JP6708155B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus that ejects ink from a nozzle for printing and performs a punching process on a printed material.

A post-processing device (finisher) may be attached to a printing device such as a printer or a multifunction peripheral. Some post-processing devices can perform punching processing (punching processing) and stapling processing. A part of the image of the printed matter may be scraped (broken) by the post-processing. Patent Document 1 describes an example of a technique relating to partial loss of an image by post-processing.

Specifically, in Patent Document 1, image data for a plurality of pages is input, print data for forming an image on a sheet is generated based on the input image data, and an instruction to process the sheet is accepted. For each page, determine the overlap between the image position of the image formed on the paper that is determined by the print data and the processing position of the paper that is determined by the processing instruction, and the paper on which the image of the page that is determined to overlap is formed. In addition, an image processing apparatus that displays a processing state image of a sheet whose processing position has been processed is described. With this configuration, it is possible to confirm the image that is cut by the processing of the sheet before the image is formed on the sheet (Patent Document 1: Claim 1, paragraph [0004]).

JP, 2007-034444, A

Some printing apparatuses (post-processing apparatuses) perform punching processing. For example, when a printed matter is filed, a setting for performing punching processing is made. The perforation is performed by passing a punching blade through the paper. As a result of the punching process, it is possible to obtain a sheet (printed matter) in which holes have been punched.

Some printing devices use ink. In such a printing apparatus, droplets of water-soluble or oil-based ink are ejected onto the paper. The part where the ink is ejected becomes soft. More ink is sprayed on the higher density portion. The higher the density, the lower the rigidity of the paper. Poor drilling may not be possible due to reduced rigidity.

For example, there is a case where the paper (punching waste) at the punched portion cannot be completely separated from the printed matter. In other words, the punch scraps may not be completely sheared. In this case, it is necessary to manually remove the remaining punch scraps. Further, when the punching blade is passed through the paper, the softened portion of the fiber of the paper around the punching may be dragged by the punch scraps. As a result, the perforations may not be clean circles. As described above, there is a problem that when punching a printed matter of ink, a punching failure may occur.

According to the technique described in Patent Document 1, it is possible to confirm and adjust an image (preview image) to be cut by the processing of the paper before printing. However, control and operation become complicated. Therefore, it takes time and labor until the printing starts. Further, in the technique described in Patent Document 1, it is necessary to store print data for a plurality of sheets. Therefore, a large capacity image memory is required. In particular, some printing apparatuses that use ink can print 100 sheets or more per minute (for example, 150 sheets). Therefore, in the technique described in Patent Document 1, the printing apparatus becomes large in size and high in cost. Therefore, the above problems cannot be solved sufficiently.

In view of the above problems, the present invention prevents perforation defects in printed matter of ink while suppressing the complexity, size, and cost of the device.

In order to solve the above problems, an image forming apparatus according to a first aspect of the present invention includes a sheet conveying unit, a recording unit, a punching unit, and a control unit. The paper transport unit transports paper. Based on the image data, the recording unit ejects ink onto a conveyed sheet to record an image. The punching unit passes through the recording unit and punches the image-recorded sheet before discharge . In the image data, the control unit does not cause the recording unit to eject ink at a pixel that includes a pixel corresponding to a perforation and that is included in a non-ejection region that is a region wider than the perforation.

According to the present invention, it is possible to prevent the perforation failure due to the decrease in rigidity due to ink, while suppressing an increase in size and cost. The image forming apparatus does not become complicated or large.

FIG. 1 is a diagram showing an example of a multifunction peripheral according to an embodiment. FIG. 1 is a diagram showing an example of a multifunction peripheral according to an embodiment. FIG. 3 is a diagram showing an example of an ink ejection control mechanism according to the embodiment. It is a figure which shows an example of the post-processing apparatus which concerns on embodiment. It is a figure which shows an example of the post-processing apparatus which concerns on embodiment. It is a perspective view showing an example of a punching part concerning an embodiment. It is a perspective view showing an example of a punching part concerning an embodiment. It is the figure which expanded the cam which concerns on embodiment. 6 is a flowchart showing an example of non-ejection control during perforation processing in the multifunction machine according to the embodiment. It is a figure which shows an example of the non-ejection area|region setting screen which concerns on embodiment. It is a figure which shows an example of the non-ejection area|region which concerns on embodiment. It is a figure which shows an example of the non-ejection area|region setting data D1 which concerns on embodiment. It is a figure which shows an example of the non-ejection area|region which concerns on a 1st modification. It is a figure which shows an example of the non-ejection area|region which concerns on a 2nd modification.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. Hereinafter, the multifunction peripheral 100 will be described as an example of the image forming apparatus. The multifunction device 100 is of an inkjet type.

(Outline of multifunction device 100)
First, the outline of the multifunction peripheral 100 according to the embodiment will be described with reference to FIGS. 1 and 2. 1 and 2 are diagrams illustrating an example of the multifunction peripheral 100 according to the embodiment.

