JP5963369B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus including a charging device.

  2. Description of the Related Art Conventionally, an image forming apparatus (copier) provided with a charging device is known. Such an image forming apparatus is installed in a store, a public facility, or the like, and charges a user for a predetermined original copy fee each time an original is copied (see, for example, Patent Document 1). .

  For example, in an image forming apparatus provided with a charging device, an image reading unit and a printing unit on which a document transport unit is mounted are provided as a copy job execution unit. When the copy job is executed, the document transport unit transports the document to the reading position of the image reading unit, and the image reading unit reads the document passing through the reading position. The printing unit prints the document image read by the image reading unit on paper and discharges it to the discharge tray. The billing device charges the user for a copy fee of the document every time the printing unit performs printing (each time printed paper is discharged to the discharge tray).

JP 2000-347533 A

  For example, in an image forming apparatus including a charging device, in parallel with reading of a document by an image reading unit (conveying a document by a document conveying unit), printing of a document image read by the image reading unit on a sheet is performed on a printing unit. Let it be done. This shortens the time from the start to the end of the copy job, which is convenient for the user.

  Here, the document transport unit stops transporting a document when a document transport error such as a jam occurs during transport of the document. At this time, if the trailing edge of the document has already passed the reading position, reading of the document by the image reading unit has been completed, and thus the sheet on which the document image has been printed normally is discharged to the discharge tray. On the other hand, if the trailing edge of the document has not passed the reading position, reading of the document by the image reading unit has not been completed, and thus the paper on which the document image is not normally printed is discharged to the discharge tray. . Therefore, if the user is charged for the copy fee of the document that was being transported when the document transport error occurred, it will be disadvantageous to the user. For this reason, when a document transport error occurs during the execution of a copy job, it is general that the user is not charged for the copy fee of the document transported when the document transport error occurs.

  However, some users attempt to avoid charging by intentionally generating a document transport error at the timing when the trailing edge of the document passes the reading position (timing when the image reading unit finishes reading the document). There is a case. If the image forming apparatus continues to be used by an unauthorized user who wants to avoid such charges, a copy fee for the original cannot be collected even though a sheet on which the original image is normally printed is acquired. Therefore, it is not convenient for the installer of the image forming apparatus (the person who collects the copy fee of the original).

  The present invention has been made to solve the above-described problems, and in the configuration in which the copy unit charges a copy fee each time printing is performed, it is possible to prevent image evasion from being repeated repeatedly. An object is to provide an apparatus.

  In order to achieve the above object, an image forming apparatus according to the present invention is a chargeable image forming apparatus capable of carrying out a copy job for conveying a document, reading the document being conveyed, and printing an image of the read document on paper. An original reading unit, an original conveying unit having an original conveying path passing through the reading stage, and conveying an original along the original conveying path, an image reading unit for reading an original on the reading stage, and an image reading A first mode in which a document image read by the image reading unit is printed on a sheet in parallel with the reading of the document by the image reading unit, and the image reading unit reads the document read by the image reading unit after the document is discharged from the document conveyance path. A document transport error occurs when the document transport unit transports a document and a printing unit that executes a copy job in any one of the second modes in which printing of the original document image onto paper is started Error detection unit that stops the conveyance of the document by the document conveyance unit, and when the printing unit performs printing, the copy fee for the document is charged and an error occurs. When the detection unit detects the occurrence of a document conveyance error, the charging unit includes a charging device that does not charge for the copy fee of the document conveyed when the document conveyance error is detected. The error occurrence detection unit detects a document transport error when executing a copy job in the first mode, and detects a document transport error by a specific error that is predetermined by the user. If the error detection unit determines that the document transport error is a specific error, the printing unit starts a copy job that starts after the error detection unit detects the occurrence of the document transport error. Is executed in the second mode.

  When the job mode of the copy job is the first mode, the original image read by the image reading unit is printed on the paper in parallel with the reading of the original by the image reading unit. For this reason, if a document transport error occurs at the timing when the document reading by the image reading unit is completed, the document copy fee is not charged even though the document image is normally printed on the paper. Therefore, if the document transport error that occurred during the execution of the copy job in the first mode is a specific error (an error that is predetermined as a result that can be intentionally generated by the user), the document transport error can be avoided. It may have been intentionally generated by an unauthorized user.

  On the other hand, when the job mode of the copy job is the second mode, printing of the original image read by the image reading unit on the paper starts after the original read by the image reading unit is discharged from the original conveyance path. Is done. In the second mode, the time taken from the start to the end of the copy job is longer than in the first mode. However, even if a document transport error is intentionally generated by an unauthorized user who wants to avoid charging, printing of the document image transported at the time of the document transport error on the paper has not started. Can be prevented.

  Therefore, in the present invention, when a document transport error occurs during execution of a copy job in the first mode, the document transport error is a specific error (an error that is predetermined as an error that can be intentionally generated by the user). If there is, the copy job started thereafter is executed in the second mode. As a result, it is possible to prevent repeated evasion of charges.

  According to the present invention, in the configuration in which the copy unit charges the copy fee each time printing is performed, it is possible to prevent the charge escape from being repeated repeatedly.

1 is a schematic view of an image forming apparatus according to an embodiment of the present invention. Schematic diagram of an image reading unit (original transport unit) provided in the image forming apparatus shown in FIG. FIG. 2 is a block diagram for explaining a hardware configuration of the image forming apparatus shown in FIG. FIG. 2 is a block diagram for explaining a hardware configuration of the image forming apparatus (image reading unit) shown in FIG. 1. 1 is a flowchart for explaining the flow of control when the job mode of a copy job is changed from the first mode to the second mode in the image forming apparatus shown in FIG. Flowchart for explaining the flow of control when the job mode of a copy job is returned to the first mode in the image forming apparatus shown in FIG. Flowchart for explaining the flow of control when the job mode of a copy job is returned to the first mode in the image forming apparatus shown in FIG. Flowchart for explaining the flow of control when the job mode of a copy job is returned to the first mode in the image forming apparatus shown in FIG.

(Overall configuration of image forming apparatus)
As shown in FIG. 1, an image forming apparatus 100 according to the present embodiment includes an image reading unit 2 to which a document conveying unit 1 is attached, a printing unit 3 (a paper feeding unit 4, a paper conveying unit 5, an image forming unit 6, and an image forming unit 6. A fixing unit 7) and an operation panel 8 are provided.

  As shown in FIG. 2, the image reading unit 2 on which the document conveying unit 1 is mounted has a reading table 20 on which a contact glass 20a for conveying reading and a contact glass 20b for placing reading are fitted. The image reading unit 2 can perform conveyance reading for reading the document D passing on the contact glass 20a and placement reading for reading the document D placed on the contact glass 20b.

