JP2005212142A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printer which enables a printed image using a plate to be accurately aligned with a platelessly printed image. <P>SOLUTION: This printer comprises a means for printing using the plate, a plateless printing means, an imaging means 60, and a control means 200. The control means 200 is equipped with an area setting means 201 for setting a relative area of the image using the plateless printing means, with respect to the image using the means for the printing using the plate, a position storage means 202 for storing a relative position, a carrying timing detecting means 203 for detecting the timing of the carrying of printed matter, a position computing means 204 for computing a position by processing the image acquired by the imaging means 60, and a printing timing determining means 205 for continuously determining the timing of the printing using the plateless printing means, during printing operations. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a printing apparatus having plate printing means for printing a first image using a printing plate and plateless printing means for printing a second image without using a printing plate.

  A printing apparatus having a plate printing unit that prints a first image using a printing plate and a plateless printing unit that prints a second image without using a printing plate is particularly desirable. It is used for the purpose of so-called variable printing, in which various images are printed with respect to a fixed image). Here, variable printing refers to printing performed by changing the number and address of a fixed image, or printing performed by adding specific information for each retail store to a common flyer or pamphlet, etc. Say. As such a printing apparatus, an apparatus described in Patent Document 1 is known.

In a printing apparatus described in Patent Document 1, an offset printing machine with a plate and an ink jet printing machine without a plate are serially arranged on the same conveyance path, and an ink jet is formed on a fixed image on which offset printing has been performed. A variable image by printing can be added. Since the printing apparatus described in Patent Document 1 employs such a configuration, the registration of a printed image by offset printing and a printed image by ink jet printing is achieved by accurately controlling the conveyance speed. It is supposed to be possible.
JP2002-361833

  However, as described in Patent Document 1, only by accurately adjusting the conveyance speed, in an actual printing operation, a slight paper feed misalignment (for example, a misalignment at the time of delivery due to paper holding, a printing pressure, and the like) This causes a problem that the positioning between the printed image with the plate and the printed image without the plate becomes rough.

  The present invention has been made to solve the above-described problem, and an object of the present invention is to provide a printing apparatus that can accurately match a printed image with a plate and a printed image without a plate.

  According to the first aspect of the present invention, there is provided a plate printing means for printing a first image using a printing plate, and a second image is printed without using the printing plate after printing the first image. And a plateless printing unit that performs a region setting unit that sets a relative region of the second image with respect to the first image, and a region set by the region setting unit. Position storing means for storing a relative position for printing the second image with respect to the first image, and conveying means for conveying printing paper between the plate printing means and the plateless printing means. A conveyance timing detection unit that detects a conveyance timing of the printing paper by the conveyance unit; and a first image on the printing paper that is positioned downstream in the conveyance direction of the plate printing unit and printed by the plate printing unit. Taking pictures continuously during printing And a position calculating means for performing image processing on the first image obtained by the imaging means and calculating a relative position for printing the second image with respect to the first image, and the position calculating means And a printing timing determining means for continuously determining a printing timing by the plateless printing means during a printing operation based on the position calculated by the above and the conveying timing of the printing paper by the conveying means.

  According to a second aspect of the present invention, in the printing apparatus according to the first aspect, the plateless printing unit prints different images sequentially on a printing paper.

  According to a third aspect of the present invention, in the printing apparatus according to the first or second aspect, the plate printing unit prints an image on a printing plate on a plate cylinder based on image data for plate making prepared in advance. A plate making unit is provided, and the region setting unit performs region setting based on the plate making image data or image data related to the plate making image data before printing.

  According to a fourth aspect of the present invention, in the printing apparatus according to any one of the first to third aspects, the imaging region captured by the imaging unit or the imaging region based on the relative position stored in the position storage unit At least one of the image processing areas to be image processed is determined by the position calculation means.

  According to a fifth aspect of the present invention, in the printing apparatus according to any one of the first to fourth aspects, the color control of the printed matter in the plate printing unit is performed based on the image data captured by the imaging unit. Do.

