JP2015132856A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively cool the inside of a body housing of an image forming device.SOLUTION: An operating portion housing 21 is protrusively provided on an upper part of a front wall 12W of a right strut portion 12, along a front surface 10F of a body housing 11. Near an upper surface of the operating portion housing 21, an operation panel 20P and an electric circuit substrate 20B are housed in the operating portion housing 21, and an intake air port 22 is provided on a lower surface of the operating portion housing 21. An upper part of the intake air port 22 is covered with a duct 23. When a cooling fan 60 is actuated, an air flow entering the body housing 11 from the intake air port 22 is generated. Air taken in through the intake air port 22 enters an air passage 23H covered with the duct 23, and reaches an inner space 211 of the operating portion housing 21. The air is lead to an inner space 101 in the body housing 11 through a communicating portion 212.

Description

  The present invention relates to an image forming apparatus that forms an image on a sheet, and more particularly to an image forming apparatus including a cooling fan in a main body housing.

  The image forming apparatus includes many heat generating elements. For example, the fixing unit fixes the toner image on the sheet by heating and pressing the sheet on which the toner image is transferred. Accordingly, the periphery of the fixing unit and the sheet subjected to the fixing process are heated. Here, when the moisture content of the sheet is high, water vapor may be generated from the sheet. In this case, there may be a problem that the user misidentifies the water vapor as fuming or the water vapor condenses on the sheet conveyance path.

  In order to solve the above-described problem, Patent Document 1 discloses an image forming apparatus in which a cooling fan is disposed on a support column on the side of the in-body discharge unit. The post portion is provided with a sheet discharge port oriented to the in-body discharge portion and a fixing portion. The sheet and the fixing unit are cooled by the air flow generated by the cooling fan. The air going into the apparatus is taken in from a louver (intake port) provided on the front cover of the support column that does not face the in-body discharge section. Therefore, relatively cool air can be taken into the apparatus instead of the air in the in-body sheet discharge section warmed by the discharge of the sheet.

JP 2010-072042 A

  According to the image forming apparatus of Patent Document 1, the cooling fan is disposed on the back surface of the front cover having a louver. In order to efficiently perform the equipment in the apparatus, it is necessary to provide a certain space in the apparatus. In addition, when the distance between the louver and the cooling fan is short, an air flow is often not generated stably even when the cooling fan is operated. That is, the intended amount of air often cannot be taken into the device. For this reason, in the image forming apparatus of Patent Document 1, it is necessary to take a large space on the back surface of the front cover, which causes a problem that the downsizing of the image forming apparatus is hindered and the appearance is impaired.

  An object of the present invention is to provide an image forming apparatus capable of efficiently cooling the inside of a main body housing.

  An image forming apparatus according to one aspect of the present invention is a housing including an image forming unit that performs image forming processing on a sheet and a front surface, and includes a first internal space in the housing that houses the image forming unit. A small housing including a first housing, an upper surface and a lower surface, and protruding from the front surface of the main body housing, the small housing having a second internal space communicating with the first internal space; A fan disposed in the first internal space for generating an air flow, an intake port formed on the lower surface of the second housing for taking in air when the fan is operated, and an upper portion of the intake port A duct disposed in the second internal space so as to cover; and an opening that allows communication between the space covered by the duct and the second internal space. A first standing wall extending in the direction and having a discharge port for discharging the image-formed sheet to the outside, and a second standing wall extending in the left-right direction and extending along the front surface of the first housing. A projecting housing portion projecting from the first standing wall, and a sheet tray for receiving the sheet discharged from the discharge port, wherein the second housing projects from the second standing wall. And a left side surface portion extending forward along the first standing wall.

  According to this configuration, the air inlet is provided on the lower surface of the second housing, and when the fan is operated, air is guided into the first internal space via the air inlet and the duct. For this reason, the distance and space between the fan arrange | positioned in the said 1st internal space and the said air inlet can fully be taken, without forming extra space in the 1st housing. As a result, the inside of the first housing can be efficiently cooled and a stable air flow can be generated. Further, since the upper portion of the air inlet is covered with the duct, a user touches the electric circuit board through the air inlet, or a fallen object from the electric circuit board comes out through the air inlet. Can be prevented. Furthermore, an air flow can be generated in the second internal space through the opening.

