An ink supply control system, method and inkjet printing device suitable for use with a printhead module

Abstract

The application provides an ink supply control system suitable for a nozzle module, which comprises an upper computer, a main control board and a plurality of interface boards; the upper computer is connected with the main control board, and the main control board is connected with a plurality of interface boards distributed on an ink supply circuit through different interfaces of a field bus; wherein the plurality of interface boards are connected with each other to transmit printing instruction parameters of the interface boards, and the main control board performs correlation verification on the printing instruction parameters transmitted by different interface boards. By replacing the PLC control part of the existing ink supply control system, the application solves the problem of excessive wiring of the nozzle module controlled by the PLC, and the control board card is configured in a one master and multiple slave mode, and the data transmission between the plurality of interface boards is fed back to the main control board to realize the verification function of the interface board data, which is highly accurate, improves the reliability of the system and reduces the repair cost of the inkjet printing substrate.

Description

Technical Field

[0001] This invention relates to the field of inkjet printing technology, and in particular to an ink supply control system, method and inkjet printing apparatus suitable for printhead modules. Background Technology

[0002] As new display devices develop towards larger sizes, ultra-high definition, and flexibility, a major challenge they face is how to achieve high-precision manufacturing across scales—from nanoscale features to micrometer structures to meter-level devices—on large-area flexible substrates. With increasingly larger substrate sizes, the printing equipment used to manufacture these substrates needs to be correspondingly larger, while simultaneously maintaining high printing efficiency. Ideally, the goal would be to ultimately achieve a "One Pass" process, completing the task in a single print pass.

[0003] Because printheads are standardized in size, to achieve high-efficiency printing, major display manufacturers worldwide currently employ a printhead splicing solution. This involves combining multiple printheads on a single printing machine according to actual needs, and achieving high-efficiency printing through precise control of these printheads. Each printhead module has its own ink supply control system, which mainly uses components such as solenoid valves, proportional valves, level sensors, and leakage sensors. All of these components require connecting cables from ports to the controller.

[0004] It is evident that the ink supply control system has a large number of internal interfaces, and the wiring between these interfaces is complex, which easily leads to a high error rate. However, existing ink supply control systems cannot identify whether there are problems with the command parameters of each interface before the inkjet printing command is executed; if errors exist in the printing parameters and cannot be detected or corrected in a timely manner, it will cause considerable damage to the inkjet printing device. Summary of the Invention

[0005] Based on the problems existing in the prior art, the present invention aims to provide an ink supply control system and method suitable for printhead modules, so as to solve the problem of the inability to verify instruction data errors between the main control board and the interface board.

[0006] This invention provides an ink supply control system suitable for printhead modules, the system comprising: a host computer, a main control board, and multiple interface boards;

[0007] The host computer is connected to the main control board, and the main control board is connected to multiple interface boards distributed on the ink supply circuit through different interfaces of the fieldbus;

[0008] The interface boards are interconnected to transmit printing command parameters, and the main control board performs correlation verification through the printing command parameters sent by different interface boards.

[0009] In one embodiment of the present invention, the ink supply circuit includes a primary circulating ink path and a secondary circulating ink path, and multiple interface boards distributed in the primary circulating ink path or the secondary circulating ink path are interconnected.

[0010] In one embodiment of the present invention, the interface board is connected to at least one other interface board, and the interface board receives printing instruction parameters from the other interface boards and sends them to the main control board.

[0011] In one embodiment of the present invention, the interface board is connected only to another interface board, and the interconnected interface boards receive the printing instruction parameters of the other interface board and send them to the main control board.

[0012] In one embodiment of the present invention, multiple interface boards are connected sequentially in a cyclic manner, and each interface board receives the printing instruction parameters of the previous interface board and sends them to the main control board.

[0013] In one embodiment of the present invention, the interface board is connected to at least one of the solenoid valve, liquid level sensor, leakage sensor, proportional valve and flow monitor of the ink supply circuit via an IO interface.

[0014] In one embodiment of the present invention, the interface board adopts a DAC chip, and the DAC chip includes multiple voltage circuit acquisition channels, a drive compensation capacitor, and a filter capacitor;

[0015] Alternatively, the interface board may employ an ADC chip, which includes multiple voltage circuit acquisition channels, current circuit acquisition channels, and filter capacitors.

