Electrofluid nozzle and electrofluid jet printing device

Abstract

The utility model discloses an electrofluid nozzle and an electrofluid jet printing device. Comprising a nozzle structure, a liquid supply module and a control module, the nozzle structure comprises an ink cavity and piezoelectric ceramics, an ink inlet end is arranged on the ink cavity, and a nozzle is arranged at the bottom of the ink cavity; the liquid supply module is connected with the ink inlet end and is used for providing negative pressure when the spray head structure is in a standby state, so that the meniscus at the nozzle is in a concave shape, and liquid is continuously supplied when the spray head structure is in a spraying state; the piezoelectric ceramic is embedded into the ink cavity wall at the back of the nozzle and is connected with the control module, the control module is used for controlling the piezoelectric ceramic to be opened or closed, and the piezoelectric ceramic is used for enabling the meniscus at the nozzle to be in a convex shape when the piezoelectric ceramic is opened. According to the utility model, ink can be prevented from flowing out of the nozzle and being excessively wetted when the nozzle is not used for jet printing, so that the electronic jet printing performance and reliability are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of inkjet printing, in particular to an electrofluid nozzle and an electrofluid printing device. Background Art

[0002] Electrofluidic printing is achieved by applying a high voltage between the nozzle and the substrate, causing the curved liquid surface at the nozzle to be deformed into a Taylor cone under the action of a strong electric field, and ejecting droplets much smaller than the nozzle from the tip of the cone.

[0003] The nozzle, as the outlet of ink droplets, determines the effect and quality of inkjet. Once the nozzle is damaged or clogged, the quality of printing will be seriously affected. Existing electrofluidic printheads will encounter problems of ink overflow or over-wetting at the nozzle when not printing, resulting in the inability to form a symmetrical Taylor cone during printing and slanted spraying. In severe cases, it may even lead to failure to spray or short circuit breakdown. Utility Model Content

[0004] The utility model provides an electrofluid spray head and an electrofluid spray printing device, which can prevent ink from flowing out of the nozzle and excessive wetting when the spray head is not spraying, thereby improving the electrofluid spray printing performance and reliability.

[0005] In the first aspect, the utility model provides an electrofluid nozzle, comprising: a nozzle structure, a liquid supply module and a control module; the nozzle structure comprises an ink chamber and a piezoelectric ceramic, the ink chamber is provided with an ink inlet end, and the bottom of the ink chamber is provided with a nozzle; the liquid supply module is connected to the ink inlet end, and is used to provide negative pressure when the nozzle structure is in a non-spraying state, so that the curved liquid surface at the nozzle is in a concave shape, and continuously supply liquid when the nozzle structure is in a spraying state; the piezoelectric ceramic is embedded in the ink chamber wall on the back of the nozzle, the piezoelectric ceramic is connected to the control module, the control module is used to control the opening or closing of the piezoelectric ceramic, and the piezoelectric ceramic is used to make the curved liquid surface at the nozzle in a convex shape when it is turned on.

[0006] Optionally, the piezoelectric ceramic includes a first input terminal and a second input terminal, the first input terminal is connected to the control module, and the second input terminal is grounded. When the control module outputs a high level, the piezoelectric ceramic is turned on, and when the control module outputs a low level, the piezoelectric ceramic is turned off.

[0007] Optionally, the nozzle structure includes a piezoelectric ceramic and at least two nozzles, and the piezoelectric ceramic is embedded in the ink chamber wall at the back of one of the nozzles.

[0008] Optionally, the nozzle structure includes at least two piezoelectric ceramics and at least two nozzles, and the piezoelectric ceramics are embedded in the ink chamber wall at the back of the nozzles in a one-to-one correspondence.

[0009] Optionally, a nozzle is provided at the bottom of the ink chamber, and the electrofluidic nozzle further includes a first control power supply, an extraction electrode and a control switch; the first control power supply or the ground terminal is connected to the extraction electrode through the control switch, and the first control power supply is used to apply a first voltage to the extraction electrode so that the electric field force on the curved liquid surface at the nozzle is smaller than the surface tension, thereby preventing injection; or, the electrofluidic nozzle further includes a second control power supply, and the first control power supply or the second control power supply is connected to the extraction electrode through the control switch, and the second control power supply is used to apply a second voltage to the extraction electrode so that the electric field force on the curved liquid surface at the nozzle is larger than the surface tension, thereby preventing injection; wherein the first voltage is greater than the second voltage.

