JP2013180889A - Document reading device, image forming device and document reading method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently and appropriately convey even a document not formed at a right angle in an end thereof.SOLUTION: In a document reading part 8, skew sensors 47 detect an end of a document G being conveyed while being regulated in positions of both side end surfaces thereof by document side guide members 41a and 41. When the skewed amount of the document G calculated by a CPU based on a result of the detection is a set value or more, a guide moving mechanism part 42 positions the document side guide members 41a and 41b to positions of the document side end surfaces, and a stopper switching solenoid 49 moves a stopper member 48 to a retreat position. When the skewed amount is smaller than the set value, the guide moving mechanism part 42 moves the document side guide members 41a and 41b to a direction of separating from the document side end surfaces, and the stopper switching solenoid 49 positions the stopper member 48 to a stop position so that the end surface of the document G abuts on the stopper member 48, and thereafter, moves the stopper member 48 to the retreat position.

Description

  The present invention relates to an original reading apparatus, an image forming apparatus, and an original reading method, and more particularly, to an original reading apparatus, an image forming apparatus, and an original reading method for efficiently and appropriately conveying an original.

  Document reading devices such as scanner devices, copying devices, and composite devices, and image forming devices equipped with the document reading device, particularly in a document reading device that reads a conveyed document with a stationary document reading unit, are set on a document table. A document reading unit that guides a side end surface extending in the document conveyance direction by a document side guide member, conveys the document on a reading position of the document reading unit by a conveyance roller, and stops the image of the document to be conveyed , And the document that has been read is discharged onto the discharge tray.

  In the conventional document reading apparatus, in document conveyance, the leading edge of the document is abutted against a conveyance roller or a stopper member arranged at right angles to the conveyance direction, and the document side end surface is also aligned with the document side guide member. The document skew (inclination with respect to the document conveyance direction) is prevented by inserting the document into the conveyance path while guiding (guide).

  Conventionally, a technique has been proposed in which the skew of the leading edge of the document is detected by a detection sensor, and when the leading edge of the document is not perpendicular to the document transportation direction, the transportation of the document is stopped (see Patent Document 1).

  However, there are originals whose front end surface is not perpendicular to the side end surface. If a document whose front end surface is non-perpendicular is abutted against a conveyance roller or a stopper member and the original conveyance direction is corrected, conversely, The side end surface of the document is skewed with respect to the transport direction, and if the transport of the document is stopped each time a document whose tip surface is not perpendicular to the side end surface is detected, the workability is poor. was there.

  Therefore, conventionally, the operator determines whether or not the leading end of the document transported to the stopper member that corrects the leading end surface of the document at a right angle with respect to the document transporting direction by contacting the leading end of the document is perpendicular to the document transporting direction. It has been proposed to visually check to determine whether or not to retract the stopper member and to perform the stopper member retracting operation. That is, when the operator determines that the document front end surface is not a right angle with respect to the document side end surface, the manipulator is operated by operating a changeover switch or the like so that the document front end does not hit the stopper member, and the front end A technique has been proposed in which a non-right-angled document is prevented from skewing when it strikes against a stopper member (see Patent Document 2).

  However, in the prior art described in the above publication, an operator visually confirms a document with a non-perpendicular tip and prevents the document from being skewed by the stopper member when the document is on the stopper member. Therefore, in the case of a document originally skewed to the vicinity of the stopper member, even if it can be avoided to contact the stopper member, the skew cannot be corrected, When the original is a long document, the document is moved on the document side guide member guided by the document side end surface or the contact between the document side guide member and the side end surface of the document becomes stronger as the document is conveyed. There is a risk of damage.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to suppress the occurrence of an abnormality such as a document break while suppressing skew even for a document whose front end surface is not perpendicular to the side end surface, and to efficiently transport the document. Yes.

