides, and the first air intake unit and the second air intake unit are supported by the pillars on the front side and the rear side such that the first fan and the second fan are located closer to the rear side than the two pillars on the front side of the pillars. Furthermore, an image forming apparatus according to one embodiment of the present invention is an image forming apparatus that forms an image on a recording material, and includes a housing, a plurality of image forming sections that include at least a first image forming section having a first photosensitive member and a first developing unit, and a second image forming section having a second photosensitive member and a second developing unit, and are arranged along a first direction; a first intake unit that has a first fan that draws in outside air from a first intake port and sends the drawn in outside air to the first developing unit; a second intake unit that has a second fan that draws in outside air from a second intake port and sends the drawn in outside air to the second developing unit; an opening / closing cover that is provided on a front surface of the housing so as to be openable and closable; and an inner cover unit that is disposed on the housing so as to face an inner surface of the opening / closing cover in a closed state, wherein the first image forming section is disposed at a position that is closest to a first end of the housing among the plurality of image forming sections in the first direction, and the second image forming section is disposed at a position that is closest to a first end of the housing among the plurality of image forming sections in the first direction. The inner cover unit is arranged at a position in the forming unit closest to a second end of the housing opposite the first end, and in the first direction, the distance from the first end to the first fan is shorter than the distance from the first end to the first image forming unit, and the distance from the first end to the first air intake port is shorter than the distance from the first end to the second image forming unit, and in the first direction, the distance from the second end to the second fan is shorter than the distance from the second end to the second image forming unit, and the distance from the second end to the second air intake port is shorter than the distance from the second end to the first image forming unit, and the inner cover unit has a first relay duct connected to the first air intake unit and guiding the outside air sucked in by the first fan toward the first developing unit, and a second relay duct connected to the second air intake unit and guiding the outside air sucked in by the second fan toward the second developing unit.

[0009] An image forming apparatus according to one embodiment of the present invention is an image forming apparatus that forms an image on a recording material, and includes a housing, a plurality of image forming units that include at least a first image forming unit having a first photosensitive member and a first charging unit, and a second image forming unit having a second photosensitive member and a second charging unit, and are arranged along a first direction; a first intake unit that has a first fan that draws in outside air from a first intake port and sends the drawn-in outside air to the first charging unit; and a second intake unit that has a second fan that draws in outside air from a second intake port and sends the drawn-in outside air to the second charging unit, and the first image forming unit is the image forming unit that is closest to a first end of the housing among the plurality of image forming units in the first direction. the second image forming unit is arranged in a position closest to a second end of the housing opposite to the first end among the plurality of image forming units in the first direction, the distance from the first end to the first fan in the first direction is shorter than the distance from the first end to the first image forming unit, and the distance from the first end to the first air intake port is shorter than the distance from the first end to the second image forming unit, the distance from the second end to the second fan in the first direction is shorter than the distance from the second end to the second image forming unit, and the distance from the second end to the second air intake port is shorter than the distance from the second end to the first image forming unit. another housing is connected to the first end side of the housing in the first direction so as to be able to deliver a recording material, the first air intake port is formed in a second surface intersecting the first surface facing the another housing, and the second air intake port is formed in a third surface on the side of the second end facing the first surface in the first direction, It is characterized by: Further, an image forming apparatus according to one embodiment of the present invention is an image forming apparatus that forms an image on a recording material, and includes a housing, a plurality of image forming units including at least a first image forming unit having a first photosensitive member and a first charging unit, and a second image forming unit having a second photosensitive member and a second charging unit, the image forming units being arranged along a first direction, a first intake unit having a first fan that draws in outside air from a first intake port and sending the drawn-in outside air to the first charging unit, and a second intake unit having a second fan that draws in outside air from a second intake port and sending the drawn-in outside air to the second charging unit, the first image forming unit being disposed at a position closest to a first end of the housing among the plurality of image forming units in the first direction, and the second image forming unit being disposed at a second end of the housing opposite to the first end among the plurality of image forming units in the first direction. the first end of the housing is disposed at a position closest to the first end of the housing, the distance from the first end to the first fan in the first direction is shorter than the distance from the first end to the first image forming unit, and the distance from the first end to the first air intake port is shorter than the distance from the first end to the second image forming unit, the distance from the second end to the second fan in the first direction is shorter than the distance from the second end to the second image forming unit, and the distance from the second end to the second air intake port is shorter than the distance from the second end to the first image forming unit, the housing has four pillars arranged on all four sides, and the first air intake unit and the second air intake unit are supported by the pillars on the front side and the rear side such that the first fan and the second fan are located closer to the rear side than the two pillars on the front side of the pillars. Furthermore, an image forming apparatus according to one embodiment of the present invention is an image forming apparatus that forms an image on a recording material, and includes a housing, a plurality of image forming units including at least a first image forming unit having a first photosensitive member and a first charging unit, and a second image forming unit having a second photosensitive member and a second charging unit, and are arranged along a first direction; a first intake unit having a first fan that draws in outside air from a first intake port and sends the drawn in outside air to the first charging unit; a second intake unit having a second fan that draws in outside air from a second intake port and sends the drawn in outside air to the second charging unit; an opening / closing cover that is provided on a front surface of the housing so as to be openable and closable; and an inner cover unit that is disposed on the housing so as to face an inner surface of the opening / closing cover in a closed state, wherein the first image forming unit is disposed at a position closest to a first end of the housing among the plurality of image forming units in the first direction, and the second image forming unit is disposed at a position closest to a first end of the housing among the plurality of image forming units in the first direction. The inner cover unit is arranged at a position in the forming unit closest to a second end of the housing opposite the first end, and in the first direction, the distance from the first end to the first fan is shorter than the distance from the first end to the first image forming unit, and the distance from the first end to the first air intake port is shorter than the distance from the first end to the second image forming unit, and in the first direction, the distance from the second end to the second fan is shorter than the distance from the second end to the second image forming unit, and the distance from the second end to the second air intake port is shorter than the distance from the second end to the first image forming unit, and the inner cover unit has a first relay duct connected to the first air intake unit and guiding the outside air sucked in by the first fan toward the first charging unit, and a second relay duct connected to the second air intake unit and guiding the outside air sucked in by the second fan toward the second charging unit. [Effects of the Invention]

