JP6996223B2 - Image forming device - Google Patents

Description

The present disclosure relates to an image forming apparatus.

In recent years, electrophotographic image forming devices have become widespread. When printing an image on continuous paper by an electrophotographic image forming apparatus, it is preferable to keep the image spacing on the continuous paper constant in order to efficiently perform various processes. Therefore, a process of forming a mark on the continuous paper and forming an image on the continuous paper in response to the detection of the mark is performed (see, for example, Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 2004-268405 Japanese Unexamined Patent Publication No. 2014-052433

However, in the prior art as described in Patent Documents 1 and 2, in a situation where printing is interrupted in the middle and then continuous paper is rewound to resume printing, the printed image area is detected to be offset before the interruption. If it is detected by the part, the image area may be erroneously detected as the edge of the continuous paper.

The present disclosure has been made in view of such a situation, and makes it possible to avoid erroneous detection of the edge of the continuous paper even if there is a printed image on the continuous paper.

The image forming apparatus, which is one aspect of the present disclosure, includes a conveying unit that conveys continuous paper according to a conveying path, an image forming portion that forms an image on the continuous paper, and a traveling direction of the continuous paper conveyed by the conveying unit. The offset detection unit that detects the edge of the continuous paper in the direction orthogonal to the image and the continuous paper that is arranged upstream of the offset detection unit in the traveling direction of the continuous paper and is conveyed by the transport unit. A mark detection unit that detects marks formed corresponding to each of the formed images, and a control unit that controls the transport unit, the image forming unit , the offset detection unit , and the mark detection unit . The control unit is in a state where the continuous paper is rewound by the transport unit after the image formation by the image forming unit is interrupted and the image formation by the image forming unit is resumed. When the rear end of the final image of the images formed on the continuous paper passes through the offset detection unit, the image has a function of setting the detection function of the offset detection unit to the ON state and the mark detection unit. In a state where the rear end of the final image is specified according to the detection result and the image formation by the image forming unit is resumed, the continuous paper is placed between the sensors between the offset detection unit and the mark detection unit. A second distance obtained by adding the distance and the first distance obtained by multiplying the detection cycle for detecting the edge of the continuous paper by the offset detection unit, the number of detections, and the transport line speed of the continuous paper is carried. After that, it has a function of determining the writing timing so that the first image is written by the image forming unit .

Further, when the continuous paper is further provided with a fixing unit for heating and pressurizing, the control unit releases the interruption of image formation by the image forming unit, and the temperature adjustment of the fixing unit is completed. It is preferable that the continuous paper is rewound by the transport unit.

Further, it is preferable that the control unit sets the detection function to the off state until the rear end of the final image passes through the offset detection unit.

Further, the control unit is based on at least one of the reverse transport time for rewinding the continuous paper, the reverse transport distance for rewinding the continuous paper, and the number of images formed on the continuous paper. , It is preferable to specify the final image.

Further, the waiting time required for the continuous paper to be conveyed from the mark detection unit to the offset detection unit is set, and the control unit detects the rear end of the final image by the mark detection unit. When the waiting time has elapsed, it is preferable to set the detection function to the ON state.

Further, it is preferable that the control unit causes the image forming unit to form the mark corresponding to the final image when the image forming unit gives an instruction to interrupt the image formation.

Further, the image forming apparatus, which is one aspect of the present disclosure, includes a conveying unit that conveys continuous paper according to a conveying route, an image forming portion that forms an image on the continuous paper, and the continuous paper conveyed by the conveying unit. The control unit includes a bias detection unit that detects the edge of the continuous paper in a direction orthogonal to the traveling direction, a control unit that controls the transport unit, the image forming unit, and the offset detection unit. Is an image formed on the continuous paper in a state where the continuous paper is rewound by the transport unit after the image formation by the image forming unit is interrupted and the image formation by the image forming unit is resumed. Of these, when the rear end of the final image passes through the offset detection unit, it has a function to set the detection function of the offset detection unit to the ON state, and the image formation by the image forming unit is restarted. The print position of the image formed by the image forming unit is not corrected while the image forming unit is writing the first image before the correction according to the detection result of the offset detection unit. It has a function of forming an identification mark indicating the effect corresponding to the image formed by the image forming unit .

Further, the control unit switches whether or not to make the image forming unit write the first image after making corrections according to the detection result of the offset detection unit. When writing is performed after correction according to the detection result of the offset detection unit, among the transport state of the continuous paper, the type of the continuous paper, and the printing accuracy of the image formed by the image forming unit. It is preferable to determine the writing timing of the first image by the image forming unit according to at least one.

Further, when the correction amount to the print position of the final image is between the upper limit value and the lower limit value and exceeds the preset upper limit correction threshold value, the control unit has the detection result of the offset detection unit. If the amount of correction to the print position of the final image is between the upper limit value and the lower limit value and does not exceed the upper limit correction threshold value, the offset is offset. It is preferable that the writing is performed before the correction according to the detection result of the detection unit.

Further, when the control unit causes the image forming unit to write the first image before making correction according to the detection result of the offset detection unit, the image forming unit corrects the printing position of the first image. Until the amount is fixed, it is preferable to correct the print position of the image formed by the image forming unit with the correction amount of the printing position of the final image before the interruption of the image formation by the image forming unit.

Further, when the control unit causes the image forming unit to write the first image before making corrections according to the detection result of the offset detection unit, the first image and the final image by the image forming unit are used. It is preferable to adjust the spacing between the images, including the final image, to the spacing between previously formed images.

