An ink circulation control method and system

Abstract

The application discloses a kind of ink supply circulation control method and system, ink circulation system technical field is related, including the following steps: first heater in secondary ink bucket heats the ink in secondary ink bucket, suction stirring assembly drives the circulation flow of ink in secondary ink bucket;Ink in secondary ink bucket is driven by ink supply pump to pass through degassing damping component, second heater and buffer portion in turn, third heater heats the ink in buffer portion, and the ink in buffer portion can flow back to secondary ink bucket;According to ink temperature, the viscosity of ink in ink supply pump and the volume flow Q output by ink supply pump are determined, the power of first heater remains unchanged, the power of second heater and third heater is calculated, second heater heats the temperature of ink to, and third heater heats the temperature of ink to, wherein, the optimum temperature for printing of ink, x is in the range of 1 to 4.The application can accurately control the temperature of ink, and improve printing effect.

Description

Technical Field

[0001] This invention relates to the field of ink circulation system technology, and in particular to an ink supply circulation control method and system. Background Technology

[0002] In the field of lithium battery insulating coating printing, UV inks are commonly used. UV inks are temperature-sensitive, and the temperature stability of the ink supply circulation system directly determines the final printing quality. Key physical parameters of the ink, such as viscosity, flowability, and surface tension, are highly dependent on temperature. Even small temperature fluctuations can lead to uneven ink distribution, poor ink dripping, or even printhead clogging, resulting in defects such as streaks and color differences in the printed pattern, severely reducing product yield. Existing ink supply systems typically heat the ink by wrapping a heating belt or heating plate around the ink tank and using a simple temperature sensor for closed-loop control. However, this single heating method has significant drawbacks: First, the ink temperature can drop unpredictably after flowing through the ink pump, long-distance pipelines, and degassing unit, causing the ink temperature reaching the printhead to deviate from the set range. Second, traditional heating methods indirectly heat the ink by heating the container wall, resulting in a significant temperature gradient within the container—the ink near the wall is too hot, while the ink in the center is too cold, creating temperature stratification. This means that the temperature measurement at a single point cannot accurately reflect the overall ink temperature, leading to low temperature control accuracy. Summary of the Invention

[0003] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes an ink supply circulation system that can improve the problem of low ink temperature control accuracy and improve printing results.

[0004] According to a first aspect of the present invention, an ink supply circulation control method includes the following steps: a first heater in a secondary ink tank heats the ink in the secondary ink tank, and a suction and stirring assembly drives the ink in the secondary ink tank to circulate.

[0005] The ink supply pump drives the ink in the secondary ink tank to pass sequentially through the degassing damping component, the second heater, and the buffer section. The third heater heats the ink in the buffer section, and the ink in the buffer section can flow back to the secondary ink tank.

[0006] The ink temperature T1 inside the secondary ink tank is obtained, the ink temperature T2 at the inlet of the buffer section is obtained, and the ink temperature T3 at the outlet of the buffer section is obtained.

[0007] A first correspondence between ink viscosity and ink temperature is established in advance, and a second correspondence between ink viscosity and volumetric flow rate Q output by the ink supply pump (400) is established in advance;

[0008] The ink viscosity corresponding to the ink temperature T1 in the secondary ink tank is determined according to the first correspondence; the volumetric flow rate Q output by the ink supply pump (400) corresponding to the ink viscosity is determined according to the second correspondence. The power of the first heater remains unchanged, and the power P2 of the second heater is calculated. The formula for calculating P2 is: Calculate the heating power P3 of the third heater. The formula for calculating P3 is: ;

[0009] in, ρ For ink density, c For the specific heat capacity of ink, The optimal temperature for ink printing is x, which ranges from 1 to 4.

[0010] According to a second aspect of the present invention, an ink supply circulation system includes: a secondary ink tank, a suction and stirring assembly, an ink supply pump, a degassing damping assembly, a second heater, and a buffer section. The secondary ink tank is connected to a first heater for heating the ink within the secondary ink tank; the suction and stirring assembly drives the ink within the secondary ink tank to circulate; the inlet of the ink supply pump is connected to the secondary ink tank; the degassing damping assembly is connected to the outlet of the ink supply pump; the second heater is connected to the degassing damping assembly for heating the ink flowing through the second heater; the inlet of the buffer section is connected to the second heater, the outlet of the buffer section is connected to the secondary ink tank, the buffer section is connected to a third heater for heating the ink in the buffer section, the buffer section receives ink from the second heater, and the ink in the buffer section can flow back to the secondary ink tank.

[0011] According to an embodiment of the present invention, an ink supply circulation system has at least the following beneficial effects: the ink flow is driven by a suction and stirring component to ensure that the ink temperature is as uniform as possible throughout the secondary ink tank; the ink air bubbles and pressure fluctuations are removed by a degassing and damping component. The first heater, the second heater, and the third heater at the bottom of the buffer section around the secondary ink tank work together to ensure that the ink remains within a preset temperature range throughout the entire circulation process. This multi-stage coordinated temperature control effectively offsets ambient temperature fluctuations and heat loss during the process, resulting in stable ink flow during printing.

