Image forming apparatus

Abstract

An image forming apparatus capable of suppressing the inflow of water vapor-containing exhaust gas into a processing unit includes: a main body housing having louvers; a processing unit including a photosensitive drum and a developer for forming a toner image on a sheet; a fuser for heating and fixing the sheet on which the toner image is formed; an exhaust fan for discharging air from the main body housing, not overlapping the processing unit in the axial direction of the photosensitive drum and being closer to the inside of the main body housing than the louvers in the axial direction; a first conduit having an end closer to the louvers in the axial direction than the exhaust fan, for accommodating the exhaust fan; a filter disposed between the louvers and the end of the first conduit in the axial direction; and a seal made of an elastomer surrounding the periphery of the exhaust fan in a state of being sandwiched between the end of the first conduit and the filter in the axial direction, sealing the center between the processing unit and the exhaust fan in the axial direction, and having an opening in the axial direction on the opposite side of the processing unit located at the center of the exhaust fan.

Description

Technical Field

[0001] This invention relates to an image forming apparatus. Background Technology

[0002] Previously, as disclosed in Patent Document 1, an image forming apparatus was known, including a processing unit for forming a toner image on a sheet, a fan for discharging air from the apparatus body, a pipe for guiding exhaust from the fan to an exhaust port formed on an outer part of the apparatus body, and a filter disposed downstream of the fan in the exhaust direction, through which dust and the like in the air discharged by the fan are removed.

[0003] In the image forming apparatus disclosed in Patent Document 1, a filter is clamped and held between a pipe and an external component.

[0004] Patent Document 1: Japanese Patent Application Publication No. 7-134522 Summary of the Invention

[0005] In the image forming apparatus disclosed in Patent Document 1, a load is applied to the filter in a structure that clamps the filter between the pipe and the external component. To reduce the load applied to the filter, an elastic member is considered to be provided between the filter and the pipe. However, with the elastic member provided, the flow resistance caused by the filter increases, resulting in reduced exhaust efficiency and sometimes excessive positive pressure between the fan and the filter.

[0006] If the positive pressure between the fan and the filter is too high, air containing water vapor generated from the fuser may leak out, and the water vapor may flow into the processing section.

[0007] Therefore, in this invention, an image forming apparatus is provided to suppress the inflow of exhaust gas containing water vapor into the processing unit.

[0008] To solve the above problems, the image forming apparatus of the present invention has the following features.

[0009] That is, the present invention provides an image forming apparatus, comprising: a body housing having louvers; a processing unit including a photosensitive drum rotating about an axis and a developer supplying toner to the photosensitive drum for forming a toner image on a sheet; a fixing unit for heating and fixing the sheet on which the toner image has been formed; an exhaust fan for exhausting air from the body housing, disposed at a position that does not overlap with the processing unit when viewed from the axial direction of the photosensitive drum and is closer to the inner side of the body housing than the louvers in the axial direction; and a first conduit having a duct in the axial direction. An exhaust fan is housed within the interior space of the first duct, positioned closer to the end of the louver than the exhaust fan itself; a filter is disposed in the axial direction between the louver and the end of the first duct; and a seal, made of an elastomer, surrounds the periphery of the exhaust fan in a manner sandwiched between the end of the first duct and the filter in the axial direction, sealing the center of the exhaust fan from the processing section as viewed from the axial direction, and having an opening on the opposite side of the processing section located at the center of the exhaust fan as viewed from the axial direction.

[0010] Therefore, the sealing element reduces the load on the filter and improves the airtightness of the first duct. Furthermore, when the positive pressure between the filter and the exhaust fan is too high, air can be discharged through the opening to the side opposite to the processing section, thus preventing water vapor-containing air from flowing into the processing section.

[0011] Additionally, viewed from the axial direction, the exhaust fan is located above the fuser.

[0012] Therefore, the air heated by the fuser can be exhausted to the outside of the main body housing by the exhaust fan.

[0013] Furthermore, viewed from the axial direction, the exhaust fan is disposed below the fuser, and the image forming apparatus has a first substrate disposed at a position overlapping with the exhaust fan when viewed from the axial direction.

[0014] Therefore, the heat generated on the first substrate can be discharged to the outside of the main body housing by the exhaust fan.

[0015] Additionally, the seal has an opening located below the exhaust fan.

[0016] This allows liquid that has entered the main body casing to be discharged to the outside of the main body casing through the opening below the exhaust fan.

[0017] Additionally, the image forming apparatus includes a grounding component that contacts the filter to ground it, the grounding component being disposed in the portion of the first conduit that overlaps with the opening of the seal in the axial direction.

[0018] Therefore, the filter can be grounded through the grounding component, and pressure can be applied to the filter at the opening portion of the seal.

[0019] Additionally, the processing unit has a developing roller, the main body housing has a first side surface located at one end in the axial direction, the exhaust fan is located within the main body housing and is closer to the first side surface in the axial direction than the center of the main body housing, and the image forming apparatus has a second substrate for applying a developing bias to the developing roller, the second substrate being located within the main body housing and is closer to the first side surface in the axial direction than the center of the main body housing, and is positioned to overlap with the processing unit but not with the exhaust fan when viewed from the axial direction.

[0020] Therefore, by having a seal between the exhaust fan and the second substrate, it is possible to suppress the flow of exhaust gas from the exhaust fan toward the second substrate side.

[0021] In addition, the seal is made of sponge.

[0022] This reduces the load applied to the filter and improves the seal between the filter and the first pipe.

[0023] Additionally, the image forming apparatus includes: an intake fan for drawing air into the main housing; and a second conduit for guiding the air intake from the intake fan along the axial direction to the processing unit.

[0024] Therefore, by using the suction pipe to guide the suction of the suction fan to the processing section, it is possible to suppress excessive negative pressure in the processing section and suppress the exhaust flow generated by the exhaust fan to the processing section side.

[0025] In addition, the processing unit has an electrical charge for charging the photosensitive drum, and the filter is an ozone filter capable of decomposing ozone in the passing air.

[0026] This allows for the suppression of ozone generated inside the casing from escaping to the outside of the casing.

[0027] According to the present invention, it is possible to suppress the inflow of air containing water vapor into the treatment unit. Attached Figure Description

[0028] Figure 1 This is a central cross-sectional view showing the image forming apparatus.

[0029] Figure 2 This is a perspective view showing the image forming apparatus.

[0030] Figure 3 This is a side view showing the right side wall of the main body housing.

[0031] Figure 4 This is an exploded perspective view showing the fan and exhaust filter supported on the right frame.

[0032] Figure 5 It is a rear sectional view showing the fan duct, exhaust fan, exhaust filter, and louvers.

[0033] Figure 6 This is a side view showing the control board supported on the right frame and the seals surrounding the exhaust fan.

