An ink color adjusting device, a printer, and a printing method

Abstract

The application discloses an ink color mixing device, a printer and a printing method. The ink color mixing device comprises an ink barrel assembly composed of multiple ink barrels (1), a peristaltic pump assembly composed of multiple first peristaltic pumps (2), an electromagnetic valve assembly composed of multiple first electromagnetic valves (3), a primary ink bottle assembly composed of multiple primary ink bottles (5), a mixing bottle (8), a secondary ink bottle (12) and a nozzle (13). Each ink barrel (1) in the ink barrel assembly is connected with a primary ink bottle (5) respectively. Each primary ink bottle (5) is connected with two first peristaltic pumps (2), a first electromagnetic valve (3) and a first liquid level float ball switch (6). One of the first peristaltic pumps (2) is used for ink input, and the other is used for ink output. The first liquid level float ball switch (6) is used for measuring the amount of ink in the primary ink bottle. The primary ink bottle (5) and its support are fixed on four force sensors (7).

Description

TECHNICAL FIELD

[0001] The present application belongs to a toning device, a printer and a printing method. BACKGROUND

[0002] Digital printing is a common printing process at present, which can realize high-efficiency industrial batch printing, has rich printing materials and is suitable for various customized commodities. Color printing is a printing method with larger application demand in digital printing. At present, a digital industrial printer is based on CMYK four-color ink or is provided with other auxiliary ink. The ink is sprayed from a nozzle to a printing material by digital control. Different colors of ink are mixed on the same point of the printing material according to certain proportions, so that the required color can be displayed. According to the principle of mixing and matching of multi-color ink, several specified colors of ink can be printed to realize various required colors.

[0003] When printing the color printing demand, the existing industrial printer usually needs multiple nozzles to spray different colors and volumes of ink droplets on the same point of the printing material to mix and form the required color, or a single nozzle realizes the specified color by multiple PASS back and forth printing, or increases multiple auxiliary color inks to realize the color printing at one time. The increase of ink color also requires an increase in the number of nozzles. In the face of expensive nozzles, this will increase the printing cost or reduce the printing efficiency, which will greatly increase the production cost.

[0004] The technical difficulty lies in that the combination of several specified colors of ink according to the fixed ink droplet volume of the selected nozzle is limited. At present, the number of nozzles, multiple PASS printing and auxiliary color inks are increased to increase the types of combined colors. Since the nozzles are expensive, the cost of the customer who needs color printing will be greatly increased. How to print the required color of the customer without increasing the cost and reducing the efficiency under the given ink needs to realize the arbitrary matching combination of ink during printing, so that the printed ink has a wider color gamut to meet the customer's demand for any color.

[0005] The existing printers on the market have the following shortcomings and problems:

[0006] 1. Color printing needs multiple nozzles to cooperate in ink spraying at the same point to print the required color, which increases the number of nozzles of the machine;

[0007] 2. The color gamut that can be printed is narrow. To print a wider color gamut, more auxiliary color inks need to be added, that is, the basic four-color ink CMYK is increased to six colors, eight colors, etc., which also means an increase in the number of nozzles;

[0008] 3. In the same nozzle, often need to pass through a variety of color ink, in the nozzle cleaning ink scraping, moisturizing, easy to appear ink color problem;

[0009] 4. When printing, the demand for part of the color ink is small for a single nozzle, and the same number of ink ejection holes are occupied, the use intensity of each ink ejection hole is different, and resource waste caused by part of the ink ejection holes reaching the service life and being scrapped is easy to occur. SUMMARY

[0010] The technical problem to be solved by the present application is to provide a pure color ink color mixing device and a color mixing method to overcome the shortcomings of the prior art.

[0011] The technical solution adopted by the present application to solve the above technical problems is as follows:

