JP5380385B2 - Document conveying apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a document transport device that is used in combination with an image forming apparatus such as a copying machine and transports a document placed on a document placement unit to an image reading position, and an image forming apparatus including the document transport device.

  The document conveying device is a device that is used in combination with an image forming apparatus including an image reading unit that reads an image of a document, such as a copying machine or a facsimile. According to the document conveying device, the document placed on the document placing unit can be conveyed to the image reading position of the image reading unit in the image forming apparatus. Further, according to the document conveying device, the document that has passed through the image reading position can be discharged and stacked on the document stacking unit.

  Further, there is known a document conveying device having a function of reversing the document surface (see, for example, Patent Document 1 below). In the document conveying device described in Patent Document 1, an intermediate tray that partitions a space between the document placement unit and the document stacking unit into a first space on the document stacking unit side and a second space on the document stacking unit side, And a first document discharge unit that discharges the document toward the first space, and a second document discharge unit that discharges a portion of the document toward the second space. In the document conveying device described in Patent Document 1, the first conveying unit that conveys the document placed on the document placing unit to the image reading position, and the document located at the image reading position to the first document discharging unit. A second conveying unit that conveys the document to the second document discharge unit, a third conveying unit that conveys the document located at the image reading position to the second document discharge unit, and an image reading by switching the document back and upside down using the second space. And a fourth transport means for transporting again to the position. The first to fourth conveying means are constituted by a conveying path formed from a sheet metal member or the like, or a conveying roller pair that clamps and feeds the document.

In the document conveyance device described in Patent Document 1, when an image on only one side of a document is read (in the case of single-sided reading), the document is conveyed as follows.
The document placed on the document placement unit is conveyed to the image reading position by the first conveying unit, and the image reading unit in the image forming apparatus reads an image on one side of the document at the image reading position. Thereafter, the document from which the image has been read is transported to the first document discharge unit by the second transport unit, is discharged from the first document discharge unit, and is stacked on the document stacking unit.

Further, in the document conveying device described in Patent Document 1, when reading images on both sides of a document (in the case of duplex reading), the document is conveyed as follows.
The document placed on the document placement unit is conveyed to the image reading position by the first conveying unit, and the image reading unit in the image forming apparatus reads an image on one side of the document at the image reading position. Thereafter, the document on which the image has been read is transported to the second document discharge unit by the third transport unit, switched back using the second space by the fourth transport unit, turned upside down, and transported again to the image reading position. Is done. Then, at the image reading position, the image on the other side of the document is read by the image reading unit in the image forming apparatus. Here, the reading of the double-sided image on the original is completed, but if the original is discharged to the original stacking unit as it is, the original that has been read on one side and the original that has been read on both sides in the original stacking unit are opposite. become.

Therefore, the document read on both sides is switched back again using the second space by the third transport unit and the fourth transport unit, reversed upside down, and transported to the image reading position. Here, the image reading unit does not read the image on the document. Thereafter, the document read on both sides is transported to the first document discharge unit by the second transport unit, and is discharged from the first document discharge unit.
In this way, in the document stacking unit, the document that has been scanned on one side and the document that has been scanned on both sides are stacked in a state where the front and back sides coincide with each other. Also referred to as “Back-scanning duplex scanning method”).

In addition, when a document jam (JAM) occurs in a document transport apparatus that transports a plurality of documents, the user does not pass through an image reading position among the plurality of documents (an image is not scanned). It is necessary to sort the original document, place only the selected original document on the original placing portion again, and re-convey the original document (re-read the original document).
However, it is difficult for the user to accurately select a document that has not passed through the image reading position.

  Therefore, as a technique that eliminates the need for the user to select a document that has not passed through the image reading position, Patent Document 2 discloses that an "automatic document feeder for feeding a plurality of documents one by one to a document table, and a document. A means for determining whether or not the document has been normally conveyed; a counting unit for counting the number of documents; and a display unit for guiding an operation method to a user. To count the number of documents, hold the count value up to that time, and display the operation instruction to return all the documents to the display means, and then resume the operation until the count value is resumed. An image forming apparatus characterized in that the copying operation is continued after this is disclosed.

  According to the image forming apparatus (document conveying apparatus) described in Patent Document 2, when a document jam occurs in the document conveying apparatus, the user returns all the documents to the document placing unit and then performs a copy operation. If the (image reading operation on the original) is resumed, the original that has passed the image reading position (the original on which the image has been read) is not read and the original that has not passed the image reading position (the image) It is possible to read an image only for a document that has not been read (such an image reading method is also referred to as an “all document re-conveying method”). By realizing such an operation, the image forming apparatus described in Patent Document 2 can reduce the time required to read a document by making it unnecessary to re-read all the documents.

  There is also an original conveying apparatus that employs both the intermediate tray switchback original double-sided reading method and the full original re-conveying method.

JP 2004-29066 A Japanese Patent Laid-Open No. 2000-98821

  However, it is desired to further reduce the time required to read a document after the document is jammed in the document feeder of the intermediate tray switchback document double-sided reading method.

SUMMARY OF THE INVENTION An object of the present invention is to provide a document conveying device that can further reduce the time required to read a document after the document is jammed in the document conveying device of the intermediate tray switchback document double-sided reading method.
Another object of the present invention is to provide an image forming apparatus including the document conveying device.

  The present invention provides a document placement unit on which a document before an image is read is placed, a document stacking unit that is located below the document placement unit and that accumulates documents that have passed a predetermined image reading position, and A space between the document placement portion and the document stacking portion, and a space between the document placement portion and the document stacking portion is defined as a first space on the document stacking portion side and the document placement portion side. An intermediate tray for partitioning into the second space, a first document discharge section that faces the first space and discharges the document toward the first space, faces the second space, and places the document in the second space. A second document discharge section that discharges toward the first position, a first conveyance path between the document placement section and the image reading position, the upstream first conveyance path on the document placement section side, and the image reading The first downstream side conveyance path on the position side and the first merge located between the upstream side first conveyance path and the downstream side first conveyance path A first transport path, a first transport means for transporting a document placed on the document placement section to the image reading position through the first transport path, the image reading position, and the first document discharge section. A second transport path between the second transport path, a second transport means for transporting a document located at the image reading position to the first document discharge section through the second transport path, and the image reading position and the second document discharge. A third conveyance path between the second conveyance section, a third conveyance means for conveying the document located at the image reading position to the second document discharge section through the third conveyance path, the second document discharge section, and the second document discharge section. The fourth conveyance path between the first conveyance path and the first merging portion and the document located in the third conveyance path are switched back by using the second space, and the fourth conveyance path and the downstream side are switched. Transported again to the image reading position through the first side transport path, and A fourth conveying means for conveying an original located at the first merging portion of the conveying path toward the second original discharging section through the fourth conveying path; and a conveying destination of the original conveying the upstream first conveying path Is switched to the first transport path on the downstream side or the fourth transport path, and the second document transport destination is provided outside the second document discharge section in the second space. A second document transport destination switching unit in the second space, a transport destination of the document transported between the second document discharge unit and the second document transport destination switching unit in the second space. A second original transport destination switching unit that switches to the outer second outer space or the first space, and the original transport destination in the first original transport destination switching unit as the original transport mode. And set it on the road A normal transport mode in which the document transport destination in the second document transport destination switching unit is set in the outer second space, and a document transport destination in the first document transport destination switching unit is set in the fourth transport path; The document transport direction in the fourth transport unit is set to a direction from the first merge portion of the first transport path toward the second document discharge portion, and the document transport destination in the second document transport destination switching unit is set. The present invention relates to a document conveyance device including a conveyance mode control unit that can be changed to a short-circuit conveyance mode set in the first space.

