WO2023029068A1

WO2023029068A1 - Ink supply system for ceramic ink printing

Info

Publication number: WO2023029068A1
Application number: PCT/CN2021/117375
Authority: WO
Inventors: 夏俊; 唐文来
Original assignee: 南京智能高端装备产业研究院有限公司
Priority date: 2021-09-06
Filing date: 2021-09-09
Publication date: 2023-03-09
Also published as: CN113635674B; CN113635674A

Abstract

The present invention provides an ink supply system for ceramic ink printing. The system comprises: an ink circulating supply module, a control module, a software module and a negative-pressure cleaning module, wherein the ink circulating supply module is used for forming a negative-pressure printing environment, and implementing ceramic ink printing and ink circulating supply after receiving a control command and a control parameter from the software module; sensors in the ink circulating supply module can acquire the data and state of the ink supply system, and send same to the control module; the control module receives the data and state of the ink supply system, and then returns same to the software module, and receives the control command and the control parameter that are sent by the software module, and then transmits same to modules of the system, so as to control collaborative operation of the modules; and the negative-pressure cleaning module cleans a ceramic ink piezoelectric printing head assembly. By means of the present invention, the performance of an industrial nozzle in terms of printing with high-sedimentation ink is improved, and the risk of nozzle holes being blocked is reduced to the greatest extent, such that the service life of the industrial nozzle is prolonged, thereby improving economic benefits.

Description

An ink supply system for ceramic ink printing

technical field

The invention relates to the technical field of ink printing, in particular to an ink supply system for ceramic ink printing.

Background technique

In the field of ink printing technology, all industrial piezoelectric nozzles need to provide a stable negative pressure to resist the surface tension of the ink and natural gravity. At present, there are generally two ways to generate negative pressure: natural siphon and air negative pressure. The principle of natural siphon is generally only suitable for water-based inks with low viscosity, not for ceramic inks with high viscosity and high sedimentation characteristics; air negative pressure is suitable for many inks. However, its negative pressure control accuracy is poor, and the negative pressure control process has large jitters, which leads to unbalanced negative pressure and affects the final inkjet quality. In addition, since ceramic ink is a high-sedimentation ink, it is prone to problems of precipitation and nozzle clogging during the printing process.

Therefore, there is an urgent need for an ink supply system that can be used for ceramic ink printing, and can achieve stable printing and avoid problems of sedimentation and clogging.

Contents of the invention

The invention provides an ink supply system for ceramic ink printing to solve the problems that the existing ink printing device is not suitable for ceramic ink printing, resulting in unstable printing, and precipitation and blockage during the printing process.

An ink supply system for ceramic ink printing provided by the present invention includes: a circulating ink supply module, a control module, a software module and a negative pressure cleaning module;

The circulating ink supply module includes a circulating ink outlet pipeline, a ceramic ink piezoelectric print head assembly and an ink return pipeline for forming a negative pressure printing environment, and after receiving the control command and control parameters of the software module , to realize ceramic ink printing and ink circulation; the ink circulation module also includes a sensor for acquiring the data and status of the ink supply system and sending them to the control module;

The control module is used to receive the data and status of the ink supply system, and return to the software module, after receiving the control command and control parameters sent by the software module, transmit them to each of the ink supply system module, controlling the cooperative operation of each module;

The software module is used to analyze the data and status of the ink supply system, and send control commands and control parameters to the control module according to the analysis results;

The negative pressure cleaning module is used for cleaning the ceramic ink piezoelectric print head assembly.

Further, in an implementation manner, the ink outlet pipeline includes a secondary ceramic ink container, a three-way solenoid valve, an ink outlet diaphragm pump, an ink outlet damper, a filter and a drainage valve, and a secondary ceramic ink container that is sequentially connected through an opaque ink tube. Gas device and temperature-controlled heater;

The secondary ceramic ink container is provided with an ink outlet connected to the three-way solenoid valve, and an ink return port connected to the ink return pipeline, which are respectively used to provide and collect ceramic ink;

The three-way solenoid valve determines the working state according to the control command and control parameters sent by the control module. When the three-way solenoid valve determines that the working state is the ink supply state, one end of the three-way solenoid valve communicates with the ink outlet, and the other end of the three-way solenoid valve communicates with the ink outlet. One end communicates with the ink outlet diaphragm pump, and the three-way solenoid valve cooperates with the ink outlet diaphragm pump to extract the ceramic ink in the secondary ceramic ink container from the ink outlet;

One end of the ink outlet damper communicates with the ink outlet diaphragm pump, and the other end communicates with the filter and exhaust device, which is used to remove the pressure pulse generated when the ink outlet diaphragm pump works, and reduce the flow rate fluctuation of the ceramic ink;

One end of the filter and exhaust device communicates with the ink outlet damper, and the other end communicates with the temperature-controlled heater for heating the ceramic ink filtered by the filter and exhaust device. There is also a drain hole and an ink tube communicating with the drain hole, the other end of the ink tube communicates with the secondary ceramic ink container for collecting the air in the ceramic ink and the atomized ink to the secondary ceramic ink container;

One end of the temperature-controlled heater communicates with the filter and exhaust device, and the other end communicates with the ceramic ink piezoelectric print head assembly, for providing filtered and heated ceramic ink to the ceramic ink piezoelectric print head assembly.

Further, in an implementation manner, the ink outlet pipeline also includes an air filter; when the three-way solenoid valve determines that the working state is the cleaning state according to the control command and control parameters sent by the control module, the three-way solenoid valve The opaque ink tube between the solenoid valve and the ink outlet is disconnected, the air filter communicates with the three-way solenoid valve, and the air filter pumps clean air into the ink supply system through the three-way solenoid valve, To clean all the pipelines in the ink supply system.

