Suction unit, feeder, and image forming apparatus

Abstract

To provide a suction unit that can reduce loss when air passes through a duct.SOLUTION: A suction unit comprises: first blowing means that has an intake port and an exhaust port; second blowing means that has an intake port and an exhaust port; and an air guide member that connects the exhaust port of the first blowing means and the intake port of the second blowing means to each other. The exhaust port of the first blowing means and the intake port of the second blowing means are different in cross-sectional area from each other. The air guide member is formed such that a ridge connecting the exhaust port of the first blowing means and the intake port of the second blowing means is gradually changed.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a suction unit, a feed device, and an image forming apparatus. [Background technology]

[0002] Patent document 1 describes a paper feeding device that includes a separation fan that generates an air flow to separate the paper loaded on the paper loading tray, a suction fan that generates an air flow to suck in the paper loaded on the paper loading tray, and a relay duct that guides air exhausted from the suction fan to the separation fan, the relay duct being formed in a straight line connecting the exhaust port of the suction fan to the intake port of the separation fan. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-154974 A Summary of the Invention [Problem to be solved by the invention]

[0004] In this type of suction unit, it is desirable to reduce losses as the air passes through the ducts. [Means for solving the problem]

[0005] The present invention comprises a first blowing means having an intake port and an exhaust port, a second blowing means having an intake port and an exhaust port, and an air guide member connecting the exhaust port of the first blowing means and the intake port of the second blowing means, wherein the exhaust port of the first blowing means and the intake port of the second blowing means have different cross-sectional areas, and the air guide member is formed by gradually changing the ridge line connecting the exhaust port of the first blowing means and the intake port of the second blowing means. Effect of the Invention

[0006] According to the present invention, it is possible to provide a suction unit capable of reducing loss of air when it passes through a duct. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is an external view of a suction unit according to the embodiment. [Diagram 2] FIG. 2 is an overall configuration diagram showing an example of a suction unit according to the embodiment. [Diagram 3] A cross-sectional view taken along line AA in FIG. 2. [Figure 4] FIG. 2 is an overall perspective view showing an example of a duct. [Diagram 5] FIG. 2 is a schematic configuration diagram illustrating an example of a feed device according to the embodiment. [Figure 6] FIG. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the invention will be described with reference to the drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated explanations will be omitted.

[0009] <Configuration of the suction unit> First, the configuration of the suction unit will be described.

[0010] FIG. 1 is an external view of a suction unit according to an embodiment, where FIG. 1(a) is an overall perspective view showing one configuration example of a suction unit, and FIG. 1(b) is an overall perspective view showing another configuration example of a suction unit.

[0011] In FIG. 1( a ), suction unit 330 includes air blowing unit 331 , air blowing unit 332 , and duct 333 connecting air blowing unit 331 and air blowing unit 332 .

[0012] The blower unit 331 takes in air from an air intake port, which will be described later, in the direction of arrow y1, and exhausts the air from an exhaust port toward the duct 333. The duct 333 connects the blower unit 331 and the blower unit 332 in series, and guides the air sent from the blower unit 331 to the blower unit 332. The blower unit 332 takes in the air guided by the duct 333 from an air intake port, which will be described later, and exhausts the air from the exhaust port 332b in the direction of arrow y2. Thus, in the configuration shown in Fig. 1(a), the air is blown in such a way that the intake direction (arrow y1) and the exhaust direction (arrow y2) are substantially parallel to each other.

[0013] 1(b), the suction unit 330 can be used in combination with an intake port conversion unit 334. The intake port conversion unit 334 includes, for example, an intermediate duct 335 and a chamber 336.

[0014] Intermediate duct 335 connects the air intake of blower unit 331 and chamber 336, and guides air taken in chamber 336 to blower unit 331. Chamber 336 is a hollow body with a box-like or cylindrical appearance, and an opening serving as an air intake is provided at a location where air is to be taken in. For example, when the air intake of chamber 336 is provided at the bottom surface of chamber 336, blower unit 331 takes in air in the direction of arrow z1 through intermediate duct 335 and chamber 336.

[0015] 1(b), the intake direction (arrow z1) and the exhaust direction (arrow y2) are converted to intersect. By using the suction unit 330 in combination with the intake port conversion unit 334, it becomes possible to easily adapt the suction unit 330 to the direction of the part to which air is to be taken or the distance to the part without changing the configuration of the suction unit 330.