  The conveyance mode control unit controls a first document conveyance destination control unit that controls a document conveyance destination in the first document conveyance destination switching unit and a document conveyance destination in the second document conveyance destination switching unit. A second document conveyance destination control unit; and a fourth document conveyance direction control unit that controls a document conveyance direction in the fourth conveyance unit. The conveyance mode control unit conveys the document to the image reading position. In this case, when the document transport mode is set to the normal transport mode and the document is transported to the document stacking unit without passing through the image reading position, the document transport mode is set to the short-circuit transport mode. It is preferable to do.

  In addition, when conveying a plurality of documents from the document placement unit to the document stacking unit, a document count unit that counts the number of documents that have passed through the image reading position, and a document jam in the document transport device are detected. A document jam detection unit, and when the document jam detection unit detects a document jam and the document is placed again on the document placement unit, the document from the document placement unit to the document stacking unit When the conveyance of the document is resumed, the previous document of the number of documents counted by the document count unit is conveyed in the short-circuit conveyance mode, and the next and subsequent documents after the number of documents counted by the document count unit The original is preferably conveyed in the normal conveyance mode.

  Further, the present invention provides the document conveying device, an image reading unit that reads an image of the document that has passed through the image reading position in the document conveying device, and image information related to the image of the document read by the image reading unit. And an image forming unit that forms an image on a sheet.

According to the present invention, it is possible to provide a document transport device that can further reduce the time required to read a document after the document is jammed in the document transport device of the intermediate tray switchback document double-sided reading method.
Further, according to the present invention, it is possible to provide an image forming apparatus including the document conveying device.

1 is a left side view for explaining the arrangement of components in a copying machine 1 as an embodiment of an image forming apparatus of the present invention. 6 is a schematic cross-sectional view showing a transport path of a document G in document transport apparatus 700. FIG. FIG. 7A is a perspective view illustrating a second document transport destination switching unit 460 provided on the intermediate tray 730 of the document transport apparatus 700, and FIG. 9A is a diagram illustrating a state where the transport destination of the document G is the outer second space K22. ) Is a diagram illustrating a state where the transport destination of the document G is the first space K1. FIG. 6 is a functional block diagram relating to the control of document feeder 700. FIG. 6 is a schematic cross-sectional view illustrating a conveyance path for a document G during duplex reading. FIG. 6 is a schematic cross-sectional view showing the continuation of FIG. 5. FIG. 7 is a schematic cross-sectional view showing the continuation of FIG. 6. FIG. 8 is a schematic cross-sectional view showing the continuation of FIG. 7. FIG. 5 is a schematic cross-sectional view showing a conveyance path for a document G in a short-circuit conveyance mode. 6 is a flowchart showing a conveying operation in document conveying apparatus 700.

Hereinafter, a copying machine 1 as an embodiment of an image forming apparatus of the present invention will be described with reference to the drawings. The copier 1 of the present embodiment includes an embodiment of the document conveying device 700 of the present invention.
FIG. 1 is a left side view for explaining the arrangement of components in a copier 1 as an embodiment of an image forming apparatus of the present invention. FIG. 2 is a schematic cross-sectional view showing a transport path of the document G in the document transport apparatus 700. FIG. 3 is a perspective view showing the second document transport destination switching unit 460 provided on the intermediate tray 730 of the document transport apparatus 700, and FIG. 3A shows a state where the transport destination of the document G is the outer second space K22. FIG. 4B is a diagram showing a state where the transport destination of the original G is the first space K1. In the present embodiment, the side (the right side in FIG. 1) on which a later-described manual feed tray 65 is disposed is the front side of the copier 1.

As shown in FIG. 1, the copier 1 of this embodiment includes an image reading device 200 and an apparatus main body M.
The image reading apparatus 200 includes an image reading unit 201 and a document conveying device 700. The document conveying device 700 is disposed above the image reading unit 201 in the vertical direction, and automatically conveys the document G to the image reading unit 201.
The apparatus main body M is disposed on the lower side in the vertical direction of the image reading apparatus 200 (image reading unit 201), and forms a toner image on a sheet T (sheet) based on image information from the image reading unit 201.

The image reading unit 201 will be described.
The image reading unit 201 performs predetermined processing on an illumination unit including a light source, a plurality of mirrors that form an optical path, an imaging lens, a CCD as a reading unit, and image information read by the CCD. And a CCD substrate for outputting the image information to the apparatus main body M side. The CCD reads an image formed on the original G conveyed to the image reading position J by the original conveying device 700.

  The document conveying device 700 will be described. As shown in FIGS. 1 and 2, the document conveyance device 700 includes a conveyance mechanism housing 703, a document placement unit 710, a document stacking unit 720, and an intermediate tray 730.

A transport mechanism housing 703 is a housing in which the transport mechanism in the document transport apparatus 700 is housed.
The document placing portion 710 is a portion on which the document G before the image is read is placed.
The document stacking unit 720 is a portion on the lower side in the vertical direction of the document placing unit 710 and is a portion on which the document G that has passed a predetermined image reading position J (see FIG. 2) is stacked.

  The intermediate tray 730 is disposed between the document placing unit 710 and the document stacking unit 720, and the space K between the document placing unit 710 and the document stacking unit 720 is defined as the first space K1 on the document stacking unit 720 side. This tray is divided into a second space K2 on the document placement portion 710 side.

  The document transport device 700 includes a first document discharge unit 701, a second document discharge unit 702, a document transport path R (see FIG. 2), and a transport unit 400 (see FIG. 4) inside a transport mechanism housing 703. A first document transport destination switching unit 450, a second document transport destination switching unit 460, a third document transport destination switching unit 470, and a fourth document transport destination switching unit 480.

The first document discharge unit 701 is a portion that faces the first space K1 and discharges the document G toward the first space K1.
The second document discharge unit 702 is a portion that faces the second space K2 and discharges a part of the document G toward the second space K2.

The document transport path R is a path for transporting the document G in the document transport apparatus 700. The document transport path R includes a first transport path R1, a second transport path R2, a third transport path R3, and a fourth transport path R4. The first transport path R1 is a path for transporting the document G between the document placement unit 710 and the image reading position J.
The first transport path R1 includes an upstream first transport path R11 on the document placing portion 710 side, a downstream first transport path R12 on the image reading position J side, an upstream first transport path R11, and a first downstream side. And a first junction R13 located between the conveyance path R12.

The second transport path R <b> 2 is a path for transporting the document G between the image reading position J and the first document discharge unit 701. The second transport path R2 includes an upstream second transport path R21 on the image reading position J side and a downstream second transport path R22 on the first document discharge unit 701 side.
The third transport path R3 is a path for transporting the document G between the image reading position J and the second document discharge unit 702. The third transport path R3 includes an upstream third transport path R31 on the image reading position J side and a downstream third transport path R32 on the first document discharge unit 701 side.
The upstream second transport path R21 and the upstream third transport path R31 are a common transport path. The downstream second transport path R22 and the downstream third transport path R32 extend downstream from the terminal end of the upstream second transport path R21 (upstream third transport path R31).
The fourth transport path R4 is a path for transporting the document G between the second document discharge unit 702 and the first junction R13 of the first transport path R1.

