Print inspection device and printing press

Abstract

To provide a printed material inspection device and printing press that can properly check the density of printed colors and defects in the image. [Solution] The system comprises a feeding device that feeds a printed material in the same direction as the first area, which has a color bar for checking the density of the printed color printed on it, and a second area in which a pattern is printed on it, arranged in one direction; an imaging device that captures an image of the printed material being fed by the feeding device and generates an image; an illumination device that irradiates light into the imaging area of ​​the imaging device; and a processing device 44. The processing device 44 includes a feeding position derivation unit 440 that derives the feeding position of the printed material based on the amount the printed material is fed, an illumination control unit 441 that changes the light intensity of the illumination device according to the feeding position, and an imaging control unit 442 that executes the imaging operation of the imaging device. The illumination control unit 441 is capable of performing a second setting process that sets the light intensity of the illumination device to a first light intensity for the first area or a second light intensity for the second area, with the first light intensity being set higher than the second light intensity.

Description

Technical Field

[0005] , , , , ,

[0001] The present invention relates to a printed matter inspection apparatus for inspecting printed matter and a printing machine.

Background Art

[0002] As the above-mentioned printed matter inspection apparatus, for example, as disclosed in FIG. 1 of Patent Document 1, a pressure cylinder in which a sheet-fed printed matter is pressed against the circumferential surface by air blowing means, illumination means for irradiating light onto the sheet-fed printed matter pressed against the circumferential surface of the pressure cylinder, a camera for imaging a pattern of the sheet-fed printed matter illuminated at a certain illuminance by the illumination means, and a print quality determination means for determining the quality (presence or absence of defects) of printing from an image photographed by the camera. A sheet-fed printed matter inspection apparatus is known.

[0003] Also, for example, as disclosed in Patent Document 2, a technique of imaging a color bar printed on a sheet-fed paper which is a printing medium by a camera and detecting a density value by a density control device based on an image of this color bar is also known.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in a printed material inspection device such as the one disclosed in Patent Document 1, which uses an illumination means to irradiate the sheet-fed printed material with light and then uses a camera to image the sheet-fed printed material, when attempting to check the color density of the sheet-fed printed material in addition to inspecting the pattern, the constant illuminance meant that if the imaging environment was adjusted to match the pattern, the color bars could not be properly imaged, and if the imaging environment was adjusted to match the color bars, the pattern could not be properly imaged. As a result, there was a problem in that it was not possible to properly check either the pattern defects or the color density.

[0006] Therefore, in view of these circumstances, the present invention aims to provide a printed material inspection device and a printing press that can appropriately check the density of printed colors and defects in the image. [Means for solving the problem]

[0007] The printed material inspection apparatus of the present invention is A feeding device that feeds a printed material in the same direction as the first area, which has a color bar printed on it for checking the density of the printed color, and the second area, which has a picture printed on it, aligned in one direction. An imaging device that captures an image of the printed material being fed by the aforementioned feeding device and generates an image of the captured material, An illumination device that irradiates light onto the portion of the printed material that has reached the imaging area of ​​the imaging device, A processing unit, and The aforementioned processing apparatus is A feed position derivation unit configured to derive the feed position of the printed material relative to the imaging area based on the amount of the printed material fed by the feed device, A lighting control unit that changes the amount of light that the lighting device irradiates onto the printed material based on the feeding position derived by the feeding position derivation unit, The system comprises an imaging control unit that performs the imaging operation of the printed material by the imaging device, The lighting control unit is capable of performing a first setting process to set the light intensity of the lighting device to a first light intensity set to match the first area, and a second setting process to set the light intensity of the lighting device to a second light intensity set to match the second area. The first light intensity is set higher than the second light intensity.

[0008] When a color bar is imaged in a dark imaging area, the colors of the color bar are less likely to be reflected in the captured image. However, in the print inspection apparatus with the above configuration, the first setting process of the lighting control unit allows the light intensity of the lighting device to be set to a first light intensity that matches the first area. Therefore, the color bar can be imaged in a bright imaging area, creating an imaging environment in which the colors of the color bar are more likely to be reflected in the captured image.

