Printing mark registration device for printed matter detection

Abstract

The utility model discloses a printing mark registration device for printed matter detection, which belongs to the technical field of printing detection and comprises a plurality of printing units mounted in a case, each printing unit corresponds to printing of one color layer, the plurality of printing units are sequentially arranged in the case, and the printing units are arranged in the case. The printing unit is used for printing different color layers on paper in sequence, the printing unit comprises a plate cylinder, a rubber cylinder and an impression cylinder, the plate cylinder is provided with plate bodies, the printing unit further comprises a registration marking unit and a photoelectric scanner, the registration marking unit is composed of registration marking pieces arranged on the plate bodies, and the photoelectric scanner is arranged on the rubber cylinder. Each registration marking piece comprises a circular frame and a straight line part connected to the outer side of the circular frame, the arrangement of the circular frames makes it more visual to judge whether the two circular frames coincide or not, the registration state can be judged in an auxiliary mode, a new detection dimension is provided, registration detection is more visual and accurate, and the accuracy of registration detection is improved. And subsequent manual detection and judgment of the registration condition are facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of printing detection, in particular to a printing mark registration device for printed product detection. Background Art

[0002] Registration in the printing industry refers to the accuracy of the overlap of the positions of any two color images during the multi-color overprinting process. Specifically, registration is achieved by controlling the printing plate of each color to ensure that each part of the printed pattern can be accurately printed on the required substrate area. This is one of the important indicators of printing quality, especially in two-color and multi-color printing. In order to achieve accurate registration, a series of measures are usually taken, such as making dots, circles, crosses or other registration marks on the edges or blank spaces of the printing plate, and the printer will accurately trace these marks onto other corresponding sub-plates so that each plate can be calibrated during the printing process to ensure that each plate color is aligned with the other plates.

[0003] At present, for some printed materials with extremely high requirements for registration accuracy, such as cigarette packaging paper, existing registration marks and detection devices are difficult to accurately capture tiny registration deviations. Marks with simple geometric shapes such as cross lines and squares are mostly based on single geometric shape features for registration detection. When judging the registration situation, it is mainly based on rough visual overlap, such as only looking at the overlap of the cross lines. Such marks are relatively insensitive to tiny registration deviations and may not accurately reflect problems in printing with high precision requirements. Moreover, it is even more difficult to observe the registration situation during subsequent manual random inspections. Utility Model Content

[0004] The embodiment of the present utility model provides a printing mark registration device for printed product detection to solve the above-mentioned technical problems.

[0005] The embodiment of the utility model adopts the following technical solution: it includes multiple printing units installed inside the chassis, each of the printing units corresponds to the printing of a color layer, and the multiple printing units are arranged in sequence in the chassis for printing different color layers on paper in sequence. The printing units include a printing plate roller, a rubber roller and a pressing roller, and the printing plate roller is provided with a printing plate body, and also includes a registration mark unit and a photoelectric scanner. The registration mark unit is composed of a registration mark member arranged on each of the printing plate bodies, and each of the registration mark members includes a circular frame and a straight line portion connected to the outside of the circular frame. The diameters of the circular frames of the registration marks arranged in sequence inside the chassis gradually increase or decrease, and when two adjacent circular frames are concentric, one end of the straight line portion connected on the inner circular frame is aligned with the edge of the outer circular frame, which indicates printing registration. The photoelectric scanner is arranged at the downstream end of each printing unit for collecting images of the registration mark members on the paper after printing by adjacent printing units.

[0006] Furthermore, when the plurality of circular frames are concentric, the plurality of straight line portions are offset from each other, making it easier to observe whether they are aligned.

[0007] Furthermore, it also includes a controller, and the chassis is also provided with an alarm corresponding to each printing unit. When the controller receives a signal from the photoelectric scanner that a registration error has occurred, it controls the alarm to issue an alarm to remind personnel where the registration problem of the printing unit has occurred.