[0010] Optionally, at least two nozzles are arranged on the bottom of the ink chamber, and the electrofluid nozzle also includes a first control power supply, extraction electrodes arranged one-to-one corresponding to the nozzles, and control switches connected one-to-one to the extraction electrodes; the first control power supply or the ground terminal is connected to each extraction electrode through the control switch corresponding to each extraction electrode, and the first control power supply is used to apply a first voltage to the extraction electrode so that the electric field force on the curved liquid surface at the nozzle is smaller than the surface tension, so that no injection occurs; or, the electrofluid nozzle also includes a second control power supply, and the first control power supply or the second control power supply is connected to each extraction electrode through the control switch corresponding to each extraction electrode; the second control power supply is used to apply a second voltage to the extraction electrode so that the electric field force on the curved liquid surface at the nozzle is larger than the surface tension, so that injection occurs; wherein the first voltage is greater than the second voltage.

[0011] Optionally, the electrofluid showerhead further comprises a substrate, and the substrate is arranged on a side of the extraction electrode away from the nozzle.

[0012] Optionally, the electrofluidic nozzle further includes a driving power supply, which is connected to the conductive layer in the ink chamber and is used to apply a first voltage to each nozzle.

[0013] Optionally, the liquid supply module includes an ink supply hose, a liquid storage bottle, a ventilation hose and an air pressure regulating unit which are connected in sequence; one end of the ink supply hose is connected to the ink inlet end, and the other end of the ink supply hose is inserted into the liquid storage bottle, and the liquid storage bottle is connected to the air pressure regulating unit through the ventilation hose.

[0014] In a second aspect, the utility model provides an electrofluidic printing device, including the electrofluidic nozzle provided by any embodiment of the utility model.

[0015] The electrofluid nozzle of the embodiment of the utility model includes a nozzle structure, a liquid supply module and a control module. The nozzle structure includes an ink chamber and a piezoelectric ceramic. The liquid supply module provides negative pressure in the standby state, so that the curved liquid surface at the nozzle is in a concave shape, which can avoid uncontrollable overflow of ink and excessive wetting of the nozzle, and at the same time avoid the deterioration of the ink due to long-term exposure. However, in the absence of a convex curved liquid surface, it is difficult for a strong electric field to suck out the ink and form a Taylor cone. Therefore, by setting a control module and piezoelectric ceramics, the control module controls the opening or closing of the piezoelectric ceramics, and when the piezoelectric ceramics are turned on, the curved liquid surface at the nozzle is in a convex shape, so that the nozzle is in a pre-injection state. In other words, the utility model can effectively protect the nozzle of the electrofluid nozzle when it is shut down, avoid the ink overflowing from the nozzle and drying up to cause nozzle clogging, thereby ensuring the life of the nozzle.

[0016] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present utility model, nor are they intended to limit the scope of the present utility model. Other features of the present utility model will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is a schematic diagram of the principle of an electric fluid nozzle in a standby state provided by an embodiment of the utility model;

[0019] Figure 2 This is a schematic diagram of the principle of an electric fluid nozzle in a pre-spraying state provided by an embodiment of the utility model;

[0020] Figure 3 This is a schematic diagram of the principle of an electric fluid nozzle in a spraying state provided by an embodiment of the utility model;

[0021] Figure 4 This is a schematic diagram of another type of electric fluid nozzle in a standby state provided by an embodiment of the utility model;

[0022] Figure 5 This is a schematic diagram of the principle of an array type electric fluid nozzle provided by an embodiment of the utility model;

[0023] Figure 6 This is a schematic diagram of the principle of another array type electric fluid nozzle provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0025] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0026] Figure 1 This is a schematic diagram of the principle of an electric fluid nozzle in a standby state provided by an embodiment of the utility model. Figure 2 This is a schematic diagram of the principle of an electric fluid nozzle in a pre-spraying state provided by an embodiment of the utility model. Figure 3 This is a schematic diagram of the principle of an electric fluid nozzle in a spraying state provided by an embodiment of the utility model, combined with Figure 1 , Figure 2 and Figure 3 The electrofluid nozzle comprises: a nozzle structure 1, a liquid supply module 2 and a control module 3.

