Document transport device, image forming apparatus

Abstract

To provide a document transport device and an image forming apparatus that can prevent documents from falling out of the tray without deforming the documents. [Solution] The ADF comprises a mounting tray 14 on which a document is placed and an output tray 13 on which the document is ejected. The mounting tray 14 is supported so as to be movable between a contact position in contact with the output tray 13 and a separation position away from the output tray 13. The ADF comprises a torsion coil spring 42 that biases the mounting tray 14 toward the output tray 13, and a contact portion 35 that protrudes from the mounting tray 14 toward the output tray 13 and contacts the document table when the ADF is closed, separating the mounting tray 14 from the output tray 13.

Description

Technical Field

[0006] , ,

[0005] , ,

[0001] The present invention relates to a document conveying device and an image forming apparatus.

Background Art

[0002] There is known a document conveying device that is provided so as to be openable and closable with respect to a document table of an image reading device. For example, the document conveying device includes a placement tray on which a document to be conveyed is placed, and a discharge tray that is provided to face the back surface of the placement tray and from which the document is discharged.

[0003] In the document conveying device, when the document conveying device is opened while the document remains on the discharge tray, the document may fall from the discharge tray. In contrast, there is known as a related art a document conveying device provided with a fall prevention member provided on the back surface of the placement tray to prevent the document from falling from the discharge tray (see Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the document conveying device according to the related art, when the document conveying device is opened while the document remains on the discharge tray, the document is supported by the fall prevention member and is curved. Therefore, after the document conveying device is closed, there is a possibility that the shape at the time of bending remains as a habit in the document.

[0006] An object of the present invention is to provide a document conveying device and an image forming apparatus capable of suppressing the document from falling from the tray without deforming the document. [Means for solving the problem]

[0007] A document transport device according to one aspect of the present invention is provided so as to be openable and closable with respect to the document table of an image reader, and comprises a transport unit, a placement tray, and an output tray. The transport unit transports a document whose image is read by the image reader. The placement tray is on which the document transported by the transport unit is placed. The output tray is provided opposite to the placement tray, and the document transported by the transport unit is output. In the document transport device, the first tray, which is located on the upper side of the placement tray and the output tray, is supported so as to be movable between a contact position in contact with the lower second tray and a separation position separated from the second tray. The document transport device also comprises a biasing unit and a contact unit. The biasing unit biases the first tray toward the second tray. The contact unit is provided so as to protrude from the first tray toward the second tray, and when the document transport device is closed, it contacts the document table to separate the first tray from the second tray.

[0008] An image forming apparatus according to another aspect of the present invention comprises the document transport device and the image reading device, and forms an image of the document read by the image reading device onto a sheet. [Effects of the Invention]

[0009] According to the present invention, it is possible to prevent a document from falling out of the tray without deforming the document. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a cross-sectional view showing the configuration of an image forming apparatus according to an embodiment of the present invention. [Figure 2] Figure 2 is a perspective view showing the configuration of the ADF and image reading unit of an image forming apparatus according to an embodiment of the present invention. [Figure 3] Figure 3 is a perspective view showing the configuration of the ADF and image reading unit of an image forming apparatus according to an embodiment of the present invention. [Figure 4] Figure 4 is a perspective view showing the configuration of the ADF and image reading unit of an image forming apparatus according to an embodiment of the present invention. [Figure 5] Figure 5 is a perspective view showing the configuration of the mounting tray of an image forming apparatus according to an embodiment of the present invention. [Figure 6] Figure 6 is a cross-sectional view showing the configuration of the ADF of an image forming apparatus according to an embodiment of the present invention. [Figure 7] Figure 7 is a cross-sectional view showing the configuration of the ADF of an image forming apparatus according to an embodiment of the present invention. [Modes for carrying out the invention]

[0011] The embodiments of the present invention will be described below with reference to the attached drawings. Note that the following embodiments are merely examples of the present invention and do not limit the technical scope of the present invention.

