An ink supply system, a digital printing apparatus, and an ink supply control method

Abstract

The application discloses an ink supply system, a digital printing equipment and an ink supply control method, and particularly relates to the technical field of digital printing equipment. The ink supply system comprises a gas supply device, a negative pressure pump, an ink supply cavity, an ink return cavity and an ink locking assembly. The gas inlet end of the ink supply cavity is communicated with the gas supply device, and the liquid outlet end of the ink supply cavity is adapted to be communicated with the liquid inlet of a printing nozzle. The gas outlet end of the ink return cavity is communicated with the negative pressure pump, and the liquid inlet end of the ink return cavity is adapted to be communicated with the liquid outlet of the printing nozzle. The ink locking assembly is arranged on the positive pressure gas pipeline and the negative pressure gas pipeline, and is used for limiting the ink flow into the printing nozzle when the printing nozzle stops working or power failure. The application improves the ink supply system and the ink supply control method, and the ink control is more accurate and effective. The problem that the ink still flows out through the nozzle when the equipment stops working or suddenly power failure is solved, and the application is safer and more reliable. Meanwhile, the problem that the printing pattern has color difference caused by the ink temperature rising due to the heating of the electromagnetic valve is avoided.

Description

Technical Field

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

[0002] In existing technologies, during digital printing of textiles, to prevent ink from flowing out of the print head when the equipment stops working, a shut-off valve is usually added between the ink bottle and the print head. When the equipment stops working or suddenly loses power, the shut-off valve closes directly to prevent ink from flowing out of the print head.

[0003] However, the above control methods have many shortcomings. In order to take into account the situation where the equipment stops working due to a sudden power failure, the on-off valve is usually a normally closed electric valve. Once the electric valve is damaged or the valve core is stuck, the electric valve cannot lock the ink, which poses a safety hazard to the equipment. In addition, the on-off valve is powered on for a long time, and the valve body will heat up, which will affect the temperature of the ink flowing through the valve body, thus causing color difference in the printed pattern. Summary of the Invention

[0004] The main objective of this invention is to provide an ink supply system, a digital printing device, and an ink supply control method, which aims to solve the problem that ink still flows out of the printhead when the device stops working or there is a sudden power outage, and to avoid the problem of color difference in the printed pattern caused by ink heating due to the heating of the solenoid valve.

[0005] To achieve the above objectives, the present invention proposes an ink supply system for supplying ink to a printhead, comprising:

[0006] Gas supply device;

[0007] Negative pressure pump;

[0008] The ink supply chamber has an air inlet connected to the air supply device via a positive pressure gas pipe, and an ink outlet adapted to be connected to the ink inlet of the print head.

[0009] The ink return chamber has an air outlet connected to the negative pressure pump via a negative pressure gas pipe, and an inlet adapted to connect to the outlet of the print head; and

[0010] An ink-locking assembly is provided on the positive pressure gas pipe and / or the negative pressure gas pipe to restrict the flow of ink from the ink supply chamber and the ink return chamber to the print head when the print head stops working or is powered off.

[0011] Optionally, the ink-locking assembly includes a first valve and a second valve, the first valve being located on the positive pressure gas pipeline and the second valve being located on the negative pressure gas pipeline; the ink supply system further includes a buffer, the buffer being located on the negative pressure gas pipeline and between the second valve and the ink return chamber, to ensure stable gas pressure;

[0012] When the print head is working normally, the first valve is not connected to the negative pressure gas pipeline, and the second valve is open;

[0013] When the printhead stops working or there is a power outage, the first valve is connected to the buffer, or the first valve is connected to the negative pressure gas pipeline between the second valve and the buffer, and the second valve is closed.

[0014] Optionally, the first valve is a three-way solenoid valve, with the first end of the three-way solenoid valve connected to the air supply device, the second end of the three-way solenoid valve connected to the ink supply chamber, and the third end of the three-way solenoid valve connected to the buffer.