  The first housing extends in the front-rear direction and has a first standing wall formed with a discharge port for discharging the image-formed sheet to the outside. The first housing extends in the left-right direction and extends along the front surface of the first housing. A projecting housing portion that protrudes upward, and a sheet tray that is adjacent to the first standing wall and receives the sheet discharged from the discharge port, wherein the second housing includes the second standing wall. It protrudes from the standing wall, and includes a left side surface portion that extends forward along the first standing wall.

  Since the sheet immediately after the fixing process is discharged to the sheet tray, warm air is likely to be generated around the sheet tray. Such warm air is not suitable for cooling in the main body housing. According to the above configuration, the second housing is disposed at a position separated from the sheet tray. Therefore, relatively cool air can be taken in from the air inlet provided on the lower surface of the second housing.

  The said structure WHEREIN: The said duct is provided with the top | upper surface piece which opposes the said upper surface of the said 2nd housing, and several side piece which supports the said top | upper surface piece, The said opening part is provided in the said some side piece. It is desirable that

  The duct includes a top piece facing the top surface of the second housing, and a side piece supporting the top piece, and the opening is a hole drilled in the top piece. It is desirable.

  The ducts according to these configurations have a function of reliably covering the upper portion of the intake port and are provided with the opening. Therefore, the configuration of the duct and the opening can be simplified.

  The said structure WHEREIN: It is desirable for the said top surface piece to have an area larger than the said electric circuit board, and to arrange | position the said electric circuit board above the area | region divided by the periphery of the said top surface piece.

  According to this configuration, since the top piece has a larger area than the electric circuit board, the above-described contact of the user with the electric circuit board and the prevention of falling objects from the electric circuit board are further improved. It can be done reliably.

  The said structure WHEREIN: It is desirable that the said duct consists of a sheet metal member. According to this configuration, the duct can be easily formed by punching and bending the sheet metal member. Moreover, even if the resin melt may fall from the electric circuit board, it can be received without problems by the duct.

  According to the present invention, it is possible to provide an image forming apparatus capable of efficiently cooling the first housing.

1 is a perspective view of an image forming apparatus according to an embodiment of the present invention. FIG. 3 is a perspective view of the image forming apparatus with different perspective directions. It is sectional drawing which shows the internal structure of the said image forming apparatus. It is a cross-sectional perspective view of the vicinity of the operation unit of the image forming apparatus. It is a perspective view of the operation part of 1st Embodiment. It is the perspective view of the operation part of 1st Embodiment, Comprising: It is the figure which varied the perspective direction. It is a perspective view of the duct of a 1st embodiment. It is a top view of the duct of a 1st embodiment. It is a perspective view of the operation part containing the duct of 2nd Embodiment. It is a perspective view of the duct of a 2nd embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of an image forming apparatus 1 according to an embodiment of the present invention as viewed from the upper left side, and FIG. 2 is a perspective view of the same image forming apparatus 1 as viewed from the lower right side. . Here, a printer is exemplified as the image forming apparatus 1, but the image forming apparatus may be a copier, a facsimile machine, or a multifunction machine having these functions.

  The image forming apparatus 1 includes an apparatus main body 10 having a substantially rectangular parallelepiped housing structure including a front surface 10F, a left side surface 10L, a right side surface 10R, and a rear surface 10B. The apparatus main body 10 includes a main body housing 11 (first housing), a right column portion 12 (projecting housing portion) erected on the upper right portion of the main body housing 11, and a rear upper portion of the main body housing 11. The support part 13 and the operation part 20 protruding from the front upper part of the right support part 12 are included.

  In the main body housing 11, various components of the image forming apparatus 1 are housed in addition to the image forming unit 30 (FIG. 3) that performs image forming processing on a sheet. A space on the upper surface of the main body housing 11 in an area where the right column portion 12 and the rear column portion 13 are not erected is used as a sheet discharge portion 14 for discharging a sheet after image formation.

