JP6544199B2 - Exhaust device and image forming apparatus - Google Patents

Description

  The present invention relates to an exhaust system and an image forming apparatus. The image forming apparatus includes, for example, various types of apparatuses such as a copying machine, a printer, a facsimile machine, and a multifunction machine having a combination of these functions.

  In recent years, for example, UFP (Ultrafine Particle) generated from an image forming apparatus in Europe has become a problem. And it is becoming essential to collect UFP.

  Examples of UFP generation sources include those generated from the silicon roller of the fixing device and those generated from toner. As measures against these, there are a method of reducing the generation amount of UFP and a method of collecting the generated UFP with a filter.

  In the method of collecting UFPs with a filter, in order to collect UFPs efficiently, it is preferable to allow all generated UFPs to reach the filter through a duct without leakage. However, in the curved duct, the flow velocity is biased to the outer peripheral side of the curved shape, and the wind tends to leak from the duct bonding surface on the outer peripheral side. In order to avoid such problems, a structure is known in which the flow velocity of air including UFP inside the duct is made uniform so that the flow velocity does not increase locally (see, for example, Patent Document 1).

JP, 2012-169514, A

  However, the prior art disclosed in Patent Document 1 can not prevent the leakage of the exhaust gas at the outer periphery where the wind speed is high before passing through the filter.

  SUMMARY OF THE INVENTION The present invention is directed to preventing the leakage of exhaust gas without significantly increasing the layout space in an exhaust system having a curved shaped exhaust duct.

  An exhaust apparatus according to the present invention includes an exhaust duct through which exhaust gas flows, a dust collection fan for circulating the exhaust gas in the exhaust duct, and a filter member that collects dust contained in the exhaust gas. The exhaust duct includes a semicylindrical duct cover and a support member to which the duct cover is attached, and the duct cover has a curved shape as viewed from the duct cover attachment side of the support member. Further, the side wall outer surface is provided with a flange portion to be in contact with the support member, and the duct cover is provided in an inlet facing portion facing the inlet of the exhaust duct when viewed from the duct cover mounting side The protrusion direction dimension of the said collar part is larger than the protrusion direction dimension of the said collar part provided in the inner peripheral side curved part among the side walls of the inner peripheral side of the said curved shape

  In the exhaust system according to the present invention, for example, the contact area between the support member and the flange portion provided on the outer peripheral side wall of the curved shape of the duct cover is the above-mentioned contact side provided on the inner peripheral side wall. The contact area between the buttocks and the support member may be made larger. However, in the exhaust system according to the present invention, at least the projecting direction dimension of the flange portion in the inlet facing portion is larger than the projecting direction dimension of the flange portion provided on the side wall on the inner peripheral side. The size of the contact area does not matter on the outer circumferential side and the inner circumferential side.

  Further, in the exhaust system of the present invention, for example, the duct cover may be screwed to the support member using a screwing portion provided in the collar portion. However, in the exhaust system of the present invention, the method of attaching the duct cover to the support member may be a method other than screwing, and is not particularly limited.

  Furthermore, the number of the screwing points provided in the flange portion of the side wall on the outer peripheral side is more than the number of the screwing points provided in the flange portion of the side wall on the inner peripheral side. Can. However, in the exhaust system of the present invention, the number of screwing points may be the same on the outer circumferential side and the inner circumferential side, or the number of screwing spots may be larger on the inner circumferential side than on the outer circumferential side.

  Further, the projecting direction dimension of the flange portion at the screwing portion provided at the flange portion of the side wall on the inner peripheral side is provided at another portion of the flange portion provided at the side wall on the inner peripheral side There can be mentioned an example in which the dimension in the projecting direction of the flange portion is larger. However, in the exhaust system of the present invention, the dimension in the projection direction of the ridge at the screwing portion on the inner circumferential side may be the same as the dimension in the projection direction of the ridge on the other circumferential side.