[0012] [Configuration of the image forming apparatus 100] First, the configuration of the image forming apparatus 100 according to an embodiment of the present invention will be described with reference to Figures 1 to 4. Here, Figure 2 is a perspective view of the ADF1 in a closed state relative to the document glass 21, as seen from the rear side of the image forming apparatus 100. Figure 3 is a perspective view of the ADF1 in an open state relative to the document glass 21, as seen from the rear side of the image forming apparatus 100. Figure 4 is a perspective view of the ADF1 in a closed state relative to the document glass 21, as seen from the front side of the image forming apparatus 100.

[0013] For the sake of explanation, the vertical direction is defined as the up-down direction D1 when the image forming apparatus 100 is in a usable installation state (as shown in Figure 1). The front-to-back direction D2 is defined with the front side of the image forming apparatus 100 shown in Figure 1 being the front. The left-to-right direction D3 is defined with the front of the image forming apparatus 100 in the aforementioned installation state as the reference point.

[0014] The image forming apparatus 100 is a multi-functional device having a plurality of functions such as a fax function and a copy function, together with a scan function for reading an image from a document and a print function for forming an image based on image data. Note that the image forming apparatus 100 may be a copy machine.

[0015] As shown in FIG. 1, the image forming apparatus 100 includes an ADF (Auto Document Feeder) 1, an image reading unit 2, an image forming unit 3, and a paper feeding unit 4.

[0016] The image forming unit 3 forms an image on a sheet based on image data. Specifically, the image forming unit 3 forms an image on a sheet by an electrophotographic method. For example, the image forming unit 3 includes a photoreceptor drum, a charging roller, an optical scanning device, a developing device, a transfer roller, a cleaning device, a fixing device, and a sheet discharging unit. Note that the image forming unit 3 may form an image on a sheet by another image forming method such as an inkjet method.

[0017] The paper feeding unit 4 supplies a sheet to the image forming unit 3. The paper feeding unit 4 includes a paper feeding cassette and a plurality of conveyance rollers.

[0018] The image reading unit 2 is capable of reading an image of a document. Specifically, the image reading unit 2 is capable of reading an image of a document by a CCD (Charge Coupled Device) method. As shown in FIG. 1, the image reading unit 2 includes a document table 21, a reading unit 22, a mirror 23, a mirror 24, an optical lens 25, and a CCD 26.

[0019] The document table 21 is the upper surface portion of a box-shaped housing that houses each component of the image reading unit 2. The document table 21 includes a contact glass on which a document is placed.

[0020] The reading unit 22 is provided below the contact glass of the platen 21. The reading unit 22 is configured to be movable along the sub-scanning direction in the same direction as the left-right direction D3 by a moving mechanism (not shown) having a driving unit such as a stepping motor. As shown in FIG. 1, the reading unit 22 includes a light source 22A and a mirror 22B.

[0021] The light source 22A is a plurality of LEDs arranged along the main scanning direction in the same direction as the front-rear direction D2. The light source 22A emits light for one line in the main scanning direction toward the contact glass of the platen 21. The light emitted from the light source 22A passes through the contact glass and irradiates the document placed on the platen 21 or the document conveyed by the ADF 1. The mirror 22B reflects the light emitted from the light source 22A and reflected by the document to the mirror 23.

[0022] The mirror 23 reflects the light reflected by the mirror 22B of the reading unit 22 to the mirror 24. The mirror 24 reflects the light reflected by the mirror 23 to the optical lens 25. The optical lens 25 condenses the light reflected by the mirror 24 and makes it incident on the CCD 26.

