Image forming apparatus

Abstract

To suppress such a malfunction that a user inadvertently touches an intake fan, or perceives operating noise of the intake fan as disturbing noise.SOLUTION: A lateral projecting part 116 provided with a first sheet discharge path K1 and a first sheet discharge port H1 protrudes upward from a lateral side of an image forming part 115 and is arranged adjacently to a first sheet placing part 134. A depth side projecting part 117 which forms a space W together with the image forming part 115 and the lateral projecting part 116 protrudes upward from a depth side of the image forming part 115 and is arranged adjacently to the first sheet placing part 134. A blower unit 136 which takes in air from a side facing the depth side projecting part 117 and exhausts the air toward a sheet P discharged from the first sheet discharge port H1 to the first sheet placing part 134 is disposed in the space W so as to face the depth side projecting part 117 at the front side.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile machine, or a combination machine thereof. [Background technology]

[0002] Conventionally, in image forming devices such as copiers and printers, a sheet placing section is formed above the image forming section so as to be surrounded by multiple wall sections (side protrusions and rear protrusions) (see, for example, Patent Document 1). More specifically, after an image is formed in the image forming unit, the sheet is discharged from the sheet discharge outlet via a sheet discharge path in a lateral protrusion that protrudes upward from the side of the image forming unit, and is stacked in the sheet stacking unit.

[0003] Meanwhile, Patent Document 1 discloses a technology in which a mechanism for exhausting air toward sheets discharged toward a first discharge tray (sheet placement section) is installed in a second discharge tray (second sheet placement section) disposed above the first discharge tray, with the aim of cooling the sheets discharged toward the first discharge tray. This second discharge tray is configured to take in air by an intake fan through an intake port formed on the side opposite the position where the lateral protrusion is installed, and exhaust the air from above toward the sheets discharged toward the first discharge tray. Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology of Patent Document 1, the intake fan and air intake port are located close to the front (near side) where the user operates the image forming device, which causes problems such as the user accidentally touching the intake fan or the user perceiving the operating sound of the intake fan as noise.

[0005] This invention has been made to solve the above-mentioned problems, and aims to provide an image forming apparatus that is less likely to cause problems such as a user accidentally touching the intake fan or a user perceiving the operating sound of the intake fan as noise. [Means for solving the problem]

[0006] The image forming apparatus of the present invention includes an image forming unit that forms an image on a sheet, The printer comprises a sheet mounting section that is arranged above the image forming section and is capable of stacking sheets on which an image has been formed in the image forming section; a lateral protrusion that protrudes upward from the side of the image forming section and is arranged adjacent to the sheet mounting section, and is provided with a sheet discharge path for transporting sheets on which an image has been formed in the image forming section and a sheet discharge outlet for discharging the sheets toward the sheet mounting section; a rear protrusion that protrudes upward from the rear side of the image forming section and is arranged adjacent to the sheet mounting section, and forms a space together with the image forming section and the lateral protrusion; and an air blowing unit that is arranged in the space opposite the rear protrusion on the front side and exhausts air that has been taken in from the side opposite the rear protrusion toward the sheets that are discharged from the sheet discharge outlet toward the sheet mounting section. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an image forming apparatus that is less likely to cause problems such as a user accidentally touching the intake fan or a user perceiving the operating sound of the intake fan as noise. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is an overall configuration diagram showing an image forming apparatus according to an embodiment of the present invention; [Figure 2] FIG. 1 is a perspective view showing an image forming apparatus. [Figure 3] FIG. [Figure 4]FIG. 2 is a view of the internal space of the image forming apparatus as seen from the left side. [Figure 5] FIG. 4 is a diagram showing the flow of air in the blower unit. [Figure 6] 10 is a perspective view showing the second sheet placement portion and the air blowing unit from diagonally below. FIG. [Figure 7] FIG. 4 is a perspective view showing the second sheet placement portion and the air blowing unit from diagonally above. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are designated by the same reference numerals, and redundant explanations will be appropriately simplified or omitted.

