JP2017207592A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus that can prevent a substance generated during fixing of a toner image from being discharged to the outside without sacrificing convenience for a user.SOLUTION: An image forming apparatus comprises: a paper ejection tray 60 that is provided on a bottom face of a space 6 between an image forming part 5 and an image reading part 3 in a body part 2; and an operation part 7. The space 6 has an opening surface 61 on the operation part side opening in a surface of the body part 2 on which the operation part 7 is provided, and includes a blow-off port 91 that blows off the air creating a layer of air for shielding the opening surface 61 on the operation part side; the blow-off port 91 blows off the air to the outside of an area of the paper ejection tray 60 where the maximum amount of recording sheet is loaded.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an image forming apparatus such as a copying machine or a printer.

  An image forming apparatus such as a copying machine, a printer, or a multifunction peripheral (MFP) thereof heats and presses a recording sheet on which a toner image has been transferred by a fixing device, thereby thermally fixing the toner image to the recording sheet. The recording paper on which the toner is fixed is stacked on a paper discharge tray outside the apparatus.

  In an image forming apparatus, when a toner image is fixed on a recording paper by a fixing device, fine particles, odors, and the like are generated from the recording paper, toner, materials used in the fixing device, and the like. Fine particles, odors, and the like are discharged from the discharge tray to the outside by being placed on the air flow such as convection generated by heat in the machine and laminar flow generated by discharging the paper.

  In order to reduce the size and / or improve the operability of the image forming apparatus, an operation unit for operating the image forming apparatus is provided in the vicinity of the paper discharge tray, and the user who operates the operation unit has been described above. Such fine particles and / or odors may be aspirated and uncomfortable.

  In view of this, for example, Patent Document 1 and Patent Document 2 disclose an image forming apparatus having a structure that suppresses the user from sucking fine particles and / or odors from around the discharge tray. In the image forming apparatus disclosed in Patent Document 1, substances generated when toner is fixed to a sheet are removed by sucking the air of at least one of the recording medium discharge unit and the recording medium placement unit. In addition, the image forming apparatus disclosed in Patent Document 2 includes a cover member that covers the space around the sheet on the placing unit and that can be opened and closed, and generates an air flow inside the cover member to generate a VOC generated inside the apparatus. The VOC gas generated from the gas or sheet is removed.

JP 2007-147834 A JP 2007-264077 A

  However, in the image forming apparatus of Patent Document 1, only the air around the recording medium discharge unit or the recording medium mounting unit is sucked, and the suction of the substance generated when fixing the toner on the paper is insufficient. Such substances are likely to leak to the outside.

  In addition, since the image forming apparatus of Patent Document 2 is covered with a cover member, the effect of preventing the VOC gas from leaking to the outside is high. However, it is necessary to open and close the cover member every time a printed sheet is taken out. The convenience of is not good.

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus that can suppress the release of a substance generated during fixing of a toner image to the outside without sacrificing user convenience.

  In order to achieve the above object, an image forming apparatus according to the present invention includes an image forming unit disposed at an intermediate portion in a vertical direction of a main body, an image reading unit disposed at an upper portion of the main body, and the image forming unit. A discharge tray provided on a bottom surface of a space between the image reading unit and the image forming unit on which a recording sheet is placed, and an operation unit that receives an operation input. The space has an opening surface on the operation portion side that is opened at least on a surface of the main body portion on which the operation portion is provided, and air that generates a layer of air that shields the opening surface on the operation portion side. A blowout opening is provided, and the blowout opening blows air toward an outside of a region where the largest recording sheet of the paper discharge tray is stacked.

  In the above-described image forming apparatus, the air outlet may be provided so as to flow an airflow in the vertical direction.

  In the above-described image forming apparatus, the space includes a paper discharge unit that is provided on one of the left and right surfaces adjacent to the opening surface on the operation unit side of the space and discharges the recording paper. The air outlet may have a larger opening area as it is closer to the paper discharge unit.

  In the above-described image forming apparatus, the air outlet may be a long hole extending along the opening surface on the operation unit side.

  In the above-described image forming apparatus, the space has an opening surface on the non-operation portion side on a surface different from a surface on which the operation portion of the main body portion is provided, and the blowout port is provided with the non-operation portion. You may provide in the position which produces the airflow which shields the opening surface of the side.

  In the above-described image forming apparatus, the image forming apparatus includes a suction portion that is provided to face the blower outlet and sucks the blown air, and a duct portion that communicates with the suction portion and through which the air sucked from the suction portion flows. The duct part may be arranged inside the main body part.

  In the above-described image forming apparatus, the opening area of the suction portion may be larger than the opening area of the air outlet.

  In the above-described image forming apparatus, the suction portion includes a first surface disposed on the paper discharge tray side and a second surface facing the first surface with a gap therebetween, and the first surface. The surface is provided with an inclined surface having an inclination in which the downstream side in the air flow direction approaches the second surface side, and the second surface has an opposing inclined surface disposed to face the inclined surface. It may be provided.

  In the above-described image forming apparatus, a part of the duct part may be included in an openable / closable cover provided in the main body part.

  In the above-described image forming apparatus, a blower that generates an airflow sucked from the suction portion may be provided inside the duct portion.

  In the above-described image forming apparatus, the duct portion is, when seen in a plan view, outside the region where the largest recording sheet of the discharge tray is stacked and below the region opposite to the discharge portion of the space. It extends to the side opposite to the operation part, and the blower may be provided close to the side of the duct part opposite to the operation part.

  In the above-described image forming apparatus, the flow rate of air sucked from the suction portion may be larger than the flow rate of air blown from the air outlet.

  In the image forming apparatus described above, a filter may be provided inside the duct portion.

  In the above-described image forming apparatus, the duct part may have a circulation path for returning the air sucked from the suction part to the outlet.

  In the above-described image forming apparatus, the air outlet is provided on the upper surface of the space, the suction portion is provided on the lower surface of the space, and the upper end portion of the inclined surface is lower than the lower end portion of the paper discharge tray. The upper end of the opposite inclined surface may be above the upper end of the slope.