  Further, in the exhaust device of the present invention, for example, a side wall end of the side wall of the duct cover on the side of the support member protrudes to the side of the support member rather than the ridge, and between the sidewall and the ridge With regard to the projecting dimension of the second, the projecting dimension at the inlet facing portion may be larger than the projecting dimension at the inner circumferential side. However, in the exhaust system of the present invention, the projecting dimension at the inlet facing portion may be the same as or smaller than the projecting dimension at the inner circumferential side.

  Further, in the exhaust system of the present invention, for example, regarding the side wall height dimension of the side wall on the outer peripheral side of the duct cover, the side wall height dimension at the inlet facing portion is the flow as seen from the duct cover attachment side. It may be made to be larger than the above-mentioned side wall height size in a portion on the downstream side of the exhaust gas flow than the inlet facing portion. However, in the exhaust system of the present invention, the side wall height dimension in the inlet facing portion may be the same as or smaller than the side wall height dimension in the downstream side portion.

  Furthermore, in the side wall on the outer peripheral side of the duct cover, a stepped portion is provided between the inflow facing portion and the downstream portion, and the stepped portion is disposed at a distance from the inflow facing portion. An example can be given. However, the stepped portion may be adjacent to the inlet facing portion.

  An image forming apparatus according to the present invention is an image forming apparatus provided with a fixing unit for fixing the toner image on a recording material to which a toner image has been transferred in an apparatus main body, the air around the fixing unit being the device The exhaust system according to the present invention for exhausting from the body of the present invention is provided.

  In the image forming apparatus of the present invention, the exhaust duct of the exhaust device may be provided, for example, in a door which also serves as a conveyance path of the recording material provided on the exterior of the apparatus main body. However, in the image forming apparatus of the present invention, the arrangement position of the exhaust duct is not limited to the door.

  Further, in the image forming apparatus of the present invention, the exhaust device may be attached to the main body of the apparatus so that the side wall on the inner peripheral side faces the fixing device. However, in the image forming apparatus of the present invention, the positional relationship between the exhaust device and the fixing device is not limited to this.

  In the exhaust system according to the present invention, the flange portion of the duct cover to be in contact with the support member is provided in the side wall of the duct cover at the inlet facing portion facing the inlet of the exhaust duct when viewed from the duct cover mounting side of the support member. The projecting direction dimension of the collar portion is larger than the projecting direction dimension of the collar portion provided on the inner peripheral curved portion of the side wall on the inner peripheral side. Thus, the exhaust system of the present invention can prevent the leakage of the exhaust gas without significantly increasing the installation space. Consequently, the exhaust system of the present invention can enhance the collection effect of the particulates contained in the exhaust gas.

  In the exhaust system of the present invention, the contact area between the support member and the flange portion provided on the outer peripheral side wall of the curved shape of the duct cover is the flange portion provided on the inner peripheral side wall If the area of contact with the support member is made larger, the leakage of the exhaust gas on the outer peripheral side where the flow velocity of the exhaust gas is large can be more effectively prevented.

  Further, in the exhaust system according to the present invention, for example, if the duct cover is screwed to the support member using the screwing portion provided on the collar portion, the lower surface of the duct portion on the flange portion and the support are supported. The degree of close contact with the member can be improved to prevent the leakage of the exhaust gas.

  Further, the number of screwing points provided in the flange portion of the outer peripheral side wall is greater than the number of screwing points provided in the flange portion of the inner peripheral side wall If so, it is possible to more effectively prevent the leakage of the exhaust gas on the outer peripheral side where the flow velocity of the exhaust gas is high.

  Further, the projecting direction dimension of the flange portion at the screwing portion provided at the flange portion of the side wall on the inner peripheral side is provided at another portion of the flange portion provided at the side wall on the inner peripheral side If it is made larger than the dimension in the projection direction of the flange portion, screwing of the duct cover can be performed without significantly increasing the area of the flange portion on the inner peripheral side. Thereby, the arrangement area of the duct cover can be made as small as possible, and the limited space can be effectively used for other applications.