[0016] In one embodiment of the present invention, the printing instruction parameters include the DO data of the solenoid valve or the DAC data of the proportional valve.

[0017] The present invention provides an inkjet printing device, the inkjet printing device including a printhead module and an ink supply control system suitable for the printhead module as described in any of the above embodiments.

[0018] The present invention also provides an ink supply control method suitable for printhead modules, wherein the operation is performed using any of the ink supply control systems suitable for printhead modules described in the above embodiments, the method comprising:

[0019] Multiple interface boards are interconnected to transmit printing command parameters;

[0020] The main control board receives printing command parameters from multiple interface boards and compares the printing command parameters transmitted by the multiple interface boards.

[0021] Verify whether the parameters of multiple print commands on the same interface board are inconsistent. If there is an inconsistency, send an alarm message and prompt for correction.

[0022] Beneficial effects:

[0023] This invention provides an ink supply control system suitable for printhead modules. The ink supply control system includes: a host computer, a main control board, and multiple interface boards. The host computer is connected to the main control board, and the main control board is connected to the multiple interface boards distributed on the ink supply circuit through different interfaces of a fieldbus. The multiple interface boards are interconnected for transmitting printing command parameters. The main control board performs correlation verification based on the printing command parameters sent by different interface boards. This invention solves the problem of excessive wiring when using PLC to control printhead modules by replacing the PLC control part of existing ink supply control systems. Furthermore, the control board adopts a master-slave configuration, and the data transmission between multiple interface boards is sent back to the main control board to realize the interface board data verification function with high accuracy, improving system reliability and reducing the repair cost of inkjet printing substrates. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments or prior art, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the ink supply circuit device for the printhead module provided in an embodiment of the present invention;

[0026] Figure 2 This is a block diagram of an ink supply control system provided in an embodiment of the present invention;

[0027] Figure 3 This is a block diagram of an ink supply control system provided in an embodiment of the present invention;

[0028] Figure 4 This is a block diagram of an ink supply control system provided in an embodiment of the present invention;

[0029] Figure 5 This is a block diagram of the interface board controlling the ink supply device of the ink supply system provided in an embodiment of the present invention;

[0030] Figure 6 This is a diagram of the DAC chip on the interface board of the ink supply control system provided in an embodiment of the present invention;

[0031] Figure 7 This is a diagram of the ADC chip on the interface board of the ink supply control system provided in an embodiment of the present invention. Detailed Implementation

[0032] The following description of the embodiments is with reference to the accompanying illustrations, which illustrate specific embodiments in which the invention can be implemented. In the figures, structurally similar units are denoted by the same reference numerals.

[0033] like Figure 1 As shown, the ink supply circuit device for the printhead module involved in this invention includes a proportional valve, a primary ink supply circuit, a secondary ink supply circuit, and components for connecting to the printhead module, as well as multiple level sensors (101-118), solenoid valves (301-329), etc. The ink supply control system receives signal inputs from the level sensors and other devices, and outputs control signals to control the opening and closing of the solenoid valves in the ink supply circuit, supplying the ink required by the printhead of the printhead module.

[0034] It should be noted that, taking the operation of the ink supply circuit for starting printhead #1 as an example, the specific execution process is as follows: First, ink is injected from the main ink bottle into the secondary ink cartridge 1. At this time, solenoid valves 310, 315, and 318 need to be closed to prevent ink from flowing out from other channels. The channel to the positive pressure proportional valve 1 is opened, solenoid valve 307 is opened, and the parameters of the positive pressure proportional valve 1 are adjusted to obtain positive pressure from the main ink bottle. After the ink is pressed from the main ink bottle into the secondary ink cartridge 1, the position of the ink in the secondary ink cartridge 1 is monitored in real time by level sensors 107, 108, and 109. Once the ink reaches the required position, solenoid valve 313 is closed. The channel of the positive pressure proportional valve 3 is opened, and solenoid valves 309 and 317 are opened. The parameters of the positive pressure proportional valve 3 are adjusted so that the secondary ink cartridge uses positive pressure to press ink from the secondary ink cartridge 1 into printhead #1 through the pipe where solenoid valve 317 is located. In this way, ink is pressed from the main ink bottle into printhead #1 through the ink supply circuit. Once the printhead receives a sufficient amount of ink, the command is executed to shut it down.