[0023] The CCD 26 is an image sensor having a plurality of photoelectric conversion elements arranged along the main scanning direction. The CCD 26 outputs an electrical signal corresponding to the amount of received light. In the image reading unit 2, the light emitted from the light source 22A and reflected by the document is incident on the CCD 26 via the mirror 22B, the mirror 23, the mirror 24, and the optical lens 25. As a result, an analog electrical signal corresponding to the image of the document is output from the CCD 26. The analog electrical signal output from the CCD 26 is converted into a digital electrical signal (image data) by an AFE (analog front end) circuit (not shown) and input to a control unit (not shown). The image data output from the image reading unit 2 is used for forming an image by the image forming unit 3 and the like.

[0024] The image reading unit 2 may also read the image of the document using the CIS (Contact Image Sensor) method.

[0025] The ADF1 transports the document whose image is to be read by the image reading unit 2.

[0026] As shown in Figure 1, the ADF1 is provided above the document tray 21 of the image reading unit 2. The ADF1 is also provided so as to be openable and closable relative to the document tray 21 of the image reading unit 2. Specifically, the ADF1 is supported by a pair of hinges provided at the rear end of the document tray 21 so as to be rotatable in the rotation direction D4 shown in Figure 3. This allows the ADF1 to change its orientation between a closed position that covers the document tray 21 (see Figure 2) and an open position that exposes the document tray 21 (see Figure 3). The ADF1 is an example of the document transport device of the present invention. The image reading unit 2 is also an example of the image reading device of the present invention.

[0027] As shown in Figure 1, the ADF1 comprises a storage section 11, a cover section 12, an output tray 13, a mounting tray 14, a pickup roller 15, a plurality of transport rollers 16, and a rear wall section 17.

[0028] The storage section 11 houses the pickup roller 15 and a plurality of transport rollers 16 used for transporting documents. As shown in Figure 4, the storage section 11 is formed in a roughly rectangular parallelepiped shape, with dimensions in the front-to-back direction D2 being approximately the same as the document table 21, and dimensions in the left-to-right direction D3 being smaller than the document table 21. A document loading port 11A (see Figure 1) is formed on the right side of the storage section 11 into which documents are loaded. Below the document loading port 11A on the right side of the storage section 11, a document discharge port 11B (see Figure 1) is formed into which documents are discharged. Inside the storage section 11, a document transport path 11C (see Figure 1) is formed, leading from the document loading port 11A to the document discharge port 11B.

[0029] As shown in Figure 4, the cover portion 12 is formed as a flat plate extending to the right from the bottom of the right side of the storage portion 11. Together with the bottom surface of the storage portion 11, the cover portion 12 forms a cover surface that covers the document glass 21 of the image reading unit 2. This cover surface is also the bottom surface of the ADF 1. As shown in Figure 4, the storage portion 11 is positioned above the area including the left end of the document glass 21 when the ADF 1 is closed to the document glass 21. Also, as shown in Figure 4, the cover portion 12 is positioned above the area including the right end of the document glass 21 when the ADF 1 is closed to the document glass 21.

[0030] As shown in Figures 1 and 4, the output tray 13 is formed on the upper part of the cover portion 12. Documents transported by the ADF 1 are discharged into the output tray 13.

[0031] As shown in Figures 1 and 4, the loading tray 14 is provided above the output tray 13 and opposite to the output tray 13. The loading tray 14 is provided so as to extend to the right from below the document input port 11A and above the document output port 11B on the right side of the storage section 11. Documents transported by the ADF 1 are placed on the loading tray 14. The loading tray 14 is formed in a flat shape having a loading surface 31 (see Figure 4) on which the documents are placed. The loading tray 14 is positioned so as to be inclined downward toward the document input port 11A so that documents placed on the loading surface 31 are guided toward the document input port 11A. The position of documents placed on the loading surface 31 in the front-to-back direction D2 is adjusted by a pair of side cursors 32 shown in Figure 4.

[0032] The pickup roller 15 contacts the top surface of the uppermost document among the multiple documents placed on the tray 14, and feeds that document onto the document transport path 11C.

[0033] Multiple transport rollers 16 are arranged at intervals from each other along the document transport path 11C. Each transport roller 16 transports the document fed out by the pickup roller 15 in the transport direction D5 (see Figure 1) toward the document output port 11B.