  According to a sixth aspect of the present invention, there is provided a plate printing mechanism for transferring an ink image formed on a printing plate to print a first common image on a printing paper, and a stage subsequent to the plate printing mechanism. A printing apparatus including a plateless printing mechanism capable of sequentially printing different second images for each predetermined number of printed sheets, and picks up an image on printing paper at a subsequent stage of the plate printing mechanism An image pickup unit, obtains a color value or color density of an image on the printing paper based on image data picked up by the image pickup unit, adjusts an ink amount based on the color value or color density, and The printing position of the second image on the printing paper is calculated based on the image data picked up by the means.

  According to the first to third aspects and the seventh aspect of the present invention, the imaging unit that continuously captures the first image on the printing paper printed by the plate printing unit during the printing operation, and the imaging A position calculation unit that performs image processing on the first image obtained by the unit and calculates a relative position for printing the second image with respect to the first image, and a position calculated by the position calculation unit and a conveyance unit. Since the printing timing determining means for continuously determining the printing timing by the plateless printing means during the printing work based on the conveyance timing of the printing paper is provided, the position of the printing image by the plate and the printing image by the plateless printing Can be accurately aligned with the position of.

  According to the fourth aspect of the present invention, at least one of the imaging region imaged by the imaging unit or the image processing region imaged by the position calculation unit is determined based on the relative position stored in the position storage unit. Therefore, the memory capacity and processing capability required for image processing can be reduced.

  According to the fifth aspect of the present invention, since the color tone control of the printed matter in the plate printing unit is performed based on the image data captured by the imaging unit, the imaging unit used for image alignment is used. Color tone control can be executed, and proper printing can be performed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic view of a printing apparatus according to the present invention.

  The printing apparatus according to the present invention is supplied from the plate printing means for printing the first image with the printing plate, the plateless printing means for printing the second image without using the printing plate, and the paper supply unit 31. The sprocket 22 has a paper feed cylinder 17 for delivering the printed material to the plate printing means, and a chain 23 for receiving the printed material printed by the plate printing means from the plate printing means and discharging it to the paper discharge unit 32. The paper discharge cylinder 19 is wound around, an image pickup means 60 for picking up an image printed on the printed material, and a control means 200 described later.

  Here, in this specification, the plate printing means refers to a printing means that performs printing by bringing an image formed with ink formed on a printing plate into contact with a printed material and transferring it, such as offset printing. The plateless printing means refers to printing means that forms an image directly from image data and performs printing, such as ink jet printing.

  The plate printing means records the image on the printing plate on which the images held in the first and second plate cylinders 11 and 12 are not recorded, and then makes the ink supplied to the printing plate into the first The four color printing is performed by transferring to the printed matter held by the first and second impression cylinders 15 and 16 via the second blanket cylinders 13 and 14. The plate printing means includes a first plate cylinder 11, a second plate cylinder 12, a first blanket cylinder 13 provided so as to be in contact with the first plate cylinder 11, and a second plate cylinder. 12, a second blanket cylinder 14 provided so as to be able to contact the first blanket cylinder 12, a first pressure cylinder 15 provided so as to be able to contact the first blanket cylinder 13, and a second blanket cylinder 14. A second impression cylinder 16 provided so as to be in contact with the first impression cylinder 15 and a transfer cylinder 18 for transferring the printed matter received from the first impression cylinder 15 to the second impression cylinder 16 are provided.

  The first impression cylinder 15 and the second impression cylinder 16 provided so as to be in contact with the first blanket cylinder 13 and the second blanket cylinder 14 are respectively connected to the first and second plate cylinders 11, 12 and The diameter of the first and second blanket cylinders 13 and 14 is ½ of the diameter. The first and second impression cylinders 15 and 16 have grippers (not shown) for holding and transporting the leading ends of the printed matter. A sheet feeding cylinder 17 disposed adjacent to the impression cylinder 15 has the same diameter as the first and second impression cylinders 15 and 16. The paper feed cylinder 17 holds and conveys the leading end portion of the printed material supplied one by one from the paper feed unit 31 with a gripper (not shown). The front end portion of the printed matter held by the gripper is held by the gripper of the first impression cylinder 15 when the printed matter is transferred from the paper feed cylinder 16 to the first impression cylinder 15.