  In order to achieve the above object, the document reading apparatus according to claim 1 regulates the positions of both end surfaces of the document in the transport direction conveyed to the image reading means for reading the image of the document, and also with respect to the transport direction. Document side guide means that can move in the direction of the document width orthogonal to each other, guide moving means that moves the document side guide means in the document width direction, and the position of the both end surfaces of the document side guide means are conveyed while being regulated. A document leading edge detecting means for detecting the leading edge position of the document in at least two places; a calculating means for calculating a skew amount of the document based on a detection result of the document leading edge detecting means; and a document than the document leading edge detecting means. Disposed at the downstream side in the transport direction, the leading end abutment is movable to a leading end abutting position where the leading end of the document abuts and a retracted position through which the document can pass. A member, a tip abutting member moving means for moving the tip abutting member to the tip abutting position and the retracted position, and a skew amount calculated by the calculating means is equal to or greater than a preset set value. The document side guide means is positioned at a position that regulates the positions of the both side end faces, and the leading end abutting member is moved to the retracted position by the leading end abutting member moving means. The document side guide means is moved away from the document side end face by the guide moving means, and the leading end abutting member is positioned at the leading end abutting position by the leading end abutting member moving means. And a control means for moving the leading edge abutting member to the retracted position after the leading edge surface of the document abuts against the leading edge abutting member. It is characterized in that it comprises a.

  According to the present invention, even for a document whose front end surface is non-perpendicular to the side end surface, it is possible to suppress the occurrence of abnormality such as document breakage while suppressing skew, and to efficiently transport the document.

1 is a schematic front view of a digital copying apparatus to which an embodiment of the present invention is applied. The principal part top view of a manuscript reading part. The principal part side view of a manuscript reading part. FIG. 2 is a block diagram of a main part of a digital copying apparatus. 6 is a flowchart showing document reading control processing. FIG. 6 is a plan view of a main part of the document reading unit in a state where the document side guide member is retracted and the document is abutted against the stopper member. FIG. 3 is a plan view of a main part of a document reading unit in a state where a document with a non-right-angled front end surface is conveyed to a skew line placement. The principal part top view of the original document reading part in the state which is conveying the original document only with the guide of a document side guide member.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, since the Example described below is a suitable Example of this invention, various technically preferable restrictions are attached | subjected, However, The range of this invention is unduly limited by the following description. However, not all the configurations described in the present embodiment are essential constituent elements of the present invention.

  1 to 8 are diagrams showing an embodiment of an original reading apparatus, an image forming apparatus, and an original reading method according to the present invention. FIG. 1 shows an original reading apparatus, an image forming apparatus, and an original reading method according to the present invention. 1 is a schematic front view of a configuration of a digital copying apparatus 1 to which an embodiment is applied.

  In FIG. 1, a digital copying apparatus (image reading apparatus, image forming apparatus) 1 includes a paper feed unit 3, a transport unit 4, an image forming unit 5, a fixing unit 6, a paper discharge unit 7, and a document in a main body housing 2. A reading unit 8 and the like are accommodated, and a manual feed tray 10, a document table 11, a paper discharge tray 12, an operation unit 13, a document discharge tray 14, and the like are further provided. The digital copying apparatus 1 is compatible with wide paper and wide originals.

  The operation unit 13 includes various keys necessary for operating the digital copying apparatus 1, and includes a lamp such as a display (for example, a liquid crystal display) or an LED (Light Emitting Diode). The operation unit 13 performs various operations necessary for print processing, copy processing, scanner processing, and the like using the digital copying apparatus 1 and various operations in document reading processing as will be described later from the operation keys. The contents of the command input from the key and various information notified to the user from the digital copying apparatus are displayed.

  A plurality of sheets P are set in the sheet feeding unit 3, and the conveying unit 4 includes a registration roller 21 and the like. 5 to transport. The transport unit 4 also transports the paper P set on the manual feed tray 10 to the image forming unit 5 after adjusting the timing with the registration rollers 21.

  The image forming unit 5 includes a charging unit, an optical writing unit, a developing unit, a transfer unit, a cleaning unit, and the like around a photosensitive member 22 that is driven to rotate counterclockwise in FIG. The body 22 is uniformly charged (for example, charged to −1200 V). In the image forming unit 5, the optical writing unit 23 irradiates the photosensitive member 22 uniformly charged by the charging unit with light whose lighting is controlled based on the image data of the document read by the document reading unit 8. The electrostatic latent image is formed by eliminating the charge on the surface of the photosensitive member 22 where the light is irradiated, and the developing unit attaches toner to the photosensitive member 22 on which the electrostatic latent image is formed, thereby forming the toner image. Form. The image forming unit 5 transfers the toner image formed on the photosensitive member 22 to the paper P conveyed from the paper feeding unit 3 by the transfer unit, and separates the transferred paper P by the separation charger to fix the toner image. 6 to transport. In addition, the image forming unit 5 cleans the residual toner on the photosensitive member 22 that has been transferred by the cleaning unit, discharges the cleanly cleaned photosensitive member 22 by the discharging unit, and then uniformly charges the charging unit by the charging unit. Then, it is again used for image formation.