  The document transport unit 1 is supported on the reading table 20 so as to be openable and closable (rotatable). The document transport unit 1 transports the document D onto the contact glass 20a. Specifically, the document transport unit 1 includes a document set tray 11, a document discharge tray 12, a paper feed unit 13, and a document transport unit 14. The document transport unit 1 is provided with a document transport path 10 for transporting the document D.

  The document setting tray 11 is a tray on which the document D is set, and is disposed on one end side of the document conveyance path 10. The document discharge tray 12 is a tray from which the document D that has been read is discharged, and is disposed on the other end side of the document conveyance path 10. At the time of conveyance reading, the document D set on the document setting tray 11 is supplied to the document conveyance path 10, conveyed along the document conveyance path 10, and finally discharged to the document discharge tray 12. Here, the reading position RP (position on the contact glass 20 a) at the time of conveyance reading is a position in the middle of the conveyance path of the document D conveyed along the document conveyance path 10. That is, when the document D is transported along the document transport path 10, the document D passes over the contact glass 20a. As a result, the image reading unit 2 reads one side of the original D (the side facing upward when the original D is set on the original setting tray 11).

  The paper feed unit 13 is provided on the most upstream side of the document conveyance path 10. The paper feed unit 13 includes a pickup roller 13a, a paper feed belt 13b, and a separation roller 13c. The pickup roller 13 a rotates in contact with the document D set on the document setting tray 11. As a result, the document D is pulled out from the document set tray 11 and enters the paper feed nip. The paper feed belt 13b is stretched by a drive roller 13d and a driven roller 13e, and forms a paper feed nip with the separation roller 13c. The paper feed belt 13b is rotated by the rotation of the driving roller 13d, and supplies the document D that has entered the paper feed nip to the document transport path 10. The separation roller 13c rotates so that the document D advances in the direction opposite to the document transport direction. For this reason, even if a plurality of documents D are pulled out from the document set tray 11, the plurality of documents D are separated one by one.

  The document transport unit 14 includes a plurality of transport roller pairs 14 a to 14 e arranged along the document transport path 10, and transports the document D along the document transport path 10. The conveyance roller pairs 14 a to 14 e are arranged in this order from the upstream side of the document conveyance path 10. Among the transport roller pairs 14a to 14e, the transport roller pair 14a closest to the paper feeding unit 13 is the registration roller pair 14a. The registration roller pair 14a temporarily stops the progress of the document D, bends the document D, and corrects the skew of the document D.

  The mechanism unit including the paper feeding unit 13 and the document conveying unit 14 is covered with an exterior cover. The upper part of the exterior cover can be opened and closed. When the openable / closable part of the exterior cover (hereinafter referred to as “open / close cover CV”) is opened, the document conveyance path 10 is exposed. For this reason, if the open / close cover CV is opened when a jam occurs, the jam processing can be easily performed. Although not shown in FIG. 2, the document transport unit 1 is provided with a cover opening / closing detection sensor CS (see FIG. 4) for detecting opening / closing of the opening / closing cover CV.

  Further, the document transport unit 1 is provided with a plurality of document detection sensors DS1 to DS4 for detecting the presence or absence (arrival and passage of the trailing edge) of the document D at a plurality of detection positions DP1 to DP4 in the document transport path 10. Yes. Document detection sensors DS1 to DS4 are, for example, reflective optical sensors having a light emitting unit that emits light toward a detection target and a light receiving unit that receives reflected light from the detection target. Each output of the document detection sensors DS1 to DS4 varies depending on whether or not the document D exists at the corresponding detection position DP.

  The image reading unit 2 includes a lamp 21, an image sensor 22, a mirror 23 and a lens 24, and optically reads the document D on the reading table 20. Each member of the image reading unit 2 is disposed in a frame constituting the reading table 20.

  The lamp 21 has a plurality of LED elements, and generates light that irradiates the document D. Although not shown, the plurality of LED elements are arranged in a line in the main scanning direction (direction perpendicular to the paper surface of FIG. 2) which is the reading line direction. A cold cathode tube or the like may be used as the lamp 21. The lamp 21 irradiates the contact glass 20a with light when reading the document D passing over the contact glass 20a (the light transmitted through the contact glass 20a irradiates the document D). On the other hand, when reading the document D placed on the contact glass 20b, the lamp 21 emits light toward the contact glass 20b (the light transmitted through the contact glass 20b irradiates the document D). The reflected light reflected by the document D is reflected by the mirror 23 and guided to the lens 24. The lens 24 collects the reflected light.

  The image sensor 22 reads the document D line by line by receiving the reflected light reflected by the document D (light collected by the lens 24). The image sensor 22 includes a CCD having a plurality of photoelectric conversion elements arranged in a line in the main scanning direction. When receiving reflected light, the image sensor 22 performs photoelectric conversion for each pixel in units of lines and accumulates electric charges. Then, the image sensor 22 outputs an analog signal corresponding to the accumulated charge. That is, the analog output for each pixel of the image sensor 22 varies according to the amount of reflected light.

  The lamp 21 and the mirror 23 are held by a holding member 26 that can move in the sub-scanning direction orthogonal to the main scanning direction. The holding member 26 is connected to one end of the wire 27. The other end of the wire 27 is connected to a winding drum 28 that winds the wire 27 by rotating. Accordingly, the holding member 26 moves in the sub-scanning direction by rotating the winding drum 28, and the lamp 21 and the mirror 23 move in the sub-scanning direction together with the holding member 26. Note that a plurality of wires 27 are connected to the holding member 26, and the plurality of wires 27 are wound around. However, in FIG. 2, only one wire 27 is shown for convenience.

  During conveyance reading, the holding member 26 moves below the contact glass 20a and stops. Thereafter, the document transport unit 1 transports the document D onto the contact glass 20a. At this time, the lamp 21 irradiates light on the document D passing over the contact glass 20a, and the image sensor 22 continuously and repeatedly performs photoelectric conversion of the reflected light reflected by the document D. As a result, one side of the document D (the surface facing upward when the document D is set on the document set tray 11) is read line by line.

  On the other hand, at the time of placement reading, the holding member 26 moves in the sub-scanning direction (direction from left to right as viewed from the front). While the holding member 26 is moving in the sub-scanning direction, the lamp 21 irradiates the document D placed on the contact glass 20b, and the reflected light reflected by the document D is photoelectrically reflected. The conversion is continuously repeated by the image sensor 22. As a result, the surface of the document D facing the contact glass 20b is read line by line.