  A transfer cylinder 18 disposed between the first impression cylinder 15 and the second impression cylinder 16 includes first and second plate cylinders 11 and 12 and first and second blanket cylinders 13 and 14. It has the same diameter as the diameter. The transfer cylinder 18 conveys the leading end of the printed matter received from the first impression cylinder 15 while holding the leading end of the printed matter by a gripper (not shown), and delivers the leading end of the printed matter to the gripper of the second impression cylinder 16.

  A transfer cylinder 18 disposed between the first impression cylinder 15 and the second impression cylinder 16 includes first and second plate cylinders 11 and 12 and first and second blanket cylinders 13 and 14. It has the same diameter as the diameter. The transfer cylinder 18 conveys the leading end of the printed matter received from the first impression cylinder 15 while holding the leading end of the printed matter by a gripper (not shown), and delivers the leading end of the printed matter to the gripper of the second impression cylinder 16.

  A paper discharge cylinder 19 disposed adjacent to the second impression cylinder 16 has the same diameter as that of the first and second plate cylinders 11 and 12 and the first and second blanket cylinders 13 and 14. Have. The paper discharge cylinder 19 has a structure in which a pair of chains 23 are wound around both ends thereof, and a gripper 30 (see FIG. 4) is disposed on a connecting member (not shown) that connects the pair of chains 23. ing. The leading end portion of the printed matter held by the gripper of the second impression cylinder 16 is held by any gripper 30 of the discharge cylinder 19 when the printed matter is transferred from the second impression cylinder 16 to the discharge cylinder 19. . Then, as the chain 23 moves, the printed material passes through a position facing the imaging unit 60 and the plateless printing unit and is discharged onto the paper discharge unit 32.

  A gear attached to an end portion of the feed cylinder 17 is connected to a gear 26 disposed concentrically with the driven pulley 25. A belt 29 is wound between a driving pulley 28 and a driven pulley 25 that are rotated by driving the motor 27. For this reason, the paper feed cylinder 17 is rotated by the drive of the drive motor 27. On the other hand, the first and second plate cylinders 11 and 12, the first and second blanket cylinders 13 and 14, the first and second impression cylinders 15 and 16, the paper feed cylinder 17, the transfer cylinder 18 and the paper discharge cylinder 19 are connected by the gear attached to the edge part, respectively. For this reason, by driving the drive motor 27, the feed cylinder 17, the first and second impression cylinders 15, 16, the discharge cylinder 19, the first and second blanket cylinders 13, 14, the first, first, The two plate cylinders 11 and 12 and the transfer cylinder 18 rotate in synchronization with each other.

  Around the first plate cylinder 11, an ink supply device 20a for supplying, for example, black (K) ink to the printing plate, and an ink supply device for supplying, for example, magenta (M) ink to the printing plate 20b and dampening water supply devices 21a and 21b for supplying dampening water to the printing plate are arranged. Further, around the second plate cylinder 12, an ink supply device 20c for supplying, for example, cyan (C) ink to the printing plate and an ink for supplying, for example, yellow (Y) ink to the printing plate A supply device 20d and dampening water supply devices 21c and 21d for supplying dampening water to the printing plate are arranged.

  Further, around the first plate cylinder 11 or the second plate cylinder 12, a plate feeding section 33 for supplying a printing plate to the outer peripheral portion of the first plate cylinder 11, and a second plate cylinder, respectively. A plate supply unit 34 for supplying a printing plate to the outer periphery of the first plate cylinder, an image recording device 35 for recording an image on the printing plate mounted on the outer periphery of the first plate cylinder 11, and a second plate cylinder An image recording device 36 for recording an image on a printing plate mounted on the outer peripheral portion of 12 is disposed.

  2 is a schematic side view of the ink supply device 20a, the ink supply device 20b, the ink supply device 20c, and the ink supply device 20d described above (collectively referred to as “ink supply device 20”). Is a plan view thereof. In addition, in FIG. 3, illustration of the ink 50 is abbreviate | omitted.

  The ink supply device 20 has an ink source roller 51 arranged with its axial direction oriented in the width direction of the printed matter (direction orthogonal to the printing direction by the printing press), and a plurality of ink rollers 52 (one in FIG. 2). And an ink transfer roller 53 that swings between an ink base roller 51 and an ink roller 52 disposed at the tip. In addition, the ink supply device 20 is arranged in a row corresponding to the L regions divided in the width direction of the printed matter, and each of the ink supply devices 20 is configured to be able to adjust the opening degree with respect to the outer peripheral surface of the ink source roller 51. 54 (1), 54 (2)... 54 (L) (collectively referred to as “ink key 54”), and is composed of the ink source roller 51 and the ink key 54. The ink 50 can be stored in the ink fountain.