  A paper folding device 30 is connected to the digital copying apparatus 1 on the back side of the main body housing 2, and the paper folding device 30 performs end face folding, bellows-like folding, etc., on the image-formed paper P. Folding process is performed. The paper folding device 30 includes a connection portion 31 with the main body housing 2, an ear folding portion 32 that folds the ears of the paper P, a bellows folding portion 33 that folds the paper P in a bellows shape in the transport direction, and a transport that changes the transport direction by 90 °. The switching device 34, the cross folding device (not shown), the reversing device 35 for reversing the front and back, the paper P rotated by 90 °, for example, the rotating device 36 for switching the A4 landscape to the A4 portrait and the folded paper P are discharged. A tray 37 or the like for stacking is provided.

  The digital copying apparatus 1 discharges the paper P, which has been image-formed by the image forming unit 5 and has been fixed by the fixing unit 6, to the paper folding device 30 when post-processing such as paper folding is performed by the paper discharge unit 7. When paper folding is not performed, the paper is discharged to the paper discharge tray 12 by a switching claw not shown.

  The paper folding device 30 folds corners of the paper P with the ear folds 32 and then folds the bellows into the bellows with the bellows folds 33 when folding the paper P on the image. It is sent to the transfer switching device 34. The folding device 30 switches the transport direction of the fed paper P by the transport switching device 34, folds the short direction of the paper P folded bellows by the cross folding device, and turns the front and back by the reversing device 35. The paper is reversed, and further, the paper direction is rotated by a rotating device and stacked on the tray 37.

  In the digital copying apparatus 1, the document reading unit 8 is configured as shown in FIGS. 2 and 3, and the document reading unit 8 is configured to transport the document G (sub-scanning direction: an arrow in FIG. 2). The direction of the original plate 11, the pair of original side guide members 41 a and 41 b, the guide moving mechanism unit 42, the original insertion detection sensor 43, the insertion roller 44, and the insertion roller 44 are rotated from the front side. Insertion roller driving motor 45, registration sensor 46, two skew sensors 47, stopper member 48, stopper switching solenoid 49, front conveying roller 50, image reading sensor unit 51 and rear conveying roller 52, driving pulleys 53 and 54, and driving belt 55 Etc.

  The document side guide members (document side guide means) 41a and 41b are arranged on the document table 11 so as to be movable in the document width direction (main scanning direction: the direction indicated by arrow B in FIG. 2). The original G set on the upper side is moved in accordance with both end surfaces in the width direction. The document side guide members 41 a and 41 b regulate the positions of both end surfaces of the document G that is transported in the transport direction A.

  The document side guide members 41 a and 41 b are moved in the document width direction in conjunction with each other by the guide moving mechanism unit 42. In this embodiment, the guide moving mechanism section 42 includes rack gears 42a and 42b attached to the document side guide members 41a and 41b, a rack gear 42a, and a pinion gear 42c that moves the rack gear 42b in conjunction with each other. For example, when the operator operates to move one of the document side guide members 41a and 41b in the document width direction, the rack gears 42a and 42b are interlocked and moved in the same opening direction or closing direction via the pinion gear 42c.

  The document side guide members 41a and 41b are driven by a guide drive motor 56 shown in FIG. 4 and move in the document width direction. The guide moving mechanism 42 and the guide drive motor 56 function as guide moving means as a whole.

  The document insertion detection sensor 43 detects the document G that has been set on the document table 11 and inserted to a position where it contacts the insertion roller 44, and outputs the detection result to the controller 70 (see FIG. 4).

  The insertion roller 44 is disposed over the length of the maximum document width in the document width direction. The insertion roller 44 rotates in the clockwise direction indicated by the arrow in FIG. The originals are conveyed one by one in the reading sensor unit 51 direction (conveyance direction) A. The insertion roller drive motor 45 is driven and controlled by the controller 70 shown in FIG. 4. For example, when a reading start instruction operation is performed by the operation unit 13, the controller 70 detects the document G by the document insertion detection sensor 43. Then, the rotation of the insertion roller drive motor 45 is started and the registration sensor 46 detects the leading edge of the document G, and then the document G is a predetermined amount, for example, a distance that the leading edge of the document G reaches the detection area of the skew sensor 47. Rotate and drive only the two parts that are transported, and then stop.

  The registration sensor 46 detects the document G conveyed by the insertion roller 44 and outputs the detection result to the controller 70.