The multi-function device 100 includes a control unit 1. The control unit 1 controls each unit of the multifunction peripheral 100. The control unit 1 includes a CPU 11 and an image processing unit 12. The CPU 11 performs calculation and processing based on the control program and control data stored in the storage unit 2. The storage unit 2 includes a non-volatile storage device such as a ROM, a HDD, and a flash ROM, and a volatile storage device such as a RAM. The image processing unit 12 performs image processing on image data used for printing.

The multifunction machine 100 includes an operation panel 3. The operation panel 3 includes a display panel 31 and a touch panel 32. The display panel 31 displays a setting screen and information. The display panel 31 displays operation images such as keys, buttons, and tabs. The touch panel 32 detects a touch operation on the display panel 31. Based on the output of the touch panel 32, the control unit 1 recognizes the operated operation image. The control unit 1 recognizes the setting operation performed by the user.

The multi-function peripheral 100 includes a paper feed unit 4, a paper transport unit 5, and a recording unit 6. Plural sheet feeding units 4 are provided. Each sheet feeding unit 4 accommodates a sheet bundle. Each sheet feeding unit 4 includes a sheet feeding roller 41. For a print job, the control unit 1 selects any one of the paper feed units 4. The control unit 1 selects the sheet feeding unit 4 selected by the input to the operation panel 3. Further, the control unit 1 automatically selects the paper feeding unit 4 that accommodates the size of paper used in the print job. In the case of a print job, the control unit 1 rotates the paper feed roller 41 of the selected paper feed unit 4. By rotating the paper feed roller 41, paper is supplied from the selected paper feed unit 4.

The paper transport unit 5 transports paper. In FIG. 2, the paper transport path is indicated by a thick line. A plurality of pairs of transport rollers are provided along the transport path. The paper transport unit 5 includes a transport unit 51. The transport unit 51 includes a drive roller 52 and a plurality of driven rollers 53. The transport unit 51 also includes a transport belt 54 that is wound around a drive roller 52 and each driven roller 53. The paper transport unit 5 includes one or more transport motors 56 that rotate each transport roller pair and the drive roller 52. At the time of printing, the control unit 1 rotates the carry motor 56. As a result, each transport roller pair rotates. Further, the conveyor belt 54 circulates. As a result, the paper supplied from the paper supply unit 4 is conveyed toward the recording unit 6. Further, the recorded (printed) paper is ejected outside the machine. The discharge destination includes the discharge tray 55 and the post-processing device 7.

The discharge tray 55 is attached to the upper portion of the right side surface of the multifunction peripheral 100. The post-processing device 7 is attached to the left side surface of the multifunction peripheral 100. In FIG. 2, a part of the post-processing device 7 is shown by a broken line. The control unit 1 conveys the sheet that has passed through the recording unit 6 toward the discharge tray 55 or the post-processing device 7. When the setting for performing the post-processing is made on the operation panel 3, or when the setting is made such that the post-processing device 7 is the discharge destination, the control unit 1 directs the paper toward the post-processing device 7 and the paper transport unit 5. To transport. When the discharge tray 55 is set as the discharge destination on the operation panel 3, the control unit 1 causes the paper that has passed through the recording unit 6 to be conveyed to the paper conveying unit 5 toward the discharge tray 55.

Further, the paper transport unit 5 includes a suction unit 57. The suction unit 57 sucks the sheet onto the transport belt 54. The position of the sheet and the distance between each nozzle 62 and the sheet are fixed. At the time of printing, the control unit 1 operates the suction unit 57. For example, the suction unit 57 applies a voltage to the driven roller 53. As a result, the transport belt 54 electrostatically attracts the paper. When releasing the electrostatic attraction, the control unit 1 causes the attraction unit 57 to ground the conveyor belt 54.

The recording unit 6 records an image by ejecting ink onto the conveying paper. In other words, the recording unit 6 prints. As shown in FIGS. 1 and 2, the recording unit 6 includes a plurality of line heads 60. The multifunction device 100 includes four line heads 60 (60Bk, 60C, 60M, 60Y). Each line head 60 is fixed. Each line head 60 is provided above the conveyor belt 54. A certain gap is provided between each line head 60 and the conveyor belt 54. The line head 60Bk ejects black ink. The line head 60C ejects cyan ink. The line head 60M ejects magenta ink. The line head 60Y ejects yellow ink.

An ink tank 61 (61Bk, 61C, 61M, 61Y) that supplies ink is provided for each line head 60. The ink tank 61Bk containing the black ink supplies the ink to the line head 60Bk. An ink tank 61C that stores cyan ink supplies ink to the line head 60C. An ink tank 61M containing magenta ink supplies ink to the line head 60M. An ink tank 61Y that stores yellow ink supplies ink to the line head 60Y.