  A sheet tray 141 that receives the sheet after image formation is formed on the upper surface of the main body housing 11, that is, on the bottom of the space of the paper discharge unit 14. The sheet tray 141 includes an inclined surface that gently falls from the left side surface 10L toward the inner vertical wall 121 of the right column 12. An expansion sheet tray 142 is attached to the space of the paper discharge unit 14 above the sheet tray 141. The right end portion of the additional sheet tray 142 is supported by a support portion provided on the inner standing wall 121, and the left end portion is supported by a support piece 143 erected from the vicinity of the left side surface 10L.

  The right column 12 is a housing that protrudes upward in the vicinity of the right side surface 10R on the upper surface of the main body housing 11, and has an inner vertical wall 121 (first vertical wall) adjacent to the paper discharge unit 14 (sheet tray 141). The inner standing wall 121 has a first sheet discharge port 122 (discharge port) and a second sheet discharge port 123 (discharge port) for discharging the image-formed sheet to the outside. In the vicinity of the sheet discharge ports 122 and 123, a discharge roller that applies a conveying force to the sheet is disposed. Sheets discharged from the first sheet discharge port 122 are stacked on the sheet tray 141, and sheets discharged from the second sheet discharge port 123 are stacked on the additional sheet tray 142.

  As illustrated in FIG. 4, in the image forming apparatus 1 of the present embodiment, instead of mounting the additional sheet tray 142, a usage mode in which the transport unit C is mounted immediately above the sheet tray 141 is used. be able to. A post-processing device (not shown) is optionally attached to the left side surface 10 </ b> L of the apparatus body 10. The post-processing device is a device that performs post-processing such as binding hole punching processing, stapling driving processing, and center folding processing on a sheet that has undergone image formation processing. The transport unit C is a unit that transports a sheet discharged from the first sheet discharge port 122 on the right side surface 10R side to a post-processing apparatus assembled on the left side surface 10L.

  The operation unit 20 includes a numeric keypad, a start key, and the like, and includes an operation panel 20P that receives input of various operation instructions from the user. The user can input the number of sheets to be printed, the print density, and the like through the operation panel 20P. The operation panel 20P is accommodated in the operation unit housing 21 (second housing). The operation portion housing 21 is a small housing provided so as to protrude further forward from the upper portion of the front wall 12W (second standing wall) of the right column portion 12 along the front surface 10F of the main body housing 11. In the vicinity of the upper surface of the operation unit housing 21, the operation panel 20P is accommodated in the operation unit housing 21, and an intake port 22 is provided on the lower surface of the operation unit housing 21 (see FIG. 2). The operation unit 20 will be described in detail later.

  Next, the internal structure of the image forming apparatus 1 will be described with reference to FIG. FIG. 3 is a cross-sectional view schematically showing the internal structure of the image forming apparatus 1. In the apparatus main body 10, an image forming unit 30 that performs image forming processing on a sheet, a sheet feeding unit 40 that stores a sheet conveyed to the image forming unit 30, and a sheet from the sheet feeding unit 40 to the image forming unit 30. And a conveyance path 50 that conveys the sheet to the sheet discharge ports 122 and 123 via the.

  The image forming unit 30 includes an image forming unit 31 that generates a toner image and transfers the toner image onto a sheet, and a fixing unit 36 that fixes the toner image on the sheet. The image forming unit 31 includes four units 32Y, 32M, and 32C that form yellow (Y), magenta (M), cyan (C), and black (Bk) toner images in order to form a full-color toner image. , 32Bk, an intermediate transfer unit 33 disposed adjacent to the image forming unit 32, and a toner replenishing unit 34 disposed on the intermediate transfer unit 33.

  Each of the image forming units 32Y, 32M, 32C, and 32Bk includes a photosensitive drum 321 and a charger 322, an exposure device 323, a developing device 324, a primary transfer roller 325, and a cleaning device disposed around the photosensitive drum 321. 326.