  Two skew sensors (document leading edge detection means) 47 are disposed at the same position in the document conveying direction A and are separated by a predetermined amount in the document width direction B. The number of skew sensors 47 in this embodiment is as follows. Although the number is two, the number is not limited to two, and any number of two or more may be used as long as the amount is suitable for calculating the skew amount of the document G.

  The skew sensor 47 is a sensor that accurately detects the position of the leading edge of the document G. In this embodiment, an image sensor such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) is used.

  The skew sensor 47 detects the pixel position of the leading edge of the document G that is fed while the positions of both end surfaces are regulated by the document side guide members 41 a and 41 b, and outputs the detection result to the controller 70.

  The controller 70 calculates the skew amount SU of the document G from the pixel position of the document G detected by the skew sensor 47. The calculation of the skew amount SU will be described in detail later.

  The stopper member (front end abutting member) 48 is a plate-like member extending in the document width direction, and the front end side in the conveyance direction is formed with a plurality of plate-like stop teeth 48a having a predetermined width. Is formed in an L shape bent 90 degrees, and a support shaft is attached to an end portion on the opposite side to the stop direction 48a bent in the L shape, and the support shaft is the center of FIG. As shown by the solid line and the alternate long and short dash line, the stop position where the document G abuts against the stop tooth 48a (the position indicated by the solid line: the leading end abutting position) and the retreat position (the position indicated by the alternate long and short dash line) for retreating from the conveyance position of the original G And is rotatably supported.

  The stopper member 48 is connected to a stopper switching solenoid (tip abutting member moving means) 49. The stopper switching solenoid 49 operates under the control of the controller 70 to move the stopper member 48 between the stop position and the retracted position. Move.

  The front conveying roller 50 is disposed in the document width direction over the length of the maximum document width, and is rotationally driven by the drive pulley 53 so that the document G sent through the stopper member 48 is read by the image reading sensor. It conveys to the part 51.

  The post-conveying roller 52 is disposed over the length of the maximum document width in the document width direction, and is rotationally driven by the drive pulley 54 to discharge the document G on which an image is read by the image reading sensor unit 51. It is discharged and conveyed to the tray 14.

  The driving pulley 53 of the front conveying roller 50 and the driving pulley 54 of the rear conveying roller 52 are connected by a driving belt 55. When the driving pulley 53 is rotationally driven by the conveying roller 57 (see FIG. 4), the driving pulley 53 is driven. The drive pulley 54 is also rotated via the belt 55.

  The image reading sensor section (image reading means) 51 contains an image sensor such as a CCD or CMOS, a SELFOC lens (registered trademark), a light source, etc. in a case, and a contact glass 51a is disposed at the upper end thereof. The document G is conveyed on the contact glass 51a.

  As shown in FIG. 3, a white reference plate 56 is disposed above the contact glass 51a of the image reading sensor unit 51. The white reference plate 56 closely contacts the conveyed document G with the contact glass 51a. And providing a white reference value for shading correction.

  As shown in FIG. 4, the main part of the digital copying apparatus 1 is configured as a block. The digital copying apparatus 1 includes the image forming unit 5, the document reading unit 8, the operation unit 13, and the like. An image memory 80 and the like are provided.

  The image memory 8 is composed of a hard disk or the like, and stores image data and the like of the original G read by the original reading unit 8 under the control of the controller 70.

  The controller 70 includes a CPU (Central Processing Unit) 71, a ROM (Read Only Memory) 72, a RAM (Random Access Memory) 73, an image processing unit 74, and the like.

  The ROM 72 stores programs such as a basic program of the digital copying apparatus 1 and a document reading control program of the present invention and necessary system data in advance, and the RAM 73 is used as a work memory of the CPU 71.

  A CPU (calculation means, control means) 71 executes basic processing as the digital copying apparatus 1 by controlling each part of the digital copying apparatus 1 while using the RAM 73 as a work memory based on a program in the ROM 72. At the same time, the document reading process in the document reading unit 8 of the present invention is controlled.