Each line head 60 includes a plurality of nozzles 62 (see FIG. 3). The opening of each nozzle 62 faces the conveyor belt 54. Ink is ejected from each nozzle 62. The ink lands on the transport paper. As a result, an image is recorded (formed). The nozzles 62 are arranged in the main scanning direction (the direction orthogonal to the paper transport direction, the direction perpendicular to the paper surface of FIG. 2). The interval between the nozzles 62 in the main scanning direction is one pixel pitch.

The multi-function device 100 includes a reading unit 9. The reading unit 9 includes a document feeding section 91 and an image reading section 92. The document transport unit 91 transports a document to the reading position. The image reading unit 92 reads the conveyed document. It should be noted that the document feeder 91 can lift and open the front side of the multifunction peripheral 100. It is possible to open and close the document feeding unit 91 and set one document on the image reading unit 92. The image reading unit 92 can also open and close the document feeding unit 91 to read the set document. The image reading unit 92 generates image data of the read document.

The control unit 1 is also connected to the communication unit 13. The communication unit 13 includes communication hardware (connector, circuit) and software. The communication unit 13 communicates with the computer 200. The computer 200 is, for example, a PC or a server. The control unit 1 receives print data from the computer 200. The print data includes print settings and print contents. For example, the print data includes data described in the page description language. The control unit 1 (image processing unit 12) analyzes the received (input) print data. Based on the received print data, the control unit 1 generates image data (raster data) used for image formation in the recording unit 6.

(Ink ejection control)
Next, an example of ink ejection control in the multifunction peripheral 100 according to the embodiment will be described with reference to FIG. FIG. 3 is a diagram showing an example of an ink ejection control mechanism according to the embodiment.

As shown in FIG. 3, each line head 60 includes a plurality of drivers 63. Further, each line head 60 includes a plurality of nozzles 62. The nozzles 62 are formed so that the intervals in the main scanning direction are even. For example, each nozzle 62 is formed by etching or perforating a metal plate.

One drive element 64 (piezoelectric element) is provided for one nozzle 62. The drive element 64 is, for example, a piezo element or PZN. The driver 63 turns ON/OFF the voltage application to each drive element 64. For example, each driver 63 applies a pulsed voltage to the drive element 64 corresponding to the nozzle 62 that should eject ink. The driving element 64 is deformed in shape by applying a voltage. The pressure of the shape change is applied to the flow path (not shown) that supplies the ink to the nozzle 62. Ink is ejected from the nozzle 62 by the pressure on the flow path. Each driver 63 does not apply a voltage to the drive element 64 corresponding to the pixel that does not eject ink. In this way, the driver 63 actually controls the ejection of ink. Note that, in FIG. 3, for convenience, only one line head 60</b>C of the plurality of line heads 60 is illustrated as a part of the inside. The configuration of the line head 60 is the same for each color.

Specifically, the control unit 1 (image processing unit 12) generates image data for transmission to each line head 60. The control unit 1 generates image data instructing ejection or non-ejection of ink for each pixel. The control unit 1 transmits the generated image data to each line head 60. That is, the image data transmitted from the control unit 1 to each driver 63 is data (binary data) for instructing ejection or non-ejection of ink. For example, the control unit 1 (image processing unit 12) transmits the image data to each driver 63 on a line-by-line basis in the main scanning direction.

The control unit 1 also supplies a clock signal to each driver 63. The ink ejection cycle (frequency) is determined based on the clock signal. In the case of a print job, the period in which each driver 63 applies a voltage to each drive element 64 is constant. The paper conveyance speed is a speed at which the paper moves by one dot (one line) in one ejection cycle. The controller 1 causes the paper transport unit 5 (transport unit 51) to transport the paper at a predetermined paper transport speed. Based on the image data, the driver 63 applies a voltage to the drive element 64 of the pixel (nozzle 62) from which ink should be ejected. By repeating this process from the beginning to the end of the page in the paper transport direction (sub-scanning direction), one page is printed.

(Post-processing device 7)
Next, the outline of the post-processing device 7 according to the embodiment will be described with reference to FIGS. 4 to 8. 4 and 5 are diagrams illustrating an example of the post-processing device 7 according to the embodiment. 6 and 7 are perspective views showing an example of the punch unit 8 according to the embodiment. FIG. 8 is an enlarged view of the cam 84 according to the embodiment.

The post-processing device 7 is a device for performing various types of post-processing on printed paper. The post-processing device 7 can be attached to the multifunction peripheral 100. The printed sheet that has passed through the recording unit 6 is discharged from the discharge roller pair 58 (discharge port). The post-processing device 7 includes a carry-in port 7a. The printed paper is sent into the post-processing device 7 from the carry-in port 7a.

As shown in FIG. 4, the post-processing device 7 includes a post-processing control unit 70. As shown in FIG. 5, the post-processing device 7 includes an upper discharge tray 71, a first discharge tray 72, a second discharge tray 73, a punch unit 8, a staple unit 74, and a processing tray unit 75.