[0034] Figure 7 This is a side view showing the first exhaust fan, the first fan duct, the seal, and the grounding spring.

[0035] Figure 8 This is a rear sectional view showing a grounding spring supported on the rear wall of the first fan duct.

[0036] Figure 9 This is a three-dimensional diagram showing the grounding spring.

[0037] Figure 10 It is a side view showing an intake fan supported on the right frame, an intake duct formed on the right frame, and a seal surrounding the outer periphery of the exhaust fan. Detailed Implementation

[0038] The following description uses the accompanying drawings to illustrate the methods for carrying out the present invention.

[0039] [Image forming apparatus]

[0040] Figure 1 , Figure 2 The image forming apparatus 1 shown is an embodiment of the image forming apparatus of the present invention, which is a color laser printer that forms multi-color images on a sheet S by means of electrophotography.

[0041] In the following explanation, Figure 1 The left side is defined as the front side of the image forming apparatus 1, and will Figure 1 The right side of the image forming apparatus 1 is defined as the rear side. Figure 1 The front side of the paper in the image is defined as the right side of the image forming apparatus 1. Figure 1 The paper depth side is defined as the left side of the image forming apparatus 1. Additionally, Figure 1 The upper and lower sides are defined as the upper and lower sides of the image forming apparatus 1, respectively.

[0042] The image forming apparatus 1 includes a main housing 2, a sheet supply section 3 having a sheet tray 10 for supporting a sheet S and a sheet transport section 30 for transporting the sheet S, and an image forming section 5 for forming an image on the sheet S transported by the sheet supply section 3.

[0043] The main body housing 2 is formed in a generally rectangular shape to house the sheet supply section 3 and the image forming section 5. A front opening 2A is provided on the front surface of the main body housing 2, and the main body housing 2 has a front cover 21 that can open and close the front opening 2A.

[0044] The front cover 21 is configured to rotate around the rotation shaft 21a at the lower end. By rotating around the rotation shaft 21a, it can move between the closed position of the front opening 2A and the open position of the front opening 2A.

[0045] A top cover 22 is disposed on the upper surface of the main body housing 2, and the top cover 22 has a discharge plate 221 that tilts downward from the front to the rear.

[0046] The sheet supply unit 3 is located at the lower part of the main body housing 2, and the sheet S supported on the sheet tray 10 is transported to the image forming unit 5 by the sheet conveying unit 30. The sheet tray 10 is configured to slide in the forward and backward direction and to move between a receiving position in the main body housing 2 and a separation position pulled forward from the receiving position.

[0047] The sheet conveying unit 30 includes a feed roller 32, a separation roller 33, a separation pad 33a, a conveying roller pair 34, and a positioning roller pair 35. Within the main body housing 2, a conveying path P is formed for the sheet S to travel from the sheet tray 10 through the image forming unit 5 to the discharge tray 221.

[0048] The sheets S supported on the sheet tray 10 are separated one by one by the feed roller 32, the separation roller 33, and the separation pad 33a, and conveyed to the transport path P. The feed roller 32 is a roller that conveys the sheets S from the sheet tray 10 to the image forming unit 5. The separation roller 33 and the separation pad 33a constitute a separation device for separating the sheets S supported by the sheet tray 10 one by one.

[0049] The sheet S, conveyed to the conveying path P, is transported to the image forming unit 5 via the conveying roller pair 34 and the positioning roller pair 35. The positioning roller pair 35 restricts the movement of the head end of the conveyed sheet S, thereby temporarily stopping it, and then, at a predetermined time, the sheet S is transported to the image forming unit 5.

[0050] The image forming unit 5 is positioned above the film supply unit 3 and includes four processing cartridges 50 arranged in a front-to-back direction and a photosensitive drum 51 corresponding to each processing cartridge 50. Each processing cartridge 50 contains toners for yellow, magenta, cyan, and black, respectively. The processing cartridges 50 are arranged from front to back in the order of yellow, magenta, cyan, and black. Each processing cartridge 50 includes a developing roller 52.

[0051] The processing box 50 is supported on the drawer 59 in a removable manner. By opening the front cover 21, the drawer 59 can be pulled out of the main body housing 2 through the front opening 2A in the main body housing 2. The drawer 59 is movable between a first position disposed inside the main body housing 2 and a second position at least partially disposed outside the main body housing 2.

[0052] The photosensitive drum 51 is formed into a generally cylindrical shape with its axis running horizontally. The photosensitive drum 51 is supported on the drawer 59 and can rotate about an axis extending horizontally. That is, the photosensitive drum 51 rotates around an axis. The horizontal direction is an example of the axial direction.

[0053] The developing roller 52 extends in the left-right direction and is supported by the processing cartridge 50 in a rotatable manner. Toner is an example of a developer. The developing roller 52 of the processing cartridge 50 supplies toner to the photosensitive drum 51. The processing cartridge 50 is an example of a developer that supplies toner to the photosensitive drum.

[0054] The housing 2 includes an exposure device 56 for exposing the surface of the photosensitive drum 51. The exposure device 56 includes a laser diode (not shown), a polarizer, a lens, and a reflector. The exposure device 56 emits a light beam to each photosensitive drum 51, exposing the surface of each photosensitive drum 51.

[0055] The transfer belt 41 is positioned below and opposite the photosensitive drum 51 along the conveying path P. The transfer belt 41 contacts the photosensitive drum 51. The transfer belt 41 is supported between the drive roller 42 and the driven roller 43 positioned in front of the drive roller 42. Transfer rollers 44 are positioned at positions that clamp the transfer belt 41 and are opposite to each photosensitive drum 51. In the image forming unit 5, a belt unit 40 is constituted by the transfer belt 41, the drive roller 42, the driven roller 43, and the transfer rollers 44.

[0056] The image forming unit 5 includes a charge carrier 54 for charging each photosensitive drum 51. The charge carrier 54 is supported by a drawer 59. The photosensitive drums 51, which are uniformly charged by the charge carrier 54, are selectively exposed by the exposure apparatus 56. Through exposure, the charge is selectively removed from the surface of the photosensitive drum 51, and an electrostatic latent image is formed on the surface of the photosensitive drum 51.

[0057] The toner contained in the processing cartridge 50 is positively charged and carried on the surface of the developing roller 52. A developing bias voltage is applied to the developing roller 52. When the electrostatic latent image formed on the photosensitive drum 51 is opposite to the developing roller 52, toner is supplied from the developing roller 52 to the electrostatic latent image through the potential difference between the electrostatic latent image and the developing roller 52. Thus, a toner image is formed on the surface of the photosensitive drum 51.