The transport unit 400 transports the document G in the document transport device 700. As shown in FIG. 4, the transport unit 400 includes a first transport unit 410 as a first transport unit, a second transport unit 420 as a second transport unit, and a third transport unit 430 as a third transport unit. And a fourth transport unit 440 as a fourth transport means.
The transport unit 400 (the first transport unit 410, the second transport unit 420, the third transport unit 430, and the fourth transport unit 440) includes a pair of rollers or a pair of rollers and pads. Specifically, as shown in FIG. 2, the conveyance unit 400 includes a first roller pair 401, a second roller pair 402, a third roller pair 403, a fourth roller pair 404, and a fifth roller pair 405. A sixth roller pair 406, a seventh roller pair 407, and an eighth roller pair 408.

The first transport unit 410 includes a first roller pair 401, a second roller pair 402, a third roller pair 403, and a fourth roller pair 404.
The second transport unit 420 includes a fifth roller pair 405 and a sixth roller pair 406.
The third transport unit 430 includes a fifth roller pair 405 and a seventh roller pair 407.
The fourth transport unit 440 includes a seventh roller pair 407 and an eighth roller pair 408.

The first roller pair 401 is disposed on the document placing portion 710 side in the upstream first transport path R11.
The second roller pair 402 is disposed downstream of the first roller pair 401 and upstream of the third roller pair 403 in the upstream first transport path R11.
The third roller pair 403 is disposed downstream of the second roller pair 402 in the upstream first transport path R11 and upstream of the first joining portion R13.
The fourth roller pair 404 is disposed on the downstream side first conveyance path R12 on the downstream side of the first junction R13 and on the upstream side of the image reading position J.

The fifth roller pair 405 is disposed in the vicinity of the downstream end portion in the upstream second transport path R21.
The sixth roller pair 406 is disposed in the vicinity of the first document discharge portion 701 in the second downstream conveyance path R22.
The seventh roller pair 407 is disposed in the vicinity of the second document discharge portion 702 in the downstream third conveyance path R32.
The eighth roller pair 408 is disposed between the first joining portion R13 and the seventh roller pair 407 in the fourth transport path R4.

The first transport unit 410 transports the document G placed on the document placement unit 710 to the image reading position J through the first transport path R1.
The second transport unit 420 transports the document G located at the image reading position J to the first document discharge unit 701 through the second transport path R2.
The third transport unit 430 transports the document G located at the image reading position J to the second document discharge unit 702 through the third transport path R3.

  The fourth transport unit 440 switches back and reverses the original G located on the third transport path R3 using the second space K2 and reverses the image through the fourth transport path R4 and the downstream first transport path R12. It is conveyed again to the reading position J. Further, the fourth transport unit 440 transports the document G located at the first junction R13 of the first transport path R1 toward the second document discharge unit 702 through the fourth transport path R4 (for this transport operation). Will be described in detail later).

  The first document transport destination switching unit 450 switches the transport destination of the document G transported on the upstream first transport path R11 to the downstream first transport path R12 or the fourth transport path R4. In other words, the first document transport destination switching unit 450 includes a first position (see FIG. 2) for transporting the document G transported on the upstream first transport path R11 to the downstream first transport path R12, and an upstream first. The document G that is transported on the transport path R11 is disposed so as to be switched (swingable) to a second position (see FIG. 9) that transports the document G to the fourth transport path R4.

  The second document transport destination switching unit 460 is provided outside the second document discharge unit 702 in the second space K2. The second document transport destination switching unit 460 determines the transport destination of the document G that transports the region K21 between the second document discharge unit 702 and the second document transport destination switching unit 460 in the second space K2. Are switched to the second outer space K22 or the first space K1 outside the second document transport destination switching unit 460. In other words, the second document transport destination switching unit 460 transports the document G transporting the region K21 in the second space K2 to the second space K22 outside the second space K2 (FIGS. 5 and 3A). )) And a second position (see FIGS. 9 and 3B) where the document G transporting the area K21 in the second space K2 is transported to the first space K1 can be switched (swinged). Is done.

As shown in FIGS. 3A and 3B, the second document transport destination switching unit 460 is formed of a plate-like member that is swingably connected to the intermediate tray 730. The intermediate tray 730 has an opening 731 at a position corresponding to the region K21 of the second space K2. The second document transport destination switching unit 460 can open and close the opening 731.
At the first position (see FIGS. 5 and 3A) in which the second document transport destination switching unit 460 closes the opening 731 (see FIGS. 5 and 3A), the top surface of the intermediate tray 730 and the top surface of the second document transport destination switching unit 460 are used. Is almost flush. For this reason, the document G transported in the area K21 of the second space K2 is transported to the outer second space K22 of the second space K2.
At the second position (see FIGS. 9 and 3B) in which the second document transport destination switching unit 460 opens the opening 731 (see FIGS. 9 and 3B), the document G transporting the region K21 in the second space K2 is It is conveyed through the opening 731 to the first space K1 positioned below the second space K2.

  As shown in FIG. 2, the third document transport destination switching unit 470 sets the transport destination of the document G transported on the upstream second transport path R21 (upstream third transport path R31) to the downstream second transport path R22. Or it switches to downstream 3rd conveyance path R32. In other words, the third document transport destination switching unit 470 transports the document G transported on the upstream second transport path R21 (upstream third transport path R31) to the downstream second transport path R22 (FIG. 1). 2) and a second position (see FIG. 5) for transporting the document G transported on the upstream second transport path R21 (upstream third transport path R31) to the downstream third transport path R32 (see FIG. 5). It is arranged so that it can swing.

The fourth document transport destination switching unit 480 switches the transport destination of the document G transported on the downstream third transport path R32 to the second space K2 via the second document discharge unit 702, or uses the second space K2. Then, the transport destination of the document G that has been switched back is switched to the fourth transport path R4. In other words, the fourth document transport destination switching unit 480 uses the first position (see FIG. 5) for transporting the document G transported on the downstream third transport path R32 to the second space K2, and the second space K2. The document G that has been switched back is disposed so as to be switched (swinged) to a second position (see FIG. 6) where the document G is conveyed to the fourth conveyance path R4.
In addition, the fourth document transport destination switching unit 480 discharges the document G that transports the fourth transport path R4 from the first joining section R13 of the first transport path R1 toward the second document discharge section 702. It is also arranged so as to be able to be switched (swinged) also at a third position (see FIG. 9) that is transported to the second space K2 via the part 702.

  A document guide 746 is disposed above the image reading position J in the vertical direction. The document guide 746 is disposed opposite to the transmission member 202 of the image reading unit 201 with a small gap in order to form a transport path for the document G at the image reading position J.

  A portion (vertical direction lower side) corresponding to the image reading position J in the transport mechanism housing 703 is opened. As a result, the original G (the surface on which the image to be read is formed) is arranged to face the transmissive member 202 constituting the reading surface in the image reading unit 201 when passing through the image reading position J.