[0012] According to some embodiments of the present invention, the buffer section has an ink supply chamber and an ink return chamber formed inside it. The inlet of the buffer section is connected to the ink supply chamber, and the outlet of the buffer section is connected to the ink return chamber. The ink supply chamber is connected to a printhead inlet pipe, and the ink return chamber is connected to a printhead outlet pipe. The ink supply chamber is provided with a first pressure sensor and a first temperature sensor, and the ink return chamber is provided with a second pressure sensor and a second temperature sensor.

[0013] According to some embodiments of the present invention, the ink supply chamber is provided with a first turbulence section, and the ink return chamber is provided with a second turbulence section. The first turbulence section and the second turbulence section are used to reduce the pressure fluctuation of the ink in the buffer section.

[0014] According to some embodiments of the present invention, the outlet of the buffer section is connected to the secondary ink tank via a return ink pipe. The return ink pipe is provided with a return ink filter, a second damper, and a return ink pump. The return ink pump is used to deliver the ink in the return ink pipe to the secondary ink tank.

[0015] According to some embodiments of the present invention, the ink supply pump inlet is connected to the secondary ink tank through an ink supply pipe, the ink supply pipe is connected to a vent pipe, the vent pipe is connected to the outside atmosphere through a vent filter, and a vent valve is provided between the vent filter and the vent pipe.

[0016] According to some embodiments of the present invention, the degassing damping assembly includes a first damper and a degassing tank. The first damper receives ink from the ink supply pump. After the ink passes through the first damper to reduce pressure fluctuations, it enters the degassing tank to remove gas from the ink. The degassing tank is connected to a vacuum pump, which is used to extract gas from the degassing tank.

[0017] According to some embodiments of the present invention, the suction and stirring assembly includes an ink extraction tube, an ink delivery tube, and a stirring pump. The ink extraction tube and the ink delivery tube are both connected to the secondary ink tank. The stirring pump extracts ink from the secondary ink tank through the ink extraction tube and delivers the ink to the secondary ink tank through the ink delivery tube.

[0018] According to some embodiments of the present invention, a drain pipe is connected to the bottom of the secondary ink tank, and a drain valve is provided on the drain pipe, which is used to discharge the ink in the secondary ink tank.

[0019] According to some embodiments of the present invention, the secondary ink tank is connected to a spray unit and an ultrasonic transducer. The spray unit is installed on the inner top wall of the secondary ink tank and is used to inject cleaning fluid into the secondary ink tank. The ultrasonic transducer is connected to the lower end of the secondary ink tank and can drive the secondary ink tank to vibrate.

[0020] According to some embodiments of the present invention, the secondary ink tank is connected to an ink replenishment pump, the ink replenishment pump is connected to a primary ink tank, and the ink replenishment pump is used to draw ink from the primary ink tank to the secondary ink tank.

[0021] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0023] Figure 1 This is a schematic diagram of the housing mounting structure according to an embodiment of the present invention;

[0024] Figure 2 for Figure 1 A schematic diagram of the structure after disassembling part of the outer shell.

[0025] Figure 3 This is a schematic diagram of a two-stage ink tank according to an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the ink tank cover plate installation structure according to an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the cache section according to an embodiment of the present invention;

[0028] Figure 6 This is an exploded view of the buffer section according to an embodiment of the present invention;

[0029] Figure 7 This is a schematic diagram showing the connection of a replenishing pump, a primary ink tank, and a secondary ink tank according to an embodiment of the present invention.

[0030] Figure 8 This is a schematic diagram showing the connection of the secondary ink tank, the degassing damping assembly, and the buffer unit according to an embodiment of the present invention.

[0031] Figure 9 This is a schematic diagram showing the connection between the ink supply pump and the vent pipe according to one embodiment of the present invention;

[0032] Figure 10 This is a schematic diagram of a return ink filter and a secondary ink tank according to an embodiment of the present invention;

[0033] Figure 11 This is a schematic diagram showing the connection between the first and second turbulence portions according to an embodiment of the present invention.

[0034] Figure 12 This is a graph showing the relationship between ink viscosity and ink temperature according to an embodiment of the present invention;

[0035] Figure 13 This is a graph showing the relationship between ink viscosity and volumetric flow rate output by the ink supply pump in one embodiment of the present invention.

[0036] Icon labels:

[0037] Secondary ink tank 100, ink tank cover 101, drain pipe 110, drain valve 120, spray unit 130, ultrasonic transducer 140;

[0038] First heater 200;

[0039] Suction and stirring assembly 300, ink extraction tube 310, ink delivery tube 320, flow equalization tube 321, stirring pump 330;

[0040] Ink supply pump 400, ink supply tube 410, vent tube 420, vent filter 430, vent valve 440;

[0041] Degassing damping assembly 500, first damper 510, degassing tank 520, vacuum pump 530;

[0042] Second heater 600;

[0043] The components include: a buffer unit 700, a third heater 701, a buffer cover plate 702, an ink supply chamber 710, a printhead inlet pipe 711, a first pressure sensor 712, a first temperature sensor 713, a first turbulence unit 714, a first turbulence plate 715, a second turbulence plate 716, an ink return chamber 720, a printhead outlet pipe 721, a second pressure sensor 722, a second temperature sensor 723, a second turbulence unit 724, a third turbulence plate 725, and a fourth turbulence plate 726.