[0012] An ink color mixing device, comprising: an ink barrel assembly composed of a plurality of ink barrels (1); a peristaltic pump assembly composed of a plurality of first peristaltic pumps (2); an electromagnetic valve assembly composed of a plurality of first electromagnetic valves (3); a first-stage ink bottle assembly composed of a plurality of first-stage ink bottles (5); a mixing bottle (8), a second-stage ink bottle (12), and a nozzle (13), wherein each ink barrel (1) in the ink barrel assembly is connected with a first-stage ink bottle (5) respectively; each first-stage ink bottle (5) is connected with two first peristaltic pumps (2), a first electromagnetic valve (3), and a first liquid level float ball switch (6), one of the first peristaltic pumps (2) is used for ink inlet and the other is used for ink outlet, the first liquid level float ball switch (6) is used for measuring the amount of ink in the first-stage ink bottle, the first-stage ink bottle (5) and its support are fixed on four force sensors (7), the signals of the sensors (7) can individually sense the weight change of the first-stage ink bottle assembly, so as to realize accurate control of the outflowing ink; the ink pumped out by the plurality of first-stage ink bottles (5) is connected to the second electromagnetic valve (31) above the interface of the mixing bottle (8) through an ink pipe (4), so as to realize mixing of the ink in the mixing bottle into the color required for fixed color printing; the mixing bottle (8) has a second liquid level float ball switch (61) and a stirring rod assembly (9), the stirring rod assembly (9) is used for uniformly mixing the ink, and the second liquid level float ball switch (61) is used for measuring the volume of the ink in the mixing bottle and controlling whether the ink needs to be added to the mixing bottle.

[0013] A printer comprising the above-mentioned ink color mixing device.

[0014] A printing method of the above-mentioned printer, comprising the following steps:

[0015] Step 1) According to the color requirement of the analyzed printing pattern, the ink of the appropriate color is matched;

[0016] Step 2) the pattern to be printed is parsed by color management software to obtain the proportion of each color ink, and according to the proportion of each color ink, the first peristaltic pump under the first ink bottle is controlled to flow out the corresponding volume of ink into the mixing bottle in sequence, and the mixing bottle is opened to stir the ink uniformly;

[0017] Step 3) the ink stirred uniformly in the mixing bottle flows into the second ink bottle on the trolley, and is connected to the nozzle for pure color printing.

[0018] After the above scheme is adopted, only color adjustment of the printer before printing is needed, and only one nozzle is needed to print one pass to complete the task. Compared with the conventional ink path, the efficiency can be improved by 4 times, or the number of nozzles can be reduced to 25% of the conventional ink path. In this way, the efficiency can be improved and the cost of the printer can be reduced.

[0019] Other features and advantages of the present application will be set forth in the following description, and in part will become apparent to those skilled in the art from the description, or can be learned by practice of the present application. The objects and other advantages of the present application can be achieved and obtained by the structure particularly pointed out in the written description and the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0020] The present application will be described in detail below with reference to the accompanying drawings, so that the above advantages of the present application are more apparent. Among them,

[0021] Figure 1 is a structural schematic view of the ink color mixing device of the present application;

[0022] Figure 2 is a structural connection schematic view of the ink color mixing device of the present application;

[0023] Figure 3 is a structural schematic view of the ink color mixing device of the present application;

[0024] Figure 4 is a structural schematic view of the ink color mixing device of the present application;

[0025] Figure 5 is a structural schematic view of the ink color mixing device of the present application;

[0026] Figure 6 is a structural schematic view of the ink color mixing device of the present application. DETAILED DESCRIPTION

[0027] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings and examples, so that the process of how the present invention uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that, as long as there is no conflict, the various embodiments and features in the various embodiments of the present invention can be combined with each other, and the resulting technical solutions are all within the protection scope of the present invention.

[0028] Specifically, such as Figure 1 As shown, a printer includes an ink mixing device, comprising: an ink tank assembly consisting of multiple ink tanks (1); a peristaltic pump assembly consisting of multiple first peristaltic pumps (2); a solenoid valve assembly consisting of multiple first solenoid valves (3); a primary ink bottle assembly consisting of multiple primary ink bottles (5); a mixing bottle (8), a secondary ink bottle (12), and a printhead (13), wherein each ink tank (1) in the ink tank assembly is connected to a primary ink bottle (5); each primary ink bottle (5) is connected to two first peristaltic pumps (2), a first solenoid valve (3), and a first liquid level float switch (6), wherein one of the first peristaltic pumps (2) is for ink inlet and the other for ink outlet, and the first liquid level float switch (6) is used to measure the ink level. The ink volume in the primary ink bottle is measured by the fact that the primary ink bottle (5) and its support are fixed on four force sensors (7). The signals of the sensors (7) can individually sense the weight change of the primary ink bottle assembly, thereby achieving precise control of the outflowing ink. The ink pumped out by multiple primary ink bottles (5) is connected to the second solenoid valve (31) above the interface of the mixing bottle (8) through the ink tube (4), so that the ink is mixed in the mixing bottle to form the color required for color printing. The mixing bottle (8) contains a second liquid level float switch (61) and a stirring rod assembly (9). The stirring rod assembly (9) is used to mix the ink evenly, and the second liquid level float switch (61) is used to measure the volume of ink in the mixing bottle and control whether more ink needs to be added to the mixing bottle.

