An on-line digital printing device with visual inspection

Abstract

The utility model discloses a kind of online digital printing devices with visual inspection, belong to ink-jet printing field, including digital printing module and visual inspection module, the digital printing module and visual inspection module are all installed on mounting bracket, multiple groups of transmission rollers are equipped on the mounting bracket, digital printing module includes color mark sensor, encoder, printing module and curing lamp, encoder is installed on one transmission roller, encoder side is equipped with color mark sensor;Control module is equipped in the inside of digital printing module, and the printing module in digital printing module includes print head, ink supply module, curing lamp is installed on mounting bracket, and visual inspection module includes light source and camera.The utility model real-time quality monitoring, greatly reduce material waste and subsequent sorting cost, high-precision printing and detection are synchronous, greatly improve the reliability and precision of system, significantly improve the automation degree and overall efficiency of production line.

Description

Technical Field

[0001] This utility model relates to the field of inkjet printing, specifically an online digital printing device with visual inspection. Background Technology

[0002] In the production and processing of continuous materials such as modern packaging, labels, and films, it is often necessary to print variable information such as dates, batch numbers, QR codes, serial numbers, and personalized patterns on the product surface. Digital printing technology is becoming increasingly popular in such applications due to its advantages, such as no need for plate making, flexibility, and suitability for short-run jobs. Traditional online digital printing systems typically include an unwinding device, a tension control system, guide rollers, a digital printing module, a drying device, and a rewinding device. The substrate moves continuously under the traction of the transfer rollers. When it passes through the digital printing module, the print head sprays ink onto specific locations on the material according to the instructions of the control system. Subsequently, the ink is quickly dried and fixed by the curing device, and finally, the material is rewound or proceeds to the next process.

[0003] However, existing online digital printing systems have the following significant shortcomings: 1. Lack of real-time quality monitoring: The printing process may lead to printing defects such as missing codes, blurriness, skewing, and color deviation due to factors such as printhead clogging, insufficient ink, material surface contamination, or transmission jitter. Traditional methods often rely on manual sampling or offline inspection in subsequent processes, which cannot detect defects in real time, resulting in a large number of defective products, causing material waste and rework costs. 2. Printing positioning accuracy needs improvement: Although many systems use encoders for speed synchronization and color mark sensors for coarse positioning, for high-precision printing requirements such as inkjet printing within specific frames of pre-printed patterns, the dynamic response accuracy and anti-interference capabilities of existing systems are sometimes insufficient to guarantee absolute accuracy for every print. Utility Model Content

[0004] To address some existing problems, the purpose of this invention is to provide an online digital printing device with visual inspection, so as to solve the problems of lack of real-time quality monitoring and the need to improve printing positioning accuracy in existing online digital printing systems.

[0005] To achieve the above objectives, this utility model provides the following technical solution: An online digital printing device with visual inspection includes a digital printing module and a visual inspection module, both of which are mounted on a mounting bracket. The mounting bracket has multiple sets of transfer rollers. The digital printing module includes a color mark sensor, an encoder, a printing module, and a curing lamp. An encoder is mounted on one of the transfer rollers, and a color mark sensor is located on one side of the encoder. The digital printing module contains a control module. The printing module within the digital printing module includes a printhead and an ink supply module. The curing lamp is mounted on the mounting bracket. The visual inspection module includes a light source and a camera.

[0006] As a further embodiment of this utility model: the color mark sensor and the input end of the control module are communicatively connected; the encoder and the input end of the control module are communicatively connected; and the print head, the ink supply module and the output end of the control module are communicatively connected.

[0007] As a further embodiment of this invention, the trigger end of the camera and the color mark sensor are connected in communication.

[0008] As a further embodiment of this invention: the camera is installed downstream of the curing lamp.

[0009] As a further embodiment of this invention, the curing lamp is a UV LED curing lamp or an infrared drying device.

[0010] As a further embodiment of this utility model, the light source is one of a ring LED light source, a strip light source, or a coaxial light source.

[0011] As a further embodiment of this invention, the camera is a CCD camera or a CMOS camera.

[0012] As a further embodiment of this utility model: the printhead is a piezoelectric inkjet printhead, and the ink supply module includes an ink tank, a pump, a filter, and an ink delivery pipeline.

[0013] As a further embodiment of this invention: the ink tank is connected to the input end of the filter via an ink supply pipeline, and the output end of the filter is connected to the printhead.

[0014] As a further embodiment of this utility model, a pump is installed on the ink supply pipeline.