[0016] Here, the blower unit 331 is an example of a “first blower means”, and the blower unit 332 is an example of a “second blower means”. The duct 333 is an example of an “air guide member”.

[0017] Fig. 2 is a general configuration diagram showing an example of a suction unit according to an embodiment of the present invention, in which the suction unit 330 shown in Fig. 1(a) is viewed from the front with the exhaust port 332b of the blower unit 332 facing forward.

[0018] Blowing unit 331, which is an example of a first blowing means, includes intake port 331a, exhaust port 331b, and impeller 331c.

[0019] Intake port 331a has, for example, a circular cross-sectional shape and is provided on a side surface of blower unit 331. Exhaust port 331b has, for example, a rectangular cross-sectional shape and is provided on a surface different from the surface having intake port 331a (in this example, a surface perpendicular to the surface having intake port 331a). Impeller 331c can be rotated about rotating shaft 331d, and the rotating surface of impeller 331c is disposed to face intake port 331a.

[0020] Blowing unit 332, which is an example of a second blowing means, includes an intake port 332a, an exhaust port 332b, and an impeller 332c.

[0021] Air intake 332a has, for example, a circular cross-sectional shape and is provided on a side surface of blower unit 331. Air exhaust 332b has, for example, a rectangular cross-sectional shape and is provided on a surface different from the surface having air intake 332a (in this example, a surface perpendicular to the surface having air intake 332a). Impeller 332c can be rotated about rotating shaft 332d, and the rotating surface of impeller 332c is disposed to face air intake 332a.

[0022] The exhaust port 331b of the blower unit 331 and the intake port 332a of the blower unit 332 have different cross-sectional areas, with the intake port 332a having a larger cross-sectional area than the exhaust port 331b. In the embodiment, the exhaust port 331b has a rectangular cross-sectional shape, and the intake port 332a has a circular cross-sectional shape, but the cross-sectional shapes of the exhaust port 331b and the intake port 332a are not limited to these. For example, the exhaust port 331b and the intake port 332a may both be circular or rectangular. However, in this case, the cross-sectional areas are also different.

[0023] The configuration of the impellers 331c, 332c is not particularly limited, and a sirocco fan (blower fan), a centrifugal fan, an axial flow fan, etc. can be used. In the case of a configuration in which the air taken in from the suction ports 331a, 332a is sent out in a direction bent by 90 degrees, as in the suction unit 330 of this embodiment, it is preferable to use a sirocco fan or a centrifugal fan in order to reduce the number of parts and to make the device smaller. Here, the impellers 331c, 332c are an example of an "impeller".

[0024] Duct 333, which is an example of an air guide member, includes first opening 333a connected to exhaust port 331b of blower unit 331 and second opening 333b connected to intake port 332a of blower unit 332. At the connection between blower unit 331 and duct 333, exhaust port 331b and first opening 333a are formed by rectangular openings having substantially the same cross-sectional dimensions. At the connection between blower unit 332 and duct 333, intake port 332a and second opening 333b are formed by circular openings having substantially the same cross-sectional dimensions.

[0025] FIG. 3 is a cross-sectional view taken along line AA in FIG.

[0026] As described above, the impeller 332c of the blower unit 332 is rotatably supported by the rotating shaft 332d, and is disposed so that the rotating surface of the impeller 332c faces the intake port 332a (the second opening 333b of the duct 333).

[0027] When the impeller 332c is viewed from above as shown in the figure, the cross-sectional center of the exhaust port 331b (the first opening 333a of the duct), the cross-sectional center of the intake port 332a (the second opening 333b of the duct), and the rotation axis 332d of the impeller 332 are provided so as to be substantially aligned with each other. This makes it possible to suppress the pressure loss of the air and to reduce the size of the suction unit 330.

[0028] FIG. 4 is an overall perspective view showing an example of a duct.

[0029] As described above, the first opening 333a of the duct 333 is rectangular, whereas the second opening 333b is circular, and thus the duct 333 has different cross-sectional shapes. In this embodiment, the ridgeline of the duct 333 connecting the first opening 333a and the second opening 333b is gradually changed.

[0030] That is, the radius R (r1 to r8) is gradually increased so that the cross-sectional shape of the ridge of the duct 333 changes from a rectangular shape to a circular shape from the first opening 333a to the second opening 333b. By forming the ridge of the duct 333 so that it gradually changes in this manner, the air pressure loss in the suction unit 330 can be further suppressed.