Further, it is preferable that the control unit forms the identification mark around the image in which the print position is not corrected among the images formed by the image forming unit.

According to one aspect of the present disclosure, even if there is a printed image on the continuous paper, it is possible to avoid erroneous detection of the edge portion of the continuous paper.

It is a figure which shows the whole structure example of the image forming apparatus 1 which concerns on embodiment of this disclosure. It is a figure which shows the functional structure example of the image forming apparatus 1 which concerns on embodiment of this disclosure. It is a figure explaining an example in which the mark M is printed for each image I in the operation outline of the post-interruption resumption printing which concerns on embodiment of this disclosure. It is a figure which shows the operation example which determines the final image I_last by the count of the number of marks M which concerns on embodiment of this disclosure. It is a figure which shows the operation example which determines the final image I_last by printing only the mark M only in the final image I_last which concerns on embodiment of this disclosure. It is a figure which shows the operation example which determines the final image I_last by the first image I which detected the mark M after the re-carrying distance at the start of resumption printing after interruption which concerns on embodiment of this disclosure elapses a preset distance. .. It is a figure which concretely explains an example in which the mark M_10 is printed only in the final image I_last in the operation outline of the post-interruption resumption printing which concerns on embodiment of this disclosure. It is a figure which shows an example in which the writing timing of the 1st image is determined after the correction amount which concerns on embodiment of this disclosure is determined. It is a figure which shows an example in which the writing timing of the 1st image is determined with emphasis on the accuracy which concerns on embodiment of this disclosure. It is a figure which shows an example in which the writing timing of the 1st image is determined with emphasis on the reduction of spoilage which concerns on embodiment of this disclosure. It is a figure which shows an example which the final image I_last is specified after the printing is restarted which concerns on embodiment of this disclosure. It is a figure which shows an example which the print position of the image I shifts after resuming the offset detection which concerns on embodiment of this disclosure, and before the correction amount is fixed. It is a figure which shows an example which prints the identification mark N corresponding to the image I which was printed in the non-guaranteed period until the correction amount is fixed after the offset detection is restarted which concerns on embodiment of this disclosure. It is a flowchart explaining the operation example at the time of resuming printing after interruption which concerns on embodiment of this disclosure. It is a flowchart explaining an example of the normal image-drawing mode determination process which concerns on embodiment of this disclosure. It is a flowchart explaining an example of the early drawing mode determination process which concerns on embodiment of this disclosure.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the present disclosure is not limited to the following embodiments.

FIG. 1 is a diagram showing an overall configuration example of the image forming apparatus 1 according to the embodiment of the present disclosure. FIG. 2 is a diagram showing a functional configuration example of the image forming apparatus 1 according to the embodiment of the present disclosure. FIG. 3 is a diagram illustrating an example in which a mark M is printed for each image I in the operation outline of post-interruption restart printing according to the embodiment of the present disclosure. The image forming apparatus 1 includes an image forming apparatus main body 7, and a paper feed adjusting unit 4 is connected to the front stage side of the image forming apparatus main body 7, and a paper feeding unit 3 is connected to the front stage side of the paper feed adjusting unit 4. ing. A mark detection unit 5 is provided between the image forming apparatus main body 7 and the paper feed adjusting unit 4. The mark detection unit 5 detects the mark M on the continuous paper P conveyed by the transfer unit 21. The mark M is formed corresponding to each of the images I formed on the continuous paper P. A take-up adjustment unit 8 is connected to the paper ejection side of the image forming apparatus main body 7, and a take-up unit 9 is connected to the paper ejection side of the take-up adjustment unit 8. The paper feed unit 3 has a function of storing and holding the continuous paper P and feeding the continuous paper P to the image forming apparatus main body 7. The continuous paper P is, for example, roll paper. The winding unit 9 has a function of holding the continuous paper P discharged from the image forming apparatus main body 7. The paper feed adjusting unit 4 has a buffer function for absorbing a minute speed difference and deviation between the paper feed unit 3 and the image forming apparatus main body 7. The take-up adjustment unit 8 has a buffer function for absorbing a minute speed difference and deviation between the take-up unit 9 and the image forming apparatus main body 7. Further, the image forming apparatus 1 is provided with a transport unit 21. The transport unit 21 includes various rollers such as a transport roller 31 and a resist roller 32, and transports the continuous paper P along the transport path 22. The transport path 22 feeds and transports the continuous paper P. In the transport path 22, the continuous paper P accommodated in the paper feed unit 3 is fed, and the continuous paper P is conveyed to the image forming unit 23 via the transport roller 31 and the resist roller 32. Further, a offset detection unit 11 is provided on the transport unit 21. The offset detecting unit 11 detects the end portion of the continuous paper P in the direction orthogonal to the traveling direction of the continuous paper P conveyed by the conveying unit 21.

The image forming apparatus 1 includes an image forming unit 23 for forming an image I on a continuous paper P in the image forming apparatus main body 7, and a setting unit 6 is provided on the upper part of the image forming apparatus main body 7. The setting unit 6 includes a display unit 61 and an operation unit 62, and receives an operation of an operator via the operation unit 62 and displays information by the display unit 61. For example, various settings for printing operations are set. It can be performed. Further, an automatic document feeding device and a document image scanning device for automatically reading a document are provided on the image forming apparatus main body 7. The document image scanning device can read the document through the platen glass. The document image scanning device reads the document, for example, and stores the image information of the scanned document in an image memory (not shown) or the like. The image information of the manuscript is used for image formation by the image forming unit 23. The image forming unit 23 is provided on the rear side of the mark detecting unit 5, and includes a photoconductor 44 prepared for each color such as cyan, magenta, yellow, and black, and around each photoconductor 44. A charging device 41, an exposure device 42, and a developing device 43 are provided.