  In the above-described image forming apparatus, at least one suction pipe that communicates the upper surface of the paper discharge tray and the duct portion is provided, and the opening at the upper end of the suction pipe is the largest recording sheet of the paper discharge tray. The position may be lower than the surface on which the recording paper of the paper discharge tray is placed outside the area where the paper is stacked.

  In the image forming apparatus described above, the flow path cross-sectional area of the suction pipe may be narrower on the downstream side in the airflow direction than on the upstream side.

  In the above-described image forming apparatus, air may be blown out from the air outlet when the fixing temperature adjustment in the image forming unit is equal to or higher than a predetermined temperature.

  In the above-described image forming apparatus, when the fixing temperature control in the image forming unit is equal to or higher than a predetermined temperature, air may be blown from the blowout port and air may be sucked in from the suction unit.

  In the above-described image forming apparatus, the sum of the flow rate of air sucked from the suction portion and the flow rate of air blown from the blowout port may be larger when close to the paper discharge portion.

  According to the present invention, it is possible to provide an image forming apparatus capable of suppressing the release of a substance generated at the time of fixing a toner image without sacrificing user convenience.

1 is an external perspective view of an image forming apparatus of the present invention. 2 is a left side view of the image forming apparatus. FIG. 1 is a schematic diagram illustrating an internal configuration of an image forming apparatus of the present invention. 2 is a schematic perspective view illustrating a structure of a paper discharge tray of the image forming apparatus according to the present invention. FIG. FIG. 3 is a side view showing a schematic arrangement of a paper discharge tray of the image forming apparatus according to the present invention. FIG. 3 is a plan view showing a schematic arrangement of a paper discharge tray of the image forming apparatus according to the present invention. It is the enlarged view which looked at the blower outlet from diagonally downward. It is a figure which shows arrangement | positioning of a duct part.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following explanation, when using terms indicating a specific direction or position (for example, “left / right”, “up / down”, etc.) as necessary, the direction orthogonal to the paper surface in FIG. I have to. These terms are used for convenience of explanation, and do not limit the technical scope of the present invention.

<Overall configuration of image forming apparatus>
An overall configuration of an image forming apparatus common to the following embodiments will be described with reference to the drawings. FIG. 1 is an external perspective view of the image forming apparatus of the present invention, and FIG. 2 is a left side view of the image forming apparatus. FIG. 3 is a schematic diagram showing the internal configuration of the image forming apparatus of the present invention. As shown in FIGS. 1 and 2, the image forming apparatus 1 includes an image reading unit 3, a drawer device 4, an image forming unit 5, a paper discharge tray 60, and an operation panel 7.

  The image reading unit 3 reads an image from the document P1. The drawer device 4 stores recording paper P2 on which an image is formed. The image forming unit 5 forms an image on the recording paper P <b> 2 fed from the drawer device 4. The recording paper P2 on which the image is formed by the image forming unit 5 is discharged to the paper discharge tray 60. The operation panel 7 receives an operation on the image forming apparatus 1. In the image forming apparatus 1, an image reading unit 3 is provided on the upper part of the apparatus main body 2, and an image forming unit 5 is provided below the image reading unit 3. The apparatus main body 2 corresponds to a “main body” in the claims.

  A paper discharge tray 60 is provided on the upper side of the image forming unit 5 in the apparatus main body 2 in order to receive the recording paper P2 on which an image is recorded and discharged by the image forming unit 5. The drawer device 4 is configured to be insertable / removable on the lower side of the image forming unit 5 in the apparatus main body 2. By having the above configuration, as will be described later, the image forming apparatus 1 forms (prints) an image on the recording paper P2. That is, the recording paper P <b> 2 stored in the drawer device 4 is fed into the apparatus main body 2, is then transported upward, and is supplied to the image forming unit 5 disposed on the top of the drawer device 4. Then, after the image is formed by the image forming unit 5, the recording paper P <b> 2 is discharged to a discharge tray 60 provided in a space 6 (a recessed space) between the image reading unit 3 and the image forming unit 5. . Hereinafter, each part of the image forming apparatus 1 will be described in detail.

  The operation panel 7 is provided on the front side (front side) of the apparatus body 2. The user operates the keys while viewing the display screen of the operation panel 7 to perform setting operations for the functions selected from the various functions of the image forming apparatus 1 or instruct the image forming apparatus 1 to perform work. I can do it.

  The image reading unit 3 is provided on the upper part of the apparatus main body 2 and reads an image from the document P1. The image reading unit 3 includes a scanner unit 31 and an automatic document feeder (ADF) 32. The scanner unit 31 reads an image from the document P1. The automatic document conveying unit 32 is provided on the upper portion of the scanner unit 31 and conveys the document P1 to the scanner unit 31 one by one.

  As shown in FIG. 3, the scanner unit 31 of the image reading unit 3 includes a document table 33, a light source device 34, an image sensor 35, an imaging lens 36, and a mirror group 37. The document table 33 has a platen glass (not shown) on the upper surface side. The light source device 34 irradiates the document P1 with light. The image sensor 35 photoelectrically converts the reflected light from the document P1 into image data. The imaging lens 36 is a lens that images the reflected light on the image sensor 35. The mirror group 37 sequentially reflects the reflected light from the document P1 and enters the imaging lens 36, and includes a plurality of mirrors. The light source device 34, the image sensor 35, the imaging lens 36, and the mirror group 37 are provided inside the document table 33, and the light source device 34 and the mirror group 37 are configured to be movable in the left-right direction with respect to the document table 33. .

  An ADF 32 is provided on the upper surface side of the scanner unit 31 so as to be openable and closable with respect to the document table 33. The ADF 32 also has a function of bringing the document P1 into close contact with the platen glass (not shown) by covering the document P1 on the platen glass (not shown) of the document table 33. The ADF 32 includes a document placement tray 38 and a document discharge tray 39.

  When the image reading unit 3 reads a document P1 on a platen glass (not shown) of the document table 33, light is emitted to the document P1 from the light source device 34 that moves in the right direction (sub-scanning direction). The reflected light reflected by the document P1 is sequentially reflected by the mirror group 37 that moves in the right direction as in the light source device 34, enters the imaging lens 36, and forms an image on the image sensor 35. The image sensor 35 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 P1.