[0010] The overall configuration and operation of an image forming apparatus 1 according to this embodiment will be described with reference to FIGS. As shown in Figures 1 and 2, in the image forming apparatus 1 of this embodiment, a space W (internal space) surrounded by a side protrusion (also a side wall portion) 116 and a rear protrusion (also a rear wall portion) 117 is formed below the document transport device 110 (and the document reading device 102) and above the image forming unit 115. This space W (internal space) is a space in which sheets P (sheets P after image formation (printing)) discharged from the image forming device 1 can be discharged and stacked, and is also a space in which the discharged and stacked sheets P can be removed.

[0011] The internal space W is formed with a first space W1 and a second space W2 separated above the first space W1 by a second sheet placement section 135 (reversal tray). The first space W1 is provided with a first sheet loading section 134 as a sheet loading section capable of loading printed sheets P, and the printed sheets P are stacked sequentially on the sheet loading surface 134a of the first sheet loading section 134. The second space W2 is a space into which the sheet P is temporarily discharged, mainly in double-sided printing mode, in order to invert the sheet P after the front side has been printed. In this embodiment, the second space W2 can also function as a space for loading the printed sheet P in a location different from the first sheet loading section 134, and in such a case, the printed sheets P are stacked one after another on the second sheet loading section 135 (inversion tray). In this embodiment, an air blowing unit 136 for cooling the sheets P stacked on the first sheet stacking section 134 is provided in the internal space W, which will be described in detail later.

[0012] Referring to Figure 1, the image forming device 1 has an image forming unit 115 and main body feed trays 112, 113, etc., located below the internal space W (in the -Z direction), a lateral protrusion 116 located to the side of the internal space W (in the -X direction, on the right side of Figure 1), a rear protrusion 117 (see Figure 2) located at the rear side of the internal space W (in the +Y direction, on the rear side perpendicular to the paper surface of Figure 1), and a document transport device 110, a document reading device 102, etc., located above the internal space W. The image forming section 115 includes a writing device 103, image creating sections 104Y, 104M, 104C, and 104K, an intermediate transfer belt 178, a secondary transfer roller 189, a fixing section 120, and the like. An operation display panel 149 (operation display unit) for displaying various information about the image forming apparatus 1 and inputting various commands is provided on the exterior of the image forming apparatus 1. The side of the operation display panel 149 that an operator such as a user faces directly and operates or views the display is the front side (near side) of the image forming apparatus 1. Therefore, the internal space W is open on the front side and the left side when viewed from the front of the image forming apparatus 1.

[0013] Hereinafter, the image forming operation (printing operation) in the image forming apparatus 1 will be described with reference to FIG. First, the document D is transported (fed) from the document table in the direction of the arrow in the drawing by the transport rollers of the document transport device 110, and passes over the document reading device 102. At this time, the document reading device 102 optically reads image information of the document D passing above. The optical image information read by the document reading device 102 is converted into an electrical signal and then transmitted to the writing device 103. Then, the writing device 103 emits laser light based on the image information of the electrical signal onto the photosensitive drums 105Y, 105M, 105C, and 105K for each color, thereby carrying out an exposure process. Then, a charging process, an exposure process, and a development process are performed on the photosensitive drums 105Y, 105M, 105C, and 105K of the image forming units 104Y, 104M, 104C, and 104K, respectively, and desired images are formed on the photosensitive drums 105Y, 105M, 105C, and 105K, respectively. Thereafter, the images formed on the photosensitive drums 105Y, 105M, 105C, and 105K are transferred onto the intermediate transfer belt 178 in a superimposed state as a color image. Furthermore, the color image formed on the intermediate transfer belt 178 is transferred, at a position facing the secondary transfer roller 189 (secondary transfer nip), onto the sheet P that is fed and conveyed from one of the two main body feed trays 112 and 113 to the sheet feeding path K0 by the feed roller 197. Thereafter, the sheet P onto which the color image has been transferred is conveyed to the position of the fixing unit 120. Then, the color image transferred to the front surface is fixed onto the sheet P (a fixing process). Then, the sheet P (printed sheet P) after an image has been formed by the image forming section 115 passes through the first sheet discharge path K1 (sheet discharge path) of the lateral protrusion 116, is discharged from the first sheet discharge outlet H1 (sheet discharge outlet) by the first discharge roller 131, and is stacked on the first sheet loading section 134 (sheet loading section) in the first space W1.