[0044] Ink return pipe 800, ink return filter 810, second damper 820, ink return pump 830;

[0045] 900 ink replenishment pump, 910 primary ink tank, 920 ink replenishment filter, 930 chassis. Detailed Implementation

[0046] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0047] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0048] In the description of this invention, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features or their sequential relationship.

[0049] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0050] Reference Figure 2 , Figure 3 , Figure 7 and Figure 8 As shown, an ink supply cycle control method according to an embodiment of the present invention includes:

[0051] The first heater 200 inside the secondary ink tank 100 heats the ink inside the secondary ink tank 100, and the suction and stirring component 300 drives the ink inside the secondary ink tank 100 to circulate.

[0052] The ink supply pump 400 drives the ink in the secondary ink tank 100 to pass through the degassing damping component 500, the second heater 600 and the buffer 700 in sequence. The third heater 701 heats the ink in the buffer 700, and the ink in the buffer 700 can flow back to the secondary ink tank 100.

[0053] Get the ink temperature T1 inside the secondary ink tank 100, get the ink temperature T2 at the inlet of the buffer section 700, and get the ink temperature T3 at the outlet of the buffer section 700.

[0054] A preliminary correlation is established between ink viscosity and ink temperature, either experimentally determined or provided by the ink manufacturer. The relationship between ink viscosity and the volumetric flow rate output by the 400 kcal / h ink pump is also pre-established. Q The second correspondence between them is determined experimentally or provided by the ink manufacturer.

[0055] Taking one type of ink used in the test as an example, the ink viscosity... u The first correspondence between ink temperature and ink temperature is as follows: Figure 12 As shown, ink viscosity u Volumetric flow rate output of ink supply pump 400 Q The second correspondence between them is as follows: Figure 13 As shown.

[0056] The ink viscosity corresponding to the ink temperature T1 in the secondary ink tank is determined based on the first correspondence; the volumetric flow rate output by the ink supply pump 400 corresponding to the ink viscosity is determined based on the second correspondence. Q The power of the first heater 200 remains constant, the power of the second heater 600 is set to P2, and the third heater 701 heats the ink to the specified temperature. The formula for calculating P2 is:

[0057] .

[0058] The power of the third heater 701 is set to P3, and the formula for calculating P3 is:

[0059] .

[0060] in, ρ For ink density, c The ink's specific heat capacity, density, and specific heat capacity were obtained through prior measurement and experimentation. The optimal temperature for ink printing is determined by actual measurement or provided by the ink manufacturer. The value of x ranges from 1 to 4. If the temperature is heated above the optimal ink printing temperature, the third heater 701 cannot further adjust the ink temperature. Therefore, the significance of the x parameter is to ensure that the second heater 600 heats the ink temperature to near the optimal ink printing temperature, leaving a certain temperature margin for the third heater 701 to make fine adjustments.

[0061] Ink viscosity is a key parameter affecting inkjet printing quality, and viscosity is highly sensitive to temperature. The first heater 200 heats the ink in the secondary ink tank 100 at a constant power. To reduce temperature variations between the first heater 200 and the secondary ink tank 100, the first heater 200 can also be controlled to turn on and off using a common temperature control switch. The first heater 200 preheats and maintains a basic, uniform temperature for the ink in the secondary ink tank 100, reducing the power required by the second heater 600 and thus improving its heating accuracy. The second heater 600 acts as feedforward control, calculating the required heat in advance based on the temperature and flow rate of the ink in the secondary ink tank 100. Through predictive heating, it avoids energy waste caused by blind heating. It can quickly respond to disturbances caused by temperature changes in the secondary ink tank 100, reducing system lag. The third heater 701 serves as feedback and fine-tuning control. Based on T3 and the target temperature... The deviation is finely adjusted in real time. The third heater 701 is closer to the printhead, resulting in a faster response and lower thermal inertia. This ensures that the ink temperature delivered to the printhead is precisely controlled at the optimal value.

[0062] Reference Figure 2 , Figure 3 , Figure 7 and Figure 8 As shown, the present invention also provides an ink supply circulation system, including: a secondary ink tank 100, a suction and stirring assembly 300, an ink supply pump 400, a degassing damping assembly 500, a second heater 600, and a buffer unit 700.

[0063] The secondary ink tank 100 is a barrel-shaped structure made of alloy steel. The upper end of the secondary ink tank 100 is open, and a lid 101 is bolted to the upper end. The lid 101 is used to close the opening at the upper end of the secondary ink tank 100. The secondary ink tank 100 is used to store ink. A partition is installed inside the secondary ink tank 100, dividing it into an ink supply space and an ink return space. The lower ends of the ink supply space and the ink return space are connected. The function of the partition is to prevent air bubbles in the ink return space from entering the ink supply space, thus reducing the number of air bubbles entering the ink supply pump 400.