  On the back side of each ink key 54, L eccentric cams for respectively pressing the ink key 54 toward the surface of the ink source roller 51 in order to change the opening degree of each ink key 54 with respect to the ink source roller 51. 55 is disposed. Each of these eccentric cams 55 is connected to an L number of pulse motors 57 for rotating the eccentric cam 55 via a shaft 56.

  When an ink key drive pulse is applied to the pulse motor 57, the eccentric cam 55 is rotated around the shaft 5 by driving the pulse motor 57, and the pressing force to each ink key 54 is changed. The opening degree of the ink key 54 relative to the ink base roller 51 is changed, and the amount of ink supplied to the printing plate is changed.

  FIG. 4 is a schematic side view showing the plateless printing means and the image pickup means 60 together with the paper discharge mechanism such as the paper discharge cylinder 19.

  The pair of chains 23 are stretched endlessly between both ends of the paper discharge cylinder 19 and the pair of sprockets 22. As described above, the grippers 30 are provided on the connecting members (not shown) for connecting the pair of chains 23 to hold the leading end of the printed material and convey it. In FIG. 4, only two grippers 30 are shown, and the other grippers 30 are not shown.

  The length of the pair of chains 23 is an integral multiple of the circumferential length of the first and second impression cylinders 15 and 16, and the arrangement interval of the grippers 30 on the chain 23 is the first and second It is set to be equal to the circumferential length of the impression cylinders 15 and 16. Each gripper 30 is configured to open and close in synchronism with a gripper provided on the paper discharge cylinder 19 by a cam mechanism (not shown), receives a printed matter from the paper discharge cylinder 19, and rotates with the chain 23. After the printed material is conveyed, the printed material is discharged onto the paper discharge unit 32 by being opened by a cam mechanism (not shown).

  When the printed material is conveyed, only the leading edge of the printed material is conveyed by the gripper 30, so that the trailing edge of the printed material is conveyed in an unfixed state. For this reason, flickering of the printed matter occurs during this conveyance, which hinders the detection patch density measurement operation by the imaging means 60 described later. In order to prevent this, in this printing machine, a first suction roller 70 is provided on the front side of the paper discharge unit 32 to stabilize the conveyance state of the printed matter.

  The first suction roller 70 is constituted by a hollow roller having a large number of fine suction holes on its surface, and the hollow portion is connected to a vacuum pump (not shown). A gear 71 is attached to the end of the first suction roller 70. The gear 71 is connected to a gear attached to an end portion of the paper discharge cylinder 19 via idler gears 72 and 73. Thereby, the first suction roller 70 is rotationally driven in accordance with the passing speed of the gripper 30. For this reason, when the printed matter passes over the first suction roller 70, the printed matter is conveyed while being attracted to the surface of the first suction roller 70, and the printed matter flutters on the first suction roller 70. Does not occur.

  As described above, the plateless printing unit includes the ink jet ejection member 90 that ejects the ink jet and the second suction roller 74 for adsorbing the printed matter conveyed to a position facing the ink jet ejection member 90. .

  The second suction roller 74 is constituted by a hollow roller having a large number of fine suction holes on its surface, and the hollow portion is connected to a vacuum pump (not shown). The rotation shaft 75 of the second suction roller 74 and the rotation shaft 76 of the first roller 70 are connected by a winding belt 77, and the second suction roller 74 and the first suction roller 70 rotate in synchronization. It is configured as follows. As a result, the second suction roller 74 is also driven to rotate in accordance with the passing speed of the gripper 30. For this reason, when the printed matter passes over the second suction roller 74, the printed matter is conveyed while being attracted to the surface of the second suction roller 74, and the printed matter flutters on the second suction roller 74. Does not occur.

  The second suction roller 74 and the first suction roller 70 may be configured to rotate in synchronization via a gear or the like.

  FIG. 5 is a schematic view showing the arrangement of the ink head 91 in the ink jet ejection member 90.