[0031] As described above, this embodiment comprises a blower unit 331 having an intake port 331a and an exhaust port 331b, a blower unit 332 having an intake port 332a and an exhaust port 332b, and a duct 333 connecting the exhaust port 331b of the blower unit 331 and the intake port 332a of the blower unit 332, wherein the exhaust port 331b of the blower unit 331 and the intake port 332a of the blower unit 332 have different cross-sectional areas, and the duct 333 is formed by gradually changing the ridge line connecting the exhaust port 331b of the blower unit 331 and the intake port 332a of the blower unit 332.

[0032] As described above, the exhaust port 331b of the blower unit 331 and the intake port 332a of the blower unit 332 have different cross-sectional shapes.

[0033] These features make it possible to provide a suction unit that can reduce loss of air when it passes through a duct.

[0034] As described above, the blower unit 332 includes the rotatable impeller 332c, and when the impeller 332c is viewed from above, the cross-sectional center of the exhaust port 331b of the blower unit 331, the cross-sectional center of the intake port 332a of the blower unit 332, and the rotation axis 332d of the impeller 332c are approximately aligned. This suppresses air pressure loss and allows the suction unit to be made smaller.

[0035] As described above, the cross-sectional shape of exhaust port 331b of blower unit 331 is rectangular, and the cross-sectional shape of intake port 332a of blower unit 332 is circular.

[0036] As described above, the cross-sectional shape of intake port 331a of blower unit 331 is circular, and the cross-sectional shape of exhaust port 331b of blower unit 331 is rectangular.

[0037] As described above, the cross-sectional shape of intake port 332a of blower unit 332 is circular, and the cross-sectional shape of exhaust port 332b of blower unit 332 is rectangular.

[0038] As a result, for example, it becomes possible to use an inexpensive centrifugal fan in the blower unit, thereby reducing the cost of the suction unit.

[0039] <Feeding device> Next, the configuration of a feed device equipped with the above-mentioned suction unit will be described.

[0040] FIG. 5 is a schematic configuration diagram illustrating an example of a feed device according to an embodiment.

[0041] The feed device 300 includes, for example, a suction unit 330 and a feed section 310. In this example, the suction unit 330 is used in combination with the intake port conversion unit (intermediate duct 335, chamber 336) shown in Fig. 1(b). The intake port of the chamber 336 is provided on the bottom surface of the chamber 336, and the chamber 336 takes in air in the Z direction in the figure when the blower unit 331 is driven.

[0042] The feed section 310 includes, for example, a drive roller 310a, a driven roller 310b, and an endless belt 310c stretched around the drive roller 310a and the driven roller 310b. A chamber 336 is provided in the space between the drive roller 310a and the driven roller 310b inside the endless belt 310c. The endless belt 310c has through holes in a part or the entire surface of the belt that can communicate with the suction port of the chamber 336. In addition, sheets S, which are an example of a medium, are stacked below the endless belt surface on the side facing the suction port of the chamber 336.

[0043] In the above configuration, when the suction operation by the suction unit 330 is started, the uppermost sheet from the stacked sheets S is sucked onto the belt surface of the endless belt 310c by the suction in the Z direction of the chamber 336. The endless belt 310c that has sucked the sheet rotates in the same direction as the driving roller 310a is rotated in the arrow direction, and sends the sheet in the X direction. Here, the chamber 336 is an example of a "suction section."

[0044] The feed unit 310 is not limited to the above configuration. For example, the chamber 336 may be a cylindrical chamber, and the endless belt 310c may be replaced with a cylindrical member that can contain the cylindrical chamber, and the cylindrical member may be rotated outside the cylindrical chamber. This allows the feed unit 310 to be made smaller.

[0045] In addition, the exhaust port 332b of the blower unit 332 is provided facing the positive side in the Y direction, that is, the side where the sheets S are not placed, so that the air exhausted from the exhaust port 332b does not hit the stacked sheets S. In particular, when the sheets S are heavy sheets such as thick paper or large-sized paper, it is necessary to increase the suction force to suck the top sheet into the endless belt 310c. As a result of the generation of a large suction force, the air pressure exhausted from the exhaust port 332b also increases, so if this air hits the stacked sheets S, the posture of the sheets S may be disturbed, and the sheets S may not be sent out in the correct posture.