[0015] Optionally, the second valve is a pressure-locking valve.

[0016] Optionally, the ink supply system further includes a positive pressure regulating valve, which is located on the positive pressure gas pipeline between the gas supply device and the first valve.

[0017] Optionally, the ink supply system further includes a negative pressure regulating valve, which is located on the negative pressure gas pipeline between the negative pressure pump and the second valve.

[0018] Optionally, the ink supply system further includes a filter connected to the negative pressure pump.

[0019] To achieve the above objectives, the present invention also provides a digital printing device, comprising:

[0020] Print head; and

[0021] The ink supply system described above, wherein the ink supply system is in cyclic communication with the printhead, and the ink supply system is used to supply ink to the printhead, includes:

[0022] Gas supply device;

[0023] Negative pressure pump;

[0024] The ink supply chamber has an air inlet connected to the air supply device via a positive pressure gas pipe, and an ink outlet adapted to be connected to the ink inlet of the print head.

[0025] The ink return chamber has an air outlet connected to the negative pressure pump via a negative pressure gas pipe, and an inlet adapted to connect to the outlet of the print head; and

[0026] An ink-locking assembly is provided on the positive pressure gas pipe and / or the negative pressure gas pipe to restrict the flow of ink from the ink supply chamber and the ink return chamber to the print head when the print head stops working or is powered off.

[0027] To achieve the above objectives, the present invention also proposes an ink supply control method for an ink supply system, the ink supply control method comprising the following steps:

[0028] The second valve is closed upon receiving a shutdown or power failure signal.

[0029] The second and third ports of the first valve are connected and the first port is closed to allow gas in the negative pressure gas pipeline to be introduced into the positive pressure gas pipeline and to balance the gas in the pipeline to the target negative pressure value.

[0030] Optionally, the ink supply control method further includes the following steps:

[0031] Upon receiving the power-on signal, the positive pressure regulating valve is opened, and the first port of the first valve is connected to the second port while its third port is closed, so that positive pressure gas can enter the ink supply chamber.

[0032] Open the negative pressure regulating valve and the second valve to allow negative pressure gas to enter the ink return chamber, and allow ink to flow from the ink supply chamber to the print head, and then flow back to the ink return chamber.

[0033] In the technical solution of the present invention, the ink supply system includes an air supply device, a negative pressure pump, an ink supply chamber, an ink return chamber, and an ink locking assembly; the air inlet of the ink supply chamber is connected to the air supply device through a positive pressure gas pipeline, and the liquid outlet of the ink supply chamber is adapted to connect to the liquid inlet of the print head; the air outlet of the ink return chamber is connected to the negative pressure pump through a negative pressure gas pipeline, and the liquid inlet of the ink return chamber is adapted to connect to the liquid outlet of the print head; the ink locking assembly is disposed on the positive pressure gas pipeline and / or the negative pressure gas pipeline to restrict the flow of ink in the ink supply chamber and the ink return chamber to the print head when the print head stops working or is powered off. It is understandable that when the equipment suddenly loses power or stops working, the ink-locking component effectively restricts the flow of ink from the ink supply and return chambers to the printhead by balancing the gas pressure in the pipeline. This ensures that both the ink supply and return chambers are under the same negative pressure, preventing the ink from dripping from the printhead surface. This effectively solves the problem of ink still flowing from the printhead when the equipment stops working or experiences a sudden power outage. Furthermore, because this ink-locking component is not located between the ink supply chamber and the printhead, it does not affect the temperature of the ink entering the printhead during printing. This avoids color differences in the printed pattern caused by ink overheating due to the solenoid valve, significantly improving print quality. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0035] Figure 1 This is a structural block diagram of an embodiment of the digital printing equipment of the present invention;

[0036] Figure 2 This is a structural block diagram of an embodiment of the ink supply system of the present invention;

[0037] Figure 3 This is a flowchart illustrating an embodiment of the ink supply control method of the ink supply system of the present invention. Figure 1 ;

[0038] Figure 4 This is a flowchart illustrating an embodiment of the ink supply control method of the ink supply system of the present invention. Figure 2 .