  The photosensitive drum 321 rotates about its axis, and an electrostatic latent image and a toner image are formed on its peripheral surface. As the photosensitive drum 321, a photosensitive drum using an amorphous silicon (a-Si) material can be used. The charger 322 uniformly charges the surface of the photosensitive drum 321. The exposure device 323 includes a laser light source and optical system devices such as a mirror and a lens, and forms an electrostatic latent image by irradiating the peripheral surface of the photosensitive drum 321 with light based on image data of a document image. .

  The developing device 324 supplies toner to the peripheral surface of the photosensitive drum 321 in order to develop the electrostatic latent image formed on the photosensitive drum 321. The developing device 324 is for a two-component developer and includes a stirring roller, a magnetic roller, and a developing roller. The stirring roller charges the toner by circulating and conveying the two-component developer while stirring. A two-component developer layer is carried on the circumferential surface of the magnetic roller, and a toner layer formed by the transfer of toner by a potential difference between the magnetic roller and the developing roller is carried on the circumferential surface of the developing roller. The The toner on the developing roller is supplied to the peripheral surface of the photosensitive drum 321 and the electrostatic latent image is developed.

  The primary transfer roller 325 forms a nip portion with the photosensitive drum 321 across the intermediate transfer belt 331 provided in the intermediate transfer unit 33, and the toner image on the photosensitive drum 321 is primary transferred onto the intermediate transfer belt 331. To do. The cleaning device 326 includes a cleaning roller and the like, and cleans the peripheral surface of the photosensitive drum 321 after the toner image is transferred.

  The intermediate transfer unit 33 includes an intermediate transfer belt 331, a driving roller 332, a driven roller 333, and a tension roller 334. The intermediate transfer belt 331 is an endless belt stretched around these rollers 332, 333, and 334, and toner images from a plurality of photosensitive drums 321 are overcoated on the outer peripheral surface of the intermediate transfer belt 331 ( Primary transfer). The driving roller 332 is a roller to which a driving force for rotating the intermediate transfer belt 331 is applied, and a secondary transfer roller 35 is disposed to face the peripheral surface. A nip portion between the driving roller 332 and the secondary transfer roller 35 becomes a secondary transfer portion 35A that transfers a full-color toner image overcoated on the intermediate transfer belt 331 to a sheet. The driven roller 333 is a roller that is driven according to the rotation of the intermediate transfer belt 331, and the tension roller 334 is a roller that applies a predetermined tension to the intermediate transfer belt 331.

  The toner supply unit 34 includes a yellow toner container 34Y, a magenta toner container 34M, a cyan toner container 34C, and a black toner container 34Bk. These toner containers 34Y, 34C, 34M, and 34Bk respectively store toner of each color, and are supplied to the developing devices 324 of the image forming units 32Y, 32M, 32C, and 32Bk corresponding to each color of YMCBk through a supply path (not shown). Supply toner of each color.

  The fixing unit 36 includes a fixing roller 361 provided on the outer periphery with a fixing belt heated by an induction heating method, and a pressure roller 362 that is pressed against the fixing roller 361 to form a fixing nip portion. The sheet on which the toner image has been secondarily transferred in the secondary transfer portion 35A passes through the fixing nip portion, and is subjected to fixing processing by being heated and pressed to fix the toner image on the sheet surface.

  The paper feed unit 40 includes two-stage paper feed cassettes 40A and 40B that accommodate sheets subjected to image forming processing. These paper feed cassettes 40A and 40B can be pulled forward from the front surface 10F of the apparatus main body 10. The paper feed cassettes 40A and 40B are cassettes provided for automatic paper feed. On the right side surface 10R of the apparatus main body 10, a paper feed tray 46 for manual paper feed is also provided. The paper feed tray 46 is attached to the apparatus main body 10 at its lower end so as to be openable and closable. When performing manual sheet feeding, the user opens the sheet feeding tray 46 as shown in FIGS. 2 and 4 and places a sheet thereon.