[0046] As in this embodiment, by opening the exhaust port 332b of the blower unit 332 in a direction different from the intake port 331a of the blower unit 331, the air discharged from the exhaust port 332b does not hit the sheets S. Specifically, the exhaust port 332b is provided so as to open in a direction (Y direction in this example) perpendicular to the feed direction (X direction in this example) of the sheets S by the feed section 310. In this case, it is more preferable that the exhaust port 332b is installed so as to discharge the air discharged from the exhaust port 332b to the outside of the feed device 300. This prevents the posture of the stacked sheets S from being disturbed, and the sheets S can be fed in the correct posture.

[0047] As described above, this embodiment is a feeding device 300 having a chamber 336 that sucks in the top sheet from a stack of sheets S, and a feeding section 310 that feeds the sucked sheet in a predetermined direction, and the chamber 336 is connected to the above-mentioned suction unit 330.

[0048] As described above, the intake port 331a of the blower unit 331 is connected to the chamber 336, the exhaust port 331b of the blower unit 331 is connected to the intake port 332a of the blower unit 332 via the duct 333, and the exhaust port 332b of the blower unit 332 opens in a different direction from the intake port 331a of the blower unit 331.

[0049] As described above, the exhaust port 332b of the blower unit 332 opens in a direction perpendicular to the feeding direction of the sheet S by the feed section 310.

[0050] This reduces disturbance of the posture of the stacked sheets caused by the air discharged from the exhaust port, and allows the sheets to be sent out in the correct posture.

[0051] As described above, the exhaust port 332b of the blower unit 332 exhausts the air to the outside of the blower device 300.

[0052] This prevents the air exhausted from the exhaust port from disturbing the posture of the stacked sheets, allowing the sheets to be fed out in a more correct posture.

[0053] The material of the sheet S shown as an example of the medium is not limited to paper, but may be, for example, plastic, fiber, leather, metal, glass, wood, ceramics, or a current collector such as aluminum foil or copper foil.

[0054] <Configuration of Image Forming Apparatus> 6 is a schematic diagram showing an example of an image forming apparatus according to an embodiment of the present invention, which is a printer that forms images by an electrophotographic method.

[0055] The printer 1000 includes an image creating unit 1, a transfer unit 2, a sheet supply unit 3, a fixing unit 4, a sheet returning unit 5, a sheet discharging unit 6, and an exposure unit 7. Here, the image creating unit 1, the transfer unit 2, and the exposure unit 7 are examples of an "image forming means."

[0056] The imaging section 1 includes a plurality of imaging units 10A, 10B, 10C, and 10D. The imaging units 10A to 10D have the same or equivalent configurations, and are therefore collectively referred to as imaging unit 10 unless otherwise distinguished.

[0057] The imaging units 10A to 10D form toner images of different colors. For example, the imaging unit 10A forms a yellow (Y) toner image, the imaging unit 10B forms a magenta (M) toner image, the imaging unit 10C forms a cyan (C) toner image, and the imaging unit 10D forms a black (K) toner image.

[0058] The number of imaging units 10 and the order of the colors are not limited to those described above. The number of imaging units 10 may be three or less, or five or more. The order of the colors of the imaging units 10 may be determined appropriately depending on the specifications of the imaging units and the toner characteristics. The imaging section 1 may also include imaging units that use toner of special colors other than Y, M, C, and K. The special colors are not necessarily limited to colored colors, and may include colorless colors such as clear toner.

[0059] The imaging unit 10 includes a photoconductor 11, a charging roller 12, a developing roller 13, and a cleaner 14. The photoconductor 11 is, for example, a cylindrical photoconductor drum. The photoconductor 11 is driven to rotate in a clockwise direction (indicated by an arrow) in the drawing. The charging roller 12 applies an electric charge to the surface of the photoconductor 11, thereby charging the surface of the photoconductor 11 to a predetermined potential.

[0060] The developing roller 13 carries a two-component developer containing, for example, toner and a magnetic carrier on its surface. The developing roller 13 applies toner to an electrostatic latent image formed by exposing the surface of the photoreceptor 11, which is charged to a predetermined potential, by an exposure unit 7 described below, thereby forming a toner image on the surface of the photoreceptor 11. The cleaner 14 includes a cleaning member such as a cleaning roller or a cleaning blade. The cleaner 14 cleans the surface of the photoreceptor 11 that has passed through a transfer unit 2 described below.