[0015] Compared with the prior art, the beneficial effects of this utility model are: This invention enables precise printing of the required materials. Color mark sensors and encoders ensure printing accuracy and quality, while curing lamps provide timely drying. Real-time quality monitoring is maintained during printing to prevent batch defects. The vision inspection module works synchronously with the printing module, taking real-time photos of each printed item for inspection. This allows for the immediate detection of printing defects such as content errors, blurriness, missing parts, and positional deviations during production. It can also be connected to a subsequent rejection device to promptly remove defective products, significantly reducing material waste and subsequent sorting costs. High integration saves space and cost, and efficient signal coordination significantly improves the automation level and overall efficiency of the production line. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of an online digital printing device with visual inspection capabilities.

[0017] In the diagram: 1. Mounting bracket; 2. Color mark sensor; 3. Encoder; 4. Printhead; 5. Ink supply module; 6. Control module; 7. Digital printing module; 8. Vision inspection module; 9. Camera; 10. Light source; 11. Curing lamp. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0019] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," and "linked" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0020] The purpose of this invention is to add a coding function to the equipment while incorporating a real-time monitoring function, enabling monitoring of the printing effect during printing and ensuring printing quality. This invention provides an integrated device that deeply integrates high-precision online digital printing with real-time visual inspection, achieving self-monitoring and quality assurance of the printing process.

[0021] Please see Figure 1 An online digital printing device with visual inspection includes a digital printing module 7 and a visual inspection module 8. Both the digital printing module 7 and the visual inspection module 8 are mounted on a mounting bracket 1. The mounting bracket 1 ensures the stability of the device and facilitates its operation. A robust mounting bracket 1 provides a mounting foundation for all functional components and ensures the stability of their relative positions.

[0022] The mounting bracket 1 is equipped with multiple sets of transmission rollers. The printed materials, such as packaging film, label paper, and fabric, move continuously in the direction of the arrow in the figure under the action of an external traction device, and bypass the multiple transmission rollers on the mounting bracket 1.

[0023] The digital printing module 7 includes a color mark sensor 2, an encoder 3, a printing module, and a curing lamp 11. The encoder 3 is installed on a transfer roller. The encoder is installed on a specific transfer roller. When the material is running, it drives the transfer roller to rotate, and the encoder starts to work, transmitting the equipment operation signal and running speed to the printing module to control the operation of the printing module and the printing speed. A color mark sensor 2 is provided on one side of the encoder 3; a control module 6 is provided inside the digital printing module 7, and the input end of the color mark sensor 2 and the control module 6 are communicatively connected; the color mark sensor faces the surface of the product to be printed, tracks a specific positioning mark, and transmits a signal to the digital printing module to control the start time of the printing module, ensuring that the printed content is in the designated position on the product; at the same time, the color mark sensor will also transmit a signal to the vision inspection system to trigger the inspection work; The printing module within the digital printing module 7 includes a printhead 4, an ink supply module 5, and a control module 6 whose outputs are communicatively connected. Upon receiving signals from the encoder and color mark sensor, the control module 6 controls the printhead to spray ink onto designated locations on the printed material. The control module 6, such as an industrial computer or PLC, receives signals from the encoder 3 and color mark sensor 2. Based on the speed signal from the encoder 3, the control module 6 controls the inkjet frequency of the printhead 4 to achieve speed synchronization, and accurately calculates the delay based on the signal from the color mark sensor 2, controlling the printhead 4 to start printing at the precise moment to ensure the information is printed at the designated location.

[0024] Printhead 4 is a piezoelectric inkjet printhead, and ink supply module 5 includes an ink tank, pump, filter and ink supply line, which facilitates control of ink supply and printing.

[0025] The ink tank is connected to the input end of the filter via an ink supply line, and the output end of the filter is connected to the print head 4. A pump is installed on the ink supply line, which drives the ink in the ink tank to be transported through the ink supply line to the filter for filtration before printing. This facilitates digital printing, ensures safety, and makes the device easy to use. Simultaneously, the filter prevents impurities in the ink from affecting the printing process, improving print quality and effect.

[0026] Curing lamp 11 is installed on mounting bracket 1 and arranged behind the printing position. Curing lamp 11 is a UV LED curing lamp or an infrared drying device. After the ink falls onto the surface of the material to be printed, it passes through the curing lamp to dry the ink and complete the printing work. After printing, the material immediately passes under the curing lamp 11, such as a UV LED lamp or a hot air device, and the ink is instantly dried and cured.

[0027] The visual inspection module 8 includes a light source 10 and a camera 9. The trigger terminal of the camera 9 is communicatively connected to the color mark sensor 2. The camera 9 is installed downstream of the curing lamp 11. The light source 10 is one of a ring LED light source, a strip light source, or a coaxial light source. The light source 10 provides illumination to ensure the color effect of the image captured by the camera 9. The camera 9 is a CCD camera or a CMOS camera. After receiving the signal from the color mark sensor, the camera 9 takes pictures at specific time points and displays the images on the display, completing the real-time monitoring. The same trigger signal generated by the color mark sensor 2 is sent to the visual inspection module 8, or first to the control module 6 and then forwarded, while simultaneously being sent to the control module 6 to trigger printing. The control system calculates a precise time delay based on the distance the material travels from below the print head 4 to below the camera 9. When the delay time is reached, the camera 9 is triggered to capture the image of the newly printed and cured pattern. The captured image is transmitted to the image processing system, which can be integrated into the control module 6 or set up independently for real-time analysis to determine whether the printed content is complete, clear, and correctly positioned.