  That is, the digital copying apparatus 1 includes a ROM, an EEPROM (Electrically Erasable and Programmable Read Only Memory), an EPROM, a flash memory, a flexible disk, a CD-ROM (Compact Disc Read Only Memory), a CD-RW (Compact Disc Rewritable), a DVD. A document reading control program for executing the document reading method of the present invention recorded on a computer-readable recording medium such as a (Digital Versatile Disk), an SD (Secure Digital) card, or an MO (Magneto-Optical Disc) is read. By introducing it into the ROM 72, the image memory 80, etc., even for a document whose front end surface, which will be described later, is non-perpendicular to the side end surface, the occurrence of an abnormality such as document breakage is suppressed while suppressing skew, and the document is efficiently Reading apparatus and image reading apparatus for executing document reading method for conveying document It is constructed as an image forming apparatus equipped with a device. This document reading control program is a computer-executable program written in a legacy programming language such as assembler, C, C ++, C #, Java (registered trademark), or an object-oriented programming language, and is stored in the recording medium. And can be distributed.

  The image processing unit 74 is externally connected to the image data of the document read by the document reading unit 8 under the control of the CPU 71 through image processing necessary for image formation by the image forming unit 5 and an interface (not shown). Image processing necessary for reporting to the apparatus (computer, printer, etc.), and further, image processing necessary for image formation by the image forming unit 5 is performed on the image data sent from the external apparatus.

  Next, the operation of this embodiment will be described. The digital copying apparatus 1 according to the present embodiment also suppresses the occurrence of abnormalities such as document breakage while suppressing skew even for the document G whose front end surface is not perpendicular to the side end surface, and efficiently transports the document. Do.

  That is, in the digital copying apparatus 1, when reading the original G, as shown in FIG. 5, the user places the original side of the original G in the width direction on the original side guide members 41a and 41b. 11 (step S101), the original G is inserted in the transport direction and abutted against the insertion roller 44 (step S102). The CPU 71 determines whether or not the original G is inserted into the insertion roller 44. A determination is made based on the detection result of the insertion sensor 43 (step S103), and when the document G is not inserted (NO in step S103), the process returns to step S101 and the same processing is performed.

  When the insertion of the document G is detected in step S103, the CPU 71 drives the insertion roller drive motor 45 to rotationally drive the insertion roller 44 so that the document G is transported in the transport direction by the insertion roller 44, and the registration sensor 46 is driven. Checks whether the leading edge of the original G has been detected (step S105).

  In step S105, when the registration sensor 46 does not detect the leading edge of the document even after a predetermined time has elapsed (NO in step S105), the CPU 71 determines that a jam has occurred in the document G, and the operation unit 13 The document reading control process is terminated (step S106).

  When the registration sensor 46 detects the leading edge of the document in step S <b> 105, the CPU 71 detects a predetermined distance (the leading edge of the document G reaches the detection area of the skew sensor 47) after the registration sensor 46 detects the leading edge of the document. The insertion roller drive motor 45 is rotated by the distance) and the original G is conveyed by the insertion roller 44 (step S107). The two skew sensors 47 are caused to detect the positions of the leading edges of the original G, and the two skew sensors 47 The skew amount SU of the original G is calculated from the detection result of the leading edge position of the original G.

  That is, in the digital copying apparatus 1, the pixel position of the document G when the two skew sensors 47 detect the document G that is not skewed and whose front end surface is perpendicular to the document transport direction A is previously stored in the ROM. (Storage means) 72 and the like are stored as no-skew pixel positions in the CPU 72, and the CPU 71 determines that the conveyance-time pixel position detected by the skew sensor 47 in step S107 during conveyance of the original G is the no-skew in the ROM 72. The skew amount SU is calculated from the amount of deviation from the time pixel position.

  Then, the CPU 71 checks whether or not the calculated skew amount is equal to or less than a preset default value (set value) N (step S109). The predetermined value N is, for example, that even when the document front end surface is abutted against the stop teeth 48a of the stopper member 48 to correct the skew and the document is conveyed, the document end surface strongly hits the document side guide members 41a and 41b. A skew amount that does not cause a problem such as a jam or damage to the original G is preset and stored in the ROM 72 or the like.

  When the skew amount is smaller than the prescribed value N in step S109, the CPU 71 drives the guide drive motor 56 to rotate the pinion gear 42c in the clockwise direction indicated by the arrow in FIG. 6, thereby causing the pinion gear 42c and the rack gear 42a, The document side guide members 41a and 41b are moved by a predetermined amount in the direction away from the side end surface of the document G as shown by an arrow C in FIG. Even if the skew correction is performed by contact, the sheet is moved and retracted to a range where no trouble such as document breakage occurs (step S110).