  As shown in FIG. 5, the ink jet ejection member 90 includes a plurality of ink heads 91 that are configured by arranging a plurality of ink ejection nozzles linearly in the print width direction. Has been. Thereby, it can print with respect to the width direction whole region of printed matter. In this embodiment, only the ink jet ejection member 90 for one color is provided, but it is also possible to provide an ink jet ejection member 90 for multiple colors.

  The imaging means 60 is arranged in parallel with the suction roller 70 and illuminates the printed material on the suction roller 70, a pair of linear light sources 61, a pair of light collecting plates 62, folding mirrors 63 and 64, and a light collecting lens 65. CCD line sensor 66. The printed matter conveyed by the paper discharge mechanism including the paper discharge cylinder 19 and the chain 23 is illuminated by the pair of linear light sources 61 and photographed by the CCD line sensor 66. Based on the image data of the photographed printed matter, the printing position to be printed by the plateless printing means is calculated by the position calculating means 204 (see FIG. 6) described in detail later.

  FIG. 6 is a block diagram showing the main electrical configuration of the control means 200 in the printing apparatus according to the present invention.

  The control unit 200 sets an area setting unit 201 that sets a relative area of the second image printed by the plateless printing unit with respect to the first image printed by the plate printing unit, and is set by the region setting unit 201. A position storage unit 202 that stores a relative position for printing the second image with respect to the first image, a conveyance timing detection unit 203 that detects a conveyance timing of the printed material, and an imaging unit 60 based on the determined area. The obtained first image is subjected to image processing to calculate a relative position for printing the second image with respect to the first image, and the position calculated by the position calculation unit 204 and the conveyance of the printed matter. And a printing timing determination unit 205 that continuously determines the printing timing by the plateless printing unit during the printing operation based on the timing.

  FIG. 7 is a flowchart showing processing steps before printing.

  When printing is performed using the printing apparatus according to the present invention, the operator first prepares and designates first image data and second image data as image data 301 (see FIG. 6) for plate making. (Step S1). Here, the plateless printing means for printing the second image prints different images sequentially on the printed matter. The data of the second image is data having a plurality of images (for example, an image data group that is a set of image data), changeable character data (for example, a retail store name or address), or table data. is there. In addition, the second image data may be obtained by sequentially generating the corresponding numbers in order to give sequentially different serial numbers for each printed matter.

  Next, the position of the second image relative to the first image is designated by the area setting means 201 that sets the relative area of the second image relative to the first image (step S2). In order to designate the position of such an image, for example, data of the first image (for example, image data such as plate-making image data or PPF data created based on the plate-making image data) such as CRT is used. The image is displayed on the screen of the display device, and the position of the second image is designated by input means 302 (see FIG. 6) such as a mouse or a keyboard.

  FIG. 8 is a diagram showing the first image 100 displayed on the CRT and the second images A and B designated for the data of the first image.

  As a method for designating a region of the second image with respect to the first image, a method for designating a point serving as a reference point such as an end or center of the first image instead of adopting a method of designating directly with a mouse or the like Alternatively, a method of designating a position from a preset reference point by a numerical value or the like may be employed. Further, when creating the data of the first image, an area of the second image with respect to the first image may be set in advance. Note that other print information for designating an image (for example, when changing the second image for each of a plurality of sheets) can be designated.

  When the image position designation step (step S2) is completed, the relative position of the designated second image with respect to the first image is calculated and stored (step S3).

  FIG. 9 is a diagram illustrating a relationship between the second image A in FIG. 8 and a reference point P that serves as a reference for the position of the second image A. In FIG.

  As shown in FIG. 9, the end point of the second image A and the central portion of the reference point P are in a positional relationship separated by m in the vertical axis direction and n in the horizontal axis direction. Here, a reference mark M, which will be described in detail later, may be set as the reference point P, or the reference point P may be arbitrarily designated by the operator. Further, in the case of arbitrary designation, a frame line C for inserting the second image B is formed on the inside of the first image 100, and the position of the second image B is defined with reference to the frame line C. May be stored. At this time, the operator needs to specify in advance the position / shape of the frame line C, the color around the frame line C, and the like in the first image. In this way, when the reference point P is arbitrarily designated, the second image B and the reference point P can be arranged close to each other, and the shift between the first image and the second image can be reduced. Can be small. Then, in the subsequent process, the first image picked up by the image pickup means 60 is subjected to image processing to detect the reference point P, and the positions of the second images A and B are detected.