  Further, in the exhaust system according to the present invention, the side wall end of the side wall of the duct cover on the side of the support member protrudes to the side of the support member rather than the ridge portion, and the protrusion between the sidewall end portion and the ridge portion With regard to dimensions, if the protrusion dimension at the inlet facing portion is larger than the protrusion dimension at the inner circumferential side wall, leakage of exhaust gas at the inlet facing portion is more effectively prevented. it can.

  Further, in the exhaust system according to the present invention, regarding the side wall height dimension of the side wall on the outer peripheral side of the duct cover, the side wall height dimension at the inlet facing portion is the inlet facing as viewed from the duct cover mounting side. If the side wall height dimension of the downstream portion of the exhaust gas flow is larger than the portion, leakage of the exhaust gas at the inlet facing portion can be more effectively prevented.

  Furthermore, in the side wall on the outer peripheral side of the duct cover, a stepped portion is provided between the inflow facing portion and the downstream portion, and the stepped portion is disposed at a distance from the inflow facing portion. If this is done, it is possible to prevent the leakage of the exhaust gas at the step portion where the possibility of the exhaust gas leaking is higher than in the other portions.

  The image forming apparatus according to the present invention includes the exhaust device according to the present invention for discharging the air around the fixing unit to the outside of the apparatus main body, so that the leakage of the exhaust gas including UFP generated around the fixing unit is prevented. Thus, the UFP collection effect can be improved.

  Further, in the image forming apparatus of the present invention, if the exhaust duct of the exhaust device is provided, for example, on a door which also serves as a conveyance path of the recording material provided on the exterior of the apparatus main body, An exhaust duct can be disposed within the limited space of the image forming apparatus.

  Further, in the image forming apparatus according to the present invention, the image forming apparatus may be configured such that the exhaust duct of the exhaust device is attached to the main body of the apparatus so that the side wall on the inner peripheral side faces the fixing device. The exhaust duct can be arranged in a limited space of

FIG. 2 is a schematic external perspective view of an MFP. It is rough front sectional drawing which shows the internal structure of an apparatus main body. It is a schematic left side view showing the structure of an exhaust duct. It is a schematic left side view showing arrangement of an exhaust duct in an upper right door. FIG. 4 is a schematic cross-sectional view of the exhaust duct at the A-A position in FIG. 3; FIG. 4 is a schematic cross-sectional view of the exhaust duct at position B-B in FIG. 3; It is a schematic left sectional view showing the channel division structure of a duct cover. It is a schematic perspective view showing an exhaust duct. It is a schematic perspective view which shows the state which the upper right door opened.

  Hereinafter, an embodiment of the present invention will be described based on the drawings (FIGS. 1 to 9). In the following description, when using terms (for example, “left and right”, “upper and lower”, etc.) to indicate a specific direction or position as necessary, the direction orthogonal to the paper surface in FIG. I have to. These terms are used for the convenience of description and do not limit the technical scope of the present invention.

(1). Overview of MFP A multifunction device 1 (hereinafter referred to as an MFP) as an example of an image forming apparatus shown in FIG. 1 has many functions such as a copy function, a scanner function, a printer function, and a fax function. The MFP 1 can transmit and receive data via a network (communication network) such as a LAN or a telephone line, for example. That is, MFP 1 outputs image data read from a document to another computer via a network, inputs image data from another computer via network, and executes printing based on the image data It can be sent and received.

  An image reading unit 5 including a scanner unit 3 and an automatic document conveyance unit 4 (hereinafter referred to as an ADF) is provided on the top of the apparatus main body 2 constituting the MFP 1. The image reading unit 5 is configured to operate the scanner unit 3 and the ADF 4 in synchronization with each other and optically read an image from each of the originals set in the ADF 4 to acquire image data. That is, the ADF 4 transports the document sheet by sheet to the scanner unit 3, and the scanner unit 3 is configured to read an image and acquire image data when the document passes a predetermined reading position. .