[0035] In the ink supply circuit device of the above printhead module, the information collected by the interface boards of the ink supply control system in a distributed layout is finally aggregated on the main control board of the ink supply control system. All control lines involving the printhead module can be wired inside the printhead module.

[0036] This invention provides an ink supply control system suitable for printhead modules. The ink supply control system includes: a host computer, a main control board, and multiple interface boards.

[0037] The host computer is connected to the main control board, and the main control board is connected to multiple interface boards distributed on the ink supply circuit through different interfaces of the fieldbus;

[0038] It should be noted that both piezoelectric and electro-hydraulic printhead modules are applicable. Firstly, the ink supply control system of this invention replaces the PLC control section of the original control system, adopting a master-slave configuration to meet the AI, AO, DI, and DO interface requirements of multiple ink paths located in different positions. Currently, inkjet printers use an 8-channel ink supply control system, with the fewest having only one ink path. Therefore, the ink supply control system uses a single main control board with multiple interface boards, allowing for flexible selection of the number of interface boards based on actual needs. Since the required number of interfaces varies for the components in each ink path, the required number of interface boards may also differ between different ink paths. This allows for flexible configuration of the number of interface boards for each ink path, solving the problem of excessive wiring and high costs associated with PLC-controlled printhead modules, and achieving complete autonomy and control over the ink supply system control section. With this setup, the wiring for both the primary and secondary circulating ink paths is completed within the corresponding modules. Finally, the information is aggregated to the main control board of the ink supply system via a twisted-pair CAN bus (CAN_H, CAN_L), greatly reducing the workload of internal wiring.

[0039] It is worth mentioning that the multiple interface boards of the ink supply control system are interconnected to transmit the printing command parameters of the interface boards. The main control board performs correlation verification through the printing command parameters sent by different interface boards. This setup ensures high accuracy, improves system reliability, and reduces the repair cost of the inkjet printing substrate.

[0040] Due to the unique nature of inkjet printing, it has a low tolerance for errors. Once the parameters are set and the printing command is executed, the patterned or film structure on the printed substrate is difficult to modify or adjust later. Errors in parameters during printing can lead to losses of materials and production time. The final printing command parameters are executed through the interface board of the ink supply control system. To ensure correct command issuance and execution, a verification function for printing command parameters is implemented between boards within each ink path. Specifically, multiple interface boards are interconnected, and printing command parameters are transmitted between them. After receiving the printing command parameters, the interface board sends them to the main control board via a fieldbus. The main control board can receive printing command parameters from different interface boards. This allows for comparison and verification of multiple associated printing command parameters from a single interface board within the main control board, ensuring there are no deviations. This avoids the situation where, with only a single communication connection between the main control board and the interface board, errors in the interface board's printing command parameters would not be detected by the ink supply control system before inkjet printing begins. This setup reduces the probability of errors in inkjet printing and improves the reliability of the ink supply control system.

[0041] like Figure 2The diagram shown illustrates the ink supply control system block diagram, taking the interface board connection of a single-channel printhead module as an example. Interface board 1 and interface board 2 are interconnected, and interface board 3 and interface board 4 are interconnected. All of these interface boards are connected to the main control board of the ink supply control system via a CAN bus. During actual operation, before executing the command received from the main control board, interface board 1 simultaneously sends feedback data to both the main control board and interface board 2. Interface board 2, used to monitor interface board 1, processes the data and sends it back to the main control board. The main control board compares the two sets of data. If the two sets of data are completely consistent, the main control board issues a formal execution command to interface board 1, achieving online monitoring and verification of the printing command parameters. Similarly, the command verification process for interface board 2 is the same as that for interface board 1 and will not be described in detail here.

[0042] like Figure 3 The block diagram of the ink supply control system shown illustrates that the interface boards of the ink supply control system can be connected via RS232 communication lines. Interface board 1 is connected to interface board 2, interface board 2 is connected to interface board 3, interface board 3 is connected to interface board 4, and interface board 4 is connected to interface board 1 in turn. These multiple interface boards are connected sequentially in a loop. Interface board 2 receives the printing command parameters fed back from interface board 1, interface board 3 receives the printing command parameters fed back from interface board 2, interface board 4 receives the printing command parameters fed back from interface board 3, and finally interface board 1 receives the printing command parameters fed back from interface board 4. The above interface boards achieve a closed-loop monitoring connection to avoid data loss and errors. After receiving data from the previous interface board, the data is sent back to the main control board of the ink supply control system. The main control board compares the two sets of data received from the same interface board. If the two sets of data are completely consistent, the main control board of the ink supply control system issues a formal execution command, forming a complete closed-loop control.