The apparatus main body M will be described.
As shown in FIG. 1, the apparatus main body M has an image forming unit GK that forms a predetermined image on a paper T based on predetermined image information, and supplies the paper T to the image forming unit GK and an image is formed. A paper supply / discharge section KH that discharges the paper T;

  As shown in FIG. 1, the image forming unit GK includes a photosensitive drum 2, a charging unit 10, a laser scanner unit 4, a developing device 16, a toner cartridge 5, a toner supply device 6, and a transfer roller 8. A fixing unit 9.

  The paper supply / discharge unit KH includes a paper supply cassette 52, a manual feed tray 65, a registration roller pair 80, and a conveyance path L for the paper T.

  The photosensitive drum 2 is made of a cylindrical member and functions as an image carrier. The photosensitive drum 2 is disposed in the apparatus main body M in a manner that can rotate around a rotation axis perpendicular to the paper surface of FIG. An electrostatic latent image is formed on the surface of the photosensitive drum 2.

  The charging unit 10 is disposed on the upper side (upward) of the photosensitive drum 2 in the vertical direction. The charging unit 10 uniformly charges the surface of the photosensitive drum 2 positively (plus polarity).

  The laser scanner unit 4 is disposed on the upper side (upward) in the vertical direction of the photosensitive drum 2 and is separated from the photosensitive drum 2. The laser scanner unit 4 includes a laser light source (not shown), a polygon mirror, a polygon mirror driving motor, and the like.

  The laser scanner unit 4 scans and exposes the surface of the photosensitive drum 2 based on the image information output from the image reading device 200. By scanning exposure by the laser scanner unit 4, the electric charge charged on the surface of the photosensitive drum 2 is removed. As a result, an electrostatic latent image is formed on the surface of the photosensitive drum 2.

  The developing device 16 is disposed in front of the photosensitive drum 2 (on the right side in FIG. 1). The developing device 16 develops a monochrome (usually black) toner image on the electrostatic latent image formed on the photosensitive drum 2. The developing device 16 includes a developing roller 17 that can be disposed to face the photosensitive drum 2 and a stirring roller 18 for stirring the toner.

The toner cartridge 5 stores toner supplied to the developing device 16.
The toner supply device 6 supplies the toner stored in the toner cartridge 5 to the developing device 16.

  The drum cleaning unit 11 is disposed behind the photosensitive drum 2 (on the left side in FIG. 1). The drum cleaning unit 11 removes toner and deposits remaining on the surface of the photosensitive drum 2.

  The transfer roller 8 directly transfers the toner image developed on the surface of the photosensitive drum 2 onto the paper T. A transfer bias for transferring the toner image developed on the photosensitive drum 2 to the paper T is applied to the transfer roller 8 by a voltage application unit (not shown).

  The toner image developed on the surface of the photosensitive drum 2 can be indirectly transferred onto the paper T via an intermediate transfer belt or the like.

The transfer roller 8 is configured to be movable between a contact position where the transfer roller 8 is in contact with the photosensitive drum 2 and a spaced position where the transfer roller 8 is separated from the photosensitive drum 2. Specifically, the transfer roller 8 is moved to the contact position when the toner image developed on the photosensitive drum 2 is transferred to the paper T, and is moved to the separation position in other cases.
Here, the paper T is sandwiched between the photosensitive drum 2 and the transfer roller 8 and pressed against the surface of the photosensitive drum 2 (the side on which the toner image has been developed). In this way, a transfer nip N as a transfer portion is formed, and the toner image developed on the photosensitive drum 2 is transferred to the paper T.

  The fixing unit 9 melts the toner constituting the toner image transferred onto the paper T and fixes it on the paper T. The fixing unit 9 includes a heating roller 9a heated by a heater and a pressure roller 9b pressed against the heating roller 9a. The heating roller 9a and the pressure roller 9b convey the paper T onto which the toner image has been transferred so as to sandwich the paper T. By transporting the paper T so as to be sandwiched between the heating roller 9a and the pressure roller 9b, the toner transferred onto the paper T is melted and fixed on the surface of the paper T.

  The paper feed cassette 52 is disposed below the apparatus main body M (lower side in the vertical direction). The paper feed cassette 52 is arranged on the front side (right side in FIG. 1) of the apparatus main body M so as to be able to be pulled out in the horizontal direction. The paper feed cassette 52 includes a placement plate 60 on which the paper T is placed. The paper feed cassette 52 stores the paper T in a state where the paper T is stacked on the placement plate 60. The cassette paper feed unit 51 is disposed at the paper feed side end (the right side end in FIG. 1) of the paper feed cassette 52. The cassette paper feed unit 51 sends out the paper T stored in the paper feed cassette 52 to the transport path L.

  The cassette paper feeding unit 51 includes a double feed prevention mechanism including a forward feed roller 61 for taking out the paper T placed on the placement plate 60 and a roller pair 63 for feeding the paper T one by one to the transport path L. .

  A transport path L for transporting the paper T is formed between the cassette paper feed unit 51 or the manual paper feed unit 64 and the paper discharge unit 50. The conveyance path L includes a first conveyance path L1 from the cassette paper feeding unit 51 to the first junction P1, a second conveyance path L2 from the first junction P1 to the registration roller pair 80, and a transfer from the registration roller pair 80. A third conveyance path L3 to the roller 8, a fourth conveyance path L4 from the transfer roller 8 to the fixing section 9, a fifth conveyance path L5 from the fixing section 9 to the branch section P3, and a discharge section from the branch section P3. And up to 50 sixth transport paths L6.

  Moreover, the conveyance path L has the 7th conveyance path L7 from the manual feed tray 65 to the 1st confluence | merging part P1. The first merging portion P1 is a merging portion between the first conveyance path L1 that conveys the paper T from the cassette paper feeding section 51 and the seventh conveyance path L7 that conveys the paper T from the manual feed tray 65.

  A second junction P2 is disposed in the middle of the second transport path L2. Furthermore, the conveyance path L has a return conveyance path Lb from the branching part P3 to the second joining part P2. The second junction P2 is a junction between the second conveyance path L2 and the return conveyance path Lb.

  Here, a registration roller pair 80 is disposed on the upstream side (right side in FIG. 1) of the transfer roller 8 in the transport direction of the paper T. The registration roller pair 80 is a roller pair for correcting skew (oblique feeding) of the paper T and adjusting timing with the toner image.

  The return conveyance path Lb is a conveyance path that is provided so that the opposite surface (non-printing surface) to the surface that has already been printed faces the photosensitive drum 2 when performing duplex printing on the paper T.

  According to the return conveyance path Lb, the sheet T conveyed from the branching section P3 to the paper discharge section 50 side can be reversed and returned to the second conveyance path L2. A predetermined toner image is transferred onto the non-printing surface of the paper T that has been turned upside down by the return conveyance path Lb.

  A manual paper feed unit 64 is provided on the front side of the apparatus main body M (on the right side in FIG. 1) and above the paper feed cassette 52. The manual paper feed unit 64 includes a manual feed tray 65 and a paper feed roller 66. The manual feed tray 65 is attached to the vicinity of the entrance of the seventh conveyance path L7 at its base end portion so as to be rotatable (openable and closable). The manual feed tray 65 constitutes a part of the front surface of the apparatus main body M in the closed state. The paper feed roller 66 takes out the paper T placed on the manual feed tray 65 and sends it out toward the seventh transport path L7.

