Gas circuit control device and digital printer

Abstract

The invention relates to a gas circuit control device and a digital printer. The gas circuit control device comprises a main ink box, an auxiliary ink box, a positive pressure module, a negative pressure module, an auxiliary ink box switching valve and a main ink box positive and negative pressure switching valve. The first end of the auxiliary ink box switch valve is connected with the auxiliary ink box, the second end of the auxiliary ink box switch valve is connected with the negative pressure module, and the auxiliary ink box switch valve is used for opening or closing a passage between the auxiliary ink box and the negative pressure module; the first end of the main ink box positive and negative pressure switching valve is connected with the main ink box, the second end of the main ink box positive and negative pressure switching valve is connected with the positive pressure module, the third end of the main ink box positive and negative pressure switching valve is connected with the negative pressure module, and the main ink box positive and negative pressure switching valve is used for opening or closing a passage between the main ink box and the positive pressure module and / or the negative pressure module. By controlling the positive pressure and the negative pressure, different working states of the nozzle can be accurately switched, so that the material loss is reduced, and the production efficiency is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of digital printers, and in particular to an air path control device and a digital printer. Background Art

[0002] Based on the current characteristics of the nozzles, for cardboard printing, some basic printings with high requirements need to be stopped for maintenance after 2 to 3 hours of printing, otherwise the nozzles will break and the printing quality will decline. After a long period of exploration, nozzle manufacturers have launched circulating nozzle products. In the case of nozzle improvements, the control of its air path is extremely critical. Summary of the invention

[0003] The embodiments of the present application provide an air circuit control device and a digital printer, which can achieve accurate conversion of different working states of the nozzle by controlling positive and negative pressures, thereby reducing material loss and improving production efficiency.

[0004] In the first aspect, an embodiment of the present application provides an air circuit control device, which includes: a main ink cartridge, the main ink cartridge includes a first accommodating chamber; an auxiliary ink cartridge, the auxiliary ink cartridge includes a second accommodating chamber; a positive pressure module, the positive pressure module is used to generate positive pressure in the first accommodating chamber; a negative pressure module, the negative pressure module is used to generate negative pressure in the first accommodating chamber and / or the second accommodating chamber; an auxiliary ink cartridge switch valve, the first end of the auxiliary ink cartridge switch valve is connected to the auxiliary ink cartridge, the second end of the auxiliary ink cartridge switch valve is connected to the negative pressure module, and the auxiliary ink cartridge switch valve is used to open or close the passage between the auxiliary ink cartridge and the negative pressure module; a main ink cartridge positive and negative pressure switching valve, the first end of the main ink cartridge positive and negative pressure switching valve is connected to the main ink cartridge, the second end of the main ink cartridge positive and negative pressure switching valve is connected to the positive pressure module, the third end of the main ink cartridge positive and negative pressure switching valve is connected to the negative pressure module, and the main ink cartridge positive and negative pressure switching valve is used to open or close the passage between the main ink cartridge and the positive pressure module and / or the negative pressure module.

[0005] In some embodiments, the positive pressure module includes: a positive pressure tank, which is connected to the second end of the positive and negative pressure switching valve of the main ink cartridge; a first air pressure regulating module, which is connected to the positive pressure tank, and the first air pressure regulating module regulates the air pressure in the positive pressure tank to positive pressure.

[0006] In some embodiments, the first air pressure regulating module includes: a first vacuum pump, which is used to compress external gas into the positive pressure tank to make the air pressure in the positive pressure tank positive pressure, or to evacuate the positive pressure tank to reduce the positive pressure in the positive pressure tank; a low positive pressure valve, a first end of the low positive pressure valve is connected to the positive pressure tank, and a second end of the low positive pressure valve is connected to the first vacuum pump, and the low positive pressure valve is used to open or close the passage between the air outlet of the first vacuum pump and the positive pressure tank; a low negative pressure valve, a first end of the low negative pressure valve is connected to the positive pressure tank, and a second end of the low negative pressure valve is connected to the first vacuum pump, and the low negative pressure valve is used to open or close the passage between the air inlet of the first vacuum pump and the positive pressure tank; a positive pressure tank pressure relief valve, the positive pressure tank pressure relief valve is connected to the positive pressure tank, and the positive pressure tank pressure relief valve is used to reduce the positive pressure in the positive pressure tank.

[0007] In some embodiments, the negative pressure module includes: a negative pressure tank, which is respectively connected to the second end of the auxiliary ink cartridge switch valve and the third end of the main ink cartridge positive and negative pressure switch valve; a second air pressure regulating module, which is connected to the negative pressure tank, and the second air pressure regulating module regulates the air pressure in the negative pressure tank to negative pressure.

[0008] In some embodiments, the second air pressure regulating module includes: a second vacuum pump, which is used to evacuate the negative pressure tank to make the air pressure in the negative pressure tank negative pressure; a negative pressure tank switch valve, a first end of the negative pressure tank switch valve is connected to the negative pressure tank, and a second end of the negative pressure tank switch valve is connected to the second vacuum pump, and the negative pressure tank switch valve is used to open or close the passage between the second vacuum pump and the negative pressure tank; a negative pressure tank pressure relief valve, which is connected to the negative pressure tank and is used to reduce the negative pressure in the negative pressure tank.

[0009] In some embodiments, the air circuit control device further includes: a detection module, the detection module includes a first liquid level sensor, a second liquid level sensor, a first pressure sensor, and a second pressure sensor, the first liquid level sensor and the first pressure sensor are both arranged in the main ink cartridge, the second liquid level sensor and the second pressure sensor are both arranged in the auxiliary ink cartridge, the first liquid level sensor is used to measure a first liquid level value in the main ink cartridge, the second liquid level sensor is used to measure a second liquid level value in the auxiliary ink cartridge, the first pressure sensor is used to measure a first air pressure value in the main ink cartridge, and the second The pressure sensor is used to measure the second air pressure value in the auxiliary ink cartridge; the controller is respectively connected to the first liquid level sensor, the second liquid level sensor, the first pressure sensor, the second pressure sensor, the positive pressure module, the negative pressure module, the auxiliary ink cartridge switch valve, and the main ink cartridge positive and negative pressure switching valve, and the controller is used to control the positive pressure module, the negative pressure module, the auxiliary ink cartridge switch valve, and the main ink cartridge positive and negative pressure switching valve according to the first liquid level value, the second liquid level value, the first air pressure value, and the second air pressure value to adjust the air pressure of the main ink cartridge and the auxiliary ink cartridge.