The post-processing control unit 70 controls the operation of each unit of the post-processing device 7. The post-processing control unit 70 is a substrate including a memory and a processing circuit such as a CPU and a microcomputer. The control unit 1 gives an instruction to the post-processing control unit 70. The post-processing device 7 controls the operation of the post-processing device 7 based on an instruction from the control unit 1.

In the post-processing device 7, a plurality of sheet-conveying roller pairs 76 are provided. Each roller pair 76 is rotated by the driving force of a motor (not shown). The post-processing control unit 70 rotates each roller pair 76 to convey the paper inside the post-processing device 7.

The upper discharge tray 71 is provided on the upper surface of the post-processing device 7. The first discharge tray 72 is provided above the second discharge tray 73. The discharge destination (the discharge tray to be used) can be set on the operation panel 3. The punching section 8 is a section for punching a sheet. When the punching process is set on the operation panel 3, the post-processing control unit 70 causes the punching unit 8 to perform the punching process on the sheet. When the operation panel 3 is not set to perform punching processing, the post-processing control unit 70 does not allow the punching unit 8 to perform punching processing on a sheet. The processing tray unit 75 is a unit for stacking a stack of sheets in units of copies. The stapling section 74 is a section that performs stapling processing on the sheet bundle stacked on the processing tray section 75.

A first sorting guide 77 and a second sorting guide 78 are provided in order to sort the destinations of the sheets in the post-processing device 7. The first sorting guide 77 is provided near the carry-in port 7a. The second sorting guide 78 is provided between the carry-in port 7 a and the processing tray unit 75. A motor (not shown) is provided for each of the first sorting guide 77 and the second sorting guide 78. Each sorting guide rotates. The post-processing control unit 70 rotates the first sorting guide 77 and the second sorting guide 78 according to the setting of the discharge destination.

When the sheet is set to be discharged to the first discharge tray 72, the post-processing control unit 70 sets the first sorting guide 77 so that the paper is directed to the first discharge tray 72 after passing through the punch unit 8 (arrow A in FIG. 5 ). Then, the second sorting guide 78 is rotated. When the sheet is set to be discharged to the upper discharge tray 71, the post-processing control unit 70 rotates the first sorting guide 77 so that the sheet carried in from the carry-in port 7a is directed upward (direction B in FIG. 5). As a result, the paper is discharged to the upper discharge tray 71. When the staple processing is set, the post-processing control unit 70 rotates the first sorting guide 77 and the second sorting guide 78 so that the sheet is guided in the direction of the processing tray unit 75 (direction C in FIG. 5). Let The post-processing control unit 70 reversely feeds the sheet bundle after the stapling process by the stapling unit 74. As a result, the sheet bundle is discharged to the second discharge tray 73 (direction D in FIG. 5).

Next, an example of the punch unit 8 according to the embodiment will be described with reference to FIGS. 4 and 6 to 8. In FIGS. 6 to 8, arrows indicating directions are attached. The directions indicated by the arrows correspond to the front and rear, the upper and lower sides, and the left and right sides of the punch unit 8 (the multifunction machine 100100, the post-processing device 7).

As shown in FIG. 4, the punch unit 8 includes a punch motor 81, a shaft 82, a motor drive unit 83 (motor driver), a cam 84, and a vertical movement unit 85. The vertical movement unit 85 includes a contact member 86, a punching blade 87, and an elastic member 88. An outline arrow in FIG. 4 is a force transmission path of the punch motor 81.

The punch motor 81 reciprocates the punching blade 87. For example, the punch motor 81 may be a DC brush motor. The motor drive unit 83 turns on/off the supply of current to the punch motor 81. The post-processing control unit 70 controls the motor drive unit 83. The post-processing control unit 70 controls the rotation and stop of the punch motor 81.

As shown in FIGS. 6 and 7, the punch section 8 includes an upper guide section 89 and a lower guide section 810. The upper guide portion 89 and the lower guide portion 810 guide the paper. The sheet enters and passes between the upper guide portion 89 and the lower guide portion 810. A vertical movement unit 85 is provided above the upper guide unit 89. The shaft 82 and the cam 84 are provided above the contact member 86. The punch motor 81 rotates the shaft 82. The cam 84 is attached to the shaft 82.

A plurality of vertical moving parts 85 (a combination of the contact member 86, the punching blade 87, and the elastic member 88) are provided. The punching blade 87 punches a sheet. The contact member 86 is provided above the punching blade 87. The upper end of the punching blade 87 contacts the lower surface of the contact member 86. The piercing blade 87 is, for example, a metal pipe. A blade is provided at the lower tip. The upper guide portion 89 and the lower guide portion 810 have holes (not shown) at positions corresponding to the punching blades 87. The punching blade 87 moves downward, and the lower end of the punching blade 87 hits the sheet. Further, by moving the punching blade 87 downward, a hole is made in the paper. After punching, the post-processing control unit 70 retracts the punching blade 87 so as not to obstruct the next sheet of paper. The scraps generated by punching (punching scraps) drop into a scrap tank (not shown) provided below the lower guide portion 810.