The surface of the photoconductor 44 charged by the charging device 41 is exposed to an image by the exposure device 42 based on the image information of the original image stored in the image memory or the like, and an electrostatic latent image is formed. The electrostatic latent image is developed by the developing device 43 to become a toner image. The toner image is transferred to the intermediate transfer belt 46. The toner image transferred to the intermediate transfer belt 46 is transferred to the continuous paper P transported along the transport path 22 by the transport unit 21 while being crimped by the secondary transfer roller 47. The toner image that has been pressure-bonded and transferred by the secondary transfer roller 47 is heated and pressed by the fixing portion 25 to be fixed on the continuous paper P. That is, the image forming unit 23 transfers the toner image to the continuous paper P by forming an image by an electrophotographic process. A drum cleaning device 45 is provided around the photoconductor 44. The drum cleaning device 45 removes the residual toner remaining on the intermediate transfer belt 46.

The control unit 101 includes a CPU, a ROM, a RAM, a storage unit (not shown), and the like. The CPU reads a program from the ROM according to the processing content, expands it into the RAM, and controls the operation of the image forming apparatus 1 in cooperation with the expanded program. The storage unit is realized by a non-volatile semiconductor memory such as a flash memory or a hard disk drive, and various data are stored. Various data stored in the storage unit are referred to when the CPU controls the operation of the image forming apparatus 1. The control unit 101 controls the transport unit 21, the image forming unit 23, the fixing unit 25, the mark detection unit 5, the offset detection unit 11, the setting unit 6, and the like. The control unit 101 joins the continuous paper P in a state where the continuous paper P is rewound by the transport unit 21 after the formation of the image I by the image forming unit 23 is interrupted and the formation of the image I by the image forming unit 23 is resumed. When the rear end of the final image I_last of the formed images I passes through the offset detection unit 11, the detection function of the offset detection unit 11 is set to the ON state. The control unit 101 identifies the rear end of the final image I_last according to the detection result of the mark detection unit 5.

Specifically, as shown in FIG. 3, in the resume printing after interruption, the mark M corresponding to the already printed final image I_last is detected by the mark detection unit 5. Based on the detection result of the mark detection unit 5, for example, timing control is performed to write the image I from the start position of the first image in which printing is restarted, and the image I is written. Writing the image I is an operation in which the exposure apparatus 42 exposes the surface of the photoconductor 44 to form an electrostatic latent image on the surface of the photoconductor 44. Therefore, the timing control for writing the image I is equivalent to controlling the timing at which the exposure apparatus 42 exposes the surface of the photoconductor 44. In one example of FIG. 3, the images I_1 to the image I_9 were being printed sequentially, but since the printing was interrupted when the image I_10 was printed, the final image I_last is the image I_10 and corresponds to the image I_10. The mark M is the mark M_10. In this case, the image I_10, which is the final image I_last, is pulled back to the upstream side from the formation start position in preparation for restarting printing, and printing is restarted. The formation start position of the image I such as the image I_10 is the start position on the continuous paper P of the image I formed on the continuous paper P. Specifically, the control unit 101 releases the interruption of the formation of the image I by the image forming unit 23, and when the temperature adjustment of the fixing unit 25 is completed, the continuous paper P is pulled back and rewound by the conveying unit 21. .. Further, the waiting time t'required for the continuous paper P to be conveyed from the mark detection unit 5 to the offset detection unit 11 is set. The control unit 101 sets the detection function of the offset detection unit 11 to the off state until the rear end of the final image I_last passes through the offset detection unit 11. When the waiting time t'has elapsed since the rear end of the final image I_last is detected by the mark detection unit 5, the control unit 101 sets the detection function of the offset detection unit 11 to the ON state. In one example of FIG. 3, the control unit 101 specifies the final image I_last based on the reverse transport time T in which the continuous paper P is rewound.

An example of determining the final image I_last will be described with reference to FIGS. 4 to 6. FIG. 4 is a diagram showing an operation example of determining the final image I_last by counting the number of marks M according to the embodiment of the present disclosure. In one example of FIG. 4, the number of marks M during the pulling back of the continuous paper P is counted, and the number of marks M during the restart operation is counted. When the number of marks M being pulled back and the number of marks M being restarted match, it is determined that the image I corresponding to the mark M at that time is the final image I_last, and the image is scheduled to be formed after printing is restarted. The first image is formed in the region R_11. FIG. 5 is a diagram showing an operation example of determining the final image I_last by printing the mark M only on the final image I_last according to the embodiment of the present disclosure. In one example of FIG. 5, the mark M is printed only when the final image I_last is printed, and when the mark M is detected at the time of reprinting, it is determined that the image I corresponding to the mark M at that time is the final image I_last. Then, after resuming printing, the first image is formed in the image formation scheduled area R_11. FIG. 6 shows an operation example in which the final image I_last is determined by the first image I in which the mark M is detected after the re-conveyed distance at the start of restart printing after interruption according to the embodiment of the present disclosure has elapsed a preset distance. It is a figure which shows. The preset distance is as shown in the following equation (1).