[0009] Furthermore, when an image is captured in a brightly lit area, defects in the image are less likely to be visible in the captured image. However, in the printed material inspection apparatus with the above configuration, the second setting process of the lighting control unit allows the light intensity of the lighting device to be set to a second light intensity that matches the second area. This enables the image to be captured in a darkened area, creating an imaging environment in which defects in the image are more likely to be reflected in the captured image.

[0010] Therefore, the aforementioned print inspection device is designed to appropriately check the density of the printed colors and identify defects in the design.

[0011] In the printed material inspection apparatus of the present invention, The illumination control unit is configured to execute the first setting process before the feed position derivation unit determines that the first area has reached the imaging area, and to execute the second setting process before the feed position derivation unit determines that the second area has reached the imaging area. You may do so.

[0012] In this way, the imaging area can be brightened before the imaging device captures the first area, creating an imaging environment where the hues of the color bars are more easily reflected in the captured image. Furthermore, the imaging area can be darkened before the imaging device captures the second area, creating an imaging environment where defects in the pattern are more easily reflected in the captured image. This improves the accuracy of checking the density of printed colors and identifying defects in the pattern.

[0013] In the printed matter inspection apparatus of the present invention, the feeding device includes an inspection cylinder that can feed the printed matter while following the outer peripheral surface, and a rotary encoder that detects the rotational phase of the inspection cylinder, and the feeding position derivation unit is configured to derive the feeding position based on the rotational phase of the inspection cylinder detected by the rotary encoder. It may be configured in this way.

[0014] Even when the printed matter is fed by the inspection cylinder in this way, after obtaining the rotational phase representing the operation amount of the inspection cylinder by the rotary encoder, the feeding position of the printed matter can be derived by the feeding position derivation unit. Therefore, the light amount of the lighting device can be changed according to the first area and the second area, and the appropriateness of confirming the density of the printed color and the defect of the pattern can be enhanced.

[0015] The printing machine of the present invention includes any one of the above-described printed matter inspection apparatuses, and performs the imaging and the irradiation on the cylinder provided most downstream in the feeding direction of the printed matter. It is configured in this way.

[0016] Even in the printing machine having the above configuration, by the first setting process of the lighting control unit, the light amount of the lighting device is set to the first light amount adjusted to the first area, and an imaging environment in which the color tone of the color bar is easily reflected in the captured image can be created. Also, by the second setting process of the lighting control unit, the light amount of the lighting device is set to the second light amount adjusted to the second area, and an imaging environment in which the defect occurring in the pattern is easily reflected in the captured image can be created. Therefore, the density of the printed color and the defect of the pattern can be appropriately confirmed.

Advantages of the Invention

[0017] As described above, according to the printed matter inspection apparatus and the printing machine of the present invention, it is possible to achieve an excellent effect of appropriately confirming the density of the printed color and the defect of the pattern.

Brief Description of the Drawings

[0018] [Figure 1] FIG. 1 is a schematic diagram of a printing machine including a printed matter inspection device according to an embodiment of the present invention. [Figure 2] FIG. 2 is an enlarged view of a main part of the printed matter inspection device according to the embodiment. [Figure 3] FIG. 3 is a configuration block diagram of a processing device of the printed matter inspection device according to the embodiment. [Figure 4] FIG. 4 is an explanatory diagram of a printed matter of the printed matter inspection device according to the embodiment. [Figure 5] In FIG. 5, (a) is an explanatory diagram of the timing of starting to feed a printed matter by an inspection cylinder, (b) is an explanatory diagram of a state where a first area of the printed matter fed by the inspection cylinder has reached an imaging area, and (c) is an explanatory diagram of a state where a second area of the printed matter fed by the inspection cylinder has reached the imaging area. [Figure 6] In FIG. 6, (a) is a diagram showing the relationship between the density of a printed color and the RGB values of 256 gradations when the first area is imaged in a dark state, and (b) is a diagram showing the relationship between the density of the printed color and the RGB values of 256 gradations when the first area is imaged in a bright state.