[0014] When a "duplex printing mode" is selected, which prints on both sides (front and back sides) of the sheet P, the sheet P, after the fixing process on the front side has been completed, is guided to the second sheet discharge path K2 (sheet relay path) by the operation of the switching claw, rather than being discharged directly from the image forming apparatus 1 as in the "single-sided printing mode" described above. The sheet P guided to the second sheet discharge path K2 is then guided to the sheet reversal path K3. At this time, the rear end of the sheet P is held between the second discharge rollers 132 (reversal rollers), and the other portion is discharged from the second sheet discharge opening H2 into the second space W2. The sheet P is then switched back by the reverse rotation of the second discharge rollers 132 and conveyed toward the duplex conveyance path K4. Then, the sheet P guided to the double-sided conveying path K4 is conveyed again toward the position of the secondary transfer nip (secondary transfer roller 189). Then, at the position of the secondary transfer nip, an image is formed (printed) on the back side of the sheet P by the same image forming process (image forming operation) as described above, and then the sheet P undergoes a fixing process in the fixing unit 120, and is discharged from the first sheet discharge port H1 via the first sheet discharge path K1 into the first space W1, and is stacked on the first sheet loading unit 134.

[0015] The characteristic configuration and operation of the image forming apparatus 1 according to this embodiment will be described in detail below. As previously explained using Figures 1 and 2, the image forming apparatus 1 is provided with an image forming section 115, a side protrusion 116, a rear protrusion 117, a first sheet placing section 134 as a sheet placing section, a second sheet placing section 135 (reversal tray), an air blowing unit 136, and the like.

[0016] The image forming section 115 is a section that forms an image on the sheet P. The first sheet placing section 134 as a sheet placing section is disposed above the image forming section 115 and is configured to be able to stack sheets P after images have been formed in the image forming section 115. In this embodiment, the sheet placing surface 134a of the sheet placing section 134 is formed as an inclined surface that slopes upward from the upstream side toward the downstream side in the sheet discharge direction (+X direction). Also, as shown in Fig. 4, the sheet placing surface 134a is formed in a convex shape so that the center in the width direction (±Y direction) is higher than both end portions. 1 to 4, etc., second sheet placing section 135 (reversal tray) is surrounded by lateral protrusion 116 and rear protrusion 117 above space W (first space W1) that functions as first sheet placing section 134. Also referring to FIGS. 6 and 7, second sheet placing section 135 in this embodiment is a tray-shaped member whose side closer to lateral protrusion 116 is curved into a curved surface.

[0017] 1 to 5, the lateral protrusion 116 protrudes upward from a lateral side (in the -X direction, on the right side in FIG. 1) of the image forming unit 115 (or the image forming apparatus 1) and is disposed adjacent to the first sheet placing unit 134 (and the second sheet placing unit 135). The lateral protrusion 116 is provided with a first sheet ejection path K1 as a sheet ejection path for transporting the sheet P after an image has been formed in the image forming unit 115, a first sheet ejection outlet H1 as a sheet ejection outlet for ejecting the sheet P toward the first sheet placing unit 134, a second sheet ejection path K2 capable of transporting the sheet P after an image has been formed in the image forming unit 115, and a second sheet ejection outlet H2 capable of ejecting the sheet P toward the second sheet placing unit 135. The positional relationship between the image forming unit 115 and the lateral protrusion 116 includes a positional relationship in which the image forming unit 115 and the lateral protrusion 116 at least partially overlap in the up-down direction at the end side (side side) in the width direction (X direction, left-right direction in FIG. 1) of the image forming apparatus. It also includes a positional relationship in which the image forming unit 115 and the lateral protrusion 116 are lined up on the left and right in the width direction of the image forming apparatus. The rear protrusion 117 is disposed so as to protrude upward from the rear side (+Y direction) of the image forming unit 115 (or the image forming apparatus 1) and be adjacent to the first sheet placing unit 134 (and the second sheet placing unit 135). The rear protrusion 117, together with the image forming unit 115 and the lateral protrusion 116, forms a space W (internal space) that functions as the first sheet placing unit 134 (and the second sheet placing unit 135). The positional relationship between image forming unit 115 and rear-side protrusion 117 includes a positional relationship in which image forming unit 115 and lateral protrusion 116 at least partially overlap in the vertical direction at the rear side in the depth direction of the image forming device (Y direction, the direction perpendicular to the paper surface of FIG. 1). It also includes a positional relationship in which image forming unit 115 and lateral protrusion 116 are lined up on the left and right in the depth direction of the image forming device.