Preset distance = reverse transport distance L_r- {distance between mark detection unit 5 and image stop position + (image length x 1.5 + blank amount) x shrinkage magnification} (1)

The image length is the length along the transport direction of the continuous paper P. The amount of blank space is, for example, 1 mm. Reference numeral 1.5 is a coefficient for ensuring that the immediately preceding mark M passes through the mark detection unit 5, but is not particularly limited thereto.

That is, the control unit 101 has at least one of the reverse transport time T for rewinding the continuous paper P, the reverse transport distance L_r for rewinding the continuous paper P, and the number of images I formed on the continuous paper P. Based on the above, the final image I_last is specified.

FIG. 7 is a diagram specifically illustrating an example in which the mark M_10 is printed only on the final image I_last in the operation outline of the post-interruption restart printing according to the embodiment of the present disclosure. As shown in FIG. 7, the mark M_10 and the image I_10 are printed at the same time only when the final image I_last is formed. When printing is interrupted and preparations are made for resumption, the continuous paper P is rewound by the reverse transport distance L_r. After the standby time t'has elapsed after printing is resumed, the detection function of the offset detection unit 11 is set to the ON state. That is, in a state where the control unit 101 does not form the mark M on the continuous paper P other than the mark M corresponding to the final image I_last, when the image forming unit 23 receives an instruction to suspend the formation of the image I, the final image I_last The mark M corresponding to the above is formed in the image forming unit 23.

Next, the control unit 101 determines the writing timing of the first image by the image forming unit 23 according to the detection result of the offset detection unit 11 in a state where the formation of the image I by the image forming unit 23 is restarted. 8 to 13 will be specifically described with reference to FIGS. 8 to 13. FIG. 8 is a diagram showing an example in which the writing timing of the first image is determined after the correction amount according to the embodiment of the present disclosure is determined. The control unit 101 uses the image forming unit 23 after the time required to determine the correction amount of the print position of the image I formed by the image forming unit 23 after the offset detection unit 11 detects the edge of the continuous paper P. The writing timing of the first image is determined. Therefore, the distance S between the sensors between the mark detection unit 5 and the offset detection unit 11 is the minimum margin region, that is, the spoilage region.

FIG. 9 is a diagram showing an example in which the writing timing of the first image is determined with an emphasis on the accuracy according to the embodiment of the present disclosure. In one example of FIG. 9, the offset detection unit 11 detects the edge of the continuous paper P five times, and then the correction amount is determined. The correction amount may be determined according to the difference between the actual position of the edge of the continuous paper P by the offset detection unit 11 and the position of the edge of the continuous paper P in the specifications. In one example of FIG. 9, for example, the correction amount may be determined according to the final detection result among the five detection results. Further, for example, the correction amount may be determined according to the average value of the five detection results. FIG. 10 is a diagram showing an example in which the writing timing of the first image is determined with an emphasis on reducing spoilage according to the embodiment of the present disclosure. In one example of FIG. 10, the offset detection unit 11 detects the end portion of the continuous paper P once, and then the correction amount is determined. The correction amount may be determined according to the difference between the actual position of the edge of the continuous paper P by the offset detection unit 11 and the position of the edge of the continuous paper P in the specifications.

That is, as shown in FIGS. 9 and 10, the period during which the continuous paper P continues to be conveyed before the correction amount is determined is the variable spoilage region, that is, the spoilage region adjustable period. Further, the spoilage region generation distance L is the total distance between the spoilage region generation distance and the fluctuating spoilage region generation distance along the transport direction of the continuous paper P. As described above, the spoilage region is determined by the distance S between the sensors between the mark detection unit 5 and the offset detection unit 11. The fluctuating spoilage region is determined by the detection cycle × the number of detections × the carrier line speed. Therefore, the control unit 101 determines the writing timing of the first image by the image forming unit 23 according to the number of times the edge of the continuous paper P is detected by the offset detecting unit 11.

Next, a case where the edges of the continuous paper P are offset will be specifically described with reference to FIGS. 11 to 13. FIG. 11 is a diagram showing an example in which the final image I_last is specified after resuming printing according to the embodiment of the present disclosure. In one example of FIG. 11, after the waiting time t'has elapsed from the detection timing of the mark M_10 corresponding to the final image I_last, the mark detection unit 5 starts writing the first image at the time of resuming printing. However, in reality, when the edges of the continuous paper P are offset, it is necessary to obtain the correction amount. FIG. 12 is a diagram showing an example in which the print position of the image I shifts after the offset detection is restarted and before the correction amount is determined according to the embodiment of the present disclosure. As shown in FIG. 12, before the correction amount is confirmed, the print positions of the images I_11 to the image I_13 and the corresponding marks M_11 to the mark M_13 are offset, and after the correction is confirmed after the correction amount confirmation timing, the image I_14. And the offset of the printing position of the corresponding mark M_14 is improved. FIG. 13 is a diagram showing an example of printing the identification mark N corresponding to the image I printed in the non-guaranteed period before the correction amount is fixed after the offset detection is restarted according to the embodiment of the present disclosure. In FIG. 13, it is important to make the image I intervals the same. Before the correction amount is confirmed, the print positions of the images I_11 to I_13 are offset, and after the correction is confirmed after the correction amount confirmation timing, the print positions of the images I_14 to the image I_17 and the corresponding marks M_14 to M_17 are displayed. The offset is improved. In one example of FIG. 13, since the identification mark N is further printed, the identification marks N_11 to N_13 are formed around the images I_11 to 1_13 that have been reprinted before the correction amount is fixed. The identification mark N indicates that the print position of the image I formed by the image forming unit 23 has not been corrected.

