JP3906839B2 - Automatic document feeder - Google Patents

Description

  The present invention relates to an image reading apparatus having an ADF (automatic document feeder) function, and in particular, an image configured such that image information on a first surface (front surface) and a second surface (back surface) can be continuously scanned by ADF. The present invention relates to a reading device.

2. Description of the Related Art Conventionally, in an image forming apparatus such as a copying machine or a multifunction machine combining a facsimile machine and a copying machine function, an FBS (Flatbed Scanner) provided with a large-size platen for placing and reading a document of a book is read. In addition to the above, a sheet-through type ADF that reads an image while conveying a sheet original is provided. In the ADF, after reading the first surface of the double-sided document, the image is reversely conveyed through the switchback type conveyance path, and the image on the second surface of the document is read while the document is reversed and returned. It is carried out. It has also been proposed that when the second surface is read, the sheet alignment operation can be satisfactorily performed so that the document to be switched back is not obliquely fed (see, for example, Patent Document 1). ).
Japanese Patent Laid-Open No. 11-263539

  However, the reverse roller mechanism is arranged on the upper part of the ADF even when using a mechanism for switching back the document on which the first surface has been read and feeding it toward the second surface. The combination of the sheet conveyance paths leading to the reversing unit is complicated. In addition, since the document discharge mode cannot be selected from the configuration of the document transport path, there are still issues that need to be solved, such as being unable to cope with various user requests such as page alignment and reverse discharge. There is a need to obtain an automatic document feeder that can set a document conveyance mode that is easier to use.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus that can read a double-sided original in page order and that can improve the handling of the original without disturbing the pages of the discharged double-sided original.

The present invention is provided in a reading device as an image information input unit of an image forming apparatus, and automatically feeds a document set on a document tray one by one toward a reading unit and reads an image of a moving document. About. According to the first aspect of the present invention, the document transported from the document tray on which the document is set is guided to the reversing unit, and the first conveyance path for reading the image of the document through the reading unit, and the lower part of the document tray A document fed in a switchback form from the reversing unit can be guided, a second conveyance path that merges with the first conveyance path, and a document from the first conveyance path to the reversing unit. The first gate for guiding the document returned from the reversing unit to the second transport path, and the document guided on the first transport path to the discharge tray provided above the document tray and the reverse A second gate for branching to the document side, and a third transport path for guiding the document to the discharge tray via the second gate. When reading a double-sided document, the document is fed from the document tray. , The first side of the double-sided document sent to the reversing unit is read via the first transport path and the first gate, and then reversed by the reversing unit, and the first gate and the second transport A second side of the double-sided document sent to the reversing unit via the path and the first conveying path, and then reversed by the reversing unit, the first gate, the second conveying path, the first The sheet is discharged to the discharge tray through one transfer path, the second gate, and the third transfer path .

  According to a second aspect of the present invention, the document reversing portion is configured as a single-sided document discharge tray, and is provided as a member having a function of a platen document pressing plate corresponding to a flatbed scanner.

  According to a third aspect of the present invention, in the automatic document feeder, an uppermost discharge tray, an intermediate document tray, and a lowermost reversing tray are arranged so as to overlap each other, and the original tray and the reversing tray are arranged. Are connected via the first and second conveying paths, and the reverse tray and the discharge tray are provided via the third conveying path.

  With the above-described configuration, once a double-sided original sheet is set on the original tray, the images on the first and second sides are read continuously, and the pages are aligned on the uppermost output tray. Can be discharged in a wet state. Therefore, after reading the images on both sides, the original is not disturbed, post-processing can be easily performed, and the burden on the operator can be reduced. In addition, the double-sided document being reversed is relayed by the reverse tray placed under the discharge tray and is reversed while being nipped by the reverse roller. Can be prevented.