[0010] In some embodiments, the air circuit control device also includes: an air source connection, which is used to filter the input gas; a pressure regulating valve, which is connected to the air source connection, and is used to regulate the air pressure of the input gas; an ink pressure switching valve, a first end of the ink pressure switching valve is connected to the main ink cartridge, a second end of the ink pressure switching valve is connected to the first end of the positive and negative pressure switching valve of the main ink cartridge, a third end of the ink pressure switching valve is connected to the pressure regulating valve, and the ink pressure switching valve is used to open or close the passage between the main ink cartridge and the positive and negative pressure switching valve of the main ink cartridge and / or the pressure regulating valve.

[0011] In some embodiments, the air circuit control device also includes: an ink pressure relief valve, a first end of the ink pressure relief valve is connected to the main ink cartridge, a second end of the ink pressure relief valve is connected to the ink pressure switching valve, and the ink pressure relief valve is used to reduce the positive pressure in the main ink cartridge.

[0012] In some embodiments, the number of the main ink cartridges is N, where N is a positive integer. When the number of the main ink cartridges is N, the number of the auxiliary ink cartridges, the positive pressure modules, the negative pressure modules, the auxiliary ink cartridge switch valves, the main ink cartridge positive and negative pressure switching valves, the ink pressure switching valves, and the ink pressure relief valves are all N, and the number of the air source connector and the pressure regulating valve is one; wherein, a secondary ink cartridge is connected to a negative pressure module through a secondary ink cartridge switch valve, and a main ink cartridge is connected to a positive pressure module in sequence through an ink pressure relief valve, an ink pressure switching valve, and a main ink cartridge positive and negative pressure switching valve, the main ink cartridge positive and negative pressure switching valve is also connected to the negative pressure module, and each of the ink pressure switching valves is also connected to the pressure regulating valve.

[0013] In a second aspect, an embodiment of the present application provides a digital printer, which includes: a nozzle, a circulation pump, an ink barrel, and an air path control device as described above; wherein the main ink cartridge is respectively connected to the nozzle, the circulation pump, and the ink barrel, and the auxiliary ink cartridge is respectively connected to the nozzle and the circulation pump.

[0014] Different from the prior art, the embodiment of the present application provides an air circuit control device and a digital printer, wherein the air circuit control device comprises: a main ink cartridge, wherein the main ink cartridge comprises a first accommodating chamber; an auxiliary ink cartridge, wherein the auxiliary ink cartridge comprises a second accommodating chamber; a positive pressure module, wherein the positive pressure module is used to generate positive pressure in the first accommodating chamber; a negative pressure module, wherein the negative pressure module is used to generate negative pressure in the first accommodating chamber and / or the second accommodating chamber; an auxiliary ink cartridge switch valve, wherein a first end of the auxiliary ink cartridge switch valve is connected to the auxiliary ink cartridge, a second end of the auxiliary ink cartridge switch valve is connected to the negative pressure module, and the auxiliary ink cartridge switch valve is used to open or close a passage between the auxiliary ink cartridge and the negative pressure module; a main ink cartridge positive and negative pressure switching valve, wherein a first end of the main ink cartridge positive and negative pressure switching valve is connected to the main ink cartridge, a second end of the main ink cartridge positive and negative pressure switching valve is connected to the positive pressure module, a third end of the main ink cartridge positive and negative pressure switching valve is connected to the negative pressure module, and the main ink cartridge positive and negative pressure switching valve is used to open or close a passage between the main ink cartridge and the positive pressure module and / or the negative pressure module. The design of the main ink cartridge positive and negative pressure switching valve and the auxiliary ink cartridge switch valve in the embodiment of the present application can flexibly adapt to different working scenarios. For example, under different printing tasks, the ink supply and system operation can be optimized, thereby improving the versatility and adaptability of the device. In addition, by controlling the positive and negative pressures, the different working states of the printhead can be accurately converted, thereby achieving the purpose of reducing material loss and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 is a schematic diagram of the structure of a digital printer provided by some embodiments of the present application;

[0017] Figure 2 is a schematic diagram of the structure of a gas path control device provided in some embodiments of the present application;

[0018] Figure 3 is a schematic diagram of the structure of a positive pressure module provided in some embodiments of the present application;

[0019] Figure 4 is a schematic structural diagram of a positive pressure module provided in some other embodiments of the present application;

[0020] Figure 5 is a schematic diagram of the structure of a negative pressure module provided in some embodiments of the present application;

[0021] Figure 6 is a schematic structural diagram of a negative pressure module provided in some other embodiments of the present application;

[0022] Figure 7 is a schematic diagram of the structure of the gas path control device provided in other embodiments of the present application;

[0023] Figure 8 is a schematic diagram of the structure of the gas path control device provided in other embodiments of the present application;

[0024] Fig. 9 It is a schematic diagram of the structure of the gas path control device provided in other embodiments of the present application. DETAILED DESCRIPTION

[0025] The principles and spirit of the present disclosure will be described below with reference to several exemplary embodiments shown in the accompanying drawings. It should be understood that the description of these specific embodiments is only to enable those skilled in the art to better understand and implement the present disclosure, and does not limit the scope of the present disclosure in any way. In the following description and claims, unless otherwise defined, all technical and scientific terms used herein have the meanings commonly understood by those of ordinary skill in the art. As used herein, the term "including" and similar terms should be understood as open inclusion, that is, "including but not limited to."

[0026] See also Figure 1 , Figure 1It is a schematic diagram of the structure of a digital printer 1000 provided in some embodiments of the present application.

[0027] The embodiment of the present application provides a digital printer 1000, which includes: a nozzle 300, a circulation pump 200, an ink barrel 400, and the following air circuit control device 100. The main ink cartridge 20 is connected to the nozzle 300, the circulation pump 200, and the ink barrel 400, respectively, and the auxiliary ink cartridge 10 is connected to the nozzle 300 and the circulation pump 200, respectively.