That is, when it is important to make the image I intervals the same, the control unit 101 corrects according to the detection result of the offset detection unit 11 in a state where the image I formation by the image forming unit 23 is restarted. Before this, the image forming unit 23 is made to write the first image. Specifically, the control unit 101 switches whether or not to make the image forming unit 23 write the first image after making corrections according to the detection result of the offset detection unit 11. When writing is performed after correction according to the detection result of the offset detection unit 11, the transport state of the continuous paper P, the type of the continuous paper P, and the image I formed by the image forming unit 23. The writing timing of the first image by the image forming unit 23 is determined according to at least one of the printing accuracys. More specifically, when the correction amount of the final image I_last to the print position is between the upper limit value and the lower limit value and exceeds the upper limit correction threshold value, the control unit 101 has a detection result of the offset detection unit 11. Make corrections according to the above and then write. On the other hand, when the correction amount of the final image I_last to the print position is between the upper limit value and the lower limit value and does not exceed the upper limit correction threshold value, the control unit 101 responds to the detection result of the offset detection unit 11. Have the user write before the correction.

When the control unit 101 causes the image forming unit 23 to write the first image before the correction according to the detection result of the offset detection unit 11, the correction amount of the printing position of the first image by the image forming unit 23 is increased. Until it is confirmed, the print position of the image I formed by the image forming unit 23 is corrected by the correction amount to the printing position of the final image I_last before the formation of the image I is interrupted by the image forming unit 23. When the control unit 101 causes the image forming unit 23 to write the first image before the correction according to the detection result of the offset detection unit 11, the interval between the first image and the final image I_last by the image forming unit 23 Is adjusted to the spacing between previously formed images I, including the final image I_last. The control unit 101 corresponds to the image I formed by the image forming unit 23 while the image forming unit 23 is writing the first image before the correction according to the detection result of the offset detecting unit 11. The identification mark N is formed by the image forming unit 23. That is, the control unit 101 forms the identification mark N around the image I whose print position is not corrected in the image I formed by the image forming unit 23.

FIG. 14 is a flowchart illustrating an operation example when printing is resumed after interruption according to the embodiment of the present disclosure. The processes of steps S19 to S25 correspond to the image output mode determination process after restarting. In step S11, the control unit 101 determines whether or not to interrupt printing. When the control unit 101 determines that printing is interrupted (step S11; Y), the control unit 101 shifts to the process of step S12. When the control unit 101 determines that printing is not interrupted (step S11; N), the control unit 101 continues the process of step S11. In step S12, the control unit 101 sets the detection function of the offset detection unit 11 to the off state. In step S13, the control unit 101 reversely conveys the continuous paper P. In step S14, the control unit 101 reverse-transports the image to a position where the final image I_last can be specified, and then stops the reverse transfer. In step S15, the control unit 101 restarts the transfer of the continuous paper P. In step S16, the control unit 101 identifies the final image I_last. In step S17, the control unit 101 determines whether or not the final image I_last has passed the offset detection unit 11. When the control unit 101 determines that the final image I_last has passed the offset detection unit 11 (step S17; Y), the control unit 101 shifts to the process of step S18. When the control unit 101 determines that the final image I_last does not pass through the offset detection unit 11 (step S17; N), the control unit 101 continues the process of step S17. In step S18, the control unit 101 sets the detection function of the offset detection unit 11 to the ON state.

In step S19, the control unit 101 determines whether or not the correction amount for the final image I_last exceeds the upper limit correction threshold value. When the control unit 101 determines that the correction amount for the final image I_last exceeds the upper limit correction threshold value (step S19; Y), the control unit 101 shifts to the process of step S20, and executes the normal image output mode determination process in step S20. And end the process. The details of the normal image output mode determination process will be described later. When the control unit 101 determines that the correction amount for the final image I_last does not exceed the upper limit correction threshold value (step S19; N), the control unit 101 shifts to the process of step S21. In step S21, the control unit 101 determines whether or not the continuous paper P is a paper type in which deviation is likely to occur. When the control unit 101 determines that the continuous paper P is a paper type in which deviation is likely to occur (step S21; Y), the control unit 101 shifts to the process of step S22, and in step S22, the normal image output mode determination process is performed. Execute and end the process. When the control unit 101 determines that the continuous paper P is not a paper type in which bias is likely to occur (step S21; N), the control unit 101 shifts to the process of step S23. In step S23, the control unit 101 determines whether or not high-precision offset correction is required. When the control unit 101 determines that high-precision offset correction is required (step S23; Y), the control unit 101 shifts to the process of step S24, and in step S24, executes the normal image output mode determination process. End the process. When the control unit 101 determines that high-precision offset correction is not required (step S23; N), the control unit 101 proceeds to the process of step S25, executes an early image output mode determination process, and ends the process. .. The details of the early image output mode determination process will be described later.

FIG. 15 is a flowchart illustrating an example of the normal image extraction mode determination process according to the embodiment of the present disclosure. In step S41, the control unit 101 determines whether or not the latest correction amount has been determined. When the control unit 101 determines that the latest correction amount has been determined (step S41; Y), the control unit 101 shifts to the process of step S43. When the control unit 101 determines that the latest correction amount has not been determined (step S41; N), the control unit 101 shifts to the process of step S42. In step S42, the control unit 101 returns to the process of step S41 without printing the image I only by transporting the continuous paper P. In step S43, the control unit 101 corrects the print position of the image I with the latest fixed correction amount and prints the image I, and ends the normal image output mode determination process.