[0027] The nozzle structure 1 includes an ink chamber 11 and a piezoelectric ceramic 12 . An ink inlet end is arranged on the ink chamber 11 , and a nozzle 110 is arranged on the bottom of the ink chamber 11 .

[0028] The liquid supply module 2 is connected to the ink inlet end, and is used to provide negative pressure when the nozzle structure 1 is in the standby state, so that the curved liquid surface at the nozzle 110 is in a concave shape, and continuously supply liquid when the nozzle structure 1 is in the spraying state.

[0029] The piezoelectric ceramic 12 is embedded in the ink chamber wall at the back of the nozzle 110. The piezoelectric ceramic 12 is connected to the control module 3. The control module 3 is used to control the opening or closing of the piezoelectric ceramic 12. The piezoelectric ceramic 12 is used to make the curved liquid surface at the nozzle 110 in a convex shape when it is turned on.

[0030] The functions of the liquid supply system of the liquid supply module 2 are as follows: first, to ensure that the curved liquid surface is in a concave shape when in the standby state; second, to ensure continuous liquid supply with stable back pressure during the injection process. It should be noted that no matter whether the electrofluid nozzle is in the standby state, the pre-injection state or the injection state, the back pressure at the ink inlet end is negative pressure. The embodiment of the utility model does not specifically limit the specific structure of the liquid supply module 2, as long as it can provide negative pressure and continuous liquid supply. Optionally, the liquid supply module 2 includes an ink supply hose, a liquid storage bottle, a ventilation hose and an air pressure regulating unit connected in sequence; one end of the ink supply hose is connected to the ink inlet end, and the other end of the ink supply hose is inserted into the liquid storage bottle, and the liquid storage bottle is connected to the air pressure regulating unit through the ventilation hose.

[0031] The control module 3 may include a microcontroller. Optionally, the control module 3 may include a single chip microcomputer, a digital signal processor (DSP) or a field programmable gate array (FPGA) for generating a TTL (Transistor-Transistor Logic) level signal.

[0032] The electrofluidic nozzle maintains a certain degree of negative pressure inside the ink chamber in the standby state. The negative pressure is used as the back pressure to form a curved liquid surface that is concave inwardly in the ink at the nozzle, thereby "lifting" the ink, which can prevent the ink from overflowing uncontrollably and over-wetting the nozzle, and at the same time prevent the ink from being exposed for a long time and deteriorating. However, if only negative pressure is used as the back pressure, the curved liquid surface at the nozzle is always in a concave state, and the electrofluidic nozzle cannot work normally. The reason is that in the absence of a convex curved liquid surface, it is difficult for a strong electric field to suck out the ink and form a Taylor cone. Therefore, when the electrofluidic nozzle is in the pre-injection state, it is necessary to turn on the piezoelectric ceramic 12 so that the piezoelectric ceramic bends into the ink chamber, thereby making the curved liquid surface at the nozzle 110 in a convex shape.

[0033] In some implementations, the piezoelectric ceramic 12 may be a long strip of piezoelectric ceramic, which may be mechanically coupled to the ink cavity wall through epoxy resin or other adhesives. The embodiment of the utility model can improve the reliability and integration of the electrofluid nozzle by embedding the piezoelectric ceramic 12 in the ink cavity wall at the back of the nozzle 110, and compared with other positions set on the ink cavity wall, the piezoelectric ceramic 12 is embedded in the ink cavity wall at the back of the nozzle 110, which is closer to the nozzle 110, and the deformation response of the curved liquid surface of the nozzle 110 is faster.

[0034] In some embodiments, the nozzle 110 may be a conical structure or a boss structure.