[0058] When the sheet S being conveyed to the image forming unit 5 reaches above the transfer belt 41, it is conveyed by the transfer belt 41 and passes sequentially between the transfer belt 41 and each photosensitive drum 51. When the toner image carried on the surface of the photosensitive drum 51 is opposite to the sheet S, the toner image is transferred onto the sheet S by applying a transfer bias voltage to the transfer roller 44.

[0059] In this embodiment, the transfer belt 41 is a conveyor belt that transports the sheet S on which the toner image has been transferred. However, the transfer belt may also be configured as an intermediate transfer belt that transfers the toner image onto the belt itself and then transfers the toner image transferred onto the belt onto the sheet S.

[0060] A sheet S with a toner image transferred onto it is fed to a fuser 60. The fuser 60 has a heating roller 61 and a pressure roller 62 pressed against the heating roller 61. During the passage of the sheet S fed to the fuser 60 between the heating roller 61 and the pressure roller 62, the toner image is thermally fixed. That is, the fuser 60 heats and fixes the sheet S with the toner image.

[0061] The toner image is heat-fixed on the sheet S, which is then conveyed from the fuser 60 to the downstream side of the conveying direction. It is then conveyed by the intermediate discharge roller pair 63 and the discharge roller pair 64 disposed on the downstream side of the conveying direction of the intermediate discharge roller pair 63, and discharged onto the discharge tray 221.

[0062] In the image forming apparatus 1, a processing unit PU is constituted by a drawer 59, a processing box 50 supported by the drawer 59, a photosensitive drum 51, and a belt capacitor 54 for forming a toner image on a sheet S. The processing unit PU is an example of a processing section for forming a toner image on a sheet.

[0063] The processing unit PU only needs to have at least a photosensitive drum 51 and a processing cartridge 50, and may also include a transfer belt 41 or a fuser 60. In the processing unit PU, the photosensitive drum 51 may be supported by a drawer 59 as described in this embodiment, or the photosensitive drum 51 may be supported by the processing cartridge 50.

[0064] The image forming apparatus 1 includes a power supply substrate 11 on which power supply circuitry is formed and a substrate cover 12 covering the power supply substrate 11. The power supply substrate 11 is an example of a first substrate. The substrate cover 12 is disposed at the rear of the body housing 2, between the sheet tray 10 and the tape unit 40. The substrate cover 12 is located below the fuser 60. The body housing 2 houses the processing unit PU and the substrate cover 12.

[0065] The image forming apparatus 1 includes a first exhaust fan 71 and a second exhaust fan 72, which exhaust air inside the body housing 2 to the outside of the body housing 2. The first exhaust fan 71 and the second exhaust fan 72 are examples of exhaust fans used to exhaust air from inside the body housing 2.

[0066] The first exhaust fan 71 is located to the right and rear of the processing unit PU inside the main housing 2, and exhausts the air that has passed through the processing unit PU and the fuser 60 inside the main housing 2 to the outside of the main housing 2. Thus, the first exhaust fan 71 can effectively exhaust the air that has passed through the processing unit PU and the fuser 60.

[0067] The first exhaust fan 71 is positioned so as not to overlap with the processing unit PU when viewed from the left and right. Furthermore, when viewed from the left and right, the first exhaust fan 71 is located above the fuser 60. By positioning the first exhaust fan 71 above the fuser 60, the air heated by the fuser 60 inside the main body housing 2 can be effectively exhausted to the outside of the main body housing 2.

[0068] The second exhaust fan 72 is disposed to the right of the substrate cover 12 and the power supply board 11 inside the main body housing 2. Viewed from the left and right, the second exhaust fan 72 is positioned overlapping the substrate cover 12 and the power supply board 11. The second exhaust fan 72 is located below the first exhaust fan 71. The second exhaust fan 72 is configured to exhaust air from inside the substrate cover 12 inside the main body housing 2 to the outside of the main body housing 2.

[0069] The second exhaust fan 72 is positioned so as not to overlap with the processing unit PU when viewed from the left and right. Viewed from the left and right, the second exhaust fan 72 is located below the fuser 60. By positioning the second exhaust fan 72 below the fuser 60 and overlapping with the power supply board 11, heat generated in the power supply board 11 can be effectively exhausted to the outside of the main body housing 2 via the second exhaust fan 72.

[0070] like Figure 2As shown, a right frame 26 is accommodated at the right end of the main body housing 2, and the main body housing 2 has a right side wall 23 covering the right side of the right frame 26. The right side wall 23 is located on the right end side in the left-right direction of the main body housing 2. The right side surface of the right side wall 23 is an example of a first side surface located on one end side in the axial direction.

[0071] The right side wall 23 has a first opening 23a and a second opening 23b that extend through the right side wall 23 in the left-right direction. The first opening 23a and the second opening 23b are located at the rear of the right side wall 23, with the first opening 23a located above the second opening 23b.

[0072] The first exhaust fan 71 is supported by the right frame 26, and when viewed from the left and right, the first exhaust fan 71 is positioned overlapping with the first opening 23a. By driving the first exhaust fan 71, an airflow is generated from left to right. Through the airflow generated by the first exhaust fan 71, air inside the processing unit PU and air near the fuser 60 are discharged to the outside of the main body housing 2 through the first opening 23a. The right side wall 23 is positioned downstream of the first exhaust fan 71 in the exhaust direction of the first exhaust fan 71.

[0073] The second exhaust fan 72 is supported by the right frame 26 and is positioned overlapping the second opening 23b when viewed from the left-right direction. Driving the second exhaust fan 72 generates an airflow from left to right, through which air within the substrate cover 12 is discharged to the outside of the main body housing 2 via the second opening 23b. The right side wall 23 is positioned downstream of the second exhaust fan 72 in the exhaust direction of the second exhaust fan 72.

[0074] The first exhaust fan 71 and the second exhaust fan 72 are located on the right side wall 23 inside the main body housing 2 in the left-right direction. Here, "right side wall 23 inside the main body housing 2" means the right side of the right side wall 23 that is closer to the center of the main body housing 2 in the left-right direction. That is, the first exhaust fan 71 and the second exhaust fan 72 are located on the first side side in the axial direction inside the main body housing.

[0075] The right side wall 23 has an air intake 23c that extends through the right side wall 23 in the left-right direction. Air from outside the main body housing 2 can flow into the main body housing 2 through the air intake 23c. The image forming apparatus 1 has an air intake fan 77 disposed inside the right side wall 23 to draw air from outside the main body housing 2 into the main body housing 2. The air intake fan 77 is disposed at the right end and lower front part inside the main body housing 2.

[0076] By driving the intake fan 77, air from outside the main body housing 2 is drawn into the interior of the main body housing 2 through the intake port 23c. By cooling the interior of the main body housing 2 with the air drawn in, the temperature rise inside the main body housing 2 can be suppressed.