FIG. 16 is a flowchart illustrating an example of the early image output mode determination process according to the embodiment of the present disclosure. In step S51, the control unit 101 corrects the print position of the image I by the correction amount to the final image I_last and prints the image I. In step S52, the control unit 101 determines whether or not the latest correction amount has been determined. When the control unit 101 determines that the latest correction amount has been determined (step S52; Y), the control unit 101 shifts to the process of step S53. When the control unit 101 determines that the latest correction amount has not been determined (step S52; N), the control unit 101 returns to the process of step S51. In step S53, the control unit 101 corrects the print position of the image I with the latest fixed correction amount and causes the image I to print, and ends the early image output mode determination process.

By the way, in order to efficiently perform various processing operations such as foil stamping or die cutting on the continuous paper P in printing or processing, it is preferable to keep the interval of the images I on the continuous paper P constant. Further, it is common practice to arrange a mark M on the continuous paper P and adjust the writing timing of the image I on the continuous paper P according to the detection timing of the mark M. Such writing is performed. The timing adjustment is mainly for timing adjustment when performing additional printing on continuous paper P which has been printed or processed in advance, and timing adjustment when restarting the printing operation interrupted for some reason. It is used.

Further, conventionally, the offset detection unit 11 detects the end portion of the continuous paper P in the direction orthogonal to the traveling direction of the continuous paper P, and the position of the detected end portion and the position of the end portion assumed in the specifications are set. The print position of the image I is corrected according to the difference. However, in the image forming apparatus 1, when the continuous paper P is rewound after the printing operation is interrupted and the printing is restarted, if the offset detection unit 11 detects the printed image area before the interruption, the image area is May be erroneously detected as the end of the continuous paper P.

Therefore, in the present embodiment, the continuous paper P is rewound by the transport unit 21 after the formation of the image I by the image forming unit 23 is interrupted, and the formation of the image I by the image forming unit 23 is restarted. When the rear end of the final image I_last of the images I formed on the paper P passes through the offset detection unit 11, the detection function of the offset detection unit 11 is set to the ON state. The image I is not formed on the continuous paper P that passes through the offset detection unit 11 after the detection function of the offset detection unit 11 is set to the ON state. Therefore, even if the continuous paper P has the printed image I, it is possible to avoid erroneous detection of the end portion of the continuous paper P.

Further, according to the present embodiment, since the mark M corresponding to the final image I_last is printed on the continuous paper P, the rear end of the final image I_last is specified according to the detection result of the mark detection unit 5. Thereby, the print position of the final image I_last can be accurately specified.

Further, according to the present embodiment, when the interruption of the formation of the image I by the image forming unit 23 is released and the temperature adjustment of the fixing unit 25 is completed, the continuous paper P is rewound by the conveying unit 21. Therefore, since the image I can be formed on the continuous paper P, the image I can be formed on the continuous paper P as soon as printing is resumed.

Further, according to the present embodiment, the detection function is set to the off state until the rear end of the final image I_last passes through the offset detection unit 11. Therefore, the offset detection unit 11 does not erroneously detect the final image I_last as the end portion of the continuous paper P. Therefore, the reliability of the detection result of the offset detection unit 11 can be improved.

Further, according to the present embodiment, among the reverse transport time T in which the continuous paper P is rewound, the reverse transport distance L_r in which the continuous paper P is rewound, and the number of images I formed on the continuous paper P. The final image I_last is specified based on at least one. Therefore, the final image I_last can be reliably specified. Therefore, since the timing at which the final image I_last passes through the offset detection unit 11 can be specified, the timing at which the detection function of the offset detection unit 11 is controlled from the off state to the on state can be accurately determined.

Further, according to the present embodiment, the standby time t'is set to the time required for the continuous paper P to be conveyed from the mark detection unit 5 to the offset detection unit 11. When the waiting time t'has elapsed since the rear end of the final image I_last is detected by the mark detection unit 5, the detection function of the offset detection unit 11 is set to the ON state. Therefore, it is possible to accurately set the timing for controlling the detection function of the offset detection unit 11 to the on state according to the time when the final image I_last passes from the mark detection unit 5 to the offset detection unit 11.

Further, according to the present embodiment, when the image forming unit 23 receives an instruction to suspend the formation of the image I, the mark M corresponding to the final image I_last is formed by the image forming unit 23. Therefore, when the mark detection unit 5 detects the mark M on the continuous paper P, it is equivalent to the final image I_last passing through the mark detection unit 5. Therefore, since the final image I_last can be specified by detecting a single mark M, the final image I_last can be specified at low cost.

Further, according to the present embodiment, in a state where the formation of the image I by the image forming unit 23 is restarted, the writing timing of the first image by the image forming unit 23 is determined according to the detection result of the offset detection unit 11. To. Since the correction amount of the print position of the image I can be obtained from the detection result of the offset detection unit 11, the writing timing of the first image can be determined after the correction amount of the print position of the image I is obtained.