[0064] The secondary ink tank 100 is connected to a first heater 200, which is an electric heating film or an electric heating element, and is arranged around the outer peripheral wall of the secondary ink tank 100. The outer peripheral wall of the secondary ink tank 100 is also provided with an insulation layer, which is made of foamed polyurethane or rock wool. The first heater 200 is located between the insulation layer and the outer peripheral wall of the secondary ink tank 100. The insulation layer is used to reduce heat loss from the secondary ink tank 100 and reduce energy consumption. The first heater 200 is used to heat the side wall of the secondary ink tank 100, thereby indirectly heating the ink inside the secondary ink tank 100.

[0065] One or more ink tank thermometers can be installed on the ink tank cover 101, extending downwards into the secondary ink tank 100. The ink tank thermometers measure the ink temperature inside the secondary ink tank 100. The first heater 200 adjusts its heating power based on the thermometer readings to maintain the ink temperature inside the secondary ink tank 100 within a preset range of 60–95°C. The ink is a UV insulating coating; its fluidity determines the printing effect, and since ink fluidity is temperature-dependent, it is necessary to maintain the ink temperature within the preset range.

[0066] The first heater 200 indirectly heats the ink by heating the side wall of the secondary ink tank 100. Therefore, the ink temperature near the side wall of the secondary ink tank 100 will be higher than the ink temperature far from the side wall of the secondary ink tank 100. The suction and stirring component 300 is used to drive the ink circulation in the secondary ink tank 100. By driving the ink flow, the suction and stirring component 300 makes the ink temperature in all parts of the secondary ink tank 100 as uniform as possible, avoiding temperature stratification and sedimentation in the secondary ink tank 100 due to static heating. This is conducive to accurately and stably controlling the ink temperature entering the ink supply pump 400.

[0067] The inlet of the ink supply pump 400 is connected to the ink supply space in the secondary ink tank 100; the degassing damping assembly 500 is connected to the outlet of the ink supply pump 400. The ink supply pump 400 is a brushless motor-driven double-head diaphragm pump, which has the advantages of large output flow and good output stability. The ink supply pump 400 draws ink from the secondary ink tank 100 and inputs the ink into the degassing damping assembly 500.

[0068] Diaphragm pumps are positive displacement pumps, and the ink output by diaphragm pumps inevitably experiences pressure fluctuations. The degassing damping assembly 500 is used to reduce these pressure fluctuations in the ink as it passes through. The degassing damping assembly 500 also reduces air bubbles in the ink; both air bubbles and pressure fluctuations in the ink affect the uniformity of ink delivery and thus print quality. Therefore, the degassing damping assembly 500 removes air bubbles and pressure fluctuations from the ink.

[0069] The second heater 600 is connected to the degassing damping assembly 500. The second heater 600 is a pipe electric heater used to heat the ink flowing through it. Because the ink temperature drops unpredictably after passing through the degassing damping assembly 500 and the ink supply pump 400, the output ink temperature varies greatly. Therefore, the second heater 600 is provided to keep the ink temperature input to the buffer section 700 stable.

[0070] The inlet of the buffer section 700 is connected to the second heater 600, and the outlet of the buffer section 700 is connected to the secondary ink tank 100. A third heater 701, which is an electric heating element, is located at the bottom of the buffer section 700. The third heater 701 is used to heat the buffer section 700, thereby indirectly heating the ink inside the buffer section 700. The buffer section 700 receives ink from the second heater 600, and the ink in the buffer section 700 can flow back to the ink return space of the secondary ink tank 100. Through three-stage temperature control and insulation, the first heater 200, the second heater 600 around the secondary ink tank 100, and the third heater 701 at the bottom of the buffer section 700 work together to ensure that the ink remains within the preset temperature range throughout the entire circulation process. This multi-stage coordinated temperature control effectively offsets ambient temperature fluctuations and heat loss during the process, ensuring stable ink flow during printing.

[0071] Reference Figure 5 , Figure 6 and Figure 11 As shown, in some embodiments, the buffer section 700 has an ink supply chamber 710 and an ink return chamber 720 formed inside. For ease of manufacturing, the ink supply chamber 710 and ink return chamber 720 are formed directly by slotting into the buffer section 700. Then, the ink supply chamber 710 and ink return chamber 720 are sealed by a buffer cover plate 702 bolted to the top of the buffer section 700. The bolted buffer cover plate 702 allows the ink supply chamber 710 and ink return chamber 720 to be easily opened, facilitating daily cleaning and maintenance.

[0072] The inlet of the buffer section 700 is connected to the ink supply chamber 710, and the outlet of the buffer section 700 is connected to the ink return chamber 720. The ink supply chamber 710 is connected to the printhead inlet pipe 711, and the ink return chamber 720 is connected to the printhead outlet pipe 721. The printhead outlet pipe 721 and the printhead inlet pipe 711 are pipes connected to the printing printhead. The specific structure of the printing printhead is existing technology and will not be described in detail. Ink in the ink supply chamber 710 enters the printing printhead through the printhead inlet pipe 711. The printing printhead ejects part of the ink, and the un-ejected ink enters the ink return chamber 720 through the printhead outlet pipe 721. The ink supply chamber 710 is equipped with a first pressure sensor 712 and a first temperature sensor 713, and the ink return chamber 720 is equipped with a second pressure sensor 722 and a second temperature sensor 723.

