Image forming apparatus

Abstract

To provide an image forming apparatus capable of preventing dust and other particles from entering the inside of the image forming apparatus. [Solution] The image forming apparatus comprises an image forming unit that forms an image on a recording material, a fixing unit that heats the recording material on which the image has been formed in the image forming unit, an outer casing that houses the image forming unit and the fixing unit, a paper discharge unit on which the heated recording material is discharged, a stacking unit on which the discharged recording material is placed, an upper surface that is positioned above the image forming unit in the vertical direction and faces upward, and includes a recess 79a that is recessed downward, with at least a part of the stacking unit placed in the recess 79a, and a communication passage 80 that communicates with the space S1 in which the image forming unit is housed and the recess 79a, and a blower unit that has an exhaust port opening to the outside of the outer casing and an exhaust fan that generates an airflow from the space S1 to the exhaust port, and a filter 90 is provided in the communication passage 80.

Description

Technical Field

[0006] , , ,

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

Background Art

[0002] As an image forming apparatus for forming and fixing a toner image on a recording material, a configuration is known in which an intake section that takes in air from the outside to the inside of the image forming apparatus and an exhaust section that exhausts the warmed air inside to the outside are provided.

[0003] Patent Document 1 discloses a configuration including an exhaust unit that discharges the air inside the image forming apparatus to the outside through a discharge section where the recording material is discharged, and cools the inside of the apparatus main body. According to such an image forming apparatus, since the exhaust unit blows air toward the recording material discharged from the discharge port, the heated recording material is cooled, and it is possible to suppress the recording materials from sticking to each other.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In recent years, with the increase in the printing speed of image forming apparatuses, it has been required to more efficiently cool the inside of the apparatus main body. In order to efficiently cool the inside of the apparatus main body, it is preferable to efficiently take in air from the outside of the image forming apparatus. However, when taking in air from the outside of the image forming apparatus, there is a possibility that dust and the like may enter the inside of the image forming apparatus.

[0006] Therefore, an object of the present invention is to provide an image forming apparatus capable of suppressing the entry of dust and the like into the inside of the image forming apparatus.

Means for Solving the Problems

[0007] The image forming apparatus of the present invention, for achieving the above objectives, An image forming unit that forms an image on the recording material, A fixing unit that heats the recording material on which an image has been formed in the image forming unit, An outer casing that houses the image forming unit and the fixing unit, A paper discharge section from which the recording material heated in the fixing section is discharged, A stacking section on which the recording material discharged from the aforementioned paper discharge section is placed, An upper surface portion located above the image forming portion in the vertical direction and facing upward, including a recess that curves downward, in which at least a part of the loading portion is placed; A communication passage that connects the space in which the image forming unit is housed to the recess, An exterior part having, A blower unit having an exhaust port opening to the outside of the exterior part and an exhaust fan that generates an airflow from the space toward the exhaust port, Equipped with, The aforementioned communication passage is characterized by being provided with a filter. [Effects of the Invention]

[0008] According to the present invention, an image forming apparatus can be made capable of suppressing the intrusion of dust and other particles into the inside of the image forming apparatus. We can provide a place for you. [Brief explanation of the drawing]

[0009] [Figure 1] This is an overall perspective view of the image forming apparatus according to Example 1. [Figure 2] This is a schematic cross-sectional view of the image forming apparatus according to Example 1. [Figure 3] This is a perspective view showing the internal configuration of the image forming apparatus according to Example 1. [Figure 4] This diagram shows the configuration of the intake unit according to Example 1. [Figure 5] This diagram shows the configuration of the blower unit according to Example 1. [Figure 6] It is a cross-sectional view of an image forming apparatus around a blower unit according to Example 1. [Figure 7] It is a diagram showing the air flow of the image forming apparatus according to Example 1. [Figure 8] It is a diagram showing the configuration of the upper cover unit and the communication path according to Example 1. [Figure 9] It is a schematic diagram showing a state in which a toner supply container according to Example 1 is mounted. [Figure 10] It is a diagram showing the configuration of the upper cover unit and the communication path according to Example 2.

Mode for Carrying Out the Invention

[0010] Hereinafter, with reference to the drawings, modes for carrying out this invention will be exemplarily and specifically described based on the embodiments. However, dimensions, materials, shapes, relative arrangements, etc. of the components described in this embodiment should be appropriately changed according to the configuration of the apparatus to which the invention is applied and various conditions. That is, it is not intended to limit the scope of this invention to the following embodiments. Also, not all of the features described in the following embodiments are essential for the solution means of the invention.

[0011] (Example 1) An example in which the present invention is applied to an electrophotographic laser beam printer will be described as Example 1. The image forming apparatus 1 according to Example 1 is a monochrome laser beam printer using an electrophotographic process, and forms an image with a developer (toner) on a recording material P according to image information transmitted from an external device such as a personal computer. Examples of the recording material P include recording paper, label paper, OHP sheets, cloth, and the like.

[0012] [Overall Configuration of Image Forming Apparatus] The overall configuration of the image forming apparatus 1 according to Embodiment 1 will be described. In the following description, when the image forming apparatus 1 is installed on a horizontal plane, the vertical direction is defined as the Z direction. In other words, the Z direction is the vertical direction when the image forming apparatus 1 is in use. A direction that intersects the Z direction and is parallel to the axial direction (main scanning direction) of the photosensitive drum 11 described later is defined as the X direction. A direction that intersects the X direction and the Z direction is defined as the Y direction. The X direction, Y direction, and Z direction preferably intersect perpendicularly to each other. For the sake of convenience, the plus side in the X direction is referred to as the right side, the minus side as the left side, the plus side in the Y direction as the front side, the minus side as the rear side, the plus side in the Z direction as the upper side, and the minus side as the lower side. The right side can be referred to as one end side in the X direction, and the left side as the other end side in the X direction. The front side can be referred to as one end side in the Y direction, and the back side as the other end side in the Y direction.