[0029] The mixing bottle (8) is also connected to a second peristaltic pump (21), which supplies ink to the secondary ink bottle (12). A third liquid level float switch (62) is provided in the secondary ink bottle (12). The third liquid level float switch (62) is used to measure its ink content and control whether the second peristaltic pump (21) continues to supply ink. A third solenoid valve (32) is provided in front of the second peristaltic pump (21). The secondary ink bottle (12) is connected to the printhead (13) so that each printhead (13) sprays only one color of ink required for solid color printing.

[0030] The upper part of the mixing bottle (8) is also connected with a cleaning peristaltic pump (10), the cleaning peristaltic pump (10) is connected with a cleaning liquid bottle (11) in turn, and a quantitative cleaning liquid can be pumped into the mixing bottle; the front of the cleaning peristaltic pump (10) is also provided with a three-way third electromagnetic valve (not shown) connected and injected with distilled water, so as to realize the cleaning of the ink path from the mixing bottle (8) to the nozzle.

[0031] In the preferred embodiment, four separate ink barrels are arranged in the ink barrel assembly, and the ink barrel assembly is filled with basic CMYK four-color ink through the four ink barrels.

[0032] The printing method of the printer comprises the following steps:

[0033] Step 1: design a real-time quantitative mixing device of fixed-color ink, automatically match the ink of appropriate color according to the color demand of the analyzed printing pattern;

[0034] Step 2: four ink barrels are filled with basic CMYK four-color ink, and each ink barrel is connected with a first-level ink bottle, and the first-level ink bottle is located above a precise force sensor, so that the inflow and outflow of the ink in each first-level ink bottle can be accurately measured;

[0035] Step 3: the pattern to be printed is analyzed by color management software to obtain the matching of each color ink, and according to the matching of each color ink, the peristaltic pump below the first-level ink bottle is controlled to flow out the corresponding volume of ink into the mixing bottle in turn, and the mixing bottle is opened to stir the ink uniformly;

[0036] Step 4: the uniformly stirred ink in the mixing bottle flows into the second-level ink bottle on the trolley, and then is connected to the nozzle to perform pure color printing;

[0037] Step 5: during the long-term printing process, the color of the ink is calibrated once every time the paper is replaced, so as to ensure the color consistency of the early and late stages of the printing process;

[0038] Step 6: after the required fixed-color printing is completed, when other color fixed-color printing needs to be replaced, the cleaning pump is opened to add ink cleaning liquid and cleaning water to the mixing bottle, and the peristaltic pump of the mixing bottle is used to clean the ink path from the mixing bottle to the nozzle, and after the cleaning is completed, other pure color printing can be performed;

[0039] Specifically, four ink tanks are taken as the basis, and the four ink tanks correspond to four first-level ink bottles, each first-level ink bottle corresponds to two peristaltic pumps, solenoid valves and a liquid level float switch, one peristaltic pump is used for ink input and the other is used for ink output, and the liquid level float switch is used to measure the amount of ink in the first-level ink bottle; the first-level ink bottle and its bracket are fixed on four force sensors, and the weight change of the first-level ink bottle assembly can be accurately perceived through the sensor signal, so as to realize accurate control of the outflowing ink; the ink pumped out by the four first-level ink bottles is connected to the electromagnetic valve above the mixing bottle interface through the ink pipe, so as to realize the mixing of the ink in the mixing bottle into the color required for color printing; the mixing bottle has a liquid level float switch and a stirring rod assembly, which are used to uniformly mix the ink and measure the volume of the ink in the mixing bottle to control whether the ink needs to be added to the mixing bottle; a cleaning peristaltic pump is connected above the mixing bottle, which can pump a certain amount of cleaning fluid and distilled water into the mixing bottle during the ink path cleaning stage, so as to realize the cleaning of the ink path from the mixing bottle to the nozzle; the mixing bottle supplies ink to the second-level ink bottle through the peristaltic pump, and the liquid level float switch in the second-level ink bottle measures the ink content to control whether the peristaltic pump continues to supply ink; the second-level ink bottle is connected with the nozzle, so that each nozzle can only spray one color of ink required for color printing, so that each nozzle can work at maximum efficiency, thereby reducing the cost and improving the efficiency.

[0040] Wherein, before printing, the required color pattern is analyzed by using RIP software to obtain the RGB value of the pattern, and according to the conversion relationship between RGB and CMYK:

[0041] K = 1-max(R / 255, G / 255, B / 255)

[0042] C = (1-R / 255-K) / (1-K)

[0043] M = (1-G / 255-K) / (1-K)

[0044] Y = (1-B / 255-K) / (1-K)

[0045] Wherein, 0≤(K, C, M, Y)≤1.