Further, in an implementation manner, the ceramic ink piezoelectric print head assembly includes an industrial piezoelectric nozzle and a negative pressure generating device, and the industrial piezoelectric nozzle is provided with an ink inlet of the nozzle communicated with the negative pressure generating device;

The negative pressure generating device is a hollow structure, one end is provided with a circulating ink supply ink inlet connected with the ink outlet pipeline, and the other end is provided with a circulating ink supply ink outlet connected with the ink return pipeline, through The control module controls the flow rate of the ink outlet of the circulating ink supply to be greater than the flow rate of the ink inlet of the circulating ink supply, so as to form a negative pressure printing environment of the industrial piezoelectric nozzle.

Further, in an implementation manner, the ink inlet of the nozzle in the negative pressure generating device includes a first ink inlet and a second ink inlet, and the ink inlet of the first nozzle and the second ink inlet The ink ports are all inverted conical cavity structures.

Further, in an implementation manner, the ink return pipeline includes an ink return damper and an ink return diaphragm pump that are sequentially communicated through an opaque ink tube;

One end of the ink return damper communicates with the ceramic ink piezoelectric print head assembly, and the other end communicates with the ink return diaphragm pump, which is used to remove the pressure pulse generated when the ink return diaphragm pump works, and reduce the flow rate fluctuation of the ceramic ink ;

One end of the ink return diaphragm pump communicates with the ink return damper, and the other end communicates with the ink return port of the secondary ceramic ink container for recovering the ceramic ink in the ceramic ink piezoelectric print head assembly.

Further, in an implementation manner, the sensors in the circulating ink supply module include: a liquid level sensor, a flow sensor and a temperature sensor;

The liquid level sensor is located in the secondary ceramic ink container and the primary ceramic ink container, and is used to obtain the remaining ink volume of the secondary ceramic ink container and the ink residual volume of the primary ceramic ink container; The primary ceramic ink container communicates with the secondary ceramic ink container through a diaphragm pump and a filter, and is used for supplementing from the primary ceramic ink container when the remaining ink in the secondary ceramic ink container is insufficient. In the present invention, after the software module obtains the ink remaining amount of the liquid level sensor, it judges whether the ink remaining amount is sufficient according to the comparison result of the ink remaining amount and the threshold value, if the ink remaining amount of the first-stage ceramic ink container Insufficient, the software module generates an alarm message indicating insufficient ink remaining.

The flow sensor and the temperature sensor are arranged at both ends of the ceramic ink piezoelectric print head assembly for obtaining the ink flow rate and ink temperature, the ink flow rate includes the ink flow rate and the ink return flow rate, and the ink temperature includes the ink output temperature and the ink temperature. Ink return temperature.

Further, in an implementation manner, the software module sets the negative pressure environment parameter, the negative pressure environment parameter is the negative pressure value required for the operation of the negative pressure generating device, combined with the negative pressure environment parameter and ink characteristics The flow rate control parameters are calculated, and the corresponding flow rate control commands generated according to the flow rate control parameters are sent to the control module, and the ink characteristics include ink viscosity characteristics and ink temperature characteristics;

The control module controls the speed of the ink return diaphragm pump and the speed of the ink outlet diaphragm pump through the PID algorithm after obtaining the ink flow rate according to the flow rate control parameter and the flow rate control command, that is, controls the flow rate of the circulating ink supply and the ink output. Ink return flow rate.

Further, in an implementation manner, the software module determines the optimal ceramic ink temperature according to the ink viscosity characteristics, and uses the ink outlet temperature and the ink return temperature corresponding to the optimal ceramic ink temperature as temperature control parameters, and according to The temperature control parameters generate corresponding temperature control commands and send them to the control module;

The control module controls the average heating power of the temperature-controlled heater in the ink outlet pipeline according to the temperature control parameters and temperature control commands to heat the ceramic ink flowing into the ceramic ink print head assembly.

Further, in an implementation manner, the control module includes a control unit and an uninterruptible power supply unit;

The control unit is configured to receive control commands and control parameters of the software module, and return the state of the ink supply system to the software module;

The uninterruptible power supply unit is used to provide the power required to correctly shut down the ink supply system according to the process when the ink supply system suddenly loses power;

The negative pressure cleaning module also includes a negative pressure generator, which is used to generate the negative pressure required to attract the ceramic ink and particles in the nozzle of the ceramic ink piezoelectric print head assembly; and a rubber sleeve, which is used to tightly wrap the nozzle; and Nozzles for spraying cleaning fluid;

The ink supply system also includes an ink drop observation module, the ink drop observation module includes a high-speed camera module, an auto-focus mechanism and an ink drop quality analysis software system for analyzing the ink output of the circulating ink supply module.

In the prior art, the ink printing device is not suitable for the printing of ceramic ink, resulting in unstable printing, and precipitation and clogging during the printing process. However, with the aforementioned system, the ink supply module, control module, software module and negative pressure cleaning are used to The cooperation of the modules realizes the stable printing of the ceramic ink and at the same time avoids the problem of sedimentation and clogging. Therefore, compared with the prior art, the present invention can improve the performance of industrial nozzles for printing high-sedimentation inks, reduce the risk of nozzle clogging to a large extent, prolong the life of industrial nozzles, and thus improve economic benefits.