  The manual paper feed unit 64 feeds the paper T placed on the open manual feed tray 65 to the second transport path L2 via the seventh transport path L7 and the first junction P1.

  A paper discharge unit 50 is formed at the end of the sixth transport path L6. The paper discharge unit 50 is disposed on the upper side of the apparatus main body M. The paper discharge unit 50 opens toward the front of the apparatus main body M (to the right in FIG. 1). The paper discharge unit 50 discharges the paper T on which the toner is fixed by the fixing unit 9 to the outside of the apparatus main body M.

  On the opening side of the paper discharge unit 50, a paper discharge stacking unit M1 is formed. The paper discharge stacking unit M1 is formed on the upper surface (outer surface) of the apparatus main body M. The paper discharge stacking unit M1 is a part formed by recessing the upper surface of the apparatus main body M downward (vertically in the vertical direction). The bottom surface of the paper discharge stacking unit M1 constitutes a part of the top surface of the apparatus main body M. In the paper discharge stacking unit M1, sheets T on which a predetermined image transferred from the paper discharge unit 50 is transferred are stacked and stacked.

The image information output from the image reading unit 201 is output from the image reading apparatus 200 to the apparatus main body M.
In the apparatus main body M, the input image information is input to an image formation control unit (not shown). The image formation control unit controls the photosensitive drum 2, the charging unit 10, the laser scanner unit 4, the developing device 16, and the like that constitute the image forming unit GK based on the image information. A predetermined toner image is formed on the photosensitive drum 2 based on the image information.

  The same image as the image of the original G is transferred to the paper T conveyed to the transfer nip N formed by the photosensitive drum 2 via the conveyance path L based on the image information. The paper T on which the image is formed is discharged from the paper discharge unit 50 to the paper discharge stacking unit M1.

Next, with reference to FIG. 4, a configuration related to the control of the document conveying device 700 of the present embodiment will be described. FIG. 4 is a functional block diagram relating to control of the document feeder 700.
As shown in FIG. 4, the document conveying apparatus 700 of the present embodiment includes an operation panel 750, a passage sensor 490, an empty sensor 495, a control unit 100, a storage unit 120, a conveyance driving unit 500, and a first. A switching unit driving unit 550, a second switching unit driving unit 560, a third switching unit driving unit 570, and a fourth switching unit driving unit 580 are provided. Further, as described above, the document conveying apparatus 700 of the present embodiment includes the conveying unit 400, the first document conveying destination switching unit 450, the second document conveying destination switching unit 460, and the third document conveying destination switching unit 470. , A fourth document conveyance destination switching unit 480.

The operation panel 750 includes a panel display unit 751 and an operation input unit 752. The panel display unit 751 displays various information. For example, the panel display unit 751 displays a message prompting processing after the document jam, such as “Documents are jammed. Please take out all the documents and set them again”.
The operation input unit 752 is a part that performs input for operating the document conveying device 700, and includes, for example, various keys and a touch sensor panel. The operation input unit 752 includes, for example, a “start key” for starting (resuming) document conveyance (that is, reading of an image on a document), and a “reading surface determination key” for determining a document reading surface (single side / double side). Is included. The operation input unit 752 outputs a signal related to the input operation to the control unit 100.

  The passage sensors 490 are provided at a plurality of predetermined positions on the document conveyance path R, respectively, and detect that the document G passes a predetermined position on the document conveyance path R (the presence or absence of the document G at the predetermined position). . The passage sensor 490 includes a reading position passage sensor 491 that detects that the document G has passed the image reading position J. The passage sensor 490 outputs a predetermined signal to the control unit 100 when the document G passes a predetermined position. The reading position passage sensor 491 outputs a predetermined signal to the control unit 100 when the document G passes the image reading position J.

  The empty sensor 495 is provided in the document placement unit 710 and detects that the document G is placed on the document placement unit 710 (the presence or absence of the document G in the document placement unit 710). The empty sensor 495 outputs a predetermined signal to the control unit 100 when the document G is placed on the document placement unit 710.

  The conveyance driving unit 500 performs driving related to the conveyance of the document G in the document conveyance device 700. The transport driving unit 500 includes a first transport driving unit 510, a second transport driving unit 520, a third transport driving unit 530, and a fourth transport driving unit 540. The first transport driving unit 510, the second transport driving unit 520, the third transport driving unit 530, and the fourth transport driving unit 540 are respectively a first transport unit 410, a second transport unit 420, and a third transport in the transport unit 400. The unit 430 and the fourth transport unit 440 are driven.

  The first switching unit driving unit 550, the second switching unit driving unit 560, the third switching unit driving unit 570, and the fourth switching unit driving unit 580 are respectively a first document transport destination switching unit 450 and a second document transport destination switching unit. 460, the third document transport destination switching unit 470 and the fourth document transport destination switching unit 480 are driven.

  The control unit 100 includes a transport drive control unit 110, a transport mode control unit 130, a document count unit 190, a recovery count unit 191, a document jam detection unit 192, and a document empty detection unit 195.

  The transport drive control unit 110 includes a transport unit 400 (first transport unit 410) by the transport drive unit 500 (first transport drive unit 510, second transport drive unit 520, third transport drive unit 530, and fourth transport drive unit 540). , Control of driving of the second transport unit 420, the third transport unit 430, and the fourth transport unit 440) is performed. The transport drive control unit 110 performs predetermined drive control based on output signals from the operation input unit 752, the passage sensor 490, the empty sensor 495, and the like.

  The conveyance mode control unit 130 controls the document conveyance mode. The conveyance mode control unit 130 includes a first document conveyance destination control unit 150, a second document conveyance destination control unit 160, a third document conveyance destination control unit 170, a fourth document conveyance destination control unit 180, and a fourth document. A conveyance direction control unit 140.

  The first document transport destination control unit 150 controls the transport destination of the document G in the first document transport destination switching unit 450. Second document transport destination control unit 160 controls the transport destination of document G in second document transport destination switching unit 460. Third document conveyance destination control unit 170 controls the conveyance destination of document G in third document conveyance destination switching unit 470. Fourth document transport destination control unit 180 controls the transport destination of document G in fourth document transport destination switching unit 480. The fourth document conveyance direction control unit 140 controls the conveyance direction of the document G in the fourth conveyance unit 440.

  When the document G is transported to the image reading position J, the transport mode control unit 130 sets the document transport mode to the normal transport mode MD1. The conveyance mode control unit 130 sets the single-sided discharge conveyance mode MD3 or the double-sided discharge conveyance mode MD4 as the conveyance mode for the document G conveyed to the image reading position J in the normal conveyance mode MD1. When conveying the document G to the document stacking unit 720 without passing through the image reading position J, the conveyance mode control unit 130 sets the conveyance mode of the document G to the short-circuit conveyance mode MD2.

In the normal transport mode MD1, as shown in FIG. 2, the transport destination of the document G in the first document transport destination switching unit 450 is set to the downstream first transport path R12, and the document in the second document transport destination switching unit 460 is set. This is a transfer mode in which the transfer destination of G is set in the outer second space K22.
The single-sided discharge conveyance mode MD3 is a conveyance mode for the document G conveyed to the image reading position J in the normal conveyance mode MD1, and the conveyance destination of the document G in the third document conveyance destination switching unit 470 is set as shown in FIG. This is the transport mode set in the first space K1.