[0028] The circulation pump 200 is used to drive the ink to be transferred from the auxiliary ink cartridge 10 to the main ink cartridge 20. It provides power for the circulation of the ink to ensure that the ink can flow continuously and stably.

[0029] The nozzle 300 is a circulating nozzle. This means that the ink circulates inside the nozzle 300. This circulation design has many advantages, such as preventing the ink from drying up and clogging inside the nozzle and at the nozzle hole, ensuring the stable inkjet performance of the nozzle, and improving the printing quality and the service life of the nozzle. The nozzle 300 is used to eject the ink in the main ink cartridge 20 onto the printing medium to form images and transfer local ink to the auxiliary ink cartridge 10.

[0030] The ink barrel 400 is a container for storing ink. In the digital printer 1000, the main ink cartridge 20 is connected to the ink barrel 400, and the ink barrel 400 provides ink replenishment for the main ink cartridge 20. When the ink in the main ink cartridge 20 is consumed to a certain extent, the ink in the ink barrel 400 can be transported to the main ink cartridge 20 through corresponding pipes and control devices to ensure that the printing process can continue and avoid interruption of printing due to insufficient ink.

[0031] In this embodiment, the pressure difference between the main ink cartridge 20 and the auxiliary ink cartridge 10 controls the circulation of ink through the nozzle 300, and the ink is transferred from the main ink cartridge 20 to the auxiliary ink cartridge 10, so that the ink can carry away the bubbles generated during the printing process of the nozzle 300 or the sediment that partially blocks the nozzle 300. This prevents bubbles or sediments from being stored inside the nozzle 300, blocks the filter screen inside the nozzle 300, and causes the nozzle hole to be blocked, thereby finally achieving continuous printing. While the ink is transferred from the main ink cartridge 20 to the auxiliary ink cartridge 10 through the nozzle 300, the low-pulse circulation pump 200 transfers the ink from the auxiliary ink cartridge 10 to the main ink cartridge 20 again, thereby realizing closed-loop control of the ink path.

[0032] See also Figure 2 , Figure 2 It is a schematic diagram of the structure of the gas path control device 100 provided in some embodiments of the present application.

[0033] The embodiment of the present application provides an air circuit control device 100, which includes: an auxiliary ink cartridge 10, a main ink cartridge 20, an auxiliary ink cartridge switch valve 30, a main ink cartridge positive and negative pressure switch valve 40, a negative pressure module 50, and a positive pressure module 60.

[0034] Wherein, the main ink cartridge 20 includes a first accommodating chamber (not shown). The auxiliary ink cartridge 10 includes a second accommodating chamber (not shown). The positive pressure module 60 is used to generate positive pressure in the first accommodating chamber. The negative pressure module 50 is used to generate negative pressure in the first accommodating chamber and / or the second accommodating chamber. The first end of the auxiliary ink cartridge switch valve 30 is connected to the auxiliary ink cartridge 10, the second end of the auxiliary ink cartridge switch valve 30 is connected to the negative pressure module 50, and the auxiliary ink cartridge switch valve 30 is used to open or close the passage between the auxiliary ink cartridge 10 and the negative pressure module 50. The first end of the main ink cartridge positive and negative pressure switching valve 40 is connected to the main ink cartridge 20, the second end of the main ink cartridge positive and negative pressure switching valve 40 is connected to the positive pressure module 60, the third end of the main ink cartridge positive and negative pressure switching valve 40 is connected to the negative pressure module 50, and the main ink cartridge positive and negative pressure switching valve 40 is used to open or close the passage between the main ink cartridge 20 and the positive pressure module 60 and / or the negative pressure module 50. In certain embodiments of the present application, the main ink cartridge positive and negative pressure switching valve 40 is specifically a three-way valve. The use of a three-way valve can reduce electrical components and reduce the complexity of the control valve.

[0035] In the embodiment of the present application, when it is necessary to generate negative pressure in the second accommodating chamber of the auxiliary ink cartridge 10, first ensure that the auxiliary ink cartridge switch valve 30 is in the open state, and at this time, the negative pressure module 50 is connected to the passage of the auxiliary ink cartridge 10. The negative pressure module 50 starts to work, and extracts gas from the second accommodating chamber of the auxiliary ink cartridge 10 through a related air extraction mechanism (such as the principle of a vacuum pump, which may vary depending on the device), so that the air pressure inside the second accommodating chamber gradually decreases, thereby generating a negative pressure environment. In this process, the ink and other media in the auxiliary ink cartridge 10 will be affected by the negative pressure. For example, in the ink replenishment scenario, the ink in other storage containers (such as the main ink cartridge 20) will be more easily sucked into the auxiliary ink cartridge 10 under the action of the pressure difference.

[0036] If positive pressure is to be generated in the first accommodation chamber of the main ink cartridge 20, the passage between the first end and the second end of the positive and negative pressure switching valve 40 of the main ink cartridge needs to be opened, that is, the main ink cartridge 20 and the positive pressure module 60 are connected, and at the same time, the passage between the positive pressure module 60 and the negative pressure module 50 is ensured to be closed. Then, the positive pressure module 60 starts to work, and the air pressure inside the first accommodation chamber gradually increases by delivering gas to the first accommodation chamber of the main ink cartridge 20 or adopting other mechanisms that can generate positive pressure (such as compressed air input, etc.), thereby generating a positive pressure environment. The generated positive pressure will push the ink in the main ink cartridge 20 to flow to the nozzle and other components that need ink supply.

[0037] During the printing process, the pressure state of the main ink cartridge 20 needs to be switched according to different working conditions. For example, in the ink replenishing stage, it is necessary to generate negative pressure on the main ink cartridge 20 to better absorb ink from the ink barrel. At this time, the main ink cartridge positive and negative pressure switching valve 40 is operated to connect the main ink cartridge 20 with the negative pressure module 50, and the passage with the positive pressure module 60 is closed, so that the negative pressure module 50 generates negative pressure on the first accommodation chamber of the main ink cartridge 20.