Description of drawings

In order to illustrate the technical solution of the present invention more clearly, the accompanying drawings that need to be used in the embodiments will be briefly introduced below. Obviously, for those of ordinary skill in the art, on the premise of not paying creative work, they can also Additional figures can be derived from these figures.

Fig. 1 is a schematic structural view of an ink supply system for ceramic ink printing provided in the embodiment part of the present invention;

2 is a schematic structural view of a ceramic ink piezoelectric print head assembly in an ink supply system for ceramic ink printing provided in the embodiments of the present invention;

Fig. 3 is a schematic structural diagram of a flow sensor and a temperature sensor in an ink supply system for ceramic ink printing provided in the embodiments of the present invention;

4 is a schematic structural view of a secondary ceramic ink container and a primary ceramic ink container provided with an agitator in an ink supply system for ceramic ink printing provided in the embodiment of the present invention;

5 is a schematic diagram of a temperature PID control model in an ink supply system for ceramic ink printing provided in the embodiments of the present invention;

Fig. 6 is a schematic diagram of the observation results of the ink drop observation module in an ink supply system for ceramic ink printing provided in the embodiment part of the present invention;

Fig. 7 is a schematic flow chart of an ink supply method for ceramic ink printing provided in the embodiment part of the present invention;

Among them, 10-circulating ink supply module, 101-ink outlet pipeline, 1011-secondary ceramic ink container, 10111-ink outlet, 10112-ink return port, 1012-three-way solenoid valve, 1013-ink outlet diaphragm pump, 1014-Ink outlet damper, 1015-Filtration and exhaust device, 10151-Drain hole, 10152-Ink tube, 1016-Temperature control heater, 1017-Air filter, 102-Ceramic ink piezoelectric print head assembly, 1021 -Industrial piezoelectric nozzle, 10211-Ink inlet of the nozzle, 102111-Ink inlet of the first nozzle, 102112-Ink inlet of the second nozzle, 10212-Ink outlet of the nozzle, 1022-Negative pressure generating device, 10221-Circular ink supply Ink inlet, 10222-Circulating ink supply and ink outlet, 103-Ink return pipeline, 1031-Ink return damper, 1032-Ink return diaphragm pump, 104-Sensor, 1041-Liquid level sensor, 1042-Flow sensor, 1043 - temperature sensor, 105- primary ceramic ink container, 20- control module, 201- control unit, 202- uninterruptible power supply unit, 30- software module, 40- negative pressure cleaning module, 401- negative pressure generator, 402- Rubber sleeve, 403-nozzle, 50-ink drop observation module.

Detailed ways

In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

The embodiment of the present invention discloses an ink supply system for ceramic ink printing, which is applied in the field of industrial ceramic ink printing, such as ceramic tile printing, ceramic 3D printing and other fields. Ceramic ink has the characteristics of high viscosity and high sedimentation. During the printing process of ceramic ink, it is easy to cause nozzle blockage, ink deposition in the pipeline and other hazards. The traditional negative pressure ink supply system uses a negative pressure pump combined with a secondary ink supply box to generate the working negative pressure required by the nozzle. At this time, the ceramic ink in the secondary ink supply box is almost static, and it is easy to produce precipitation and affect the normal operation of the nozzle.

As shown in FIG. 1 , an embodiment of the present invention provides an ink supply system for ceramic ink printing, including: a circulating ink supply module 10 , a control module 20 , a software module 30 and a negative pressure cleaning module 40 ;

The circulating ink supply module 10 includes a circulating ink outlet pipeline 101, a ceramic ink piezoelectric print head assembly 102 and an ink return pipeline 103 for forming a negative pressure printing environment, and receiving the control of the software module 30 After ordering and controlling parameters, ceramic ink printing and ink circulation are realized; the ink circulation module 10 also includes a sensor 104, which is used to obtain the data and status of the ink supply system and send them to the control module 20;

Specifically, in Fig. 1, the ink outlet pipeline 101 and the ink return pipeline 103 are not directly shown, but the ink outlet pipeline 101 is along the ink outlet 10111 of the secondary ceramic ink container 1011 to the ceramic ink piezoelectric printing The pipeline shown by the leftward arrow of the head assembly 102, and the ink return pipeline 103 is shown by the rightward arrow along the ceramic ink piezoelectric print head assembly 102 to the ink return port 10112 of the secondary ceramic ink container 1011 out the pipeline.

In this embodiment, the states of the ink supply system mainly include the following:

The first-level ceramic ink container is in an ink-short state. At this time, an alarm message can be generated through the software module, and ink can be manually added to the first-level ceramic ink container;

The secondary ceramic ink container is short of ink, at this time, the control unit controls the diaphragm pump to extract the filtered ceramic ink from the primary ceramic ink container to the secondary ceramic ink container;

Ink printing status, at this time, the ink inlet temperature, ink inlet flow rate, ink outlet temperature and ink outlet flow rate can be obtained according to each sensor in the circulating ink supply module, such as a flow sensor and a temperature sensor;

In the negative pressure cleaning state, the ceramic ink piezoelectric print head assembly is cleaned by the negative pressure cleaning module.

The control module 20 is used to receive the data and status of the ink supply system, and return to the software module 30, after receiving the control command and control parameters sent by the software module 30, transmit them to the ink supply system Each module of the system controls the coordinated operation of each module;

The software module 30 is used to analyze the data and status of the ink supply system, and send control commands and control parameters to the control module 20 according to the analysis results; as shown in Figure 1, in this embodiment, the The software module 30 can be connected to the control module 20 through a communication line to realize the transmission of data and status of the ink supply system.