[0010] According to the present invention, it is possible to achieve, with a simple configuration, guiding the outside air drawn in by the intake fan through the duct toward a plurality of units while ensuring a sufficient airflow rate. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram showing an image forming system including an image forming apparatus according to an embodiment of the present invention; [Figure 2] FIG. 2 is a left perspective view showing the image forming apparatus with the front door open. [Figure 3]1A and 1B are a left perspective view and a right perspective view, respectively, showing a state in which the front door of the image forming apparatus is closed. [Figure 4] FIG. 4 is a schematic diagram showing the arrangement of the left and right intake units in the first housing. [Figure 5] FIG. 4 is a perspective view showing a left air intake unit for drawing air into the developing device. [Figure 6] FIG. 4 is a perspective view showing a right-side intake unit for drawing air into the developing device. [Figure 7] FIG. 4 is a schematic diagram showing the inner surface side of an inner cover unit for drawing air into the developing device. [Figure 8] 5A and 5B are schematic diagrams illustrating airflow to a developing device, in which FIG. 5A is the present embodiment and FIG. 5B is a comparative example. [Figure 9] FIG. 4 is a schematic diagram illustrating an air flow to the charging device. [Figure 10] FIG. 10 is a schematic view showing the inner surface side of an inner cover unit for drawing air into the charging device. [Figure 11] FIG. 4 is a left perspective view for explaining an air intake port. [Figure 12] FIG. 12 is a schematic diagram showing the intake unit in the case of FIG. 11; DETAILED DESCRIPTION OF THE INVENTION

[0012] [First embodiment] <Image forming system> The schematic configuration of an image forming system including an image forming apparatus according to this embodiment will be described with reference to Fig. 1. The image forming system 1X shown in Fig. 1 includes an image forming apparatus 100 and a finisher apparatus 300. The image forming apparatus 100 and the finisher apparatus 300 are connected so that recording material S can be transferred between them. In this embodiment, the finisher apparatus 300 is a post-processing unit that can be added to the image forming apparatus 100 to expand its functionality, and can perform post-processing, described below, on recording material S on which a toner image has been fixed by the image forming apparatus 100. The image forming apparatus 100 and the finisher apparatus 300 are connected so that data can be transmitted and received between them via a communication interface capable of serial communication or parallel communication.

[0013] <Image forming device> The image forming apparatus 100 is a tandem-type electrophotographic full-color printer and includes a first housing 101a and a second housing 101b. The first housing 101a accommodates various devices and components, such as an image forming unit 700 that conveys the recording material S and transfers the toner image. The second housing 101b accommodates various devices and components, such as a fixing unit 800 that conveys the recording material S and fixes the toner image. The second housing 101b also includes an operation unit 200 on its front side, which includes a display unit capable of displaying various information and keys for inputting various information in response to user operation. The second housing 101b is located at one end (downstream) of the first housing 101a in the width direction of the image forming apparatus 100 (here, the conveyance direction of the recording material S at a secondary transfer unit T2, described later, the arrow X direction). The first housing 101a and the second housing 101b are connected to each other so that the recording material S can be transferred between them.

[0014] An electrical unit (not shown) having a power supply board may be disposed on the rear side of the first housing 101a and the second housing 101b. In this specification, the side on which a user stands when operating the operation unit 200 to operate the image forming apparatus 100 is referred to as the "front," and the opposite side is referred to as the "rear." In addition, the left side when viewing the image forming apparatus 100 from the front is referred to as the "left side," and the right side when viewing it from the front is referred to as the "right side."

[0015] Image forming apparatus 100 includes four image forming units Pa, Pb, Pc, and Pd that form yellow, magenta, cyan, and black images, respectively. Image forming apparatus 100 forms a toner image on recording material S in response to an image signal received from an original reading device 190 that reads an image signal from an original or from an external device (not shown) such as a personal computer. Image forming apparatus 100 of this embodiment is a large commercial printing device compared to office or home devices, in which each of the multiple image forming units mounted in parallel in first housing 101a is large.

[0016] In this embodiment, the image forming units Pa to Pd, primary transfer rollers 24a to 24d, intermediate transfer belt 130, multiple rollers 13 to 15, and outer secondary transfer roller 11 constitute an image forming unit 700 that forms a toner image on recording material S. Examples of recording material S include plain paper, cardboard, rough paper, textured paper, coated paper, plastic film, and cloth.

[0017] As shown in FIG. 1, the image forming stations Pa to Pd are arranged in a line along the direction of movement of the intermediate transfer belt 130. The intermediate transfer belt 130 is stretched around a plurality of rollers (13, 14, 15) and moved in the direction of arrow R2. The intermediate transfer belt 130 carries and transports a toner image that is primarily transferred as described below. An outer secondary transfer roller 11 is arranged at a position opposite the inner secondary transfer roller 14 that stretches the intermediate transfer belt 130 and sandwiches the intermediate transfer belt 130 therebetween, forming a secondary transfer station T2 that transfers the toner image on the intermediate transfer belt 130 to the recording material S. A fixing unit 800 is arranged downstream of the secondary transfer station T2 in the recording material transport direction.

[0018] A plurality of cassettes 10 (two in this example) containing recording materials S are arranged below the image forming apparatus 100. These cassettes 10 contain recording materials S of different sizes and thicknesses, and a recording material S is selectively transported from one of the cassettes 10. The recording material S is transported by transport rollers 16 from the cassette 10 through a transport path toward registration rollers 12. Thereafter, the registration rollers 12 rotate in synchronization with the toner image formed on the intermediate transfer belt 130, thereby transporting the recording material S toward the secondary transfer unit T2. Note that the recording material S is not limited to that contained in the cassette 10, and a recording material S placed on a manual feed unit (not shown) may also be transported.

[0019] The image forming units Pa, Pb, Pc, and Pd have substantially the same configuration except for the toner image colors they develop. Therefore, the yellow image forming unit Pa will be described here as a representative, and descriptions of the other image forming units Pb, Pc, and Pd will be omitted.

[0020] A cylindrical photosensitive drum 3a is disposed in the image forming station Pa. The photosensitive drum 3a is rotated by a motor (not shown). Around the photosensitive drum 3a, a charging device 2a as a charging unit, an exposure device La, a developing device 1a, a primary transfer roller 24a, and a drum cleaning device 4a are disposed.

[0021] The process of forming, for example, a full-color image using the image forming apparatus 100 will be described. First, when the image forming operation starts, the surface of the rotating photosensitive drum 3a is uniformly charged by the charging device 2a. The charging device 2a is, for example, a corona charger that irradiates the surface of the photosensitive drum 3a with charged particles due to corona discharge, thereby charging the surface of the photosensitive drum 3a to a uniform potential. Next, the photosensitive drum 3a is scanned and exposed by a laser beam corresponding to an image signal emitted from the exposure device La. As a result, an electrostatic latent image corresponding to the image signal is formed on the surface of the photosensitive drum 3a. The electrostatic latent image formed on the photosensitive drum 3a is developed into a visible toner image using a developer containing toner and carrier contained in the developing device 1a. In other words, the toner image is developed on the photosensitive drum 3a by supplying toner by the developing device 1a. Note that within the developing devices 1a to 1d, the developer is circulated and conveyed while being stirred by a conveying screw (not shown).