  The reading table 20 is provided with a unit opening / closing detection sensor US for detecting opening / closing of the document conveying unit 1 with respect to the reading table 20. The unit open / close detection sensor US moves, for example, in the vertical direction between the light emitting unit, the light receiving unit, and the light emitting unit and the light receiving unit, and toward the region on the reading table 20 (the region on the document transport unit 1 side). An optical sensor having a protruding actuator. The unit opening / closing detection sensor US is disposed in the vicinity of a hinge (not shown) that supports the document conveying unit 1 so as to be opened and closed. When the inclination of the document conveying unit 1 becomes smaller than a predetermined angle, the actuator of the unit open / close detection sensor US is pressed by the document conveying unit 1 and moves downward to block the optical path between the light emitting unit and the light receiving unit (or ,Open. On the other hand, the actuator of the unit opening / closing detection sensor US moves upward when the inclination of the document conveying unit 1 is larger than a predetermined angle, by releasing the pressing by the document conveying unit 1, and between the light emitting unit and the light receiving unit. Open (or block) the optical path between them.

  The document transport unit 1 is provided with a CIS unit 15 for reading the other surface opposite to the one surface of the document D (the surface directed downward when the document D is set on the document setting tray 11). ing. The CIS unit 15 is disposed at a predetermined location along the document conveyance path 10. As a result, both sides of the document D can be read simultaneously.

  Returning to FIG. 1, the printing unit 3 includes a paper feeding unit 4, a paper transporting unit 5, an image forming unit 6, and a fixing unit 7. Then, the printing unit 3 conveys the paper P along the paper conveyance path 30, prints an image based on the image data obtained by reading by the image reading unit 2 on the paper P, and outputs it (copy job).

  The paper feed unit 4 supplies the paper P stored in the paper cassette 41 to the paper transport path 30. The paper feed unit 4 includes a pickup roller 42 and a paper feed roller pair 43. The pickup roller 42 sends the paper P stored in the paper cassette 41 to the paper feed nip of the paper feed roller pair 43, and the paper feed roller pair 43 supplies the paper P that has entered the paper feed nip to the paper transport path 30. .

  The paper transport unit 5 transports the paper P supplied to the paper transport path 30 in the order of the transfer nip and the fixing nip, and discharges it to the discharge tray 51. The paper transport unit 5 includes a plurality of transport roller pairs 52 for transporting the paper P along the paper transport path 30. One conveyance roller pair 52 among the plurality of conveyance roller pairs 52 is a registration roller pair 53. The registration roller pair 53 waits for the paper P in front of the transfer nip, and sends the paper P to the transfer nip in time.

  The image forming unit 6 forms a toner image based on the image data, and transfers the toner image onto the paper P. The image forming unit 6 includes a photosensitive drum 61, a charging device 62, an exposure device 63, a developing device 64, a transfer roller 65, and a cleaning device 66.

  At the time of image formation, the photosensitive drum 61 rotates and the charging device 62 charges the surface of the photosensitive drum 61 to a predetermined potential. The exposure device 63 scans and exposes the surface of the photosensitive drum 61 to form an electrostatic latent image on the surface of the photosensitive drum 61. The developing device 64 supplies toner to the electrostatic latent image formed on the surface of the photosensitive drum 61 and develops it.

  The transfer roller 65 is in pressure contact with the surface of the photosensitive drum 61 and forms a transfer nip with the photosensitive drum 61. In this state, the registration roller pair 53 measures the timing and causes the paper P to enter the transfer nip. As a result, the toner image on the surface of the photosensitive drum 61 is transferred onto the paper P. When the transfer of the toner image onto the paper P is completed, the cleaning device 66 removes the toner remaining on the surface of the photosensitive drum 61.

  The fixing unit 7 heats and pressurizes the toner image transferred onto the paper P and fixes the toner image. The fixing unit 7 includes a heating roller 71 and a pressure roller 72. The heating roller 71 has a built-in heat source. The pressure roller 72 is in pressure contact with the heating roller 71 and forms a fixing nip with the heating roller 71. The paper P on which the toner image is transferred is heated and pressurized by passing through the fixing nip.

  Further, the printing unit 3 is provided with a plurality of paper detection sensors for detecting the presence or absence (arrival and passage of the trailing edge) of the paper P at a plurality of detection positions of the paper conveyance path 30. The plurality of paper detection sensors are, for example, reflective optical sensors having a light emitting unit that emits light toward a detection target and a light receiving unit that receives reflected light from the detection target. Each output of the plurality of paper detection sensors varies depending on whether the paper P is present at the corresponding detection position or not. A detection position DP10 of a predetermined paper detection sensor DS10 among the plurality of paper detection sensors is a position downstream of the fixing nip in the paper transport direction (a position immediately before reaching the discharge tray 51). FIG. 1 shows only a predetermined paper detection sensor DS10 among a plurality of paper detection sensors for simplification of the drawing.

  The operation panel 8 includes a liquid crystal display unit 81 with a touch panel. The liquid crystal display unit 81 displays soft keys and messages for accepting various settings from the user. Further, the operation panel 8 is provided with hard keys such as a numeric keypad 82 and a start key 83.

  Here, the image forming apparatus 100 includes a charging device 9 connected via a cable CB, and charges a copy fee of the document D to a user who performs copying with the image forming apparatus 100. For example, the billing device 9 is a coin vendor and includes a money insertion slot 91, an amount display unit 92, and a money return slot 93. The charging device 9 may be a prepaid card method.

  When the money is inserted into the money insertion slot 91, the billing device 9 displays the amount of money on the amount display unit 92. When the copy job is executed, the charging device 9 deducts the copy fee of the document D from the input amount each time the printing unit 3 performs printing, and displays the deducted amount on the amount display unit 92 (printing unit 3 The amount of money displayed in the money amount display section 92 decreases each time printing is performed). After the copy job is completed, the charging device 9 returns the balance from the money return port 93.

(Hardware configuration of image forming apparatus)
As shown in FIG. 3, the image forming apparatus 100 includes a main control unit 110 that controls the entire apparatus and controls the printing operation of the printing unit 3. The main control unit 110 includes a main CPU 111, an image processing unit 112, a time measuring unit 113, and a storage unit 114. The image processing unit 112 includes an ASIC dedicated to image processing, and performs image processing (enlargement / reduction, density conversion, data format conversion, etc.) on the image data. The timer 113 is an RTC (real-time clock) and measures time. The storage unit 114 includes a ROM and a RAM, and stores a control program and data.

  The main controller 110 is connected to a plurality of paper detection sensors including a paper detection sensor DS10. The main control unit 110 detects the presence or absence (arrival and rear end passage) of the paper P at a plurality of detection positions including the detection position DP10 of the paper transport path 30 based on the outputs of the plurality of paper detection sensors. It is determined whether or not a paper transport error has occurred in the transport path 30 and the transport timing of the paper P is measured.