[0013] FIG. 1 is a perspective view showing the overall appearance of the image forming apparatus 1 according to Embodiment 1. FIG. 2 is a schematic cross-sectional view of the image forming apparatus 1 cut along a plane perpendicular to the X direction. FIG. 3 is a perspective view showing the internal configuration of the image forming apparatus 1. As shown in FIG. 1, the image forming apparatus 1 is provided with a feed tray 4 capable of loading and accommodating a plurality of recording materials P, and a discharge tray unit 30 on which the recording materials P discharged from the discharge port 15 are loaded. In the image forming apparatus 1, the paper feed direction D1 for feeding the recording material P from the feed tray 4 is a direction from the front side to the rear side, and the paper discharge direction D2 for discharging the recording material P from the discharge port 15 is a direction from the rear side to the front side.

[0014] The image forming apparatus 1 is surrounded by an exterior portion 70 having a plurality of covers. The exterior portion 70 has a front cover 71 that covers the front side of the image forming apparatus 1, an upper cover unit 79, side covers 72 that cover the left and right side surfaces, and a rear cover 77 (shown in FIG. 2) that covers the rear side. The upper cover unit 79 has a first upper cover (first frame body, first cover) 75 and a second upper cover (second frame body 、second cover) 76. The exterior portion 70 discharges the recording material P from the inside of the image forming apparatus 1 It has a paper discharge section and a stacking section (storage section) on which the recording material discharged from the paper discharge section is placed.

[0015] The first upper cover 75 and the second upper cover 76 are attached to the right plate 73 and the left plate 74, which are frame members of the main body of the image forming apparatus 1. The first upper cover 75 and the second upper cover 76 may also be configured to be able to engage with each other by a snap-fit ​​configuration or the like. The upper cover unit 79 further includes an output tray 14 that is rotatably supported by the second upper cover 76. The output tray unit 30 includes the output tray 14 and the second upper cover 76, which is a support cover, and is located at the top of the image forming apparatus 1. In other words, the output tray unit 30 is also a component of the upper cover unit 79.

[0016] The upper cover unit 79 has an upper surface facing upward (positive side in the Z direction) and includes a recessed area 79a that is recessed downward. In Embodiment 1, the sides of the recessed area 79a are formed by the first upper cover 75. At least a portion of the discharge tray 14 is located in the recessed area 79a. In other words, at least a portion of the loading area is located in the recessed area 79a. More specifically, the loading area is provided at the bottom of the recessed area 79a. In other words, the bottom of the recessed area 79a forms at least a portion of the loading area on which the recording material P is placed. In this embodiment, a portion of the discharge tray 14 protrudes from the recessed area 79a, but the entire discharge tray 14 may be located inside the recessed area 79a.

[0017] The upper cover unit 79 has an outlet 15 as a paper discharge section through which the recording material P is discharged. In Embodiment 1, the outlet 15 is formed in the first upper cover 75. However, the configuration is not limited to this, and for example, the outlet 15 may be formed by the first upper cover 75 and the second upper cover 76. The upper cover unit 79 is also provided with a plurality of operation buttons 81 for the user to operate the image forming apparatus 1.

[0018] The image forming apparatus 1 comprises a right-side plate 73 (first side plate) positioned on the right side, a left-side plate 74 (second side plate) positioned on the left side, and a central frame 83 bridging the gap between the right-side plate 73 and the left-side plate 74, as frame members (plate members) of the apparatus body. The right-side plate 73 and the left-side plate 74 are plate-shaped frames having surfaces perpendicular to the X direction, and are arranged side by side in the width direction (X direction in Embodiment 1) intersecting the transport direction and paper discharge direction D2 of the recording material P. The image forming section and fixing section of the image forming apparatus 1 are arranged in the space between the right-side plate 73 and the left-side plate 74. The right-side plate 73 and the left-side plate 74 are each formed from sheet metal.

[0019] Referring to Figure 2, the process of printing (forming) a toner image on the recording material P will be explained in the order of the image formation process and the transport process. First, the image formation process will be explained. The image forming apparatus 1 has a scanner unit 50 and a developing process unit 20 which serves as the image forming section. The developing process unit 20 is equipped with a photosensitive drum 11, a developing roller 12, a static eliminator 13, a charging roller 17, and a toner container 18. The upper cover unit 79 is located above the scanner unit 50 and the developing process unit 20 and covers them from above.

[0020] When image information is transmitted from an external device to the image forming apparatus 1, the photosensitive drum 11 is driven to rotate at a predetermined peripheral speed (process speed) in the direction of arrow R based on the print start signal. The scanner unit 50 irradiates the photosensitive drum 11 with laser light based on the input image information. The scanner unit 50 has a laser oscillator that outputs laser light, This unit includes a polygon mirror and lens for irradiating the photosensitive drum 11 with scanner light, a scanner motor for rotating the polygon mirror, and a frame that integrally supports these components.

[0021] The surface of the photosensitive drum 11 is first charged with a predetermined charge by the charging roller 17 after the remaining toner has been removed by the static elimination device 13, and when laser light is shone on it, an electrostatic latent image is formed on the surface of the photosensitive drum 11. Then, the toner in the toner container 18 is transported to the photosensitive drum 11 by the developing roller 12, and the electrostatic latent image is developed by the toner, forming a toner image on the surface of the photosensitive drum 11.