[0061] The transfer section 2 is disposed, for example, below the imaging section 1. The transfer section 2 includes a plurality of transfer rollers 20, a transfer belt 21, and the like. The transfer rollers 20 are provided at positions facing the photoconductor 11 provided in the imaging unit 10. The transfer rollers 20 are provided so as to be able to come into contact with the photoconductor 11 via the transfer belt 21, and a nip (hereinafter referred to as a transfer nip) is formed between the photoconductor 11 and the transfer belt 21 by pressing the transfer roller 20 against the photoconductor 11. A transfer bias is applied to the transfer roller 20, and an electric field is formed in the transfer nip.

[0062] The transfer belt 21 is an endless belt made of a single layer or multiple layers of materials such as vinylidene fluoride, ethylene-tetrafluoroethylene copolymer, polyimide, polycarbonate, etc. The transfer belt 21 is stretched around multiple support rollers and moves in a counterclockwise direction in the drawing.

[0063] The sheet supply unit 3 is disposed, for example, at the bottom of the printer 1000. The sheet supply unit 3 includes a tray 30 for stacking sheets S, which are an example of a medium, and a sending mechanism 31 for sending out the sheets S one by one from the tray 30. The sheet supply unit 3 also includes a synchronous roller pair 33 for transporting the sheets S to the transfer unit 2 at a predetermined timing, and a transport roller 32 for transporting the sheets S sent from the sending mechanism 31 to the synchronous roller pair 33.

[0064] Of these, the delivery mechanism 31 includes a chamber 336 that sucks the topmost sheet S from among the sheets S stacked on the tray 30, a feed section 310 that feeds the sucked sheet S in a predetermined direction, and a delivery section 320 that pays out the sheet S fed from the feed section 310 to the transport rollers 32. Here, the chamber 336 is an example of a "suction section."

[0065] The fixing unit 4 is disposed, for example, downstream of the transfer unit 2 in the sheet conveying direction. The fixing unit 4 includes a heating roller 40 and a pressure roller 41. The heating roller 40 and the pressure roller 41 can come into contact with each other, and form a nip (hereinafter, referred to as a fixing nip) by coming into contact with each other. The sheet S, onto which the toner image has been transferred in the transfer unit 2, is heated and pressurized in the fixing nip, and the toner image is fixed to the sheet S.

[0066] The sheet discharge section 6 is disposed, for example, downstream in the sheet conveying direction with respect to the fixing section 4. The sheet discharge section 6 includes switching mechanisms 60a, 60b that switch the discharge destination of the sheet S, and conveys the sheet S to the outside of the apparatus or toward the sheet return section 5 described later by the switching mechanisms 60a, 60b.

[0067] The sheet return unit 5 is disposed, for example, below the sheet discharge unit 6, the fixing unit 4, and the transfer unit 2. The sheet return unit 5 includes a return path 50 provided with a plurality of transport rollers. The end point of the return path 50 merges with the sheet supply unit 3, and the sheet S sent from the sheet discharge unit 6 is transported again toward the transfer unit 2.

[0068] The exposure unit 7 is disposed, for example, above the imaging unit 1. The exposure unit 7 scans the photoconductor 11, which has been charged to a predetermined potential by the charging roller 12, with laser light L to form an electrostatic latent image on the surface of the photoconductor 11.

[0069] In the above configuration, when the printer 1000 receives image data from an external computer or the like, it transitions to a print job and starts driving the transfer belt 21, etc. Then, in the image forming unit 1, the charging roller 12 uniformly charges the surface of the photoconductor 11, which is rotated, to a predetermined charging potential.

[0070] An electrostatic latent image for each color is formed on the charged surface of the photoreceptor 11 by optical scanning using a laser beam emitted by the exposure unit 7 based on image data. The electrostatic latent images are developed into toner images by the development roller 13, and then transferred in order to the surface of the sheet S transported by the transfer belt 21, becoming a toner image in which the colors are superimposed. After the toner image is transferred to the sheet S, the photoreceptor 11 is cleaned by the cleaner 14, and the toner and the like remaining on the surface of the photoreceptor 11 are removed from the surface of the photoreceptor 11.