[0035] The electrofluid nozzle of the embodiment of the utility model includes a nozzle structure, a liquid supply module and a control module. The nozzle structure includes an ink chamber and a piezoelectric ceramic. The liquid supply module provides negative pressure in the standby state, so that the curved liquid surface at the nozzle is in a concave shape, which can avoid uncontrollable overflow of ink and excessive wetting of the nozzle, and at the same time avoid the deterioration of the ink due to long-term exposure. However, in the absence of a convex curved liquid surface, it is difficult for a strong electric field to suck out the ink and form a Taylor cone. Therefore, by setting a control module and piezoelectric ceramics, the control module controls the opening or closing of the piezoelectric ceramics, and when the piezoelectric ceramics are turned on, the curved liquid surface at the nozzle is in a convex shape, so that the nozzle is in a pre-injection state. In other words, the utility model can effectively protect the nozzle of the electrofluid nozzle when it is shut down, avoid the ink overflowing from the nozzle and drying up to cause nozzle clogging, thereby ensuring the life of the nozzle.

[0036] Optionally, the piezoelectric ceramic 12 includes a first input terminal and a second input terminal, the first input terminal is connected to the control module 3, the second input terminal is grounded, when the control module 3 outputs a high level, the piezoelectric ceramic 12 is turned on, and when the control module 3 outputs a low level, the piezoelectric ceramic 12 is turned off. At this time, the first input terminal is the positive electrode of the piezoelectric ceramic 12, and the second input terminal is the negative electrode of the piezoelectric ceramic 12.

[0037] Optionally, the piezoelectric ceramic 12 includes a first input terminal and a second input terminal, the first input terminal is connected to the first output terminal of the control module 3, and the second input terminal is connected to the second output terminal of the control module 3. When the absolute value of the voltage difference between the first output terminal of the control module 3 and the second output terminal is greater than a set threshold, the piezoelectric ceramic 12 is turned on, and when the voltage of the first output terminal of the control module 3 is equal to the voltage of the second output terminal, the piezoelectric ceramic 12 is turned off.

[0038] Continue to refer Figure 1 , Figure 2 and Figure 3 A nozzle 110 is arranged at the bottom of the ink chamber 11, and the electrofluid nozzle also includes a first control power supply 4, an extraction electrode 6 and a control switch 7.

[0039] The first control power supply 4 or the ground terminal is connected to the extraction electrode 6 through the control switch 7. The first control power supply 4 is used to apply a first voltage to the extraction electrode 6 so that the electric field force on the meniscus at the nozzle is smaller than the surface tension, so that no injection occurs. When the ground terminal is connected to the extraction electrode 6 through the control switch 7, the electric field force on the meniscus at the nozzle 110 is larger than the surface tension, so that injection occurs.

[0040] Figure 4 This is a schematic diagram of another type of electric fluid nozzle in a standby state provided by the embodiment of the utility model, referring to Figure 4In some embodiments, the electrofluidic nozzle further includes a second control power supply 5, the first control power supply 4 or the second control power supply 5 is connected to the extraction electrode 6 through a control switch 7, and the second control power supply 5 is used to apply a second voltage to the extraction electrode 6, so that the electric field force on the curved liquid surface at the nozzle 110 is greater than the surface tension, thereby causing the ejection; wherein the first voltage is greater than the second voltage. Exemplarily, the first voltage may be 1000V, and the second voltage may be 500V.

[0041] The first control power supply 4 and the second control power supply 5 can be high voltage signal generating devices, which can convert the input low voltage signal into a high voltage signal to generate a driving force. Exemplarily, the first control power supply 4 and the second control power supply 5 can select voltage generating devices such as a high voltage DC power supply, a voltage amplifier or a high voltage pulse power supply according to actual needs. The control switch 7 is responsible for receiving the printing data, controlling the different high voltages input by the first control power supply 4 and the second control power supply 5 to be connected to the extraction electrode 6, so as to adjust the electric field at the tip of the nozzle 110 and control the spraying behavior of the nozzle 110.

