Printing head

Abstract

The invention discloses a printing head. Comprising a liquid storage component for storing ink, a driving component and a spraying hole component, the driving component and the spraying hole component are located on the two sides of the liquid storage component respectively, and the driving component can enable the ink in the liquid storage component to be sprayed out of the spraying hole component; the driving component comprises piezoelectric ceramics; the piezoelectric ceramic is provided with an isolation part which isolates the piezoelectric ceramic to be matched with the liquid storage component.

Description

Technical Field

[0001] The present application relates to the field of inkjet printing, and in particular to a print head. Background Art

[0002] Drop-on-demand piezoelectric printheads are widely used to print on a variety of substrates. When using jettable materials such as UV curable printing inks, piezoelectric printheads are advantageous compared to thermal inkjet printheads, whose higher viscosity or chemical composition prevents thermal inkjet from being used for its DOD applications. Thermal inkjet printheads use a heating element actuator in the ink filling chamber to vaporize the ink and generate bubbles that force the ink to drip from the nozzle. Therefore, the jettable materials suitable for use in thermal inkjet printheads are limited to those materials whose composition can withstand boiling point temperatures without mechanical or chemical degradation. However, piezoelectric printheads can adapt to a wider selection of jettable materials because they use piezoelectric material actuators on the membrane of the ink filling chamber to generate pressure pulses that force the ink to drip from the nozzle.

[0003] However, one problem with piezoelectric print heads is mechanical crosstalk between adjacent nozzles. When the membrane in a given nozzle moves upward, the membrane in an adjacent nozzle moves downward by a certain smaller distance. This negatively affects the operation of adjacent nozzles. Ideally, when a given nozzle is actuated (moving its membrane up or down), the membrane in an adjacent nozzle will not be affected. More precisely, the membranes in adjacent nozzles will be completely independent and will not detectably move when an adjacent nozzle is actuated and its membrane moves. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the present application provides a print head.

[0005] In the present application, the print head ejects ink droplets downwards to perform printing, so the direction in which the ink is ejected is defined as downwards, and the opposite direction is defined as upwards.

[0006] The specific technical solutions of this application are as follows:

[0007] 1. A print head, comprising a liquid storage member for storing ink, a driving member and a nozzle member, wherein the driving member and the nozzle member are respectively located on both sides of the liquid storage member, and the driving member can cause the ink in the liquid storage member to be ejected from the nozzle member;

[0008] The driving member includes a piezoelectric ceramic; an isolating portion is provided on the piezoelectric ceramic to isolate the piezoelectric ceramic to be compatible with the liquid storage member;

[0009] Preferably, the isolation portion is an isolation groove opened on the piezoelectric ceramic.

[0010] 2. The print head according to item 1, wherein the liquid storage member comprises a plurality of mutually independent pressure chambers, the ink is stored in the pressure chambers, the piezoelectric ceramic covers one end of the pressure chambers; and the isolation groove is opened between two adjacent pressure chambers;

[0011] Preferably, the liquid storage member includes a cavity wall forming a pressure cavity, the cavity wall is provided with a plurality of cavities, the cavity wall is connected to the piezoelectric ceramic, and the isolation groove is correspondingly opened at the connection between the cavity wall and the piezoelectric ceramic;

[0012] Further preferably, the piezoelectric ceramic includes a vibration area corresponding to the pressure cavity, the vibration area is located at one end of the pressure cavity and seals the pressure cavity, and the isolation groove is opened between two adjacent vibration areas.

[0013] 3. The print head according to item 2, wherein, preferably, the depth of the isolation groove is 10% to 80% of the thickness of the piezoelectric ceramic;

[0014] Preferably, the depth of the isolation groove is 20% to 60% of the thickness of the piezoelectric ceramic;

[0015] Further preferably, the depth of the isolation groove is 40% to 50% of the thickness of the piezoelectric ceramic.

[0016] 4. The print head according to item 2, wherein the isolation groove is opened on a side of the piezoelectric ceramic close to the liquid storage member;

[0017] Alternatively, the isolation groove is opened on a side of the piezoelectric ceramic facing away from the liquid storage member.

[0018] 5. The print head according to any one of items 1 to 4, wherein the isolation groove is filled with an isolation agent;

[0019] Preferably, a first adhesive layer is provided between the driving member and the liquid storage member;

[0020] More preferably, the first adhesive layer and the filler are made of the same material.

[0021] 6. The print head according to any one of items 1 to 5, wherein the liquid storage member comprises a cavity wall, and the material of the cavity wall is metal;

[0022] Preferably, the cavity wall is made of stainless steel or aluminum alloy.