[0043] like Figure 4 The diagram shows a block diagram of the ink supply control system. One interface board in the control system is connected to any other interface board. Specifically, interface board 1 is connected to interface boards 2, 3, and 4. Interface board 1 sends data to interface boards 2, 3, and 4. Interface boards 2, 3, and 4, which monitor interface board 1, process the data and send it back to the main control board of the ink supply system. The main control board performs multiple comparisons of the received data sets to further determine whether the consistency of the data sets meets the requirements, preventing misjudgments caused by individual data anomalies. This setup improves the accuracy of system verification. Interface boards 2, 3, and 4 are connected based on the same setup, and their instruction verification process is the same as that of interface board 1, and will not be described in detail here.

[0044] like Figure 5As shown, the ink supply system interface board used in this invention differs from the PLC-controlled relay-driven solenoid valve method. The interface board is designed with a maximum drive current of 2A, which is much higher than the drive current requirement of the solenoid valve, allowing it to directly drive the solenoid valve. The host computer communicates with the main control board of the ink supply system, thereby realizing real-time monitoring and acquisition of ink path information.

[0045] The ink supply system interface board's DO interface directly drives the solenoid valve. By controlling the on / off state of the solenoid valve, the ink supply circuit is controlled. Specifically, the host computer sends a control command to the solenoid valve via the main control board, which is ultimately executed by the ink supply system interface board. The level sensor and / or leakage sensor uploads their status data to the DI interface of the ink supply system interface board via PNP or NPN digital signal output. The interface board collects the information and sends it to the main control board, ultimately displaying it on the host computer's monitoring page. The proportional valve is controlled by setting a voltage. Specifically, the required pressure for the corresponding ink path during printing is calculated and converted into the corresponding control voltage value for the proportional valve. The host computer sets the voltage control value for the proportional valve, and the AO interface of the interface board transmits the voltage data set by the host computer to the proportional valve, thereby controlling the proportional valve and regulating the pressure. The proportional valve also has a feedback function, sending the internally received voltage value to the interface board via the UAI interface, and then to the main control board. The value is then displayed on the host computer's monitoring screen for comparison with the set value for verification. The flow monitor converts flow data into current internally and uploads it via the interface board's IAI interface. After the interface board collects the current, it sends it to the main control board, where the internal program converts the current value into the corresponding flow rate.

[0046] like Figure 6 As shown in the diagram, the DAC chip of the ink supply control system interface board provided in this embodiment is used in the ink supply system interface board. The DAC chip outputs 8 single-ended signals DACOUT1-DACOUT8. In order to adapt to the controlled proportional valve, the output voltage range is (0-10)V. C1, C2, C10, C15, C16, C17, C18, and C22 of the DAC chip are directly connected to ground and used as drive compensation capacitors; C5, C6, C7, C8, C9, C19, C20, and C21 of the DAC chip are used as filter capacitors to filter out noise and ensure signal stability; the DAC chip communicates with the control chip MCU via SPI communication through pins 16 (SPI5_CS), 17 (SPI5_CLK), 18 (SPI5_MISO), and 19 (SPI5_MOSI).

[0047] Figure 7As shown, the ADC chip used in the interface board of the ink supply control system provided in this embodiment. ADC1-ADC8 of the ADC chip are single-ended input (0-10)V circuit acquisition channels; ADCI1-ADCI4 of the ADC chip are 4 (0-20)mA circuit acquisition channels.

[0048] C3, C4, C11, C12, C13, and C14 of the ADC chip are used as filter capacitors to filter out noise and ensure signal stability.

[0049] The device communicates with the MCU control chip via pins 14 (SPI2_MISO), 15 (SPI2_MOSI), 16 (SPI2_CLK), and 17 (SPI2_CS).