The shaft 82 is provided above each vertical movement portion 85. The shaft 82 is attached to the rotary shaft of the punch motor 81. By rotating the punch motor 81, the shaft 82 rotates. For example, when the punch motor 81 is rotated once, the shaft 82 is rotated once. The shaft 82 is supported by the support shaft member 82a. The cam 84 is attached to the shaft 82 at a position corresponding to the vertical movement portion 85. 6 and 7 show an example in which four cams 84 are attached to the shaft 82. The mounting angle of each cam 84 is the same. FIG. 6 shows a state in which the cam cover 84a is attached. FIG. 7 shows a state in which the cam cover 84a is removed.

An abutting member 86 is provided below the shaft 82 (cam 84). The cam 84 has an elliptical (egg) shape when viewed from the axial direction of the shaft 82. The cam 84 and the upper surface of the contact member 86 are in contact with each other. Depending on the rotation angle of the shaft 82, the wall thickness of the cam 84 at the portion in contact with the contact member 86 changes. That is, the amount by which the cam 84 pushes the contact member 86 downward (in the direction of the punching blade 87) changes according to the rotation angle of the shaft 82. As a result, the punching blade 87 reciprocates according to the rotation of the cam 84. The shaft 82 and the cam 84 use the driving force of the punch motor 81 to move the punching blade 87 up and down.

6 and 7 show an example in which four vertical moving parts 85 are provided (corresponding to the four-hole method). Here, the punch unit 8 includes a shift mechanism 811 that shifts the shaft 82 in the front-rear direction so that 2-hole punching and 4-hole punching can be switched. As shown in FIG. 7, there are two rows (two) of cams 84 corresponding to the inner two vertical moving portions 85. Since there are two cams 84, the inner two cams 84 come into contact with the corresponding abutting members 86 regardless of whether the shaft 82 is shifted forward or backward. That is, in any of the two holes and the four holes, the two inner punching blades 87 punch. As shown in FIG. 7, the cams 84 corresponding to the two outer vertical movement portions 85 are arranged in one row (one). By shifting the shaft 82, it is possible to select contact or non-contact between the two outer cams 84 and the corresponding contact members 86.

When the punching process with two holes is selected on the operation panel 3, the post-processing control unit 70 does not bring the two outer cams 84 into contact with the corresponding contact members 86. In the non-contact state, the cam 84 swings idle. Therefore, the two outer punching blades 87 do not move vertically. FIG. 6 shows an example of the non-contact state. When the punching process with four holes is selected on the operation panel 3, the post-processing control unit 70 brings the two outer cams 84 into contact with the corresponding contact members 86. In the contact state, the two outer punching blades 87 move up and down.

Here, any one of the rotation angle ranges of the shaft 82 where the conveyed sheet and the punching blade 87 are not in contact with each other is set as the reference angle. A sensor (not shown) for recognizing the rotation angle of the shaft 82 is provided. The post-processing control unit 70 recognizes the rotation angle of the shaft 82 based on the output of the sensor. In the post-processing device 7, the rotation angle of the shaft 82 when the punching blade 87 is lifted up is set as the reference angle. During punching of one sheet, the shaft 82 starts rotating from the reference angle. After punching, the post-processing control unit 70 returns the rotation angle of the shaft 82 to the reference angle.

(Non-ejection control during punching process)
Next, an example of non-ejection control at the time of punching processing in the multifunction peripheral 100 according to the embodiment will be described with reference to FIGS. 9 to 12. FIG. 9 is a flowchart showing an example of non-ejection control during punching processing in the multi-function peripheral 100 according to the embodiment. FIG. 10 is a diagram showing an example of the non-ejection area setting screen 3a according to the embodiment. FIG. 11 is a diagram showing an example of the non-ejection region F1 according to the embodiment. FIG. 12 is a diagram showing an example of the non-ejection area setting data D1 according to the embodiment.

In the multifunction device 100, the control unit 1 determines the non-ejection area F1 in the image data during the punching process. The control unit 1 determines the region including the pixel corresponding to the perforation and wider than the perforation as the non-ejection region F1. The control unit 1 does not cause the recording unit 6 to eject ink in the pixels included in the non-ejection area F1. This prevents punching and a reduction in the rigidity of the paper around the punching. Therefore, poor drilling is less likely to occur.