  The duplex discharge conveyance mode MD4 is a conveyance mode for the document G conveyed to the image reading position J in the normal conveyance mode MD1, and, as shown in FIGS. 5 to 7, the document G in the third document conveyance destination switching unit 470 is transferred. The transport destination is set to the second space K2, and the transport destination of the document G in the fourth document transport destination switching unit 480 is switched back using the second space K2 and turned upside down so that the fourth transport path R4 and the downstream Is set so as to be transported again to the image reading position J through the first side transport path R12, and the transport destination of the document G in the third document transport destination switching unit 470 is set to the first space K1, as shown in FIG. Mode.

  In the short-circuit transport mode MD2, the transport destination of the document G in the first document transport destination switching unit 450 is set to the fourth transport path R4, and the transport direction of the document G in the fourth transport section 440 is set to the first transport path R1. This is a conveyance mode in which the setting is made in the direction from the merging portion R13 toward the second document discharge portion 702, and the conveyance destination of the document G in the second document conveyance destination switching unit 460 is set in the first space K1.

The document count unit 190 is configured to transfer the plurality of documents G from the document placement unit 710 to the document stacking unit 720 based on an input signal from the reading position passage sensor 491 of the document G that has passed the image reading position J. Count the number.
The recovery count unit 191 realizes the operation of the above-described all document re-conveying method (a method in which an image is read only for a document that has not passed the image reading position after all the documents are returned to the document placing unit). This is a counting unit (counter).

  The document jam detection unit 192 detects jamming (JAM) of the document G in the document feeder 700 based on the output signal from the passage sensor 490. The document jam detection unit 192 determines that the document G is clogged at the predetermined position when the document G continues to be located at a predetermined position in the document transport path R for a predetermined time or more.

  The document empty detection unit 195 determines the presence or absence of the document G placed on the document placement unit 710 based on the output signal from the empty sensor 495. In addition, the document empty detection unit 195 detects that the document G has been placed again on the document placement unit 710 (after the document G has been reset, that is, after the document G has been removed from the document placement unit 710, ) Is detected.

When the control unit 100 has the above-described configuration, when the document jam detection unit 192 detects that the document G is once jammed, it is detected that the document G is placed again on the document placement unit 710. When the conveyance of the document G from the document placement unit 710 to the document stacking unit 720 is resumed, the previous document of the number of documents counted by the document counting unit 190 (that is, the document whose image has already been read). Are transported in the short-circuit transport mode MD2, and the documents subsequent to the number of documents G counted by the document count unit 190 (that is, the document whose image has not been read) are transported in the normal transport mode MD1. Then, predetermined control is performed.
Various types of information regarding the control unit 100 are stored in the storage unit 120. For example, in the storage unit 120, information on conditions for the document empty detection unit 195 to detect that the document G is placed again on the document placement unit 710 after the document jam detection unit 192 detects the document G jam. Is memorized.

  An operation for conveying the original G in the original conveying apparatus 700 of this embodiment will be briefly described. FIG. 5 is a schematic cross-sectional view showing the conveyance path of the original G at the time of duplex reading. FIG. 6 is a schematic cross-sectional view showing a continuation of FIG. FIG. 7 is a schematic cross-sectional view showing a continuation of FIG. FIG. 8 is a schematic cross-sectional view showing the continuation of FIG. FIG. 9 is a schematic cross-sectional view showing the conveyance path of the original G in the short-circuit conveyance mode.

When an image of only the A side of the original G is read (in the case of single-side reading), the original G is conveyed as follows.
As shown in FIG. 2, the document G placed on the document placement unit 710 is transported to the image reading position J by the first transport unit 410 through the first transport path R1. The image on the A side (one side) of the original G is read by the image reading unit 201 in FIG. Thereafter, the document G from which the image has been read is transported by the second transport unit 420 to the first document discharge unit 701 through the second transport path R2, is discharged from the first document discharge unit 701, and is stacked on the document stacking unit 720. The

Further, when reading images on both sides of the original G (in the case of double-side reading), the original G is conveyed as follows.
As shown in FIG. 5, the document G placed on the document placement unit 710 is transported to the image reading position J by the first transport unit 410 through the first transport path R <b> 1. The image on the A side (one side) of the original G is read by the image reading unit 201 in FIG. Thereafter, the original G from which the image has been read is conveyed to the second original discharge unit 702 through the third conveyance path R3 by the third conveyance unit 430, and a part of the original G is sandwiched between the seventh roller pair 407. Then, it is discharged into the second space K2.

  As shown in FIG. 6, the document G is switched back by the fourth transport unit 440 using the second space K2, and is turned upside down through the fourth transport path R4 and the downstream first transport path R12. It is conveyed again to position J. At the image reading position J, the image reading unit 201 in the copier 1 reads the image on the B side (the other side) of the original G.

  Here, the reading of the images on both sides (A side and B side) of the original is completed, but if the original G is discharged to the original accumulating unit 720 as it is, The original G that has been read on both sides is opposite.

Therefore, as shown in FIG. 7, the original G which has been read on both sides is switched back again by using the second space K <b> 2 by the third transport unit 430 and the fourth transport unit 440, and turned upside down. It is conveyed to the image reading position J through R4 and the downstream first conveyance path R12. Here, the image reading unit 201 does not read the image on the document G. Thereafter, the original G that has been read on both sides is conveyed by the second conveying unit 420 to the first original discharging unit 701 through the second conveying path R2, and is discharged from the first original discharging unit 701.
In this manner, in the document stacking unit 720, the document G that has been scanned on one side and the document G that has been scanned on both sides are stacked in a state where the front and back sides coincide with each other.

In the short-circuit conveyance mode, the original G is conveyed as follows.
As shown in FIG. 9, the transport destination of the document G by the first document transport destination switching unit 450 is set to the fourth transport path R4. The conveyance direction of the document G by the fourth conveyance unit 440 is set to a direction from the first junction R13 of the first conveyance path R1 toward the second document discharge unit 702. The transport destination of the document G by the second document transport destination switching unit 460 is set in the first space K1.
The document G placed on the document placement unit 710 includes an upstream first transport path R11, a first merging section R13, a fourth transport path R4, a second document discharge section 702, a region K21 in the second space K2, and The paper is transported to the first space K1 through the second document transport destination switching unit 460, and then stacked on the document stacking unit 720.

  Next, with reference to FIG. 10, a description will be given of the control related to the transport operation in the document transport apparatus 700 of the present embodiment. FIG. 10 is a flowchart showing a transport operation in the document transport apparatus 700.

  As shown in FIG. 10, when the start key of the operation input unit 752 is turned on by the user, the counter value N of the document count unit 190 is reset to “N = 0” in step ST1.

  In step ST2, the control unit 100 controls the transport driving unit 500, the first switching unit driving unit 550, the third switching unit driving unit 570, etc., and the transport unit 400, the first document transport destination switching unit 450, the third document. The transport destination switching unit 470 and the like are driven. As a result, the document G is transported toward a predetermined transport destination.

  In step ST3, the document jam detection unit 192 determines whether or not the document G is jammed (JAM). If the document jam detection unit 192 does not detect the document G jam (NO), the process proceeds to step ST4. On the other hand, when the document jam detection unit 192 detects the document G jam (YES), the process proceeds to step ST7.