The negative pressure cleaning module 40 is used for cleaning the ceramic ink piezoelectric print head assembly 102 .

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the ink outlet pipeline 101 includes a secondary ceramic ink container 1011, a three-way solenoid valve 1012, an outlet An ink diaphragm pump 1013, an ink outlet damper 1014, a filter and exhaust device 1015, and a temperature-controlled heater 1016; in this embodiment, the ink outlet diaphragm pump 1013 is a one-way diaphragm pump. In addition, considering the characteristics of ceramic ink, the pipelines in this embodiment are all connected by opaque ink tubes to avoid adverse effects on printing quality.

The secondary ceramic ink container 1011 is provided with an ink outlet 10111 connected to the three-way solenoid valve 1012, and an ink return port 10112 connected to the ink return pipeline 103, which are respectively used for supplying and collecting ceramic ink;

The three-way solenoid valve 1012 determines the working state according to the control command and control parameters sent by the control module 20. When the three-way solenoid valve 1012 determines that the working state is the ink supply state, one end of the three-way solenoid valve 1012 is connected to the ink outlet. The port 10111 communicates, and the other end communicates with the ink outlet diaphragm pump 1013, and the three-way solenoid valve 1012 cooperates with the ink outlet diaphragm pump 1013 to extract the ceramic ink in the secondary ceramic ink container 1011 from the ink outlet 10111;

One end of the ink outlet damper 1014 communicates with the ink outlet diaphragm pump 1013, and the other end communicates with the filter and exhaust device 1015, which is used to remove the pressure pulse generated when the ink outlet diaphragm pump 1013 works, and reduce the pressure of the ceramic ink. flow rate fluctuations;

One end of the filter and exhaust device 1015 communicates with the ink outlet damper 1014, and the other end communicates with the temperature-controlled heater 1016 for heating the ceramic ink filtered by the filter and exhaust device 1015. The exhaust device 1015 is also provided with a discharge hole 10151 and an ink pipe 10152 (not shown) communicated with the discharge hole 10151, and the other end of the ink pipe 10152 communicates with the secondary ceramic ink container 1011 for The air in the ceramic ink and the atomized ink are collected to the secondary ceramic ink container 1011; in the present embodiment, the high-speed ceramic ink mist, ceramic ink mist and ink can be partially atomized when the ink outlet diaphragm pump 1013 works. The air in the filter will return to the secondary ceramic ink container 1011 through the drain hole 10151 of the filter and exhaust device 1015 .

One end of the temperature-controlled heater 1016 communicates with the filter and exhaust device 1015, and the other end communicates with the ceramic ink piezoelectric print head assembly 102, for providing filtered and heated air to the ceramic ink piezoelectric print head assembly 102. ceramic ink. In this embodiment, different ceramic inks have a suitable working temperature. At this temperature, the viscosity characteristics of the ceramic ink are most suitable for printing. The function of the temperature-controlled heater 1016 is to evenly heat the flowing through the wrapped heater Ceramic ink, while ensuring the viscosity of the ink, prevents the thermal curing of the ceramic ink flowing through it.

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the ink outlet pipeline 101 further includes an air filter 1017; When the control parameter determines that the working state is the cleaning state, the opaque ink pipe between the three-way solenoid valve and the ink outlet 10111 is disconnected, the air filter 1017 is connected with the three-way solenoid valve 1012, and the air The filter pumps clean air into the ink supply system through the three-way solenoid valve 1012 to clean all pipelines in the ink supply system.

Specifically, the ink supply system described in this embodiment also includes a printing completion state/system power-off state, that is, the working state is a cleaning state. At this time, through the air filter 1017, the three-way solenoid valve 1012 passes through the air pipe and The outlet end of the air filter 1017 is connected. At this time, what the ink outlet diaphragm pump 1013 extracts is filtered clean air, and the function is to fill the pipeline through which the ceramic ink flows in the entire ink supply system with clean air. , in order to achieve the purpose of cleaning the pipeline.

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the ceramic ink piezoelectric print head assembly 102 includes an industrial piezoelectric nozzle 1021 and a negative pressure generating device 1022, and the industrial piezoelectric nozzle 1021 is set There is an ink inlet 10211 of the nozzle communicated with the negative pressure generating device 1022;

The negative pressure generating device 1022 is a hollow structure, one end is provided with a circulating ink supply inlet 10221 communicating with the ink outlet pipeline 101, and the other end is provided with a circulating ink supply outlet communicating with the ink return pipeline 103. The ink port 10222 is used to form the negative pressure printing environment of the industrial piezoelectric nozzle 1021 through the control module 20 to control the flow rate of the circulating ink supply outlet 10222 to be greater than the flow rate of the circulating ink supply port 10221. In this embodiment, the direction of the circular ink supply ink inlet 10221 and the circular ink supply ink outlet 10222 can be exchanged.

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the ink inlet 10211 of the negative pressure generating device 1022 includes a first ink inlet 102111 and a second ink inlet 102112, The ink inlet 102111 of the first nozzle and the ink inlet 102112 of the second nozzle are both inverted conical cavity structures.

In the prior art, all industrial piezoelectric nozzles need to provide a stable negative pressure to resist the surface tension of the ink and natural gravity. At present, there are generally two ways to generate negative pressure: natural siphon and air negative pressure. The principle of natural siphon is generally only suitable for water-based inks with low viscosity, not for ceramic inks with high viscosity and high sedimentation characteristics; air negative pressure is suitable for many inks. However, its negative pressure control accuracy is poor, and the negative pressure control process has large jitters, which leads to unbalanced negative pressure and affects the final inkjet quality.