  When the CPU 71 retracts the document side guide members 41 a and 41 b, with the stopper member 48 positioned at the stop position, the CPU 71 drives the insertion roller drive motor 45 to convey the document G by the insertion roller 44 and stops the stopper member 48. The skew correction is performed so that the leading end surface of the document is abutted against the stopper teeth 48 for a predetermined time and the leading end surface of the document G is aligned by the stopper portion 48a (step S111).

  In this case, the conveying force of the insertion roller 44 is such that the original G does not buckle even when the front end surface of the original is abutted against the stopper member 48, and the original side guide members 41a and 41b are retracted from the original end surface. The posture of the document G is changed according to the stopper member 48 without being restricted by the document side guide members 41a and 41b, and the skew correction is reliably performed based on the document leading edge.

  Further, since the document side guide members 41a and 41b are moved away from the side end surface of the document G, even when the document G is a long document, it is transported to the rear end by a slight skew at the front end of the document. Therefore, it is possible to prevent the skew from becoming large and the original side guide members 41a and 41b from being strongly contacted with each other, thereby preventing the original from being damaged.

  When the skew correction by the stopper unit 48 is completed, the CPU 71 drives the stopper switching solenoid 49 to rotate the stopper member 48 so that the stopper teeth 48 a are retracted to the retracted position where the stopper G 48 is retracted from the conveyance surface of the document G. Thereafter, the CPU 71 rotates the insertion roller drive motor 45 and the conveyance motor 57 to convey the document G in the document conveyance direction A by the insertion roller 44, the front conveyance roller 50, and the rear conveyance roller 52 (Step S112). The reading sensor unit 51 reads an image of the document G conveyed on the contact glass 51a, performs document reading processing to be output to the controller 70, and ends the document reading control processing (step S113).

  In step S109, as shown in FIG. 7, when the skew amount exceeds the specified value N, the CPU 71 determines that the document G is a document G whose document leading edge is non-right angle, and the stopper tooth 48 has a leading edge surface of the document G. Is pushed against the document side guide members 41a and 41b and the malfunction of the document G is likely to occur, and the stopper switching solenoid 49 is driven. As shown in FIG. 8, the stopper member 48 is rotated so that the stopper teeth 48a are retracted from the conveying surface of the document G to the retracted position, and the leading end surface of the document G is not brought into contact with the stopper portion 48a. The insertion roller drive motor 45 and the conveyance motor 57 are rotationally driven, and the document G is conveyed in the document conveyance direction A by the insertion roller 44, the front conveyance roller 50, and the rear conveyance roller 52. That (step S114).

  Therefore, the original G whose front end surface is not perpendicular to the original transport direction A is reversely moved with respect to the front end of the original, and the original G is guided along the original side guide members 41a and 41b with reference to the end surface on the original side. Even if the document G can be transported and the front end surface of the document is not perpendicular to the document transport direction A, the document G can be transported and the image of the document G can be transferred without stopping the document transport operation as in the prior art. Can be read.

  When the original G is conveyed on the contact glass 51a, the original reading unit 8 reads the image of the original G conveyed on the contact glass 51a and outputs it to the controller 70. The process is performed, and the document reading control process is terminated (step S113).

  In the above description, the case where the present invention is applied to the digital copying apparatus 1 has been described. However, the present invention can be similarly applied to an apparatus dedicated to an image reading apparatus such as a scanner apparatus.

  As described above, in the digital copying apparatus 1 of the present embodiment, the document reading unit 8 extends in the transport direction A of the document G that is transported to the image reading sensor unit (image reading unit) 51 that reads the image of the document G. Original side guide members (original side guide means) 41a and 41b that regulate the positions of the existing side end surfaces (both side end surfaces in the conveyance direction) and are movable in the document width direction B orthogonal to the conveyance direction, and the document side A guide moving mechanism (guide moving means) 42 that moves the guide members 41a and 41b in the document width direction A, and a leading edge position of the document G that is conveyed while the positions of the both end surfaces are regulated by the document side guide members 41a and 41b. A skew sensor (document leading edge detection means) 47 that detects at least two positions, and the skew amount of the document G based on the detection result of the skew sensor 47. A CPU (calculating means) 71 that is provided, and a stop position (front end abutting position) where the leading edge of the document G abuts and a retracted position through which the document G can pass are arranged on the downstream side of the skew sensor 47 in the document conveying direction. A movable stopper member (front end abutting member) 48, a stopper switching solenoid (front end abutting member moving means) 49 for moving the stopper member 48 to the stop position and the retracted position, and a skew amount calculated by the CPU 71 are obtained. If it is equal to or greater than a preset value, the document side guide members 41a and 41b are positioned to restrict the positions of the both end surfaces, and the stopper switching solenoid 49 moves the stopper member 48 to the retracted position. When the skew amount is smaller than the set value, the guide moving mechanism unit 42 causes the document side The id members 41a and 41b are moved away from the document side end surface, the stopper member 48 is positioned at the stop position by the stopper switching solenoid 49, and the leading end surface of the document G is abutted by the stopper member 48. And a CPU 71 for moving the stopper member 48 to the retracted position.