  On the other hand, when reading the document P1 placed on the document placement tray 38, the document P1 is transported to the reading position by the document transport mechanism 40 including a plurality of rollers and the like. At this time, the light source device 34 and the mirror group 37 of the scanner unit 31 are fixed at predetermined positions inside the document table 33. Accordingly, the light source device 34 irradiates the reading position portion of the document P1 with light, and the reflected light forms an image on the image sensor 35 via the mirror group 37 and the imaging lens 36 of the scanner unit 31. The image sensor 35 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 P1. Thereafter, the document P1 is discharged to the document discharge tray 39.

  The drawer device 4 stores recording paper P <b> 2 on which an image is formed, and is provided at the lower portion of the apparatus body 2. The drawer device 4 includes a paper feed cassette 41 and a cassette storage unit 42. The paper feed cassette 41 is inserted and removed by sliding in the front-rear direction with respect to the cassette housing portion 42 of the apparatus main body 2. The paper feed cassette 41 includes a front cover 411 and a recording paper storage unit 412. The front cover 411 is a plate-like member that constitutes a part of the front surface of the apparatus main body 2.

  The recording paper storage unit 412 has a casing shape in which the front, rear, left and right of the bottom plate 413 on which the recording paper P2 is placed are surrounded by side plates. On the right side of the bottom plate 413, a push-up plate 414 that pushes the recording paper P <b> 2 upward by rotating the right edge up and down is provided on the upper surface of the bottom plate 413. In addition, a recording paper regulating portion 415 protruding from the bottom plate 413 is configured to be slidable to the left and right at the left portion of the bottom plate 413. Then, the position of the left side edge of the recording paper P2 is regulated by the recording paper regulating unit 415 so that the right side edge of the recording paper P2 comes into contact with the right inner wall. The bottom plate 413 is provided with a paper width regulating plate (not shown) for regulating the paper width of the recording paper P2 placed on the push-up plate 414 so as to protrude from the bottom plate 413 and slide back and forth.

  When the paper feed cassette 41 is inserted into the cassette storage section 42, the recording paper storage section 412 is stored inside the apparatus main body 2 and the front cover 411 covers the front surface of the apparatus main body 2. A paper feed mechanism 8 (see FIG. 3), which will be described later, is disposed on the right side of the recording paper storage unit 412 stored in the cassette storage unit 42. The recording paper P <b> 2 is pulled out from the recording paper storage unit 412 by the paper supply mechanism 8 and conveyed to the image forming unit 5.

  The sheet feeding mechanism 8 includes a feeding roller 81, a sheet feeding roller 82, and a separating roller 83. The feeding roller 81 feeds the recording paper P2 stored in the recording paper storage unit 412 from the uppermost layer. The paper feed roller 82 and the separating roller 83 are a pair of separation rollers that separate the recording paper P2 fed by the feed roller 81 one by one. The recording paper P2 in the recording paper storage unit 412 of each drawer device 4 passes through the paper feed path R1 one by one from the top layer by the rotational drive of the corresponding feed roller 81, paper feed roller 82 and paper roller 83. Is sent out toward the main transport path R0. The main transport path R0 is the main path of the recording paper P2 that has undergone the image forming (printing) process. In addition, a paper feed path R1 is provided for each drawing device 4, and each paper feed path R1 joins the main transport path R0.

  A manual feed tray 86 capable of feeding a predetermined size of recording paper P2 from the outside is provided on one side of the apparatus body 2 in the left-right direction (right side in the embodiment). The manual feed tray 86 is provided in an auxiliary manner separately from the normal drawer device 4 in the apparatus main body 2, and is attached to the left and right sides of the apparatus main body 2 so as to be openable and closable. Yes. The recording paper P2 on the manual feed tray 86 is fed one by one from the uppermost layer toward the main transport path R0 via the manual feed path R2 by rotation driving of a feed roller or the like.

  An image is formed (printed) by the image forming unit 5 on the recording paper P2 sent to the main transport path R0. The image forming unit 5 includes a transfer unit that transfers the toner image onto the recording paper P2, and a fixing unit that fixes the toner image onto the recording paper P2. The transfer unit of the image forming unit 5 includes an image forming unit 51, an exposure unit 52, an intermediate transfer belt 53, a primary transfer roller 54, a driving roller 55, a driven roller 56, a secondary transfer roller 57, and a cleaner. Part 58. As shown in FIG. 3, the image forming unit 51 generates toner images of each color of Y (Yellow), M (Magenta), C (Cyan), and K (Key tone). The image forming unit 51 that generates toner images of Y, M, C, and K colors has the same configuration except that the toner used is different. Therefore, in FIG. 3, only the components of the Y image forming unit 51 are denoted by reference numerals, and in the following description, the Y image forming unit 51 will be described, but the same applies to the M, C, and K image forming units 51. It is a configuration.

  The image forming unit 51 includes a photosensitive drum 511, a charger 512, a developing unit 513, and a cleaner unit 514. The photosensitive drum 511 is in contact with the outer peripheral surface of the intermediate transfer belt 53. The charger 62 charges the outer peripheral surface of the photosensitive drum 511 by corona discharge. In the present embodiment, a non-contact type charging by corona discharge is used, but the present invention is not limited to this, and a contact type charging by contacting a roller or a brush may be used. The developing device 513 causes the toner charged by stirring to adhere to the outer peripheral surface of the photosensitive drum 511. The cleaner unit 514 removes the toner remaining on the outer peripheral surface of the photosensitive drum 511 after the toner image is transferred to the intermediate transfer belt 53.

  The photosensitive drum 511 is installed at a position facing the primary transfer roller 54 with the intermediate transfer belt 53 interposed therebetween, and rotates in the clockwise direction in FIG. Around the photosensitive drum 511, a primary transfer roller 54, a cleaner unit 514, a charger 512, an exposure unit 52, and a developing unit 513 are sequentially arranged along the rotation direction of the photosensitive drum 511. .

  The exposure unit 52 is provided below the image forming unit 51 of each color. For example, the exposure unit 52 irradiates the photosensitive drum 511 with a laser beam or the like to create an electrostatic latent image on the photosensitive drum 511.