In the ink supply system for ceramic ink printing described in this embodiment, there will be a certain amount of air in the cavity of the negative pressure generating device 1022 and have a buffering effect. The ink inlet 102111 of the first nozzle and the second nozzle The inverted conical structure adopted by the ink inlet 102112 can reduce the pressure fluctuation generated when the ceramic ink enters and exits the ink inlet 10211 of the nozzle, which is conducive to quickly replenishing the ceramic ink that is missing after the industrial piezoelectric nozzle inkjet, and at the same time, eliminates the ceramic ink in the ceramic ink. Air, in addition, the inverted conical structure is more suitable for 3D printing, and can reduce the roughness of the printing surface, thereby achieving the effect of improving the printing quality of ceramic ink.

Specifically, in this embodiment, the ink inlet 102111 of the first nozzle and the ink inlet 102112 of the second nozzle in the negative pressure generating device 1022 can be printed and formed by the SLM metal 3D printing process once, and then the interfaces can be refined twice. Processing is achieved.

In addition, in this embodiment, the negative pressure generation principle of the negative pressure generating device 1022 is that when the flow rate of the ink outlet of the negative pressure generating device 1022 is greater than the flow rate of the ink inlet port, by controlling the rotational speed of the ink return diaphragm pump 1032 Greater than the rotational speed of the ink outlet diaphragm pump 1013, that is, the flow rate of the ink outlet port is controlled to be greater than the flow rate of the ink inlet port, and negative pressure can be generated. The average value of the generated negative pressure PM=(PIN+POUT)/2, where PIN is the ink inlet port Pressure, POUT is the ink outlet pressure, PM is a negative value.

The greater the ink inlet and outlet pressure (ΔP=PIN−POUT), the higher the flow rate in the negative pressure generating device 1022 . The high-speed flowing ceramic ink can take away unnecessary particles and bubbles, which can reduce the particles in the ink from clogging the piezoelectric nozzle, maintain the printing consistency of the industrial piezoelectric nozzle 1021, and improve the working life of the industrial piezoelectric nozzle 1021.

Specifically, ignoring the pipeline friction of the ink supply system and only considering the fluid impedance I of the negative pressure generating device 1022, then ΔP=μF _L *I*L _viscosity . In the formula, μ is the calculation coefficient, which needs to be calculated separately for different types of print heads, F _L is the ink flow rate, and L _viscosity is the ink viscosity.

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the ink return pipeline 103 includes an ink return damper 1031 and an ink return diaphragm pump 1032 that are sequentially communicated through an opaque ink tube; in this embodiment In an example, the ink return diaphragm pump 1032 is a one-way diaphragm pump.

One end of the ink return damper 1031 communicates with the ceramic ink piezoelectric print head assembly 102, and the other end communicates with the ink return diaphragm pump 1032, which is used to remove the pressure pulse generated when the ink return diaphragm pump 1032 works, and reduce the pressure of the ceramic ink. Ink flow rate fluctuations;

One end of the ink return diaphragm pump 1032 is communicated with the ink return damper 1031, and the other end is communicated with the ink return port 10112 of the secondary ceramic ink container 1011, for reclaiming the ceramic in the ceramic ink piezoelectric print head assembly 102 ink.

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the sensor 104 in the circulating ink supply module 10 includes: a liquid level sensor 1041, a flow sensor 1042 and a temperature sensor 1043;

The liquid level sensor 1041 is arranged in the secondary ceramic ink container 1011 and the primary ceramic ink container 105, and is used to obtain the remaining ink of the secondary ceramic ink container 1011 and the ink remaining of the primary ceramic ink container 105 respectively. The primary ceramic ink container 105 communicates with the secondary ceramic ink container 1011 through a diaphragm pump and a filter, for when the ink remaining in the secondary ceramic ink container 1011 is insufficient, the primary ceramic ink Replenish in the container 105; In the present invention, after the ink remaining quantity of liquid level sensor 1041 is acquired, the software module 30 judges whether the ink remaining quantity is sufficient according to the comparison result of the ink remaining quantity and the threshold value. If the ink level in the ceramic ink container 105 is insufficient, the software module 30 generates an alarm message indicating that the ink level is insufficient.

In this embodiment, the first-stage ceramic ink container 105 adopts an opaque container with a large volume. Specifically, the large volume is enough to meet the volume of printing in one shift, and can provide ceramic ink required for long-time printing. Compared with the primary ceramic ink container 105 , the secondary ceramic ink container 1011 adopts a container with a smaller volume. In addition, since the ceramic ink belongs to the high-precipitation ink, agitators can be installed in the primary ceramic ink container 105 and the secondary ceramic ink container 1011, and the continuous agitation of the agitator can prevent the ceramic ink from settling. Specifically, this The embodiment does not limit the specific shape of the stirrer, as long as it can realize the stirring function of the ceramic ink, as shown in FIG. 4 , the optional stirrer includes, for example, a structure in which the stirring blades are driven by a motor to rotate.

The flow sensor 1042 and the temperature sensor 1043 are arranged at both ends of the ceramic ink piezoelectric print head assembly 102, and are used to obtain the ink flow rate and the ink temperature, the ink flow rate includes the flow rate of the ink output and the flow rate of the ink return, and the temperature of the ink includes the flow rate of the ink output Ink temperature and ink return temperature. As shown in Figure 3, the arrow next to IN and its side indicates the ink outlet pipeline 101, and the arrow next to OUT and its side indicates the ink return pipeline 103; the ink flow rate and temperature measured at the ink outlet pipeline 101 represent the flow of ceramic ink. The ink flow velocity and temperature of the piezoelectric print head assembly 102, that is, the ink flow velocity and the ink outlet temperature; in the same way, the ink flow velocity and temperature measured at the ink return pipeline 103 represent the flow rate of the ceramic ink piezoelectric print head assembly 102. Ink flow rate and temperature, that is, ink return flow rate and ink return temperature.