  Note that the reference point P may be set for two or more points as will be described in detail later. In this case, based on the positional relationship between two or more reference points P that are set in advance, it is possible to correct a shift due to the inclination or expansion / contraction of the area where the second images A and B are printed.

  When the processing step before printing shown in FIG. 7 is completed, printing is performed based on the relative area of the second image with respect to the first image designated by this processing step. FIG. 10 is a flowchart showing the processing steps when the second image is printed.

  An image of the printed matter on which the first image is printed by the printing apparatus according to the present invention is imaged by the imaging means 60 (see FIGS. 4 and 6) (step S11). At the time of this imaging, it may be set to read an image of the entire printed matter, or may be set to read only a predetermined range of the printed matter (a neighboring region where the reference point P is printed).

  In particular, when setting is made so as to read only a predetermined range, it is possible to obtain approximate position information of the conveyed printed matter by providing a rotary encoder on the cylinder of the plate printing means. Thereby, it can set so that the position of a predetermined range may be read. In addition to obtaining position information with an encoder, it is also possible to obtain position information by measuring timing pulses of a motor that rotates a cylinder or detecting a printed matter with an optical sensor.

  By setting so that only a predetermined range is read in this way, only a necessary image can be read. For this reason, the memory capacity and processing capability required for image processing can be reduced. Even when it is set to read an image of the entire printed matter, only a necessary image range may be processed.

  Next, the image data obtained in step S11 is subjected to image processing (step S12), and a reference point P is detected.

  As a method for detecting the reference point P, for example, a method of setting a reference mark M as shown in FIG. 9 as the reference point P (Japanese Patent Laid-Open No. 2003-11332) may be employed. In this case, the arrangement pattern of the pixels in the reference mark M is stored in advance. For example, in the case of the pixel row L shown in FIG. 9, the arrangement pattern is a pattern that is arranged in the order of 2 black pixels, 1 white pixel, 7 black pixels, 1 white pixel, and 2 black pixels from the left side of the drawing. Whether or not such an array pattern of the pixel row L is included in the image read by the imaging means 60 is calculated by shifting one pixel at a time in order to detect the reference mark M.

  In this embodiment, as shown in FIG. 8, it is set to print the detection patches 101 and 102 together with the first image in the printed material by the plate printing means. And these detection patches 101 and 102 are imaged by the imaging means 60, and the density | concentration of the detection patches 101 and 102 can be measured in the image processing process of step S12. The supply amount of dampening water or ink can be adjusted based on the density of the detection patches 101 and 102 measured in this way, and for example, details are disclosed in Japanese Patent Application Laid-Open No. 2002-355950 by the present applicant. A brief description will be given below.

  Specifically, the detection patch 101 and the detection patch 102 correspond to L areas divided in the width direction of the printed material (direction orthogonal to the printing direction by the printing press), as with each of the ink keys 2 described above. And each L is arranged in a state adjacent to each other. As these detection patches 101 and 102, those having a difference in density change after printing when the supply amounts of dampening water and ink are changed are employed. Of the detection patches 101 and 102, the detection patch 101 having a high dot area ratio is used, and the detection patch 102 having a low dot area ratio is used. First, in the step of performing printing a plurality of times by changing the supply amount of dampening water or ink, the water concentration corresponding to the concentration change amount of the detection patches 101 and 102 with respect to the change in dampening water is identified by multiple regression analysis, Next, the water density is calculated from the density of the detection patch 101 and the density of the detection patch 102 in the printed matter obtained by the trial printing, the ink adjustment amount is calculated using the water density, and the calculated water density and ink are calculated. The supply amount of dampening water and ink is adjusted based on the adjustment amount.

  In the above embodiment, the ink supply amount is adjusted by measuring the density of the detection patch. However, the ink supply amount is adjusted by measuring the color value of the detection patch or the print image. May be.

  After performing the image processing in step S12, based on the position of the reference mark M detected in step S12 and the relative position of the second image stored in step S3 with respect to the first image, the second in the printed matter. The position for printing the image is calculated (step S13).