[0077] A control board 13 capable of controlling the operation of the image forming apparatus 1 is supported on the right side of the right frame 26. The control board 13 is a high-voltage power supply board capable of applying high voltage. The control board 13 can apply a developing bias voltage to the developing roller 52, a charging bias voltage to the belt conveyor 54, and a transfer bias voltage to the transfer roller 44. The control board 13 is an example of a second board that applies a developing bias voltage to the developing roller.

[0078] The control board 13 is disposed in the left-right direction between the right frame 26 and the right side wall 23, located on the right side wall 23 inside the main body housing 2. That is, the control board 13 is located on the first side side in the axial direction inside the main body housing.

[0079] The control board 13 is located in front of the first exhaust fan 71 and the second exhaust fan 72 in the front-back direction. Viewed from the left-right direction, the control board 13 is positioned so as not to overlap with the first exhaust fan 71 and the second exhaust fan 72. Viewed from the left-right direction, the control board 13 is positioned to overlap with the processing unit PU.

[0080] [First exhaust fan, first fan duct, first exhaust filter, and first louver]

[0081] like Figures 2 to 5 As shown, the right frame 26 has a first fan duct 27 extending in the left-right direction. The first fan duct 27 is an example of a first duct. The first fan duct 27 extends in the left-right direction, allowing air to flow in that direction. The first fan duct 27 is formed to be quadrilateral in shape when viewed from the left-right direction. A first exhaust fan 71 is fitted into the first fan duct 27. The first fan duct 27 accommodates the first exhaust fan 71.

[0082] The right side wall 23 of the main body housing 2 has a first louver 24 covering the first opening 23a. The first louver 24 is an example of a louver. The first louver 24 connects the interior and exterior of the main body housing 2. In this embodiment, the first louver 24 is formed integrally with the right side wall 23, but it can also be a structure in which the first louver 24 is mounted on the right side wall 23 in a detachable manner.

[0083] The first louver 24 is located to the right of the first fan duct 27 and the first exhaust fan 71. That is, the first fan duct 27 and the first exhaust fan 71 are arranged in the left-right direction on the inner side of the main body housing 2, which is closer to the inside of the main body housing 2 than the first louver 24.

[0084] The first louver 24 has a frame 240 formed into a quadrilateral along the periphery of the exhaust port 23a, and a plurality of blades 241 disposed within the area surrounded by the frame 240. The blades 241 extend in the front-to-back direction and are arranged in a plurality in the up-down direction. The blades 241 tilt upward from left to right, and the air flowing from left to right is redirected to a rightward and upward direction by passing through the first louver 24.

[0085] The first fan duct 27 protrudes further to the right than the first exhaust fan 71. That is, the right end 27F of the first fan duct 27 extends in the left-right direction between the first exhaust fan 71 and the first louver 24. In other words, in the left-right direction, the right end 27F of the first fan duct 27 is closer to the first louver 24 than the first exhaust fan 71.

[0086] The image forming apparatus 1 has a first exhaust filter 73, which is located in the left-right direction between a first louver 24, a first fan duct 27, and a first exhaust fan 71. The first exhaust filter 73 is supported on the right side wall 23. The first exhaust filter 73 is an example of a filter. The first exhaust filter 73 is formed into a quadrilateral shape when viewed from the left-right direction.

[0087] The first exhaust filter 73 has a right-side surface, namely a first surface 73a, and a left-side surface, namely a second surface 73b. The first surface 73a is opposite to the first louver 24 of the right side wall 23, and the second surface 73b is opposite to the first fan duct 27 and the first exhaust fan 71.

[0088] The first exhaust filter 73 is, for example, a honeycomb filter in which the filter material is formed into a honeycomb shape. The honeycomb filter constituting the first exhaust filter 73 has a plurality of pores separated by partitions extending in the left-right direction.

[0089] The filter material constituting the first exhaust filter 73 can be, for example, paper, aluminum, or other metals or ceramics that carry ozone decomposition catalysts such as manganese dioxide or activated carbon. The first exhaust filter 73 is formed in the shape of a rectangular sheet.

[0090] Inside the main housing 2, components such as the electrical charge 54 of the processing unit PU that discharge in the atmosphere can generate ozone. Additionally, toner contained in the processing box 50 may sometimes float within the main housing 2.

[0091] Air inside the processing unit PU is drawn to the rear of the processing unit PU by the first exhaust fan 71 and then flows to the right, passing through the first exhaust filter 73. Dust such as toner is removed from the air that has passed through the first exhaust filter 73, and the air is discharged to the outside of the main body housing 2 through the first louver 24. Therefore, it is possible to reduce the amount of dust and other particles contained in the air discharged by the first exhaust fan 71 that has passed through the processing unit PU.

[0092] The first exhaust filter 73 can be any filter capable of removing dust such as toner from the air. In addition to capturing and removing dust such as toner, an ozone filter capable of decomposing ozone in the air can also be used as the first exhaust filter 73.

[0093] By constructing the first exhaust filter 73 with an ozone filter capable of decomposing ozone in the passing air, the amount of ozone contained in the exhaust gas discharged by the first exhaust fan 71 can be reduced. This prevents the ozone generated inside the main body housing 2 from being emitted to the outside of the main body housing 2.

[0094] like Figures 4 to 6 As shown, the first exhaust fan 71 includes a rotating shaft 711 extending in the left-right direction, blades 712 fixed on the rotating shaft 711, and a housing 713 that supports the rotating shaft 711 in a rotatable manner. It is an axial flow fan that delivers air along the axial direction of the rotating shaft 711. The housing 713 of the first exhaust fan 71 is quadrilateral in shape.

[0095] The housing 713 is shaped to form the shape of the first exhaust fan 71. The housing 713 protrudes further to the right than the blade 712. That is, the right end of the housing 713 extends in the left-right direction between the blade 712 and the first louver 24. In other words, in the left-right direction, the right end of the housing 713 is closer to the first louver 24 than the blade 712.

[0096] like Figures 5 to 7 As shown, the first fan duct 27 includes an upper duct wall 27A located above the first exhaust fan 71, a front duct wall 27B located in front of the first exhaust fan 71, a rear duct wall 27C located behind the first exhaust fan 71, and a lower duct wall 27D and a bottom duct wall 27E located below the first exhaust fan 71.

[0097] The peripheral wall of the first fan duct 27 is formed by an upper wall 27A, a front wall 27B, a rear wall 27C, and a lower wall 27D. The upper wall 27A, the front wall 27B, the rear wall 27C, and the lower wall 27D support the first exhaust fan 71 housed within the first fan duct 27. The peripheral wall of the first fan duct 27 covers the outer periphery of the first exhaust fan 71.