  At a lower portion of the apparatus main body 2, a sheet feeding unit 7 that accommodates the recording material P is provided. An image forming unit 6 for printing a toner image on the recording material P is provided between the image reading unit 5 and the paper feeding unit 7 in the apparatus main body 2. The sheet feeding unit 7 supplies the recording material P to the image forming unit 6 one by one, and the image forming unit 6 prints a toner image on the recording material P based on the image data acquired via the image reading unit 5 or the network. It is configured to A recessed space between the image reading unit 5 and the image forming unit 6 in the apparatus body 2 is a discharged sheet storage unit 8. The recording material P on which the toner image is printed by the image forming unit 6 is discharged to the paper discharge storage unit 8.

  An operation panel 9 having a plurality of keys (buttons) is provided on the front side (front side) of the apparatus body 2. The user can perform setting operation for the function selected from among the various functions of the MFP 1 or instruct the MFP 1 to perform work by performing key operation while viewing the display screen of the operation panel 9 or the like.

  In the left and right side portions (the left side portion in the embodiment) of the apparatus main body 2, rectangular openings 11 and 51 arranged in two upper and lower stages are formed. The upper left opening 11 is closed by an upper right door 12 which can be opened and closed up and down centering on a rotation fulcrum 13 (see FIG. 2) on the lower end side. Further, the lower left opening 51 is closed by a lower right door 52 which can be opened and closed up and down centering on a rotation fulcrum 53 (see FIG. 2) on the lower end side. The axial direction of the pivot point parts 13 and 53 of the doors 12 and 52 extends in the front-rear horizontal direction. Although the detailed illustration is omitted, the front opening formed in the front side of the apparatus main body 2 is closed by the front door 14 which can be pivoted up and down with the lower end side as a pivot. The opening and closing of the doors 12, 14, 52 exposes or covers the inside of the apparatus body 2. At the time of jam processing and consumables replacement, the doors 12, 14, 52 are opened, and a hand is externally inserted into the inside of the apparatus main body 2 to perform various operations.

(2). Internal Structure of Device Body Next, the internal structure of the device body 2 will be described with reference to FIG. The recording material P fed out from the paper feeding unit 7 is conveyed to the image forming unit 6 along the conveyance path 15. In the image forming unit 6, a toner image consisting of four colors of yellow (Y), magenta (M), cyan (C), and black (K) is primarily transferred onto the intermediate transfer belt 16, and the recording material P transfers the transfer portion 17. When passing, the toner images on the intermediate transfer belt 16 are collectively secondarily transferred onto one side of the recording material P. The recording material P on which the unfixed toner image is placed on one side is heated and pressurized when passing through the fixing device 18, and the unfixed toner image is fixed. The recording material P having the toner image fixed thereon is discharged from the paper discharge port 19 to the paper discharge storage section 8.

  Above the intermediate transfer belt 16, a plurality of toner bottles 56 for containing the replenishment toner are detachably disposed. The toner bottle 56 has four colors of yellow, magenta, cyan and black depending on the reproduced color. The replenishment toner of each toner bottle 56 is supplied to each developing device of the image forming unit 6. Although not shown in detail, a waste toner container for storing waste toner (non-transfer toner) removed from the intermediate transfer belt 16 or the like is detachably disposed in the vicinity of the image forming unit 6. .

  The scanner unit 3 of the image reading unit 5 in the upper part of the apparatus body 2 has a document table 61 having a platen glass (not shown) on the upper surface side, a light source device 63 for irradiating light to the document D, and the document D Sensor 64 for photoelectrically converting the reflected light from the image to an image signal, the imaging lens 65 for imaging the reflected light on the image sensor 64, and the reflected light from the document D sequentially reflected and incident on the imaging lens 65 And a mirror group 66. The light source device 63, the image sensor 64, the imaging lens 65, and the mirror group 66 are provided inside the document table 61.