  The sheet feeding cassette 40A (40B) includes a sheet storage unit 41 that stores a sheet bundle formed by stacking a plurality of sheets, and a lift plate 42 that lifts up the sheet bundle for feeding. A pickup roller 43 and a roller pair of a paper feed roller 44 and a retard roller 45 are arranged on the upper right side of the paper feed cassette 40A (40B). By driving the pickup roller 43 and the paper feed roller 44, the uppermost sheet of the sheet bundle in the paper feed cassette 40A is fed out one by one and carried into the upstream end of the transport path 50. On the other hand, the sheet placed on the paper feed tray 46 is similarly carried into the conveyance path 50 by driving the pickup roller 461 and the paper feed roller 462.

  The conveyance path 50 includes a main conveyance path 50A that conveys a sheet from the paper feeding unit 40 to the exit of the fixing unit 36 via the image forming unit 31, and a sheet that is printed on one side when performing duplex printing on the sheet. A reverse conveyance path 50B for returning to the image forming unit 31 and a switchback conveyance path 50C for directing the sheet from the downstream end of the main conveyance path 50A to the upstream end of the reverse conveyance path 50B are included.

  A registration roller pair 51 is disposed on the upstream side of the main transfer path 50A from the secondary transfer portion 35A. The sheet is temporarily stopped by the registration roller pair 51, and after skew correction is performed, the sheet is sent to the secondary transfer unit 35A at a predetermined timing for image transfer. In addition, a plurality of conveyance rollers 52 for conveying the sheet are arranged in the main conveyance path 50A. The same applies to the other transport paths 50B, 50C, and 50D. A branch guide 54 for switching the sheet transport direction is provided at a branch portion of the main transport path 50A, the reverse transport path 50B, and the switchback transport path 50C.

<First Embodiment of Operation Unit>
Next, the operation unit 20 according to the first embodiment will be described in detail. FIG. 4 is a cross-sectional perspective view of the image forming apparatus 1 in the vicinity of the operation unit 20. 5 and 6 are perspective views of the operation unit 20 alone according to the first embodiment, and are different views from each other. As illustrated in FIG. 4, the operation unit housing 21 is a housing that protrudes forward from the front wall 12 </ b> W of the right column 12 and has a substantially isosceles triangular shape in a cross-sectional view in the front-rear direction. An internal space 211 (second internal space) having a substantially triangular prism shape is provided inside the operation unit housing 21. The internal space 211 communicates with the internal space 101 (first internal space) in the main body housing 11 via a communication portion 212 provided on the inner upper portion of the front wall 12W of the right column portion 12. A duct 23 is disposed in the internal space 211.

  A cooling fan 60 is disposed in the internal space 101 provided on the back surface of the front wall 12W of the right column 12. The cooling fan 60 moves when an operating voltage is applied, and generates an air flow. Specifically, the cooling fan 60 sucks air through the air inlet 22 of the operation unit housing 21, takes the air into the internal space 101 through the internal space 211 and the communication unit 212, and from the front along the unit of the fixing unit 36. Creates an air flow that flows backwards. The air flow cools the fixing unit 36 and peripheral devices. In FIG. 6, the cooling fan 60 is drawn closer to the operation unit housing 21 than the actual arrangement position.

  The operation unit housing 21 includes an upper surface 201 that inclines forward and downward from the base end, and a lower surface 202 that inclines upward from the base end and conversely. The operation unit housing 21 is formed by assembling the upper housing piece 203 having the upper surface 201 and the lower housing piece 204 having the lower surface 202 in the vertical direction.

  The operation panel 20P (operation input unit) is disposed along the upper surface 201. The upper surface 201 is provided with a plurality of through holes, and the operation buttons 213 of the operation panel 20P protrude upward from these through holes. The operation button 213 is mounted on the electric circuit board 20B. The electric circuit board 20 </ b> B is a rectangular flat plate, and is assembled directly below the upper surface 201 and substantially parallel to the upper surface 201.

  The lower surface 202 is provided with an intake port 22 for taking air into the internal space 101 when the cooling fan 60 is operated. As shown in FIG. 5, the intake port 22 is a louver including a plurality of slits 22L1, 22L2, 22L3, and 22L4 extending in the left-right direction. As in the present embodiment, it is preferable to provide the air inlet 22 on the lower surface 202 of the operation unit housing 21 from the viewpoint of air intake advantageous for cooling and aesthetics.