[0008] Furthermore, the chassis is provided with a transverse roller adjustment mechanism and a longitudinal roller adjustment mechanism corresponding to each printing unit, and the transverse roller adjustment mechanism and the longitudinal roller adjustment mechanism are both electrically connected to the controller, so as to facilitate timely adjustment of the printing unit.

[0009] Furthermore, the photoelectric scanner is installed inside the chassis via a three-dimensional pan-tilt platform, so that the photoelectric scanner maintains a relatively stable posture to detect the registration mark.

[0010] Furthermore, a coding mechanism electrically connected to the controller is installed on the inner wall of the chassis. The coding mechanism is installed at the downstream end of each printing unit and is used to perform coding marking when the registration is inaccurate, so as to facilitate subsequent retrieval of products with inaccurate registration.

[0011] At least one of the above technical solutions adopted in the embodiment of the present utility model can achieve the following beneficial effects:

[0012] In the present invention, the setting of the circular frame makes it more intuitive to judge whether two circular frames overlap. When the straight line portion is not accurately connected to the adjacent circular frame, for example, it exceeds or does not reach another circular frame, it is known that there is a deviation in the center positions of the two circular frames, that is, it is judged that there is a problem with the registration. The connection between the straight line portion and the circular frame is used to assist in judging the registration status, providing a new detection dimension, making the registration detection more intuitive and accurate, and can also keenly perceive some extremely small registration deviations, and also facilitates subsequent manual detection and judgment of the registration status. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0014] Figure 1 It is a schematic diagram of the three-dimensional structure of the utility model;

[0015] Figure 2 A schematic diagram of the cross-sectional structure provided by the utility model;

[0016] Figure 3 A schematic diagram of the structure of the registration mark provided by the utility model on the printing plate body;

[0017] Figure 4 This is a schematic diagram of the alignment of multiple registration marking members in the present invention;

[0018] Figure 5 This is a schematic diagram of a case where multiple registration marking elements in the present invention are not registered;

[0019] Figure 6 This is a system block diagram provided by the utility model.

[0020] Reference numerals

[0021] Chassis 1, printing unit 2, plate cylinder 21, rubber cylinder 22, impression cylinder 23, printing plate body 24, registration mark 3, circular frame 31, straight part 32, photoelectric scanner 4, controller 5, alarm 51, transverse plate roller adjustment mechanism 6, longitudinal plate roller adjustment mechanism 7, three-dimensional pan-tilt platform 8, and inkjet coding mechanism 9. DETAILED DESCRIPTION

[0022] To make the purpose, technical solutions, and advantages of the present invention more clear, the following will provide a clear and complete description of the technical solutions of the present invention in conjunction with specific embodiments of the present invention and the corresponding drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are also within the scope of protection of the present invention.

[0023] The technical solutions provided by various embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0024] The embodiment of the present invention provides a printing mark registration device for printed product detection, including a plurality of printing units 2 installed inside a chassis 1, each printing unit 2 corresponding to the printing of a color layer, and the plurality of printing units 2 are arranged in sequence in the chassis 1 for printing different color layers on paper in sequence, and the printing unit 2 includes a plate cylinder 21, a rubber cylinder 22 and an impression cylinder 23, and a printing plate body 24 is provided on the plate cylinder 21. Taking four-color printing as an example, the number of printing units 2 is four. When printing, the printing plate body 24 with graphics is installed on the plate cylinder 21. The printing plate The roller 21 first contacts the ink roller to obtain ink, and then transfers the ink of the image and registration mark to the rubber roller 22. The elasticity of the rubber roller 22 can better adapt to the unevenness of the paper surface and make the ink transfer more uniform. The impression roller 23 provides printing pressure to make the paper and the rubber roller 22 closely contact, thereby realizing the transfer of ink from the rubber roller 22 to the paper and completing the printing. In order to ensure that the patterns on each printing unit 2 can accurately overlap, printing registration is required during the printing process. Therefore, a registration mark unit and a photoelectric scanner 4 for detecting the registration status are also included;