  The automatic document feeder described below can be provided in combination with an image forming apparatus having an arbitrary configuration, and can be operated particularly effectively when a duplex copy is made using a duplex document. It becomes. In addition to the large-sized double-sided copying machine that is generally used as a conventional image forming apparatus that can make a double-sided copy, a duplex-compatible module is attached to a small-sized image forming apparatus. It is also possible to provide a small apparatus.

  The configuration of the apparatus of the present invention will be described according to the illustrated example. In the explanatory view of the image forming apparatus 1 shown in FIG. 1, an image forming apparatus 2 configured integrally by combining an automatic document feeder 40 is configured as an apparatus capable of creating recording paper using an electrophotographic method. The apparatus main body 2 of the image forming apparatus 1 is provided with a paper feed tray 3 at the lowermost part thereof so that paper can be fed by a paper feed roller 4 toward a recording unit. In addition, a sheet feeding device capable of mounting one or a plurality of sheet feeding trays or the like can be separately combined in the lower part of the apparatus main body 2, and the operator can store different size sheets in the sheet feeding unit. It is also possible to easily respond to the request.

  Corresponding to the sheet conveyance path 7 arranged on one side of the apparatus main body 2, a recording unit 10 is provided above the sheet feeding unit, and a toner image is recorded on the sheet by the recording unit 10 Is fixed through the fixing device 18 provided on the upper portion thereof, and the produced recording paper is discharged through the discharge path 20 to the discharge tray 22 by the discharge roller device 21. Below the recording unit 10, a sheet aligning device is provided that aligns the sheet fed from the sheet feeding tray 3 by the sheet feeding roller 4 at the position of the merging unit in the sheet conveying path. In the sheet aligning device, the leading end of the sheet is inserted into the nip portion of the registration roller device 6 and an additional feeding action is applied by the sheet feeding roller to form a loop on the sheet. It is provided so as to perform an alignment action by pressing against the nip portion. In the recording unit 10, the registration roller device 6 is driven to synchronize with the toner image formed on the photosensitive drum 11, and the sheet is fed out. The sheet is conveyed in an obliquely fed state in the recording unit. Control so that it is not.

  The recording unit 10 is provided with a charging unit 12, a writing unit 13, a developing device 16, a transfer unit 14, a cleaner 15, and the like around the photosensitive drum 11 according to a predetermined arrangement relationship. For the photosensitive drum 11 disposed in the recording unit 10, the surface of the photosensitive drum 11 is uniformly charged by the discharge from the corotron 12 as a charging unit, and then the information of the light scanned by the original is scanned. Is applied from the writing device 13 to form an electrostatic latent image on the surface of the photosensitive drum. Then, toner is supplied from the developing roller 17 of the developing device 16 to the electrostatic latent image to make a visible image as a toner image. At a position where the toner image is transferred onto the paper, a predetermined value of voltage is applied to the transfer roller while conveying the paper so as to be sandwiched between the photosensitive drum and the transfer roller 14, thereby The transfer to the sheet is performed in the same manner as in the case of an image forming apparatus using a conventional general electrophotographic system.

  The sheet on which the toner image has been transferred is sent to a fixing device 18 at a downstream portion thereof to be fixed. In the fixing device 18, the interior of the frame is similar to a conventionally known heat roller type fixing device. The heating roller 19 and the pressure roller 19a are arranged in the front, and a predetermined nip pressure is set between the two rollers. Then, toner is melted by the heat of the heat roller 19 with respect to the paper passing through the fixing device 18, and the melted toner is pressed by the pressure roller 19a from the back of the paper to be fixed on the paper. ing. The paper fixed as described above is sent out to the discharge tray 22 by the discharge roller device 21 through the discharge path 20, and when the plurality of recording papers are continuously discharged, the image surface is directed downward. It is piled up sequentially in the state to face. In addition, when the apparatus main body 2 is configured as a single-sided recording apparatus, the discharge roller device 21 is configured to be driven only in one side. A drive device that enables forward and reverse rotation is provided.