  The intermediate transfer belt 53 is in contact with the image forming units 51 of the respective colors arranged in the horizontal direction, and the toner images of the respective colors generated by the image forming unit 51 are transferred. The intermediate transfer belt 53 is composed of an endless belt member having conductivity, for example. The primary transfer roller 54 is provided at a position facing the image forming unit 51 of each color on the upper side so as to sandwich the image forming unit 51 and the intermediate transfer belt 53.

  The intermediate transfer belt 53 is wound around the driving roller 55 and the driven roller 56 without being loosened. In this state, the intermediate transfer belt 53 is rotated by rotating the drive roller 55 with a drive device such as a motor (not shown). The rotation direction is a counterclockwise direction in FIG. When the rotation of the driving roller 55 is transmitted to the intermediate transfer belt 53, the primary transfer roller 54 and the driven roller 56 that are in contact with the intermediate transfer belt 53 also rotate. Around the intermediate transfer belt 53, a secondary transfer roller 57, a cleaner unit 58, and an image forming unit 51 for each color of YMCK are arranged in order along the rotation direction of the intermediate transfer belt 53.

  The secondary transfer roller 57 is disposed at a position facing the drive roller 55 with the intermediate transfer belt 53 interposed therebetween. The cleaner unit 58 is installed at a position facing the driven roller 56 with the intermediate transfer belt 53 interposed therebetween.

  The image forming unit 5 includes a heating roller 59 and a pressure roller 50 as a fixing unit. The heating roller 59 includes a halogen lamp that heats the toner image on the recording paper P2 to be fixed. The pressure roller 50 sandwiches the recording paper P2 together with the heating roller 59 and pressurizes the recording paper P2. The heating roller 59 may be one in which the surface of the heating roller 59 is heated by generating an eddy current on the surface by electromagnetic induction.

  A discharge roller pair 84 for discharging the printed recording paper P <b> 2 is disposed on the downstream side of the main conveyance path R <b> 0 with respect to the fixing unit formed by the heating roller 59 and the pressure roller 50. The printed recording paper P2 is discharged to the paper discharge tray 60 by the rotational driving of the paper discharge roller pair 84.

  Further, in the apparatus main body 2 of the image forming apparatus 1 configured as described above, there is further provided a circulation conveyance unit 85 for performing double-sided printing by reversing the recording paper P2 after single-sided printing. . The circulation conveyance unit 85 includes a pair of reversing rollers for reversing the recording paper P2 after single-sided printing, and a plurality of pairs of double-sided conveyance rollers. In the circulation conveyance unit 85, the recording paper P2 after single-sided printing is turned upside down and conveyed again to the main conveyance path R0 via the circulation conveyance path R3. In this case, the discharge roller pair 84 is configured to be capable of forward and reverse rotation, so that the discharge roller pair 84 also functions as a reverse roller pair. The recording paper P2 can be discharged out of the image forming apparatus 1 by the forward and reverse rotation of the paper discharge roller pair 84, or returned to the image forming apparatus 1 by switching back (reversely feeding). The upstream side of the circulation conveyance path R3 branches off from between the fixing unit of the image forming unit 5 and the paper discharge roller pair 84 in the main conveyance path R0. The downstream side of the circulation conveyance path R3 joins the upstream side of the transfer unit of the image forming unit 5.

  A printing operation by the image forming apparatus 1 will be briefly described. The image forming apparatus 1 receives a start signal, an image signal, and the like and starts a printing operation. When the printing operation is started, the recording paper P2 fed from the drawer device 4 by the paper feed mechanism 8 is conveyed to the image forming unit 5 along the main conveyance path R0. The image forming unit 5 transfers and fixes an image on the recording paper P2 based on a color electrophotographic method, and adopts an intermediate transfer method using an intermediate belt 53 as an image transfer method to the recording paper P2.

  In the transfer unit of the image forming unit 5, the Y, M, C, and K color image forming unit 51 irradiates the surface of the photosensitive drum 511 charged by the charger 512 with laser light from the exposure unit 52. , M, C, and K, electrostatic latent images corresponding to the respective color images are formed. The toner charged by the developing device 513 is transferred to the surface of the photosensitive drum 511 on which the electrostatic latent image is formed, and a toner image is formed on the surface of the photosensitive drum 511. The toner image carried on the surface of the photosensitive drum 511 is transferred to the intermediate transfer belt 53 by the electrostatic force of the primary transfer roller 54 when contacting the intermediate transfer belt 53. On the surface of the intermediate transfer belt 53, a toner image in which the colors Y, M, C, and K are overlapped is formed. On the other hand, the untransferred toner remaining on the photosensitive drum 511 having the toner image transferred to the intermediate transfer belt 53 is scraped off by the cleaner unit 514 and removed from the photosensitive drum 511.

  The toner image transferred to the intermediate transfer belt 53 is moved to the transfer position where the intermediate transfer belt 53 contacts the secondary transfer roller 57 by the rotation of the intermediate transfer belt 53 by the driving roller 55 and the driven roller 56, and on the main transport path R0. It is transferred to the recording paper P2 conveyed to the transfer position. Untransferred toner remaining on the intermediate transfer belt 53 that has transferred the toner image onto the recording paper P <b> 2 is scraped off by the cleaner unit 58 and removed from the intermediate transfer belt 53. Further, the recording paper P <b> 2 on which the toner image is transferred at the contact position with the secondary transfer roller 57 is conveyed to a fixing unit by the heating roller 59 and the pressure roller 50.

  The recording paper P2 on which the unfixed toner image is placed on one side is heated by the heating roller 59 and pressed by the pressure roller 50 when passing through the fixing position of the fixing unit, so that the unfixed toner image is applied to the paper surface. It is fixed. In the case of single-sided printing, the recording paper P <b> 2 after toner image fixing (after single-sided printing) is discharged to the paper discharge tray 60 by the paper discharge roller pair 84. On the other hand, in the case of double-sided printing, the recording paper P2 after single-sided printing is conveyed to the circulation conveyance path R3 for double-sided printing, turned over, and returned again to the main conveyance path R0, so that the image forming unit 5 re-records the recording paper P2. After the toner image is transferred and fixed on the other surface, the toner image is discharged to the paper discharge tray 60.