[0039] Explanation of icon numbers:

[0040] 100. Ink supply system; 200. Print head; 10. Air supply device; 20. Negative pressure pump; 30. Ink supply chamber; 40. Ink return chamber; 50. Ink lock assembly; 51. First valve; 52. Second valve; 60. Buffer; 70. Positive pressure regulating valve; 80. Negative pressure regulating valve; 90. Filter.

[0041] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0043] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0044] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0045] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the word "and / or" throughout the text means including three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0046] This invention proposes an ink supply system applicable to various devices that require ink supply, particularly digital printing equipment, but not limited thereto.

[0047] Reference Figure 1 and Figure 2 In one embodiment of the present invention, the ink supply system 100 includes an air supply device 10, a negative pressure pump 20, an ink supply chamber 30, an ink return chamber 40, and an ink locking assembly 50; the air inlet of the ink supply chamber 30 is connected to the air supply device 10 through a positive pressure gas pipeline, and the liquid outlet of the ink supply chamber 30 is adapted to connect to the liquid inlet of the print head 200; the air outlet of the ink return chamber 40 is connected to the negative pressure pump 20 through a negative pressure gas pipeline, and the liquid inlet of the ink return chamber 40 is adapted to connect to the liquid outlet of the print head 200; the ink locking assembly 50 is disposed on the positive pressure gas pipeline and / or the negative pressure gas pipeline to restrict the flow of ink in the ink supply chamber 30 and the ink return chamber 40 into the print head 200 when the print head 200 stops working or is powered off.

[0048] In this embodiment, the gas supply device 10 is a device capable of generating compressed gas, such as an air compressor, which can compress atmospheric pressure into a relatively positive pressure value. The negative pressure pump 20 is a vacuum pump used to create negative pressure and allow the gas in the pipeline to be extracted under atmospheric pressure, so as to extract the atmospheric pressure gas in the internal cavity of the ink return chamber 40 into a relatively negative pressure value.

[0049] The ink-locking assembly 50 may include a valve or device that can be manually or electrically controlled, or a valve or device that has a gas pressure regulating function, without limitation herein.

[0050] It is understandable that when the equipment suddenly loses power or stops working, the ink-locking component 50 can effectively limit the flow of ink from the ink supply chamber 30 and the ink return chamber 40 to the print head 200 by balancing the gas pressure in the pipeline. This ensures that both the ink supply chamber 30 and the ink return chamber 40 are under the same negative pressure, which holds the ink back and prevents it from dripping from the surface of the print head 200. This effectively solves the problem of ink still flowing out of the print head when the equipment stops working or suddenly loses power. Furthermore, since the ink-locking component 50 is not located between the ink supply chamber 30 and the print head 200, it does not affect the temperature of the ink entering the print head 200 during printing. This avoids the problem of color difference in the printed pattern caused by ink overheating due to the solenoid valve, significantly improving the printing quality.

[0051] Reference Figure 2In one embodiment, the ink-locking assembly 50 may include a first valve 51 and a second valve 52, the first valve 51 being disposed on a positive pressure gas pipeline and the second valve 52 being disposed on a negative pressure gas pipeline; the ink supply system 100 further includes a buffer 60, which is disposed on the negative pressure gas pipeline and located between the second valve 52 and the ink return chamber 40, in order to ensure stable gas pressure.

[0052] When the print head 200 is working normally, the first valve 51 is not connected to the negative pressure gas pipeline, and the second valve 52 is open. At this time, the cavity of the ink supply chamber 30 is under positive pressure gas. Under the push of the positive pressure gas, the ink can flow more smoothly into the print head 200. The cavity of the ink return chamber 40 is under negative pressure gas. Under the pull of the negative pressure gas, the ink can flow back more smoothly, so that the ink circulates between the ink supply system 100 and the print head 200.