[0038] When the ink is replenished, the ink needs to be stably delivered to the nozzle for printing, and the positive pressure state needs to be switched to. The positive and negative pressure switching valve 40 of the main ink cartridge is operated again to open the passage with the positive pressure and close the passage with the negative pressure module 50, so that the positive pressure module 60 generates positive pressure on the first receiving chamber of the main ink cartridge 20, pushing the ink to flow to the nozzle.

[0039] In some embodiments, see Figure 3 The positive pressure module 60 includes: a positive pressure tank 61 and a first air pressure regulating module 62. The positive pressure tank 61 is connected to the second end of the main ink cartridge positive and negative pressure switching valve 40. The first air pressure regulating module 62 is connected to the positive pressure tank 61, and the first air pressure regulating module 62 regulates the air pressure in the positive pressure tank 61 to positive pressure.

[0040] In some embodiments, see Figure 4 , the first air pressure regulating module 62 includes: a first vacuum pump 624, a low positive pressure valve 622, a low negative pressure valve 621, and a positive pressure tank pressure relief valve 623. Among them, the first vacuum pump 624 is used to compress the external gas into the positive pressure tank 61 so that the air pressure in the positive pressure tank 61 is positive pressure, or to evacuate the positive pressure tank 61 to reduce the positive pressure in the positive pressure tank 61. The first end of the low positive pressure valve 622 is connected to the positive pressure tank 61, and the second end of the low positive pressure valve 622 is connected to the first vacuum pump 624. The low positive pressure valve 622 is used to open or close the passage between the air outlet of the first vacuum pump 624 and the positive pressure tank 61. The first end of the low negative pressure valve 621 is connected to the positive pressure tank 61, and the second end of the low negative pressure valve 621 is connected to the first vacuum pump 624. The low negative pressure valve 621 is used to open or close the passage between the air inlet of the first vacuum pump 624 and the positive pressure tank 61. The positive pressure tank pressure relief valve 623 is connected to the positive pressure tank 61 , and the positive pressure tank pressure relief valve 623 is used to reduce the positive pressure in the positive pressure tank 61 .

[0041] Among them, low positive pressure is relative to standard atmospheric pressure and high positive pressure. Standard atmospheric pressure is about 101.325 kPa (kilopascals). Positive pressure refers to the situation where the pressure is higher than the surrounding atmospheric pressure. Low positive pressure refers to the pressure slightly higher than atmospheric pressure, and the pressure value is generally relatively small.

[0042] Specifically, when positive pressure needs to be generated, the first vacuum pump 624 starts working. First, the low positive pressure valve 622 is opened and the low negative pressure valve 621 is closed. The first vacuum pump 624 inhales gas from the external environment and then compresses the gas. The compressed gas enters the positive pressure tank 61 through the opened low positive pressure valve 622, so that the air pressure in the positive pressure tank 61 gradually increases, thereby generating positive pressure. This process is similar to inflating a balloon with an air pump. The first vacuum pump 624 is the power source for inflating, and continuously compresses the external gas and transports it to the positive pressure tank 61. During the positive pressure generation process, the positive pressure tank pressure relief valve 623 is in a closed state to ensure that the air pressure in the positive pressure tank 61 can continue to rise. When the air pressure in the positive pressure tank 61 reaches the required positive pressure value, the first vacuum pump 624 can stop working and the low positive pressure valve 622 is closed. At this time, the positive pressure in the positive pressure tank 61 needs to remain stable. If the pressure sensor detects that the pressure in the positive pressure tank 61 has a downward trend, the first vacuum pump 624 can work again to replenish gas to maintain the positive pressure; or by adjusting the opening of the positive pressure tank pressure relief valve 623, the gas leakage and replenishment in the positive pressure tank 61 can be balanced to stabilize the positive pressure.

[0043] When the positive pressure in the positive pressure tank 61 needs to be reduced, the working mode of the first vacuum pump 624 is changed. At this time, the low negative pressure valve 621 is opened and the low positive pressure valve 622 is closed. The first vacuum pump 624 starts to extract gas from the positive pressure tank 61. As the gas is extracted, the gas pressure in the positive pressure tank 61 gradually decreases.

[0044] The positive pressure tank pressure relief valve 623 can also be used to reduce the positive pressure. When the positive pressure needs to be reduced quickly or the pressure in the positive pressure tank 61 is too high, the positive pressure tank pressure relief valve 623 opens, and the gas in the positive pressure tank 61 is directly discharged to the external environment, thereby quickly reducing the air pressure in the positive pressure tank 61. In actual operation, the air extraction function of the first vacuum pump 624 or the pressure relief function of the positive pressure tank pressure relief valve 623 can be used alone or in combination to achieve an ideal positive pressure reduction effect.

[0045] In this embodiment, the positive pressure of the main ink cartridge 20 is precisely controlled by the first vacuum pump 624 , the low positive pressure valve 621 , and the positive pressure tank pressure relief valve 623 to control the low positive pressure in the positive pressure tank.

[0046] In some embodiments, see Figure 5 The negative pressure module 50 includes: a negative pressure tank 51 and a second air pressure regulating module 52. The negative pressure tank 51 is connected to the second end of the auxiliary ink cartridge switch valve 30 and the third end of the main ink cartridge positive and negative pressure switch valve 40 respectively. The second air pressure regulating module 52 is connected to the negative pressure tank 51, and the second air pressure regulating module 52 regulates the air pressure in the negative pressure tank 51 to negative pressure.

[0047] In some embodiments, see Figure 6The second air pressure regulating module 52 includes: a second vacuum pump 522, a negative pressure tank switch valve 521, and a negative pressure tank pressure relief valve 523. The second vacuum pump 522 is used to evacuate the negative pressure tank 51 so that the air pressure in the negative pressure tank 51 is negative pressure. The first end of the negative pressure tank switch valve 521 is connected to the negative pressure tank 51, and the second end of the negative pressure tank switch valve 521 is connected to the second vacuum pump 522. The negative pressure tank switch valve 521 is used to open or close the passage between the second vacuum pump 522 and the negative pressure tank 51. The negative pressure tank pressure relief valve 523 is connected to the negative pressure tank 51, and the negative pressure tank pressure relief valve 523 is used to reduce the negative pressure in the negative pressure tank 51.