[0034] The pickup roller 15 and the multiple transport rollers 16 transport the document whose image is read by the image reading unit 2. The pickup roller 15 and the multiple transport rollers 16 are an example of the transport unit of the present invention.

[0035] As shown in Figure 4, the rear wall portion 17 is erected along the rear end of the upper surface of the cover portion 12.

[0036] Incidentally, in conventional document transport devices, if the document transport device is opened while a document remains in the output tray 13, the document may fall from the output tray 13 to the back side of the document transport device. In response to this, a document transport device equipped with a fall prevention member provided on the back side of the mounting tray 14 to prevent the document from falling from the output tray 13 is known as a related technology.

[0037] However, in the document transport device relating to the above-mentioned related technology, if the document transport device is opened while a document remains in the output tray 13, the document is supported by the fall prevention member and bends. Therefore, after the document transport device is closed, there is a risk that the bent shape will remain on the document as a permanent deformation.

[0038] In contrast, the image forming apparatus 100 according to an embodiment of the present invention can prevent the document from falling out of the tray without deforming the document, as will be explained below.

[0039] Specifically, in the image forming apparatus 100, if the ADF1 is opened while a document remains in the output tray 13, the document remaining in the output tray 13 is held between the mounting tray 14 and the output tray 13. This prevents the document remaining in the output tray 13 from falling out.

[0040] Furthermore, in the image forming apparatus 100, if the ADF1 is opened while a document remains in the output tray 13, the rear wall 17 prevents the document from falling to the rear side of the image forming apparatus 100.

[0041] [Configuration of mounting tray 14] Next, the configuration of the mounting tray 14 will be described with reference to Figure 5.

[0042] As shown in Figure 5, the mounting tray 14 includes a mounting surface 31 and a pair of side cursors 32, as well as a pair of rotating shafts 33, a pair of pressed parts 34, and a pair of contact parts 35. Note that Figure 5 only shows the rotating shaft 33 on the front side of the image forming apparatus 100 out of the pair of rotating shafts 33. Also, Figure 5 only shows the pressed part 34 on the front side of the image forming apparatus 100 out of the pair of pressed parts 34.

[0043] As shown in Figure 5, the pair of rotating shafts 33 are provided at the downstream end of the mounting tray 14 in the transport direction D5. Each of the rotating shafts 33 is formed in a cylindrical shape that protrudes outward in the front-to-back direction D2 from both sides of the mounting tray 14 in the front-to-back direction D2. The pair of rotating shafts 33 are arranged so that their axes coincide.

[0044] As shown in Figure 5, the pair of press-to-press portions 34 are located upstream of the pair of rotating shafts 33 in the transport direction D5 on the mounting tray 14. Each of the press-to-press portions 34 is formed in the shape of a rectangular prism that protrudes outward in the front-to-back direction D2 from both sides of the mounting tray 14 in the front-to-back direction D2.

[0045] As shown in Figure 5, the pair of contact portions 35 are located upstream of the pair of pressed portions 34 on the mounting tray 14 in the transport direction D5. Each of the contact portions 35 is formed in the shape of a rectangular prism with a thin thickness in the front-to-back direction D2, protruding toward the discharge tray 13 from both sides in the front-to-back direction D2 on the mounting tray 14.

[0046] The mounting tray 14 is supported by the storage section 11 so as to be able to pivot around a pair of rotation axes 33 that are perpendicular to the transport direction D5 and aligned with the width direction (the same direction as the front-rear direction D2), with the downstream end of the document transport direction D5 as the pivot point. The mounting tray 14 is an example of the first tray of the present invention. The discharge tray 13 is an example of the second tray of the present invention.

[0047] The storage section 11 includes a pair of bearing sections 41 that rotatably support a pair of rotating shafts 33 of the mounting tray 14.