[0046] The above formula can calculate the proportion relationship of the CMYK ink required for color printing.

[0047] The ink cartridges are respectively filled with CMYK four-color inks, and the density of the ink used for printing needs to be measured first, and the measured ink density (unit: g / mL) is respectively ρ1, ρ2, ρ3, and ρ4. After the printer is turned on, the ink supply pumps of the four primary ink bottles are turned on, the electromagnetic valve of the ink outlet of the primary ink bottle is turned off, the ink is extracted from the ink cartridge into the primary ink bottle, and the ink level is detected by the ink level float switch. When the ink level is detected, the corresponding peristaltic pump is turned off. After the ink supply peristaltic pumps of the four primary ink bottles are stopped, the force sensor below the primary ink bottle assembly is set to the initial 0 value.

[0048] At this time, the ink path from the ink outlet of the primary ink bottle to the ink supply end of the mixing bottle is empty, the electromagnetic valve and peristaltic pump 5 of the K color primary ink bottle ink outlet are turned on first, when the ink flows along the ink path to the mixing bottle inlet, the electromagnetic valve at the mixing bottle inlet is disconnected after sensing the ink, the electromagnetic valve and peristaltic pump of the K color primary ink bottle ink outlet are also disconnected, that is, the ink path from the ink outlet of the primary ink bottle to the ink supply end of the mixing bottle is supplemented, and then the K color primary ink bottle ink supply electromagnetic valve and peristaltic pump 1 are turned on. The K color primary ink bottle is supplemented to the force sensor value to restore to 0. The ink of the remaining three colors is supplemented in the same way. Among them, the electromagnetic valve at the ink supply end of the mixing bottle is water-controlled and electrically controlled, and the electric control priority is higher than the water control, which is used to supplement the ink in the empty section of the ink path during the initial ink filling.

[0049] The total volume of the ink to be mixed in the mixing bottle at one time is set as V0 (unit: mL), and according to the CMYK values calculated by the software, the volumes (unit: mL) of the four colors of ink to be added to the mixing bottle are respectively:

[0050]

[0051] The mass (unit: g) of the corresponding ink is:

[0052] m1=V1ρ1,m2=V2ρ2,m3=V3ρ3,m4=V4ρ4

[0053] The four ink outlet peristaltic pumps corresponding to the four primary ink bottles have a proportional relationship between the flow rate of the peristaltic pump at a fixed speed and a very strong stability, and the corresponding relationship between the rotational speed n (unit: r / min) of the four peristaltic pumps and the flow rate Q (unit: mL / min) thereof can be measured as:

[0054] Q=k0n

[0055] Wherein, the flow rate of the peristaltic pump is proportional to its rotational speed, and k0 is the proportional coefficient, which needs to be measured by the selected peristaltic pump, and the approximate relationship is

[0056]

[0057] Wherein, d is the inner diameter of the ink tube in the peristaltic pump, D is the diameter of the peristaltic pump runner, since the ink tube part position is compressed by the runner in practice, the actual flow is smaller than the flow in the above formula, but the proportional relationship is unchanged.

[0058] For the first ink bottle ink supply and ink output, we take the precision force sensor reading at the bottom as the reference, and the flow data of the ink supply peristaltic pump and the ink output peristaltic pump as auxiliary. The flow data of the peristaltic pump should be within 1% error of the force sensor reading in a short time, and within 0.5% error in a long time. When the flow data of the peristaltic pump and the mass data of the force sensor deviate greatly, an alarm will be prompted to check the structure of the peristaltic pump and the force sensor to ensure the accuracy of the ink supply data.

[0059] Therefore, we set two rotation speeds (unit: r / min) for the ink output peristaltic pump of the first ink bottle: high speed n1 and low speed n2. The high speed n1 is used for the first ink bottle to supply ink to the mixing bottle quickly, and when the ink supply of the mixing bottle is slightly lower than the required amount, the low speed n2 is switched to slowly adjust, so that the required amount of ink in the mixing bottle is accurate enough.