[0022] The toner image formed on the photosensitive drum 3a is primarily transferred onto the intermediate transfer belt 130 at a primary transfer section T1 formed between the photosensitive drum 3a and a primary transfer roller 24a disposed across the intermediate transfer belt 130. At this time, a primary transfer voltage is applied to the primary transfer roller 24a. Any toner remaining on the surface of the photosensitive drum 3a after the primary transfer is removed by a drum cleaning device 4a.

[0023] This operation is performed sequentially at each of the yellow, magenta, cyan, and black image forming units Pa to Pd, and the four color toner images are superimposed on the intermediate transfer belt 130. Thereafter, the recording material S stored in the cassette 10 is conveyed to the secondary transfer unit T2 in accordance with the timing of the formation of the toner images. Then, by applying a secondary transfer voltage to the outer secondary transfer roller 11, the full-color toner images formed on the intermediate transfer belt 130 are secondarily transferred all at once onto the recording material S. Note that any toner remaining on the intermediate transfer belt 130 after the secondary transfer is removed by a belt cleaning device (not shown).

[0024] In this embodiment, the photosensitive drums 3a and 3b correspond to first photosensitive bodies, and the photosensitive drums 3c and 3d correspond to second photosensitive bodies. Furthermore, the developing devices 1a and 1b correspond to first developing units, and the developing devices 1c and 1d correspond to second developing units. Furthermore, the charging devices 2a and 2b correspond to first charging units, and the charging devices 2c and 2d correspond to second charging units.

[0025] The recording material S onto which the toner image has been transferred is transported to a fixing unit 800. The fixing unit 800 fixes the toner image to the recording material S by applying heat and pressure to the recording material S onto which the toner image has been transferred. In this embodiment, after heat and pressure have been applied to the recording material S by a first fixing device 81, it is possible to selectively apply further heat and pressure to the recording material S by a second fixing device 91. A fixing switching flapper 95 switches between the fixing unit 800 transporting the recording material S towards the second fixing device 91 after passing through the first fixing device 81, or transporting the recording material S bypassing the second fixing device 91 after passing through the first fixing device 81.

[0026] The second fixer 91 is disposed downstream of the first fixer 81 in the conveying direction of the recording material S. The second fixer 91 is selectively used for purposes such as imparting additional gloss to the toner image on the recording material S fixed by the first fixer 81. For example, if the recording material S is coated paper such as glossy paper or synthetic paper, the recording material S that has passed through the first fixer 81 is conveyed through a fixing route 30a so that fixing is performed by both the first fixer 81 and the second fixer 91. On the other hand, if the recording material S is uncoated paper such as plain paper, the recording material S that has passed through the first fixer 81 is conveyed through a fixing bypass route 30b that avoids the second fixer 91 so that fixing is performed by the first fixer 81 but not by the second fixer 91.

[0027] Since the first fixing device 81 and the second fixing device 91 may have the same configuration, the first fixing device 81 will be described here as an example. The first fixing device 81 has a fixing roller 82 (or fixing belt) that is rotatable in contact with the surface of the recording material S on which the toner image is fixed, and a pressure belt 83 (or pressure roller) that is in pressure contact with the fixing roller 82 to form a fixing nip portion. At least one of the fixing roller 82 and the pressure belt 83 is heated by a heater (not shown). In the fixing nip portion formed by the fixing roller 82 and the pressure belt 83, the first fixing device 81 applies heat and pressure to the recording material S on which the toner image has been formed as the recording material S is nipped and conveyed, thereby fixing the toner image to the recording material S.

[0028] In this embodiment, the image forming apparatus 100 is capable of double-sided printing. In the case of single-sided printing, the recording material S on which the toner image has been fixed is conveyed to the discharge conveyance path 150 and discharged to the outside of the image forming apparatus 100. In the case of double-sided printing, the recording material S on which the toner image has been fixed is conveyed to the double-sided reversing conveyance path 600. The double-sided reversing conveyance path 600 is formed across the first housing 101a and the second housing 101b. In the double-sided reversing conveyance path 600, the recording material S is reversed by a switchback operation, and the front and back sides of the recording material S are swapped. The reversed recording material S is conveyed toward the registration rollers 12, and is conveyed by the registration rollers 12 to the secondary transfer unit T2 with the unprinted back side facing the intermediate transfer belt 130. In the secondary transfer unit T2, the full-color toner image formed on the intermediate transfer belt 130 is secondarily transferred all at once to the recording material S (back side). Thereafter, the toner image is fixed on the recording material S by the fixing unit 800, and the recording material S is discharged to the outside of the image forming apparatus 100 with the side on which the image was just formed (image forming surface) facing upward. Switching between the discharge conveying path 150 and the double-sided reversing conveying path 600 is performed by a conveying switching flapper 160. Note that, although the fixing unit 800 is configured to include two fixing devices in this embodiment, it may also be configured to include only one fixing device. Also, a cooling device for cooling the recording material S on which the toner image has been fixed by the fixing unit 800 may be configured to be provided in the second housing 101b.

[0029] A finisher device 300 is connected to the image forming apparatus 100 so that the recording material S can be delivered, and the recording material S discharged from the image forming apparatus 100 is transported to the finisher device 300. The recording material S transported to the finisher device 300 undergoes post-processing such as punching to make holes in the recording material S or stapling to bundle and staple multiple sheets of recording material S. In the finisher device 300, the punched recording material S is discharged to an upper discharge tray 301, and the stapled bundle of recording materials S is discharged to a lower discharge tray 302.

[0030] The airflow configuration of the image forming apparatus 100 will be described below with reference to Fig. 1 and Fig. 2 to Fig. 8. Fig. 2 is a left-side perspective view showing the image forming apparatus 100 with its front door open. Fig. 3(a) is a left-side perspective view showing the image forming apparatus 100 with its front door closed, and Fig. 3(b) is a right-side perspective view showing the image forming apparatus 100 with its front door closed. Fig. 4 is a schematic diagram showing the arrangement of the left-side intake unit and the right-side intake unit in the first housing.

[0031] As shown in FIG. 2, a left front door 170a and a right front door 170b are provided on the front of the first housing 101a as opening / closing covers, so that they can be opened and closed like double doors with the border at approximately the center as shown. An inner cover 173 is also provided on the front of the first housing 101a, inside the left front door 170a and the right front door 170b. The inner cover 173 is provided to prevent a user from accidentally touching moving parts or electrical wiring inside the first housing 101a when the user opens the front doors (170a, 170b). However, the inner cover 173 is detachably attached to the first housing 101a with screws or the like so that a service technician can perform maintenance work. The inner cover 173 has openings that allow the image forming units Pa to Pd (shown by dotted lines) to be individually inserted and removed from the first housing 101a, and an inner cover unit 125 is detachably attached to the inner cover 173 so as to cover the image forming units Pa to Pd.