Embodiments for Carrying Out the Invention

[0019] Hereinafter, a printing machine including a printed matter inspection device according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0020] The printing machine 1 of the present embodiment is a sheet-fed printing machine, and as shown in FIG. 1, it includes a paper feeding unit (not shown) for supplying sheet-fed paper to be printed, a plurality of printing units 2 for performing printing processing in a plurality of colors on the sheet-fed paper sent out from the paper feeding unit, a paper discharging unit 3 for discharging a printed matter which is the sheet-fed paper subjected to the printing processing by the plurality of printing units 2, and a printed matter inspection device 4 for inspecting the printing state of the printed matter.

[0021] As shown in Figure 4, the printed material P produced by the printing press 1 according to this embodiment has a first area P1 on which a color bar P10, which serves as a color tone measurement mark for checking the density of the printed color, is printed, and a second area P2 on which a pattern P20 is printed, with the first area P1 and the second area P2 aligned in one direction. Arrow A in Figure 4 indicates the feeding direction, which will be described later.

[0022] Color bar P10 includes areas such as P100 for checking the density of cyan (C), magenta (M), yellow (Y), and black (K). Each area P100 is a so-called solid patch.

[0023] Furthermore, in the first area P1, margins P11 are formed on both sides of the color bar P10 in the aforementioned one direction.

[0024] As shown in Figure 1, the printed material inspection device 4 is a device for feeding printed material P, and includes a feeding device 40 that feeds the printed material P with the first area at the front, a movement amount detection device 41 that detects the amount of movement of the feeding device 40, an imaging device 42 that captures an image of the printed material P as it is being fed by the feeding device 40 and generates an image, an illumination device 43 that irradiates light onto the portion of the printed material that has reached the imaging area of ​​the imaging device 42, and a processing device 44 (see Figure 3) configured using a computer.

[0025] In the following description, the direction in which the feed device 40 feeds the printed material P will be referred to as the feed direction. In this embodiment, the feed direction is the same direction as arrow A in Figure 4, and is the same direction as the direction in which the first area P1 and the second area P2 are aligned.

[0026] The feed device 40 has an inspection cylinder 400 that is cylindrical and configured to rotate about its own central axis. The inspection cylinder 400 is a transport cylinder. In the printing press 1 of this embodiment, the impression cylinder provided in the printing unit 2, which is the furthest downstream in the feeding direction of the printed material P, also serves as the inspection cylinder 400.

[0027] As shown in Figures 5(a), 5(b), and 5(c), the printed material P is held by the inspection cylinder 400 at the end of the first area P1 in the feeding direction, and is wound around the inspection cylinder 400 and fed by the rotation of the inspection cylinder 400 with the first area P1 at the front in the feeding direction. At this time, the printed material P is aligned with the outer surface of the inspection cylinder 400 by the air blown by the air blowing means 45 (see Figure 2). Note that in Figures 5(a), 5(b), and 5(c), only one printed material P is shown for the sake of clarity.

[0028] The motion amount detection device 41 in this embodiment is composed of a rotary encoder attached to the inspection cylinder 400. The motion amount detection device 41 is configured to detect and output the rotational phase of the inspection cylinder 400.

[0029] The imaging device 42 is located outside the printing unit 2 and consists of a camera fixed to the upper part of the paper discharge unit 3. The printing unit 2 has a slit-shaped window (not shown) for imaging the printed material P being fed by the inspection cylinder 400 with the imaging device 42.

[0030] The imaging device 42 is composed of a so-called line camera. Therefore, the imaging area S of the imaging device 42 is set to extend linearly in a direction perpendicular to the aforementioned one direction and to include one end and the other end of the printed material P in a direction perpendicular to the aforementioned one direction.

[0031] As shown in Figure 2, the lighting device 43 is located inside the printing unit 2 and includes a light-emitting unit 430 configured to emit light when power is supplied from a power source (not shown), and a reflecting unit 431 that reflects the light generated by the light-emitting unit 430 into the imaging area S.

[0032] The light-emitting unit 430 in this embodiment is composed of LEDs. The light-emitting unit 430 is configured to continue emitting light by receiving power supplied from the power supply while imaging is being performed by the imaging device 42.

[0033] Furthermore, the amount of light generated by the light-emitting unit 430 is configured to increase or decrease in accordance with the voltage of the power supply. Therefore, when the power supply voltage increases, the amount of power supplied to the light-emitting unit 430 from the power supply increases, the amount of light generated by the light-emitting unit 430 increases, the illuminance of the printed material P increases, and as a result, the brightness of the image captured by the imaging device 42 also increases.