[0025] Specifically, the registration mark unit is composed of a registration mark member 3 provided on each printing plate body 24, and each registration mark member 3 includes a circular frame 31 and a straight portion 32 connected to the outside of the circular frame 31, and the diameters of the circular frames 31 of the registration mark members 3 sequentially provided inside the chassis 1 gradually increase or decrease, and when two adjacent circular frames 31 are concentric, one end of the straight portion 32 connected on the inner circular frame 31 is aligned with the edge of the outer circular frame 31, which indicates printing registration. After the paper passes through the printing unit 2 at the upstream end of the chassis 1 and is printed in one color, a set of registration marks is marked on the paper, that is, a circular shaped frame 31 and a straight portion 32 connected to the outer edge of the circular frame 31. As the paper enters the next printing unit 2 to be printed in another color, the registration mark on the printing plate body 24 will be located inside or outside the previous registration mark. For example, from the input end to the output end of the chassis 1, the diameter of the circular frame 31 in the registration mark part 3 on the printing unit 2 gradually increases, such as the diameter is 2cm, 4cm, 6cm, and the length of the straight portion 32 is equal, and its length is the difference between the diameters of the two adjacent circular frames 31. If it increases, the downstream registration mark will be located inside the upstream registration mark, that is, the downstream circular frame 31 is located inside the upstream circular frame 31. Figure 4 As shown, when two adjacent circular frames 31 are concentric, one end of the straight portion 32 on the inner circular frame 31 is connected to the edge of the outer circular frame 31, indicating that the registration is accurate at this time. Figure 5 As shown, when there is a problem with registration, the adjacent circular frames 31 are not concentric, and the straight portion 32 is not accurately connected to the adjacent circular frame 31, and may exceed or fail to reach another circular frame 31. The connection between the straight portion 32 and the circular frame 31 is used to assist in determining the registration status, providing a new detection dimension, making registration detection more intuitive and accurate, and also facilitating subsequent personnel to visually determine the printing registration status during spot checks.

[0026] The photoelectric scanner 4 is arranged at the downstream end of each printing unit 2, and is used to collect the image of the overprint mark on the paper after printing by the adjacent printing unit 2. After the paper passes through the printing unit 2 and is printed with the overprint mark, the overprint mark is collected by the photoelectric scanner 4, and the registration is judged in combination with the two adjacent overprint marks. In addition, it also includes a controller 5. The chassis 1 is also provided with an alarm 51 corresponding to the printing unit 2. When the controller 5 receives the overprint error detected by the photoelectric scanner 4, it controls the alarm 51 to issue an alarm. The alarm 51 can be a warning light and / or a buzzer alarm. When the photoelectric scanner 4 detects an overprint error, the controller 5 controls the corresponding alarm 51 to issue an alarm prompt to remind personnel which specific stage of the printing unit 2 has a problem, so as to facilitate subsequent corrections.

[0027] Preferably, the chassis 1 is provided with a transverse plate roller adjustment mechanism 6 and a longitudinal plate roller adjustment mechanism 7 corresponding to the printing unit 2, and the transverse plate roller adjustment mechanism 6 and the longitudinal plate roller adjustment mechanism 7 are both electrically connected to the controller 5. If it is detected that the registration mark deviates in the transverse direction of the paper, it may be because the axial position between the plate roller 21, the rubber roller 22 or the impression roller 23 is inaccurate, which can be corrected by adjusting the axial adjustment devices at both ends of the roller. These adjustment devices are usually some screw mechanisms with scales. By rotating the screw and other devices, the roller is slightly displaced in the axial direction. When the registration mark deviates in the longitudinal direction of the paper, its circumferential position needs to be adjusted. This can be achieved by adjusting the gears or other connecting mechanisms of the plate roller 21 to achieve a slight displacement of the plate roller 21 in the circumferential direction. The above is the prior art, and people in this field should know it and will not go into details here. When the photoelectric scanner 4 detects a registration error, the corresponding transverse plate roller adjustment mechanism 6 and longitudinal plate roller adjustment mechanism 7 are controlled by the controller 5 to make adjustments to ensure accurate registration.