[0018] 4, 5, etc., the air blowing unit 136 is arranged in the space W (internal space) so as to face the front side (-Y direction) of the rear-side protrusion 117. This air blowing unit 136 takes in air from the side facing the rear-side protrusion 117 and exhausts it toward the sheets P being discharged from the first sheet discharge opening H1 (sheet discharge opening) toward the first sheet placing section 134 (sheet placing section) (including not only the sheets P being discharged but also the sheets P after being placed on the first sheet placing section 134). Specifically, as shown in Figure 5, in the blower unit 136, the first air intake 136a1 and the intake fan 136x for taking in air from the side of the rear protrusion 117 are positioned on the rear side (+Y direction) away from the front side (-Y direction) which is the front side for the user.

[0019] Specifically, the intake fan 136x and the first intake port 136a1 (intake port) of the blower unit 136 are disposed closer to the front (-Y direction) than the rear-side protrusion 117 and further rearward (+Y direction) than the sheets P stacked on the first sheet loading section 134. Specifically, the blower unit 136 is screwed (fixed) to the second sheet loading section 135 at points A and B (see FIGS. 3 and 6). Also, referring to Figures 6, 7, etc., the blower unit 136 is installed integrally below (-Z direction) and at the rear side (+Y direction) of the second sheet loading section 135 (reversal tray), and is configured to exhaust air from above toward the sheet P (and the sheet P on the first sheet loading section 134) being discharged from the first sheet discharge outlet H1 toward the first sheet loading section 134.

[0020] By providing the air blowing unit 136 in this manner, the sheets P discharged and placed on the first sheet placing section 134 are cooled, and therefore, compared to when this is not the case, the toner image on the sheets P acts as a binder, making it less likely that the sheets P stacked on the first sheet placing section 134 will stick together. Furthermore, since the blower unit 136 in this embodiment is configured to mainly draw air from the rear side of the image forming apparatus 1 (since the intake fan 136x and the first air intake 136a1 are located at the rear side), problems such as the user accidentally touching the intake fan 136x or the user perceiving the operating sound of the intake fan 136x as noise are less likely to occur. In particular, in this embodiment, the blower unit 136 is positioned in front of the rear protrusion 117, at the rear of the internal space W, making it even more difficult for the user to access the intake fan 136x, and also making it more difficult for the operating noise of the intake fan 136x to reach the front of the image forming apparatus 1 where the user is standing. Furthermore, in this embodiment, since the intake fan 136x is installed near the first intake port 136a1, the intake efficiency (amount of intake air) is high (large), and the cooling effect on the sheet P can be improved.