Further, according to the present embodiment, after the edge of the continuous paper P is detected by the offset detection unit 11, the image is formed after the time required to determine the correction amount of the print position of the image I formed by the image forming unit 23. The writing timing of the first image by the forming unit 23 is determined. Therefore, in order to determine the correction amount of the print position of the image I after grasping the position of the end portion of the continuous paper P, the correction amount of the print position of the image I can be accurately obtained.

Further, according to the present embodiment, the writing timing of the first image by the image forming unit 23 is determined according to the number of times the edge of the continuous paper P is detected by the offset detecting unit 11. Therefore, when the accuracy is emphasized, the number of detections of the end portion of the continuous paper P can be increased, and when the reduction of spoilage is emphasized, the number of detections of the end portion of the continuous paper P can be reduced. Therefore, it is possible to determine the writing timing of the first image by the image forming unit 23 according to what is emphasized.

Further, according to the present embodiment, in a state where the formation of the image I by the image forming unit 23 is resumed, the first image is written to the image forming unit 23 before the correction is made according to the detection result of the offset detection unit 11. Can be done. Therefore, the image forming process can be performed even when it is necessary to form the image I at an early stage.

Further, according to the present embodiment, when the image forming unit 23 is made to write the first image, it is switched whether or not to make the correction according to the detection result of the offset detection unit 11 and then write. Therefore, when writing is performed after correction according to the detection result of the offset detection unit 11, the transport state of the continuous paper P, the type of the continuous paper P, and the printing of the image I formed by the image forming unit 23. The writing timing of the first image by the image forming unit 23 is determined according to at least one of the accuracy. Therefore, the writing timing control of the first image can be performed more finely.

Further, according to the present embodiment, when the correction amount to the print position of the final image I_last is between the upper limit value and the lower limit value and exceeds the upper limit correction threshold value, it depends on the detection result of the offset detection unit 11. Correct and then write. On the other hand, if the amount of correction to the print position of the final image I_last is between the upper limit value and the lower limit value and does not exceed the upper limit correction threshold value, writing is performed before correction according to the detection result of the offset detection unit 11. To do. Therefore, if the print position of the first image is significantly deviated, the detection result of the offset detection unit 11 is used, and if the print position of the first image is not significantly deviated, the offset detection unit 11 is used. It is possible to control not to use the detection result. Therefore, since the control is performed to correct the deviation of the print position only when necessary, the productivity as a whole can be improved.

Further, according to the present embodiment, when the image forming unit 23 is made to write the first image before the correction according to the detection result of the offset detection unit 11, the printing position of the first image by the image forming unit 23 is performed. Until the correction amount of is determined, the print position of the image I formed by the image forming unit 23 is corrected by the correction amount of the printing position of the final image I_last before the interruption of the formation of the image I by the image forming unit 23. Therefore, since the print position of the image I is corrected by the latest correction amount, it is possible to avoid the correction of the print position by the irrelevant correction amount.

Further, according to the present embodiment, when the image forming unit 23 is made to write the first image before the correction according to the detection result of the offset detection unit 11, the first image and the final image by the image forming unit 23 are written. The spacing from I_last is adjusted to the spacing between previously formed images I, including the final image I_last. Therefore, when the intervals between the images I formed before the interruption are the same, the intervals between the images I formed on the continuous paper P after the interruption is resumed can be the same, so that unnecessary blanks are left. It can be avoided.

Further, according to the present embodiment, the image formed by the image forming unit 23 while the image forming unit 23 is writing the first image before the correction is performed according to the detection result of the offset detecting unit 11. An identification mark N indicating that the print position of I has not been corrected is formed in correspondence with the image I formed by the image forming unit 23. Therefore, it is possible to intuitively grasp the section where the print position is not corrected on the continuous paper P.

Further, according to the present embodiment, the identification mark N is formed around the image I in which the print position is not corrected in the image I formed by the image forming unit 23. Therefore, among the images I formed on the continuous paper P, the image I whose print position is not corrected can be intuitively grasped.

Although the image forming apparatus 1 according to the present disclosure has been described above based on the embodiment, the present disclosure is not limited to this, and changes may be made without departing from the gist of the present disclosure.

For example, in the present embodiment, an example in which the continuous paper P is a roll paper has been described, but the present invention is not particularly limited thereto. For example, the continuous paper P may be a form or a long paper. That is, the continuous paper P may be continuous over a certain range. For example, the continuous paper P may be fed from an alternately folded form.

Further, in the present embodiment, an example in which the image forming apparatus 1 includes a paper feeding unit 3, a paper feeding adjusting unit 4, an image forming apparatus main body 7, a winding adjusting unit 8, and a winding unit 9 has been described. It is not particularly limited to this. For example, the image forming apparatus 1 may be composed of only the image forming apparatus main body 7. Further, although the description is omitted in this embodiment, a post-treatment device for performing post-treatment such as laminating or cutting may be connected. The post-processing device may be included inside the image forming apparatus main body 7, the post-processing apparatus may be connected to the image forming apparatus main body 7 to form the image forming apparatus 1, and the post-processing apparatus may be configured in the image forming apparatus 1. It may be connected to form an image forming system.