[0073] A first temperature sensor 713 and a second temperature sensor 723 are disposed on the buffer cover 702. A first pressure sensor 712 and a second pressure sensor 722 are threadedly connected to the side wall of the buffer section 700. The first temperature sensor 713 passes through the side wall of the buffer section 700 and extends into the ink supply chamber 710, and the second temperature sensor 723 passes through the side wall of the buffer section 700 and extends into the ink return chamber 720. The ink supply circulation system also includes a controller, which is a commonly used industrial programmable logic controller. The first temperature sensor 713, the second temperature sensor 723, the first pressure sensor 712, and the second pressure sensor 722 output the measurement results to the controller.

[0074] The buffer unit 700 integrates ink supply, ink return, pressure monitoring, and temperature monitoring functions into a compact unit. By monitoring the pressure and temperature of the ink supply chamber 710 and the ink return chamber 720 in real time, the controller can adjust the operating status of components such as the ink supply pump 400, the second heater 600, and the third heater 701 in a timely manner to ensure that the pressure and temperature of the ink supplied to the printhead remain within a preset range. Specifically, when the pressure measured by the first pressure sensor 712 and the second pressure sensor 722 is too high, the rotation speed of the ink supply pump 400 is reduced; when the pressure measured by the first pressure sensor 712 and the second pressure sensor 722 is too low, the rotation speed of the ink supply pump 400 is increased. When the temperature measured by the first temperature sensor 713 and the second temperature sensor 723 is too high, the heating power of the second heater 600 and the third heater 701 is reduced; when the temperature measured by the first temperature sensor 713 and the second temperature sensor 723 is too low, the heating power of the second heater 600 and the third heater 701 is increased. The second heater 600 is used for coarse temperature adjustment, and the third heater 701 is used for fine temperature adjustment.

[0075] Reference Figure 5 , Figure 6 and Figure 11As shown, in some embodiments, a first turbulence section 714 is provided in the ink supply chamber 710, and two nozzle inlet pipes 711 are arranged side by side. The first turbulence section 714 includes a first turbulence plate 715 and a second turbulence plate 716. The first turbulence plate 715 and the second turbulence plate 716 are perpendicular to each other. The first turbulence plate 715 is located on the side of the second turbulence plate 716 near the nozzle inlet pipe 711, and the second turbulence plate 716 is perpendicular to the ink flow direction in the ink supply chamber 710.

[0076] The two printhead inlet pipes 711 are symmetrically arranged with the extended plane of the first baffle 715 as the center. When the ink with pressure pulsation impacts the second baffle 716 perpendicular to the flow direction, its kinetic energy is effectively absorbed, making the ink flow and pressure more stable.

[0077] Reference Figure 5 , Figure 6 and Figure 11 As shown, a second turbulence-disrupting section 724 is provided inside the ink return chamber 720. Two printhead outlet pipes 721 are arranged side by side. The second turbulence-disrupting section 724 includes a third turbulence-disrupting plate 725 and a fourth turbulence-disrupting plate 726. The third turbulence-disrupting plate 725 and the fourth turbulence-disrupting plate 726 are perpendicular to each other. The third turbulence-disrupting plate 725 is located on the side of the fourth turbulence-disrupting plate 726 closer to the printhead outlet pipe 721. The fourth turbulence-disrupting plate 726 is perpendicular to the ink flow direction in the ink return chamber 720. The two printhead outlet pipes 721 are symmetrically arranged with the extended plane of the third turbulence-disrupting plate 725 as the center.

[0078] When the pressure-pulsating ink impacts the fourth baffle 726 perpendicular to the flow direction, its kinetic energy is effectively absorbed, making the ink flow and pressure more stable. The first baffle 714 and the second baffle 724 are used to reduce the pressure fluctuation of the ink in the buffer section 700, which can ensure that the ink is evenly distributed to the two parallel printhead inlet pipes 711.

[0079] Reference Figure 9 As shown, in some embodiments, the inlet of the ink pump 400 is connected to the secondary ink tank 100 through the ink supply pipe 410. The ink supply pipe 410 is connected to the vent pipe 420, which is connected to the outside atmosphere through the vent filter 430. A vent valve 440 is provided between the vent filter 430 and the vent pipe 420.

[0080] The vent valve 440 is electrically operated for automated control. Since the diaphragm pump can also deliver gas, when the vent valve 440 is open, the ink supply pipe 410 no longer draws ink from the secondary ink tank 100; instead, air is drawn from the vent pipe 420. This effectively empties the ink supply pipe 410, the degassing damping assembly 500, and the buffer unit 700, facilitating maintenance during downtime. Using air to expel ink prevents residual ink from accumulating in pipes, chambers, and components. This is crucial for easily curing materials, effectively preventing ink from drying and hardening, thus reducing the risk of system failure.

[0081] The vent pipe 420 is connected to the atmosphere through the vent filter 430 to prevent dust, particles and other pollutants in the atmosphere from being sucked into the ink supply pipe 410 during maintenance, thus ensuring printing quality.