[0032] In this embodiment, image forming units Pa and Pb are supported by first housing 101a at positions facing left front door 170a in the closed state, and image forming units Pc and Pd are supported by first housing 101a at positions facing right front door 170b in the closed state. In other words, image forming units Pa and Pb are located to the left of the center when viewed from the front, and image forming units Pc and Pd are located to the right of the center when viewed from the front.

[0033] As shown in FIGS. 2 and 3A, an intake cover 171 is provided above the left front door 170a, and an intake port 171a serving as a first intake port is formed in the intake cover 171. In other words, the intake port 171a faces the front of the image forming apparatus 100 and is formed in the intake cover 171 serving as an exterior cover. A left intake unit 124 having a fan that draws in outside air through the intake port 171a is disposed on the left side surface of the first housing 101a. The outside air drawn in through the intake port 171a is guided toward the developing devices 1a and 1b via the left intake unit 124 and the inner cover unit 125. In this embodiment, a second housing 101b, which is another housing, is connected to the left side surface of the first housing 101a, which is downstream in the conveyance direction of the recording material S (see FIG. 1). Therefore, the air intake 171a is not formed on the left side surface (first surface) of the first housing 101a facing the second housing 101b, but on the front surface (second surface) that intersects with the left side surface (first surface) of the first housing 101a.

[0034] 3(b), a right cover 172 is provided on the right side surface of first housing 101a, and an air intake port 172a serving as a second air intake port is formed in right cover 172. In other words, air intake port 172a is formed in right cover 172, facing the right side of image forming apparatus 100. A right air intake unit 126 having a fan that draws in outside air through air intake port 172a is disposed on the right side surface of first housing 101a. The outside air drawn in through air intake port 172a is guided to developing devices 1c and 1d via right air intake unit 126 and inner cover unit 125. In this embodiment, since no other housing is connected to the right side of the first housing 101a, which is the other end of the image forming device 100 (here, the upstream side in the conveying direction of the recording material S), the air intake 172a is formed on the upstream right side (third surface) opposite the left side (first surface) of the first housing 101a in the conveying direction of the recording material S.

[0035] In this embodiment, the first fixing unit 81 and the second fixing unit 91 supported by the second housing 101b generate heat, and are therefore cooled by air cooling using a cooling mechanism (not shown). As a result, the second housing 101b exhausts air from an exhaust port (not shown) provided on the rear side. It is preferable that the outside air taken in through the air intake port 171a and the air intake port 172a be low in temperature. For this reason, the air intake port 171a and the air intake port 172a are formed as far away as possible from the rear side of the second housing 101b, where the temperature is likely to rise, on the front or side of the first housing 101a.

[0036] 4, the support frame that supports the units in first housing 101a has four supports on all four sides: front supports 185a and 185b on the front side and rear supports 185c and 185d on the rear side. These front supports 185a and 185b and rear supports 185c and 185d are connected to bottom plate 185 and stand upright from bottom plate 185. Left air intake unit 124 is supported by spanning front support 185a and rear support 185c, and right air intake unit 126 is supported by spanning front support 185b and rear support 185d. The left air intake unit 124 and the right air intake unit 126 are supported so that the outlets 174a, 174b, 179b, and 179a for the outside air taken in by the development air intake fans 180a, 180b, 180c, and 180d respectively provided therein face the front.

[0037] The left-side intake unit 124 is supported by a front support column 185a and a rear support column 185c so that the developing intake fans 180a and 180b as first fans are located on the downstream end side of the first housing 101a in the conveyance direction of the recording material S. On the other hand, the right-side intake unit 126 is supported by a front support column 185b and a rear support column 185d so that the developing intake fans 180c and 180d as second fans are located on the upstream end side of the first housing 101a in the conveyance direction of the recording material S.

[0038] Furthermore, the left-side intake unit 124 and the right-side intake unit 126 are supported so that the development intake fans 180a and 180b of the left-side intake unit 124 and the development intake fans 180c and 180d of the right-side intake unit 126 are positioned behind the two front support pillars 185a and 185b on the front side, respectively. In this way, the operating noise of the development intake fans 180a to 180d is blocked by the front doors (170a and 170b, see FIG. 3(a)), allowing the user to operate the image forming apparatus 100 without worrying about the operating noise of these fans. In other words, the noise caused by the operating noise of these fans can be suppressed.

[0039] <Intake unit> The left-side intake unit 124 as the first intake unit and the right-side intake unit 126 as the second intake unit will be described with reference to FIG. 1 and FIGS. 5 to 8(b). As shown in FIG. 5, the left-side intake unit 124 has a left-side main body duct 174, development intake fans 180a and 180b, and a side duct 1741. The development intake fans 180a and 180b are sirocco fans for cooling the development devices 1a and 1b supported by the first housing 101a. The left-side main body duct 174 is a duct having a space formed therein that communicates with an intake port 171a formed in the front of the image forming apparatus 100.

[0040] The developing air intake fans 180a, 180b and the side duct 1741 are disposed on the left side surface of the left main body duct 174. That is, communication ports that communicate with the developing air intake fans 180a, 180b are formed on the left side surface of the left main body duct 174, and outside air is drawn in from the air intake port 171a in response to the operation of the developing air intake fans 180a, 180b and passes through the inside of the left main body duct 174. Developing ducts 181a, 181b are formed inside the side duct 1741. The side duct 1741 and the developing air intake fans 180a, 180b are connected so that the outside air that has passed through the developing air intake fans 180a, 180b passes through the developing ducts 181a, 181b, respectively.

[0041] 8(a), outside air taken in through the air intake 171a is sent to the developing devices 1a and 1b via the left-side main body duct 174, the development air intake fans 180a and 180b, the development ducts 181a and 181b, and the inner cover unit 125. It is preferable to provide a filter (not shown) in the flow path from the air intake 171a to the left-side main body duct 174 in order to remove dust and the like from the outside air taken in through the air intake 171a.

[0042] Next, the right-side intake unit 126 will be described with reference to Figure 6. As shown in Figure 6, the right-side intake unit 126 has a right-side main body duct 176, development intake fans 180c and 180d, and a passing duct 179. The development intake fans 180c and 180d are sirocco fans for blowing outside air to the development devices 1c and 1d supported by the first housing 101a. The right-side main body duct 176 is a duct having a space formed therein that communicates with an intake port 172a formed on the right side surface of the image forming apparatus 100.

[0043] The developing air intake fans 180c and 180d are provided on the right side surface of the right main body duct 176. That is, the right main body duct 176 is formed with communication ports that communicate with the developing air intake fans 180c and 180d, and outside air taken in from the air intake port 172a in response to operation of the developing air intake fans 180c and 180d passes through the inside of the right main body duct 176. The passing duct 179 is formed with developing ducts 181c and 181d inside. The passing duct 179 is connected to the developing air intake fans 180c and 180d so that the outside air that has passed through the developing air intake fans 180c and 180d passes through the developing ducts 181c and 181d, respectively.