[0021] More specifically, with reference to FIGS. 3 to 7, the blower unit 136 is provided with a duct 136a, a first intake port 136a1, a second intake port 136a2, an intake fan 136x, an exhaust port 136a3, and the like. Duct 136a is formed with a first intake port 136a1, a second intake port 136a2, an exhaust port 136a3, and the like. First air intake port 136a1 is a main air intake port that opens at a position facing rear-side protrusion 117 with a gap δ (see FIGS. 4 and 5) therebetween and takes air into duct 136a from gap δ. In this embodiment, first air intake port 136a1 opens in a circular shape with a diameter substantially equal to the fan diameter of intake fan 136x and faces the vertical wall portion of rear-side protrusion 117 with a gap δ therebetween. The second air intake 136a2 is a secondary air intake that opens toward the side (+X direction) opposite the side where the lateral protrusion 116 is arranged in the internal space W (first space W1) and takes air into the inside of the duct 136a. In this embodiment, with reference to Figures 4 and 5, the second air intake 136a2 is a plurality of slits that open in a plane parallel to the side of the image forming apparatus main body 1 (the side of the main body cover on the right side) and prevents the user from accidentally inserting their fingers. The intake fan 136x is disposed so as to face the first intake port 136a1 on the near side (-Y direction). The intake fan 136x is a fan for sucking air from the first intake port 136a1 and the second intake port 136a2, and is either installed inside the duct 136a or sandwiched between multiple ducts 136a. The exhaust port 136a3 is an opening for discharging air drawn in by the intake fan 136x through the duct 136a. The portion of the duct 136a where the exhaust port 136a3 is formed is formed below the second sheet loading section 135 (reversal tray) so as to extend from the rear side (+Y direction) to the front side (-Y direction). A plurality of exhaust ports 136a3 are formed at intervals in the width direction (the vertical direction in FIG. 5) in order to cool the sheet P across the width direction. In the blower unit 136 configured in this manner, air taken in from the outside flows in the duct 136a in the direction indicated by the arrow in FIG. 5, and is finally exhausted from the exhaust port 136a3 in the direction indicated by the arrow in FIG.

[0022] In this embodiment, the gap δ (the gap in the ±Y directions) between the first intake port 136a1 and the rear protrusion 117 described above is preferably set to 2 mm or more. It is more preferable that the gap δ be set to approximately 2 to 10 mm. This is because the inventors of the present application conducted an experiment to confirm the relationship between the size of the gap δ and the cooling performance for the sheet P and found that when the gap δ is 1.5 mm or more, the cooling performance for the sheet P is gradually exerted, and when the gap δ is 2 mm or more, the cooling performance for the sheet P is sufficiently exerted. It should be noted that if the gap δ exceeds 10 mm, the operating noise of the intake fan 136x gradually leaks out to the outside, so it is more preferable to set the upper limit of the gap δ to 10 mm.

[0023] Moreover, blower unit 136 in this embodiment is configured so that the amount of air taken in from first air intake port 136a1 is greater than the amount of air taken in from second air intake port 136a2. The first air intake port 136a1 is provided near the air intake fan 136x, and therefore can ensure a larger amount of air intake than the second air intake port 136a2, which is located away from the air intake fan 136x. However, second air intake port 136a2 is located sufficiently far from sheet P (sheet P heated by fixing unit 120) on first sheet loading section 134 and is located at a position where it can sufficiently take in outside air from image forming apparatus 1, making it easy to take in relatively low-temperature outside air. First air intake port 136a1 is located downstream of second air intake port 136a2 in the flow direction of the intake air. Therefore, inside duct 136a, the air taken in from first air intake port 136a1 is cooled by the air taken in from second air intake port 136a2, and the temperature of the air discharged from exhaust port 136a3 is lower than when air is taken in only from first air intake port 136a1, thereby improving cooling performance for sheet P. In this embodiment, both the first air intake 136a1 and the second air intake 136a2 are positioned not directly above the sheets P stacked on the first sheet loading section 134. Therefore, compared to when the first and second air intakes 136a1, 136a2 are positioned directly above the sheets P, the problem of taking in some or all of the heat from the sheets P as it rises is reduced.

[0024] 3 and the like, in the blower unit 136 of this embodiment, it is preferable that the positions of the first air intake 136a1 and the air intake fan 136x in the sheet discharge direction (±X direction) approximately coincide with the position of the inclined surface of the sheet loading surface 134a, as shown in FIG. By arranging them in this manner, it becomes possible to enlarge the first air intake 136a1 and the air intake fan 136x in terms of layout by the amount of the downwardly sloping surface on the sheet placing surface 134a, thereby improving the cooling performance of the air blowing unit 136.