[0028] This invention combines digital printing and visual inspection functions, enabling signal synchronization between existing equipment and online digital printing and visual inspection modules. It can monitor printing quality and control the number of defective products while printing. By integrating the printing module and visual inspection module into a unified bracket and sharing the trigger signal of the color mark sensor, it achieves precise synchronization between printing and inspection, and can complete quality inspection immediately while printing, effectively controlling the defective product rate.

[0029] This invention provides real-time quality monitoring to eliminate batch defects. The visual inspection module works synchronously with the printing module, taking photos of each printed product in real time. It can detect printing defects such as content errors, blurriness, missing parts, and positional deviations in the production process at the first moment. It can also be connected to the subsequent rejection device to remove unqualified products in a timely manner, which greatly reduces material waste and subsequent sorting costs.

[0030] This invention enables high-precision printing and inspection synchronization. It utilizes the same color mark sensor signal to simultaneously trigger printing and inspection actions, ensuring a high degree of consistency between the inspection target and the printing target. This avoids misjudgment or missed detection caused by asynchronous signal sources, greatly improving the reliability and accuracy of the system.

[0031] This utility model is highly integrated, saving space and cost. It integrates printing and testing functions into a robust mounting bracket, with a compact structure that reduces the footprint of independent equipment and the complex docking and debugging work, thereby reducing the total cost of ownership and installation complexity.

[0032] This invention improves production efficiency and automation, realizing an online integrated process of "printing-curing-testing". Quality inspection can be completed without interrupting production, significantly improving the automation level and overall efficiency of the production line.

[0033] This invention features highly efficient signal coordination. The encoder provides a global speed reference, the color mark sensor provides a precise position reference, and the control module uniformly schedules printing and inspection actions, making the entire system operate in a coordinated and rapid manner.

[0034] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects; the scope of this invention is defined by the appended claims rather than the foregoing description; and thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0035] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution; this narrative style is merely for clarity; those skilled in the art should consider the specification as a whole; the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An online digital printing apparatus with visual inspection, characterized in that, The digital printing module (7) and the visual inspection module (8) are both mounted on a mounting bracket (1). The mounting bracket (1) is provided with multiple sets of transmission rollers. The digital printing module (7) includes a color mark sensor (2), an encoder (3), a printing module, and a curing lamp (11). An encoder (3) is mounted on one of the transmission rollers, and a color mark sensor (2) is provided on one side of the encoder (3). The printing module in the digital printing module (7) includes a print head (4) and an ink supply module (5). The curing lamp (11) is mounted on the mounting bracket (1). The visual inspection module (8) includes a light source (10) and a camera (9).

2. The online digital printing apparatus with visual inspection according to claim 1, characterized in that, The digital printing module (7) is equipped with a control module (6), the color mark sensor (2) is connected to the input end of the control module (6), the encoder (3) is connected to the input end of the control module (6), and the print head (4), the ink supply module (5) is connected to the output end of the control module (6).

3. The online digital printing apparatus with visual inspection according to claim 2, characterized in that, The trigger end of the camera (9) is connected to the color mark sensor (2) in communication.

4. The online digital printing apparatus with visual inspection according to claim 3, characterized in that, The camera (9) is installed downstream of the curing lamp (11).

5. An online digital printing apparatus with visual inspection according to claim 4, characterized in that, The curing lamp (11) is a UV LED curing lamp or an infrared drying device.

6. The online digital printing apparatus with visual inspection according to claim 5, characterized in that, The light source (10) is one of a ring LED light source, a strip light source, or a coaxial light source.

7. An online digital printing apparatus with visual inspection according to claim 6, characterized in that, The camera (9) is a CCD camera or a CMOS camera.

8. An online digital printing apparatus with visual inspection according to claim 7, characterized in that, The printhead (4) is a piezoelectric inkjet printhead, and the ink supply module (5) includes an ink tank, a pump, a filter, and an ink supply pipeline.

9. An online digital printing apparatus with visual inspection according to claim 8, characterized in that, The ink tank is connected to the input end of the filter via an ink supply line, and the output end of the filter is connected to the printhead (4).

10. An online digital printing apparatus with visual inspection according to claim 9, characterized in that, A pump is installed on the ink supply pipeline.

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