[0022] Next, the transport process will be described. In order to transport the recording material P contained in the transport tray 4 toward the photosensitive drum 11, the pickup roller 3, the transport roller 5a, the separation pad 5b, and the transport roller pair 5c are arranged in this order on the transport path 31 of the recording material P. The transport of the recording material P contained in the transport tray 4 begins in parallel with the start of the image forming process.

[0023] In the feeding operation of the recording material P, first the drive motor 60 located inside the image forming apparatus 1 is activated, causing each roller to rotate. Then, the pickup roller 3 rotates and contacts the top surface of the stack of recording material P contained in the feeding tray 4, feeding the recording material P toward the feeding roller 5a and the separation pad 5b.

[0024] The separation pad 5b is positioned to press against the feed roller 5a, and the feed roller 5a and the separation pad 5b form a separation nip. Here, the uppermost recording material P may be fed together with other recording materials P in contact with the lower surface, causing multiple sheets to be fed to the separation nip. In that case, the frictional force of the separation pad 5b at the separation nip separates the lower recording material P, allowing only the uppermost recording material P to be transported downstream.

[0025] The transported recording material P is carried toward the photosensitive drum 11 by a pair of transport rollers 5c. The photosensitive drum 11, on which a toner image has been formed by the image forming process, forms a transfer nip with a transfer roller 7 positioned on the transport path 31 so as to be pressed against the photosensitive drum 11. When the recording material P is transported toward the transfer nip, a transfer bias is applied to the transfer roller 7, and the toner image formed on the photosensitive drum 11 is transferred to the recording material P.

[0026] The recording material P onto which the toner image has been transferred is heated and pressurized by the fixing device 9, thereby fixing the toner image to the recording material P. The fixing device 9 is a fixing unit (heating unit) having a heating roller 9a with a built-in heater (not shown) and a pressure roller 9b that is biased toward the heating roller 9a.

[0027] The recording material P on which the toner image has been fixed is then discharged to the discharge tray 14 via the discharge port 15 by the discharge roller pair 10. On the other hand, when an image is to be formed on both sides of the recording material P, the discharge roller pair 10 switches back the recording material P on which the image has been formed on the first printing surface and guides it to the double-sided transport path 16.

[0028] The recording material P, guided along the double-sided transport path 16, is U-turned from the lower side to the upper side by the double-sided transport roller pair 5d and transported again toward the transfer roller 7. At this time, the recording material P is transported toward the photosensitive drum 11 with the second printing surface, opposite to the first printing surface, and a toner image is transferred in the same process as the image formation process for the first printing surface. After an image is formed on the second printing surface by the transfer roller 7, the recording material P is discharged into the discharge tray 14 by the discharge roller pair 10.

[0029] As explained above, the toner image is printed onto the recording material P through the image formation process and the transport process. Also, as shown in Figure 3, the toner container 18 of the developing process unit 20 A supply port 200 for replenishing toner, which is used as a developer, is connected to it. The toner container 18 is configured to allow toner to be replenished from the outside when the amount of toner in it falls below a predetermined amount.

[0030] As shown in Figures 2 and 3, the image forming apparatus 1 includes a circuit board 100. The circuit board 100 includes a wiring board 101 made of an insulator and electronic components 111 soldered to the wiring board 101. Conductor wiring is provided on and inside the wiring board 101, and electricity is supplied to the electronic components 111 through this wiring.

[0031] The circuit board 100 converts the alternating current supplied from outside the image forming apparatus 1 into a direct current and converts the input voltage to obtain a predetermined voltage value necessary for the image forming process. At this time, electronic components 111 such as field-effect transistors (FETs) consume power and generate heat in order to control the current. To reduce the temperature rise inside the image forming apparatus 1 due to the heat generated by the electronic components 111, the image forming apparatus 1 is provided with an intake fan 301. The intake fan 301 draws in outside air and blows the air towards the heat-generating electronic components 111 to cool them. The intake fan 301 is located on the outside of the left side panel 74, adjacent to the front of the left side panel 74.

[0032] Furthermore, the recording material P, on which the image has been fixed, is heated by the heating roller 9a, and if it is loaded onto the discharge tray 14 while still hot, the recording material P may stick to each other. Therefore, to prevent the recording material P from sticking together, the image forming apparatus 1 is provided with an exhaust fan 405. The exhaust fan 405 blows air towards the recording material P near the discharge roller pair 10 to cool the recording material P.

[0033] [Intake unit configuration] The configuration of the intake unit 300 of the image forming apparatus 1, including the intake fan 301, will be explained in detail using Figures 4(a) and 4(b). Figures 4(a) and 4(b) show the configuration of the intake unit 300 according to Embodiment 1. The intake unit 300 is an intake section for supplying air from the outside to the inside of the image forming apparatus 1. The intake unit 300 includes an intake fan 301, a side opening 303 that connects the inside and outside of the image forming apparatus 1, and a duct member 302 that guides the airflow drawn in and blown out by the intake fan 301.

[0034] Figure 4(a) is a perspective view showing a side opening 303 provided in the side cover 72 of the exterior member of the image forming apparatus 1. Figure 4(a) shows the arrangement relationship between the side opening 303 and the intake fan 301. The side cover 72 is provided with a side opening 303 for drawing in outside air from the image forming apparatus 1 and bringing it into the interior. The side opening 303 is an opening for an intake unit 300 that connects the outside and inside of the image forming apparatus 1, and the side opening 303 may also be considered as part of the components of the intake unit 300. As shown in Figure 3, the intake unit 300 is positioned in front of the left side plate 74.

[0035] The intake fan 301 in Embodiment 1 is an axial flow fan, which is a device for drawing in air, and is positioned adjacent to the side opening 303. The intake fan 301 is powered by the circuit board 100. When the intake fan 301 is driven, air flows in the intake direction Fa, which is from left to right, and air is drawn into the image forming apparatus 1 through the side opening 303.