[0025] Furthermore, in this embodiment, the second sheet loading section 135 (to which the air blowing unit 136 is integrated by screwing) is not tightly fixed to the image forming apparatus main body 1 by screwing, but is fixed relatively loosely (semi-fixed) by a method other than screwing. As a specific example, the portions R1 and R2 surrounded by dashed lines in Figure 3 are fixed positions, and the second sheet placing portion 135 can be removably held on the lateral protrusion 116 and the rear protrusion 117 with its insertion portion inserted into an insertion receiving portion formed on at least one of the lateral protrusion 116 and the rear protrusion 117. With this configuration, compared to when the second sheet placing section 135 is tightly fixed to the image forming apparatus main body 1, vibrations caused by the air blowing unit 136 (intake fan 136x) during operation are less likely to be transmitted to the image forming apparatus main body 1 via the second sheet placing section 135. This reduces the problem of abnormal images, such as banding, caused by vibrations in the image forming section 115.

[0026] 3, in the image forming apparatus 1 of the present embodiment, a sheet detection sensor 133 serving as a detection means for detecting the presence or absence of a sheet P passing near the first sheet discharge outlet H1 (sheet discharge outlet) is installed in the lateral protrusion 116. This sheet detection sensor 133 (detection means) is a reflective photosensor that optically detects whether or not a sheet P is present at that position. When multiple sheets P are successively discharged from the first sheet discharge outlet H1, the intake fan 136x is controlled so that it starts operating after a first predetermined time T1 has elapsed since the leading edge of the first sheet P is detected by the sheet detection sensor 133 (detection means), and stops operating after a second predetermined time T2 has elapsed since the trailing edge of the last sheet P is detected by the sheet detection sensor 133. By controlling the intake fan 136x in this way, the device can save energy compared to when the intake fan 136x is constantly running. In this embodiment, the first and second predetermined times T1 and T2 are both set to 0 seconds, but the first and second predetermined times T1 and T2 can also be set to other times.

[0027] As described above, the image forming apparatus 1 in this embodiment is provided with an image forming unit 115 that forms an image on a sheet P, and a first sheet placing unit 134 (sheet placing unit) that can stack the sheet P after the image has been formed in the image forming unit 115 is disposed above the image forming unit 115. In addition, the side protrusion 116 that is provided with a first sheet discharge path K1 (sheet discharge path) that transports the sheet P after the image has been formed in the image forming unit 115 and a first sheet discharge outlet H1 (sheet discharge outlet) that discharges the sheet P toward the first sheet placing unit 134 protrudes upward from a side of the image forming unit 115 and is disposed adjacent to the first sheet placing unit 134. In addition, the rear protrusion 117 that forms a space W together with the image forming unit 115 and the side protrusion 116 protrudes upward from the rear side of the image forming unit 115 and is disposed adjacent to the first sheet placing unit 134. Furthermore, an air blowing unit 136 that exhausts air taken in from the side opposite the rear protrusion 117 toward the sheet P discharged from the first sheet discharge outlet H1 toward the first sheet loading section 134 is arranged in the space W so as to face the front side of the rear protrusion 117. This reduces the likelihood of a user accidentally touching the intake fan 136x or of the user perceiving the operating sound of the intake fan 136x as noise.

[0028] It is to be noted that the present invention is not limited to the present embodiment, and it is clear that the present embodiment can be appropriately modified within the scope of the technical concept of the present invention in addition to the modifications suggested in the present embodiment. Furthermore, the number, position, shape, etc. of the components are not limited to the present embodiment, and the number, position, shape, etc. of the components can be any number, position, shape, etc. that is suitable for implementing the present invention.

[0029] In this specification, directions (sides) and surfaces such as "rear side," "side," "near side," and "rear" refer to the direction (side) that a user or other worker faces when performing normal operations on the image forming apparatus, defined as "near side" or "front." [Explanation of symbols]

[0030] 1 Image forming apparatus (image forming apparatus main body), 115 image forming unit, 116 Lateral projection; 117 Back protrusion, 133 sheet detection sensor (detection means), 134 first sheet placement section (sheet placement section), 134a sheet placement surface; 135 second sheet placement section, 136 Blower unit, 136a duct, 136a1 First intake port, 136a2 Second intake port, 136a3 exhaust outlet, 136x intake fans, δ gap, K1 First discharge route (discharge route), K2 second discharge route, H1 1st discharge port (discharge port), H2 2nd outlet, W space (body space), W1 First space, W2 Second space, P sheet (recording medium).