  Further, a scan control unit 210 is connected to the main control unit 110. As shown in FIG. 4, the scan control unit 210 includes a CPU 211 and a storage unit 212. The scan control unit 210 receives instructions from the main control unit 110 and controls the document conveyance operation of the document conveyance unit 1 and the image reading operation of the image reading unit 2. The scan control unit 210 corresponds to the “error occurrence detection unit” of the present invention.

  Specifically, the scan control unit 210 is connected to a transport motor M1 for rotating the rollers of the paper feed unit 13 and the document transport unit 14, and appropriately controls the rollers of the paper feed unit 13 and the document transport unit 14. Rotate. The scan control unit 210 is connected to a winding motor M2 for rotating the winding drum 28, and appropriately rotates the winding drum 28. That is, the scan control unit 210 moves the holding member 26 in the sub-scanning direction and controls the irradiation position of the lamp 21.

  The scan control unit 210 is connected to the lamp 21 and the image sensor 22 and controls each operation of the lamp 21 and the image sensor 22. Further, the scan control unit 210 is connected to the analog processing unit 221, the correction unit 222, and the image memory 223 in order to process the analog output of the image sensor 22. The analog processing unit 221 includes an amplifier circuit, an A / D conversion circuit, and the like. The analog processing unit 221 amplifies the analog output of the image sensor 22, converts it into digital image data, and outputs the digital image data. The correction unit 222 performs correction such as shading correction. The image memory 223 accumulates image data and transfers it to the main control unit 110 (image processing unit 112).

  Receiving the image data, the main control unit 110 (image processing unit 112) performs image processing on the image data and generates image data for exposure (data for turning on and off the light emitting elements of the exposure device 63). . Then, the main control unit 110 outputs the image data for exposure to the printing unit 3.

  Further, the scan control unit 210 is connected to the document detection sensors DS1 to DS4, and based on the outputs of the document detection sensors DS1 to DS4, the presence or absence of the document D (arrival and trailing edge) at the detection positions DP1 to DP4 of the document conveyance path 10 is detected. ) Is detected. Then, the scan control unit 210 determines whether or not a document transport error (jam) has occurred in the document transport path 10 and measures the transport timing of the document D.

  Further, the scan control unit 210 is connected to the unit opening / closing detection sensor US and the cover opening / closing detection sensor CS. Then, the scan control unit 210 detects opening / closing of the document transport unit 1 based on the output of the unit opening / closing detection sensor US, and detects opening / closing of the opening / closing cover CV based on the output of the cover opening / closing detection sensor CS.

  Returning to FIG. 3, the main control unit 110 is connected to the operation panel 8, controls the display operation of the operation panel 8, and detects an operation performed by the user on the operation panel 8. For example, the main control unit 110 displays a message for requesting the insertion of money on the liquid crystal display unit 81 if money is not inserted in the charging device 9. A setting screen is displayed on the liquid crystal display unit 81 (copying with the image forming apparatus 100 becomes possible). Then, when money is inserted into the charging apparatus 9 and the start key 83 is pressed, the main control unit 110 recognizes the pressing operation as a copy job execution instruction. Alternatively, the main control unit 110 always displays a setting screen related to the copy job on the liquid crystal display unit 81, and requests the insertion of money when the start key 83 is pressed in a state where no money is inserted in the charging device 9. The message is displayed on the liquid crystal display unit 81.

  The main control unit 110 is connected to the billing apparatus 9 via the I / F unit 120 so as to be communicable. Then, when money is inserted, the charging device 9 notifies the main control unit 110 of information (money receipt information) that money has been inserted. The main control unit 110 that has received the money receipt information notification causes the copy job to be executed when the start key 83 is pressed.

  When the printing unit 3 completes printing for one sheet at the time of execution of a copy job, the main control unit 110 sends information (copy completion information) to the effect that copying of one document D has been completed. 9 is notified. For example, the main control unit 110 detects whether the trailing edge of the paper P has passed through the detection position DP10 based on the output of the paper detection sensor DS10. When the main control unit 110 detects the passage of the trailing edge of the paper P at the detection position DP10, the main control unit 110 determines that printing for one sheet by the printing unit 3 has been completed, and notifies the charging device 9 of copy completion information. Receiving the notification of the copy completion information, the charging device 9 charges a copy fee for one original document D.

(Job mode for copy jobs)
The main control unit 110 sets one of the first mode and the second mode as a copy job execution mode. When the first mode is set, the printing unit 3 prints the image of the document D read by the image reading unit 2 on the paper P in parallel with the reading of the document D by the image reading unit 2. When the second mode is set, the printing unit 3 discharges the document D read by the image reading unit 2 from the document conveyance path 10 and then onto the sheet P of the image of the document D read by the image reading unit 2. Start printing. Hereinafter, the operation at the time of executing the copy job will be described in detail.

  First, when money is inserted into the billing apparatus 9 and the operation panel 8 receives an instruction to execute a copy job, the main control unit 110 instructs the scan control unit 210 to execute a copy job (reading the original D).

  When the scan control unit 210 receives an instruction to execute a copy job (reading of the document D) from the main control unit 110, the scan control unit 210 causes the sheet feeding unit 13 to perform a sheet feeding operation and causes the document conveying unit 14 to perform a conveying operation. That is, the paper feed unit 13 supplies the document D set on the document set tray 11 to the document transport path 10. The document transport unit 14 transports the document D along the document transport path 10.

  When the document D supplied from the document setting tray 11 to the document transport path 10 is transported along the document transport path 10 and the document D reaches the detection position DP3 (see FIG. 2), the output level of the document detection sensor DS3 is increased. Since it fluctuates (becomes a level indicating that the document D exists), the scan control unit 210 detects the arrival of the document D at the detection position DP3. Then, the scan control unit 210 starts reading of the document D by the image reading unit 2 at the timing when the document D reaches the reading position RP (see FIG. 2). Thereafter, the scan control unit 210 ends the reading of the document D by the image reading unit 2 at a timing when the trailing edge of the document D completely passes through the reading position RP. Note that the reading start timing by the image reading unit 2 can be obtained based on the distance between the detection position DP3 and the reading position RP and the document conveyance speed (the point in time when the leading edge of the document D is detected at the detection position DP3). And the timing at which the leading edge of the document D reaches the reading position RP is measured). Further, the end timing of reading by the image reading unit 2 can be obtained based on the length of the document D and the document conveyance speed. Alternatively, the reading end timing by the image reading unit 2 can be obtained based on the distance between the detection position DP3 and the reading position RP and the document conveyance speed (the time point when the passage of the trailing edge of the document D is detected at the detection position DP3). The timing at which the trailing edge of the document D passes through the reading position RP as a base point is measured).