[0042] The extraction electrode 6 is made of conductive material and can be in the shape of a ring, a rectangle, etc., and is provided with leads and pins for convenient access to the control voltage. The closer the extraction electrode 6 is to the tip of the nozzle 110, the greater the effect of changing the voltage of the extraction electrode 6 on the electric field strength, and the better the control performance. In addition, the shape and size of the extraction electrode 6 can also be adjusted to enhance the performance of the extraction electrode 6 in regulating the electric field at the tip of the nozzle. Optionally, the control switch 7 is a single-pole double-throw switch.

[0043] The electrofluidic nozzle further includes a driving power source 8 , which is connected to the conductive layer 111 in the ink chamber 11 and is used to apply a first voltage to each nozzle 110 .

[0044] The electrofluid showerhead further comprises a substrate 9 , which is disposed on a side of the extraction electrode 6 away from the nozzle 110 .

[0045] by Figure 1 , Figure 2 and Figure 3 Taking the structure of the electric fluid nozzle shown in the figure as an example, the specific working principle of the electric fluid nozzle provided in this embodiment is as follows:

[0046] refer to Figure 1In the standby state, the control module 3 controls the piezoelectric ceramic 12 to be turned off, that is, the piezoelectric ceramic 12 is not applied with a driving voltage and is in a non-deformed state. The electrofluid nozzle maintains a certain degree of negative pressure inside its ink chamber 11, so that the curved liquid surface at the nozzle 110 is concave. The use of negative pressure can avoid uncontrollable overflow of ink and excessive wetting of the nozzle, while preventing the ink from being deteriorated due to long-term exposure. In the standby state, the electric field between the nozzle 110 and the extraction electrode 6 is zero or at a low value, wherein the extraction electrode 6 is connected to the first control power supply 4, and the voltage value of the first control power supply 4 can be set to be consistent with the voltage value of the driving power supply 8 or a value slightly lower than the driving power supply 8.

[0047] refer to Figure 2 When the electrofluid nozzle is in the pre-injection state or the injection state, the control module 3 controls the piezoelectric ceramic 12 to turn on, and the piezoelectric ceramic 12 bends into the ink chamber 11, driving the curved liquid surface at the nozzle 110 to be slightly convex. At this time, the voltage of the extraction electrode 6 has not yet switched to the ground terminal, so the nozzle 110 is in a non-injection state. The piezoelectric ceramic 12 has a fast response speed and can complete the deformation within a micron level, driving the shape of the curved liquid surface to change; the ink volume of the piezoelectric driven extrusion nozzle can be precisely controlled by adjusting the driving voltage to change the deformation of the piezoelectric ceramic 12, and the amount of convex ink can be accurately controlled within pL (10 12 The level of one-tenth of a liter is conducive to ensuring the repeatability of electrofluid printing.

[0048] refer to Figure 3 When the electrofluid nozzle is in the spraying state, the control module 3 continues to control the piezoelectric ceramic 12 to open, and the piezoelectric ceramic 12 keeps bending toward the ink chamber 11. The voltage of the extraction electrode 6 is switched to the ground terminal, and an electric field force sufficient to overcome the surface tension of the meniscus is formed between the extraction electrode 6 and the nozzle. Under the action of the electric field force, the meniscus forms a Taylor cone and sprays out droplets.

[0049] The present invention does not specifically limit the number of piezoelectric ceramics 12 and nozzles 110 of the nozzle structure 1, as long as the fluid nozzle can work normally. There can be only one piezoelectric ceramic 12 and one nozzle 110, such as Figures 1 to 4 There may also be a piezoelectric ceramic 12 and at least two nozzles 110, such as Figure 5 There may also be at least two piezoelectric ceramics 12 and at least two nozzles 110, such as Figure 6 shown.

[0050] Figure 5 Schematic diagram of the principle of an array type electrofluid nozzle provided by the embodiment of the utility model, such as Figure 5 As shown, the nozzle structure 1 includes a piezoelectric ceramic 12 and at least two nozzles 110 , and the piezoelectric ceramic 12 is embedded in the ink chamber wall at the back of one of the nozzles 110 .

[0051] Figure 6 Schematic diagram of another array type electrofluid nozzle provided by the embodiment of the utility model, such as Figure 6 As shown, in some embodiments, the nozzle structure 1 includes at least two piezoelectric ceramics 12 and at least two nozzles 110 , and the piezoelectric ceramics 12 are embedded in the ink chamber wall at the back of the nozzles 110 in a one-to-one correspondence.