[0050] The present invention also provides an ink supply control method suitable for printhead modules, which performs operations using the ink supply control system of the above embodiments, the method comprising:

[0051] Multiple interface boards are interconnected to transmit print command parameters; for specific connection methods of multiple interface boards, please refer to [reference needed]. Figures 2-4 The interface board connection structure of the ink supply control system; based on different interface board connection structures, different printing command parameter transmission modes between interface boards are realized.

[0052] The main control board receives printing command parameters from multiple interface boards and compares the printing command parameters transmitted by the multiple interface boards. The main control board compares two or more sets of data received from the same interface board to see if the two or more sets of data are completely consistent, that is, to verify whether the multiple printing command parameters of the same interface board are deviated. If they are completely consistent, the ink supply control system main control board issues the formal execution command. If there is a deviation, the main control board or the host computer sends an alarm message and prompts for correction to ensure that the printhead module prints without errors and improve the reliability of the system.

[0053] The present invention also provides an inkjet printing apparatus, which includes a printhead module and an ink supply control system adapted to the printhead module in the above embodiments. The inkjet printing apparatus may include a printhead module with multiple printheads, each printhead distributing ink droplets onto the surface of a substrate. The inkjet printing printhead module is connected to an ink supply circuit, and the ink supply control system provided in the above embodiments is used to supply ink droplet material. Combined with the ink droplet distribution of the printhead module, the inkjet printing manufacturing process of the substrate is realized.

[0054] It should be noted that although the present invention has been disclosed above with specific embodiments, the above embodiments are not intended to limit the present invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope defined in the claims.

Claims

1. An ink supply control system suitable for printhead modules, characterized in that, The system includes: a host computer, a main control board, and multiple interface boards; The host computer is connected to the main control board, and the main control board is connected to multiple interface boards distributed on the ink supply circuit through different interfaces of the fieldbus; The interface boards are interconnected to transmit printing command parameters, and the main control board performs correlation verification through the printing command parameters sent by different interface boards. The main control board receives printing command parameters from multiple interface boards and compares the printing command parameters transmitted by the multiple interface boards. Verify whether the parameters of multiple printing commands on the same interface board are deviated. If a deviation exists, send an alarm message and prompt for correction.

2. The ink supply control system for a printhead module according to claim 1, characterized in that, The ink supply circuit includes a primary circulating ink circuit and a secondary circulating ink circuit, and multiple interface boards distributed in the primary circulating ink circuit or the secondary circulating ink circuit are interconnected.

3. The ink supply control system for a printhead module according to claim 2, characterized in that, The interface board is connected to at least one other interface board, and the interface board receives printing instruction parameters from the other interface boards and sends them to the main control board.

4. The ink supply control system for a printhead module according to claim 3, characterized in that, The interface board is connected to only one other interface board. The interconnected interface boards receive the printing instruction parameters from the other interface board and send them to the main control board.

5. The ink supply control system for a printhead module according to claim 3, characterized in that, Multiple interface boards are connected sequentially in a loop. Each interface board receives the printing instruction parameters from the previous interface board and sends them to the main control board.

6. The ink supply control system for a printhead module according to claim 1, characterized in that, The interface board is connected to at least one of the solenoid valve, liquid level sensor, leakage sensor, proportional valve and flow monitor in the ink supply circuit via the IO interface.

7. The ink supply control system for a printhead module according to claim 1, characterized in that, The interface board uses a DAC chip, which includes multiple voltage circuit acquisition channels, drive compensation capacitors, and filter capacitors. Alternatively, the interface board may employ an ADC chip, which includes multiple voltage circuit acquisition channels, current circuit acquisition channels, and filter capacitors.

8. The ink supply control system for a printhead module according to claim 6, characterized in that, The printing instruction parameters include the DO data of the solenoid valve or the DAC data of the proportional valve.

9. An inkjet printing device, characterized in that, The inkjet printing apparatus includes a printhead module and an ink supply control system for the printhead module as described in any one of claims 1-8.

10. A method for controlling ink supply to a printhead module, characterized in that, The method of performing operation using the ink supply control system according to any one of claims 1-8 includes: Multiple interface boards are interconnected to transmit printing command parameters; The main control board receives printing command parameters from multiple interface boards and compares the printing command parameters transmitted by the multiple interface boards. Verify whether the parameters of multiple print commands on the same interface board are inconsistent. If there is an inconsistency, send an alarm message and prompt for correction.

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