  Therefore, according to the skew amount (tilt amount) of the leading end surface of the document G, it can be set whether the leading end of the document is transported after being abutted against the stopper member 48 or transported in a side-restricted state. When the document side guide members 41a and 41b are conveyed after being abutted against each other, it is possible to prevent the document side end surface from hitting strongly and prevent the document from being damaged. With respect to the above, it is possible to suppress the occurrence of an abnormality such as document breakage while suppressing skew, and to efficiently carry the document.

  Further, in the digital copying apparatus 1 according to the present embodiment, the document reading unit 8 moves the position of both end surfaces in the transport direction of the document G to which the image of the document G is transported to the image reading sensor unit 51 with respect to the transport direction. A document side guide processing step for regulating the document side guide members 41a and 41b movable in the document width direction B orthogonal to each other, a guide movement processing step for moving the document side guide members 41a and 41b in the document width direction B, and a document Based on the document leading edge detection processing step that detects at least two leading edge positions of the document G that is conveyed while the positions of the side end surfaces of the side guide members 41a and 41b are regulated, and the detection result in the document leading edge detection processing step. A document processing step for calculating the skew amount of the document G, and the document transport from the document leading edge detection position in the document leading edge detection processing step. A front end abutting process that abuts the front end of the original G on a stopper member 48 that is disposed on the downstream side and is movable to a stop position (front end abutting position) where the original G abuts and a retracted position through which the original can pass. A step, a tip abutting member movement processing step for moving the stopper member 48 to the stop position and the retreat position, and a skew amount calculated in the calculation processing step is equal to or larger than a preset set value. The document side guide members 41a and 41b are positioned so as to restrict the positions of the both end surfaces, and the stopper member 48 is moved to the retracted position in the leading end abutting member moving processing step, and the skew amount is set as described above. If smaller than the value, the document side guide member 48 is separated from the document side end surface in the guide movement processing step. In addition, the stopper member 48 is positioned at the stop position in the leading end abutting member movement processing step, and the stopper member 48 is moved to the retracted position after the leading end surface of the document G hits the stopper member 48. An original reading method having a control processing step is executed.

  Therefore, according to the skew amount (tilt amount) of the leading end surface of the document G, it can be set whether the leading end of the document is transported after being abutted against the stopper member 48 or transported in a side-restricted state. When the document side guide members 41a and 41b are conveyed after being abutted against each other, it is possible to prevent the document side end surface from hitting strongly and prevent the document from being damaged. With respect to the above, it is possible to suppress the occurrence of an abnormality such as document breakage while suppressing skew, and to efficiently carry the document.

  Further, in the digital copying apparatus 1 of this embodiment, the document reading unit 8 uses a line sensor as the skew sensor 47.

  Accordingly, the skew amount of the original G can be detected with high accuracy and accurate skew control can be performed.

  Further, in the digital copying apparatus 1 of this embodiment, when the document reading unit 8 detects the leading edge position of the document G where the leading edge surface of the document G coincides with the document width direction B, the skew sensor 47 detects it. ROM (storage means) 72 for storing the pixel position of the image sensor, and the CPU 71 determines the amount of skew based on the pixel position at which the skew sensor 47 detects the leading edge position of the conveyed document G and the pixel position of the ROM 72. Calculated.

  Therefore, the skew amount of the original G can be obtained at low cost and with high accuracy, and accurate skew control can be performed.

  The invention made by the present inventor has been specifically described based on the preferred embodiments. However, the present invention is not limited to that described in the above embodiments, and various modifications can be made without departing from the scope of the invention. It goes without saying that it is possible.