[0052] That is to say, the piezoelectric ceramic 12 can be driven to control the meniscus of the nozzle 110 in a one-to-many or one-to-one manner. Specifically, in the one-to-many manner, a larger piezoelectric ceramic is placed on the ink cavity wall behind one of the nozzles 110, and the deformation of the piezoelectric ceramic 12 can control the meniscus of all the nozzles 110; in the one-to-one manner, the ink cavity wall behind each nozzle 110 corresponds to one piezoelectric ceramic 12. For highly integrated array-type nozzles, the piezoelectric ceramic 12 can be manufactured using a MEMS (Micro-Electro-Mechanical System) process.

[0053] Combination Figure 5 and Figure 6 At least two nozzles 110 are arranged at the bottom of the ink chamber 11, and the electrofluid nozzle also includes a first control power supply 4, extraction electrodes 6 arranged one-to-one corresponding to the nozzles 110, and a control switch 7 connected to the extraction electrodes 6 one-to-one correspondingly.

[0054] The first control power supply 4 or the ground terminal is connected to each extraction electrode 6 through a control switch 7 corresponding to each extraction electrode 6. The first control power supply 4 is used to apply a first voltage to the extraction electrode so that the electric field force on the meniscus at the nozzle is smaller than the surface tension, so that no injection occurs. When the ground terminal is connected to the extraction electrode 6 through the control switch 7, the electric field force on the meniscus at the nozzle 110 is larger than the surface tension, so that injection occurs.

[0055] Alternatively, the electrofluid nozzle also includes a second control power supply 5, and the first control power supply 4 or the second control power supply 5 is connected to each extraction electrode 6 through a control switch 7 corresponding to each extraction electrode 6, and the second control power supply 5 is used to apply a second voltage to the extraction electrode 6 so that the electric field force applied to the curved liquid surface at the nozzle 110 is greater than the surface tension, thereby causing spraying; wherein the first voltage is greater than the second voltage.

[0056] Optionally, the nozzle 110 is a conical structure, and the center of each nozzle 110 is collinear with the center of the through hole of each extraction electrode 6 .

[0057] Optionally, the extraction electrode 6 is made of conductive material and may be in a circular ring, rectangular, or other shape. The extraction electrodes 6 of different nozzles 110 should be insulated to avoid electrical crosstalk leading to control failure.

[0058] The at least two nozzles 110 include a first nozzle 10, a second nozzle 20 and a third nozzle 30. The spraying state of each nozzle 110 is controlled by the voltage of the extraction electrode 6, thereby controlling the independent spraying of each nozzle. Figure 5 As shown, the control module 3 controls the piezoelectric ceramic 12 to turn on, and the piezoelectric ceramic 12 bends into the ink chamber 11, driving the curved liquid surface at the nozzle 110 to be slightly convex. At this time, the voltage of the extraction electrode 6 corresponding to the third nozzle 30 has not yet switched to the ground terminal, so the third nozzle 30 is in a pre-injection state. The voltage of the extraction electrode 6 corresponding to the first nozzle 10 and the second nozzle 20 is switched to the ground terminal, and an electric field force sufficient to overcome the surface tension of the curved liquid surface is formed between the extraction electrode 6 corresponding to the first nozzle 10 and the second nozzle 20 and the nozzle. The curved liquid surface forms a Taylor cone under the action of the electric field force and ejects droplets, that is, the first nozzle 10 and the second nozzle 20 are in a pre-injection state.

[0059] Based on the same utility model concept, the utility model embodiment also provides an electrofluidic printing device, which includes the electrofluidic nozzle of any of the above embodiments and has corresponding functional modules and beneficial effects of the electrofluidic nozzle.