[0071] The sheet S sent out from the delivery mechanism 31 of the sheet supply unit 3 is transported until it hits the synchronous roller pair 33, and when the sheet S hits the synchronous roller pair 33, the transport is temporarily stopped. Then, the synchronous roller pair 33 resumes transport in time with the toner image on the photoconductor 11 reaching the transfer nip. A toner image is transferred to the sheet S, whose transport has been resumed from the synchronous roller pair 33, in synchronization with the toner image on the photoconductor 11 at the transfer nip.

[0072] After the transfer, the sheet S moves to the fixing section 4, which applies heat and pressure to the toner image on the sheet S to fix the toner image to the sheet S. The sheet S then moves to the sheet discharge section 6, and is sent to the outside of the machine or to the sheet return section 5 according to the guidance of switching mechanisms 60a and 60b. The sheet return section 5 is primarily used when the sheet S is turned upside down (front and back) and sent again to the transfer nip, and the sheet S is discharged from the sheet discharge section 6 after the toner image is transferred to the back side of the sheet S in the transfer nip.

[0073] In the printer 1000 having the above configuration, for example, the above-mentioned feeding device 300 can be applied as the chamber 336 and the feeding section 310 of the sending mechanism 31. This allows the sheet S to be supplied to the imaging section 1 in a correct posture, thereby improving the operational reliability of the printer 1000.

[0074] The image forming apparatus is not limited to a printer that forms an image by an electrophotographic method, but may be a printer that forms an image by another method, such as an inkjet method.

[0075] What has been described above is one example, and other embodiments, additions, modifications, deletions, and other changes can be made within the scope of what a person skilled in the art can imagine. As long as the effects of the present invention are achieved in any of the following aspects, they are included in the scope of the present invention.

[0076] [Aspect 1] Aspect 1 comprises a first blowing means (e.g., blower unit 331) having an intake port and an exhaust port, a second blowing means (e.g., blower unit 332) having an intake port and an exhaust port, and an air guide member (e.g., duct 333) connecting the exhaust port of the first blowing means and the intake port of the second blowing means, wherein the exhaust port (e.g., exhaust port 331b) of the first blowing means and the intake port (e.g., intake port 332a) of the second blowing means have different cross-sectional areas, and the air guide member is formed by gradually changing the ridge line connecting the exhaust port of the first blowing means and the intake port of the second blowing means.

[0077] [Aspect 2] A second aspect of the present invention is characterized in that in the first aspect, the exhaust port of the first blowing means and the intake port of the second blowing means have different cross-sectional shapes.

[0078] [Aspect 3] Aspect 3 is characterized in that, in aspect 1 or aspect 2, the second blowing means is provided with a rotatable impeller (e.g., impeller 332c), and when the impeller is viewed in a plane, the positions of the cross-sectional center of the exhaust port (e.g., exhaust port 331b) of the first blowing means, the cross-sectional center of the intake port (e.g., intake port 332a) of the second blowing means, and the rotation axis of the impeller (e.g., rotation axis 332d) are approximately aligned.

[0079] [Aspect 4] Aspect 4 is characterized in that in any one of Aspects 1 to 3, the cross-sectional shape of the exhaust port (e.g., exhaust port 331b) of the first blowing means is rectangular, and the cross-sectional shape of the intake port (e.g., intake port 332a) of the second blowing means is circular.

[0080] [Aspect 5] Aspect 5 is characterized in that in any one of aspects 1 to 4, the cross-sectional shape of the intake port (e.g., intake port 331a) of the first blowing means is circular, and the cross-sectional shape of the exhaust port (e.g., exhaust port 331b) of the first blowing means is rectangular.

[0081] [Aspect 6] Aspect 6 is characterized in that in any one of aspects 1 to 5, the cross-sectional shape of the intake port (e.g., intake port 332a) of the second blowing means is circular, and the cross-sectional shape of the exhaust port (e.g., exhaust port 332b) of the second blowing means is rectangular.

[0082] [Aspect 7] Aspect 7 is a feeding device having a suction section (e.g., chamber 336) that sucks the topmost medium from stacked media (e.g., sheets S) and a feed section (e.g., feed section 310) that feeds the sucked medium in a predetermined direction, characterized in that the suction section is connected to a suction unit (e.g., suction unit 330) of any of aspects 1 to 6.