[0036] Figure 4(b) is a rear-view cross-sectional view showing the airflow generated by the operation of the intake fan 301. The intake fan 301 is held in place by a duct member 302 that guides the airflow. The duct member 302 is configured to guide the airflow from the intake fan 301 in two directions toward the electronic components 111 and the scanner unit 50 provided on the circuit board 100. In Embodiment 1, the intake unit 300 The exhaust direction Fb is divided into two directions, both of which are from the left side to the right side of the image forming apparatus 1.

[0037] The scanner unit 50 is positioned above the electronic component 111. The electronic component 111 is an electrical element that generates heat during image formation. Due to the heat generated by the electronic component 111, the scanner unit 50's temperature rises. Inside the scanner unit 50 are a polygon mirror, a lens, and a scanner motor (not shown). If the temperature rises too high, the polygon mirror and lens will expand, leading to misalignment of the laser beam's irradiation position and deterioration of the scanner motor. To prevent such malfunctions, air supplied by the intake fan 301 is guided by the duct member 302, cooling both the scanner unit 50 and the electronic component 111.

[0038] [Air blower unit configuration] The configuration of the blower unit 40 (exhaust unit), including the exhaust fan 405, will be explained using Figures 5(a), (b), 6, and 7. Figure 5(a) is a perspective view of the blower unit 40. The blower unit 40 is a blower unit (exhaust unit) that blows (exhausts) the air inside the image forming apparatus 1 to the outside. The blower unit 40 includes an exhaust fan 405 that generates an airflow from the inside to the outside of the image forming apparatus 1, an exhaust fan cover 402 that has an intake port 403 and covers the exhaust fan 405, and an exhaust fan holder 401 that has an exhaust port 404.

[0039] The exhaust fan cover 402 has multiple intake ports 403 arranged side by side at predetermined intervals in the width direction (X direction). The exhaust fan holder 401 is also provided with multiple exhaust ports 404 that open upward in the Z direction and are located between the multiple intake ports 403.

[0040] Figure 5(b) is a perspective view of the exhaust fan 405. The exhaust fan 405 has a rotating shaft 406 that can rotate about a rotation axis extending in the X direction, blades 407 provided on the rotating shaft 406, and a drive unit 408 provided at one end of the rotating shaft 406 in the axial direction. The exhaust fan 405 is a blower fan that is rotatably held by an exhaust fan holder 401 and discharges air drawn in from the intake port 403 from the exhaust port 404.

[0041] The blades 407 are positioned in the same location as the exhaust port 404 in the X direction. The drive unit 408 receives power from the drive motor 60, causing the rotation axis 406 of the exhaust fan 405 to rotate integrally with the blades 407, and the air flowing in from the intake port 403 is exhausted upward in the Z direction from the exhaust port 404.

[0042] Figure 6 is a cross-sectional view of the image forming apparatus 1 around the blower unit 40, and is a cross-sectional view taken when viewing the image forming apparatus 1 towards the positive side in the X direction. The blower unit 40 is located below the discharge roller pair 10 and the discharge port 15, adjacent to the fixing device 9 in the Y direction. The blower unit 40 is attached to the central frame 83 which bridges the right side plate 73 (first side plate) and the left side plate 74 (second side plate).

[0043] The central frame 83 has a flow path 410 for guiding the air discharged from the exhaust port 404 and discharging it to the outside of the image forming apparatus 1. The flow path 410 has a communication port 411 formed to match the position of the exhaust port 404, and an exhaust port 412 that opens to the outside of the image forming apparatus 1 via the discharge port 15. The communication port 411 opens downward in the Z direction and is an opening that communicates with the exhaust port 404. The exhaust port 412 opens forward in the Y direction and is an opening that opens to the outside of the image forming apparatus 1. The exhaust port 412 is located below the discharge roller pair 10. The exhaust fan 405 generates an airflow from the exhaust port 412 toward the recess 79a. In this embodiment... Then, air flows from the exhaust port 412 through the outlet port 15 into the recess 79a. In Embodiment 1, the central frame 83 that forms the flow path 410 is also a component of the blower unit 40, and together with the exhaust fan holder 401 and the exhaust fan cover 402, it forms the flow path of the blower unit 40. In other words, the blower unit 40 has a flow path through which air flows from the intake port 403 to the exhaust port 412. With this configuration, the blower unit 40 discharges the air inside the image forming apparatus 1 to the outside of the image forming apparatus 1 through the exhaust port 412. The exhaust fan cover 402 and the exhaust fan holder 401 form a housing frame that houses the exhaust fan 405. In other words, the housing frame has an intake port 403 and an exhaust port 404. The central frame 83 can also be said to be part of the housing frame.

[0044] The intake port 403 of the blower unit 40 opens into the space S1 (internal space) between the right plate 73 and the left plate 74, and the blower unit 40 is positioned to draw in air from space S1. The intake port 403 opens on the front side of the image forming apparatus 1 (downstream in the paper discharge direction D2 from which the recording material P is discharged from the discharge port 15). In other words, since the intake port 403 faces away from the fuser 9, the blower unit 40 is prevented from drawing in air heated by the fuser 9. The rotation of the exhaust fan 405 causes the air inside the apparatus to flow in the intake direction Fc and is drawn into the intake port 403. The drawn-in air is exhausted to the outside of the outer casing 70 from the exhaust port 412. More specifically, the intake air is guided in the blowing direction Fd from the exhaust port 404 toward the exhaust roller pair 10, and is blown out from the underside of the exhaust roller pair 10 toward the recording material P discharged from the exhaust roller pair 10 toward the exhaust direction Fe. In other words, the exhaust fan 405 creates an airflow from space S1 toward the exhaust port 412. In Embodiment 1, as shown in Figure 6, the intake direction Fc is toward the rear in the Y direction, the blowing direction Fd is toward the upper in the Z direction, and the exhaust direction Fe is toward the front in the Y direction.