[0060] The ink is supplied from the first ink bottle to the mixing bottle in the order of CMYK. The electromagnetic valve, peristaltic pump, and electromagnetic valve at the ink supply end of the mixing bottle are opened. Since the required amount of K color ink is V1, the ink output peristaltic pump 5 of the first ink bottle 1 is first opened at high speed n1 for time t1 (unit: s), where t1 satisfies If t1 = 0

[0061] At this time, the mass of the first ink bottle assembly will decrease, and the force sensor below it can read the mass flowing into the mixing bottle at this time. When the force sensor reading is equal to the required mass m1 at low speed n2, the ink output peristaltic pump is stopped, and the K color ink is quantitatively flowed into the mixing bottle at this time. The other three colors of ink are also flowed into the mixing bottle according to the above method to the specified volume of ink. When the ink supply to the mixing bottle is completed, the mass reading of the force sensor should be m1+m2+m3+m4.

[0062] The motor of the stirring rod assembly is started, and the stirring rod rotates in the mixing bottle to drive the ink to mix uniformly, so that the required pure color ink can be realized.

[0063] At the same time, since part of the ink of the first ink bottle assembly is lost, the ink supply peristaltic pump needs to be started for ink replenishment until the force sensor reading returns to the initial value 0. First, start the ink supply peristaltic pump 1 of the K color first ink bottle, supply ink at high speed n1 for time t1, and then change to low speed n2 for slow ink supply. When the force sensor reading decreases by m1, that is, becomes m2+m3+m4, stop the ink supply peristaltic pump. The first ink bottles of the other three inks are also replenished according to the above method, and the force sensor reading is stopped when it is 0.

[0064] After the ink in the mixing bottle is evenly mixed, the stirring rod motor is turned off, at this time the ink supply pump of the mixing bottle to the secondary ink bottle is turned on, the pure color ink is pressed to the secondary ink bottle, until the liquid level float switch of the secondary ink bottle responds to stop the ink supply, at this time the secondary ink bottle can directly supply pure color ink to the printhead to print, realizing that each printhead prints the same color ink, improving the utilization rate of the printhead and reducing the printing cost.

[0065] During printing, if the ink in the secondary ink bottle is lower than the liquid level float switch, the ink supply pump of the mixing bottle is started to supply ink to the secondary ink bottle, until the ink in the secondary ink bottle reaches the position of the liquid level float switch to stop the ink supply, then the peristaltic pump of the primary ink bottle is started to add m1, m2, m3, m4 mass of ink to the mixing bottle, the mixing bottle is stirred to mix the ink evenly, and finally the ink supply pump of the primary ink bottle is turned on to supplement m1, m2, m3, m4 mass of ink from the ink tank to the primary ink bottle, at this time the ink supply of the entire ink path is completed.

[0066] During continuous printing, each ink supply needs to extract m1, m2, m3, m4 mass of ink, that is, V1, V2, V3, V4 volume of ink from the CMYK ink tank, after a time t (unit: min), the software records the number of times a of ink extraction in the ink tank, the total number of Pass b of printing, and then the ink consumption per Pass (unit: mL) of CMYK four-color ink can be estimated.

[0067]

[0068] The initial ink amount in the ink tank is V0 (unit: mL), the available time (unit: min) and the remaining ink amount (unit: mL) of CMYK remaining ink can be calculated.

[0069] V k0 = V0-aV1, V c0 = V0-aV2, V m0 = V0-aV3, V y0 = V0-aV4

[0070]

[0071] In this way, the remaining amount of each color ink and the continuous printing time can be clearly displayed, when the remaining ink in the ink tank is less than 500 mL, the printer can issue a warning prompt to supplement the corresponding color ink, realizing stable control of the remaining ink amount, improving production efficiency and reducing unnecessary ink changing time.

[0072] When another color printing is needed after a color printing is completed, open the cleaning peristaltic pump, add a certain amount of cleaning liquid to the mixing bottle, switch the three-way electromagnetic valve before the cleaning peristaltic pump to connect to distilled water, and then add a certain amount of distilled water to the mixing bottle. In this way, the ink path from the mixing bottle to the nozzle can be cleaned multiple times until the ink path is clean.

[0073] Taking EPSON-i3200-A1 nozzle printing as an example, the number of nozzles required and the printing efficiency under the conventional ink path are compared with the number of nozzles required and the printing efficiency of the pure color toning device ink path of the present scheme.

[0074] For example, when printing a color with RGB value (148, 212, 43), the KCMY value

[0075] K = 1 - max(125 / 255, 212 / 255, 43 / 255) ≈ 0.17

[0076] C = (1-148 / 255-0.17) / (1-0.17) ≈ 0.30

[0077] M = (1-212 / 255-0.17) / (1-0.17) ≈ 0

[0078] Y = (1-43 / 255-0.17) / (1-0.17) ≈ 0.80

[0079] The ratio of the four colors is approximately K:C:M:Y = 1:1.8:0:4.7, where the theoretical value of M is 0, but due to differences in ink, printer, and substrate, etc. will bring about slight differences in color, and color management software is needed to fine-tune the color. The ratio during actual printing is based on the adjustment results of the machine before printing. Here we analyze the variation law based on the theoretical value.