  That is, in the present embodiment, the main body housing 11 has an inner vertical wall 121 in which a sheet discharge port 122 for discharging the sheet after image formation to the outside is formed, and a front wall 12W along the front surface 10F of the main body housing 11. The right column portion 12 and a sheet tray 141 that is adjacent to the inner vertical wall 121 and receives the sheet discharged from the sheet discharge port 122 are provided. The operation portion housing 21 protrudes from the front wall 12W. Since the sheet immediately after the fixing process is discharged to the sheet tray 141, warm air is likely to be generated around the sheet tray 141. Such warm air is not suitable for cooling in the main body housing 11. However, according to the present embodiment, the operation unit housing 21 is disposed at a position separated from the sheet tray. Therefore, relatively cool air that is advantageous for cooling can be taken in from the intake port 22 provided on the lower surface 202 of the operation unit housing 21.

  Further, in order to take in sufficient air into the main body housing 11, it is preferable that the opening area of the intake port 22 is large. This is because the cooling fan 60 sucks the air in the internal space 101 and the cooling efficiency is reduced when the intake port has a small opening area. However, when an air inlet having a large opening area is provided in the front wall 12W, for example, the user visually recognizes the air inlet, which is not preferable in terms of the aesthetics of the image forming apparatus 1. On the other hand, in this embodiment, since the air inlet 22 is provided on the lower surface 202 of the operation unit housing 21, the air inlet 22 is not exposed to the normal line of sight of the user, and the aesthetic appearance of the image forming apparatus 1 is impaired. There is no.

  The duct 23 is disposed in the internal space 211 so as to cover the air inlet 22, and a user touches the electric circuit board 20 </ b> B through the air inlet 22, or a fallen object from the electric circuit board 20 </ b> B passes through the air inlet 22. It is a member that secures an air passage 23H (a space covered with a duct; see FIG. 4) from the air inlet 22 toward the internal space 101 of the main body housing 11 while preventing it from going outside. FIG. 7 is a perspective view of the duct 23 of the first embodiment, and FIG. 8 is a top view of the duct 23. In these figures, the upper housing piece 203 has been removed.

  The duct 23 includes a top surface piece 231 that faces the upper surface 201 of the operation unit housing 21, a left side surface piece 232 and a right side surface piece 233 that support the left and right side portions of the top surface piece 231, and a rear end portion of the top surface piece 231. And a drooping piece 234 bent downward. The duct 23 is formed of a sheet metal member, is easy to process, and has sufficient rigidity and heat resistance. For example, even if the user tries to insert a rod-like body from the air inlet 22, the insertion is blocked by the duct 23. Further, even if the electric circuit board 20B is heated and the resin parts are melted, it can be received by the duct and the molten material can be prevented from falling from the air inlet 22.

  The top surface piece 231 is a rectangular (substantially square) flat plate member disposed substantially parallel to the lower surface 202 of the operation unit housing 21 and has a sufficient area to cover the opening of the intake port 22. The top surface piece 231 has a larger area than the electric circuit board 20B. The electric circuit board 20 </ b> B is arranged above the area defined by the four sides of the top surface piece 231, and the air inlet 22 exists below. As a result, the above-described prevention of the user's contact with the electric circuit board 20B and the prevention of falling objects from the electric circuit board 20B become more reliable.

  The left side piece 232 and the right side piece 233 are erected on the left and right edges of the top piece 231. Flange portions 232T and 233T are provided at the upper edges of the left side piece 232 and the right side piece 233. Each flange portion 232T is fixed to an attachment portion (not shown) provided on the back surface of the upper surface 201 of the operation portion housing 21. On the other hand, as shown in FIG. 7, the lower end portions of the left side piece 232 and the right side piece 233 are not in contact with the lower surface 202, and the opening 24 is formed. The opening 24 is an opening for communicating the air passage 23H and the internal space 211 of the operation unit housing 21. In the first embodiment, the opening 24 has a lower end of the left side piece 232 and the right side piece 233. It is formed by providing a gap with the lower surface 202 of the operation housing 21.