[0082] Reference Figure 8 As shown, in some embodiments, the degassing damping assembly 500 includes a first damper 510 and a degassing tank 520. The first damper 510 receives ink from the ink supply pump 400. After the ink passes through the first damper 510 to reduce pressure fluctuations, it enters the degassing tank 520 to eliminate gas in the ink. The first damper 510 reduces the main pressure fluctuations from the ink supply pump 400, avoids liquid level fluctuations in the degassing tank 520, and improves degassing efficiency. The first damper 510 is divided into two compartments. Ink passes through the first compartment under pressure, while the second compartment contains a spring. The two compartments are separated by a diaphragm. The spring is connected to the diaphragm separating the two compartments and is compressed by the ink pressure. When pressure pulsations enter the damper, the spring compresses or expands to counteract the pulsations, thereby reducing the pulse size of the pulsations. The specific structure of the first damper 510 is prior art and is therefore not shown in the figures.

[0083] The degassing tank 520 is connected to a vacuum pump 530, which is used to extract gas from the degassing tank 520. The vacuum pump 530 creates a negative pressure environment inside the degassing tank 520, which can quickly precipitate and remove microbubbles dissolved in the ink. This reduces the pressure fluctuations and bubble content of the ink entering the second heater 600 to a suitable range, reducing printing defects caused by ink pressure fluctuations and bubbles.

[0084] Reference Figure 3As shown, in some embodiments, a drain pipe 110 is connected to the bottom of the secondary ink tank 100. A drain valve 120 is installed on the drain pipe 110, and a drain pump is also installed on the drain pipe 110. The drain pump is used to assist in the discharge of ink from the secondary ink tank 100. The drain pipe 110 is used to discharge the ink from the secondary ink tank 100. Ink may precipitate if left to stand for a long time. Opening the drain valve 120 allows the ink to be conveniently discharged through the drain pipe 110. However, due to the high viscosity of the ink, gravity discharge is slow, so a drain pump is used to force discharge, improving efficiency. The drain pipe 110 can also be used to discharge cleaning fluid injected into the secondary ink tank 100 during cleaning.

[0085] Reference Figure 4 As shown, in some embodiments, the suction and stirring assembly 300 includes an ink extraction pipe 310, an ink delivery pipe 320, and a stirring pump 330. Both the ink extraction pipe 310 and the ink delivery pipe 320 are connected to the secondary ink tank 100. The ink extraction pipe 310 and the ink delivery pipe 320 pass through the ink tank cover plate 101. The lower end of the ink extraction pipe 310 extends to the ink supply space, and the lower end of the ink delivery pipe 320 extends to the ink return space. The stirring pump 330 draws ink from the secondary ink tank 100 through the ink extraction pipe 310 and delivers the ink to the secondary ink tank 100 through the ink delivery pipe 320.

[0086] A stirring pump 330 actively drives the ink to form a circulation loop between the ink supply space and the ink return space of the secondary ink tank 100. The temperature of the ink in the secondary ink tank 100 remains constant. The ink extraction tube 310 and the ink delivery tube 320 are detachably installed on the ink tank cover 101, with a compact structure. During maintenance, the ink extraction tube 310 and the ink delivery tube 320 can be completely disassembled by opening the ink tank cover 101. The lower end of the ink delivery tube 320 is connected to a flow equalization tube 321, which extends horizontally at the bottom of the ink return space. The flow equalization tube 321 has multiple small holes spaced apart. The flow equalization tube 321 receives the ink returning from the ink delivery tube 320. The ink flows out slowly and evenly from the small holes on the flow equalization tube 321, avoiding direct impact of ink from a single outlet on the liquid surface or tank wall.

[0087] Reference Figure 3 and Figure 4As shown, in some embodiments, the secondary ink tank 100 is connected to a spray unit 130 and an ultrasonic transducer 140. The spray unit 130 is installed on the inner top wall of the secondary ink tank 100 and is used to inject cleaning fluid into the secondary ink tank 100. The ultrasonic transducer 140 is connected to the lower end of the secondary ink tank 100 and can drive the secondary ink tank 100 to vibrate. The spray unit 130 is a nozzle detachably connected to the ink tank cover plate 101 and is connected to an external cleaning fluid pipeline. The spray unit 130 uniformly sprays cleaning fluid into the secondary ink tank 100. The cleaning fluid provides a uniform liquid medium for the cavitation effect of the ultrasonic waves. The high-frequency vibration generated by the ultrasonic transducer 140 creates a cavitation effect in the cleaning fluid, generating tiny bubbles that produce impact force when they burst, effectively removing residual solidified ink or stubborn deposits in the secondary ink tank 100. Automated cleaning of the secondary ink tank 100 can be achieved without disassembling the ink tank cover plate 101.