  In step ST4, an image is read from the document G that has passed the image reading position J.

  In step ST5, “1” is added to the counter value N of the document count unit 190 by “N = N + 1”.

  In step ST <b> 6, the document empty detection unit 195 determines whether there is a document G (next document) placed on the document placement unit 710. When the document empty detection unit 195 detects the document G placed on the document placement unit 710 (YES), the process returns to step ST2, and steps ST2 to ST5 are repeated. On the other hand, when the document empty detection unit 195 does not detect the document G placed on the document placement unit 710 (NO), the conveyance process of the document G is ended.

Next, the processing after the document jam detection unit 192 detects a jam of the document G (YES) in step ST3 will be described.
In step ST7, a message prompting the processing after the document jam is displayed on the panel display unit 751 of the operation panel 750, for example, “Documents are jammed. Please remove all documents and reset them.” Is done.

In step ST8, the document empty detection unit 195 determines whether or not the document G is reset, that is, whether or not the document G is placed on the document placement unit 710 from the state where the document G is placed. Is detected.
The detection of the resetting of the original G is based on the display in step ST7, the original that has become jammed, the original that exists in the original conveyance path R, the original that has been discharged to the original stacking unit 720, and the original that is placed on the original placement unit 710. All the originals such as the originals being taken out are temporarily taken out by the user, and all the originals are aligned to the state before the start of copying (original reading) and returned (reset) to the original placement unit 710. Is done.

If the document empty detection unit 195 detects that the document G has been reset (YES), the process proceeds to step ST9. On the other hand, when the document empty detection unit 195 does not detect that the document G has been reset (NO), step ST7 is maintained.
When the output of the signal from the empty sensor 495 does not change, for example, the display in step ST7 is continued until a reset instruction is given by the user.

In step ST9, “0” is set in n of the recovery count unit 191.
In step ST10, for example, a message “Please press the start key” is displayed on the panel display section 751 of the operation panel 750.

  In step ST11, it is determined whether the start key of the operation input unit 752 is on / off. If the start key is turned on by the user in response to the display in step ST10 (YES), the process proceeds to step ST12. On the other hand, if the start key is not turned on (NO), step ST10 is maintained.

When the start key is turned on in step ST11 (YES), in step ST12, the conveyance mode control unit 130 sets the document conveyance mode to the short-circuit conveyance mode MD2.
Specifically, as shown in FIG. 9, the first document transport destination control unit 150 controls the first switching unit driving unit 550 and sets the transport destination of the document G in the first document transport destination switching unit 450 to the fourth. Set to transport path R4. The fourth document conveyance direction control unit 140 controls the fourth conveyance driving unit 540 so that the document G is conveyed in the fourth conveyance unit 440 in the second conveyance direction from the first junction R13 of the first conveyance path R1. The direction is set toward the unit 702. The second document transport destination control unit 160 controls the second switching unit driving unit 560 to set the transport destination of the document G in the second document transport destination switching unit 460 to the first space K1.

  In step ST13, the document G placed on the document placement unit 710 is conveyed again. Since the document transport mode is set to the short-circuit transport mode MD2, the document G placed on the document placing unit 710 is the upstream first transport path R11, the first joining section R13, and the fourth transport path R4. Then, the paper is transported to the first space K1 through the second document discharge unit 702, the area K21 of the second space K2, and the second document transport destination switching unit 460, and then stacked on the document stacking unit 720.

  In step ST14, n of the recovery count unit 191 is incremented by “1” every time one document is conveyed.

In step ST15, it is determined whether or not the value N of the document count unit 190 and the value n of the recovery count unit 191 are “n = N”.
If “n ≠ N” (NO), the process returns to step ST13. The image reading (copying) is normally performed up to the Nth original, and the N + 1th original is clogged. Therefore, by continuing the document skip operation until “n = N” is satisfied, the document whose image reading operation has already been completed is directly discharged to the document stacking unit 720. That is, up to the Nth document G is conveyed (idle feed) without performing an image reading (copying) operation.

On the other hand, if “n = N” in step ST15 (YES), the process proceeds to step ST16.
In step ST16, the conveyance mode control unit 130 sets the document conveyance mode to the normal conveyance mode MD1. Specifically, as shown in FIG. 2 or 5, the first document transport destination control unit 150 controls the first switching unit driving unit 550, and transports the document G in the first document transport destination switching unit 450. Is set in the downstream first transport path R12. The second document transport destination control unit 160 controls the second switching unit driving unit 560 to set the transport destination of the document G in the second document transport destination switching unit 460 in the outer second space K22.

  After the document transport mode is set to the normal transport mode MD1 in step ST16, the process returns to step ST2. By transferring the (N + 1) th document to the image reading position J, steps ST2 to ST6 are repeated from the (N + 1) th document G for which the image reading operation has not been completed, and the image reading operation for the remaining documents is performed. Is repeated.

  Note that when the (N + 1) th original is discharged to the original stacking unit 720 before the Nth original, the order of the originals changes, so this situation needs to be avoided. For example, in the document transport device 700, the drive pulse of the transport drive unit 500 is monitored to ensure that the Nth document is discharged to the document stacking unit 720 before the N + 1th document. Control is performed so that the (N + 1) th original is transported to the image reading position J after the movement pulse amount for detecting the original of the eye to be discharged to the original stacking unit 720 is detected.

  In the example described above, an example of repeating “one original conveyance → one image reading”, which can be applied to an analog type copier, has been shown. However, in the case of a digital copier, the above-described operation is performed. In addition, for example, image information of a document that has been normally conveyed is sequentially stored in the storage unit 120, and image data that is already stored in the storage unit 120 when the document is jammed and the document is conveyed again. The subsequent image data after the original may be further stored sequentially, and the image reading operation for all the originals may be started in a lump after all the image data is stored. Further, when a document jam occurs, image forming operations corresponding to image data already stored in the storage unit 120 may be performed in parallel while the document is being fed forward.

According to the document conveying device 700 of the present embodiment, for example, the following effects are achieved.
The document transport apparatus 700 of the present embodiment is a first document transport destination switching unit that switches the transport destination of the document G transported on the upstream first transport path R11 to the downstream first transport path R12 or the fourth transport path R4. 450, a second document transport destination switching unit 460 provided outside the second document discharge unit 702 in the second space K2, and the second document discharge unit 702 and the second document transport destination in the second space K2. Second document transport for switching the transport destination of the document G that transports K21 to and from the switching unit 460 to the outer second space K22 or the first space K1 outside the second document transport destination switching unit 460 in the second space K2. As the document transfer mode of the destination switching unit 460, the conveyance destination of the document G in the first document conveyance destination switching unit 450 is set to the downstream first conveyance path R12 and the second document conveyance destination is switched. The normal conveyance mode MD1 in which the conveyance destination of the original G in the unit 460 is set in the outer second space K22, and the conveyance destination of the original G in the first original conveyance destination switching unit 450 is set in the fourth conveyance path R4 and the fourth conveyance. The conveyance direction of the original G in the section 440 is set to the direction from the first merge section R13 to the second original discharge section 702 in the first conveyance path R1, and the conveyance destination of the original G in the second original conveyance destination switching section 460 is set to the first. A conveyance mode control unit 130 that can be changed to a short-circuit conveyance mode MD2 set in one space K.