[0098] The bottom wall 27E of the pipe is formed in the middle of the front-rear direction of the lower wall 27D of the pipe, and is located in a position that is recessed further downward than the lower wall 27D of the pipe. The bottom wall 27E of the pipe extends in the left-right direction. Liquid that has entered the interior of the main body housing 2 from above is collected in the bottom wall 27E of the pipe and flows to the right along the bottom wall 27E of the pipe. The liquid flowing along the bottom wall 27E of the pipe can be discharged to the outside of the main body housing 2 through the first louver 24.

[0099] A buffer member 78 is disposed between the outer peripheral surface of the housing 713 of the first exhaust fan 71 and the inner peripheral surface of the first fan duct 27. The buffer member 78 closes the gap between the housing 713 of the first exhaust fan 71 and the first fan duct 27. The buffer member 78 is formed of a resilient material, such as a resilient sponge.

[0100] Therefore, by arranging a buffer member 78 between the outer periphery of the first exhaust fan 71 and the inner periphery of the first fan duct 27 to fill the gap between the first exhaust fan 71 and the first fan duct 27, it is possible to prevent air delivered by the first exhaust fan 71 from leaking out between the first exhaust fan 71 and the first fan duct 27.

[0101] [Seals]

[0102] like Figures 5 to 7 As shown, a gap G is formed between the first fan duct 27 and the first exhaust filter 73 in the left-right direction. Specifically, a gap G is formed between the right end 27F of the first fan duct 27 and the first exhaust filter 73 in the left-right direction. A seal 76 is disposed in the gap G between the first fan duct 27 and the first exhaust filter 73 in the left-right direction. Specifically, a seal 76 is disposed in the gap G between the right end 27F of the first fan duct 27 and the first exhaust filter 73 in the left-right direction. The seal 76 is formed using a component made of an elastomer. The seal 76 is, for example, formed of an elastic sponge.

[0103] The seal 76 includes a first seal 761, a second seal 762, and a third seal 763. The first seal 761 is formed in an I-shape extending linearly in the front-rear direction. The second seal 762 is formed in an L-shape by a portion extending in the vertical direction and a portion extending rearward from the lower end of the portion extending in the vertical direction. The third seal 763 is disposed at the rear and lower corner of the first exhaust fan 71 and is formed in a triangular shape.

[0104] The first seal 761 is disposed between the upper wall 27A of the first fan duct 27 and the first exhaust filter 73. The second seal 762 is disposed between the portion of the front wall 27B and the lower wall 27D of the first fan duct 27, which is further forward than the bottom wall 27E, and the first exhaust filter 73. The third seal 763 is disposed between the rear and lower corner of the first exhaust fan 71 and the first exhaust filter 73.

[0105] In this embodiment, the sealing member 76 is formed by dividing it into a first sealing member 761 and a second sealing member 762, but the first sealing member 761 and the second sealing member 762 may also be formed integrally. Furthermore, in this embodiment, the first sealing member 761, the second sealing member 762, and the third sealing member 763 are all formed of sponge, but this is not a limitation. That is, the first sealing member 761, the second sealing member 762, and the third sealing member 763 may be formed of different materials. Moreover, the elasticity of the first sealing member 761 and the second sealing member 762 may differ from the elasticity of the third sealing member 763.

[0106] At the location where a seal 76 is disposed between the first fan duct 27 and the first exhaust filter 73, the gap G is filled by the seal 76. The seal 76 contacts the right end portion 27F of the first fan duct 27 and the second surface 73b of the first exhaust filter 73. In this embodiment, the seal 76 does not contact the housing 713 of the first exhaust fan 71. However, the seal 76 may also contact the housing 713 of the first exhaust fan 71.

[0107] The seal 76 covers the outer periphery of the first exhaust fan 71 while sandwiched between the first exhaust filter 73 and the first fan duct 27. The seal 76 may also cover the outer periphery of the blades 712 of the first exhaust fan 71 while sandwiched between the housing 713 of the first exhaust fan 71 and the first exhaust filter 73.

[0108] like Figure 6 As shown, viewed from the left and right direction, the center C1 of the first exhaust fan 71 and the top of the first exhaust fan 71 are sealed by a first seal 761. Furthermore, viewed from the left and right direction, the center C1 of the first exhaust fan 71 and the processing unit PU are sealed by a second seal 762.

[0109] No seal 76 is provided between the rear wall 27C of the first fan duct 27 and the first exhaust filter 73. Furthermore, no seal 76 is provided between the bottom wall 27E of the first fan duct 27 and the first exhaust filter 73. Also, no seal 76 is provided between the portion of the lower wall 27D of the first fan duct 27 further rearward than the bottom wall 27E and the first exhaust filter 73.

[0110] An opening OP is formed in the portion where the seal 76 is not configured. That is, viewed from the left and right direction, the opening OP is located on the opposite side of the processing unit PU, across the center C1 of the first exhaust fan 71.

[0111] By providing a seal 76 that is sandwiched between the first fan duct 27 and the first exhaust filter 73, the space between the first fan duct 27 and the first exhaust filter 73 can be sealed. In this case, since the seal 76 is formed of an elastomer, the load applied to the first exhaust filter 73 can be reduced by the seal 76, and the airtightness of the first fan duct 27 can be improved.

[0112] In particular, since the seal 76 is formed of sponge as an elastomer, the load applied to the first exhaust filter 73 can be effectively reduced, thereby improving the airtightness between the first exhaust filter 73 and the first fan duct 27.

[0113] Furthermore, by improving the airtightness of the first fan duct 27, when the positive pressure between the first exhaust filter 73 and the first exhaust fan 71 becomes too large due to the exhaust from the first exhaust filter 73, air can be discharged through the opening OP to the opposite side of the processing unit PU. Thus, even if the air discharged by the first exhaust fan 71 contains water vapor, the flow of water vapor-containing air into the processing unit PU can be prevented.

[0114] Furthermore, viewed from the left-right direction, the seal 76 is located between the first exhaust fan 71 and the control board 13 located in front of the first exhaust fan 71. Thus, by positioning the seal 76 between the first exhaust fan 71 and the control board 13, exhaust air from the first exhaust fan 71 can be prevented from flowing towards the control board 13. Therefore, even if the air discharged from the first exhaust fan 71 contains water vapor, the impact of the water vapor on the control board 13 can be suppressed.

[0115] Furthermore, the bottom wall 27E of the first fan duct 27 is located below the first exhaust fan 71, and the opening OP is also formed in the portion of the bottom wall 27E located below the first exhaust fan 71. That is, the seal 76 has an opening OP located below the first exhaust fan 71.

[0116] Therefore, the flow of liquid that has entered the interior of the main body housing 2 and flows along the bottom wall 27E of the pipe is not obstructed by the seal 76, and the liquid can be discharged to the outside of the main body housing 2 through the opening OP below the first exhaust fan 71.