[0034] On the other hand, when the power supply voltage drops, the amount of power supplied to the light-emitting unit 430 from the power supply decreases, reducing the amount of light generated by the light-emitting unit 430. As a result, the illuminance of the printed material P decreases, and consequently, the brightness of the image captured by the imaging device 42 also decreases.

[0035] As shown in Figure 3, the processing device 44 includes a feed position derivation unit 440 configured to acquire the amount of movement of the feed device 40 output from the movement amount detection device 41 and derive the feed position of the printed material relative to the imaging area S; an illumination control unit 441 that changes the amount of light of the light-emitting unit 430 according to the feed position derived by the feed position derivation unit 440; an imaging control unit 442 that controls the imaging operation of the imaging device 42; a density confirmation unit 443 that checks the color density of each area P100 of the color bar P10 based on the image of the first area P1 of the printed material obtained by the imaging operation of the imaging device 42; and a pattern confirmation unit 444 that checks the pattern P20 (specifically, defects occurring in the pattern P20) based on the image of the second area P2 of the printed material obtained by the imaging operation of the imaging device 42.

[0036] The feed position derivation unit 440 is configured to acquire the amount of movement of the feed device 40 output from the amount of movement detection device 41 and to derive the arrival position of the printed material P that has reached the imaging area S based on the amount of movement.

[0037] As described above, the motion amount detection device 41 of this embodiment is composed of a rotary encoder and is configured to detect and output the rotation phase of the inspection cylinder 400. Therefore, the feed position derivation unit 440 is configured to acquire the rotation phase of the inspection cylinder 400 output from the rotary encoder and to derive the feed position of the printed material P based on this rotation phase.

[0038] More specifically, the feed position derivation unit 440 has the feed amount of the printed material P (feed position of the printed material P) associated with each rotation phase of the inspection cylinder 400, and when the rotation phase is obtained from the motion amount detection device 41, the feed position of the printed material P is derived based on the obtained rotation phase.

[0039] Therefore, the feed position extraction unit 440 can also determine, based on the extracted feed position of the printed material P, whether the printed material P is in a state before reaching the imaging area S (see Figure 5(a)), whether the first area P1 of the printed material P has reached the imaging area S (see Figure 5(b)), or whether the second area P2 of the printed material P has reached the imaging area S (see Figure 5(c)).

[0040] The lighting control unit 441 is configured to perform the following processes: acquiring the feed position of the printed material P derived by the feed position derivation unit 440; comparing the acquired feed position of the printed material P with a first position set as the timing for setting the light intensity of the lighting device 43 to a light intensity suitable for imaging the first area P1 (first light intensity); and, if the feed position of the printed material P and the first position match, setting the light intensity of the lighting device 43 to the first light intensity; and, if the feed position of the printed material P and the second position match, setting the light intensity of the lighting device 43 to the second light intensity.

[0041] The illumination control unit 441 is preferably configured such that, compared to the brightness of the image obtained when the imaging device 42 images the printed material P with the illumination device 43 set to a first light intensity, the brightness of the image obtained when the imaging device 42 images the printed material P with the illumination device 43 set to a second light intensity is increased by 20% to 30%, preferably 25%.

[0042] The lighting control unit 441 is configured to perform a first setting process, which involves reading a first voltage value necessary to set the light output of the lighting device 43 to a first light output, and setting the voltage of the power supplied from the power supply to the lighting device 43 to match the first voltage value. This configuration allows the light output of the lighting device 43 to be increased.

[0043] Furthermore, the lighting control unit 441 is configured to perform a second setting process, which involves reading a second voltage value necessary to set the light intensity of the lighting device 43 to a second light intensity, and setting the voltage of the power supplied from the power supply to the lighting device 43 to match the second voltage value. This configuration allows the light intensity of the lighting device 43 to be reduced.

[0044] Furthermore, in the lighting control unit 441, it is sufficient that a first voltage value required to set the light intensity of the lighting device 43 to a first light intensity, and a second voltage value required to set the light intensity of the lighting device 43 to a second light intensity, are pre-set as specified values.