[0044] 8(a), the outside air taken in through the intake port 172a is sent to the developing devices 1c and 1d via the right-side main body duct 176, the development intake fans 180c and 180d, the development ducts 181c and 181d, and the inner cover unit 125. In order to remove dust and the like from the outside air taken in through the intake port 172a, it is preferable to place a filter (not shown) in the flow path from the intake port 172a to the right-side main body duct 176.

[0045] As described above, in this embodiment, the left-side intake unit 124 and the right-side intake unit 126 are used to blow outside air to the developing devices 1a to 1d. The left-side intake unit 124, which has the development intake fans 180a and 180b, is disposed on the left side of the first housing 101a of the image forming apparatus 100, close to the developing devices 1a and 1b, in order to blow outside air to the developing devices 1a and 1b, as viewed from the front. Furthermore, an intake port 171a is formed on the front surface of the image forming apparatus 100, close to the left of the center and close to the left-side intake unit 124, in order to allow the development intake fans 180a and 180b to draw in outside air. That is, the intake port 171a is formed downstream of the center of the first housing 101a, closer to the development intake fans 180a and 180b than the development intake fans 180c and 180d in the conveyance direction of the recording material S. Note that second housing 101b is connected to the left side surface of first housing 101a. By providing air intake port 171a on the front side surface of first housing 101a as in this embodiment, it is possible to prevent second housing 101b from blocking the intake of air from air intake port 171a.

[0046] On the other hand, in order to blow outside air to developing devices 1c and 1d, which are located to the right of the center when viewed from the front, a right-side intake unit 126 having developing device intake fans 180c and 180d is disposed on the right side of first housing 101a of image forming apparatus 100, close to developing devices 1c and 1d. An intake port 172a is formed on the right side of image forming apparatus 100, close to right-side intake unit 126, for drawing in outside air by developing device intake fans 180c and 180d. That is, intake port 172a is formed closer to one end than the center of first housing 101a in the width direction of image forming apparatus 100. Here, intake port 172a is formed upstream of the center of first housing 101a, closer to developing device intake fans 180c and 180d than developing device intake fans 180a and 180b in the conveyance direction of recording material S.

[0047] <Inner cover unit> Fig. 7 shows the inner cover unit 125 used in this embodiment. Fig. 7 is a schematic diagram showing the inner surface of the inner cover unit 125. In this embodiment, as shown in Fig. 7, flexible tubes 183a and 183b as first relay ducts and flexible tubes 183c and 183d as second relay ducts are arranged on the inner surface of the inner cover unit 125 as relay ducts through which outside air passes to cool the developing devices 1a to 1d. These flexible tubes 183a to 183d are attached to the inner surface of the inner cover unit 125 using, for example, wire saddles.

[0048] The flexible tubes 183a-183d are formed into a hollow cylindrical shape using resin such as PA6 (polyamide) or metal, and are bellows-shaped cylindrical members with numerous convex portions formed continuously at predetermined intervals on the outer periphery, making them freely bendable. When these flexible tubes 183a-183d are bent, the bending is restricted by the convex portions on the inner side of the bend (compression side), making them difficult to bend. Therefore, even when the flexible tubes 183a-183d are bent, the cross-sectional area remains the same as before bending, allowing them to guide outside air without changing the amount of airflow per unit time.

[0049] In this way, the outside air drawn in through the intake port 171a in conjunction with the operation of the development intake fans 180a and 180b passes through the left main body duct 174, development ducts 181a and 181b, and flexible tubes 183a and 183b, and flows toward the development devices 1a and 1b. On the other hand, the outside air drawn in through the intake port 172a in conjunction with the operation of the development intake fans 180c and 180d passes through the right main body duct 176, development ducts 181c and 181d, and flexible tubes 183c and 183d, and flows toward the development devices 1c and 1d.

[0050] In this embodiment, the flexible tubes 183a to 183d can be curved appropriately and stretched around the inner surface of the inner cover unit 125. In other words, by using the flexible tubes 183a to 183d, the degree of freedom in duct arrangement within a limited space is increased. Note that the routing of the flexible tubes 183a to 183d shown here is an example and is not limited to this.

[0051] The flexible tubes 183a to 183d are formed in a rectangular shape with a cross-sectional area of ​​25 mm x 20 mm and a maximum length of 550 mm. 3 / min, the pressure loss in the flexible tubes 183a to 183d is approximately 99 Pa. If the left-side intake unit 124 is provided with the development intake fan 180d and external air is sent to the development device 1d using a flexible tube, the length of the flexible tube will be 1100 mm, and the pressure loss in the flexible tube will be approximately 200 Pa. In other words, if the left-side intake unit 124 is provided with the development intake fan 180d to send external air to the development device 1d, the pressure loss will be doubled compared to this embodiment, and the development intake fan 180d will need to be a fan with a higher output. However, such a fan is difficult to adopt because it is large and expensive.

[0052] FIG. 8B shows a comparative example in which development intake fans 180a, 180b and development intake fans 180c, 180db are arranged on the front side of image forming apparatus 100, ahead of front support columns 185a, 185b.

[0053] In the comparative example shown in FIG. 8(b), development intake fans 180a-180d are disposed in front of front support columns 185a and 185b. Outside air drawn in through intake ports 171a and 172a reaches development intake fans 180a-180d via left-side main body duct 174 and right-side main body duct 176. In the comparative example, outside air can be sent to development devices 1a-1d without passing through side duct 1741, passing duct 179 (see FIGS. 5 and 6), and inner cover unit 125 (see FIG. 2) in the above-described embodiment. In other words, in the comparative example, side duct 1741, passing duct 179, and inner cover unit 125 are not required.

[0054] However, the distances between the front support columns 185a and 185b and the left and right front doors 170a and 170b are larger than those in this embodiment (FIG. 8(a)), as indicated by arrows A and B. In other words, in the comparative example, the area occupied in front of the support frame increases to accommodate the fan placement, resulting in an increase in the size of the device in the front-to-rear direction (arrow Y). More specifically, the area occupied in front of the conveyance path provided inside the support frame of the image forming device 100 increases. As a result, when the conveyance path is aligned with and connected to the second housing 101b or a post-processing device (e.g., the finisher device 300) connected downstream in the conveyance direction, the front cover of the first housing 101a protrudes beyond the front covers of the second housing 101b and the post-processing device, degrading the appearance. Furthermore, the comparative example shown in FIG. 8(b) does not include an inner cover 173 (see FIG. 2). However, an inner cover 173 is typically provided to prevent users from accidentally touching moving parts, electrical wiring, and the like inside the housing. In the comparative example, if inner cover 173 were provided, the occupied area would increase accordingly. In contrast, as shown in FIG. 8(a), in this embodiment, the increase in occupied area due to fan placement can be prevented. In other words, the image forming apparatus 100 is prevented from becoming larger in the front-to-rear direction.