[0080] Under the conventional ink path, the size of the ink droplets that can be sprayed by the nozzle during multi-point printing is 3.8pL, 6pL, and 12pL, respectively. Using each nozzle at 600dpi to print four colors of ink, according to the three ink droplet volumes that can be sprayed by the EPSON-i3200-A1 nozzle, the number of ink droplets required to achieve the KCMY ratio is calculated as follows:

[0081] Small droplet 3.8 pL Medium droplet 6 pL Large droplet 12 pL Ratio of droplet volumes K 2 0 0 0.17 C 2 1 0 0.30 M 0 0 0 0 Y 0 2 2 0.81

[0082] The above results show that the ratio of Y color is slightly different from the theoretical value, and Y color needs to be printed the most times. A total of 4 points are needed, that is, if the current color is printed with 1Pass, 4 nozzles are needed, if it is printed with 2Pass, 2 nozzles are needed, and if it is printed with 4Pass, 1 nozzle is needed.

[0083] The ink path of the present solution only needs to complete the color adjustment of the printer before printing, and only one nozzle is needed to print one pass to complete the task. Compared with the conventional ink path, the efficiency can be improved by 4 times, or the number of nozzles can be reduced to 25% of the conventional ink path. In this way, the efficiency can be improved and the cost of the printer can be reduced.

[0084] In actual production printing, in order to reduce the influence of ink color at the beginning and end of printing, color verification is needed once every time a roll of paper is replaced, and the verification result is updated to the KCMY ink ratio, so as to maintain the consistency of the ink color during long-term printing.

[0085] It should be noted that, for the above method embodiments, in order to simply describe, they are all expressed as a series of action combinations, but those skilled in the art should know that the present application is not limited by the action sequence described, because according to the present application, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should know that the embodiments described in the specification all belong to preferred embodiments, and the actions and modules involved are not necessarily necessary for the present application.

[0086] Finally, it should be pointed out that: the above only describes the preferred embodiments of the present application, and is not used to limit the present application, although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. An ink mixing device, characterized in that, include: An ink tank assembly consisting of multiple ink tanks (1); a peristaltic pump assembly consisting of multiple first peristaltic pumps (2); a solenoid valve assembly consisting of multiple first solenoid valves (3); a first-stage ink bottle assembly consisting of multiple first-stage ink bottles (5); a mixing bottle (8), a second-stage ink bottle (12), and a printhead (13), wherein, In the ink tank assembly, each ink tank (1) is connected to a primary ink bottle (5); each primary ink bottle (5) is connected to two first peristaltic pumps (2), a first solenoid valve (3) and a first liquid level float switch (6). One of the first peristaltic pumps (2) is for ink inlet and the other is for ink outlet. The first liquid level float switch (6) is used to measure the amount of ink in the primary ink bottle. The primary ink bottle (5) and its support are fixed on four force sensors (7). The signals of the sensors (7) can individually sense the weight change of the primary ink bottle assembly, thereby achieving precise control of the outflowing ink. The ink pumped out by multiple primary ink bottles (5) is connected to the second solenoid valve (31) above the interface of the mixing bottle (8) through the ink tube (4), so that the ink is mixed in the mixing bottle to form the color required for color fixing printing; The mixing bottle (8) contains a second liquid level float switch (61) and a stirring rod assembly (9); The stirring rod assembly (9) is used to uniformly mix the ink. The second liquid level float switch (61) is used to measure the volume of ink in the mixing bottle and control whether more ink needs to be added to the mixing bottle. The mixing bottle (8) is also connected to a second peristaltic pump (21) and supplies ink to the secondary ink bottle (12) through the second peristaltic pump (21). A third liquid level float switch (62) is installed in the secondary ink bottle (12). The third liquid level float switch (62) is used to measure its ink content and control whether the second peristaltic pump (21) is activated. Continue to supply ink. The secondary ink bottle (12) is connected to the printhead (13) so that each printhead (13) sprays only one color of ink required for solid color printing. A cleaning peristaltic pump (10) is also connected above the mixing bottle (8). The cleaning peristaltic pump (10) is connected to a cleaning liquid bottle (11) so that a certain amount of cleaning liquid can be pumped into the mixing bottle. A three-way third solenoid valve (32) is also provided in front of the cleaning peristaltic pump (10) to connect and inject distilled water to realize the ink path cleaning from the mixing bottle (8) to the printhead.