  When the document D reaches the detection position DP4 (see FIG. 2) after the image reading unit 2 starts reading the document D, the output level of the document detection sensor DS4 varies (to a level indicating that the document D is present). Therefore, the scan control unit 210 detects the arrival of the document D at the detection position DP4. Subsequently, when the trailing edge of the document D passes the detection position DP4, the output level of the document detection sensor DS4 returns to the original level (a level indicating that there is no document D), so that the scan control unit 210 at the detection position DP4. The passage of the trailing edge of the document D is detected. When the scan control unit 210 detects passage of the trailing edge of the document D at the detection position DP4, the scan control unit 210 determines that the document D is discharged from the document transport path 10 (discharged to the document discharge tray 12).

  Here, in the first mode, the main control unit 110 starts printing by the printing unit 3 while the image reading unit 2 is reading the document D. Thereby, in parallel with the reading of the document D by the image reading unit 2, the image of the document D read by the image reading unit 2 is printed on the paper P. On the other hand, in the second mode, after the trailing edge of the document D passes the detection position DP4, that is, after the document D read by the image reading unit 2 is discharged from the document transport path 10, the main control unit 110 Then, printing by the printing unit 3 is started.

  When the paper P reaches the detection position DP10 (see FIG. 1) after the printing by the printing unit 3 is started, the output level of the paper detection sensor DS10 changes (becomes a level indicating that the paper P is present). The main control unit 110 detects the arrival of the paper P at the detection position DP10. Subsequently, when the trailing edge of the paper P passes the detection position DP10, the output level of the paper detection sensor DS10 returns to the original level (a level indicating that there is no paper P), so the main control unit 110 at the detection position DP10. The passage of the trailing edge of the paper P is detected. Then, when the main control unit 110 detects the passage of the rear end of the paper P at the detection position DP10, the main control unit 110 determines that printing for one sheet is completed.

  Thereafter, the main control unit 110 notifies the charging apparatus 9 of copy completion information. Upon receiving this notification, the billing device 9 charges a copy fee for one original document D.

(Detection of document transport error)
The scan control unit 210 detects the arrival of the document D and the passage of the trailing edge at the detection positions DP1 to DP4 (see FIG. 2) at the time of executing the copy job, and determines whether a document conveyance error (jam) has occurred. For example, the scan control unit 210 starts timing after detecting the arrival of the document D at a certain detection position (first detection position) among the detection positions DP1 to DP4. Then, the scan control unit 210 detects the detection position (the second detection position and the second detection position) on the downstream side in the document transport direction from the first detection position when a predetermined time has elapsed since the arrival of the document D was detected at the first detection position. If the arrival of the document D cannot be detected in (Yes), it is determined that a document transport error has occurred. The predetermined time in this case is a scheduled time required for the document D to travel between the first detection position and the second detection position, and the distance between the first detection position and the second detection position, and This is a time that can be calculated in advance based on the document conveyance speed.

  Alternatively, the scan sending control unit 210 detects the passage of the trailing edge of the document D at the same detection position even after a predetermined time has elapsed after detecting the arrival of the document D at a detection position among the detection positions DP1 to DP4. If not, it is determined that a document transport error has occurred. The predetermined time in this case is a scheduled time required for the trailing edge of the document D to pass through the same detection position after the document D reaches a certain detection position, and the length of the document D and the document conveyance speed. Is a time that can be calculated in advance.

  Further, the scan control unit 210 detects the opening / closing of the document conveyance unit 1 based on the output of the unit opening / closing detection sensor US when a copy job is executed. The scan control unit 210 also determines that a document transport error has occurred when it is detected that the document transport unit 1 is open when the copy job is executed. Furthermore, the scan control unit 210 detects the opening / closing of the opening / closing cover CV based on the output of the cover opening / closing sensor CS when executing a copy job. The scan control unit 210 also determines that a document conveyance error has occurred when it is detected that the open / close cover CV is open during the execution of the copy job.

  When the scan control unit 210 detects the occurrence of a document conveyance error during the execution of a copy job, the scan control unit 210 stops the document conveyance operation of the document conveyance unit 1 and stops the image reading operation of the image reading unit 2. Further, the scan control unit 210 notifies the main control unit 110 that a document transport error has occurred.

  When receiving a document conveyance error occurrence notification from the scan control unit 210, the main control unit 110 instructs the operation panel 8 to notify that a document conveyance error has occurred. For example, the operation panel 8 displays a message that a document transport error has occurred, a message that prompts the user to reset the document D, and the like. Further, the main control unit 110 puts a copy job in which a document transport error has occurred into a stopped state.

  After the copy job in which the document transport error has occurred is stopped, the main control unit 110 determines whether or not a cancel operation for canceling the copy job in which the document transport error has occurred has been performed by the user. For example, a cancel key 84 for canceling a copy job is provided on the operation panel 8, and the main control unit 110 determines that a cancel operation has been performed when the pressing of the cancel key 84 is detected. When a cancel operation is performed on the operation panel 8, the main control unit 110 cancels the copy job in which the document conveyance error has occurred and returns it to a state where the copy job can be executed (a copy job execution instruction is issued). The reception is performed on the operation panel 8). As a result, the user can resume the copy job.

(Copy job mode setting)
The main control unit 110 sets the first mode of the first mode and the second mode as a default mode (usually set to the first mode). The reason is to shorten the time taken from the start to the end of the copy job and improve the convenience for the user.

  However, if the first mode is set, reading of the document D by the image reading unit 2 is started, and after printing by the printing unit 3 is started, the rear end of the document D is at the reading position RP (see FIG. 2). A document transport error may occur before the document passes completely. When a document transport error occurs at such timing, a sheet P on which only an image of a portion of the document D that has passed the reading position is printed (paper P on which the image of the document D is printed halfway) is output. Will be. For this reason, if the copy fee for the document D that was being transported when the document transport error occurred is charged, this is disadvantageous to the user.

  Therefore, when the main control unit 110 receives a document conveyance error notification from the scan control unit 210 during execution of the copy job, the copy is completed even if the trailing edge of the paper P passes the detection position DP10 (see FIG. 1). The information is not notified to the charging device 9. That is, the billing device 9 does not charge for the copy fee of the document D that was transported when the document transport error occurred.