[0117] Alternatively, the seal 76 can be bonded to the first exhaust filter 73, for example. By pre-bonding the seal 76 to the first exhaust filter 73 before supporting it on the right side wall 23, the seal 76 can be positioned between the first exhaust filter 73 and the first fan duct 27 simply by supporting the first exhaust filter 73 on the right side wall 23. This improves the operability of positioning the seal 76 between the first exhaust filter 73 and the first fan duct 27.

[0118] [Grounding spring]

[0119] like Figures 6 to 9 As shown, the image forming apparatus 1 has a grounding spring 75. The grounding spring 75 is supported on the rear wall 27C of the first fan duct 27. The grounding spring 75 is a helical spring formed by winding a conductive and elastic wire.

[0120] The grounding spring 75 includes a first helical portion 751, a second helical portion 752, a first wrist portion 753, and a second wrist portion 754. The first helical portion 751 and the second helical portion 752 are formed into a cylindrical shape by winding wire. The first wrist portion 753 extends from the first helical portion 751 and connects the first helical portion 751 and the second helical portion 752. The second wrist portion 754 is a wrist portion extending from the first helical portion 751, different from the first wrist portion 753. The direction in which the first wrist portion 753 extends from the first helical portion 751 is different from the direction in which the second wrist portion 754 extends from the first helical portion 751.

[0121] The boss 271 protrudes rearward from the rear wall 27C of the first fan duct 27, and the first helical part 751 of the grounding spring 75 is supported on the boss 271 in a rotatable manner.

[0122] The first wrist portion 753 extends diagonally downward to the left from the first spiral portion 751, then bends to the right and extends diagonally downward to the right. The head end of the first wrist portion 753 connects to the second spiral portion 752.

[0123] The second wrist 754 extends rearward from the first spiral portion 751, then bends upward and grounds. The second wrist 754 is grounded, for example, by connecting to a conductive metal frame of the image forming apparatus 1.

[0124] Additionally, a rearwardly protruding protrusion 273 is formed on the rear wall 27C of the first fan duct 27. The second wrist 754 of the grounding spring 75 engages with the protrusion 273 from below.

[0125] The second helical portion 752 of the grounding spring 75 has a rightward force, and the second helical portion 752 contacts the second surface 73b of the first exhaust filter 73 by means of the force of the grounding spring 75. The second helical portion 752 is stably pressed onto the first exhaust filter 73 by the force of the grounding spring 75. The second helical portion 752 applies pressure to the first exhaust filter 73 to the right.

[0126] The second spiral portion 752 contacts the second surface 73b of the first exhaust filter 73, thereby grounding the first exhaust filter 73. The grounding spring 75 is an example of a grounding component that contacts the filter and grounds it. Since the first exhaust filter 73 is grounded by the grounding spring 75, static electricity accumulation in the first exhaust filter 73 can be suppressed, and static electricity discharge from the first exhaust filter 73 to other components such as the first exhaust fan 71 can be suppressed.

[0127] Furthermore, the contact position between the second spiral portion 752 and the first exhaust filter 73 is the portion of the second surface 73b of the first exhaust filter 73 where the opening OP is formed. That is, the grounding spring 75 is disposed on the portion of the seal 76 where the opening OP is formed.

[0128] In this way, by placing the grounding spring 75 in the portion of the seal 76 where the opening OP is formed, the first exhaust filter 73 can be grounded by the grounding spring 75, and pressure can be applied to the first exhaust filter 73 in the portion of the seal 76 where the opening OP is formed.

[0129] In this embodiment, the grounding spring 75 is supported by the rear wall 27C of the first fan duct 27, but it can also be configured to be supported by the opening OP of the lower wall 27D of the duct where the seal 76 is formed.

[0130] In addition, in this embodiment, the grounding spring 75 is a helical spring having a first helical portion 751, a second helical portion 752, a first wrist portion 753, and a second wrist portion 754, but it is not limited to this. As long as the grounding spring 75 has conductivity and elasticity, it can be formed into various shapes.

[0131] [Second exhaust fan, second fan duct, second exhaust filter, and second louver]

[0132] like Figures 2 to 5As shown, the right frame 26 has a second fan duct 28 extending in the left-right direction. The second fan duct 28 is an example of the first duct. The second fan duct 28 is located below the first fan duct 27. The second fan duct 28 extends in the left-right direction, allowing air to circulate in that direction. The second fan duct 28 is formed into a quadrilateral shape when viewed from the left-right direction. A second exhaust fan 72 is fitted into the second fan duct 28. The second fan duct 28 accommodates the second exhaust fan 72.

[0133] The right side wall 23 of the main body housing 2 has a second louver 25 covering the second opening 23b. The second louver 25 is an example of a louver. The second louver 25 connects the interior and exterior of the main body housing 2. In this embodiment, the second louver 25 is formed integrally with the right side wall 23, but it can also be a structure in which the second louver 25 is installed on the right side wall 23 in a detachable manner.

[0134] The second louver 25 is located to the right of the second fan duct 28 and the second exhaust fan 72. That is, the second fan duct 28 and the second exhaust fan 72 are arranged in the left-right direction on the inner side of the main body housing 2, which is closer to the inner side of the main body housing 2 than the second louver 25.

[0135] The second louver 25 has a frame 250 formed into a quadrilateral along the periphery of the exhaust port 23b, and a plurality of blades 251 disposed within the area surrounded by the frame 250. The blades 251 extend in the front-to-back direction and are arranged in a plurality in the up-down direction. The blades 251 tilt upward from left to right, and the air flowing from left to right is redirected to a rightward and upward direction by passing through the second louver 25.

[0136] The second fan duct 28 protrudes further to the right than the second exhaust fan 72. That is, the right end 28F of the second fan duct 28 extends in the left-right direction between the second exhaust fan 72 and the second louver 25. In other words, in the left-right direction, the right end 28F of the second fan duct 28 is closer to the second louver 25 than the second exhaust fan 72.

[0137] The image forming apparatus 1 has a second exhaust filter 74, which is located between two points in the left-right direction: a second louver 25; a second fan duct 28; and a second exhaust fan 72. The second exhaust filter 74 is supported on the right side wall 23. The second exhaust filter 74 is an example of a filter. The second exhaust filter 74 is formed into a quadrilateral shape when viewed from the left-right direction.

[0138] The second exhaust filter 74 has a right-side surface, namely a first surface 74a, and a left-side surface, namely a second surface 74b. The first surface 74a is opposite to the second louver 25 of the right side wall 23, and the second surface 74b is opposite to the second fan duct 28 and the second exhaust fan 72.

[0139] The second exhaust filter 74 is, for example, a honeycomb filter in which the filter material is formed into a honeycomb shape. The honeycomb filter constituting the second exhaust filter 74 has a plurality of pores separated by partitions extending in the left-right direction.