[0045] When the first area P1 (color bar P10) of the printed material P printed on each sheet of paper is imaged by the imaging device 42 under low illumination conditions (dark conditions), the color of the color bar P10 is less likely to be reflected in the image obtained from the imaging device 42. However, when the first area P1 (color bar P10) of the printed material is imaged by the imaging device 42 under high illumination conditions (bright conditions), the color of the color bar P10 (area P100) is more likely to be reflected in the image obtained from the imaging device 42.

[0046] Furthermore, when the image of the second area P2 of the printed material P printed on each sheet of paper is captured by the imaging device 42 under high illumination conditions (bright conditions), a phenomenon called overexposure is more likely to occur in the captured image obtained from the imaging device 42, making it difficult to reflect defects occurring in the image P20. However, when the second area P2 of the printed material is captured by the imaging device 42 under low illumination conditions (dark conditions), defects occurring in the image P20 are more likely to be reflected in the captured image obtained from the imaging device 42.

[0047] Thus, the purpose for which the captured images obtained by the imaging device 42 are used differs between the first area P1 and the second area P2, and the appropriate illuminance differs for each purpose.

[0048] Here, the first position is set to the position of the printed material P before the first area P1 reaches the imaging area S. Therefore, the illumination control unit 441 is configured to execute the first setting process before the first area P1 of the printed material P reaches the imaging area S.

[0049] Furthermore, the second position is set to the position of the printed material P before the second area P2 reaches the imaging area S (for example, the state in which the margin P11 located on the second area P2 side of the color bar P10 in one direction has reached the imaging area S). Therefore, the illumination control unit 441 is configured to execute the second setting process before the second area P2 of the printed material P reaches the imaging area S.

[0050] The imaging control unit 442 is configured to perform imaging operations continuously at predetermined time intervals.

[0051] The density confirmation unit 443 is configured to perform a process to determine the color density of the printed material P based on the image of the color bar P10 (area P100) captured by the imaging device 42.

[0052] The density confirmation unit 443 is configured to acquire RGB values ​​from the captured image obtained by the imaging device 42 and to derive the color density of the printed material P (area P100) based on these RGB values.

[0053] Furthermore, the density confirmation unit 443 of this embodiment is configured to perform the following processes: deriving the density of cyan based on RGB values ​​obtained from the cyan region of the captured image; deriving the density of magenta based on RGB values ​​obtained from the magenta region of the captured image; deriving the density of yellow based on RGB values ​​obtained from the yellow region of the captured image; and deriving the density of black based on RGB values ​​obtained from the black region of the captured image.

[0054] The pattern verification unit 444 is configured to perform a process to check for defects in the pattern P20 based on the image of the pattern P20 in the second area P2 captured by the imaging device 42.

[0055] The pattern verification unit 444 is configured to perform a process to determine whether or not there is a defect by using, for example, a master image which is an image of a printed material P in a normal state and an inspection image which is an image of a printed material P for inspection, and by comparing the pixels of the inspection image with the corresponding pixels of the master image, and to perform this process for each pixel of the inspection image.

[0056] The configuration of the printing press 1 according to this embodiment is as described above. Next, the operation of the printing press 1 will be explained.

[0057] When the printing press 1 performs the printing process on the sheets of paper, the printed sheets (printed material P) processed by each printing unit 2 reach the inspection cylinder 400 of the downstream printing unit 2 and are fed by the inspection cylinder 400.

[0058] Then, while the printed material is being fed by the inspection cylinder 400, the printed material P being fed by the inspection cylinder 400 is imaged by the imaging device 42, and an image is obtained.

[0059] At this time, the light intensity of the illumination device 43 is set to the first light intensity by the illumination control unit 441 before the first area P1 of the printed material P reaches the imaging area S of the imaging device 42. As a result, the color of the color bar P10 is more easily reflected in the image captured by the imaging device 42 when it captures the first area P1, thereby improving the accuracy of the color density determination by the density confirmation unit 443.

[0060] Furthermore, when the color bar P10 is captured with the imaging area S in a dark state, the resulting image, as shown in Figure 6(a), shows that the range of colors obtainable within the predetermined density range Vs1 to Vs2, which is set as a commonly used density range in the printing press 1, is Vm1 to Vm2. However, when the color bar P10 is captured with the imaging area S in a bright state, as shown in Figure 6(b), the overall color density increases without changing the RGB values. As a result, the range of Vs1 to Vs2, which is set as a predetermined density range, can be made to correspond to the part with a gradual change, thereby expanding the range of colors obtainable within that range to Vm3 to Vm4.