[0045] Figures 7(a) and 7(b) show the airflow in the image forming apparatus 1. Figures 7(a) and 7(b) show the airflow formed inside the image forming apparatus 1 by the intake unit 300 and the blower unit 40. Figure 7(a) is a cross-sectional view of the image forming apparatus 1 when viewed towards the positive side in the X direction. Figure 7(b) is a perspective view showing the internal configuration of the image forming apparatus 1.

[0046] The intake fan 301, located on the outside of the left panel 74, draws in air in an intake direction Fa toward the right in the X direction through the side opening 303 of the side cover 72. The air discharged from the intake fan 301 flows in an exhaust direction Fb, guided by the duct member 302, and blows onto the scanner unit 50, located in the area between the right panel 73 and the left panel 74, and the electronic components 111, located on the back of the wiring board 101. The air in the exhaust direction Fb cools the scanner unit 50 and the electronic components 111. At this time, the ambient temperature around the scanner unit 50 and the electronic components 111 becomes, for example, approximately 50°C.

[0047] The blower unit 40 draws in air from the space S1 between the right plate 73 and the left plate 74, more specifically, the air around the scanner unit 50, in the intake direction Fc. This airflow prevents heat from accumulating around the scanner unit 50, so the blower unit 40 can be cooled more effectively according to the configuration of Embodiment 1 compared to a configuration in which only air is blown in by the intake unit 300.

[0048] Within the blower unit 40, air drawn in in the intake direction Fc flows in the blowing direction Fd, passes through the exhaust port 404 and the communication port 411, and is discharged from the exhaust port 412 in the exhaust direction Fe. As the recording material P is discharged from the discharge port 15 and placed on the discharge tray 14, the air discharged from the exhaust port 412 hits the recording material P, cooling it. The recording material P that has passed through the discharge roller pair 10 is heated by the heating roller 9a, and its temperature is, for example, 60°C.

[0049] In order for the air blower unit 40 to effectively cool the recording material P, it is preferable that the temperature of the air discharged by the air blower unit 40 be low. Therefore, in Embodiment 1, a communication passage 80 is provided near the air intake port 403 of the air blower unit 40, connecting the inside and outside of the image forming apparatus 1. By taking in outside air from the image forming apparatus 1, the temperature of the air inside the image forming apparatus 1 is lowered, as is the temperature of the air flowing through the air blower unit 40, thereby improving the cooling performance of the recording material P. The detailed configuration of the communication passage 80 will be described below.

[0050] [Connection and filter configuration] The configuration of the connecting passage 80 will be explained using Figures 8(a), (b), and (c). Figures 8(a) to (c) show the configuration of the upper cover unit 79 and the connecting passage 80 according to Embodiment 1. In Embodiment 1, the connecting passage 80 is provided in the upper cover unit 79 and is formed by a first upper cover 75 and a second upper cover 76. In this embodiment, as shown by the dotted line L1 in Figure 8(a), the connecting passage 80 has a portion extending in the Y direction and a portion extending in the X direction.

[0051] Figure 8(a) shows the relationship between the first upper cover 75 and the second upper cover 76 that form the connecting passage 80. The second upper cover 76 covers the upper side of the device in the area where the discharged recording material P is loaded, and the first upper cover 75 covers the upper side of the device in the other areas.

[0052] As shown in Figure 1, the loading section of the discharge tray 14 has an upstream end 14a and a downstream end 14b in the paper discharge direction D2. The loading section of the discharge tray 14 slopes upward from the upstream end 14a to the downstream end 14b. As shown in Figures 1 and 6, the connecting passage 80 is closer to the upstream end 14a than to the downstream end 14b. Also, the connecting passage 80 is located below the discharge port 15.

[0053] Figure 9 is a schematic diagram showing how the toner supply container TC is mounted on the developing process unit 20. As shown in Figure 9, the toner supply container TC is detachably mounted on the developing process unit 20. More specifically, the developing process unit 20 is provided with a supply port 200, and the second upper cover 76 is provided with an opening 76d. The toner supply container TC is permitted to be mounted on the developing process unit 20 through the opening 76d and the supply port 200. The discharge tray 14 is configured to swing (see Figure 6). The discharge tray 14 is supported by the second upper cover 76 so as to swing between a first position on which the recording material P is placed and which covers the opening 76d, and a second position on which the opening 76d is exposed. The discharge tray 14 moves from the first position to the second position by swinging in the swing direction E1 shown in Figure 6, about a swing axis parallel to the X direction. With this configuration, by moving the output tray 14 to the second position, the operator can supply toner to the developing process unit 20 without removing the second upper cover 76 or the output tray 14.

[0054] The first upper cover 75 is mounted on the right side plate 73 and the left side plate 74. The first upper cover 75 is provided with first vertical wall portions 75a extending downward in the Z direction at positions corresponding to both ends of the second upper cover 76 in the X direction. The first vertical wall portions 75a are provided at positions opposite to the left and right sides of the second upper cover 76. In addition, second vertical wall portions 76a extending upward in the Z direction are provided at both ends of the second upper cover 76 (left and right in the X direction). The second vertical wall portions 76a include the end faces which are the sides of the second upper cover 76. When the second upper cover 76 is mounted on the first upper cover 75 from above, the left and right second vertical wall portions 76a are mounted so as to be aligned with the first vertical wall portions 75a.