  However, if a document transport error occurs during the execution of a copy job in the first mode, if the trailing edge of the document D has already passed the reading position RP, the copy fee for the document D is not charged, but the document D The paper P on which the image is normally printed is output. By utilizing this point, some users may intentionally generate a document transport error at the timing when the trailing edge of the document D passes the reading position RP, and try to avoid the charge for copying the document D. . Such illegal evasion of billing may be repeated continuously. Therefore, it is inconvenient for the installer of the image forming apparatus 100 (the person who collects the copy fee of the document D).

  Therefore, in the present embodiment, when a document transport error occurs during execution of a copy job in the first mode, if the document transport error is an error that can be intentionally generated by the user, the copy job to be started next. The job mode is changed to the second mode and executed. In the second mode, the printing unit 3 prints the image of the original D read by the image reading unit 2 on the paper P after the original D read by the image reading unit 2 is discharged from the original conveyance path 10. To start. Therefore, even if a document transport error occurs during the execution of the copy job in the second mode, printing of the image of the document D transported at the time of the document transport error on the paper P has not been started, and charging is avoided. Can not do. Hereinafter, the mode change operation of the copy job will be described in detail.

  First, the scan control unit 110 detects whether or not a document conveyance error has occurred during execution of a copy job in the first mode. When the scan control unit 110 detects the occurrence of a document conveyance error, the scan control unit 110 determines whether or not the document conveyance error is a specific error that is predetermined as being intentionally generated by the user.

  Here, in the configuration in which the change from the closed state to the open state of the document transport unit 1 or the opening / closing cover CV is detected as the occurrence of a document transport error, the document is intentionally copied at the timing when the trailing edge of the document D passes the reading position RP. A transport error is likely to occur (the document transport unit 1 and the opening / closing cover CV need only be opened when the trailing edge of the document D passes the reading position RP). That is, an unauthorized user has a high possibility of intentionally causing a document transport error by opening the document transport unit 1 or the opening / closing cover CV. For this reason, if the document transport error is caused by a change from the closed state of the document transport unit 1 or the opening / closing cover CV to the open state, the scan control unit 210 determines that the document transport error is a specific error (intentional by the user). It is determined that the error may occur.

  When the scan control unit 210 determines that the document transport error is a specific error, the scan control unit 210 notifies the main control unit 110 that the document transport error is a specific error. Upon receiving this notification, the main control unit 110 changes the setting of the job mode so that the copy job to be started next is executed in the second mode. That is, when the scan control unit 210 determines that the document transport error that occurred during the execution of the copy job in the first mode is a specific error, the scan control unit 210 detects the occurrence of the document transport error. Then, the copy job started after that is executed in the second mode.

  The control flow when a document transport error occurs during execution of a copy job in the first mode will be described below with reference to the flowchart shown in FIG. The start of the flowchart of FIG. 5 is when the scan control unit 210 detects the occurrence of a document transport error when executing a copy job in the first mode.

  In step S <b> 1, the scan control unit 210 stops the document conveyance operation of the document conveyance unit 1. In step S <b> 2, the scan control unit 210 determines whether or not the document conveyance error is a specific error that is predetermined as being intentionally generated by the user. That is, the scan control unit 210 determines whether or not the document transport error is caused by a change from the closed state to the open state of the document transport unit 1 or the opening / closing cover CV. As a result, if the document transport error is a specific error, the process proceeds to step S3. If the document transport error is not a specific error, the process proceeds to step S4.

  When the process proceeds to step S3, the scan control unit 210 notifies the main control unit 110 that the document transport error is a specific error. Upon receiving this notification, the main control unit 110 changes the setting of the job mode so that the copy job to be started next is executed in the second mode.

  On the other hand, when the process proceeds to step S4, the scan control unit 210 notifies the main control unit 110 that the document conveyance error is not a specific error. Upon receiving this notification, the main control unit 110 maintains the job mode setting so that the next copy job to be started is also executed in the first mode.

(Return to job mode)
If the job mode of the copy job is set to the second mode, it is possible to prevent evasion of accounting. However, if the job mode of the copy job is maintained in the second mode, it takes a long time from the start to the end of the copy job, which impairs the convenience of the user who does not intend to avoid charging. Therefore, the main control unit 110 changes the job mode of the copy job from the first mode to the second mode, and when a predetermined return condition is satisfied, the copy job that starts thereafter starts from the first mode. Change the job mode settings so that

  For example, if the copy job is performed even if the job mode of the copy job is changed from the first mode to the second mode, the user who caused the specific error was not an unauthorized user, or the unauthorized use It is considered that the user has caused a specific error, but the unauthorized user has already left the image forming apparatus 100. In other words, if the number of printed sheets at the time of executing the copy job in the second mode has reached several to several tens, the charge can be avoided even if the job mode of the copy job is returned to the first mode. The nature is low.

  Therefore, after changing the job mode of the copy job from the first mode to the second mode, the main control unit 110 detects the number of printed sheets when the copy job is executed in the second mode. In this configuration, the main control unit 110 corresponds to a “print number detection unit” of the present invention. For example, the main control unit 110 detects the passage of the rear end of the paper P at the detection position DP10 (see FIG. 1), and stores the number of detections in the storage unit 114 as the number of prints. Then, the main control unit 110 determines whether or not to return the job mode of the copy job to the first mode based on the number of printed sheets when the copy job is executed in the second mode. Below, it demonstrates along the flowchart shown in FIG. The flowchart of FIG. 6 starts when a document transport error (specific error) occurs, that is, when the job mode of the copy job is changed from the first mode to the second mode.

  In step S11, the main control unit 110 counts the number of printed sheets when the copy job is executed in the second mode. In step S12, the main control unit 110 determines whether or not the number of printed sheets at the time of executing the copy job in the second mode has reached a predetermined number (several to several tens). To do. As a result, if the number of printed sheets has reached the predetermined number, the process proceeds to step S13, and the main control unit 110 returns the job mode of the copy job to the first mode, assuming that the return condition is satisfied. On the other hand, if the number of printed sheets has not reached the predetermined number, the process returns to step S11. That is, the printing unit 3 executes the copy job in the second mode until the number of printed sheets detected by the main control unit 110 when executing the copy job in the second mode reaches the predetermined number. A copy job that starts later is executed in the first mode.

  Even if the user who caused the specific error is an unauthorized user, if the setting of the job mode of the copy job is changed from the first mode to the second mode, it is not possible to avoid charging, so that the unauthorized user It is considered that the image forming apparatus 100 will not be used for a long time. That is, if a certain amount of time elapses after the job mode of the copy job is changed from the first mode to the second mode, there is a possibility that charging will be avoided even if the job mode of the copy job is returned to the first mode. Is low.