2. A printer, characterized in that, Includes the ink mixing device as described in claim 1.

3. A printing method based on the printer of claim 2, characterized in that, include: Step 1) Based on the color requirements of the printed pattern, mix the appropriate color ink; Step 2) The pattern to be printed is analyzed by the color management software to determine the ratio of each color ink. According to the ratio of each color ink, the first peristaltic pump under the first ink bottle is controlled to flow the corresponding volume of ink into the mixing bottle in sequence. The mixing bottle is turned on to stir the ink evenly. Step 3) The ink, which has been thoroughly stirred in the mixing bottle, flows into the secondary ink bottle on the carriage, and can then be connected to the printhead for solid color printing; Before step 1), the process also includes: using RIP software to analyze the solid color pattern to be printed, obtaining the RGB values ​​of the pattern, and based on the conversion relationship between RGB and CMYK: K = 1 - max(R / 255, G / 255, B / 255) C = (1 - R / 255 - K) / (1 - K) M = (1 - G / 255 - K) / (1 - K) Y = (1 - B / 255 - K) / (1 - K) Where 0≤(K,C,M,Y)≤1; The CMYK ink ratio required for printing solid color patterns was calculated. Step 1) specifically includes: Measure the density of the ink used for printing, and let the measured ink densities be ρ1, ρ2, ρ3, and ρ4. After the printer is turned on, the first peristaltic pump corresponding to the four primary ink bottles is turned on, the first solenoid valve of the ink outlet of the primary ink bottle is turned off, and ink is drawn from the ink tank into the primary ink bottle until the liquid level float switch of the primary ink bottle detects the ink level and turns off the corresponding first peristaltic pump. After the peristaltic pumps supplying ink to the four primary ink bottles have stopped, the force sensor below the primary ink bottle assembly is set to the initial value of 0. The ink path from the ink outlet of the primary ink bottle to the ink supply of the mixing bottle is empty. First, open the solenoid valve and peristaltic pump at the ink outlet of the K-color primary ink bottle. When the ink reaches the inlet of the mixing bottle along the ink path, the solenoid valve at the inlet of the mixing bottle senses the ink and disconnects. The solenoid valve and peristaltic pump at the ink outlet of the K-color primary ink bottle also disconnect, thus completing the ink path replenishment from the ink outlet of the primary ink bottle to the ink supply of the mixing bottle. Then, the ink supply solenoid valve and peristaltic pump 1 of the K-color primary ink bottle are opened to replenish the K-color primary ink bottle until the force sensor value returns to 0. Replenish the remaining ink in the three ink paths using the same method. The solenoid valve at the ink supply end of the mixing bottle is both water-controlled and electric-controlled, with the electric control having higher priority than the water control. Its function is to replenish the ink in the empty ink path during the initial ink filling. Let V0 be the total volume of ink to be mixed in the mixing bottle at one time. Based on the CMYK values ​​calculated by the software, the volumes of the four colors of ink to be added to the mixing bottle are as follows: The corresponding ink mass (unit: g) is m1=V1ρ1, m2=V2ρ2, m3=V3ρ3, m4=V4ρ4 Four peristaltic pumps corresponding to four primary ink bottles were used to measure the relationship between the rotational speed n of these four peristaltic pumps and their flow rate Q. The relationship was found to be: Q = k0n, where... The flow rate of a peristaltic pump is directly proportional to its rotational speed, where k0 is the proportionality coefficient. This coefficient needs to be determined by actual measurements of the selected peristaltic pump. An approximate relationship is as follows: Where d is the inner diameter of the ink tube in the peristaltic pump, and D is the diameter of the peristaltic pump impeller. Since part of the ink tube is compressed by the impeller in reality, the actual flow rate is smaller than the flow rate in the above formula, but the proportional relationship remains unchanged. For the ink supply and output of the primary ink bottle, the reading of the precision force sensor at its bottom is the standard, and the flow data of the ink supply peristaltic pump and the ink output peristaltic pump are the auxiliary. The flow data of the peristaltic pump should have an error of less than 1% with the force sensor reading in a short time and an error of less than 0.5% in a long time. When there is a significant deviation between the peristaltic pump flow rate data and the force sensor quality data, an alarm will be triggered, indicating that the structure of the peristaltic pump and force sensor needs to be checked to ensure the accuracy of the ink supply data.