[0031] The present invention can also be embodied in a combination of Supplementary Notes 1 to 11, for example, as follows. (Appendix 1) an image forming unit that forms an image on a sheet; a sheet stacking section disposed above the image forming section and capable of stacking sheets on which images have been formed by the image forming section; a lateral protrusion portion that protrudes upward from a lateral side of the image forming portion and is disposed adjacent to the sheet placing portion, and that is provided with a sheet discharge path for conveying a sheet on which an image has been formed by the image forming portion, and a sheet discharge opening for discharging the sheet toward the sheet placing portion; a rear-side protruding portion that protrudes upward from a rear side of the image forming portion and is disposed adjacent to the sheet stacking portion, and that forms a space together with the image forming portion and the side protruding portion; an air blowing unit that is disposed in the space so as to face the rear-side protrusion on the front side, and that exhausts air taken in from the side facing the rear-side protrusion toward the sheets that are discharged from the sheet discharge port toward the sheet placement unit; An image forming apparatus comprising: (Appendix 2) a second sheet placement portion surrounded by the side protrusion and the rear protrusion above the space, the lateral protrusion is provided with a second sheet discharge path capable of conveying a sheet on which an image has been formed by the image forming unit, and a second sheet discharge opening capable of discharging the sheet toward the second sheet placing unit, The image forming apparatus described in Appendix 1 is characterized in that the air blowing unit is integrally installed below the second sheet loading section and exhausts air from above toward sheets being discharged from the sheet discharge outlet toward the sheet loading section. (Appendix 3) The image forming device described in Appendix 2 is characterized in that the second sheet placing portion is detachably held by the side protrusion and the rear protrusion with its insertion portion inserted into an insertion receiving portion formed on at least one of the side protrusion and the rear protrusion. (Appendix 4) The blower unit is Duct and a first air intake port that opens at a position opposite to the rear protrusion with a gap therebetween and takes in air into the duct through the gap; a second air intake port that opens toward a side opposite to the side where the lateral protrusion is disposed in the space and takes in air into the duct; an intake fan disposed on a front side opposite to the first intake port and configured to draw air from the first intake port and the second intake port; the exhaust port that exhausts the air taken in by the intake fan through the duct; 4. The image forming apparatus according to claim 1, further comprising: (Appendix 5) 5. The image forming apparatus according to claim 4, wherein the gap is 2 mm or more. (Appendix 6) the second air intake port is a plurality of slits that open in a plane parallel to a side surface of the image forming apparatus body, 6. The image forming apparatus according to claim 4, wherein the exhaust port is formed in a plurality of locations spaced apart in the width direction. (Appendix 7) 7. The image forming apparatus according to claim 4, wherein the amount of air taken in from the first air intake port is greater than the amount of air taken in from the second air intake port. (Appendix 8) The image forming apparatus according to any one of Supplementary Note 4 to Supplementary Note 7, wherein the first intake port is located downstream of the second intake port in the flow direction of the intake air. (Appendix 9) the sheet placement surface of the sheet placement section includes an inclined surface that slopes upward from the upstream side to the downstream side in the sheet discharge direction, The image forming apparatus according to any one of appendixes 4 to 8, wherein the positions of the first intake port and the intake fan in the sheet discharge direction substantially coincide with the position of the inclined surface. (Appendix 10) An image forming apparatus as described in any one of Appendix 4 to Appendix 9, characterized in that the first air intake and the second air intake are both positioned at a position that is not directly above the sheets stacked in the sheet loading section. (Appendix 11) the side protrusion includes a detection means for detecting the presence or absence of a sheet passing near the sheet discharge port, The image forming apparatus according to any one of appendices 4 to 10, characterized in that when multiple sheets are successively discharged from the sheet discharge outlet, the intake fan starts operating after a first predetermined time has elapsed since the leading edge of the first sheet is detected by the detection means, and stops operating after a second predetermined time has elapsed since the trailing edge of the last sheet is detected by the detection means. (Appendix 12) An image forming apparatus as described in any one of Appendix 1 to Appendix 11, characterized in that the air intake port and air intake fan provided in the air blowing unit are arranged in front of the rear protrusion and rearward of the sheets loaded in the sheet loading section. [Prior art documents] [Patent documents]