  With reference to the drawings, a description will be given of a paper discharge tray, which is a main part of the image forming apparatus according to the present invention, and its periphery. FIG. 4 is a schematic perspective view showing the structure of the paper discharge tray of the image forming apparatus according to the present invention. FIG. 5 is a side view showing a schematic arrangement of the paper discharge tray of the image forming apparatus according to the present invention. FIG. 6 is a plan view showing a schematic arrangement of the paper discharge tray of the image forming apparatus according to the present invention. FIG. 7 is an enlarged view of the air outlet as seen obliquely from below. FIG. 8 is a diagram showing the arrangement of the duct portion.

  As shown in FIGS. 4 to 8, the space 6 between the image forming unit 5 and the image reading unit 3 is an opening on the operation unit side that is open on the surface (front surface) where the operation unit 7 of the apparatus body 2 is provided. 61 and an opening surface 62 on the non-operation portion side that opens to a surface (left surface) where the operation portion 7 is not provided. A paper discharge tray 60 is provided on the bottom surface of the space 6. Then, in order to prevent fine particles, odorous components, and the like discharged into the space 6 from being sprayed by a user outside the apparatus main body 2, the opening surface 61 on the operation unit side and the opening surface 62 on the non-operation unit side are aired. An air curtain generator 9 is provided for shielding with a layer.

  The air curtain generating device 9 includes an air outlet 91, a suction portion 92, a duct portion 93, a suction side blower 94, a filter 95, a blowout side blower 96, and a suction pipe 97. The duct portion 93 is formed inside the apparatus main body 2.

  As shown in FIGS. 5 and 8, the duct portion 93 includes an upstream duct 931, a downstream duct 932, and a connecting duct 933. The upstream duct 931 is provided in the upper part 21 (hereinafter simply referred to as the upper part 21) of the space 6 of the apparatus main body 2 in which the image reading unit 3 is provided. The upstream duct 931 includes a first portion 9311 extending forward from the rear right side of the apparatus main body 2, a second portion 9312 extending leftward from the front end of the first portion 9311, and a third portion extending rearward from the left end of the second portion. Part 9313.

  The downstream duct 932 is provided inside the lower part 22 (hereinafter simply referred to as the lower part 22) of the space 6 of the apparatus main body 2. The downstream duct 932 includes a first portion 9321 provided on the front side of the lower portion 22 and extending from right to left, and a second portion 9322 extending rearward at the left end of the first portion 9321 and extending rearward. . The second portion 9312 of the upstream duct 931, the first portion 9321 of the downstream duct 932, the third portion 9313 of the upstream duct 931, and the second portion 9322 of the downstream duct 932 are vertically opposed. The connecting duct 933 is provided inside the wall portion 23 on the rear side of the space 6 of the apparatus main body 2. The connection duct 933 connects the downstream duct 932 and the upstream duct 931.

  The blower outlet 91 opens downward on the lower surface of the upper portion 21. The air outlet 91 communicates with the upstream duct 931 and blows air that has flowed through the upstream duct 931 toward the bottom surface of the space 6. The shape of the air outlet 91 is discharged to the paper discharge tray 60 and is directed toward the outside of the area Ar1 (see FIG. 6) on which the largest recording paper among the recording papers to be placed is placed. The air can be blown out.

  As shown in FIGS. 7 and 8, the air outlet 91 is a long hole (911) provided on the front side of the lower surface of the upper portion 21 and extending in the left and right direction and a long hole (912) provided on the left side of the lower surface in the front and rear direction. is there. An air layer (air curtain) that shields the opening surface 61 on the operation unit side of the space 6 is generated by the air blown out from the air outlet 911 provided on the front side of the lower surface of the upper portion 21. In addition, an air layer (air curtain) that shields the opening surface 62 on the non-operation part side of the space 6 is generated by the air blown from the air outlet 912 provided on the left side of the lower surface of the upper portion 21. In the following description, what is provided on the front side of the lower surface of the upper portion 21 with respect to the air outlet 91 is referred to as an air outlet 911, and what is provided on the left side of the lower surface of the upper portion 21 is referred to as an air outlet 912. There is a case. In addition, in this embodiment, although the blower outlet 91 (911, 912) is made into the long hole, it is not limited to this. For example, a configuration in which a plurality of circular or polygonal holes are arranged may be used. As the shape of the air outlet 91, it is possible to widely adopt a shape capable of generating an air curtain that can shield the opening surfaces 61 and 62 evenly.

  As shown in FIG. 7, the air outlet 911 provided on the front side of the lower surface of the upper portion 21 is narrowed from the right side to the left side. Thereby, the layer of air that shields the opening surface 61 on the operation unit side is thicker on the right side than on the left side. This is for the following reason. A discharge unit 63 for discharging the recording paper P <b> 2 is provided on the right side surface of the space 6, and particulates, odor components and the like are also discharged from the discharge unit 63. That is, since the concentration of fine particles, odor components, etc. is high in the vicinity of the discharge portion 63, the effect of suppressing the spray of fine particles, odor components, etc. to the user by thickening the air layer in the vicinity of the discharge portion 63. It is increasing.

  As shown in FIGS. 4 and 5, the suction portion 92 is provided on the front side of the apparatus main body 2. The suction part 92 sucks the air blown out from the blowing part 911 provided on the front side of the upper lower surface. The suction portion 92 has an opening 920 that opens upward, a first surface 921 on the discharge tray 60 side, and a second surface 922 that is provided in front of the first surface 921 with a gap. The suction portion 92 communicates with the downstream duct 932. The opening 920 is provided to extend left and right on the front side of the bottom surface of the space 6. On the first surface 921, an inclined surface 923 having an inclination in which the lower side approaches the second surface 922 is provided below the opening 920. Further, the second surface 922 is provided with an opposing inclined surface 924 that opposes the front and back of the inclined surface 923 and vertically. In addition, the area of the opening part 920 of the suction part 92 is formed larger than the area of the blower outlet 911. Thereby, the flow volume of the air which flows through the suction part 92 becomes larger than the flow volume of the air which flows through the blower outlet 911. Therefore, it suppresses that the air which generates an air curtain blows on the user side. This suppresses spraying fine particles, odor components, etc. on the user.