[0061] Note that the ranges for Vm1-Vm2 and Vs1-Vs2 differ depending on whether you're using cyan, magenta, yellow, or black.

[0062] Furthermore, the light intensity of the illumination device 43 is set to the second light intensity by the illumination control unit 441 before the second area P2 of the printed material P reaches the imaging area S of the imaging device 42. As a result, defects occurring in the pattern P20 are more easily reflected in the image captured by the imaging device 42 when it captures the second area, thereby improving the accuracy of the pattern confirmation unit 444's confirmation of defects occurring in the pattern P20.

[0063] Thus, the printing press 1 of this embodiment is designed to appropriately check the color density and identify any defects in the image.

[0064] The image captured by the imaging device 42 of the first area P1 is used by the density confirmation unit 443 to confirm the density of the printed color, and the image captured by the imaging device 42 of the second area P2 is used by the pattern confirmation unit 444 to confirm defects in the pattern P20.

[0065] As described above, when the color bar P10 is imaged while the imaging area S is dark, the colors of the color bar P10 are less likely to be reflected in the captured image. However, in the printing press 1 of this embodiment, the first setting process of the lighting control unit 441 allows the light intensity of the lighting device 43 to be set to a first light intensity that matches the first area P1. Therefore, the color bar P10 can be imaged while the imaging area S is bright, creating an imaging environment in which the colors of the color bar P10 are more likely to be reflected in the captured image.

[0066] Furthermore, when the second area P2 is imaged while the imaging area S is bright, defects occurring in the pattern P20 are less likely to be captured in the image. However, in the printed material inspection apparatus 4 of this embodiment, the second setting process of the illumination control unit 441 allows the light intensity of the illumination device 43 to be set to a second light intensity that matches the second area P2. Therefore, the second area P2 can be imaged while the imaging area S is dark, creating an imaging environment in which defects occurring in the pattern P20 are more likely to be reflected in the image.

[0067] Therefore, the printing press 1 can achieve the excellent effect of being able to properly check the color density and the defects in the image.

[0068] Furthermore, in the printing press 1 of this embodiment, the lighting control unit 441 is configured to execute a first setting process before the feed position guide unit 440 determines that the first area has reached the imaging area, and to execute a second setting process before the feed position guide unit 440 determines that the second area has reached the imaging area. As a result, the imaging area S can be brightened before the imaging device 42 captures the first area P1, creating an imaging environment in which the color of the color bar P10 is easily reflected in the captured image. Additionally, the imaging area S can be darkened before the imaging device 42 captures the second area P2, creating an imaging environment in which defects occurring in the pattern P20 are easily reflected in the captured image. This improves the accuracy of checking color density and identifying defects in the pattern.

[0069] Furthermore, although the printing press 1 of this embodiment has a feed device 40 composed of an inspection cylinder 400, even when the printed material is fed by the inspection cylinder 400 in this manner, the rotary encoder can be used to obtain the rotational phase representing the amount of movement of the inspection cylinder 400, and the feed position of the printed material can be derived by the feed position derivation unit 440. As a result, the light intensity of the illumination device 43 can be changed to match the first area and the second area, thereby improving the accuracy of checking color density and defects in the image.

[0070] It should be noted that the printed material inspection apparatus and printing press according to the present invention are not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the present invention.

[0071] Although the printed material inspection device 4 of the above embodiment was described with the example of being incorporated into the printing press 1, it may also be configured to be retrofitted to an existing printing press 1, for example.

[0072] Although the printing press 1 in the above embodiment was configured to perform printing on sheet paper, it may also be configured to perform printing on roll paper, for example.

[0073] The print inspection device 4 in the above embodiment targeted printed materials sent by the printing unit 2, but it may also target printed materials sent by a coater unit that applies a coating to the printed surface of the printed material. Alternatively, it may target printed materials sent by a dedicated inspection unit.