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the software module 30 sets negative pressure environment parameters, and the negative pressure environment parameters are the negative pressure values required for the negative pressure generating device 1022 to work , calculate the flow rate control parameters in combination with the negative pressure environment parameters and ink characteristics, generate corresponding flow rate control commands according to the flow rate control parameters and send them to the control module 20, the ink characteristics include ink viscosity characteristics and ink temperature characteristics; specifically Yes, in this embodiment, there is no limitation on how to calculate the negative pressure value required for the negative pressure generating device 1022 to work, and it can be obtained by using any calculation method known to those skilled in the art.

The control module 20 controls the speed of the ink return diaphragm pump 1032 and the speed of the ink discharge diaphragm pump 1013 through the PID algorithm after obtaining the ink flow rate according to the flow rate control parameter and the flow rate control command, that is, controls the cycle of ink supply. Ink flow rate and ink return flow rate.

Specifically, in this embodiment, the ink flow rate is obtained through the flow sensor 1042 . The control module 20 corrects the set value of the temperature-controlled heater 1016 by detecting the values of the two flow sensors and the values of the two temperature sensors. More accurate correction needs to consider the length of the ink tube between several sensors.

The temperature PID control model is shown in Figure 5. In Figure 5, r(t) represents the set temperature, y(t) represents the temperature measured by the sensor, e(t)=r(t)–y(t), and P is Proportional item coefficient, I is the integral item coefficient, D is the differential item coefficient, and the actual control generally adopts PI control, that is, the coefficient D is 0. The coefficient of the proportional item affects the response speed of the control system, and the integral item is used to reduce the cumulative error. The coefficients are adjusted according to the empirical value and the actual test value. The system output u(t) is the PWM duty cycle, which is used to control the average value of the voltage applied to the heater, thereby controlling the heating process

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the software module 30 determines the optimal ceramic ink temperature according to the ink viscosity characteristics, and the ink output temperature corresponding to the optimal ceramic ink temperature and Ink return temperature is used as a temperature control parameter, and a corresponding temperature control command is generated according to the temperature control parameter and sent to the control module 20; specifically, in this embodiment, different ceramic inks need to test the viscosity-temperature curve, for new For ceramic ink, the software module 30 needs to judge the proper printing temperature of the ceramic ink through the ink drop observation module.

The control module 20 controls the average heating power of the temperature-controlled heater 1016 in the ink outlet pipeline 101 according to the temperature control parameters and temperature control commands to heat the ceramic ink flowing into the ceramic ink print head assembly. In addition, the software module 30 calculates and obtains the temperature required by the ink in the ceramic ink piezoelectric print head assembly 102 according to the ink return temperature and ink return flow rate obtained by the temperature sensor 1043. According to the ceramic ink piezoelectric print head The deviation between the required temperature of the ink in the component 102 and the optimal ceramic ink temperature is obtained to obtain the required temperature of the ink flowing into the ceramic nozzle assembly; and according to the calculated temperature of the ink required to flow into the ceramic nozzle assembly, generate temperature adjustment parameters, and generate corresponding temperature adjustment commands according to the temperature adjustment parameters and send them to the control module.

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the control module 20 includes a control unit 201 and an uninterruptible power supply (Uninterruptible Power Supply, UPS) unit 202;

The control unit 201 is configured to receive control commands and control parameters of the software module 30, and return the state of the ink supply system to the software module 30;

The uninterruptible power supply unit 202 is used for providing the power required for shutting down the ink supply system correctly according to the procedure when the ink supply system suddenly loses power. Therefore, when the ink supply system suddenly loses power, the entire ink supply system can continue to operate, so that the system can return to a safe closed state according to normal operation logic.

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the negative pressure cleaning module 40 includes a negative pressure generator 401 for generating suction in the nozzles of the ceramic ink piezoelectric print head assembly 102. Negative pressure required for ceramic ink and particles; and rubber sleeve 402 for tightly wrapping the nozzle; and nozzle 403 for spraying cleaning liquid. In this embodiment, the negative pressure generator 401 , the rubber sleeve 402 and the nozzle 403 are not shown in the figure. In this embodiment, the use of the negative pressure generator 401 can make the tiny particles and ink in the industrial piezoelectric nozzle 1021 more easily ejected.

In an ink supply system for ceramic ink printing provided by an embodiment of the present invention, the ink supply system further includes an ink drop observation module 50, and the ink drop observation module includes a high-speed camera module, an auto-focus mechanism, and an ink drop observation module. The quality analysis software system is used to analyze the ink output of the circulating ink supply module 10 . In this embodiment, the ink drop observation module 50 monitors the state of the ink drop (including shape, size, ejection speed) ejected by the industrial piezoelectric nozzle 1021 at regular intervals (can be set by the system control software) through the high-speed camera module. , tailing degree, etc.), analyze the current state of the industrial piezoelectric print head 1021 through the image algorithm of the system control software, and judge whether it is necessary to clean the ceramic ink piezoelectric print head assembly 102 or adjust the system parameters of the circulating ink supply module 10.