[0053] When the printhead 200 stops working or is powered off, the first valve 51 is connected to the buffer 60, or the negative pressure gas pipeline between the first valve 51, the second valve 52, and the buffer 60 is connected. The second valve 52 is closed, and then the negative pressure in the buffer 60 begins to balance the positive pressure in the ink supply chamber 30 to a certain negative pressure value. At this time, both the ink supply chamber 30 and the ink return chamber 40 are in a negative pressure state. The negative pressure holds the ink in place, preventing it from dripping from the printhead surface.

[0054] In this embodiment, the first valve 51 can be an electrically controlled valve such as a three-way solenoid valve. When a three-way solenoid valve is used, the first end of the three-way solenoid valve is connected to the air supply device 10, the second end of the three-way solenoid valve is connected to the ink supply chamber 30, and the third end of the three-way solenoid valve is connected to the buffer 60.

[0055] In this embodiment, the second valve 52 can be an electrically controlled valve such as a pressure-locking valve, and there is no limitation here.

[0056] To improve the accuracy of ink supply and further enhance printing quality, refer to Figure 2 In some embodiments, the ink supply system 100 may further include a positive pressure regulating valve 70 and a negative pressure regulating valve 80. The positive pressure regulating valve 70 is located on the positive pressure gas pipeline between the gas supply device 10 and the first valve 51, and the negative pressure regulating valve 80 is located on the negative pressure gas pipeline between the negative pressure pump 20 and the second valve 52.

[0057] In addition, to protect the working environment and ensure the clean gas extracted by the negative pressure pump 20, refer to... Figure 2 In some embodiments, the ink supply system 100 may further include a filter 90 connected to the negative pressure pump 20 to filter harmful substances or particulate matter in the exhaust gas.

[0058] Reference Figure 1 and Figure 2The present invention also proposes a digital printing device, which includes an ink supply system 100 and a print head 200. The ink supply system 100 and the print head 200 are cyclically connected. The specific structure of the ink supply system 100 is as described in the above embodiments. Since the digital printing device proposed in this invention includes all solutions of all embodiments of the ink supply system 100, it has at least the same technical effects as the ink supply system 100, which will not be described in detail here.

[0059] Reference Figures 1 to 3 The present invention also proposes an ink supply control method for an ink supply system 100. Based on the ink supply system 100 of the digital printing equipment described above, the ink supply control method includes the following steps:

[0060] S11. Upon receiving a shutdown signal or power failure signal, close the second valve 52;

[0061] S12. Connect the second and third interfaces of the first valve 51 and close its first interface to introduce gas from the negative pressure gas pipeline into the positive pressure gas pipeline and balance the gas in it to the target negative pressure value.

[0062] In this embodiment, the first valve 51 is a three-way solenoid valve, and the second valve 52 is a normally closed pressure-locking valve.

[0063] When the digital printing equipment suddenly loses power or stops working, the control system controls the locking valve to close, the second and third ports of the three-way solenoid valve are connected, the first port is closed, and then the negative pressure in the buffer 60 begins to balance the positive pressure in the ink supply chamber 30 to a certain negative pressure value. At this time, both the ink supply chamber 30 and the ink return chamber 40 are in a negative pressure state. The negative pressure holds the ink in place, ensuring that it does not drip from the surface of the print head 200.

[0064] Based on the above embodiments, referring to Figure 1 , Figure 2 and Figure 4 The ink supply control method may also include the following steps:

[0065] S21. Upon receiving the power-on signal, open the positive pressure regulating valve 70, and control the first port of the first valve 51 to connect with the second port and close its third port, so that positive pressure gas enters the ink supply chamber 30.

[0066] S21. Open the negative pressure regulating valve 80 and the second valve 52 to allow negative pressure gas to enter the ink return chamber 40 and allow ink to flow from the ink supply chamber 30 to the print head 200 and then back to the ink return chamber 40.