[0048] [Configuration around the bearing portion 41] Next, with reference to Figures 6 and 7, the configuration of the front bearing portion 41 in the front-to-back direction D2 and the surrounding area of ​​that bearing portion 41 will be described. Here, Figure 6 is a cross-sectional view showing the configuration of the ADF1 in a closed state relative to the document table 21. In Figure 6, an enlarged view showing the configuration of the surrounding area of ​​the bearing portion 41 is shown by a dashed line. Figure 7 is a cross-sectional view showing the configuration of the ADF1 in an open state relative to the document table 21. In Figure 7, an enlarged view showing the configuration of the surrounding area of ​​the bearing portion 41 is shown by a dashed line. Note that the configuration of the rear bearing portion 41 in the front-to-back direction D2 and the surrounding area of ​​that bearing portion 41 are the same as the configuration of the front bearing portion 41 in the front-to-back direction D2 and the surrounding area of ​​that bearing portion 41, so the explanation will be omitted.

[0049] As shown in Figure 6, the bearing portion 41 is formed in a flat plate shape perpendicular to the front-rear direction D2. The bearing portion 41 has an axial hole through which the rotating shaft 33 of the mounting tray 14 is inserted. The mounting tray 14 is supported so as to be able to swing along the swing direction D6 shown in Figure 6 by the insertion of a pair of rotating shafts 33 into the axial holes of a pair of bearing portions 41.

[0050] As shown in Figure 6, a torsion coil spring 42 and a spring support portion 43 are provided around the bearing portion 41. In other words, the housing portion 11 is equipped with a torsion coil spring 42 and a spring support portion 43.

[0051] The torsion coil spring 42 biases the mounting tray 14 toward the discharge tray 13. The torsion coil spring 42 is provided such that the coil portion wraps around the outer circumference of the rotating shaft 33, which is inserted through the shaft hole of the bearing portion 41. The torsion coil spring 42 is an example of the biasing portion of the present invention.

[0052] The spring support portion 43 is provided on the wall surface of the bearing portion 41 on the side from which the rotating shaft 33 protrudes. The spring support portion 43 supports one end of the torsion coil spring 42. By being supported at one end by the spring support portion 43, the torsion coil spring 42 biases the object to be biased in the biasing direction D7 (see Figure 6) when it comes into contact with the other end.

[0053] As shown in Figure 6, the pressed portion 34 of the mounting tray 14 is positioned to contact the other end of the torsion coil spring 42. As a result, the mounting tray 14 is biased in the biasing direction D7 (see Figure 6) by the torsion coil spring 42.

[0054] As shown in Figure 7, when the ADF 1 is open relative to the document glass 21, the mounting tray 14 is biased in the biasing direction D7 by the torsion coil spring 42 and comes into contact with the output tray 13 (see the area enclosed by the dashed line in Figure 7). As a result, any documents remaining in the output tray 13 are held between the mounting tray 14 and the output tray 13. An elastic member such as a sponge sheet may be provided on the back surface of the mounting tray 14 (the surface on the back of the mounting surface 31) to increase the contact area with the document.

[0055] As shown in Figure 7, the pair of contact portions 35 are provided so as to protrude from the bottom surface of the ADF1 in the biasing direction D7 when the ADF1 is open to the document tray 21.

[0056] The pair of contact parts 35 contact the document glass 21 when the ADF 1 is closed against the document glass 21, causing the mounting tray 14 to move away from the output tray 13. Specifically, when the ADF 1 is closed against the document glass 21, the pair of contact parts 35 contact the document glass 21 before the bottom surface of the ADF 1 contacts the document glass 21. As a result, the mounting tray 14 is pressed by the document glass 21 in the opposite direction to the biasing direction D7 and rotates in the opposite direction to the biasing direction D7. Therefore, as shown in Figure 6, the mounting tray 14 moves away from the output tray 13 (see the area enclosed by the dashed line in Figure 6).