Specifically, in this embodiment, the high-speed camera module is fixed at the installation position of the entire device. During the ink drop state monitoring task time period, the ceramic inkjet printing equipment (not included in the scope of this patent) controls the inkjet printing The head moves to a fixed monitoring point and triggers the camera to shoot. Observing the state of the ink drop includes the shape of the ink drop, the size of the ink drop, the exit speed of the ink drop, and whether the ink drop trails, as shown in Figure 6. During ink drop status monitoring, the inkjet print head ejects ceramic ink at a fixed frequency. When there is no ink ejection in a position, it indicates that the nozzle is clogged and needs to be cleaned; when the ink drop is observed to be trailing and the size deviation is too large , it is necessary to adjust the drive waveform of the nozzle, including reducing the pulse rise time of the high-voltage drive waveform and increasing the voltage of the high-voltage drive waveform.

As shown in FIG. 7, according to an ink supply system for ceramic ink printing described in this embodiment, this embodiment also provides a ceramic ink printing method, which can realize the following printing process:

Step 1, correctly connect the connection lines, communication lines and pipelines of each module of the ink supply system;

Step 2, manually filling the ceramic printing ink into the primary ceramic ink container 105;

Step 3, the control unit 201 controls the diaphragm pump and the filter to extract the ceramic ink from the primary ceramic ink container 105 to the secondary ceramic ink container 1011;

Step 4, the ink outlet diaphragm pump 1013 and the ink return diaphragm pump 1032 work, and the system obtains the return data from the flow sensor 1042 and the temperature sensor 1043, so that the ceramic ink piezoelectric print head assembly 102 works in a suitable pressure state;

Step 5, move the ceramic ink piezoelectric print head assembly 102 to the ink drop state observation position, cooperate with the ink drop observation module 50 to test the ink drop ejection state, and adjust the driving parameters;

Step 6: Print with ceramic ink according to the printing process;

Step 7: Monitor the inkjet status of the nozzle according to the set time. If the status of the nozzle is unqualified, enter the cleaning process of the nozzle;

Step 8, after the nozzle cleaning process is completed, continue to print with ceramic ink.

In summary, the present embodiment provides an ink supply system for ceramic ink printing, including: a circulating ink supply module, a control module, a software module and a negative pressure cleaning module; The ink outlet pipeline, ceramic ink piezoelectric print head assembly and ink return pipeline are used to form a negative pressure printing environment, and after receiving the control commands and control parameters of the software module, realize ceramic ink printing and ink supply circulation; The circulating ink supply module further includes a sensor for acquiring the data and status of the ink supply system and sending them to the control module; the control module is used for receiving the data and status of the ink supply system, and Returning to the software module, after receiving the control command and control parameters sent by the software module, transmit them to each module of the ink supply system, and control the coordinated operation of each module; the software module is used to analyze the The data and status of the ink supply system, and send control commands and control parameters to the control module according to the analysis results; the negative pressure cleaning module is used to clean the ceramic ink piezoelectric print head assembly.

Other embodiments of the application will be readily apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. This application is intended to cover any modification, use or adaptation of the application, these modifications, uses or adaptations follow the general principles of the application and include common knowledge or conventional technical means in the technical field not disclosed in the application . The specification and examples are to be considered exemplary only, with a true scope and spirit of the application indicated by the following claims.

It should be understood that the present application is not limited to the precise constructions which have been described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the application is limited only by the appended claims.

Claims

An ink supply system for ceramic ink printing, characterized in that it includes: a circulating ink supply module, a control module, a software module and a negative pressure cleaning module;

The circulating ink supply module includes a circulating ink outlet pipeline, a ceramic ink piezoelectric print head assembly and an ink return pipeline for forming a negative pressure printing environment, and after receiving the control command and control parameters of the software module , to realize ceramic ink printing and ink circulation; the ink circulation module also includes a sensor for acquiring the data and status of the ink supply system and sending them to the control module;

The control module is used to receive the data and status of the ink supply system, and return to the software module, after receiving the control command and control parameters sent by the software module, transmit them to each of the ink supply system module, controlling the cooperative operation of each module;

The software module is used to analyze the data and status of the ink supply system, and send control commands and control parameters to the control module according to the analysis results;

The negative pressure cleaning module is used for cleaning the ceramic ink piezoelectric print head assembly.
An ink supply system for ceramic ink printing according to claim 1, wherein the ink outlet pipeline includes a secondary ceramic ink container, a three-way solenoid valve, Ink outlet diaphragm pump, ink outlet damper, filter and exhaust device and temperature control heater;

The secondary ceramic ink container is provided with an ink outlet connected to the three-way solenoid valve, and an ink return port connected to the ink return pipeline, which are respectively used to provide and collect ceramic ink;

The three-way solenoid valve determines the working state according to the control command and control parameters sent by the control module. When the three-way solenoid valve determines that the working state is the ink supply state, one end of the three-way solenoid valve communicates with the ink outlet, and the other end of the three-way solenoid valve communicates with the ink outlet. One end communicates with the ink outlet diaphragm pump, and the three-way solenoid valve cooperates with the ink outlet diaphragm pump to extract the ceramic ink in the secondary ceramic ink container from the ink outlet;

One end of the ink outlet damper communicates with the ink outlet diaphragm pump, and the other end communicates with the filter and exhaust device, which is used to remove the pressure pulse generated when the ink outlet diaphragm pump works, and reduce the flow rate fluctuation of the ceramic ink;

One end of the filter and exhaust device communicates with the ink outlet damper, and the other end communicates with the temperature-controlled heater for heating the ceramic ink filtered by the filter and exhaust device. There is also a drain hole and an ink tube communicating with the drain hole, the other end of the ink tube communicates with the secondary ceramic ink container for collecting the air in the ceramic ink and the atomized ink to the secondary ceramic ink container;