[0088] Reference Figure 10 As shown, in some embodiments, the outlet of the buffer unit 700 is connected to the secondary ink tank 100 via a return ink pipe 800. The return ink pipe 800 is equipped with a return ink filter 810, a second damper 820, and a return ink pump 830. The return ink filter 810 filters out impurities, particles, or slight coagulation that may be carried in the ink circulating from the printhead. The second damper 820 attenuates and absorbs pressure fluctuations in the return ink pipe 800, which may originate from printhead movement or the operation of the return ink pump 830. This prevents pressure waves from being transmitted back from the return ink pump 830 to the buffer unit 700 and the printhead, ensuring stable ink pressure supplied to the printhead. The structure of the second damper 820 is the same as that of the first damper 510.

[0089] The return ink pump 830 is used to deliver ink from the return ink tube 800 to the secondary ink tank 100. The return ink pump 830 provides active and controllable delivery power for the return of ink to the secondary ink tank 100. By adjusting the operating speed of the return ink pump 830, the ink pressure in the return ink chamber 720 can be adjusted. By adjusting the operating speed of the supply ink pump 400, the ink pressure in the supply ink chamber 710 can be adjusted, so that the pressure at the printhead outlet pipe 721 and the printhead inlet pipe 711 is maintained within a preset range.

[0090] Reference Figure 7As shown, in some embodiments, the secondary ink tank 100 is connected to an ink replenishment pump 900, and the secondary ink tank 100 is equipped with a float-type level gauge and a capacitive level gauge. The capacitive level gauge integrates a temperature measurement function. The ink replenishment pump 900 is connected to the primary ink tank 910, and the ink replenishment pump 900 is used to draw ink from the primary ink tank 910 to the secondary ink tank 100. The ink replenishment pump 900 automatically starts and stops according to the liquid level signals measured by the float-type level gauge and the capacitive level gauge, realizing automated ink replenishment from the primary ink tank 910 to the secondary ink tank 100, and automatically maintaining the ink level in the secondary ink tank 100.

[0091] The ink replenishment pump 900 is connected to the secondary ink tank 100 via an ink replenishment filter 920. A one-way valve is installed between the ink replenishment filter 920 and the secondary ink tank 100. The ink replenishment filter 920 intercepts impurity particles from the ink in the primary ink tank 910, ensuring that only clean ink enters the secondary ink tank 100. The ink replenishment filter 920 can be a combination of multiple different types of filters to improve filtration accuracy. The one-way valve ensures that ink can only flow from the ink replenishment filter 920 to the secondary ink tank 100 and cannot flow in the reverse direction, preventing ink from siphoning back to the primary ink tank 910 and causing secondary contamination if the ink level in the secondary ink tank 100 is too high.

[0092] In some embodiments, the ink supply pump 400, return ink pump 830, replenishment ink pump 900, and secondary ink tank 100 are all housed within the chassis 930. The side panel of the chassis 930 has a quick-release structure for easy opening of the chassis 930 for maintenance and cleaning. A touchscreen is provided on the chassis 930 to display temperature and pressure measurement results, and the entire device is controlled via the touchscreen for starting, stopping, and ink discharge. Three indicator lights are also provided on the chassis 930 to display the current operating status of the device. A cooling fan is located on the side of the chassis 930 to cool the interior of the chassis 930.

[0093] The present invention also provides a control method, specifically including the following steps: Ink in the secondary ink tank 100 is maintained at a preset temperature by the first heater 200 and the insulation layer; the suction and stirring assembly 300 continuously drives the ink circulation inside the secondary ink tank 100, ensuring uniform temperature and composition. A partition divides it into ink supply and return spaces, forming an orderly flow. An ink replenishment pump 900 replenishes ink from the primary ink tank 910 to the secondary ink tank 100, maintaining a stable liquid level in the secondary ink tank 100.

[0094] The ink supply pump 400 provides power to pump ink from the secondary ink tank 100 to the degassing damping assembly 500. The ink first passes through the first damper 510 to attenuate pressure fluctuations, and then enters the degassing tank 520. The vacuum pump 530 extracts gas from the tank to create negative pressure, removing microbubbles from the ink.

[0095] After being degassed, the ink enters the buffer section 700 after being temperature compensated by the second heater 600. The third heater 701 at the bottom of the buffer section 700 provides heat preservation for the ink.

[0096] The printhead receives ink from the ink supply chamber 710 for printing. Unused ink from the printhead passes through the ink return chamber 720, then through the ink return filter 810, the second damper 820, and the ink return pump 830 back to the secondary ink tank 100, completing a full cycle.

[0097] The cleaning steps for the secondary ink tank 100 during maintenance are as follows: the spray unit 130 injects cleaning fluid into the secondary ink tank 100, the ultrasonic transducer 140 causes the secondary ink tank 100 to vibrate for cleaning, and the wastewater after cleaning is discharged from the drain pipe 110.