  Therefore, when the document G is jammed in the document conveying device 700, if the user returns all the documents to the document placement unit and then restarts the copy operation (image reading operation on the document), the image reading position For a document G that has passed J (a document from which an image has been read), an image is not read, and only a document G that has not passed the image reading position J (a document from which an image has not been read) is read. Can be done. When reading an image only on a document G that has not passed the image reading position J (a document on which an image has not been read), the document G (image that has already passed the image reading position J in the short-circuit conveyance mode MD2). Can be discharged to the document stacking unit 720 through the fourth transport path R4, the second document transport destination switching unit 460, and the like without passing the image reading position J again. Therefore, it is possible to further reduce the time required for reading the document.

Further, according to the document conveying device 700 of the present embodiment, it is not necessary to unnecessarily pass the document G to the image reading position J, so that the document G is damaged due to the document G passing the image reading position J. Can be reduced.
Further, the document conveying apparatus 700 of the present embodiment can be realized by a relatively simple configuration change based on the conventional intermediate tray switchback document duplex reading type document conveying apparatus, so that the structure is relatively simple. At the same time, the cost increase of the apparatus can be minimized.

Further, the document conveying apparatus 700 of the present embodiment counts the number of documents G that have passed the image reading position J when a plurality of documents G are conveyed from the document placing unit 710 to the document stacking unit 720. And a document jam detector 192 that detects jam of the document G in the document feeder 700. Further, in the document conveying device 700 of the present embodiment, when the document jam detection unit 192 does not detect the document G jam after the document jam detection unit 192 detects the document G jam (that is, the document is reset). When the conveyance of the document G from the document placement unit 710 to the document stacking unit 720 is resumed, the previous document of the number (N) of documents counted by the document counting unit 190 is short-circuited. Documents transported in mode MD2 and subsequent to (N + 1) documents after the number (N) of documents counted by document count unit 190 are transported in normal transport mode MD1.
Therefore, it is possible to easily realize the document transport operation by the all document re-transport method.

As mentioned above, although preferred embodiment was described, this invention can be implemented with a various form, without being limited to embodiment mentioned above.
For example, the configuration of the second document conveyance destination switching unit 460 is not limited to the configuration that can be opened and closed to the intermediate tray 730, and can be provided on a member other than the intermediate tray 730. The second document transport destination switching unit 460 can be provided in the vicinity of the second document discharge unit 702 in the second space K2.
The image forming apparatus is not limited to a monochrome copying machine, and may be a color copying machine, a printer, a facsimile, or a complex machine of these.

  DESCRIPTION OF SYMBOLS 1 ... Copy machine (image forming apparatus) 130 ... Conveyance mode control part 140 ... 4 Original conveyance direction control part 150 ... First original conveyance destination control part 160 ... Second original conveyance destination control part , 190... Document count section, 192... Document jam detection section, 201... Image reading section, 410... First transport section (first transport means), 420. 430... Third transport unit (third transport unit) 440... Fourth transport unit (fourth transport unit) 450... First document transport destination switching unit 460. , 700... Document conveying device, 701... First document discharge section, 702... Second document discharge section, 710... Document placement section, 720. Original, GK: Image forming unit, J: Image reading position, K: Space, K1 ... 1st space, K2 ... 2nd space, K21 ... Between 2nd document discharge part and 2nd document conveyance destination switching part, K22 ... Outside 2nd space, R1 ... 1st conveyance path, R11 ... ... upstream first transport path, R12 ... downstream first transport path, R13 ... first junction, R2 ... second transport path, R3 ... third transport path, R4 ... fourth transport path

Claims (4)

A document placement portion on which a document before an image is read is placed;
A document stacking unit that is positioned below the document placing unit and that stacks documents that have passed through a predetermined image reading position;
The space between the document placement portion and the document stacking portion is arranged between the first space on the document stacking portion side and the space on the document stacking portion side. An intermediate tray that partitions into a second space;
A first document discharge section that faces the first space and discharges the document toward the first space;
A second document discharger that faces the second space and discharges the document toward the second space;
A first conveyance path between the document placement unit and the image reading position, the upstream first conveyance path on the document placement unit side, the downstream first conveyance path on the image reading position side, and the A first conveyance path having a first junction located between the upstream first conveyance path and the downstream first conveyance path;
First transport means for transporting a document placed on the document placement section to the image reading position through the first transport path;
A second conveyance path between the image reading position and the first document discharge section;
Second conveying means for conveying the document located at the image reading position to the first document discharge section through the second conveying path;
A third conveyance path between the image reading position and the second document discharge portion;
Third transport means for transporting the document located at the image reading position to the second document discharge section through the third transport path;
A fourth conveyance path between the second document discharge section and the first merging section of the first conveyance path;
The document located in the third conveyance path is switched back using the second space and conveyed again to the image reading position through the fourth conveyance path and the downstream first conveyance path, and the first Fourth conveying means for conveying an original located at the first merging portion of one conveying path toward the second original discharging portion through the fourth conveying path;
A first document transport destination switching unit that switches a transport destination of a document transported on the upstream first transport path to the downstream first transport path or the fourth transport path;
A second document transport destination switching unit provided outside the second document discharge unit in the second space, the second document discharge unit and the second document transport destination switching unit in the second space; A second document transport destination switching unit that switches a transport destination of the document transported between the second space outside the second document transport destination switching unit in the second space or the first space;
As the document transport mode, the document transport destination in the first document transport destination switching unit is set to the downstream first transport path, and the document transport destination in the second document transport destination switching unit is set to the outer second space. A normal conveyance mode set to, a document conveyance destination in the first document conveyance destination switching unit is set to the fourth conveyance path, and a document conveyance direction in the fourth conveyance unit is set to the first conveyance path in the first conveyance path. A conveyance mode control unit that is set in a direction from one merging unit to the second document discharge unit and can be changed to a short-circuit conveyance mode in which the document conveyance destination in the second document conveyance destination switching unit is set in the first space. When,
A document conveying device comprising: The transport mode control unit controls a first document transport destination control unit that controls a document transport destination in the first document transport destination switching unit and a second document control unit that controls a document transport destination in the second document transport destination switching unit. A document conveyance destination control unit, and a fourth document conveyance direction control unit that controls a document conveyance direction in the fourth conveyance unit,
When the document is transported to the image reading position, the transport mode control unit sets the document transport mode to the normal transport mode, and transports the document to the document stacking unit without passing through the image reading position. The document conveying apparatus according to claim 1, wherein the document conveying mode is set to the short-circuit conveying mode. A document counting unit that counts the number of documents that have passed through the image reading position when a plurality of documents are conveyed from the document placing unit to the document stacking unit;
A document jam detection unit for detecting document jam in the document conveying device,
When the original document is placed on the original placement unit again after the original jam detection unit detects the original jam, when the conveyance of the original from the original placement unit to the original stacking unit is resumed, Documents before the number of documents counted by the document count unit are conveyed in the short-circuit conveyance mode, and documents following the number of documents counted by the document count unit are conveyed in the normal conveyance mode. The document conveying device according to claim 2, which conveys the document. An original conveying apparatus according to any one of claims 1 to 3,
An image reading unit that reads an image of the document that has passed through the image reading position in the document conveying device;
An image forming unit that forms an image on a sheet based on image information relating to an image of the document read by the image reading unit;
An image forming apparatus comprising:

Images