One end of the temperature-controlled heater communicates with the filter and exhaust device, and the other end communicates with the ceramic ink piezoelectric print head assembly, for providing filtered and heated ceramic ink to the ceramic ink piezoelectric print head assembly.
An ink supply system for ceramic ink printing according to claim 2, wherein the ink outlet pipeline also includes an air filter; when the three-way solenoid valve is sent according to the control command and When the control parameter determines that the working state is the cleaning state, the opaque ink tube between the three-way solenoid valve and the ink outlet is disconnected, the air filter is connected with the three-way solenoid valve, and the air filter passes through the three-way solenoid valve. Clean air is pumped into the ink supply system through the solenoid valve to clean all pipelines in the ink supply system.
An ink supply system for ceramic ink printing according to claim 1, wherein the ceramic ink piezoelectric print head assembly includes an industrial piezoelectric nozzle and a negative pressure generating device, and the industrial piezoelectric nozzle is provided with There is an ink inlet port of the nozzle communicated with the negative pressure generating device;

The negative pressure generating device is a hollow structure, one end is provided with a circulating ink supply ink inlet connected with the ink outlet pipeline, and the other end is provided with a circulating ink supply ink outlet connected with the ink return pipeline, through The control module controls the flow rate of the ink outlet of the circulating ink supply to be greater than the flow rate of the ink inlet of the circulating ink supply, so as to form a negative pressure printing environment of the industrial piezoelectric nozzle.
The ink supply system for ceramic ink printing according to claim 4, wherein the nozzle ink inlet in the negative pressure generating device includes a first nozzle ink inlet and a second nozzle ink inlet, Both the ink inlet of the first nozzle and the ink inlet of the second nozzle have an inverted conical cavity structure.
An ink supply system for ceramic ink printing according to claim 2, wherein the ink return pipeline includes an ink return damper and an ink return diaphragm pump that are sequentially communicated through an opaque ink tube;

One end of the ink return damper communicates with the ceramic ink piezoelectric print head assembly, and the other end communicates with the ink return diaphragm pump, which is used to remove the pressure pulse generated when the ink return diaphragm pump works, and reduce the flow rate fluctuation of the ceramic ink ;

One end of the ink return diaphragm pump communicates with the ink return damper, and the other end communicates with the ink return port of the secondary ceramic ink container for recovering the ceramic ink in the ceramic ink piezoelectric print head assembly.
An ink supply system for ceramic ink printing according to claim 2, wherein the sensors in the circulating ink supply module include: a liquid level sensor, a flow sensor and a temperature sensor;

The liquid level sensor is located in the secondary ceramic ink container and the primary ceramic ink container, and is used to obtain the remaining ink volume of the secondary ceramic ink container and the ink residual volume of the primary ceramic ink container; The first-level ceramic ink container is communicated with the second-level ceramic ink container through a diaphragm pump and a filter, and is used for supplementing from the first-level ceramic ink container when the ink balance of the second-level ceramic ink container is insufficient;

The flow sensor and the temperature sensor are arranged at both ends of the ceramic ink piezoelectric print head assembly for obtaining the ink flow rate and ink temperature, the ink flow rate includes the ink flow rate and the ink return flow rate, and the ink temperature includes the ink output temperature and the ink temperature. Ink return temperature.
An ink supply system for ceramic ink printing according to claim 1, wherein the software module sets negative pressure environment parameters, and the negative pressure environment parameters are the negative pressure required for the negative pressure generating device to work. The pressure value is calculated in combination with the negative pressure environment parameters and ink characteristics to obtain flow rate control parameters, and a corresponding flow rate control command is generated according to the flow rate control parameters and sent to the control module. The ink characteristics include ink viscosity characteristics and ink temperature characteristics;

The control module controls the speed of the ink return diaphragm pump and the speed of the ink discharge diaphragm pump through the PID algorithm after obtaining the ink flow rate according to the flow rate control parameter and the flow rate control command, that is, controls the circulating ink supply and ink output Flow rate and ink return flow rate.
The ink supply system for ceramic ink printing according to claim 8, wherein the software module determines the optimum ceramic ink temperature according to the viscosity characteristics of the ink, and outputs the temperature corresponding to the optimum ceramic ink temperature. Ink temperature and ink return temperature are used as temperature control parameters, and corresponding temperature control commands are generated according to the temperature control parameters and sent to the control module;

The control module controls the average heating power of the temperature-controlled heater in the ink outlet pipeline according to the temperature control parameters and temperature control commands to heat the ceramic ink flowing into the ceramic ink print head assembly.
The ink supply system for ceramic ink printing according to claim 1, wherein the control module includes a control unit and an uninterruptible power supply unit;

The control unit is configured to receive control commands and control parameters of the software module, and return the state of the ink supply system to the software module;

The uninterruptible power supply unit is used to provide the power required to correctly shut down the ink supply system according to the process when the ink supply system suddenly loses power;

The negative pressure cleaning module also includes a negative pressure generator, which is used to generate the negative pressure required to attract the ceramic ink and particles in the nozzle of the ceramic ink piezoelectric print head assembly; and a rubber sleeve, which is used to tightly wrap the nozzle; and Nozzles for spraying cleaning fluid;

The ink supply system also includes an ink drop observation module, the ink drop observation module includes a high-speed camera module, an auto-focus mechanism and an ink drop quality analysis software system for analyzing the ink output of the circulating ink supply module.