[0055] Figure 8(b) is a cross-sectional view showing the configuration of the connecting passage 80 according to Embodiment 1, and shows the positional relationship between the first upper cover 75 and the second upper cover 76. Figure 8(b) is a cross-sectional view of the upper cover unit 79 when viewed in the Y direction. The first vertical wall portion 75a of the first upper cover 75 and the second upper cover 76 The second vertical wall portion 76a is positioned with a predetermined gap, forming a connecting passage 80. In other words, the connecting passage 80 in Embodiment 1 is the gap between the first upper cover 75 and the second upper cover 76 in the X direction.

[0056] The connecting passage 80 opens into the recess 79a of the upper cover unit 79 and into the space S1 between the right side plate 73 and the left side plate 74, thereby connecting the outside and inside of the image forming apparatus 1. The connecting passage 80 is located below the output port 15 and directly above the developing process unit 20 and the scanner unit 50, which are located within space S1. As shown in Figure 6, in the paper output direction D2, the output tray 14 is located downstream of the connecting passage 80. In this embodiment, at least a portion of the connecting passage 80, at least a portion of the stacking portion of the output tray 14, and at least a portion of the output port 15 are located at the same position in the X direction. However, the position of the connecting passage 80 may differ from the position of the stacking portion of the output tray 14 and the position of the output port 15 in the X direction. A portion of the connecting passage 80, at least a portion of the loading section of the discharge tray 14, and at least a portion of the discharge port 15 may be located at the same position in the X direction, while the position of the other portion of the connecting passage 80 may differ from the position of the loading section of the discharge tray 14 and the position of the discharge port 15.

[0057] The lower end of the first vertical wall portion 75a of the first upper cover 75 is provided with a first canopy portion 75b that protrudes toward the second upper cover 76, and the upper end of the second vertical wall portion 76a of the second upper cover 76 is provided with a second canopy portion 76b that protrudes toward the first upper cover 75. Furthermore, the lower surface of the first vertical wall portion 75a of the first upper cover 75 and the lower surface of the base side of the second vertical wall portion 76a of the second upper cover 76 are substantially on the same plane.

[0058] A portion of the connecting passage 80 is formed by a first eaves portion 75b and a second eaves portion 76b located above the first eaves portion 75b. The first eaves portion 75b includes a first surface 75c facing upward, and the second eaves portion 76b includes a second surface 76c facing downward. In this embodiment, the first upper cover 75 and the second upper cover 76 are arranged such that, when viewed from above in the Z direction, a portion of the second eaves portion 76b overlaps with the first eaves portion 75b. Therefore, the first eaves portion 75b of the first upper cover 75 and the second eaves portion 76b of the second upper cover 76 are arranged to be staggered in the Z direction. Also, when viewed in the Z direction, the second surface 76c overlaps with the connection between the connecting passage 80 and the space S1. This configuration suppresses foreign matter such as dust in the air from entering the interior of the image forming apparatus 1 through the connecting passage 80. The application of the present invention is not limited to this configuration, and the connecting passage 80 may be configured such that the first canopy portion 75b is located above the second canopy portion 76b.

[0059] The intake port 403 of the blower unit 40 is located approximately directly below the outlet port 15, and is positioned closer to the upstream end of the recess 79a than to the downstream end in the paper discharge direction D2 of the recording material P at the outlet port 15. Also, as shown in Figures 1 and 6, the connecting passage 80 is closer to the upstream end 14a than to the downstream end 14b. In other words, according to the configuration of Embodiment 1, air can flow in towards the vicinity of the intake port 403 via the connecting passage 80.

[0060] Figure 8(c) is a cross-sectional view showing a different configuration example of the connecting passage 80 from Figure 8(b), and shows the positional relationship between the first upper cover 75 and the second upper cover 76. Figure 8(c) is a cross-sectional view of the upper cover unit 79 when viewed in the Y direction. In this example, the lower surface of the base side of the second vertical wall portion 76a of the second upper cover 76 is located below the lower surface of the first vertical wall portion 75a of the first upper cover 75.

[0061] The blower unit 40 draws in air from the space S1 between the right plate 73 and the left plate 74. Since the amount of air drawn in by the blower unit 40 is greater than the amount of air flowing in by the intake unit 300, the inside of the image forming apparatus 1 is under negative pressure, which is lower than the outside. Therefore, air flows in from the outside to the inside of the image forming apparatus 1 through the connecting passage 80. The air that has flowed into space S1 through the connecting passage 80 is then blown by the blower unit. Air is drawn in by unit 40. This configuration allows outside air to be drawn into the image forming apparatus 1, and the temperature of the air inside the image forming apparatus 1, which has been heated by various units, can be lowered.

[0062] Depending on the installation environment of the image forming apparatus 1, the air flowing in from the communication passage 80 may contain a large amount of foreign matter such as dust. Therefore, in Example 1, a filter 90 is provided in the communication passage 80 to allow air to pass through while preventing the intrusion of foreign matter such as dust.

[0063] In the configuration example shown in Figure 8(b), the filter 90 is provided at the end of the communication passage 80 on the device side. The filter 90 is provided so as to be in contact with the lower surface of the first vertical wall portion 75a of the first upper cover 75 and the lower surface of the base side of the second vertical wall portion 76a of the second upper cover 76, which are on substantially the same plane. The filter 90 is provided so as to cover the entire communication passage 80 when viewed in the cross-sectional direction of the communication passage 80 (the direction in which air flows), and captures foreign matter that attempts to enter the space S1.

[0064] In the configuration example shown in Figure 8(c), the filter 90 is installed inside the passageway 80. The filter 90 is installed so as to abut the tip of the first canopy portion 75b in the protruding direction (X direction) and the second vertical wall portion 76a. In this configuration example as well, the filter 90 is installed so as to cover the entire passageway 80 when viewed in the cross-sectional direction of the passageway 80, and captures foreign objects attempting to enter the space S1.