  A number of through holes 234H are formed in the hanging piece 234. The air passage 23H and the communication portion 212 are communicated with each other through the through hole 234H. The vicinity of the lower end of the hanging piece 234 is fixed to the lower housing piece 204 with a screw 234B.

  In the image forming apparatus 1 configured as described above, when the cooling fan 60 is activated, an air flow is generated in which air enters the main body housing 11 from the air inlet 22 on the lower surface 202 of the operation unit housing 21. The air taken in from the air inlet 22 enters the air passage 23 </ b> H covered with the duct 23, and further reaches the internal space 211 of the operation unit housing 21 from the opening 24 below the left and right side pieces 232 and 233 of the duct 23. The air is guided to the internal space 101 in the main body housing 11 through the communication portion 212. At this time, the air in the internal space 211 warmed by the heat generated by the electric circuit board 20 </ b> B is also sent to the internal space 101. A part of the air taken in from the intake port 22 directly flows into the communication part 212 through the through hole 234H of the hanging piece 234. Thereafter, as shown by an arrow F in FIG. 4, the air is sent rearward along the outer peripheral surface of the fixing unit 36 by the cooling fan 60. Thereafter, the air exchanged with the heat in the machine is exhausted to the main body housing 11 by an unillustrated exhaust fan.

  According to the present embodiment, the air inlet 22 is provided on the lower surface 202 of the operation unit housing 21, and air is guided into the internal space 101 via the air inlet 22 and the duct 23 when the cooling fan 60 is operated. For this reason, a sufficient distance can be provided between the cooling fan 60 and the air inlet 22 without forming an extra space in the main body housing 11, and a sufficient space is ensured between the two. be able to. Accordingly, a stable air flow can be generated by the operation of the cooling fan 60, and the internal space 101 in the main body housing 11 can be effectively cooled by taking in an intended amount of air.

<Second Embodiment of Operation Unit>
Next, the operation unit 20A according to the second embodiment will be described. FIG. 9 is a perspective view of the operation unit 20A of the second embodiment, and FIG. 10 is a perspective view of the duct 25 of the second embodiment. In FIG. 9, the cooling fan 60 is drawn closer to the operation unit housing 21 than the actual arrangement position.

  The form of the operation unit housing 21 is the same as that of the first embodiment. An operation panel 20 </ b> P is disposed on the upper surface 201 of the operation unit housing 21, and an intake port 22 is provided on the lower surface 202. Further, the point that the electric circuit board 20B is arranged along the back surface of the upper surface 201 of the operation unit housing 21 is the same as that in the first embodiment. However, the form of the duct 25 is different. The duct 25 is formed of a bent member of a flat plate member made of sheet metal, and includes a top surface piece 251 that faces the upper surface 201 of the operation unit housing 21, a left side surface piece 252 that supports the left and right side portions of the top surface piece 251 from below, and And a right side piece 253, and has an inverted U-shape.

  Unlike the first embodiment, the top surface piece 251 is located near the lower side of the electric circuit board 20B. The area of the top surface piece 251 is larger than that of the electric circuit board 20B and the air intake port 22, and the electric circuit board 20B and the air intake port 22 are respectively arranged above and below the area defined by the periphery of the top surface piece 251. Yes. The left side piece 252 and the right side piece 253 extend downward from the left and right edges of the top piece 251, and these lower edges extend to the lower surface 202 of the operation unit housing 21. The distance between the left side piece 252 and the right side piece 253 is longer than the left and right width of the intake port 22, and the duct 25 completely covers the upper side of the intake port 22. The air passage 25H, which is a space covered with the duct 25, communicates with the communication portion 212 and the internal space 101 shown in FIG. That is, the rear surface of the duct 25 opens toward the communication part 212.

  A plurality of through holes 254 (openings) arranged in a line in the front-rear direction are provided in the vicinity of the left and right edges of the top surface piece 251. The internal space 26 (second internal space) in a region not occupied by the duct 25 in the operation unit housing 21 and the air passage 25 </ b> H are communicated with each other through a through hole 254.