The start in FIG. 9 is the time when the punching process is performed and the print job is started. In the multifunction peripheral 100, print jobs include a copy job, a box print job, and a printer job. At the time of a copy job, a document is set on the reading unit 9. The reading unit 9 reads a document. The control unit 1 causes the recording unit 6 to record an image based on the image data read from the document. At the time of a box print job, the image data stored in the recording unit 6 in a nonvolatile manner is read. The control unit 1 causes the recording unit 6 to record an image based on the read image data. In the case of a printer job, the communication unit 13 receives print data from the computer 200. The control unit 1 generates image data used for a print job based on the print data. The control unit 1 causes the recording unit 6 to record an image based on the generated image data and the settings included in the print data.

First, the control unit 1 recognizes a punching pattern in a print job (step #1). Specifically, the control unit 1 recognizes the number of perforations. The control unit 1 confirms whether to punch two holes or four holes.

In the case of a copy job or a box print job, the user can set the number of punches on the operation panel 3. For a printer job, the user can set the number of perforations on the computer 200. The computer 200 includes information indicating the number of punched holes in the print data. The communication unit 13 receives the print data. The control unit 1 recognizes the number of perforations based on the received print data. In this way, the control unit 1 can recognize the punching pattern based on the setting made on the operation panel 3 or the data received by the communication unit 13.

The control unit 1 determines the number of non-ejection areas F1 included in one page (step #2). The control unit 1 sets the number of non-ejection areas F1 and the number of perforations (perforation pattern) to be the same. In the case of two holes, the control unit 1 sets the number of non-ejection areas F1 to two. In the case of four holes, the control unit 1 sets the number of non-ejection areas F1 to four. In this way, the control unit 1 changes the number of non-ejection areas F1 according to the punching pattern.

Next, the controller 1 determines the size of the non-ejection area F1 (step #3). In addition, the control unit 1 sets the sizes of the non-ejection regions F1 to be the same. In the case of two holes, the control unit 1 makes the sizes of the two non-ejection regions F1 the same. In the case of four holes, the control unit 1 makes the sizes of the four non-ejection areas F1 the same.

Here, on the operation panel 3, a method of determining the size of the non-ejection area F1 can be selected. Selection of the determination method will be described with reference to FIG. FIG. 10 shows an example of the non-ejection area setting screen 3a. When a predetermined operation is performed on the operation panel 3, the control unit 1 displays the non-ejection area setting screen 3a on the display panel 31. Note that the control unit 1 may display the non-ejection area setting screen 3a on the display panel 31 after starting the execution of the print job for performing the punching process and before starting the paper feeding.

A default button B1, a size designation button B2, and a paper thickness button B3 are provided on the non-ejection area setting screen 3a. When setting the size of each non-ejection area F1 as the default value, the user operates the default button B1. The default diameter (width) of each non-ejection region F1 is, for example, 11 mm. The diameter of the punching blade 87 is about 6 to 7 mm. The default value is an example, and may be smaller than 11 mm. The default value may be greater than 11 mm. The operation panel 3 accepts a selection to make the non-ejection area F1 the default size. When the default size is selected, the control unit 1 determines the size of each non-ejection area F1 as the default size.

When the size of each non-ejection area F1 is set to a desired size, the user operates the size designation button B2. Below the size designation button B2, a size input field C1 is provided. When the size input field C1 is operated, the control unit 1 causes the display panel 31 to display a software keyboard capable of inputting numbers. Using the software keyboard, the user inputs the desired diameter (width). The control unit 1 displays the input diameter in the size input field C1. The controller 1 determines the input diameter as the size of each non-ejection area F1. That is, the operation panel 3 receives the setting of the size of the non-ejection area F1. The control unit 1 sets the non-ejection area F1 having the size set on the operation panel 3.

When the size of each non-ejection area F1 is set according to the thickness of the paper, the user operates the paper thickness button B3. Here, the operation panel 3 receives the setting of the size and thickness (type of paper) of the accommodated paper for each paper feed unit 4. For example, the paper type can be set from thick paper, plain paper, and thin paper. For a print job, the control unit 1 selects the paper feeding unit 4 to be used. The control unit 1 recognizes the thickness of the sheet accommodated in the selected sheet feeding unit 4 based on the preset sheet thickness setting. The control unit 1 determines the size of each non-ejection area F1 based on the recognized thickness of the sheet. The control unit 1 reduces the non-ejection area F1 as the sheet is thicker. The thinner the paper, the larger the non-ejection area F1.

Next, the control unit 1 determines the non-ejection area F1 in the image data (step #4). In other words, the control unit 1 determines the range of pixels to be treated as the non-ejection area F1 in the image data. The controller 1 sets the number of non-ejection regions F1 determined based on step #2. The controller 1 determines the non-ejection area F1 having the size determined based on step #3.

First, the control unit 1 makes the non-ejection area F1 circular. Further, the control unit 1 matches the center of the perforation with the center of the non-ejection area F1. The control unit 1 also makes the diameter (width) of the non-ejection region F1 larger than the diameter of the perforations. If the non-ejection area F1 is large, the area of the lost image is large. Therefore, the control unit 1 makes the diameter of the non-ejection region F1 smaller than twice the diameter of the perforation. Therefore, a lower limit and an upper limit may be set for the numerical values that can be input in the size input field C1. For example, when the diameter of the perforations is 7 mm, the lower limit is 8 mm and the upper limit is 14 mm.