  When reading the document D on the platen glass, the light source device 63 applies light to the document D while moving the light source device 63 and the mirror group 66 in the left-right direction of the apparatus main body 2. The reflected light reflected from the original D is sequentially reflected by the mirror group 66 and is incident on the imaging lens 65 to be imaged on the image sensor 64. The image sensor 64 performs photoelectric conversion for each pixel according to the intensity of incident light, and generates an image signal (RGB signal) corresponding to the image of the document D. The image signal (RGB signal) is output to the controller 30 described later.

  The ADF 4 is provided on the upper surface side of the document table 61 so as to be openable and closable. The ADF 4 also has a function of bringing the document D into close contact with the platen glass by covering the document D on the platen glass. The ADF 4 includes a document placement tray 67 and a document discharge tray 68. When reading the document D placed on the document placement tray 67, the document D is conveyed to the reading position by the document conveyance mechanism 62 constituted by a plurality of rollers and the like. At this time, light is irradiated from the light source device 63 to the reading position portion of the document D, and the reflected light is imaged on the image sensor 64 through the mirror group 66 and the imaging lens 65. Then, the image sensor 64 converts it into an image signal (RGB signal) corresponding to the image of the document D, and outputs the image signal to the controller 30. Thereafter, the document D is discharged to the document discharge tray 68. The document placement tray 67 is provided with an ADF document detection sensor 69 for detecting the presence or absence of the document D on the document placement tray 67. An ADF open / close sensor (not shown) for detecting the open / close state of the ADF 4 is disposed at the rotation fulcrum of the ADF 4.

  As shown in FIG. 2, the inner surface of the upper right door 12 on the conveyance path 15 side functions as part of the conveyance path 15 in a state where the upper right door 12 is closed. The upper right door 12 is unitized in a state in which the secondary transfer roller 21 of the transfer unit 17 and one of the pair of registration rollers 22 on the conveyance upstream side of the transfer unit 17 are assembled. By the opening and closing rotation of the upper right door 12, the range on the conveyance downstream side after the registration roller pair 22 in the conveyance path 15 is exposed or covered. That is, the upper left opening 11 closed by the upper right door 12 faces the conveyance downstream side of the conveyance path 15 (a place near the transfer unit 17 and the fixing device 18). The lower left opening 51 closed by the lower right door 52 faces the conveyance upstream side of the conveyance path 15 (a part near the sheet feeding unit 7). Although the detailed illustration is omitted, the front opening closed by the front door 14 is a toner bottle 56 of each color of yellow (Y), magenta (M), cyan (C), black (K) and waste It faces the toner container etc.

(3). Related Structure of Exhaust Duct An exhaust device 71 is provided on the back side (rear side) of the upper right door 12. The exhaust device 71 includes exhaust ducts 72 and 73 through which the exhaust gas flows, a dust collection fan 74 for circulating the exhaust gas in the exhaust ducts 72 and 73, and a dust collection filter that collects dust contained in the exhaust gas. And 75 (filter member).

  The exhaust duct 72 connects the exhaust port of the dust collection fan 74 and the inlet of the exhaust duct 73. A dust collection filter 75 is disposed to face the discharge port of the exhaust duct 73. Although the aspect of the dust collection fan 74 is not limited to a specific one, in the present embodiment, it is a centrifugal fan type sirocco fan.

  The exhaust ducts 72, 73 include semi-cylindrical duct covers 72a, 73a, and a support member 76 into which the lower end portions of the side walls of the duct covers 72a, 73a are inserted and the duct covers 72a, 73a are attached. The support member 76 doubles as a base material of the upper right door 12, for example. The duct covers 72a and 73a are provided with respective ridges 77 on the outer surface of the side wall. The flange portion 77 limits the amount of insertion of the duct covers 72 a and 73 a into the support member 76 and is in contact with the support member 76.

  The duct cover 73a has a curved shape as viewed from the upper surface 73f side (the duct cover mounting side of the support member 76). The duct cover 73a has an inflow port 73b having one side wall surface opened, an outer peripheral side wall 73c having a curved shape, an inner peripheral side wall 73d having a curved shape, and an end opposite to the inflow port 73b. A downstream end wall 73e of the section.