  As described above, when the apparatus main body 2 is configured as an apparatus capable of duplex recording, the discharge roller device 21 is configured to be connected to a driving device (not shown) so as to be able to rotate forward and reverse. The In that case, the single-sided recording paper is returned to the paper feed unit through the reverse conveyance path, and an operation is performed in which an image is recorded on the back side of the single-sided copying paper to create a double-sided copy. In order to configure the apparatus capable of duplex copying, an optional reversing conveyance unit 30 is mounted on one side (right side of the drawing) of the apparatus body 2 as auxiliary means (sheet reversing conveyance mechanism) for double-sided recording. It is configured as possible. When the reverse conveyance unit 30 as the optional unit is attached to form an apparatus capable of double-sided recording, the unit frame 31 is attached to the side of the apparatus main body 2.

  Note that any attachment means can be used to attach the main body frame 31 to the reverse conveyance unit 30, and a space for accommodating the manual feed tray 25 on the exposed surface side of the frame. Can be provided. Further, the reverse conveyance unit 30 is supported by the apparatus main body 2 via a support shaft 32 so that the outer portion of the frame 31 can be opened and closed. When the reverse conveyance unit 30 is provided, a discharge roller device is provided at the end of the discharge path 20 of the apparatus main body in order to send the single-side recorded paper from the discharge path 20 of the apparatus main body toward the reverse conveyance path 33. 21 is a forward / reverse conveying roller, and a branching claw member (gate) 23 is provided so as to be swingable about a support shaft 23 a so as to guide the one-side recorded paper toward the reverse path 33.

  The reversal conveyance unit 30 is provided with one or a plurality of conveyance roller devices 34 in the reversal conveyance path 33, and feeds the paper from the reversal path 33 toward the aligning portion of the apparatus main body 2 and is fed from the paper feed tray. As with the incoming paper, the registration roller device 6 positions the leading edge of the paper and then feeds it toward the back side recording. Further, when a paper jam occurs at the position of the reversing path 33, it is possible to easily perform the jam processing by opening the module outside the unit through the support shaft 32. In addition, when the reverse conveyance unit 30 is opened, the outer guide means can be opened and closed in combination with the unit 30 so that the outer guide means of the sheet conveyance path 7 can be removed together. The jam processing in the paper transport path 7 can be performed from one side of the apparatus main body.

  In addition, in the state where the reverse conveyance unit 30 is attached, the manual feed tray 25 is provided so that it can be folded and leaned along the lower part of the unit. The manual feed tray 25 is provided with a second tray member 27 at the front end portion of a tray body 26 supported so as to be swingable with respect to the apparatus body via a support shaft 28 by using hinge means. The second tray member 27 can be used in accordance with the paper size to be set. Then, the paper set in the manual feed tray is sent out by the paper feed roller 29, and below the paper feed path 7 in the main body, the paper feed tray 3, the reverse conveyance path 33, and the paper feed path from the manual feed tray Are merged, aligned by the registration roller device 6, and sent to the recording unit.

  An image reading device 40 is provided on the upper portion of the apparatus main body 2, and a scanning device 45 is provided inside the frame 42 of the reading device 41 so as to be movable in the left-right direction in the drawing. A large platen 43 corresponding to a flat bed scanner (FBS) and a small platen 44 corresponding to an automatic document feeder (ADF) are provided on the upper portion of the frame 42 of the reading device 41. For a book document set on the platen 43, the scanning device 45 is moved along the lower surface of the platen 43 and moved at a predetermined speed by a distance corresponding to the document size in the sub-scanning direction of the document. The reading operation is performed. Further, when reading using the ADF function, the document transported in the document transport path of the ADF 50 is read while the scanning device 45 is stopped at the position of the small platen 44.