[0048] Specifically, when it is necessary to generate negative pressure in the negative pressure tank 51, the negative pressure tank switch valve 521 is opened to form a passage between the negative pressure tank 51 and the second vacuum pump 522. The second vacuum pump 522 starts to work, and it extracts gas from the negative pressure tank 51 through the negative pressure tank switch valve 521. As the gas is continuously extracted, the number of gas molecules in the negative pressure tank 51 decreases, the air pressure gradually decreases, and the air pressure in the container will be lower than the external atmospheric pressure, thereby generating negative pressure.

[0049] When the air pressure in the negative pressure tank 51 reaches the required negative pressure value, the second vacuum pump 522 can stop working and the negative pressure tank switch valve 521 is closed. At this time, the negative pressure in the negative pressure tank 51 remains stable. If the pressure in the negative pressure tank 51 rises due to some reasons (such as a small leak), the second vacuum pump 522 can work again to extract gas to maintain the negative pressure.

[0050] When it is necessary to reduce the negative pressure in the negative pressure tank 51 (for example, to make the pressure in the negative pressure tank 51 close to atmospheric pressure or to perform some maintenance operations), the negative pressure tank pressure relief valve 523 is opened. The air in the external environment will enter the negative pressure tank 51 under the action of the air pressure difference. As the air enters, the air pressure in the negative pressure tank 51 gradually increases, and the degree of negative pressure decreases. By controlling the opening of the negative pressure tank pressure relief valve 523, the speed at which air enters can be adjusted, thereby accurately controlling the speed at which the negative pressure is reduced. For example, if you just need to balance the negative pressure slightly, you only need to slightly open the negative pressure tank pressure relief valve 523 to let a small amount of air in; if you need to quickly restore the negative pressure tank 51 to the atmospheric pressure state, you can fully open the negative pressure tank pressure relief valve 523 to allow air to enter quickly.

[0051] In this embodiment, the negative pressure tank 51 is evacuated by the second vacuum pump 522 , and the negative pressure in the negative pressure tank 51 is precisely controlled by the negative pressure tank switch valve 521 and the negative pressure tank pressure relief valve 523 .

[0052] In some embodiments, see Figure 7The air circuit control device 100 also includes: an air source connection 70, a pressure regulating valve 80, and an ink pressure switching valve 90. Among them, the air source connection 70 is used to filter the input gas. The pressure regulating valve 80 is connected to the air source connection 70, and the pressure regulating valve 80 is used to adjust the air pressure of the input gas. The first end of the ink pressure switching valve 90 is connected to the main ink cartridge 20, the second end of the ink pressure switching valve 90 is connected to the first end of the main ink cartridge positive and negative pressure switching valve 40, the third end of the ink pressure switching valve 90 is connected to the pressure regulating valve 80, and the ink pressure switching valve 90 is used to open or close the passage between the main ink cartridge 20 and the main ink cartridge positive and negative pressure switching valve 40 and / or the pressure regulating valve 80.

[0053] The gas source connection 70 first filters the input gas to remove impurities in the gas, such as dust, moisture, etc. In the gas circuit system of a digital printer, pure gas is very important for maintaining the normal operation of components such as ink cartridges. For example, if impurities enter the positive pressure module or the negative pressure module, it may affect the normal opening and closing of the valve, the working efficiency of the vacuum pump, and even damage related equipment.

[0054] The gas filtered by the gas source connection 70 enters the pressure regulating valve 80. The pressure regulating valve 80 can adjust the gas pressure of the input gas according to the needs of the system. For example, when it is necessary to provide a certain positive pressure gas to the main ink cartridge 20, the pressure regulating valve 80 can adjust the input gas pressure to a suitable value, which can be determined according to the specific working requirements of the main ink cartridge 20 (such as the ink delivery pressure requirement).

[0055] The ink pressure switching valve 90 plays a key role in controlling the passage. When it is necessary to provide positive pressure to the main ink cartridge 20 through the regulated gas, the ink pressure switching valve 90 will open the passage between the main ink cartridge 20 and the pressure regulating valve 80, and at the same time close other passages that may interfere between the main ink cartridge 20 and the main ink cartridge positive and negative pressure switching valve 40. In this way, the pressure-regulated gas can smoothly enter the main ink cartridge 20, provide it with positive pressure, and push the ink in the ink cartridge, for example, playing a role in the ink pressure operation or ink delivery process.

[0056] In some embodiments, the air circuit control device 100 further includes: an ink pressure relief valve 110 . The first end of the ink pressure relief valve 110 is connected to the main ink cartridge 20 , and the second end of the ink pressure relief valve 110 is connected to the ink pressure switching valve 90 . The ink pressure relief valve 110 is used to reduce the positive pressure in the main ink cartridge 20 .

[0057] When the positive pressure in the main ink cartridge 20 is too high, or when the positive pressure in the main ink cartridge 20 needs to be reduced after the ink pressing is completed, the ink pressing pressure relief valve 110 plays a role. After the ink pressing pressure relief valve 110 is opened, the gas in the main ink cartridge 20 can be discharged through the valve, thereby reducing the positive pressure in the main ink cartridge 20.

[0058] See also Figure 8Specifically, the gas source connection element 70 includes a filter 71, a pressure reducing valve 72 and an oil mist separator 73. In this embodiment, the gas input from the external gas source passes through the filter 71, the pressure reducing valve 72 and the oil mist separator 73 in sequence, and the input gas can be filtered.

[0059] In this embodiment, when the nozzle is blocked due to a large amount of dust on the cardboard after a long period of printing, or when performing maintenance after printing, a momentary pressure can be applied to the nozzle 300 to maintain the nozzle 300. At this time, the low positive pressure in the positive pressure tank 61 needs to be converted into a pressure adjusted by the pressure regulating valve 80. Specifically, the ink pressing operation is performed by switching the ink pressing switching valve 90. At the same time, a relative vacuum is formed in the auxiliary ink cartridge 10, that is, the auxiliary ink cartridge switching valve 30 is controlled to be closed, so that a corresponding closed space is formed at the outlet end of the nozzle 300. At this time, when a pressure is applied through the pressure regulating valve 80, since there is still a certain negative pressure in the auxiliary ink cartridge 10, a part of the ink will go out from the outlet end of the nozzle 300 to take away the stubborn sediment that was not taken away during the circulation process, and at the same time, a part of the ink will come out from the nozzle hole of the nozzle 300 to clean the nozzle hole and the nozzle surface.