Here, an example of setting the non-ejection area F1 will be described with reference to FIG. FIG. 11 shows an example of image data when four holes are provided. FIG. 11 shows an example of image data of a solid image with one color or a plurality of colors. The upper diagram of FIG. 11 shows an example of image data before the non-ejection area F1 is set. The lower part of FIG. 11 shows an example of image data after setting the non-ejection area F1. The control unit 1 transmits the image data in the state shown in the lower side of FIG. 11 to the recording unit 6.

In the lower diagram of FIG. 11, the non-ejection region F1 is shown in an enlarged manner. In the enlarged view, the broken line is the edge of the region corresponding to the perforation. The solid line is the outer circumference of the non-ejection area F1. In this way, the control unit 1 defines the non-ejection area F1 so as to surround the perforation. In the example of FIG. 11, the center of the hole and the center of the non-ejection area F1 coincide.

The interval between the centers of adjacent holes in the main scanning direction is defined by the standard. The intervals between the punching blades 87 are in accordance with the standard so that the punched sheets can be bound in a file. In FIG. 11, the interval of perforations according to the standard is indicated by L1. The standard also defines the distance from the edge of the paper to the center of the perforation in the sub-scanning direction.

Then, in the multi-function device 100 and the post-processing device 7, the sheet is conveyed by the central sheet passing method. The center sheet feeding method is a method in which the center of the sheet in the main scanning direction (direction perpendicular to the conveying direction) and the center of the conveying path in the width direction (main scanning direction) are aligned. In FIG. 11, a line corresponding to the center of the sheet in the main scanning direction is shown by a broken line. The midpoint of the distance between the two central perforations overlaps the center line.

In the image data, the control unit 1 defines the pixels corresponding to the positions of perforations according to the standard and the periphery of these pixels as the non-ejection area F1. For example, the control unit 1 refers to the non-ejection area setting data D1 and sets the non-ejection area F1. The non-ejection area setting data D1 is stored in the storage unit 2.

The non-ejection area setting data D1 defines a range (coordinates) of pixels to be treated as the non-ejection area F1 in the image data for each number of perforations, paper size, and size (diameter, width) of the non-ejection area F1. The data. FIG. 12 shows an example of the non-ejection area setting data D1 (data table). The control unit 1 refers to the portion corresponding to the determined number of perforations (perforation pattern), the determined size of the non-ejection area F1, and the paper size used for printing in the non-ejection area setting data D1. Then, the control unit 1 sets the pixel defined in the reference portion as the pixel of the non-ejection area F1.

The control unit 1 transmits the image data to the recording unit 6 while converting the pixel values of the pixels included in the non-ejection area F1 in the image data (step #5). The control unit 1 prevents the pixels included in the non-ejection area F1 from ejecting ink. In other words, the control unit 1 changes the pixel value of the pixel included in the non-ejection area F1 to the value of ink non-ejection. That is, the control unit 1 performs the masking process only on the pixels included in the non-ejection area F1.

In the image data given to each line head 60, when the value of “1” means ink ejection and the value of “0” means ink non-ejection, the control unit 1 controls the pixel values of all the pixels included in the non-ejection area F1. To "0". For this processing, the control unit 1 (image processing unit 12) includes a mask processing unit 12a. The mask processing unit 12a may be provided as hardware. Further, it may be implemented as software by a program and a circuit in the control unit 1 (image processing unit 12). In the signal supplied to each line head 60 as image data, the mask processing unit 12a fixes the signal value of the pixel included in the non-ejection area F1 to a constant value (value indicating non-ejection).

During the punching process, the control unit 1 transmits the image data to the recording unit 6 (each line head 60) while masking the specific pixels. In the case of a print job including a plurality of pages, the pixel values of the pixels in the non-ejection area F1 are converted on each page. Eventually, the image data of all pages included in the print job are transmitted (step #6). This completes this flow.

In this way, the image forming apparatus according to the embodiment includes the paper transport unit 5, the recording unit 6, the punch unit 8, and the control unit 1. The paper transport unit 5 transports paper. The recording unit 6 records an image by ejecting ink on a conveyed sheet based on the image data. The punching unit 8 punches a sheet on which an image has been recorded. The control unit 1 does not cause the recording unit 6 to eject ink in the pixels included in the non-ejection region F1 that is a region wider than the perforation and that includes the pixel corresponding to the perforation.