1 Image forming device, 3 Feeding unit, 4 Feeding adjustment unit, 5 Mark detection unit, 6 Setting unit, 61 Display unit, 62 Operation unit, 7 Image forming device main unit, 8 Winding adjustment unit, 9 Winding unit, 11 pieces Close detection unit 21 Transport unit, 22 Transport path, 23 Image forming section, 25 Fixing section 31 Transport roller, 32 Resist roller 41 Charging device, 42 Exposure device, 43 Developing device, 44 Photoreceptor 45 Drum cleaning device, 46 Intermediate transfer belt , 47 Secondary transfer roller 101 Control unit M, M_1 to M_1 mark, N, N-11 to N-13 Identification mark I, I_1 to I_117 image, I_last final image R_111 Image formation planned area, P continuous paper, L spoiled area Occurrence distance T reverse transport time, t'standby time, S sensor distance, L_r reverse transport distance

Claims (12)

A transport unit that transports continuous paper according to the transport route,
An image forming unit that forms an image on the continuous paper,
A offset detection unit that detects the edge of the continuous paper in a direction orthogonal to the traveling direction of the continuous paper conveyed by the transport unit.
A mark that is arranged upstream of the offset detection unit in the traveling direction of the continuous paper and detects marks formed corresponding to each of the images formed on the continuous paper conveyed by the transport unit. With the detector
A control unit that controls the transport unit, the image forming unit , the offset detection unit , and the mark detection unit .
Equipped with
The control unit
Of the images formed on the continuous paper in a state where the continuous paper is rewound by the transport section after the image formation by the image forming section is interrupted and the image formation by the image forming section is resumed. When the rear end of the final image passes through the offset detection unit, it has a function to set the detection function of the offset detection unit to the ON state and also has a function.
In a state where the rear end of the final image is specified according to the detection result of the mark detection unit and the image formation by the image forming unit is resumed, the continuous paper is used with the offset detection unit and the mark detection unit. The distance between the sensors and the first distance obtained by multiplying the detection cycle for detecting the edge of the continuous paper by the offset detection unit, the number of detections, and the transport line speed of the continuous paper are added. It has a function of determining the writing timing so that the first image is written by the image forming unit after being conveyed by the second distance.
Image forming device. A fixing part that heats and pressurizes the continuous paper,
Further prepare
The control unit
When the interruption of image formation by the image forming portion is released and the temperature adjustment of the fixing portion is completed, the continuous paper is rewound by the conveying portion.
The image forming apparatus according to claim 1 . The control unit
The detection function is set to the off state until the rear end of the final image passes through the offset detection unit.
The image forming apparatus according to claim 1 or 2 . The control unit
The final image is specified based on at least one of the reverse transport time for rewinding the continuous paper, the reverse transport distance for rewinding the continuous paper, and the number of images formed on the continuous paper. ,
The image forming apparatus according to any one of claims 1 to 3 . The waiting time required for the continuous paper to be conveyed from the mark detection unit to the offset detection unit is set.
The control unit
When the waiting time has elapsed since the rear end of the final image was detected by the mark detection unit, the detection function is set to the on state.
The image forming apparatus according to any one of claims 1 to 4 . The control unit
When an instruction to interrupt the formation of an image is received by the image forming portion, the mark corresponding to the final image is formed on the image forming portion.
The image forming apparatus according to any one of claims 1 to 5 . A transport unit that transports continuous paper according to the transport route,
An image forming unit that forms an image on the continuous paper,
A offset detection unit that detects the edge of the continuous paper in a direction orthogonal to the traveling direction of the continuous paper conveyed by the transport unit.
A control unit that controls the transport unit, the image forming unit, and the offset detection unit,
Equipped with
The control unit
Of the images formed on the continuous paper in a state where the continuous paper is rewound by the transport section after the image formation by the image forming section is interrupted and the image formation by the image forming section is resumed. When the rear end of the final image passes through the offset detection unit, it has a function to set the detection function of the offset detection unit to the ON state and also has a function.
In a state where the image formation by the image forming unit is resumed, the image forming unit is being made to write the first image before the correction is performed according to the detection result of the offset detection unit. It has a function of forming an identification mark indicating that the print position of the image formed by the image is not corrected in correspondence with the image formed by the image forming unit .
Image forming device. The control unit
The identification mark is formed around the image in which the print position is not corrected in the image formed by the image forming unit.
The image forming apparatus according to claim 7 . The control unit
When the image forming unit is made to write the first image, it is switched whether or not to make correction according to the detection result of the offset detection unit and then write is performed, and the offset detection unit is used. When writing is performed after correction according to the detection result, depending on at least one of the transport state of the continuous paper, the type of the continuous paper, and the printing accuracy of the image formed by the image forming unit. The writing timing of the first image by the image forming unit is determined.
The image forming apparatus according to any one of claims 1 to 8 . The control unit
If the amount of correction to the print position of the final image is between the upper limit value and the lower limit value and exceeds the preset upper limit correction threshold value, the correction is made according to the detection result of the offset detection unit. Let me write
If the amount of correction to the print position of the final image is between the upper limit value and the lower limit value and does not exceed the upper limit correction threshold value, before the correction is made according to the detection result of the offset detection unit. Let me write
The image forming apparatus according to claim 9 . The control unit
When writing the first image to the image forming unit before making correction according to the detection result of the offset detection unit, until the correction amount of the printing position of the first image by the image forming unit is determined. The printing position of the image formed by the image forming unit is corrected by the correction amount of the printing position of the final image before the interruption of the image formation by the image forming unit.
The image forming apparatus according to any one of claims 8 to 10 . The control unit
When writing the first image to the image forming unit before making correction according to the detection result of the offset detection unit, the distance between the first image and the final image by the image forming unit is set to the final image. Adjust to the spacing between previously formed images, including
The image forming apparatus according to any one of claims 8 to 11 .

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