[0060] After the ink pressing is completed, the ink pressing pressure relief valve 110 needs to be controlled to release the pressure on the main ink cartridge 20 to reduce the pressure in the main ink cartridge 20 to 0. Then, the main ink cartridge 20 is controlled to be connected to the positive pressure tank 61 again.

[0061] See also Fig. 9 , Fig. 9 It is a schematic diagram of the structure of the gas path control device 100 provided in other embodiments of the present application.

[0062] In some embodiments, the number of the main ink cartridges 20 is N, where N is a positive integer. When the number of the main ink cartridges 20 is N, the number of the auxiliary ink cartridges 10, the positive pressure module 60, the negative pressure module 50, the auxiliary ink cartridge switch valve 30, the main ink cartridge positive and negative pressure switch valve 40, the ink pressure switch valve 90, and the ink pressure relief valve 110 are all N, and the number of the air source connector 70 and the pressure regulating valve 80 is one.

[0063] Among them, a pair of ink cartridges 10 is connected to a negative pressure module 50 through a pair of ink cartridge switching valve 30, and a main ink cartridge 20 is connected to a positive pressure module 60 through a pressure ink relief valve 110, a pressure ink switching valve 90, and a main ink cartridge positive and negative pressure switching valve 40 in sequence. A main ink cartridge positive and negative pressure switching valve 40 is also connected to a negative pressure module 50, and each pressure ink switching valve 90 is also connected to a pressure regulating valve 80.

[0064] Specifically, inks of different colors can be circulated in each main ink cartridge. Fig. 9 Taking four main ink cartridges as an example, each main ink cartridge can share one air source connection component 70 and one pressure regulating valve 80 to perform ink pressing processing respectively.

[0065] In some embodiments, the gas path control device 100 further includes: a detection module (not shown) and a controller (not shown).

[0066] Among them, the detection module includes a first liquid level sensor (not shown in the figure), a second liquid level sensor (not shown in the figure), a first pressure sensor (not shown in the figure), and a second pressure sensor (not shown in the figure). The first liquid level sensor and the first pressure sensor are both arranged in the main ink cartridge 20, and the second liquid level sensor and the second pressure sensor are both arranged in the auxiliary ink cartridge 10. The first liquid level sensor is used to measure the first liquid level value in the main ink cartridge 20, and the second liquid level sensor is used to measure the second liquid level value in the auxiliary ink cartridge 10. The first pressure sensor is used to measure the first air pressure value in the main ink cartridge 20, and the second pressure sensor is used to measure the second air pressure value in the auxiliary ink cartridge 10.

[0067] The controller is respectively connected to the first liquid level sensor, the second liquid level sensor, the first pressure sensor, the second pressure sensor, the positive pressure module 60, the negative pressure module 50, the auxiliary ink cartridge switch valve 30, and the main ink cartridge positive and negative pressure switching valve 40. The controller is used to control the positive pressure module 60, the negative pressure module 50, the auxiliary ink cartridge switch valve 30, and the main ink cartridge positive and negative pressure switching valve 40 to adjust the air pressure of the main ink cartridge 20 and the auxiliary ink cartridge 10 according to the first liquid level value, the second liquid level value, the first air pressure value, and the second air pressure value.

[0068] Specifically, Figure 1 As shown, the controller can control the operation of the circulation pump 200 and the spray head 300. Figure 8 As shown, the controller can also control the operation of the auxiliary ink cartridge switch valve 30, the main ink cartridge positive and negative pressure switch valve 40, the negative pressure tank switch valve 521, the second vacuum pump 522, the negative pressure tank pressure relief valve 523, the low negative pressure valve 621, the low positive pressure valve 622, the positive pressure tank pressure relief valve 623, the first vacuum pump 624, the air source connection 70, the pressure regulating valve 80, the ink pressure switch valve 90, and the ink pressure relief valve 110.

[0069] The following combination Figure 8 The working principle of the gas path control device 100 is briefly described.

[0070] In actual application, the negative pressure of the auxiliary ink cartridge 10 is controlled by vacuumizing the negative pressure tank 51 through the second vacuum pump 522, and the negative pressure tank switch valve 521 and the negative pressure tank pressure relief valve 523 are used to accurately control the negative pressure in the negative pressure tank 10. The positive pressure of the main ink cartridge 20 is controlled by the first vacuum pump 624, the low positive pressure valve 622 and the positive pressure tank pressure relief valve 623 to accurately control the low positive pressure in the positive pressure tank 20.

[0071] In the process of switching from the circulation state to the pressure-maintaining state, the positive pressure of the main ink cartridge 20 will slowly turn into negative pressure, and the negative pressure of the auxiliary ink cartridge 10 will slowly decrease, in order to prevent the nozzle 300 from sucking back air and the nozzle 300 from dripping ink. At this time, the changes in the positive and negative pressures in the auxiliary ink cartridge 10 and the main ink cartridge 20 need to be maintained in a linear relationship. The positive pressure tank pressure relief valve 623 and the negative pressure tank pressure relief valve 523 will release pressure at the same time by controlling their switches, and control the relationship between the positive pressure and the negative pressure drop. Then, when the negative pressure tank 51 is depressurized to 0, the auxiliary ink cartridge 10 will continue to reduce the negative pressure. At this time, the main ink cartridge 20 needs to use the first vacuum pump 624, the low negative pressure valve 621 and the positive pressure tank pressure relief valve 623 to pump negative pressure from the positive pressure tank 61, so that the negative pressure of the main ink cartridge 20 slowly rises. At this time, the negative pressure rising speed of the main ink cartridge 20 is still controlled to be linearly related to the negative pressure falling speed of the auxiliary ink cartridge 10, so as to achieve precise control of the nozzle 300. The principle of switching from normal standby state to circulation state is similar to that of normal standby state, which will not be described here. Thus, in the process of switching from circulation state to holding state, and in the process of holding state to circulation state, the nozzle remains in good condition and production can continue without maintenance.