  In the suction portion 92, the air sucked from the opening portion 920 passes through the gap sandwiched between the first surface 921 and the second surface 922 and flows into the downstream duct 932. Further, since the inclined surface 923 is provided on the first surface 921, even if the flow of the air flowing into the suction portion 92 is reflected by the inclined surface 923, the recording paper P2 placed on the paper discharge tray 60 can be used. Suppressing being sprayed. Further, since the opposed inclined surface 924 is provided, the air flow reflected by the inclined surface 923 is suppressed from being blown to the user. The inclined surface 923 preferably has the uppermost end of the inclined surface 923 below the lower end of the discharge tray 60 so that the air flow does not go to the discharge tray 60. In addition, the uppermost end of the opposed inclined surface 924 is preferably higher than the uppermost end of the inclined surface 923. Furthermore, the uppermost end of the opposing inclined surface 924 may be below the lower end of the discharge tray 60 so that the air flowing along the opposing inclined surface 924 does not go to the discharge tray 60. preferable.

  As shown in FIG. 5, in the apparatus main body 2, the first surface 921 is formed on the side surface of the main body, and the second surface 922 is formed on the inner surface of the front cover 24 that is rotatably provided. . Further, the front cover 24 is opened with the upper part pivoting forward with the lower end as an axis, and the lower end inside the front cover 24 is formed with a curved surface for smoothly bending the air flow of the suction portion 92. The louver 241 is provided. Therefore, the suction portion 92 and the downstream duct 932 can be accessed by opening the front cover 24. Therefore, convenience during maintenance is high.

  As shown in FIGS. 5 and 8, the suction side blower 94 is provided inside the duct portion 93, specifically, the most downstream side of the downstream side duct 932, that is, the left side of the rear portion of the lower portion 22. The suction-side blower 94 causes the downstream duct 932 to generate an air flow in which external air flows into the downstream duct 932 from the suction portion 92 and the suction pipe 97. The suction side blower 94 may be an axial fan or a centrifugal fan. In addition to these, those capable of generating an air flow can be widely employed.

  Air discharged from the suction side blower 94 flows into the connection duct 933. That is, the suction side blower 94 generates airflow in the downstream duct 932 and also generates airflow in the connection duct 933. Further, a filter 95 is provided at a position close to the suction side blower 94 in the duct portion. In the air curtain generator 9, the suction part 92 sucks air blown from the blower outlet 91, but also sucks part of the air inside the space 6. The air inside the space 6 contains fine particles, odor components, and the like discharged from the discharge unit 63, and the filter 95 collects these substances. Since fine particles, odor components, and the like generated in the image forming apparatus 1 are known in advance, a filter 95 corresponding to the substance is used. In order to prevent fine particles, odorous components, and the like from coming into contact with the suction-side fan 94, the filter 95 is preferably provided upstream of the suction-side fan 94 in the air flow direction.

  The blower-side blower 96 is disposed on the upstream end of the first portion 9311 of the upstream duct 931, that is, on the right side of the rear portion of the upper portion 21. The blower-side blower 96 causes the upstream duct 931 to generate an airflow in a direction in which air is blown from the blowout port 91. The blower side blower 96 may have the same configuration as the suction side blower 94 or may have a different configuration. In order to increase the amount of air sucked from the suction portion 92 and the suction pipe 97 with respect to the amount of air blown from the outlet 91, the discharge capacity of the suction side blower 94 is set larger than the discharge capacity of the blower side blower 96. May be.

  Nine suction pipes 97 are provided in the lower part 22. The suction pipe 97 is a pipe that communicates the bottom surface of the space 6 and the downstream duct 932. The suction pipe 97 has an upper end opening 971. As shown in FIGS. 4 and 5, the upper end opening 971 of the suction pipe 97 is arranged side by side on the front side and the left side of the bottom surface of the space 6. A suction pipe 97 having an upper end opening 971 at the front portion of the bottom surface of the space 6 communicates with the first portion 9321 of the downstream duct 932. The suction pipe 97 provided with an upper end opening 971 on the left side of the bottom surface of the space 6 communicates with the second portion 9322 of the downstream duct 932. The cross-sectional area of the suction pipe 97 that communicates with a portion of the downstream duct 932 that is remote from the suction-side fan 94 is larger than the cross-sectional area of the suction pipe 97 that communicates with a close portion. By setting it as such a structure, the difference of the flow volume of the air which flows through each of the suction pipe 97 is made small.

  Further, the upper end opening 971 is disposed outside the area Ar1 on which the maximum recording paper placed on the paper discharge tray 60 is placed. This makes it difficult for the suction pipe 97 to be blocked by the recording paper. Further, since the suction pipe 97 sucks the air in the space 6, it can be interpreted as a part of the suction portion 92. Therefore, the sum of the areas of the suction pipe 97 upper end opening 971 and the area of the opening 920 of the suction portion 92 may be formed to be larger than the sum of the areas of the air outlet 91.

  The operation of the air curtain generating device 9 configured as described above will be described. The flow of air in the duct during the operation of the air curtain generator 9 is indicated by arrows in FIGS. In the image forming apparatus 1, an air curtain that shields the opening surfaces 61 and 62 of the space 6 is generated in order to prevent fine particles, odor components, and the like discharged to the space 6 from being sprayed by a user operating the operation unit 7. To do. When the air curtain generator 9 is driven, the blower side blower 96 and the suction side blower 94 are driven. As a result, an air flow is generated in the upstream duct 931 and the downstream duct 932 of the duct portion 93.

  First, the airflow in the upstream duct 931 will be described. By driving the blow-out side blower 96, an air flow directed from the rear to the front is generated in the first portion 9311 of the upstream duct 931 which is the discharge side of the blow-out side blower 96. This airflow flows through the second portion 9312 from right to left, and further flows through the third portion 9313 from the front to the back. Part of the airflow flowing through the second portion 9312 is blown out from the blowout port 911 communicating with the second portion 9312 toward the suction portion 92 on the front side of the paper discharge tray 60. The air blown out from the outlet 911 serves as an air curtain that shields the opening surface 61 on the operation unit side of the space 6. Further, the airflow that has flowed through the third portion 9313 is blown out from the blowout port 912 communicating with the third portion 9313 toward the outside of the area Ar1 on which the maximum recording paper is placed on the left side of the paper discharge tray 60. . The air blown out from the air outlet 912 becomes an air curtain that shields the opening surface 62 on the non-operation part side of the space 6. At this time, an air flow from the downstream duct 932 toward the upstream duct 931 is also generated in the connection duct 933 provided on the suction side of the blower blower 96.