  The scanning device 45 provided so as to be movable within the frame 42 of the reading device 41 uses a driving mechanism (not shown) to read a document set on the platen 43 using the FBS function. It is provided so that reciprocation is possible. The scanning device 45 is provided with a lamp 46 at the top of its moving frame, and a plurality of mirrors 47... Are combined in the frame so as to reflect light at a predetermined angle. The length of the reflected optical path is configured to be a predetermined length. Then, the light reflected by the multiple mirrors 47... Is imaged through a lens 48 on a CCD 49 as a photoelectric conversion means, and the image light is converted as a digital signal by the CCD. Is output to the image information processing means of the image forming apparatus. The image information obtained as described above can be written directly on the photosensitive drum using a writing device, or can be transmitted to another FAX device using the image transmission function of the FAX device. It is possible to cope with the usage method of image information.

  As shown in FIGS. 1 and 2, an ADF 50 as an automatic document feeder is provided on the image reading device 40. The upper module including the ADF 50 and the trays is supported on the rear side of the frame 42 of the reading device 40 through a hinge portion (not shown) so that the front side can be opened widely. The ADF 50 provided together with the upper device includes a document tray 51 on which documents are stacked and set, a reverse tray 56 disposed below the document tray 51, and a discharge tray 60 positioned at the top. Of the three trays, the reversing tray 56 disposed at the lowermost portion serves as a platen cover corresponding to the large platen 43.

  In the ADF, for the document tray 51 disposed in the intermediate portion, a sheet feeding device 52 in which a retard roller and a sheet separating means are combined is provided as in the case of a general document tray. A document transport path (first document transport path) formed in a substantially horizontal U-shape between the document tray 51 and the lower reverse tray is disposed corresponding to the upstream and downstream sides of the small platen 44. An image is read by a scanning device 45 stopped under the platen 44 while conveying a document at a constant speed by a conveying roller device 55. Further, a reverse conveyance path 58 as a second conveyance path connecting the path from the discharge tray 56 and the upper portion of the first document conveyance path is a first portion in the upstream portion of the conveyance roller device 54. It is provided so as to merge with the conveyance path.

  Further, a downstream portion of the first transport path 53 of the transport roller device 54 is connected to the discharge tray 60 via a discharge path 59 via a branch portion provided with a gate G2. Note that a gate member that opens and closes and can be switched by a solenoid or the like can be used as the gate G1 disposed in the upstream portion of the reversing tray in the branch portion of the document transport path. In contrast to this, when an elastic film or the like is provided at the branching portion and the document is moved from the reading path to the reversing tray, the film is allowed to pass upward by swinging the film. When guiding toward the reversing path 58, the document can be guided by sliding on the upper surface of the film as the gate G1. Therefore, the structure of the branch guide means can be simplified by attaching the film member as described above. In order to discharge the document to the discharge tray 60 disposed at the top, the document is guided toward the discharge path 59 through the gate G2, and a driving means such as a solenoid is provided for the gate G2. It is necessary.

  In the document conveying apparatus configured as described above, when reading a single-sided document, the document is set on the document tray 51 and conveyed by the sheet feeding device 52 along the reading path 53 one by one. Then, the image is read by the conveying roller device 53 toward the reading unit, read by the scanning device 45 while being conveyed by the conveying roller device 55 at a position corresponding to the small platen 44, and discharged to the reversing tray 56. That is, in this case, the document is transported along the transport path A, and the reverse tray 56 has a function as a discharge tray. Therefore, the reverse roller device 57 completely sends the document onto the tray 56. Until the discharge operation continues.

  When the original to be read is a double-sided original, the operator inputs information indicating that the double-sided original is read in advance to the control panel of the apparatus. Therefore, when reading the first side of the document according to the document transport path A and feeding the document to the discharge tray 56, the reverse roller 57 disposed at the entrance of the tray 56 discharges the document. The document is paused before the trailing edge of the document is completely removed. Then, the operation of conveying along the conveying path B through the return path 58 through the gate G1 while feeding the original from the sheet feeding tray 56 with the rear end of the sheet nipped by the roller is shown in FIG. This is done as shown. The document that has been reversed and sent to the reading path 53 and has read the back surface (second surface) of the document may be discharged to the reversing tray 56 as it is.