[0055] As described above, in this embodiment, the left-side intake unit 124 is disposed on the left side of the image forming apparatus 100 near the developing devices 1a and 1b in order to blow outside air to the developing devices 1a and 1b, which are located to the left of the center when viewed from the front. The intake port 171a is formed on the front surface of the image forming apparatus 100, near the left-side intake unit 124, to allow the left-side intake unit 124 to draw in outside air. The right-side intake unit 126 is disposed on the right side of the image forming apparatus 100 near the developing devices 1c and 1d in order to blow outside air to the developing devices 1c and 1d, which are located to the right of the center when viewed from the front. The right-side intake unit 126 also has the intake port 172a formed on the right side of the image forming apparatus 100 near the right-side intake unit 126 to allow the right-side intake unit 126 to draw in outside air. In this way, the intake ports for drawing in outside air to be blown to the plurality of developing devices 1a to 1d are divided into intake port 171a formed on the side closer to left intake unit 124 and intake port 172a formed on the side closer to right intake unit 126. In this way, the outside air drawn in by left intake unit 124 and right intake unit 126 is guided through the ducts toward the plurality of developing devices 1a to 1d while ensuring a sufficient amount of air to be blown.

[0056] [Second embodiment] Next, as a second embodiment, the airflow configuration of the charging devices 2a to 2d will be described. FIG. 9 shows the charging device 2a as a representative example. As shown in FIG. 9, the charging device 2a ionizes the air around the charging wire 203a through corona discharge, generating ions to charge the surface of the photosensitive drum 3a. During corona discharge, the charging device 2a generates not only ions but also ozone. However, ozone easily corrodes stainless steel grids (not shown) included in the charging device 2a, and therefore must be collected. Therefore, to transport and collect ozone to the ozone collection filter 219a using external air, a primary intake duct 202a that blows external air to the charging device 2a and a primary exhaust duct 204a that exhausts air to the outside of the image forming apparatus 100 through the ozone collection filter 219a are provided near the charging device 2a.

[0057] The airflow configuration for supplying outside air to charging devices 2a-2d may be the same as the airflow configuration for supplying outside air to developing devices 1a-1d described above. Therefore, in the description of the airflow configuration for supplying outside air to developing devices 1a-1d described above, "development" can be replaced with "charging." That is, outside air drawn in through intake port 171a as charging intake fans 180a and 180b operate passes through left-side main body duct 174, charging ducts 181a and 181b, and flexible tubes 183a and 183b toward charging devices 2a and 2b. Meanwhile, outside air drawn in through intake port 172a as charging intake fans 180c and 180d operate passes through right-side main body duct 176, charging ducts 181c and 181d, and flexible tubes 183c and 183d toward charging devices 2c and 2d.

[0058] 1 and 9, charging devices 2a to 2d are disposed above developing devices 1a to 1d, and therefore flexible tubes 183a to 183d are disposed differently in inner cover unit 125. Fig. 10 is a schematic diagram showing the inner surface of inner cover unit 125 for drawing air into charging devices 2a to 2d.

[0059] 10, flexible tubes 183a to 183d are arranged on the inner surface of the inner cover unit 125 as relay ducts for passing outside air to be sent to the charging devices 2a to 2d. The flexible tubes 183a to 183d are attached to the inner surface of the inner cover unit 125 using, for example, a wire saddle. Note that the routing of the flexible tubes 183a to 183d shown here is an example and is not limited to this.

[0060] The flexible tubes 183a to 183d through which the outside air passes to be sent to the charging devices 2a to 2d are formed in a rectangular shape with a cross-sectional area of ​​25 mm x 20 mm and a maximum length of 500 mm. 3 / min, the pressure loss in the flexible tubes 183a-183d is approximately 309 Pa. If the charging intake fan 180d is provided in the left air intake unit 124 and external air is sent to the charging device 2d using a flexible tube, the length of the flexible tube will be 1000 mm and the pressure loss in the flexible tube will be approximately 618 Pa. In other words, if the charging intake fan 180d is provided in the left air intake unit 124 and external air is sent to the charging device 2d, the pressure loss will be doubled compared to this embodiment, and a higher-output fan will be required for the charging intake fan 180d. However, such a fan is difficult to adopt because it is large and expensive.

[0061] In this way, the airflow configuration of the first embodiment described above can also be adopted for the airflow configuration that sends outside air drawn in by the intake fans to the charging devices 2a to 2d. Therefore, for an image forming apparatus in which multiple units mounted in parallel in a housing are large and the printing speed is fast, requiring a large amount of air to be blown to the multiple units, it is possible to achieve with a simple configuration the outside air drawn in by the intake fans being guided through ducts to the multiple units while ensuring a sufficient amount of air to be blown. This provides the same effect as the first embodiment.

[0062] [Other embodiments] In the above-described embodiment, an example has been shown in which the second housing 101b, which is a separate housing, is connected to the left side surface of the first housing 101a, which is downstream in the conveyance direction of the recording material S (see FIG. 1), but this is not limiting. For example, the second housing 101b, which is a separate housing, may be connected to the right side surface of the first housing 101a, which is upstream in the conveyance direction of the recording material S. In such a case, the air intake 107a and the air intake 171b are formed at positions as shown in FIG. 11. That is, as shown in FIG. 11, the air intake 171a is formed on the left side surface of the image forming apparatus 100. On the other hand, the air intake 172a is formed on the front side and to the right of the center of the image forming apparatus 100.

[0063] FIG. 12 shows an intake unit in which intake ports 171a and 172a are formed at the positions shown in FIG. 11. As shown in FIG. 12, in this case, the left-side intake unit 124 and the right-side intake unit 126 are swapped left and right, compared to the case in which intake port 171a is formed in the front of image forming apparatus 100 and intake port 172a is formed on the right side of image forming apparatus 100 (see FIG. 4). However, as shown in FIG. 12, in intake unit 212 located to the left of the center of image forming apparatus 100, development intake fans 212a and 212b and passing duct 213 are provided on the left side of main body duct 210. On the other hand, in intake unit 211 located to the right of the center of image forming apparatus 100, development intake fans 215a and 215b and passing duct 215 are provided on the right side of main body duct 214.

[0064] The airflow of the intake unit 212 is similar to that of the right intake unit 126 described above, and the airflow of the intake unit 211 is similar to that of the left intake unit 124 described above, so a description thereof will be omitted here. The airflow from these intake units 211 and 212 to the developing devices 1a to 1d is also similar to that of the left intake unit 124 and right intake unit 126 described above, so a description thereof will be omitted.

[0065] In the above-described embodiment, the two air intakes are formed on the front and right side of the image forming apparatus 100 (see FIGS. 3(a) and 3(b)) and on the front and left side of the image forming apparatus 100 (see FIG. 11), but this is not limiting. For example, both air intakes may be formed on the front of the image forming apparatus 100. In this case, however, one air intake is formed to the left of the center on the front of the image forming apparatus 100, and the other air intake is formed to the right of the center on the front of the image forming apparatus 100. Alternatively, both air intakes may be formed on the left and right sides of the image forming apparatus 100.