  In the second embodiment, when the cooling fan 60 is activated, an air flow is generated in which air enters the main body housing 11 from the air inlet 22 on the lower surface 202 of the operation unit housing 21. The air taken in from the intake port 22 enters the air passage 25 </ b> H covered with the duct 25, and is further guided from the rear surface opening of the duct 25 to the internal space 101 in the main body housing 11 through the communication portion 212. At this time, the air in the internal space 26 warmed by the heat generated by the electric circuit board 20 </ b> B also flows into the air passage 25 </ b> H through the through hole 254 and is sent to the internal space 101. The subsequent air flow is in the direction indicated by arrow F in FIG. Also according to the second embodiment, a stable air flow can be generated by the operation of the cooling fan 60, and an intended amount of air is taken in to effectively cool the internal space 101 in the main body housing 11. Can do.

  The preferred embodiment of the image forming apparatus 1 according to the present invention has been described above. However, the present invention is not limited to the configuration of the above embodiment, and for example, the following modified embodiment can be taken.

  (1) In the above embodiment, an example is shown in which the main body housing 11 includes the front of the right column portion 12 (projecting housing), and the operation portion housing 21 (small housing) is disposed on the front wall 12W. This is merely an example, and for example, an operation unit housing may be protruded from one side surface of a rectangular parallelepiped main body housing.

  (2) In the said embodiment, the top surface pieces 231 and 251 of the ducts 23 and 25 showed the example of the plane board. The top surface pieces 231 and 251 may have a mountain-shaped bent shape, a dome-shaped curved shape, or the like.

  (3) In the above embodiment, the example in which the areas of the top surface pieces 231 and 251 are set larger than the electric circuit board 20 </ b> B and the air inlet 22 is shown. Although these are preferable examples, if the user can substantially prevent contact with the electric circuit board 20B and prevent the occurrence of falling objects from the electric circuit board 20B, the areas of the top surface pieces 231 and 251 are as follows. It may be slightly smaller than the electric circuit board 20 </ b> B and the air inlet 22.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 10 Apparatus main body 11 Main body housing 101 Internal space (1st internal space)
12 Right strut (protruding housing)
12W front wall (second standing wall)
121 Inside vertical wall (first vertical wall)
122 First sheet discharge port (discharge port)
123 Second sheet discharge port (discharge port)
14 Paper discharge unit 141 Sheet tray 20 Operation unit 20P Operation panel (operation input unit)
20B Electric circuit board 21 Operation part housing 211 Internal space (2nd internal space)
22 Inlet 23, 25 Duct 231, 251 Top piece 232, 233, 252, 253 Left side piece and right side piece 23H, 25H Air passage (space covered with duct)
24 opening 254 through hole (opening)
26 Internal space (second internal space)
30 Image forming unit 60 Cooling fan (cooling means)

Claims (3)

An image forming unit that performs image forming processing on the sheet;
A housing having a front surface, the first housing accommodating the image forming unit in a first internal space in the housing;
A small housing provided with an upper surface and a lower surface and projecting from the front surface of the main body housing, the small housing having a second internal space communicating with the first internal space;
A fan disposed in the first internal space and generating an air flow;
An intake port formed on the lower surface of the second housing for taking in air when the fan is operating;
A duct disposed in the second internal space so as to cover an upper portion of the intake port;
An opening that allows communication between the space covered with the duct and the second internal space;
With
The first housing is
A first standing wall extending in the front-rear direction and having a discharge port for discharging the image-formed sheet to the outside; a second standing wall extending in the left-right direction and extending along the front surface of the first housing; A protruding housing portion protruding into
A sheet tray adjacent to the first standing wall and receiving a sheet discharged from the discharge port,
The image forming apparatus, wherein the second housing is provided so as to protrude from the second standing wall and includes a left side surface portion extending forward along the first standing wall. The image forming apparatus according to claim 1.
The duct includes a top piece facing the top surface of the second housing, and a plurality of side pieces that support the top piece.
The opening is an image forming apparatus provided in the plurality of side surface pieces. The image forming apparatus according to claim 1.
The duct includes a top piece facing the top surface of the second housing, and a side piece supporting the top piece.
The image forming apparatus, wherein the opening is a hole formed in the top surface piece.

Images