[0074] In the above embodiment, the printing press 1 was configured to change the brightness of the captured image by changing the total amount of light from the light-emitting unit 430. However, if the light-emitting unit 430 is composed of a large number of LEDs, it may be configured to change the brightness of the captured image by changing the number of LEDs that emit light.

[0075] Furthermore, the printing press 1 may be configured to change the brightness of the captured image by changing the direction of the optical axis of the light-emitting unit 430.

[0076] Although not specifically mentioned in the description of the lighting control unit 441 in the above embodiment, the lighting control unit 441 may be configured to set the light intensity of the light-emitting unit 430 to an even lower light intensity than the light intensity set by the second light intensity when, for example, the margin of the second area of ​​the printed material reaches the imaging area.

[0077] Although not specifically mentioned in the description of the lighting control unit 441 in the above embodiment, the lighting control unit 441 may be configured to partially change the light intensity of the light-emitting unit 430 according to the color of each area P100 of the color bar P10.

[0078] Although it has been explained that the second light intensity used by the lighting control unit 441 in the above embodiment is a predetermined value, for example, the lighting control unit 441 may be configured to automatically set the second light intensity according to the pattern of the printed material P captured by the imaging device 42.

[0079] In the above embodiment, the printing press 1 was configured to feed the printed material P by an inspection cylinder 400, but it may also be configured to feed the printed material by a conveyor, for example.

[0080] Although not specifically mentioned in the description of the printing press 1 of the above embodiment, the window portion may be configured to have an opening / closing cover that opens and closes the opening.

[0081] Although not specifically mentioned in the description of the printing press 1 of the above embodiment, the pattern confirmation unit 444 may be configured to check for defects in the entire second area P2 of the printed material P based on the captured image of the second area P2 obtained by the imaging device 42 performing an imaging operation. In this configuration, defects such as dirt occurring around the pattern P20 can also be confirmed. [Explanation of Symbols]

[0082] 1…Printing machine, 2…Printing unit, 3…Paper discharge unit, 4…Print inspection device, 40…Feeding device, 41…Motion amount detection device, 42…Imaging device, 43…Illumination device, 44…Processing device, 430…Light-emitting unit, 440…Feed position guide unit, 441…Illumination control unit, 442…Imaging control unit, 443…Density confirmation unit, 444…Pattern confirmation unit, A…Arrow, P…Printed material, P1…First area, P10…Color bar, P100…Area, P2…Second area, S…Imaging area

Claims

1. A feeding device that feeds a printed material in the same direction as the first area, which has a color bar printed on it for checking the density of the printed color, and the second area, which has a picture printed on it, aligned in one direction. An imaging device that captures an image of the printed material being fed by the aforementioned feeding device and generates an image of the captured material, An illumination device that irradiates light onto the portion of the printed material that has reached the imaging area of ​​the imaging device, A processing unit, and The aforementioned processing apparatus is A feed position derivation unit configured to derive the feed position of the printed material relative to the imaging area based on the amount of the printed material fed by the feed device, A lighting control unit that changes the amount of light that the lighting device irradiates onto the printed material based on the feeding position derived by the feeding position derivation unit, The system comprises an imaging control unit that performs the imaging operation of the printed material by the imaging device, The lighting control unit is capable of performing a first setting process to set the light intensity of the lighting device to a first light intensity set to match the first area, and a second setting process to set the light intensity of the lighting device to a second light intensity set to match the second area. The first light intensity is set higher than the second light intensity. Print inspection device.

2. The lighting control unit is configured to execute the first setting process before the feed position derivation unit determines that the first area has reached the imaging area, and to execute the second setting process before the feed position derivation unit determines that the second area has reached the imaging area. The printed material inspection apparatus according to claim 1.

3. The aforementioned feeding device is An inspection cylinder capable of feeding the aforementioned printed material along its outer surface, The system includes a rotary encoder for detecting the rotational phase of the inspection cylinder, The feed position deriving unit is configured to derive the feed position based on the rotational phase of the inspection cylinder detected by the rotary encoder. The printed material inspection apparatus according to claim 2.

4. A printed material inspection apparatus according to any one of claims 1 to 3, The imaging and illumination are performed on the cylinder located at the furthest downstream in the feeding direction of the printed material. printing machine.

Images