[0028] Preferably, the photoelectric scanner 4 is installed inside the chassis 1 through a three-dimensional pan-tilt platform 8. The three-dimensional pan-tilt platform 8 allows the photoelectric scanner 4 to rotate and move freely in three-dimensional space, so that the registration mark can be detected from different angles and positions, improving the comprehensiveness and accuracy of the detection, and to a certain extent buffering and offsetting slight vibrations from the outside, so that the photoelectric scanner 4 installed on the three-dimensional pan-tilt platform 8 maintains a relatively stable posture, thereby reducing problems such as image blurring caused by vibration and achieving an anti-shake effect.

[0029] Preferably, a coding mechanism 9 electrically connected to the controller 5 is also installed on the inner wall of the chassis 1. The coding mechanism 9 is installed at the downstream end of each printing unit 2 and is used to perform coding marking when the registration is inaccurate so that defective printed products with inaccurate registration can be subsequently removed.

[0030] Preferably, when the multiple circular frames 31 are concentric, the multiple straight portions 32 are offset from each other, so that the straight portions 32 will not overlap when multiple registration marks are registered, so that it is easy to observe which specific registration mark 3 produces the registration deviation.

[0031] The above description is merely an embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of the claims of the present invention.

Claims

1. A printing mark registration device for printed matter detection, comprising a plurality of printing units (2) installed inside a chassis (1), each of the printing units (2) corresponding to the printing of a color layer, the plurality of printing units (2) being arranged in sequence inside the chassis (1) for printing different color layers on paper in sequence, the printing units (2) comprising a plate cylinder (21), a rubber cylinder (22) and an impression cylinder (23), and a printing plate body (24) being provided on the plate cylinder (21), characterized in that: Also includes; A registration mark unit, which is composed of a registration mark member (3) arranged on each of the printing plate main bodies (24), each of the registration mark members (3) including a circular frame (31) and a straight portion (32) connected to the outside of the circular frame (31), and the diameters of the circular frames (31) of the registration mark members (3) sequentially arranged inside the chassis (1) gradually increase or decrease, and when two adjacent circular frames (31) are concentric, one end of the straight portion (32) connected on the inner circular frame (31) is aligned with the edge of the outer circular frame (31), indicating printing registration; A photoelectric scanner (4) is provided at the downstream end of each printing unit (2) and is used to collect images of overprint marks on paper after printing by adjacent printing units (2).

2. A printed mark registration device for printed matter detection according to claim 1, characterized in that: When the plurality of circular frames (31) are concentric, the plurality of straight line portions (32) are offset from each other.

3. The printing mark registration device for printed matter detection according to claim 1, characterized in that: The machine also includes a controller (5). The chassis (1) is provided with an alarm (51) corresponding to each printing unit (2). When the controller (5) receives information that the photoelectric scanner (4) detects a registration error, it controls the alarm (51) to issue an alarm.

4. A printing mark registration device for printed matter detection according to claim 3, characterized in that: The chassis (1) is provided with a transverse plate roller adjustment mechanism (6) and a longitudinal plate roller adjustment mechanism (7) corresponding to each printing unit (2), and the transverse plate roller adjustment mechanism (6) and the longitudinal plate roller adjustment mechanism (7) are both electrically connected to the controller (5).

5. The printing mark registration device for printed matter detection according to claim 1, characterized in that: The photoelectric scanner (4) is installed inside the chassis (1) via a three-dimensional platform (8).

6. The printing mark registration device for printed matter detection according to claim 3, characterized in that: A coding mechanism (9) electrically connected to the controller (5) is also installed on the inner wall of the chassis (1). The coding mechanism (9) is installed at the downstream end of each printing unit (2) and is used to perform coding marking when registration is inaccurate.

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