[0065] The filter 90 can be of various forms depending on the application. The material of the filter 90 can be, for example, sponge-like materials such as polyurethane foam, acrylic foam, or melamine foam, or nonwoven fabrics made of fibers such as cotton, polyethersulfone (PES), PET, or glass. Figure 8(b) shows an example where nonwoven fabric is used as the filter 90, and the filter 90 is attached to the first upper cover 75 and the second upper cover 76 from below. Figure 8(c) shows an example where sponge is used as the filter 90, and it is positioned to be in close contact with the front surface of the first visor portion 75b and the side surface of the second upper cover 76.

[0066] As described above, according to the configuration of Example 1, the filter 90 prevents the intrusion of foreign matter, while air can be drawn into the space S1 from outside the image forming apparatus 1 through the communication passage 80. Consequently, both the inside of the image forming apparatus 1 and the recording material P discharged from the outlet 15 can be cooled while suppressing the intrusion of dust into the space S1.

[0067] It should be noted that the configuration of Example 1 is merely an example and is not limited to such a configuration. For example, the communication passage 80 only needs to be located at the top of the image forming apparatus 1 and capable of allowing air to flow from the outside to the internal space S1, and the configuration of the communication passage 80 is not limited to that shown in Figures 8(b) and (c). Specifically, although the communication passage 80 was formed from one end in the X direction to the other end of the second upper cover 76, it may also be formed only on a part of the second upper cover 76, such as one end. Furthermore, the filter 90 only needs to allow air passing through the communication passage 80 to pass through and prevent the entry of foreign matter, and the configuration, material, and mounting method of the filter 90 are not limited to those shown in Figures 8(b) and (c).

[0068] Furthermore, in Example 1, the recording material P was discharged from the discharge port 15, which is the paper discharge section, and air from the blower unit 40 was also discharged. However, the configuration is not limited to this. For example, the paper discharge section may be composed of two or more openings, with a partition between the opening for discharging the recording material P and the opening for blowing air onto the recording material P.

[0069] (Example 2) Next, an embodiment 2 of the present invention will be described. Embodiment 2 is an upper cover unit 79 The configuration differs from that of Example 1. Below, only the differences between the configuration of Example 2 and that of Example 1 will be described. Components in Example 2 that are the same as those in Example 1 are denoted by the same reference numerals, and their descriptions are omitted.

[0070] [Configuration of the upper cover unit] Figures 10(a) and 10(b) show the configuration of the upper cover unit 79 and the communication passage 80 according to Embodiment 2. First, the configuration of the upper cover unit 79 according to Embodiment 2 will be explained using Figure 10(a). Figure 10(a) is a perspective view of the upper cover unit 79.

[0071] In Embodiment 2, the upper cover unit 79 is formed by a single upper cover 82. That is, the upper cover 82 has an upper surface portion integrally formed with a paper discharge section for discharging the recording material P, a stacking section on which the discharged recording material P is placed, and a recess 79a on which at least a part of the stacking section is located. The upper cover 82 is mounted on the right side plate 73 and the left side plate 74, and the recording material P is stacked sequentially on the stacking surface 78.

[0072] The upper cover unit 79 is provided with multiple communication passages 80 that connect the inside and outside of the image forming apparatus 1. In Embodiment 2, the communication passages 80 are through-holes with a circular cross-sectional shape that penetrate from the top surface to the bottom surface of the upper cover unit 79. The communication passages 80 are provided adjacent to both ends in the width direction (X direction) of the loading surface 78, and Figure 8(a) shows an example configuration in which four communication passages 80 are provided on one side. The communication passages 80 are also provided in the paper discharge direction D2 of the discharge port 15, closer to the upstream end than the downstream end of the recess 79a of the upper cover 82, that is, near the discharge port 15.

[0073] [Connection and filter configuration] Figure 10(b) is a cross-sectional view showing the configuration of the passage 80 according to Embodiment 2, and shows a cross-section of the upper cover unit 79. Figure 10(b) is a cross-sectional view of the upper cover unit 79 when viewed in the Y direction. In Embodiment 2 as well, when viewed in the cross-sectional direction of the passage 80 (Z direction in this example), the filter 90 is arranged to cover the entire passage 80. The filter 90 is provided so as to be in contact with the surface of the upper cover unit 79 where the passage 80 opens, and which faces downward in the Z direction.

[0074] In the configuration of Embodiment 2, the blower unit 40 draws in air, creating negative pressure inside the image forming apparatus 1, including the inside of the communication passage 80, causing air to flow in from the outside to the inside of the image forming apparatus 1. A filter 90 is also provided inside the communication passage 80 to prevent foreign matter such as dust contained in the air from entering. In this embodiment, the cross-sectional shape of the communication passage 80 was circular, but this is merely an example, and a different cross-sectional shape is also possible. Furthermore, in order to further enhance the foreign matter entry effect of the communication passage 80, the communication passage 80 may be configured to have a first surface and a second surface that face each other in the vertical direction, similar to Embodiment 1.

[0075] As described above, according to the configuration of this embodiment, the filter 90 prevents foreign matter from entering while air can be drawn into the space S1 from outside the image forming apparatus 1 through the communication passage 80. Consequently, dust can be prevented from entering the space S1 while both the inside of the image forming apparatus 1 and the recording material P discharged from the discharge port 15 can be cooled.