[0072] After the circulation state is switched to the pressure-holding state, that is, during the pressure-holding state, the negative pressures of the main ink cartridge 20 and the auxiliary ink cartridge 10 are consistent. In order to better ensure the stability of the printhead, it is best to use the same negative pressure tank for the negative pressure control of the main ink cartridge 20 and the auxiliary ink cartridge 10, so that unstable printing will not be caused by the negative pressure fluctuation in the two negative pressure tanks. At this time, the negative pressure of the main ink cartridge 20 needs to be connected to the negative pressure tank 51 through the main ink cartridge positive and negative pressure tank switching valve 40, so that the main ink cartridge 20 and the auxiliary ink cartridge 10 share a negative pressure tank. Therefore, when in a long-term pressure-holding state, the stability of the printhead will not be affected.

[0073] In addition, when the nozzle 300 is blocked by a large amount of dust on the cardboard after a long period of printing, or when performing maintenance after printing, a momentary pressure can be applied to the nozzle 300 to maintain the nozzle 300. At this time, the low positive pressure in the positive pressure tank 61 needs to be converted into a pressure adjusted by the pressure regulating valve 80. Specifically, the ink pressing operation is performed by switching the ink pressing switching valve 90. At the same time, a relative vacuum is formed in the auxiliary ink cartridge 10, that is, the auxiliary ink cartridge switching valve 30 is controlled to be closed, so that a corresponding closed space is formed at the outlet end of the nozzle 300. At this time, when a pressure is applied through the pressure regulating valve 80, since there is still a certain negative pressure in the auxiliary ink cartridge 10, a part of the ink will go out from the outlet end of the nozzle 300 to take away the stubborn sediment that was not taken away during the circulation process, and at the same time, a part of the ink will come out from the nozzle of the nozzle 300 to clean the nozzle and the nozzle surface.

[0074] After the ink pressing is completed, the ink pressing pressure relief valve 110 needs to be controlled to release the pressure of the main ink cartridge 20, and the pressure in the main ink cartridge 20 becomes 0. Then, the main ink cartridge 20 is controlled to be connected with the positive pressure tank 61 again, and slowly changes to a circulation state, and then cooperates with the mechanical ink scraping to enter the printing state.

[0075] The above work can be controlled by the controller. Specifically, the controller obtains the air pressure value and the liquid level value in the main ink cartridge and the auxiliary ink cartridge through the first liquid level sensor, the second liquid level sensor, the first pressure sensor, and the second pressure sensor, and controls the air pressure in the main ink cartridge and the auxiliary ink cartridge according to the air pressure value and the liquid level value in the main ink cartridge and the auxiliary ink cartridge. For example, in the process of switching from the circulation state to the pressure holding state, the negative pressure rising speed of the main ink cartridge 20 is still linearly related to the negative pressure falling speed of the auxiliary ink cartridge 10, etc.

[0076] In the air path control device provided in the embodiment of the present application, when it is necessary to generate positive pressure in the first accommodating chamber of the main ink cartridge, the positive and negative pressure switching valve of the main ink cartridge switches the passage. The passage between the first end (connected to the main ink cartridge) and the second end (connected to the positive pressure module) is opened, and at the same time, the passage with the third end (connected to the negative pressure module) is ensured to be closed. The positive pressure module starts to work, injects gas into the first accommodating chamber of the main ink cartridge or increases the pressure in the cavity in other ways, so that positive pressure is generated in the first accommodating chamber. For the generation of negative pressure in the first accommodating chamber of the main ink cartridge, the positive and negative pressure switching valve of the main ink cartridge opens the passage between the first end and the third end, and at the same time closes the passage with the second end. The negative pressure module performs a vacuum operation on the first accommodating chamber of the main ink cartridge through the passage, so that the air pressure in the cavity is reduced to form a negative pressure.

[0077] When negative pressure is generated in the second receiving chamber of the auxiliary ink cartridge, the auxiliary ink cartridge switch valve is opened to connect the passage between the auxiliary ink cartridge and the negative pressure module. The negative pressure module evacuates the second receiving chamber of the auxiliary ink cartridge to reduce the air pressure in the chamber. Negative pressure has many uses in the ink cartridge system. For example, during the ink replenishment stage, negative pressure can be used to more smoothly draw ink from the external storage container into the ink cartridge.

[0078] The design of the main ink cartridge positive and negative pressure switching valve and the auxiliary ink cartridge switch valve can flexibly adapt to different working scenarios. For example, under different printing tasks, the ink supply and system operation can be optimized, improving the versatility and adaptability of the device. In addition, by controlling the positive and negative pressures, the different working states of the printhead can be accurately converted, thereby reducing material loss and improving production efficiency.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Under the concept of the present application, the technical features in the above embodiments or different embodiments may also be combined, the steps may be implemented in any order, and there are many other changes in different aspects of the present application as described above, which are not provided in detail for the sake of simplicity. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A gas path control device, characterized in that: The gas path control device comprises: A main ink cartridge, the main ink cartridge comprising a first accommodating chamber; A secondary ink cartridge, the secondary ink cartridge comprising a second accommodating chamber; A positive pressure module, the positive pressure module is used to generate positive pressure in the first containing chamber; A negative pressure module, the negative pressure module is used to generate negative pressure in the first accommodating chamber and / or the second accommodating chamber; A secondary ink cartridge switch valve, wherein a first end of the secondary ink cartridge switch valve is connected to the secondary ink cartridge, a second end of the secondary ink cartridge switch valve is connected to the negative pressure module, and the secondary ink cartridge switch valve is used to open or close a passage between the secondary ink cartridge and the negative pressure module; A main ink cartridge positive and negative pressure switching valve, wherein the first end of the main ink cartridge positive and negative pressure switching valve is connected to the main ink cartridge, the second end of the main ink cartridge positive and negative pressure switching valve is connected to the positive pressure module, and the third end of the main ink cartridge positive and negative pressure switching valve is connected to the negative pressure module. The main ink cartridge positive and negative pressure switching valve is used to open or close the passage between the main ink cartridge and the positive pressure module and / or the negative pressure module.