[0032] [Patent Document 1] Patent No. 6035213

Claims

1. an image forming unit that forms an image on a sheet; a sheet stacking section disposed above the image forming section and capable of stacking sheets on which images have been formed by the image forming section; a lateral protrusion portion that protrudes upward from a lateral side of the image forming portion and is disposed adjacent to the sheet placing portion, and that is provided with a sheet discharge path for conveying a sheet on which an image has been formed by the image forming portion, and a sheet discharge opening for discharging the sheet toward the sheet placing portion; a rear-side protruding portion that protrudes upward from a rear side of the image forming portion and is disposed adjacent to the sheet stacking portion, and that forms a space together with the image forming portion and the side protruding portion; an air blowing unit that is disposed in the space so as to face the rear-side protrusion on the front side, and that exhausts air taken in from the side facing the rear-side protrusion toward the sheets that are discharged from the sheet discharge port toward the sheet placement unit; An image forming apparatus comprising:

2. a second sheet placement portion surrounded by the side protrusion and the rear protrusion above the space, the lateral protrusion is provided with a second sheet discharge path capable of conveying a sheet on which an image has been formed by the image forming unit, and a second sheet discharge opening capable of discharging the sheet toward the second sheet placing unit, 2. The image forming apparatus according to claim 1, wherein the air blowing unit is integrally installed below the second sheet loading section and exhausts air from above toward the sheets being discharged from the sheet discharge outlet toward the sheet loading section.

3. The image forming apparatus of claim 2, characterized in that the second sheet loading section is detachably held by the side protrusion and the rear protrusion with its insertion portion inserted into an insertion receiving portion formed on at least one of the side protrusion and the rear protrusion.

4. The blower unit is Duct and a first air intake port that opens at a position opposite to the rear protrusion with a gap therebetween and takes in air into the duct through the gap; a second air intake port that opens toward a side opposite to the side where the lateral protrusion is disposed in the space and takes in air into the duct; an intake fan disposed on a front side opposite to the first intake port and configured to draw air through the first intake port and the second intake port; the exhaust port that exhausts the air taken in by the intake fan through the duct; 3. The image forming apparatus according to claim 1, further comprising:

5. 5. The image forming apparatus according to claim 4, wherein the gap is 2 mm or more.

6. the second intake port is a plurality of slits that open in a plane parallel to a side surface of the image forming apparatus body, 5. The image forming apparatus according to claim 4, wherein a plurality of the exhaust ports are formed at intervals in the width direction.

7. 5. The image forming apparatus according to claim 4, wherein the amount of air taken in through the first air intake port is greater than the amount of air taken in through the second air intake port.

8. 8. The image forming apparatus according to claim 7, wherein the first intake port is located downstream of the second intake port in the direction of flow of the intake air.

9. the sheet placement surface of the sheet placement section includes an inclined surface that slopes upward from the upstream side to the downstream side in the sheet discharge direction, 5. The image forming apparatus according to claim 4, wherein the positions of the first intake port and the intake fan in the sheet discharge direction substantially coincide with the position of the inclined surface.

10. 5. The image forming apparatus according to claim 4, wherein both the first air intake and the second air intake are disposed at positions that are not directly above the sheets stacked on the sheet stacking section.

11. the side protrusion includes a detection means for detecting the presence or absence of a sheet passing near the sheet discharge port, 5. The image forming apparatus according to claim 4, wherein when a plurality of sheets are successively discharged from the sheet discharge outlet, the intake fan starts operating after a first predetermined time has elapsed since the leading edge of the first sheet is detected by the detection means, and stops operating after a second predetermined time has elapsed since the trailing edge of the last sheet is detected by the detection means.

12. 3. The image forming apparatus according to claim 1, wherein the air intake port and the air intake fan provided in the blower unit are positioned in front of the rear protrusion and rearward of the sheets loaded in the sheet loading section.

Images