  Therefore, when the scan control unit 210 determines that the document transport error that occurred during the execution of the copy job in the first mode is a specific error, the main control unit 110 starts from the time when the document transport error (specific error) is detected. The elapsed time is counted by the timing unit 113. The main control unit 110 then determines whether or not to return the job mode of the copy job to the first mode based on the elapsed time from the detection of the occurrence of the document conveyance error (specific error). Below, it demonstrates along the flowchart shown in FIG. The flowchart of FIG. 7 starts when a document transport error (specific error) occurs, that is, when the job mode of the copy job is changed from the first mode to the second mode.

  In step S <b> 21, the main control unit 110 causes the time measuring unit 113 to count the elapsed time from the detection of the occurrence of the document conveyance error (specific error). In step S22, the main control unit 110 determines whether or not an elapsed time from the detection of the occurrence of the document conveyance error (specific error) has reached a predetermined time (several tens of hours to 1 hour). To do. As a result, if the elapsed time has reached the predetermined time, the process proceeds to step S23, and the main control unit 110 returns the job mode of the copy job to the first mode, assuming that the return condition is satisfied. On the other hand, if the elapsed time has not reached the predetermined time, the process returns to step S21. That is, the printing unit 3 executes the copy job in the second mode until the elapsed time from the time when the occurrence of the document conveyance error (specific error) detected by the timing unit 113 reaches the predetermined time, and at the predetermined time. From the copy job that starts after reaching, it is executed in the first mode.

  The image forming apparatus 100 is equipped with, for example, a user authentication function (login function). In the image forming apparatus 100 equipped with a user authentication function, authentication information for performing user authentication is registered in advance and stored in the storage unit 114. Then, the user who receives authentication first operates the operation panel 8 and inputs his / her authentication information (for example, a user name and password).

  When the user inputs authentication information, main controller 110 compares the authentication information entered by the user with previously registered authentication information, and determines whether the user who entered the authentication information can be authenticated. To do. If the main control unit 110 determines that the user who has input the authentication information can authenticate, the main control unit 110 gives permission to use the image forming apparatus 100 to the user who has input the authentication information. In this configuration, the main control unit 110 corresponds to the “authentication unit” of the present invention.

  Here, even if the user who logged in to the image forming apparatus 100 is an unauthorized user, another user logs in to the image forming apparatus 100 after the user (unauthorized user) logs out of the image forming apparatus 100. For example, it is clear that the current user is different from the previous user (illegal user). Therefore, when the user authentication function is installed in the image forming apparatus 100, it may be determined whether or not to return the job mode of the copy job to the first mode according to the flowchart shown in FIG. In the flowchart of FIG. 8, after a document transport error (specific error) occurs and the job mode of the copy job is changed from the first mode to the second mode, the authenticated user is notified of the image forming apparatus 100. Start when permission is granted.

  In step S <b> 31, the main control unit 110 determines whether the user who has given permission to use the image forming apparatus 100 (the user who has logged in to the image forming apparatus 100) has changed. As a result, if the user has changed, the process proceeds to step S32, and if the user has not changed, the process proceeds to step S33. In step S32, the main control unit 110 returns the job mode of the copy job to the first mode on the assumption that the return condition is satisfied. On the other hand, when the process proceeds to step S33, the main control unit 110 maintains the job mode of the copy job in the second mode. That is, the printing unit 3 executes a copy job in the first mode when a user who is permitted to use the image forming apparatus 100 is replaced. As a result, even if the job mode of the copy job is changed from the first mode to the second mode because the previous user is an unauthorized user, the job mode of the copy job is changed to the first mode when the next user uses it. Since the mode is returned to the 1 mode, the next user can finish the copy job promptly.

  When the process proceeds from step S31 to step S33 and the job mode of the copy job is maintained in the second mode, the number of printed sheets when the copy job is executed in the second mode has reached a predetermined number of printed sheets. The job mode of the copy job may be returned to the first mode (the control shown in FIG. 6 may be performed). Alternatively, the job mode of the copy job may be returned to the first mode after the elapsed time from the time when the occurrence of the document conveyance error is detected reaches a predetermined time (the control shown in FIG. 7 is performed). Also good).

  By the way, an unauthorized user may repeatedly avoid charging. Therefore, when an unauthorized user who wants to avoid charging uses the image forming apparatus 100, the frequency of occurrence of a specific error that occurs during execution of a copy job increases.

  Therefore, the main control unit 110 stores usage history data including the frequency of occurrence of a specific error that occurred during the execution of the copy job for each user. Then, when the frequency of occurrence of the specific error indicated by the usage history data corresponding to the authenticated user is equal to or higher than the predetermined value, the main control unit 110 prevents the authenticated user from escaping the charge. The job mode is changed to the second mode (the printing unit 3 executes a copy job in the second mode).

  For example, the main control unit 110 stores the occurrence rate of the specific error (for example, the ratio of the occurrence frequency of the specific error with respect to the number of documents conveyed) as a value indicating the occurrence frequency of the specific error. If the occurrence rate of the specific error is equal to or greater than the predetermined occurrence rate, the main control unit 110 determines that the occurrence frequency of the specific error is equal to or greater than the predetermined value, and changes the job mode of the copy job to the second mode. .

  Alternatively, the main control unit 110 stores the number of originals conveyed without occurrence of the specific error after the occurrence of the specific error as a value indicating the frequency of occurrence of the specific error. Then, the main control unit 110 determines that the occurrence frequency of the specific error is equal to or greater than a predetermined value if the number of documents conveyed without a specific error after the occurrence of the specific error is equal to or less than the predetermined number. The job mode of the copy job is changed to the second mode. In this case, the job mode of the copy job may be returned to the first mode if the number of originals conveyed without a specific error after the occurrence of the specific error exceeds a predetermined number.

  As described above, the image forming apparatus 100 according to the present embodiment is a chargeable type capable of executing a copy job that conveys the document D, reads the document D being conveyed, and prints an image of the read document D on the paper P. The image forming apparatus includes a reading table 20 and a document conveying path 10 passing through the reading table 20, and a document conveying unit 1 that conveys the document D along the document conveying path 10 and the reading table 20. An image reading unit 2 for reading the original D, a first mode for printing an image of the original D read by the image reading unit 2 on the paper P in parallel with the reading of the original D by the image reading unit 2, and an image reading unit The copy job in any one of the second modes in which printing of the image of the original D read by the image reading unit 2 on the paper P after the original D read by 2 is discharged from the original conveyance path 10 Printing section 3 that executes A scan that detects whether a document transport error has occurred while the document transport unit 1 is transporting the document D, and stops the transport of the document D by the document transport unit 1 when the document transport error is detected. Each time the control unit 210 and the printing unit 3 perform printing, the copy fee of the document D is charged, and when the scan control unit 210 detects the occurrence of a document transport error, the document D transported when the document transport error is detected. And a charging device 9 that does not charge for the copy fee. Then, when the scan control unit 210 detects the occurrence of a conveyance error during execution of the copy job in the first mode, the scan control unit 210 generates a specific error that is predetermined as a document error that can be intentionally generated by the user. If the scan controller 210 determines that the document transport error is a specific error, the printing unit 3 starts copying after the scan controller 210 detects the occurrence of the document transport error. Run the job in the second mode.