[0083] [Aspect 8] Aspect 8 is characterized in that, in aspect 7, the air intake (e.g., air intake 331a) of the first air blowing means is connected to the suction section (e.g., chamber 336), the exhaust port (e.g., exhaust port 331b) of the first air blowing means is connected to the air intake (e.g., air intake 332a) of the second air blowing means via the air guide member (e.g., duct 333), and the exhaust port (e.g., exhaust port 332b) of the second air blowing means opens in a direction different from the air intake of the first air blowing means.

[0084] [Aspect 9] Aspect 9 is characterized in that, in aspect 8, the exhaust port (e.g., exhaust port 332b) of the second blowing means opens in a direction (e.g., Y direction in Figure 5) perpendicular to the feeding direction (e.g., X direction in Figure 5) of the medium by the feeding section (e.g., feeding section 310).

[0085] [Aspect 10] Aspect 10 is characterized in that in any of aspects 7 to 9, the exhaust port (e.g., exhaust port 332b) of the second blowing means discharges air to the outside of the feeding device (e.g., feeding device 300).

[0086] [Aspect 11] Aspect 11 is an image forming apparatus (e.g., printer 1000) characterized by comprising an image forming means (e.g., image creating unit 1, transfer unit 2, exposure unit 7) that forms an image on a medium (e.g., sheet S), and a feed device (e.g., feed device 300) of any of aspects 7 to 10 that feeds the medium toward the image forming means. [Explanation of symbols]

[0087] 300 Feeder 310 Feeding section 310a Drive roller 310b driven roller 310c endless belt 330 Suction Unit 331 Blower unit (first blower means) 331a Air intake 331b Exhaust port 331c Impeller 331d Rotation axis 332 Blower unit (second blower means) 332a Air intake 332b Exhaust port 332c Impeller 332d Rotation axis 333 Duct (wind guide member) 333a First opening 333b Second opening 334 Intake conversion unit 335 Intermediate Duct 336 Chamber (suction part)

Claims

1. A first blowing means having an intake port and an exhaust port; A second blowing means having an intake port and an exhaust port; a wind guide member connecting the exhaust port of the first blowing means and the intake port of the second blowing means, The exhaust port of the first blowing means and the intake port of the second blowing means have different cross-sectional areas, The suction unit according to claim 1, wherein the air guide member is formed by gradually changing a ridge line connecting the exhaust port of the first air blowing means and the intake port of the second air blowing means.

2. 2. The suction unit according to claim 1, wherein the exhaust port of the first blowing means and the intake port of the second blowing means have different cross-sectional shapes.

3. 2. The suction unit according to claim 1, characterized in that the second blowing means includes a rotatable impeller, and when the impeller is viewed in a plan view, the positions of the cross-sectional center of the exhaust port of the first blowing means, the cross-sectional center of the intake port of the second blowing means, and the rotation axis of the impeller are substantially aligned.

4. 3. The suction unit according to claim 2, wherein the cross-sectional shape of the exhaust port of the first blowing means is rectangular, and the cross-sectional shape of the intake port of the second blowing means is circular.

5. 3. The suction unit according to claim 2, wherein the cross-sectional shape of the intake port of the first blowing means is circular, and the cross-sectional shape of the exhaust port of the first blowing means is rectangular.

6. 3. The suction unit according to claim 2, wherein the cross-sectional shape of the intake port of the second blowing means is circular, and the cross-sectional shape of the exhaust port of the second blowing means is rectangular.

7. a suction section for suctioning the topmost medium from the stack of media; a feeding unit that feeds the sucked medium in a predetermined direction, A feeding device, comprising: a suction unit according to claim 1 connected to the suction section.

8. The air intake of the first blowing means is connected to the suction section, the exhaust port of the first blower means is connected to the intake port of the second blower means via the air guide member, 8. The feeding device according to claim 7, wherein the exhaust port of the second blowing means opens in a different direction from the intake port of the first blowing means.

9. 9. The feeding device according to claim 8, wherein the exhaust port of the second blowing means is open in a direction perpendicular to a feeding direction of the medium by the feeding section.

10. 8. The feeding device according to claim 7, wherein the exhaust port of the second blowing means exhausts air to the outside of the feeding device.

11. An image forming means for forming an image on a medium; a feeding device according to claim 7 for feeding the medium towards the image forming means; An image forming apparatus comprising:

Images