[0076] This embodiment includes the following configuration. (Composition 1) An image forming unit that forms an image on the recording material, A fixing unit that heats the recording material on which an image has been formed in the image forming unit, An outer casing that houses the image forming unit and the fixing unit, A paper discharge section from which the recording material heated in the fixing section is discharged, A stacking section on which the recording material discharged from the aforementioned paper discharge section is placed, An upper surface portion located above the image forming portion in the vertical direction and facing upward, including a recess that curves downward, in which at least a part of the loading portion is placed; A communication passage that connects the space in which the image forming unit is housed to the recess, An exterior part having, A blower unit having an exhaust port opening to the outside of the exterior part and an exhaust fan that generates an airflow from the space toward the exhaust port, Equipped with, An image forming apparatus characterized in that a filter is provided in the aforementioned communication passage. (Configuration 2) The loading section includes an upstream end and a downstream end with respect to the paper discharge direction of the recording material in the paper discharge section. The image forming apparatus according to configuration 1, characterized in that the communication passage is closer to the upstream end than to the downstream end. (Composition 3) The image forming apparatus according to configuration 2, characterized in that the loading section is inclined upward from the upstream end to the downstream end. (Composition 4) The image forming apparatus according to configuration 3, characterized in that the aforementioned passage is provided below the paper discharge section. (Composition 5) The device further comprises a first side plate and a second side plate arranged side by side in a direction intersecting the aforementioned paper discharge direction, The image forming apparatus according to any one of configurations 2 to 4, characterized in that the image forming unit, the fixing unit, and the blowing unit are arranged between the first side plate and the second side plate. (Composition 6) The image forming apparatus according to any one of configurations 1 to 5, characterized in that the aforementioned passageway is provided directly above the image forming section. (Composition 7) The image forming apparatus according to any one of configurations 1 to 6, characterized in that the aforementioned passage is formed by a first surface facing upward and a second surface facing downward. (Composition 8) The exterior part includes a first upper cover and a second upper cover, The image forming apparatus according to any one of configurations 1 to 7, characterized in that the aforementioned passage is the gap between the first upper cover and the second upper cover. (Composition 9) The image forming apparatus according to configuration 8, wherein the exterior part further includes a discharge tray including the loading part, and the discharge tray is swingable. (Composition 10) The aforementioned second upper cover has an opening, It is permissible to attach a toner supply container to the image forming unit through the aforementioned opening. The image forming apparatus according to configuration 9, characterized in that the discharge tray covers the opening. (Composition 11) The image forming apparatus according to any one of configurations 1 to 10, characterized in that the exterior portion includes an upper cover in which the paper discharge portion and the upper surface portion are integrally formed. (Composition 12) The image forming apparatus according to any one of configurations 1 to 11, characterized in that the blowing section includes a housing frame that houses the exhaust fan, and the housing frame has an air intake port that communicates with the space. (Composition 13) The image forming apparatus according to any one of configurations 1 to 12, characterized in that the exhaust fan generates an airflow from the exhaust port toward the recess. [Explanation of Symbols]

[0077] 1…Image forming apparatus, 9…Fixing apparatus (fixing section), 20…Developing process unit (image forming section), 40…Blower unit (blower section), 70…Exterior section, 79…Upper cover unit (top section), 79a…Recess, 80…Connecting passage, 90…Filter, 403…Intake port, 405…Exhaust fan, 412…Exhaust port, P…Recording material, S1…Space

Claims

1. An image forming unit that forms an image on the recording material, A fixing unit that heats the recording material on which an image has been formed in the image forming unit, An outer casing that houses the image forming unit and the fixing unit, A paper discharge section from which the recording material heated in the fixing section is discharged, A stacking section on which the recording material discharged from the aforementioned paper discharge section is placed, An upper surface portion located above the image forming portion in the vertical direction and facing upward, including a recess that curves downward, in which at least a part of the loading portion is placed; A communication passage that connects the space in which the image forming unit is housed to the recess, An exterior part having, A blower unit having an exhaust port opening to the outside of the exterior part and an exhaust fan that generates an airflow from the space toward the exhaust port, Equipped with, An image forming apparatus characterized in that a filter is provided in the aforementioned communication passage.

2. The loading section includes an upstream end and a downstream end with respect to the paper discharge direction of the recording material in the paper discharge section. The image forming apparatus according to claim 1, characterized in that the communication passage is closer to the upstream end than to the downstream end.

3. The image forming apparatus according to claim 2, characterized in that the loading section is inclined upward from the upstream end to the downstream end.

4. The image forming apparatus according to claim 3, characterized in that the aforementioned passage is provided below the paper discharge section.

5. The device further comprises a first side plate and a second side plate arranged side by side in a direction intersecting the aforementioned paper discharge direction, The image forming apparatus according to claim 2, characterized in that the image forming unit, the fixing unit, and the blowing unit are arranged between the first side plate and the second side plate.

6. The image forming apparatus according to claim 1, characterized in that the aforementioned passage is provided directly above the image forming section.

7. The image forming apparatus according to claim 1, characterized in that the aforementioned passage is formed by a first surface facing upward and a second surface facing downward.

8. The exterior portion includes a first upper cover and a second upper cover. The image forming apparatus according to claim 1, characterized in that the communication passage is the gap between the first upper cover and the second upper cover.

9. The image forming apparatus according to claim 8, wherein the exterior part further includes a discharge tray including the loading part, and the discharge tray is swingable.

10. The aforementioned second upper cover has an opening, It is permissible to attach a toner supply container to the image forming unit through the aforementioned opening. The image forming apparatus according to claim 9, characterized in that the discharge tray covers the opening.

11. The image forming apparatus according to claim 1, characterized in that the exterior portion includes an upper cover in which the paper discharge portion and the upper surface portion are integrally formed.

12. The image forming apparatus according to claim 1, wherein the blowing section includes a housing frame that houses the exhaust fan, and the housing frame is provided with an air intake port that communicates with the space.

13. The image forming apparatus according to claim 1, characterized in that the exhaust fan generates an airflow from the exhaust port toward the recess.

Images