[0140] The filter material constituting the second exhaust filter 74 can be, for example, paper, aluminum, or other metals or ceramics that carry ozone decomposition catalysts such as manganese dioxide or activated carbon. The second exhaust filter 74 is formed in the shape of a rectangular sheet.

[0141] The air inside the substrate cover 12 contained in the main body housing 2 is easily heated by the electronic components mounted on the power supply board 11. The air inside the substrate cover 12 flows from left to right through the second exhaust fan 72, and after dust and other particles are removed by the second exhaust filter 74, it is discharged to the outside of the main body housing 2 through the second louver 25.

[0142] By using the second exhaust fan 72 to expel the air inside the substrate cover 12 to the outside of the main body housing 2, the temperature of the air inside the substrate cover 12 can be reduced. In addition, the amount of dust and other particles contained in the air inside the main body housing 2 can be reduced.

[0143] The second exhaust filter 74 can be any filter capable of removing dust such as toner from the air. In addition, as the second exhaust filter 74, besides capturing and removing dust such as toner, an ozone filter capable of decomposing ozone in the air can also be used.

[0144] The second exhaust fan 72 includes a rotating shaft 721 extending in the left-right direction, blades 722 fixed on the rotating shaft 721, and a housing 723 that supports the rotating shaft 721 in a rotatable manner. It is an axial flow fan that delivers air along the axial direction of the rotating shaft 721. The housing 723 of the second exhaust fan 72 is quadrilateral in shape.

[0145] The housing 723 is shaped to form the shape of the second exhaust fan 72. The housing 723 protrudes further to the right than the blades 722. That is, the right end of the housing 723 extends in the left-right direction between the blades 722 and the second louver 25. In other words, in the left-right direction, the right end of the housing 723 is closer to the second louver 25 than the blades 722.

[0146] like Figure 6As shown, the second fan duct 28 includes an upper duct wall 28A above the second exhaust fan 72, a front duct wall 28B in front of the second exhaust fan 72, a rear duct wall 28C behind the second exhaust fan 72, and a lower duct wall 28D below the second exhaust fan 72. The second fan duct 28 supports the second exhaust fan 72. The second fan duct 28 covers the outer periphery of the second exhaust fan 72.

[0147] A buffer member 78 is disposed between the outer peripheral surface of the housing 723 of the second exhaust fan 72 and the inner peripheral surface of the second fan duct 28. The buffer member 78 closes the gap between the housing 723 of the second exhaust fan 72 and the second fan duct 28.

[0148] A gap G is formed between the second fan duct 28 and the second exhaust filter 74 in the left-right direction. Specifically, a gap G is formed between the right end 28F of the second fan duct 28 and the second exhaust filter 74 in the left-right direction. A seal 76 is disposed in the gap G between the second fan duct 28 and the second exhaust filter 74 in the left-right direction. Specifically, a seal 76 is disposed in the gap G between the right end 28F of the second fan duct 28 and the second exhaust filter 74 in the left-right direction.

[0149] The seal 76 disposed between the second fan duct 28 and the second exhaust filter 74 is formed in the same manner as the seal 76 disposed between the first fan duct 27 and the first exhaust filter 73.

[0150] That is, such as Figure 6 As shown, the seal 76 covers the outer periphery of the second exhaust fan 72 while sandwiched between the second fan duct 28 and the second exhaust filter 74. The seal 76 may also cover the outer periphery of the blades 722 of the second exhaust fan 72 while sandwiched between the housing 723 of the second exhaust fan 72 and the second exhaust filter 74.

[0151] Viewed from the left and right, the center C2 of the second exhaust fan 72 and the top of the second exhaust fan 72 are sealed by the first seal 761. Additionally, viewed from the left and right, the center C2 of the second exhaust fan 72 and the processing unit PU are sealed by the second seal 762.

[0152] No seal 76 is provided between the rear wall 28C of the second fan duct 28 and the second exhaust filter 74, and between the rear part of the lower wall 27D of the second fan duct 28 and the second exhaust filter 74; instead, an opening OP is formed. Viewed from the left and right, the opening OP is located on the opposite side of the processing unit PU, separated from the center C2 of the second exhaust fan 72.

[0153] By setting the seal 76 in a state where it is sandwiched between the second fan duct 28 and the second exhaust filter 74, the load applied to the second exhaust filter 74 can be reduced, and the airtightness of the second fan duct 28 can be improved.

[0154] Furthermore, when the positive pressure between the second exhaust filter 74 and the second exhaust fan 72 becomes too high due to the exhaust from the second exhaust filter 74, air can be discharged through the opening OP to the opposite side of the processing unit PU. Thus, even if the air discharged by the second exhaust fan 72 contains water vapor, the flow of water vapor-containing air into the processing unit PU can be prevented.

[0155] Furthermore, viewed from the left and right direction, the seal 76 is located between the second exhaust fan 72 and the control board 13 located in front of the second exhaust fan 72. Thus, by providing the seal 76 between the second exhaust fan 72 and the control board 13, it is possible to suppress exhaust flow from the second exhaust fan 72 towards the control board 13. Therefore, even if the air discharged from the second exhaust fan 72 contains water vapor, it is possible to suppress the water vapor from affecting the control board 13.

[0156] A grounding spring 75 is supported on the rear wall 28C of the second fan duct 28. The grounding spring 75 is disposed in the portion of the seal 76 that has an opening OP.

[0157] The second helical portion 752 of the grounding spring 75 contacts the second surface 74b of the second exhaust filter 74, and the second exhaust filter 74 is pressed to the right by the second helical portion 752. Furthermore, the second exhaust filter 74 is grounded through the contact between the second helical portion 752 and the second exhaust filter 74.

[0158] [Intake fan and intake duct]

[0159] like Figure 4 and Figure 10 As shown, the intake fan 77 is supported on the right side of the right frame 26. The intake fan 77 is, for example, a centrifugal fan that draws in air along the rotation axis and discharges it in a centrifugal direction orthogonal to the rotation axis. The intake fan 77 is positioned inside the main body housing 2 with the rotation axis in the left-right direction, and draws air from outside the main body housing 2 into the interior of the main body housing 2 through the intake port 23c.

[0160] The intake fan 77 has an intake section 77a for drawing in air and an exhaust section 77b for discharging air. The intake section 77a is opposite to the intake port 23c on the right side wall 23. The exhaust section 77b is located at the upper end of the intake fan 77 and exhausts air upwards.

[0161] An air intake duct 264 is formed on the right side of the right frame 26. The air intake duct 264 is an example of a second duct. The air intake duct 264 is an intake passage for guiding the air drawn in by the intake fan 77 to the processing unit PU. The air intake duct 264 extends upward from the exhaust section 77b of the intake fan 77 and then extends rearward.