  As shown in FIG. 3, in the curved exhaust duct 73, the flow of the exhaust gas is concentrated on the side wall 73c on the outer peripheral side of the exhaust duct 73, and the exhaust gas flows on the side wall 73d on the inner peripheral side Hateful. Therefore, the exhaust gas easily leaks from the side wall 73c on the outer peripheral side where the flow velocity of the exhaust gas is large.

In this embodiment, in the duct cover 73a, the projection direction dimension W _77c of the ridge portion 77 at the inlet facing portion 78 facing the inlet of the exhaust duct 73 which is a part of the side wall 73c on the outer peripheral side and faces the upper surface 73f. Is larger than the projection direction dimension W 77 _d of the flange portion 77 provided on the inner peripheral side curved portion 87 which is the side wall _{73 d} on the inner peripheral side and which is curved (see FIGS. 3 and 6). That is, regarding the contact area of the flange portion 77 and the support member 76, the inlet facing portion 78 is larger than the inner curved portion 87 of the inner side wall 73d. As a result, the exhaust device 71 can prevent the leakage of the exhaust gas without significantly increasing the arrangement space. As a result, the exhaust device 71 can enhance the collection effect of particulates contained in the exhaust gas.

  Further, in the exhaust device 71, the contact area between the flange portion 77 provided on the outer peripheral side wall 73c and the support member 76 is larger than the contact area between the flange portion provided on the inner peripheral side wall 73d and the support member Is also getting bigger. This makes it possible to more effectively prevent the leakage of the exhaust gas on the outer peripheral side where the flow velocity of the exhaust gas is high.

  Further, the duct covers 72a and 73a are screwed to the support member 76 by screws 79 using screwing points provided on the flange portion 77. As a result, the degree of close contact between the lower surface of the flange 77 of the duct cover 72a, 73a and the support member 76 can be improved, and the leakage of the exhaust gas can be prevented.

  Further, the number (for example, five) of screwing locations in the flange portion 77 provided on the outer peripheral side wall 73c is the number of screwing locations on the inner peripheral side wall 73d (for example, 4 locations) It is more than). Thus, the exhaust device 71 can more effectively prevent the leakage of the exhaust gas on the outer peripheral side where the flow velocity of the exhaust gas is high.

  Further, regarding the dimension in the projection direction of the flange portion 77 provided on the side wall 73d on the inner peripheral side, the dimension in the projection direction of the flange portion 77 at the screwing point is larger than the dimension in the projection direction at other portions. Thus, the duct cover 73a can be screwed without significantly increasing the area of the flange portion 77 provided on the side wall 73d on the inner peripheral side. Thereby, the arrangement area of the duct cover 73a can be made as small as possible, and the limited space can be effectively used for other applications.

Further, in the exhaust device 71, regarding the protrusion dimension between the lower end surface of the side walls 73c and 73d in the duct cover 73a and the lower surface of the flange portion 77, the protrusion dimension D _73c of the side wall 73c on the outer peripheral side in the inlet facing portion 78 is The projection dimension D ₇₃ d of the circumferential side wall 73 d is larger than the projection dimension D ₇₃ d (see FIG. 6). Thus, the exhaust device 71 can more effectively prevent the leakage of the exhaust gas at the inlet facing portion 78.

Further, regarding the side wall height dimension between the upper surface 73 f of the duct cover 73 a and the upper surface of the brim portion 77 in the side wall 73 c on the outer peripheral side of the duct cover 73 a in the exhaust device 71, the side wall height dimension H at the inlet facing portion 78 ₇₈ is larger than the side wall height H ₈₀ at the downstream portion 80 of the exhaust gas flow than the inlet facing portion 78 when viewed from the upper surface 73 f side. Thus, the exhaust device 71 can more effectively prevent the leakage of the exhaust gas at the inlet facing portion 78.