[0098] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for ink supply circulation control, comprising the steps of: a first heater (200) in a secondary ink tank (100) heats ink in the secondary ink tank (100), and a suction stirring assembly (300) drives the ink in the secondary ink tank (100) to circulate; an ink supply pump (400) drives the ink in the secondary ink tank (100) to pass through a degassing damping assembly (500), a second heater (600) and a buffer portion (700) in sequence, a third heater (701) heats the ink in the buffer portion (700), and the ink in the buffer portion (700) can flow back to the secondary ink tank (100); a temperature T1 of the ink in the secondary ink tank (100) is obtained, a temperature T2 of the ink at an inlet of the buffer portion (700) is obtained, and a temperature T3 of the ink at an outlet of the buffer portion (700) is obtained; a first correspondence between ink viscosity and ink temperature is established in advance, and a second correspondence between ink viscosity and volume flow rate output by the ink supply pump (400) is established in advance Q ; According to the first correspondence relationship, the ink viscosity corresponding to the ink temperature T1 in the secondary ink barrel (100) is determined; according to the second correspondence relationship, the volumetric flow rate output by the ink supply pump (400) corresponding to the ink viscosity is determined Q The power of the first heater (200) remains unchanged, and the power P2 of the second heater (600) is calculated, and the calculation formula of P2 is: The heating power P3 of the third heater (701) is calculated, and the calculation formula of P3 is: ​ wherein, ρ is the ink density, c is the specific heat capacity of the ink, is the optimal temperature for ink printing, x has a value ranging from 1 to 4.

2. An ink supply circulation system for use in the ink supply circulation control method according to claim 1, characterized by comprising: a secondary ink tank (100) connected with a first heater (200) for heating ink in the secondary ink tank (100); a suction stirring assembly (300) for driving the ink in the secondary ink tank (100) to circulate; an ink supply pump (400) with an inlet connected with the secondary ink tank (100); a degassing damping assembly (500) connected with an outlet of the ink supply pump (400); a second heater (600) connected with the degassing damping assembly (500) for heating the ink flowing through the second heater (600); a buffer portion (700) with an inlet connected with the second heater (600) and an outlet connected with the secondary ink tank (100), the buffer portion (700) being connected with a third heater (701) for heating the ink in the buffer portion (700), the buffer portion (700) being used for receiving the ink from the second heater (600), and the ink in the buffer portion (700) being able to flow back to the secondary ink tank (100).

3. The ink circulation system of claim 2, wherein: An ink supply cavity (710) and an ink return cavity (720) are formed inside the buffer portion (700), the inlet of the buffer portion (700) is in communication with the ink supply cavity (710), the outlet of the buffer portion (700) is in communication with the ink return cavity (720), the ink supply cavity (710) is connected with a printhead inlet pipe (711), the ink return cavity (720) is connected with a printhead outlet pipe (721), a first pressure sensor (712) and a first temperature sensor (713) are arranged in the ink supply cavity (710), and a second pressure sensor (722) and a second temperature sensor (723) are arranged in the ink return cavity (720).

4. The ink circulation system of claim 3, wherein: A first turbulence portion (714) is arranged in the ink supply cavity (710), a second turbulence portion (724) is arranged in the ink return cavity (720), and the first turbulence portion (714) and the second turbulence portion (724) are used for reducing pressure fluctuation of the ink in the buffer portion (700).

5. The ink circulation system of claim 2, wherein: The buffer part (700) is connected with the secondary ink tank (100) through an ink return pipe (800), the ink return pipe (800) is provided with an ink return filter (810), a second damper (820) and an ink return pump (830), and the ink return pump (830) is used for conveying the ink in the ink return pipe (800) to the secondary ink tank (100).

6. The ink circulation system of claim 2, wherein: The ink supply pump (400) is connected with the secondary ink tank (100) through an ink supply pipe (410), the ink supply pipe (410) is connected with a vent pipe (420), the vent pipe (420) is communicated with the outside atmosphere through a vent filter (430), and a vent valve (440) is arranged between the vent filter (430) and the vent pipe (420).

7. The ink circulation system of claim 2, wherein: The degassing damping assembly (500) comprises a first damper (510) and a degassing tank (520), the first damper (510) receives the ink from the ink supply pump (400), the ink enters the degassing tank (520) after the pressure fluctuation is reduced through the first damper (510), and the gas in the ink is eliminated, and the degassing tank (520) is connected with a vacuum pump (530), and the vacuum pump (530) is used for pumping out the gas in the degassing tank (520).

8. The ink circulation system of claim 2, wherein: The suction stirring assembly (300) comprises an ink suction pipe (310), an ink supply pipe (320) and a stirring pump (330), the ink suction pipe (310) and the ink supply pipe (320) are connected with the secondary ink tank (100), the stirring pump (330) extracts the ink in the secondary ink tank (100) through the ink suction pipe (310) and conveys the ink into the secondary ink tank (100) through the ink supply pipe (320).

9. The ink circulation system of claim 2, wherein: The secondary ink tank (100) is connected with a drain pipe (110), the drain pipe (110) is provided with a drain valve (120), and the drain pipe (110) is used for discharging the ink in the secondary ink tank (100).

10. The ink circulation system of claim 2, wherein: The secondary ink tank (100) is connected with a spraying part (130) and an ultrasonic transducer (140), the spraying part (130) is installed on the inner top wall of the secondary ink tank (100), the spraying part (130) is used for injecting cleaning liquid into the secondary ink tank (100), and the ultrasonic transducer (140) is connected to the lower end of the secondary ink tank (100), and the ultrasonic transducer (140) can drive the secondary ink tank (100) to vibrate.

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