[0066] In the above-described embodiment, an example was shown in which four image forming units Pa, Pb, Pc, and Pd were arranged in a row along the movement direction of intermediate transfer belt 130, but the number of image forming units is not limited to this and may be, for example, five or more. In this case, the image forming units are divided into a device that blows outside air sucked in by left air intake unit 124 (air intake unit 211) and a device that sends outside air sucked in by right air intake unit 126 (air intake unit 212) with respect to the center of image forming apparatus 100 as described above. Two air intakes are then formed at the above-described positions, respectively.

[0067] In the above embodiment, a sirocco fan is used as the intake fan, but the present invention is not limited to this. An axial flow fan may also be used as the intake fan. [Explanation of symbols]

[0068] 1a (1b)...first developing unit (developing device), 1c (1d)...second developing unit (developing device), 2a (2b)...first charging unit (charging device), 2c (2d)...second charging unit (charging device), 3a (3b)...first photosensitive member (photosensitive drum), 3c (3d)...second photosensitive member (photosensitive drum), 100...image forming apparatus, 101a...casing (first housing), 101b...another housing (second housing), 124...first intake unit (left intake unit), 125...inner cover unit, 126...second intake unit (right Intake unit), 170a, 170b...opening cover (left front door, right front door), 171...exterior cover (intake cover), 171a...first intake port (intake port), 172a...second intake port (intake port), 180a (180b)...first fan (intake fan for development, intake fan for charging), 180c (180d)...second fan (intake fan for development, intake fan for charging), 183a (183b)...first relay duct (flexible tube), 183c (183d)...second relay duct (flexible tube), S...recording material

Claims

1. An image forming apparatus for forming an image on a recording material, The housing and a plurality of image forming units arranged along a first direction, the image forming units including at least a first image forming unit having a first photosensitive member and a first developing unit, and a second image forming unit having a second photosensitive member and a second developing unit; a first intake unit having a first fan that draws in outside air from a first intake port and sends the drawn outside air to the first developing unit; a second intake unit having a second fan that draws in outside air from a second intake port and sends the drawn outside air to the second developing unit; the first image forming unit is disposed at a position closest to a first end of the housing among the plurality of image forming units in the first direction; the second image forming unit is disposed at a position among the plurality of image forming units closest to a second end of the housing opposite to the first end in the first direction; In the first direction, a distance from the first end to the first fan is shorter than a distance from the first end to the first image forming unit, and a distance from the first end to the first air intake port is shorter than a distance from the first end to the second image forming unit, In the first direction, a distance from the second end to the second fan is shorter than a distance from the second end to the second image forming unit, and a distance from the second end to the second air intake port is shorter than a distance from the second end to the first image forming unit, the housing is connected to another housing on the side of the first end in the first direction so as to be able to deliver a recording material; the first air intake port is formed in a second surface intersecting the first surface facing the other housing, the second air intake port is formed in a third surface on a side of the second end facing the first surface in the first direction. An image forming apparatus characterized by:

2. An image forming apparatus for forming an image on a recording material, The housing and a plurality of image forming units arranged along a first direction, the image forming units including at least a first image forming unit having a first photosensitive member and a first developing unit, and a second image forming unit having a second photosensitive member and a second developing unit; a first intake unit having a first fan that draws in outside air from a first intake port and sends the drawn outside air to the first developing unit; a second intake unit having a second fan that draws in outside air from a second intake port and sends the drawn outside air to the second developing unit; the first image forming unit is disposed at a position closest to a first end of the housing among the plurality of image forming units in the first direction; the second image forming unit is disposed at a position among the plurality of image forming units closest to a second end of the housing opposite to the first end in the first direction; In the first direction, a distance from the first end to the first fan is shorter than a distance from the first end to the first image forming unit, and a distance from the first end to the first air intake port is shorter than a distance from the first end to the second image forming unit, In the first direction, a distance from the second end to the second fan is shorter than a distance from the second end to the second image forming unit, and a distance from the second end to the second air intake port is shorter than a distance from the second end to the first image forming unit, The housing has four support columns arranged on four sides, the first air intake unit and the second air intake unit are supported by the front-side and rear-side pillars such that the first fan and the second fan are located rearward of the two front-side pillars among the pillars; An image forming apparatus characterized by:

3. An image forming apparatus for forming an image on a recording material, The housing and a plurality of image forming units arranged along a first direction, the image forming units including at least a first image forming unit having a first photosensitive member and a first developing unit, and a second image forming unit having a second photosensitive member and a second developing unit; a first intake unit having a first fan that draws in outside air from a first intake port and sends the drawn outside air to the first developing unit; a second air intake unit having a second fan that draws in outside air from a second air intake port and sends the drawn outside air to the second developing unit; an openable / closable cover provided on the front surface of the housing; an inner cover unit disposed on the housing so as to face the inner surface of the opening / closing cover in a closed state; the first image forming unit is disposed at a position closest to a first end of the housing among the plurality of image forming units in the first direction; the second image forming unit is disposed at a position among the plurality of image forming units closest to a second end of the housing opposite to the first end in the first direction; In the first direction, a distance from the first end to the first fan is shorter than a distance from the first end to the first image forming unit, and a distance from the first end to the first air intake port is shorter than a distance from the first end to the second image forming unit, In the first direction, a distance from the second end to the second fan is shorter than a distance from the second end to the second image forming unit, and a distance from the second end to the second air intake port is shorter than a distance from the second end to the first image forming unit, the inner cover unit has a first relay duct connected to the first air intake unit to guide the outside air drawn in by the first fan toward the first developing unit, and a second relay duct connected to the second air intake unit to guide the outside air drawn in by the second fan toward the second developing unit. An image forming apparatus characterized by:

4. The housing has another housing connected to the side of the first end in the first direction so that a recording material can be delivered, the first air intake port is formed in a second surface intersecting the first surface facing the other housing, the second air intake port is formed in a third surface on a side of the second end facing the first surface in the first direction.

4. The image forming apparatus according to claim 2, wherein the image forming apparatus is a recording medium.

5. The housing has four support pillars arranged on all four sides, the first air intake unit and the second air intake unit are supported by the front-side and rear-side pillars such that the first fan and the second fan are located rearward of the two front-side pillars among the pillars; 4. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

6. An opening / closing cover provided on the front of the housing in an openable / closable manner; an inner cover unit disposed on the housing so as to face the inner surface of the opening / closing cover in a closed state; the inner cover unit has a first relay duct connected to the first air intake unit to guide the outside air drawn in by the first fan toward the first developing unit, and a second relay duct connected to the second air intake unit to guide the outside air drawn in by the second fan toward the second developing unit.

3. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

7. An opening / closing cover provided on the front of the housing in an openable / closable manner; an inner cover unit disposed on the housing so as to face the inner surface of the opening / closing cover in a closed state; the inner cover unit has a first relay duct connected to the first air intake unit and guiding the outside air drawn in by the first fan toward the first developing unit, and a second relay duct connected to the second air intake unit and guiding the outside air drawn in by the second fan toward the second developing unit, The housing has four support columns arranged on four sides, the first air intake unit and the second air intake unit are supported by the front-side and rear-side pillars such that the first fan and the second fan are located rearward of the two front-side pillars among the pillars; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

8. An exterior cover provided on the front of the housing, The first air intake port is formed in the exterior cover.

8. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

9. An image forming apparatus for forming an image on a recording material, comprising: The housing and a plurality of image forming units arranged along a first direction, the image forming units including at least a first image forming unit having a first photosensitive member and a first charging unit, and a second image forming unit having a second photosensitive member and a second charging unit; a first intake unit having a first fan that draws in outside air through a first intake port and sends the drawn outside air to the first charging unit; a second air intake unit having a second fan that draws in outside air from a second air intake port and sends the drawn outside air to the second charging unit, the first image forming unit is disposed at a position closest to a first end of the housing among the plurality of image forming units in the first direction; the second image forming unit is disposed at a position among the plurality of image forming units closest to a second end of the housing opposite to the first end in the first direction; In the first direction, a distance from the first end to the first fan is shorter than a distance from the first end to the first image forming unit, and a distance from the first end to the first air intake port is shorter than a distance from the first end to the second image forming unit, In the first direction, a distance from the second end to the second fan is shorter than a distance from the second end to the second image forming unit, and a distance from the second end to the second air intake port is shorter than a distance from the second end to the first image forming unit, the housing is connected to another housing on the side of the first end in the first direction so as to be able to deliver a recording material; the first air intake port is formed in a second surface intersecting the first surface facing the other housing, the second air intake port is formed in a third surface on a side of the second end facing the first surface in the first direction. An image forming apparatus characterized by:

10. An image forming apparatus for forming an image on a recording material, comprising: The housing and a plurality of image forming units arranged along a first direction, the image forming units including at least a first image forming unit having a first photosensitive member and a first charging unit, and a second image forming unit having a second photosensitive member and a second charging unit; a first intake unit having a first fan that draws in outside air through a first intake port and sends the drawn outside air to the first charging unit; a second air intake unit having a second fan that draws in outside air from a second air intake port and sends the drawn outside air to the second charging unit, the first image forming unit is disposed at a position closest to a first end of the housing among the plurality of image forming units in the first direction; the second image forming unit is disposed at a position among the plurality of image forming units closest to a second end of the housing opposite to the first end in the first direction; In the first direction, a distance from the first end to the first fan is shorter than a distance from the first end to the first image forming unit, and a distance from the first end to the first air intake port is shorter than a distance from the first end to the second image forming unit, In the first direction, a distance from the second end to the second fan is shorter than a distance from the second end to the second image forming unit, and a distance from the second end to the second air intake port is shorter than a distance from the second end to the first image forming unit, The housing has four support columns arranged on four sides, the first air intake unit and the second air intake unit are supported by the front-side and rear-side pillars such that the first fan and the second fan are located rearward of the two front-side pillars among the pillars; An image forming apparatus characterized by:

11. An image forming apparatus for forming an image on a recording material, comprising: The housing and a plurality of image forming units arranged along a first direction, the image forming units including at least a first image forming unit having a first photosensitive member and a first charging unit, and a second image forming unit having a second photosensitive member and a second charging unit; a first intake unit having a first fan that draws in outside air through a first intake port and sends the drawn outside air to the first charging unit; a second air intake unit having a second fan that draws in outside air from a second air intake port and sends the drawn outside air to the second charging unit; an openable / closable cover provided on the front surface of the housing; an inner cover unit disposed on the housing so as to face the inner surface of the opening / closing cover in a closed state; the first image forming unit is disposed at a position closest to a first end of the housing among the plurality of image forming units in the first direction; the second image forming unit is disposed at a position among the plurality of image forming units closest to a second end of the housing opposite to the first end in the first direction; In the first direction, a distance from the first end to the first fan is shorter than a distance from the first end to the first image forming unit, and a distance from the first end to the first air intake port is shorter than a distance from the first end to the second image forming unit, In the first direction, a distance from the second end to the second fan is shorter than a distance from the second end to the second image forming unit, and a distance from the second end to the second air intake port is shorter than a distance from the second end to the first image forming unit, The inner cover unit has a first relay duct connected to the first air intake unit and guiding the outside air drawn in by the first fan toward the first charging unit, and a second relay duct connected to the second air intake unit and guiding the outside air drawn in by the second fan toward the second charging unit. An image forming apparatus characterized by:

12. The housing has another housing connected to the first end side in the first direction so as to be able to transfer a recording material, the first air intake port is formed in a second surface intersecting the first surface facing the other housing, the second air intake port is formed in a third surface on a side of the second end facing the first surface in the first direction.

12. The image forming apparatus according to claim 10, wherein the image forming apparatus is a recording medium.

13. The housing has four support pillars arranged on all four sides, the first air intake unit and the second air intake unit are supported by the front-side and rear-side pillars such that the first fan and the second fan are located rearward of the two front-side pillars among the pillars; 12. The image forming apparatus according to claim 9, wherein the image forming apparatus is a recording medium.

14. An opening / closing cover provided on the front of the housing in an openable / closable manner; an inner cover unit disposed on the housing so as to face the inner surface of the opening / closing cover in a closed state; The inner cover unit has a first relay duct connected to the first air intake unit and guiding the outside air drawn in by the first fan toward the first charging unit, and a second relay duct connected to the second air intake unit and guiding the outside air drawn in by the second fan toward the second charging unit.

11. The image forming apparatus according to claim 9, wherein the image forming apparatus is a recording medium.

15. An opening / closing cover provided on the front of the housing in an openable / closable manner; an inner cover unit disposed on the housing so as to face the inner surface of the opening / closing cover in a closed state; the inner cover unit has a first relay duct connected to the first air intake unit and guiding the outside air drawn in by the first fan toward the first charging unit, and a second relay duct connected to the second air intake unit and guiding the outside air drawn in by the second fan toward the second charging unit, The housing has four support columns arranged on four sides, the first air intake unit and the second air intake unit are supported by the front-side and rear-side pillars such that the first fan and the second fan are located rearward of the two front-side pillars among the pillars; 10. The image forming apparatus according to claim 9,

16. An exterior cover provided on the front of the housing, The first air intake port is formed in the exterior cover.

16. The image forming apparatus according to claim 9, wherein the image forming apparatus is a recording medium.

Images