  Furthermore, in the side wall 73c on the outer peripheral side of the duct cover 73a, a stepped portion 81 is provided between the inlet facing portion 78 and the downstream portion 80. The stepped portion 80 is disposed at a distance from the inlet facing portion 78. Thus, the exhaust device 71 can prevent the leakage of the exhaust gas at the step portion where the possibility that the exhaust gas leaks is higher than in the other portions.

  Further, since the MFP 1 is provided with the exhaust device 71 for exhausting the air around the fixing device 18 to the outside of the apparatus main body 2, the leakage of the exhaust gas including the UFP generated around the fixing device 18 is prevented Thus, the UFP collection effect can be improved.

  Further, the exhaust ducts 72 and 73 of the exhaust device 71 are provided in the upper right door 12 which also serves as the conveyance path 15 of the recording material D provided on the exterior of the apparatus main body 2. The exhaust ducts 72, 73 can be arranged at the same time, so that the exhaust device 71 can be arranged.

  In addition, if the exhaust duct 73 of the exhaust device 71 is attached to the main body of the apparatus so that the side wall 73 d on the inner circumferential side faces the fixing device 18, the exhaust duct 73 exhausts into the limited space of the image forming apparatus. A duct can be arranged.

  Further, in the apparatus main body 2, a partition member 82 surrounding the fixing device 18 is provided. An exhaust device 71 is attached on the right side of the partition member 82, and the right side of the fixing device 18 is covered with the partition member 82 and the exhaust device 71. As described above, when the partition member 82 surrounding the fixing device 18 is provided, dust floating around the fixing device 18 is a portion of the apparatus main body 2 other than the fixing device 18 (for example, the image forming unit 6 or It can be easily prevented from leaking to the paper portion 7 or the like.

  When the dust collection fan 74 is rotated (driven), the air in the partition member 82 (around the fixing device 18) flows from the left to the right and is sucked into the dust collection fan 74 of the exhaust device 71 and exhausted through the exhaust duct 72. It is discharged from the outlet of the duct 73. Thereafter, the exhaust gas passes through the dust collection filter 75 and is exhausted out of the apparatus main body 2. Dust in the air is collected by the dust collection filter 75. The air from the inside of the partition member 82 toward the exhaust port also plays a role as an exhaust heat mechanism that takes heat around the fixing device 18. Further, the dust collection fan 74 is provided so as to suction the non-transfer surface side of the recording material P passing between the transfer portion 17 and the fixing device 18.

  As shown in FIGS. 6 and 7, the duct cover 73a of the exhaust device 71 includes a plurality of flow straightening plates 83a, 83b, 83c that divide the flow path from the inflow port 73b to the downstream side wall 73e into a plurality. The flow passage in the exhaust duct 73 is divided into four divided flow passages 84A, 84B, 84C, 84D. The respective flow control plates 83a, 83b, 83c are in contact with the inner surface of the duct cover 73a. The divided flow paths 84A, 84B, 84C, and 84D are respectively independent flow paths from the inflow port 73b to the downstream side wall 73e.

(4). Arrangement of Upper Right Door Support Wire and Spring As shown in FIGS. 2 and 9, a spring 85 and a wire 86 for supporting the upper right door 12 are provided. The spring 85 is constituted of, for example, two coiled tension springs. The spring 85 is disposed on a cover plate 88 that covers the top of the toner bottle 56. One end of the spring 85 is supported on the front side of the device body 2 by a fixture attached to the upper surface of the cover plate 88.

  The other ends of the two springs 85 are connected to one end of one wire 86 via a connector on the cover plate 88. The other end of the wire 86 is attached to the inner surface side of the upper right door 12 at a position lower than the exhaust duct 73 and the dust collection filter 75 of the exhaust device 71 in a state where the upper right door 12 is closed, for example. The wire 86 is guided from the spring 85 side to the upper right door 12 along a slippery guide provided on the back side of the apparatus main body 2 and a plurality of pulleys (not shown).

  A document discharge tray 68 is disposed above the cover plate 88. The document discharge tray 68 is detachably attached to the apparatus body 2 by, for example, two screws. Since the spring 85 and one end of the wire 86 can be exposed by removing the document discharge tray 68, the maintenance workability of the spring 85 and the wire 86 is improved.