[0060] The above specific implementations do not constitute a limitation on the protection scope of the present utility model. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. An electrofluid nozzle, characterized in that: include: Nozzle structure, liquid supply module and control module; The nozzle structure includes an ink chamber and piezoelectric ceramics, the ink chamber is provided with an ink inlet end, and the bottom of the ink chamber is provided with a nozzle; The liquid supply module is connected to the ink inlet end and is used to provide negative pressure when the nozzle structure is in a standby state, so that the meniscus at the nozzle is in a concave shape, and continuously supply liquid when the nozzle structure is in a spraying state; The piezoelectric ceramic is embedded in the ink chamber wall at the back of the nozzle. The piezoelectric ceramic is connected to the control module. The control module is used to control the opening or closing of the piezoelectric ceramic. The piezoelectric ceramic is used to make the curved liquid surface at the nozzle in a convex shape when it is turned on.

2. The electrofluidic nozzle according to claim 1, characterized in that: The piezoelectric ceramic includes a first input end and a second input end, the first input end is connected to the control module, the second input end is grounded, when the control module outputs a high level, the piezoelectric ceramic is turned on, when the control module outputs a low level, the piezoelectric ceramic is turned off.

3. The electrofluidic nozzle according to claim 1, characterized in that: The nozzle structure includes a piezoelectric ceramic and at least two nozzles, and the piezoelectric ceramic is embedded in the ink chamber wall at the back of one of the nozzles.

4. The electrofluidic nozzle according to claim 1, characterized in that: The nozzle structure includes at least two piezoelectric ceramics and at least two nozzles, and the piezoelectric ceramics are embedded in the ink cavity wall at the back of the nozzle in a one-to-one correspondence.

5. The electrofluidic nozzle according to claim 1, characterized in that: A nozzle is arranged on the bottom of the ink chamber, and the electrofluid nozzle also includes a first control power supply, an extraction electrode and a control switch; The first control power supply or ground terminal is connected to the extraction electrode through the control switch, and the first control power supply is used to apply a first voltage to the extraction electrode so that the electric field force on the meniscus at the nozzle is smaller than the surface tension, so that no spraying occurs; Alternatively, the electrofluid nozzle also includes a second control power supply, the first control power supply or the second control power supply is connected to the extraction electrode through the control switch, and the second control power supply is used to apply a second voltage to the extraction electrode so that the electric field force applied to the curved liquid surface at the nozzle is greater than the surface tension, thereby causing spraying; wherein the first voltage is greater than the second voltage.

6. The electrofluidic nozzle according to claim 1, characterized in that: At least two nozzles are arranged on the bottom of the ink chamber, and the electrofluid nozzle further comprises a first control power supply, extraction electrodes arranged one-to-one corresponding to the nozzles, and a control switch connected one-to-one corresponding to the extraction electrodes; The first control power supply or ground terminal is connected to each of the extraction electrodes through the control switch corresponding to each of the extraction electrodes, and the first control power supply is used to apply a first voltage to the extraction electrode so that the electric field force on the curved liquid surface at the nozzle is smaller than the surface tension, so that no spraying occurs; Alternatively, the electrofluidic nozzle further comprises a second control power supply, and the first control power supply or the second control power supply is connected to each of the extraction electrodes through the control switch corresponding to each of the extraction electrodes; The second control power supply is used to apply a second voltage to the extraction electrode so that the electric field force on the curved liquid surface at the nozzle is greater than the surface tension, thereby causing spraying; wherein the first voltage is greater than the second voltage.

7. The electrofluidic nozzle according to claim 5 or 6, characterized in that: The device also includes a substrate, which is arranged on a side of the extraction electrode away from the nozzle.

8. The electrofluidic nozzle according to claim 1, characterized in that: It also includes a driving power supply, which is connected to the conductive layer in the ink chamber and is used to apply a first voltage to each of the nozzles.

9. The electrofluidic nozzle according to claim 1, characterized in that: The liquid supply module comprises an ink supply hose, a liquid storage bottle, a ventilation hose and an air pressure regulating unit which are connected in sequence; One end of the ink supply hose is connected to the ink inlet end, and the other end of the ink supply hose is inserted into the liquid storage bottle. The liquid storage bottle is connected to the air pressure regulating unit through the ventilation hose.

10. An electro-fluid printing device, characterized in that: The invention comprises an electrofluid nozzle as described in any one of claims 1 to 9.

Images