[0057] Thus, in the ADF1, the mounting tray 14 is supported so as to be movable between a contact position where it is in contact with the output tray 13 (see Figure 7) and a separation position where it is separated from the output tray 13 (see Figure 6). Specifically, the mounting tray 14 is supported so as to be able to swing around a pair of rotation axes 33, with its downstream end in the transport direction D5 as the pivot point. This makes it possible to hold the document remaining in the output tray 13 between the mounting tray 14 and the output tray 13. Therefore, it is possible to prevent the document from falling from the tray without deforming the document.

[0058] [Differentiation] The mounting tray 14 may be supported so as to be movable in a direction perpendicular to the bottom surface of the ADF 1. Specifically, the mounting tray 14 may be supported by the storage section 11 so as to be movable along a direction perpendicular to the bottom surface of the ADF 1.

[0059] Furthermore, the first tray of the present invention may also be a discharge tray 13. That is, the mounting tray 14 may be formed on the upper part of the cover portion 12. Also, the discharge tray 13 may be provided above the mounting tray 14, facing the mounting tray 14.

[0060] [Notes on the invention] The following is an overview of the invention extracted from the above-described embodiments. Note that each configuration and processing function described below can be selected and combined as desired.

[0061] <Note 1> A document transport device that is openably and closably mounted on the document tray of an image reading device, comprising: a transport unit for transporting a document whose image is read by the image reading device; a placement tray on which the document transported by the transport unit is placed; and a discharge tray provided opposite to the placement tray for discharging the document transported by the transport unit, wherein the upper of the placement tray and the discharge tray is supported so as to be movable between a contact position in contact with the lower second tray and a separation position separated from the second tray, and the document transport device comprises: a biasing unit for biasing the first tray toward the second tray side; and a contact unit provided protruding from the first tray toward the second tray side, which contacts the document tray when the document transport device is closed to separate the first tray from the second tray.

[0062] <Note 2> The document transport device according to Appendix 1, wherein the first tray is supported so as to be able to swing about an axis perpendicular to the transport direction, with the downstream end of the tray in the transport direction of the document by the transport unit as the pivot point.

[0063] <Note 3> An image forming apparatus comprising a document transport device as described in Appendix 1 or 2, and the image reading device, wherein the image of the document read by the image reading device is formed on a sheet. [Explanation of symbols]

[0064] 1 ADF 2 Image reading unit 3 Image forming unit 4 Paper feed section 11. Storage Unit 12 Cover section 13. Discharge tray 14 Mounting tray 15 Pickup Roller 16 Conveyor rollers 17 Rear wall 21 Manuscript stand 22 Reading Units 23 Miller 24 Mirror 25 Optical Lenses 26 CCD 31 Mounting surface 32 Side cursor 33 Rotation axis 34 Pressed part 35 Contact area 41 Bearing section 42 Torsion coil spring 43 Spring support section 100 Image forming apparatus

Claims

1. A document transport device that is installed so as to be openable and closable relative to the document tray of an image reading device, A transport unit that transports the original document from which the image is read by the image reading device, A tray on which the document being transported by the transport unit is placed, An output tray is provided opposite the aforementioned mounting tray, and the documents transported by the transport unit are discharged from this output tray, Equipped with, The first tray, located on the upper side of the mounting tray and the discharge tray, is supported so as to be movable between a contact position in contact with the lower second tray and a separated position away from the second tray. The aforementioned document transport device, A biasing unit that biases the first tray toward the second tray, A contact portion is provided that protrudes from the first tray toward the second tray, and when the document transport device is closed, it contacts the document table to separate the first tray from the second tray, A document transport device equipped with the following features.

2. The first tray is supported so as to be able to swing around an axis perpendicular to the transport direction, with the downstream end of the tray in the transport direction of the document by the transport unit as the pivot point. The document transport device according to claim 1.

3. A document transport device according to claim 1 or 2, The aforementioned image reading device, Equipped with, The image of the original document read by the image reading device is formed on a sheet. Image forming apparatus.

Images