(5). Others The present invention is not limited to the above embodiment, and can be embodied in various aspects. For example, although the MFP 1 has been described as an example of the image forming apparatus, the present invention is not limited to this and may be a printer or the like. In addition, the configuration of each part is not limited to the illustrated embodiment, and various modifications can be made without departing from the spirit of the present invention.

1 MFP (image forming device)
2 Main unit 12 Upper right door (door)
18 Fixing part 73 Exhaust duct 73a Duct cover 73b Inflow port 73c Side wall 73d on the outer peripheral side Side wall 73f on the inner peripheral side Upper surface of duct cover 74 Dust collection fan 75 Filter (filtration member)
76 support member 77 ridge portion 78 inlet facing portion 79 screw 81 step portion 87 inner circumferential curved portion P recording material

Claims (11)

An exhaust duct through which exhaust gas flows;
A dust collection fan for circulating the exhaust gas in the exhaust duct;
And a filter member for collecting dust contained in the exhaust gas,
The exhaust duct includes a semi-cylindrical duct cover and a support member to which the duct cover is attached.
The duct cover has a curved shape as viewed from the duct cover mounting side of the support member, and includes a ridge on the side wall outer surface that is in contact with the support member.
In the duct cover, the projecting direction dimension of the ridge portion provided in the inlet facing portion facing the inlet of the exhaust duct as viewed from the duct cover mounting side in the side wall has an inner periphery of the curved shape An exhaust system characterized in that it is larger than the dimension in the projection direction of the flange portion provided on the inner peripheral side curved portion of the side wall.   The contact area between the support member and the flange portion provided on the outer peripheral side wall of the curved shape of the duct cover is the contact between the flange portion provided on the inner peripheral side wall and the support member The exhaust system according to claim 1, which is larger than the area.   The exhaust system according to claim 1 or 2, wherein the duct cover is screwed to the support member using a screwing portion provided in the collar portion.   The number of the screwing points provided in the flange portion of the outer peripheral side wall is greater than the number of the screwing points provided in the flange portion of the inner peripheral side wall. Exhaust system as described in.   The projecting direction dimension of the flange portion at the screwing point provided at the flange portion of the side wall on the inner peripheral side is provided at the other portion of the flange portion provided on the side wall on the inner peripheral side The exhaust system according to claim 3 or 4, which is larger than the projecting direction dimension of the flange. The side wall end of the side wall of the duct cover on the side of the support member protrudes to the side of the support member relative to the flange portion,
The protrusion dimension in the inflow inlet opposing part is larger than the protrusion dimension in the side wall on the inner peripheral side with respect to the protrusion dimension between the side wall end and the ridge portion. Exhaust system according to one of the claims.   Regarding the side wall height dimension of the side wall on the outer peripheral side of the duct cover, the side wall height dimension at the inlet facing portion is a downstream side of the exhaust gas flow than the inlet facing portion viewed from the duct cover mounting side 7. An exhaust system according to any one of the preceding claims, wherein the side wall height dimension in the part of (1) is greater. In the side wall on the outer peripheral side of the duct cover, a stepped portion is provided between the inlet facing portion and the downstream portion,
The exhaust system according to claim 7, wherein the stepped portion is disposed at a distance from the inlet facing portion. An image forming apparatus comprising a fixing unit for fixing the toner image on a recording material to which a toner image has been transferred, in an apparatus main body, comprising:
An image forming apparatus comprising the exhaust device according to any one of claims 1 to 8, which discharges air around the fixing unit to the outside of the apparatus main body.   The image forming apparatus according to claim 9, wherein the exhaust duct of the exhaust device is provided on a door which also serves as a conveyance path of a recording material provided on an exterior of the apparatus main body.   The image forming apparatus according to claim 9, wherein the exhaust duct of the exhaust device is attached to the apparatus main body such that a side wall on the inner circumferential side faces the fixing device.

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