4. The printing method according to claim 3, characterized in that, Also includes: Before changing to other colors for printing, turn on the cleaning peristaltic pump (10), add ink cleaning solution and cleaning water to the mixing bottle, and use the cleaning peristaltic pump (10) of the mixing bottle to clean the ink path from the mixing bottle to the printhead. After cleaning, you can print other solid colors. During long-term printing, the ink color is calibrated every time the paper roll is changed to ensure color consistency in the early and later stages of the printing process.

5. The printing method according to claim 3, characterized in that, Also includes: Two speeds are set for the peristaltic pump of the primary ink bottle: high speed n1 and low speed n2. High speed n1 is used to quickly supply ink from the primary ink bottle to the mixing bottle. When the ink supply to the mixing bottle is slightly lower than the required amount, it is switched to low speed n2 to slowly adjust so that the required amount of ink in the mixing bottle is accurate enough. Ink is supplied sequentially from the primary ink bottle to the mixing bottle in the order of CMYK. The solenoid valves at the ink outlets of the primary ink bottles, the peristaltic pump, and the solenoid valve at the ink supply end of the mixing bottle are opened. Since the demand for K-color ink is V1, the peristaltic pump 5 of the primary ink bottle 1 is first opened at high speed n1 for time t1, where t1 satisfies: like Then take t1 = 0 At this time, the mass of the first ink bottle assembly will decrease, and the force sensor below it can read the mass flowing into the mixing bottle at this time. Under low ink output speed n2, when the reading of the force sensor is equal to the required mass m1, the ink output peristaltic pump can be stopped. At this time, ink K is quantitatively flowing into the mixing bottle. The other three colors of ink flow into the mixing bottle in the same way as above, with a specified volume of ink. After the ink supply to the mixing bottle is completed, the mass reading of the force sensor should be m1+m2+m3+m4. Start the motor of the stirring rod assembly. The stirring rod rotates fully in the mixing bottle, causing the ink to mix evenly, thus achieving the desired pure color ink.

6. The printing method according to claim 3, characterized in that, Also includes: Start the ink supply peristaltic pump to replenish ink until the force sensor reading returns to its initial value of 0; First, start the peristaltic pump 1 for supplying ink to the K-color primary ink bottle, press the high speed n1 for ink supply time t1, then switch to the low speed n2 for slow ink supply. When the force sensor reading decreases by m1, that is, becomes m2+m3+m4, stop the peristaltic pump 1. Replenish the primary ink bottles of the other three types of ink in the same way, and stop when the force sensor reading is 0. After the ink in the mixing bottle is evenly mixed, the stirring rod motor is disconnected. At this time, the ink supply pump from the mixing bottle to the secondary ink bottle is turned on, and the pure color ink is pumped into the secondary ink bottle until the liquid level float switch of the secondary ink bottle responds and stops the ink supply. At this time, the secondary ink bottle can directly supply pure color ink to the printhead for printing, so that each printhead prints the same required color of ink.

7. The printing method according to claim 6, characterized in that, Also includes: If the ink level in the secondary ink bottle is lower than the level float switch, start the ink supply pump of the mixing bottle to supply ink to the secondary ink bottle until the ink level in the secondary ink bottle reaches the level float switch position, then stop supplying ink. Next, start the peristaltic pump of the primary ink bottle to add ink of mass m1, m2, m3, and m4 to the mixing bottle. The mixing bottle stirs to mix the ink evenly. Finally, start the ink supply pump of the last ink bottle to replenish ink of mass m1, m2, m3, and m4 from the ink tank to the primary ink bottle. At this point, the ink replenishment of the entire ink circuit is completed.

8. The printing method according to claim 3, characterized in that, Also includes: During continuous printing, each ink refill requires drawing ink from the CMYK ink tank by masses m1, m2, m3, and m4, which are equivalent to volumes V1, V2, V3, and V4, respectively. After time t, the software records the number of ink draws a from the ink tank and the total number of print passes b. This allows for an estimation of the ink consumption per pass for the four CMYK inks. The initial ink level in the ink tank is V0. The usable time and remaining ink level of the remaining CMYK ink can be calculated. V k0 =V0-aV1,V c0 =V0-aV2,V m0 =V0-aV3,V y0 =V0-aV4 This allows for clear control of the remaining ink levels for each color and the duration of continuous printing. When the ink level in the ink tank is less than 500mL, the printer can issue a warning indicating that the corresponding color ink needs to be replenished, thus achieving stable control over the remaining ink levels, improving production efficiency, and reducing unnecessary ink change time.

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