  When the job mode of the copy job is the first mode, the image of the document D read by the image reading unit 2 is printed on the paper P in parallel with the reading of the document D by the image reading unit 2. For this reason, if a document conveyance error occurs at the timing when the reading of the document D by the image reading unit 2 is finished, the copy fee of the document D is not limited even though the image of the document D is normally printed on the paper P. Not charged. Therefore, if the document transport error that occurred during the execution of the copy job in the first mode is a specific error (an error that is predetermined as a result that can be intentionally generated by the user), the document transport error can be avoided. It may have been intentionally generated by an unauthorized user.

  On the other hand, when the job mode of the copy job is the second mode, the image of the document D read by the image reading unit 2 is discharged after the document D read by the image reading unit 2 is discharged from the document transport path 10. Printing on the paper P is started. In the second mode, the time taken from the start to the end of the copy job is longer than in the first mode. However, even if a document transport error is intentionally generated by an unauthorized user who wants to avoid charging, printing of the image of the document D transported at the time of the document transport error on the paper P has not started. Prevent billing evasion.

  Therefore, in the present embodiment, when a document transport error occurs during execution of a copy job in the first mode, the document transport error is a specific error (an error that is predetermined as an error that can be intentionally generated by the user). If so, the copy job that starts thereafter is executed in the second mode. As a result, it is possible to prevent repeated evasion of charges.

  In this embodiment, as described above, after changing the job mode of the copy job from the first mode to the second mode, a predetermined return condition (the job mode of the copy job is returned to the first mode). If the (condition) is satisfied, the job mode of the copy job is returned to the first mode. Thereby, it can suppress that the convenience of the user who is not intending to avoid charge is impaired. For example, when the number of printed sheets at the time of executing a copy job in the second mode reaches a predetermined number, or the elapsed time from the detection of occurrence of a document conveyance error (specific error) is determined in advance. When the predetermined time is reached, the job mode of the copy job is returned to the first mode. Alternatively, in the image forming apparatus 100 equipped with the user authentication function, when the authenticated user is changed, the job mode of the copy job is returned to the first mode.

  It should be thought that embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is shown not by the description of the above-described embodiment but by the scope of claims for patent, and further includes meanings equivalent to the scope of claims for patent and all modifications within the scope.

DESCRIPTION OF SYMBOLS 1 Document conveyance unit 2 Image reading part 3 Printing part 9 Billing device 10 Document conveyance path 20 Reading stand 110 Main control part (print number detection part, authentication part)
113 Timekeeping unit 210 Scan control unit (error occurrence detection unit)
CV open / close cover D Original P Paper

Claims (7)

A charge-type image forming apparatus capable of carrying out a copy job for conveying a document, reading a document being conveyed, and printing an image of the read document on paper,
A reading table;
An original conveying unit having an original conveying path passing through the reading table, and conveying an original along the original conveying path;
An image reading unit for reading a document on the reading table;
A first mode in which a document image read by the image reading unit is printed on a sheet in parallel with reading of the document by the image reading unit, and the document read by the image reading unit is discharged from the document conveyance path A printing unit that executes the copy job in any one mode of a second mode in which printing of a document image read by the image reading unit on the paper later is started;
Detecting whether or not a document transport error has occurred while the document transport unit is transporting a document, and detecting the occurrence of an error that stops the document transport by the document transport unit when the document transport error is detected. And
Each time the printing unit performs printing, the copy fee of the document is charged. And a charging device that does not charge,
The error occurrence detection unit is predetermined to detect that the document conveyance error can be intentionally generated by the user when the occurrence of the document conveyance error is detected when the copy job is executed in the first mode. Determine if it is a specific error,
When the error occurrence detection unit determines that the document conveyance error is the specific error, the printing unit performs the copy job that starts after the error occurrence detection unit detects the occurrence of the document conveyance error. An image forming apparatus that executes in the second mode. The document conveying unit is supported to be openable and closable with respect to the reading table,
The error occurrence detection unit detects opening / closing of the document conveyance unit when the copy job is executed in the first mode, and when the document conveyance unit is opened, the document conveyance error occurs. The image forming apparatus according to claim 1, wherein the image forming apparatus determines that the document transport error is the specific error. The document transport unit includes an opening / closing cover for exposing the document transport path,
The error occurrence detection unit detects opening / closing of the opening / closing cover during execution of the copy job in the first mode, and detects that the document conveyance error has occurred when detecting that the opening / closing cover is opened. The image forming apparatus according to claim 1, wherein the image forming apparatus recognizes and determines that the document transport error is the specific error. A print number detecting unit for detecting the number of printed sheets when the copy job is executed in the second mode;
The printing unit executes the copy job in the second mode until the number of prints detected by the print number detection unit reaches a predetermined number, and the number of prints detected by the print number detection unit is 4. The image forming apparatus according to claim 1, wherein the copy job that starts after reaching the predetermined number is executed in the first mode. 5. When the error occurrence detection unit determines that the document transport error that has occurred during execution of the copy job in the first mode is the specific error, the elapsed time from the time of detection of the occurrence of the document transport error is counted. It has a timer,
The printing unit executes the copy job in the second mode until the elapsed time counted by the timing unit reaches a predetermined time, and the elapsed time counted by the timing unit. 5. The image forming apparatus according to claim 1, wherein the copy job that starts after the predetermined time is reached is executed in the first mode. 6. The authentication information registered in advance for authenticating the user is compared with the authentication information entered by the user, and if the user who entered the authentication information determines that authentication is possible, the authentication information is entered. It has an authentication unit that gives the user permission to use the image forming apparatus,
The printing unit, after the error occurrence detection unit determines that the document transport error that occurred during the execution of the copy job in the first mode is the specific error, and when the authenticated user is replaced, The image forming apparatus according to claim 1, wherein the copy job is executed in a first mode. The authentication unit stores, for each user, usage history data including the frequency of occurrence of the specific error that occurred during the execution of the copy job,
The printing unit executes the copy job in the second mode when the occurrence frequency of the specific error indicated by the use history data corresponding to the authenticated user is equal to or greater than a predetermined value. The image forming apparatus according to claim 6.

Images