[0162] In the portion of the right frame 26 where the air intake duct 264 is formed, an air intake hole 264a is formed that extends through in the left-right direction. The air intake holes 264a are formed at four positions corresponding to the processing box 50 and the photosensitive drum 51 arranged in the front-back direction.

[0163] Air drawn in from the outside of the main housing 2 by the intake fan 77 is guided along the right side of the right frame 26 by the intake pipe 264 and flows out to the left through the intake port 264a. The air flowing out to the left from the intake port 264a reaches the processing unit PU, which is located inside the main housing 2, further than the right frame 26. In this way, the intake pipe 264 guides the air generated by the intake fan 77 to the processing unit PU in a left-right direction.

[0164] When the air that has passed through the processing unit PU is discharged by the first exhaust fan 71, the space inside the main housing 2 that contains the processing unit PU tends to become under negative pressure. In this case, if the negative pressure in the space containing the processing unit PU is too large, the exhaust generated by the first exhaust fan 71 may leak from between the first exhaust filter 73 and the first fan duct 27 and flow toward the processing unit PU side.

[0165] Therefore, by guiding the air intake of the intake fan 77 to the processing unit PU through the intake pipe 264, excessive negative pressure in the accommodating space of the processing unit PU can be suppressed. This, in turn, prevents the exhaust from the first exhaust fan 71 from flowing towards the processing unit PU.

[0166] Furthermore, if the intake fan 77 is mounted on the right frame 26, and no seal 76 is provided between the first exhaust filter 73 and the first fan duct 27, exhaust from the first exhaust fan 71 may be drawn into the intake fan 77 through the space between the right frame 26 and the right side wall 23.

[0167] If the air exhausted by the first exhaust fan 71 is heated by the fuser 60, and is guided to the processing unit PU by the intake fan 77, the housing space of the processing unit PU in the main body housing 2 will heat up. In addition, if the air exhausted by the first exhaust fan 71 contains water vapor, the water vapor may affect the control board 13, which serves as the high-voltage board.

[0168] However, in the image forming apparatus 1, the seal 76, which is sandwiched between the first fan duct 27 and the first exhaust filter 73, is located between the first exhaust fan 71 and the control board 13 located in front of the first exhaust fan 71.

[0169] Therefore, it is possible to suppress the exhaust flow of the first exhaust fan 71 towards the control board 13. Furthermore, it is possible to suppress the exhaust from the first exhaust fan 71 from reaching the intake fan 77 located below and in front of the control board 13. As a result, it is possible to suppress the temperature rise of the housing space of the processing unit PU in the main body housing 2, and to suppress the influence of air containing water vapor on the control board 13.

[0170] To prevent exhaust from the first exhaust fan 71 from being drawn into the intake fan 77, a sealing member can be disposed between the intake fan 77 and the right side wall 23, surrounding the outer periphery of the intake portion 77a of the intake fan 77 and the intake port 23c of the right side wall 23. In this case, as the sealing member surrounding the outer periphery of the intake portion 77a of the intake fan 77 and the intake port 23c of the right side wall 23, an elastic member such as a sponge can be used, similar to the case of the seal 76.

[0171] Explanation of reference numerals in the attached figures

[0172] 1: Image forming apparatus

[0173] 2: Body shell

[0174] 13: Control board

[0175] 23: Right side wall

[0176] 24: The First Venetian Blind

[0177] 25: The Second Venetian Blind

[0178] 27: First fan duct

[0179] 28: Second fan duct

[0180] 50: Processing box

[0181] 51: Photosensitive drum

[0182] 52: Developing roller

[0183] 54: With electrical appliances

[0184] 60: Fixer

[0185] 71: First exhaust fan

[0186] 72: Second exhaust fan

[0187] 73: First exhaust filter

[0188] 74: Second exhaust filter

[0189] 75: Grounding spring

[0190] 76: Seals

[0191] 77: Intake fan

[0192] 264: Intake pipe

[0193] C1: (First exhaust fan) center

[0194] C2: (Second exhaust fan) center

[0195] OP: Opening

[0196] PU: Processing Unit

[0197] S: Sheet

Claims

1. An image forming apparatus, comprising: The main body housing has louvers; The processing unit includes a photosensitive drum that rotates about an axis and a developer that supplies toner to the photosensitive drum for forming a toner image on a sheet. A fuser is used to heat and fix a sheet containing toner to form an image; An exhaust fan, used to exhaust air from the main housing, is positioned in a location that does not overlap with the processing unit when viewed from the axial direction of the photosensitive drum, and is closer to the inner side of the main housing than the louvers in the axial direction. A first duct has an end that is closer to the louver than the exhaust fan in the axial direction, and the exhaust fan is housed in the interior space of the first duct; A filter is disposed in the axial direction between the louver and the end of the first pipe; as well as A seal, made of an elastomer, surrounds the outer periphery of the exhaust fan in a state where it is sandwiched between the end of the first pipe and the filter in the axial direction, and closes the treatment section between the center of the exhaust fan when viewed from the axial direction, and has an opening on the opposite side of the treatment section located across the center of the exhaust fan when viewed from the axial direction.

2. The image forming apparatus according to claim 1, characterized in that, Viewed from the axial direction, the exhaust fan is located above the fuser.

3. The image forming apparatus according to claim 1, characterized in that, Viewed along the axial direction, the exhaust fan is positioned below the fuser. The image forming apparatus has a first substrate disposed at a position overlapping with the exhaust fan when viewed from the axial direction.

4. The image forming apparatus according to any one of claims 1 to 3, characterized in that, The seal has an opening located below the exhaust fan.

5. The image forming apparatus according to any one of claims 1 to 3, characterized in that, It also includes a grounding component that contacts the filter to ground it. The grounding component is disposed on the portion of the first conduit that overlaps with the opening of the seal in the axial direction.

6. The image forming apparatus according to any one of claims 1 to 3, characterized in that, The processing unit includes a developing roller. The body housing has a first side surface located at one end in the axial direction. The exhaust fan is located within the main housing, closer to the first side than the center of the main housing in the axial direction. The image forming apparatus has a second substrate for applying a developing bias to the developing roller. The second substrate is located in the body housing and is closer to the first side in the axial direction than the center of the body housing. It is positioned to overlap with the processing unit but not with the exhaust fan when viewed from the axial direction.

7. The image forming apparatus according to any one of claims 1 to 3, characterized in that, The seal is made of sponge.

8. The image forming apparatus according to any one of claims 1 to 3, characterized in that, Also includes: An intake fan is used to draw air into the main body housing; as well as The second pipe is used to guide the air intake of the intake fan along the axial direction to the processing unit.

9. The image forming apparatus according to any one of claims 1 to 3, characterized in that, The processing unit has an electrical charge device for charging the photosensitive drum. The filter is an ozone filter capable of breaking down ozone in the air that passes through it.

Images