  After that, secondly, the printing timing of the image is determined based on the printing position of the second image calculated in step S13 and the conveyance timing detected by the conveyance timing detection means 203 such as an encoder (step S14). Such a process of determining the printing timing is continuously executed while the printing is continued.

  In the printing apparatus according to the present invention, for the second image B, two reference points P serving as the reference of the second image in the first image are provided, and the second image B is based on the positional relationship of the reference points P. The shift due to the inclination or expansion / contraction of the area where the second image A is printed is corrected.

  FIG. 11 to FIG. 14 are explanatory diagrams sequentially showing steps for correcting the printing position of the second image B when two reference points P are set. FIG. 11 is an enlarged view showing the second image B in FIG. 8, and FIG. 12 is a diagram showing the positional relationship between the reference points P1, P2 and the second image B in the first image. FIGS. 13 and 14 are diagrams illustrating a process of correcting the printing position of the second image B so as to match the positional relationship of the first image with respect to the reference points P1 and P2.

  As shown in FIG. 12, the position of the reference point is set so that the reference point P1 corresponds to the upper left of the second image B and the reference point P2 corresponds to the lower right in the first image by the steps S1 to S3. To do. In step S <b> 11, the printed material on which the first image is actually printed by the plate printing unit is imaged by the imaging unit 60. In step S12, the captured image is processed. As shown in FIG. 13, points P11 and P12 corresponding to reference points P1 and P2 in an image (teacher image) to be evaluated are detected in an actually captured image (actual image). When detecting the points P11 and P12 of the real image corresponding to the reference points P1 and P2 in the teacher image thus detected, methods such as shaking processing and extracting vector components are used.

  Next, in step S13, two-dimensional offset information and rotation information are calculated from the deviations of the reference points P1 and P11 and the reference points P2 and P12. In this way, as shown in FIG. 14, the printing position of the second image B can be corrected and printed so as to match the positional relationship of the first image with respect to the reference points P1 and P2.

  In addition, the printed matter may be distorted due to a phenomenon such as paper stretching during printing. Even in such a case, it is possible to appropriately correct the printing position of the second image B with respect to the first image by increasing the reference points as shown in FIG. At this time, the distance between P11 and P13 (the distance between P14 and P12) may not match the distance between P1 and P3 (the distance between P4 and P2). In this case, the result of fitting the teacher images P1, P3, P2, and P4 to the rectangular areas of the actual images P11, P13, P12, and P14 by affine transformation or the like is printed.

  When the position of the reference point P is significantly deviated from the teacher image, processing such as printing stop, warning, and discarding is performed by setting a threshold value for the reference point P in advance. It is good. Alternatively, it may be determined that a detection error has occurred, and printing may be performed using the position of the previous reference point P.

  In the embodiment described above, offset printing is employed as the plate printing means, but intaglio printing, relief printing, or the like may be employed. Here, when offset printing is used, a waterless flat plate is particularly preferable. This is because the printed material does not get wet and the printing position is not easily displaced. Further, a pretreatment liquid may be applied before printing by the plateless printing means in order to improve ink placement by the plateless printing means.

  Further, as the plateless printing means, printing means by liquid toner development may be used in addition to the ink jet method. However, in consideration of the case where the previous plate printing is insufficiently dried, an ink jet method capable of non-contact printing is more preferable.

  In the above embodiment, the image picked up by the image pickup means 60 is used for adjusting the ink supply amount (color tone control) in plate printing and adjusting the printing position of the image in plateless printing. It may be used for color registration of each plate.