  The suction side blower 94 is also driven simultaneously or substantially simultaneously with the driving of the blowout side blower 96. At this time, in the second portion 9322 of the downstream duct 932, an airflow flowing into the suction side blower 94, that is, an airflow is generated from the front to the rear. Due to the generation of this airflow, an airflow flowing from the right to the left is also generated in the first portion 9321 communicating with the second portion 9322. By generating such an air flow, an air flow for sucking air in the space 6 is generated in the suction portion 92 and the suction pipe 97 communicating with the first portion 9321 and the suction tube 97 communicating with the second portion 9322. .

  That is, the air blown out from the air outlet 911 is sucked in from the suction portion 92 and the suction pipe 97 communicating with the first portion 9321, flows into the first portion 9321, and is generated in the first portion 9321. It flows into the second portion 9322 as an air flow. Further, the air blown out from the air outlet 912 is sucked in from the suction pipe 97 communicating with the second portion 9322 and flows into the second portion 9322. A filter 95 is provided in the second portion 9322. The suction portion 92 and the suction pipe 97 suck in the air blown out from the blowout ports 911 and 912, but also suck in air in the vicinity of the space 6. Thereby, the air in the space 6 containing fine particles, odor components, and the like discharged from the discharge unit 63 is also sucked. That is, the air flowing in the downstream duct 932 contains fine particles, odor components, and the like. Since the airflow generated in the downstream duct 932 is formed so as to pass through the filter 95, the fine particles, odor components, etc. contained in the sucked air are collected by the filter 95, and clean air is collected. Then, it flows into the connecting duct 933 communicating with the downstream duct 932. The connection duct 933 allows the upstream duct 931 and the downstream duct 932 to communicate with each other, and the air flowing out from the downstream duct 932 returns to the upstream duct 931 via the connection duct 933.

  By such an operation, the opening surface 61 on the operation unit side and the opening surface 62 on the non-operation unit side are shielded by the air curtain. Thereby, it is possible to suppress the fine particles, odor components, and the like discharged from the discharge unit 63 from flowing out of the space 6. In addition, since the heated air (hot air) discharged | emitted from the discharge part 63 can also be interrupted | blocked by an air curtain, a user is hard to feel discomfort.

  In the air curtain generator 9, the two air blowers 94 and 96 are used to generate airflow in the duct portion 93. However, as long as the airflow having a sufficient flow rate to generate the air curtain can be secured. A single blower may be used. Moreover, in order to reduce noise and vibration, three or more blowers may be used.

  In the image forming apparatus 1, when an image is formed on a small number of recording papers, the amount of discharged fine particles, odor components, etc. is not or small, and the user does not feel uncomfortable. Therefore, in the image forming apparatus 1, when an image is continuously formed (printed) on a predetermined number or more of recording sheets, the air curtain generator 9 is operated to shield the opening surfaces 61 and 62 of the space 6. Also good. In the image forming apparatus 1, when the fixing temperature control in the image forming unit 5 exceeds a certain level, a large amount of fine particles, odor components, etc. are generated, and are discharged from the discharge unit 63 into the space on the air flow generated by the fixing. It becomes easy to be done. Therefore, in the image forming apparatus 1, the fixing temperature control is measured, and when the temperature reaches a certain temperature, the suction side blower 94 and the blowout side blower 96 are driven to shield the opening surfaces 61 and 62 of the space 6. An air curtain to be generated may be generated. By doing so, it is possible to suppress the spraying of fine particles, odorous components, and the like to the user, and to reduce power consumption.

  Further, in the image forming apparatus 1, a detection unit (sensor) that detects that a user's hand is inserted into the space 6 is attached, and when the user's hand is inserted into the space 6, It is good also as a structure which stops production | generation. With this configuration, it is possible to prevent the recording paper P2 from being disturbed by the air blown from the air outlet 91 being blown onto the recording paper P2 placed on the paper discharge tray 60.

  Although the air curtain production | generation apparatus 9 of this embodiment is made into the circulation type which returns the air suck | inhaled by the suction part 92 to the blower outlet 91 using the duct part 93, it is not limited to this. For example, the air sucked from the suction portion 92 and flowing into the downstream duct 932 may be discharged from the apparatus body 2 to the outside so as not to be blown by the user. Further, the duct portion 93 may be piped so that the air flowing through the duct portion 93 is used to cool the inside of the image forming apparatus.

  In the air curtain generating device 9 of the present embodiment, both the opening surface 61 on the operation unit side on the front surface of the space 6 and the opening surface 62 on the left non-operation unit side are shielded by the air curtain. Is not to be done. It is sufficient that fine particles, odor components, and the like discharged from the discharge unit 63 are not sprayed by the user operating the operation unit, and the air outlet 91 is configured so that only the opening surface 61 on the operation unit side is shielded by the air curtain. (911) may be arranged. Even when the opening surface 62 on the non-operation part side is not shielded by the air curtain, a suction pipe 97 having an upper end opening may be provided on the left side of the bottom surface of the space 6. By forming in this way, fine particles, odor components, and the like in the vicinity of the opening surface 62 on the non-operation portion side of the space 6 can be sucked by the suction pipe 97, so that the fine particles, odor components, etc. 2 can be suppressed from flowing out.

  In this embodiment, although the air curtain production | generation apparatus 9 is set as the structure which sprays air toward the lower part from the upper part of the space 6, and produces | generates an air curtain, it is not limited to this. For example, the structure which sprays air toward the upper part from the lower part may be sufficient. In addition, when the opening surface of the space 6 is one surface, or when there is a column top at the corner between the opening surface 61 on the operation unit side and the opening surface 62 on the non-operation unit side, the opening surface is laterally or obliquely An air curtain may be generated by an airflow flowing in the direction.