  As described above, there is a problem in that when the original on which both-sided image reading has been completed is deposited on the reverse tray as it is, the page of the original is disturbed. Therefore, in order to align the pages of the document, it is sent again toward the uppermost discharge tray without being deposited on the reverse tray 56, and the pages are aligned in the same manner as when the document is set on the document tray 51. . In other words, the document sent to the reversing tray 56 is discharged along the conveying path C so that the document is again discharged from the returning path 58 through the gate G2 and the discharging path 61 to the discharging tray 60 by the reversing roller 57. Transport. Accordingly, the originals deposited on the discharge tray 60 are in a state where the first page is the bottom and the first page is facing down and the pages are aligned, so that extra work is required for post-processing. It is not necessary.

  It should be noted that setting each document transport mode for the automatic document transport apparatus can be handled by providing a document transport mode selection button or the like on the control panel of the image forming apparatus, for example. Then, when the selection button is pressed, the conveyance path shown in the schematic diagram is illuminated so that the operator can easily confirm it, so that the conveyance path of the document can be confirmed and mistakes can be prevented. It becomes possible.

1 is an explanatory diagram illustrating a configuration of an image forming apparatus. It is explanatory drawing of the structure of a double-sided ADF, and the conveyance state of a single-sided original. FIG. 6 is an explanatory diagram of an operation for reverse conveyance of a double-sided document.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus, 2 Apparatus main body, 3 Paper feed tray, 4 Paper feed roller, 6 Registration roller apparatus, 7 Paper conveyance path, 10 Recording part,
11 photosensitive drum, 12 charging means, 13 writing device,
14 transfer roller, 15 cleaner, 16 developing device,
17 developing roller, 18 fixing device, 20 discharge path,
21 discharge roller, 22 discharge tray, 23 gate,
25 Manual feed tray, 30 Duplex unit, 33 Reverse path,
40 image reading device, 43/44 platen, 45 scanning device,
48 lenses, 49 CCD, 50 ADF, 51 document tray,
52 paper feeding device, 53 reading path, 54/55 transport roller device,
56 Reverse tray, 57 Reverse roller, 58 Return path,
59 discharge path, 60 discharge tray, 61 discharge roller.

Claims (3)

An automatic document feeder provided in a reading device as image information input means of an image forming apparatus, which feeds documents set on a document tray one by one toward a reading unit and reads an image of a moving document,
A first transport path for reading an image of the document through the reading unit while guiding the document sent from the document tray on which the document is set to the reversing unit;
A document transported in a switchback shape from the reversing unit disposed at a lower portion of the document tray is capable of being guided; a second transport path that merges with the first transport path;
A first gate for guiding a document from the first transport path to the reversing unit and guiding a document returned from the reversing unit to the second transport path;
A second gate for branching the document guided along the first transport path to the discharge tray side and the reversing unit side provided on the upper side of the document tray;
A third transport path for guiding the document to the discharge tray via the second gate ;
Equipped with a,
When scanning a two-sided document,
Reading the first side of the double-sided document that is fed from the document tray and sent to the reversing unit via the first transport path and the first gate;
Next, the second surface of the double-sided document that is reversed by the reversing unit and sent to the reversing unit via the first gate, the second conveyance path, and the first conveyance path is read.
Subsequently, the sheet is reversed by the reversing unit, and discharged to the discharge tray through the first gate, the second transport path, the first transport path, the second gate, and the third transport path. An automatic document feeder characterized by the above.   2. The automatic document according to claim 1, wherein the document reversing unit is also configured as a single-sided document discharge tray, and is provided as a member having a function of a platen document pressing plate corresponding to a flatbed scanner. Conveying device. In the automatic document feeder,
Arrange the uppermost discharge tray, the middle document tray, and the lowermost reversing tray in an overlapping manner,
Connecting the document tray and the reverse tray via the first and second transport paths;
3. The automatic document feeder according to claim 1, wherein the reversing tray and the discharge tray are provided via a third conveyance path.

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