1 is a schematic view of a printing apparatus according to the present invention. 2 is a schematic side view of an ink supply device 20. FIG. 3 is a plan view of the ink supply device 20. FIG. 2 is a schematic side view showing a plateless printing unit and an imaging unit 60 together with a paper discharge mechanism such as a paper discharge cylinder 19; FIG. 3 is a schematic view showing the arrangement of ink heads 91 in the ink jet ejection member 90. FIG. It is a block diagram which shows the electric constitution of the control means 200 in the printing apparatus based on this invention. It is a flowchart which shows the process process before printing. It is a figure which shows the 1st image 100 displayed on CRT, and the 2nd images A and B designated with respect to the data of a 1st image. It is a figure which shows the relationship between the 2nd image A in FIG. 8, and the reference point P used as the reference | standard of the position of the 2nd image A. FIG. It is a flowchart which shows the process process during printing. It is explanatory drawing which shows the process of correct | amending the printing position of the 2nd image when the two reference points P are set. It is explanatory drawing which shows the process of correct | amending the printing position of the 2nd image when the two reference points P are set. It is explanatory drawing which shows the process of correct | amending the printing position of the 2nd image when the two reference points P are set. It is explanatory drawing which shows the process of correct | amending the printing position of the 2nd image when the two reference points P are set. It is explanatory drawing which shows the process of correct | amending the printing position of the 2nd image when the four reference points P are set.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 1st printing cylinder 12 2nd printing cylinder 13 1st blanket cylinder 14 2nd blanket cylinder 15 1st impression cylinder 16 2nd impression cylinder 17 Paper feed cylinder 18 Transfer cylinder 19 Paper discharge cylinder 20 Ink supply Device 21 Dampening water supply device 22 Sprocket 23 Chain 30 Gripper 31 Paper feed portion 32 Paper discharge portion 33 Plate feed portion 34 Plate feed portion 35 Image recording device 36 Image recording device 51 Ink source roller 52 Ink roller 53 Ink transfer roller 54 Ink key 55 Eccentric Cam 57 Pulse Motor 60 Imaging Unit 61 Linear Light Source 62 Condensing Plate 63 Folding Mirror 64 Folding Mirror 65 Condensing Lens 66 CCD Line Sensor 70 First Adsorption Roller 71 Gear 74 Second Adsorption Roller 75 Rotating Shaft 76 Rotating Shaft 77 Winding belt 90 Ink jet ejection member 91 Ink head 100 No. Image 101 detection patch 102 detection patch 200 control means 201 area setting means 202 position storage means 203 conveyance timing detection means 204 position calculation means 205 print timing determination means 301 image data 302 input means P reference point A second image B second Image C Frame M Reference mark L Pixel row

Claims (6)

Printing having a plate printing means for printing a first image using a printing plate and a plateless printing means for printing a second image without using a printing plate after printing the first image A device,
Area setting means for setting a relative area of the second image with respect to the first image;
Position storage means for storing a relative position for printing the second image with respect to the first image based on the area set by the area setting means;
Conveying means for conveying printing paper between the plate printing means and the plateless printing means;
A conveyance timing detection means for detecting a conveyance timing of the printing paper by the conveyance means;
An imaging unit that is located downstream in the transport direction of the plate printing unit and continuously captures a first image on the printing paper printed by the plate printing unit during a printing operation;
Position calculating means for performing image processing on the first image obtained by the imaging means and calculating a relative position for printing the second image with respect to the first image;
A printing timing determining means for continuously determining a printing timing by the plateless printing means during a printing operation based on the position calculated by the position calculating means and the conveyance timing of the printing paper by the conveying means;
A printing apparatus comprising: The printing apparatus according to claim 1,
The plateless printing means is a printing apparatus that sequentially prints different images on printing paper. The printing apparatus according to claim 1 or 2,
The plate printing means includes plate making means for forming an image on a printing plate on a plate cylinder based on image data for plate making prepared in advance.
The area setting means is a printing apparatus that performs area setting based on the image-making image data or image data related to the image-making image data before printing. The printing apparatus according to any one of claims 1 to 3,
A printing apparatus that determines at least one of an imaging region imaged by the imaging unit or an image processing region image-processed by the position calculation unit based on the relative position stored in the position storage unit. The printing apparatus according to any one of claims 1 to 4,
A printing apparatus that performs color tone control of a printed matter in the plate-based printing unit based on image data captured by the imaging unit. A plate printing mechanism for transferring the ink image formed on the printing plate to print the first common image on the printing paper, and a different number for each predetermined number of prints in the subsequent stage of the plate printing mechanism. A printing apparatus having a plateless printing mechanism capable of printing two images,
An image pickup means for picking up an image on a printing paper at a subsequent stage of the plate printing mechanism;
Obtaining the color value or color density of the image on the printing paper based on the image data imaged by the imaging means, adjusting the ink amount based on the color value or color density,
A printing apparatus that calculates a printing position of the second image on the printing paper based on image data picked up by the image pickup means.

Images