As a result, in the image data, the perforations and the area around the perforations can be set as the areas where ink is not ejected. As a result, ink is not ejected to the perforations and the area around the perforations in the paper. It is possible to suppress the reduction in rigidity of the portion to be perforated and the periphery of the perforation. Therefore, it is possible to prevent the perforation failure in the printed matter of the ink. Moreover, it is not necessary to mount a large amount of image memory. Therefore, it is possible to prevent the image forming apparatus from increasing in size and cost. There is no need for complicated operations and controls such as adjusting the image position on the preview image. An image forming apparatus that is easy to use and easy to operate can be provided.

Further, the punch section 8 has a plurality of punch patterns. The control unit 1 changes the number of non-ejection areas F1 according to the punching pattern. Accordingly, it is possible to set an appropriate non-ejection area F1 according to the punching pattern. No defects occur in all perforations.

In addition, the control unit 1 matches the center of the perforation with the center of the non-ejection area F1, and makes the non-ejection area F1 circular. Thereby, the non-ejection area F1 can be set so as to cover the perforations. Further, the perforations can be uniformly surrounded by the non-ejection area F1.

Further, the diameter of the non-ejection region F1 is larger than the diameter of the perforations and smaller than twice the diameter of the perforations. As a result, a region that is neither too small nor too large can be the non-ejection region F1.

It also includes an operation unit that receives the setting of the size of the non-ejection area F1. The control unit 1 sets the non-ejection area F1 having the size set by the operation unit. This allows the user to set the size of the non-ejection area F1. It is possible to set the non-ejection area F1 of a size desired by the user.

The thicker the paper, the harder it is for ink ejected on one side to reach the other side. Therefore, the thicker the paper, the more difficult the rigidity of the paper is to decrease. On the contrary, the thinner the paper, the lower the rigidity tends to be due to the ejected ink. Therefore, the control unit 1 recognizes the thickness of the paper. The control unit 1 makes the non-ejection area F1 smaller as the sheet is thicker. The control unit 1 increases the non-ejection area F1 as the sheet is thinner. Thereby, the non-ejection area F1 having a size corresponding to the thickness of the paper can be set. When the paper is thick, the non-ejection area F1 can be made as small as possible.

Although the embodiment of the present invention has been described above, the scope of the present invention is not limited to this, and various modifications can be made without departing from the scope of the invention.

A modified example will be described with reference to FIGS. 13 and 14. FIG. 13 is a diagram showing an example of the non-ejection area F1 according to the first modification. FIG. 14 is a diagram showing an example of the non-ejection region F1 according to the second modification.

(First modification)
In the above-described embodiment, the example in which the circular non-ejection area F1 is determined has been described. However, the shape of the non-ejection area F1 is not limited to a circle. As shown in FIG. 13, it may be a quadrangle. The non-ejection area F1 may be rectangular or square. Further, it may be a polygon other than a quadrangle.

(Second modified example)
In the above-described embodiment, an example in which one ejection failure region F1 is defined for each hole has been described. However, as shown in FIG. 14, the control unit 1 may set one non-ejection region F1 so as to cover all the perforations. As a result, it is less likely to be affected by the decrease in the rigidity of the paper due to the ink adhesion. It is possible to prevent perforation defects in printed matter of ink. Further, the setting process of the non-ejection area F1 is easy. For example, when printing on a sheet such as thin paper that originally has low rigidity, the control unit 1 may set one ejection failure area F1 so as to cover all the perforations.

INDUSTRIAL APPLICABILITY The present invention can be used for an image forming apparatus that prints using ink and performs perforation processing.

100 MFP (image forming device)
1 Control unit 3 Operation panel (operation unit)
5 Paper Transport Section 6 Recording Section 8 Punch Section F1 Non-ejection Area

Claims (7)

A paper transport unit for transporting paper,
A recording unit that records an image by ejecting ink on a conveyed sheet based on image data,
A punch unit that passes through the recording unit and punches a recorded sheet before ejection ,
Of the image data, a control unit that does not cause the recording unit to eject ink at a pixel included in a non-ejection region that is a region wider than the perforation and that includes a pixel corresponding to the perforation.
An image forming apparatus comprising:
The punch section has a plurality of punching patterns,
The image forming apparatus according to claim 1, wherein the control unit changes the number of the non-ejection regions according to the punching pattern. 3. The image forming apparatus according to claim 1, wherein the control unit matches the center of the perforation with the center of the non-ejection area and makes the non-ejection area circular. The image forming apparatus according to claim 3, wherein a diameter of the non-ejection region is larger than a diameter of the perforation and smaller than twice the diameter of the perforation. Including an operation unit that receives the setting of the size of the non-ejection region,
The image forming apparatus according to claim 1, wherein the control unit sets the non-ejection area having a size set by the operation unit. The control unit is
Recognize the thickness of the paper,
The thicker the paper, the smaller the non-ejection area,
The image forming apparatus according to any one of claims 1 to 5, wherein the thinner the sheet is, the larger the non-ejection area is. The image forming apparatus according to claim 1, wherein the control unit sets one area, which covers all the perforations , of the image data as the non-ejection area.