  What is discharged from the inside of the main body of the image forming apparatus 1 is not limited to fine particles and odor components. For example, it is interpreted that hot air and off-flavors are included. VOC (Volatile Organic Compounds) and UFP (Ultra Fine Particles) are also included. Moreover, it is not limited to these, It is interpreted that a contact with a user can be interrupted | blocked with an air curtain.

  The image forming apparatus according to the present invention has been described by taking an example of an electrophotographic image forming apparatus. However, the image forming apparatus is not limited to the electrophotographic system as long as it includes an air curtain generating device in the above-described embodiment. An image forming apparatus using another method such as an ink jet method may be used. The image forming apparatus according to the present invention may be an MFP (Multifunction Peripheral) having a copy function, a scanner function, a printer function, and a fax function as long as the image forming apparatus includes the air curtain generator in the above-described embodiment. Alternatively, it may be a printer, a copier, a facsimile, or the like. In addition, the structure of each part is not limited to embodiment of illustration, A various change is possible in the range which does not deviate from the meaning of this invention.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Apparatus main body 21 Upper part 22 Lower part 23 Rear wall part 24 Whole surface cover 241 Louver 3 Image reading part 4 Drawing apparatus 41 Paper feed cassette 411 Front cover 412 Recording paper storage part 413 Bottom board 414 Push-up board 5 Image formation part 6 Space 60 Discharge tray 61 Opening surface on the operation unit side 62 Opening surface on the non-operation unit side 63 Discharge unit 7 Operation panel 8 Paper feed mechanism 81 Feeding roller 82 Paper feed roller 83 Rolling roller 84 Paper discharge roller pair 85 Circulation transport unit 86 Manual feed tray 9 Air curtain generator 91 Air outlet 92 Suction portion 921 First surface 922 Second surface 923 Inclined surface 924 Opposed inclined surface 93 Duct portion 931 Upstream duct 932 Downstream duct 933 Connection duct 94 Suction side blower 95 Filter 96 Blower side blower 97 Suction pipe

Claims (20)

An image forming unit disposed in an intermediate portion in the vertical direction of the main unit;
An image reading unit disposed on an upper portion of the main body,
A paper discharge tray provided on a bottom surface of a space between the image forming unit and the image reading unit and on which recording paper on which an image is formed by the image forming unit is placed;
An operation unit for receiving an operation input,
The space has an opening surface on the operation unit side that is opened at least on a surface of the main body portion where the operation unit is provided,
An air outlet that blows out air to generate a layer of air that shields the opening surface on the operation unit side;
2. The image forming apparatus according to claim 1, wherein the air outlet blows air toward an outside of a region where the largest recording sheet of the paper discharge tray is stacked.   The image forming apparatus according to claim 1, wherein the air outlet is provided so as to flow an airflow in a vertical direction. The space includes a paper discharge unit that is provided on one of the left and right surfaces adjacent to the opening surface on the operation unit side of the space and discharges the recording paper.
The image forming apparatus according to claim 2, wherein the blower outlet has an opening area that is closer to the paper discharge unit.   The image forming apparatus according to claim 2, wherein the air outlet is a long hole extending along an opening surface on the operation unit side. The space has an opening surface on the non-operation portion side on a surface different from the surface on which the operation portion of the main body portion is provided,
The image forming apparatus according to claim 1, wherein the air outlet is provided at a position that generates an airflow that shields the opening surface on the non-operation unit side. A suction portion that is provided opposite to the blowout port and sucks the blown air;
A duct portion that communicates with the suction portion and through which the air sucked from the suction portion flows,
The image forming apparatus according to claim 1, wherein the duct portion is disposed inside the main body portion.   The image forming apparatus according to claim 6, wherein an opening area of the suction portion is larger than an opening area of the air outlet. The suction portion has a first surface disposed on the discharge tray side, and a second surface facing the first surface with a gap therebetween,
The first surface is provided with a slope having an inclination in which the downstream side in the air flow direction approaches the second surface side,
The image forming apparatus according to claim 6, wherein the second surface is provided with an opposing inclined surface disposed to face the inclined surface.   The image forming apparatus according to claim 6, wherein a part of the duct portion is included in an openable / closable cover provided in the main body portion.   The image forming apparatus according to claim 6, wherein a blower that generates an airflow sucked from the suction portion is provided inside the duct portion.   The duct part is opposite to the operation part of the main body part below the area opposite to the paper discharge part in the space outside the area where the largest recording sheet of the paper discharge tray is stacked in plan view. The image forming apparatus according to claim 10, wherein the blower is provided close to a side of the duct portion opposite to the operation portion.   The image forming apparatus according to claim 10, wherein a flow rate of air sucked from the suction portion is larger than a flow rate of air blown from the blower outlet.   The image forming apparatus according to claim 10, wherein a filter is provided inside the duct portion.   The image forming apparatus according to claim 10, wherein the duct portion has a circulation path that returns air sucked from the suction portion to the outlet. The air outlet is provided on the upper surface of the space, and the suction portion is provided on the lower surface of the space,
The upper end of the inclined surface is below the lower end of the paper discharge tray, and the upper end of the opposed inclined surface is above the upper end of the inclined surface. Image forming apparatus. At least one suction pipe that communicates the upper surface of the discharge tray and the duct portion is provided;
16. The opening at the upper end of the suction pipe is at a position lower than the surface on which the recording paper of the paper discharge tray is placed outside the area where the maximum recording paper of the paper discharge tray is stacked. Image forming apparatus.   17. The image forming apparatus according to claim 16, wherein a flow path cross-sectional area of the suction pipe is narrower on the downstream side in the airflow direction than on the upstream side.   The image forming apparatus according to claim 1, wherein air is blown out from the air outlet when the fixing temperature control in the image forming unit is equal to or higher than a predetermined temperature.   18. The image forming apparatus according to claim 10, wherein when the fixing temperature control in the image forming unit is equal to or higher than a predetermined temperature, air is blown out from the blowout port and air is sucked in from the suction unit. The image forming apparatus according to claim 12, wherein a sum of a flow rate of air sucked from the suction portion and a flow rate of air blown from the blower outlet is larger near the paper discharge portion.

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