2. The gas path control device according to claim 1, characterized in that: The positive pressure module comprises: A positive pressure tank connected to the second end of the positive and negative pressure switching valve of the main ink cartridge; A first air pressure regulating module, wherein the first air pressure regulating module is connected to the positive pressure tank, and the first air pressure regulating module regulates the air pressure in the positive pressure tank to a positive pressure.

3. The gas path control device according to claim 2, characterized in that: The first air pressure regulating module comprises: a first vacuum pump, the first vacuum pump being used to compress external gas into the positive pressure tank so that the gas pressure in the positive pressure tank is positive pressure, or to evacuate the positive pressure tank to reduce the positive pressure in the positive pressure tank; A low positive pressure valve, wherein a first end of the low positive pressure valve is connected to the positive pressure tank, a second end of the low positive pressure valve is connected to the first vacuum pump, and the low positive pressure valve is used to open or close a passage between an air outlet of the first vacuum pump and the positive pressure tank; A low negative pressure valve, wherein a first end of the low negative pressure valve is connected to the positive pressure tank, a second end of the low negative pressure valve is connected to the first vacuum pump, and the low negative pressure valve is used to open or close a passage between an air inlet of the first vacuum pump and the positive pressure tank; A positive pressure tank pressure relief valve is connected to the positive pressure tank and is used to reduce the positive pressure in the positive pressure tank.

4. The gas path control device according to claim 1, characterized in that: The negative pressure module comprises: A negative pressure tank, the negative pressure tank is respectively connected to the second end of the auxiliary ink cartridge switch valve and the third end of the main ink cartridge positive and negative pressure switch valve; The second air pressure regulating module is connected to the negative pressure tank, and the second air pressure regulating module regulates the air pressure in the negative pressure tank to negative pressure.

5. The gas path control device according to claim 4, characterized in that: The second air pressure regulating module comprises: a second vacuum pump, the second vacuum pump being used to evacuate the negative pressure tank so that the air pressure in the negative pressure tank is negative pressure; A negative pressure tank switch valve, wherein a first end of the negative pressure tank switch valve is connected to the negative pressure tank, a second end of the negative pressure tank switch valve is connected to the second vacuum pump, and the negative pressure tank switch valve is used to open or close a passage between the second vacuum pump and the negative pressure tank; A negative pressure tank pressure relief valve, wherein the negative pressure tank pressure relief valve is connected to the negative pressure tank, and the negative pressure tank pressure relief valve is used to reduce the negative pressure in the negative pressure tank.

6. The gas path control device according to claim 1, characterized in that: The gas path control device also includes: A detection module, the detection module includes a first liquid level sensor, a second liquid level sensor, a first pressure sensor, and a second pressure sensor, the first liquid level sensor and the first pressure sensor are both arranged in the main ink cartridge, the second liquid level sensor and the second pressure sensor are both arranged in the auxiliary ink cartridge, the first liquid level sensor is used to measure a first liquid level value in the main ink cartridge, the second liquid level sensor is used to measure a second liquid level value in the auxiliary ink cartridge, the first pressure sensor is used to measure a first air pressure value in the main ink cartridge, and the second pressure sensor is used to measure a second air pressure value in the auxiliary ink cartridge; A controller, wherein the controller is respectively connected to the first liquid level sensor, the second liquid level sensor, the first pressure sensor, the second pressure sensor, the positive pressure module, the negative pressure module, the auxiliary ink cartridge switch valve, and the main ink cartridge positive and negative pressure switching valve, and the controller is used to control the positive pressure module, the negative pressure module, the auxiliary ink cartridge switch valve, and the main ink cartridge positive and negative pressure switching valve to adjust the air pressure of the main ink cartridge and the auxiliary ink cartridge according to the first liquid level value, the second liquid level value, the first air pressure value, and the second air pressure value.

7. The gas path control device according to any one of claims 1 to 6, characterized in that: The gas path control device also includes: An air source connection piece, the air source connection piece is used to filter the input gas; A pressure regulating valve, the pressure regulating valve is connected to the gas source connection piece, and the pressure regulating valve is used to adjust the gas pressure of the input gas; An ink pressure switching valve, wherein the first end of the ink pressure switching valve is connected to the main ink cartridge, the second end of the ink pressure switching valve is connected to the first end of the positive and negative pressure switching valve of the main ink cartridge, the third end of the ink pressure switching valve is connected to the pressure regulating valve, and the ink pressure switching valve is used to open or close the passage between the main ink cartridge and the positive and negative pressure switching valve of the main ink cartridge and / or the pressure regulating valve.

8. The gas path control device according to claim 7, characterized in that: The gas path control device also includes: An ink pressure relief valve, wherein the first end of the ink pressure relief valve is connected to the main ink cartridge, the second end of the ink pressure relief valve is connected to the ink pressure switching valve, and the ink pressure relief valve is used to reduce the positive pressure in the main ink cartridge.

9. The gas path control device according to claim 8, characterized in that: The number of the main ink cartridges is N, where N is a positive integer. When the number of the main ink cartridges is N, the number of the auxiliary ink cartridges, the positive pressure module, the negative pressure module, the auxiliary ink cartridge switch valve, the main ink cartridge positive and negative pressure switching valve, the ink pressure switching valve, and the ink pressure relief valve are all N, and the number of the air source connector and the pressure regulating valve is one; Among them, a pair of ink cartridges is connected to a negative pressure module through a pair of ink cartridge switching valve, and a main ink cartridge is connected to a positive pressure module through a pressure ink relief valve, a pressure ink switching valve, and a main ink cartridge positive and negative pressure switching valve in sequence. The main ink cartridge positive and negative pressure switching valve is also connected to the negative pressure module, and each of the pressure ink switching valves is also connected to the pressure regulating valve.

10. A digital printer, characterized in that: The digital printer comprises: a nozzle, a circulation pump, an ink barrel and an air path control device as claimed in any one of claims 1 to 9; Wherein, the main ink cartridge is connected to the nozzle, the circulation pump and the ink barrel respectively, and the auxiliary ink cartridge is connected to the nozzle and the circulation pump respectively.

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