DESCRIPTION OF SYMBOLS 1 Digital copying apparatus 2 Main body housing | casing 3 Paper feed part 4 Conveyance part 5 Image formation part 6 Fixing part 7 Paper discharge part 8 Document reading part 10 Manual feed tray 11 Document tray 12 Paper discharge tray 13 Operation part 14 Document paper discharge tray 21 Resist Roller 22 Photoconductor 23 Optical writing unit 30 Paper folding device 31 Connection unit 32 Ear folding unit 33 Bellows folding unit 34 Conveyance switching device 35 Reverse device 36 Rotating device 37 Tray 41a, 41b Document side guide member 42 Guide moving mechanism unit 42a, 42b Rack gear 42c Pinion gear 43 Document insertion detection sensor 44 Insertion roller 45 Insertion roller drive motor 46 Registration sensor 47 Skew sensor 48 Stopper member 48a Stop tooth 49 Stopper switching solenoid 50 Front transport roller 51 Image reading sensor section 51a Contour Tapering 52 after conveyance rollers 53 and 54 driven pulley 55 drives belt 70 Controller 71 CPU
72 ROM
73 RAM
74 Image processing unit 80 Image memory P Paper G Original

JP 7-319232 A JP-A-63-147743

Claims (5)

A document side guide unit that regulates the positions of both end surfaces of the document in the conveyance direction to be conveyed to an image reading unit that reads an image of the document, and that is movable in the document width direction orthogonal to the conveyance direction;
Guide moving means for moving the document side guide means in the document width direction;
A document leading edge detecting means for detecting at least two leading edge positions of the document conveyed while the positions of the both side end surfaces are regulated by the document side guide means;
Calculating means for calculating a skew amount of the original based on a detection result of the original leading edge detecting means;
A leading end abutting member disposed downstream of the document leading end detection means and movable between a leading end abutting position where the leading end of the document abuts and a retracted position through which the document can pass;
Tip abutting member moving means for moving the tip abutting member to the tip abutting position and the retracted position;
If the skew amount calculated by the calculating means is greater than or equal to a preset value, the document side guide means is positioned at a position that regulates the position of the both end faces, and the leading end abutting member moving means When the leading edge abutting member is moved to the retracted position and the skew amount is smaller than the set value, the guide side moving means moves the document side guide means away from the document side end surface, and Control that causes the abutting member moving means to position the leading edge abutting member at the leading edge abutting position, and moves the leading edge abutting member to the retracted position after the leading edge surface of the document abuts against the leading edge abutting member. Means,
A document reading apparatus comprising: The document leading edge detection means includes:
The document reading device according to claim 1, wherein the document reading device is a line sensor. The document reading device includes:
Storage means for storing pixel positions when the document leading edge detection means detects at least two document leading edge positions where the document leading edge surface coincides with the document width direction;
The calculating means includes
3. The document reading according to claim 2, wherein the skew amount is calculated based on a pixel position detected by the document leading edge detection unit and a pixel position of the storage unit. apparatus. An image forming apparatus in which an image forming unit forms an image on an image forming medium by a predetermined image forming method based on image data obtained by reading an image of a document by a document reading unit.
An image forming apparatus comprising the document reading device according to claim 1 as the document reading unit. Document side guide processing step for regulating the positions of both end faces in the conveyance direction of the document conveyed to the image reading means for reading the image of the document by document side guide means movable in the document width direction orthogonal to the conveyance direction. When,
A guide movement processing step for moving the document side guide means in the document width direction;
A document leading edge detection processing step for detecting at least two leading edge positions of the document conveyed while the positions of the both side end surfaces are regulated by the document side guide means;
A calculation processing step for calculating a skew amount of the document based on a detection result in the document leading edge detection processing step;
A front end that is disposed downstream of the original front end detection position in the original front end detection processing step and that can move between a front end abutting position where the front end of the original abuts and a retracted position through which the original can pass. A leading edge abutting step for abutting the leading edge of the document against the abutting member;
A tip abutting member movement processing step for moving the tip abutting member to the tip abutting position and the retracted position;
When the skew amount calculated in the calculation processing step is greater than or equal to a preset value, the document side guide means is positioned at a position that restricts the positions of the both end surfaces, and the leading end abutting member moving process is performed. In step, the leading end abutting member is moved to the retracted position, and when the skew amount is smaller than the set value, the document side guide means is moved away from the document side end surface in the guide moving processing step. In addition, the front end abutting member is positioned at the front end abutting position in the front end abutting member moving processing step, and the front end abutting member is retracted after the front end surface of the document abuts against the front end abutting member. A control processing step to move to a position;
A document reading method characterized by comprising:

Images