[0067] When the digital printing equipment is working normally, the compressed gas generated by the gas supply device 10 passes through the positive pressure regulating valve 70 and the three-way solenoid valve (at this time, the first interface and the second interface of the three-way solenoid valve are connected), and then enters the ink supply chamber 30. The gas in the ink return chamber 40 passes through the buffer 60 and the locking valve (at this time, the negative pressure regulating valve 80 needs to be controlled to open), and then passes through the negative pressure regulating valve 80 and is drawn by the negative pressure pump 20 to the required negative pressure value, so that the ink flows directly from the ink supply chamber 30 into the printhead, and then flows directly back from the printhead 200 to the ink return chamber 40.

[0068] The above description is merely an optional embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. An ink supply system for supplying ink to a print head, characterized by, The ink supply system comprises: a gas supply device; a negative pressure pump; an ink supply cavity, an air inlet end of which is communicated with the gas supply device through a positive pressure gas pipeline, and a liquid outlet end of which is adapted to communicate with a liquid inlet of the printing head; an ink return cavity, an air outlet end of which is communicated with the negative pressure pump through a negative pressure gas pipeline, and a liquid inlet end of which is adapted to communicate with a liquid outlet of the printing head; and an ink locking assembly arranged on the positive pressure gas pipeline and / or the negative pressure gas pipeline, for limiting the ink in the ink supply cavity and the ink return cavity from flowing into the printing head when the printing head stops working or is powered off; the ink locking assembly comprises a first valve arranged on the positive pressure gas pipeline and a second valve arranged on the negative pressure gas pipeline; the ink supply system further comprises a buffer arranged on the negative pressure gas pipeline and between the second valve and the ink return cavity, for stabilizing the gas pressure; when the printing head normally works, the first valve is not communicated with the negative pressure gas pipeline, and the second valve is opened; when the printing head stops working or is powered off, the first valve is communicated with the buffer, or the first valve is communicated with the negative pressure gas pipeline between the second valve and the buffer, and the second valve is closed.

2. The ink supply system of claim 1, wherein The first valve is a three-way electromagnetic valve, a first end of which is communicated with the gas supply device, a second end of which is communicated with the ink supply cavity, and a third end of which is communicated with the buffer.

3. The ink supply system of claim 1, wherein The second valve is a pressure locking valve.

4. The ink supply system of claim 1, wherein The ink supply system further comprises a positive pressure regulating valve arranged on the positive pressure gas pipeline between the gas supply device and the first valve.

5. The ink supply system of claim 1, wherein The ink supply system further comprises a negative pressure regulating valve arranged on the negative pressure gas pipeline between the negative pressure pump and the second valve.

6. The ink supply system according to any one of claims 1 to 5, wherein The ink supply system further comprises a filter communicated with the negative pressure pump.

7. A digital printing apparatus characterized by comprising: The ink supply system comprises: a printing head; and The ink supply system of any one of claims 1-6 is cyclically communicated with the printing head. The ink supply control method comprises the following steps:

8. An ink supply control method for an ink supply system according to any one of claims 1 to 6, characterized by when a stop signal or a power-off signal is received, the second valve is closed; the second interface of the first valve is controlled to be communicated with the third interface and the first interface thereof is closed, so that the gas in the negative pressure gas pipeline is communicated into the positive pressure gas pipeline and the gas therein is balanced to a target negative pressure value. The ink supply control method further comprises the following steps:

9. The ink supply control method of claim 8, wherein when a start signal is received, the positive pressure regulating valve is opened, and the first interface of the first valve is controlled to be communicated with the second interface and the third interface thereof is closed, so that the positive pressure gas enters into the ink supply cavity; the negative pressure regulating valve and the second valve are opened, so that the negative pressure gas enters into the ink return cavity, and the ink flows from the ink supply cavity to the printing head and then returns to the ink return cavity. ​

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