[0023] 7. The print head according to item 6, wherein a protective layer is provided on the cavity wall;

[0024] Preferably, the protective layer is an aluminum alloy layer;

[0025] Further preferably, the protective layer is an aluminum oxide layer;

[0026] Further preferably, when the cavity wall is made of aluminum alloy, the protective layer is an aluminum alloy layer.

[0027] 8. The print head according to item 6, wherein a protective layer is provided on the cavity wall;

[0028] Preferably, the protective layer is a nitride layer;

[0029] Further preferably, the protective layer is an iron nitride layer;

[0030] Further preferably, the protective layer is a nitrided stainless steel layer;

[0031] Further preferably, when the cavity wall is made of stainless steel, the protective layer is a nitride layer.

[0032] 9. The print head according to any one of items 1 to 8, wherein the nozzle hole member comprises a nozzle hole layer, and a plurality of nozzle holes corresponding to the liquid storage member are formed on the nozzle hole layer;

[0033] Preferably, the spray hole layer is made of metal;

[0034] Further preferably, the spray hole layer is made of stainless steel or nickel alloy;

[0035] 10. The print head according to item 9, wherein a second adhesive layer is provided between the nozzle member and the liquid storage member; the second adhesive layer is used for connecting the nozzle member and the liquid storage member;

[0036] Preferably, the second adhesive layer is arranged between the orifice layer and the cavity wall;

[0037] Further preferably, the second adhesive layer covers the orifice layer;

[0038] Further preferably, the second adhesive layer is an adhesive film, an epoxy layer, or an acrylic layer.

[0039] Beneficial Effects

[0040] The present application provides a print head, which reduces mechanical crosstalk on piezoelectric ceramics by opening an isolation groove on the piezoelectric ceramics, making the ink ejected by the print head more accurate, thereby improving the quality of the printed matter. In addition, the print head in the present application reasonably sets the positions of various components and uses a specific connection method, so that the entire print head can be made of metal material, thereby improving the wear resistance of the print head and increasing the service life of the print head.

[0041] The print head provided by the present application reduces the mechanical crosstalk when the piezoelectric ceramic vibrates due to the isolation structure. This reduces the influence of adjacent vibration intervals when the print head prints at a high frequency, thereby enabling the print head to print at a higher frequency. The ignition frequency of the nozzle is increased, and the frequency of stable operation of the nozzle is significantly improved. Furthermore, a higher ignition frequency can eject more ink in the same time, increase the printing speed of the print head, and thus increase the printing efficiency of the print head. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a schematic structural diagram of an embodiment of a print head in the present application;

[0043] Figure 2 is a schematic structural diagram of another embodiment of a print head in the present application;

[0044] Figure 3 It is a line graph of data changes in Examples 1 to 4 of the present application and the comparative example.

[0045] In the figure, 1, piezoelectric ceramic; 11, isolation groove; 12, electrode; 13, first adhesive layer; 2, liquid storage component; 21, pressure chamber; 22, chamber wall; 3, nozzle component; 31, nozzle layer; 32, nozzle; 33, second adhesive layer. DETAILED DESCRIPTION

[0046] The present application is described in detail below. Although specific embodiments of the present application are shown, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0047] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the functional differences of components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" are open-ended terms and should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present application, but the description is based on the general principles of the specification and is not intended to limit the scope of the present application. The scope of protection of the present application shall be determined by the attached claims.

[0048] refer to Figure 1The present application provides a print head. It includes a liquid storage component 2 for storing ink, a driving component and a nozzle component 3, wherein the driving component and the nozzle component 3 are respectively located on both sides of the liquid storage component 2, and the driving component can make the ink in the liquid storage component 2 spray out from the nozzle component 3;

[0049] The liquid storage member 2 is used to store ink, and the driving member is a power source. When printing, the driving member can generate power to drive the ink droplets in the liquid storage member 2 to be ejected. The nozzle member 3 is used to provide a channel for the ink to pass through, and the ink can be ejected through the nozzle member 3.

[0050] The driving member includes a piezoelectric ceramic 1 ; an isolating portion is provided on the piezoelectric ceramic 1 to isolate the piezoelectric ceramic 1 to be compatible with the liquid storage member 2 .

[0051] The piezoelectric ceramic 1 is laid on the liquid storage member 2, and the piezoelectric ceramic 1 is an integrated structure. By setting a local drive on the piezoelectric ceramic 1, the local vibration of the piezoelectric ceramic 1 is realized. Therefore, when the piezoelectric ceramic 1 generates a driving force, the adjacent piezoelectric ceramics 1 will be subject to mechanical crosstalk. As a result, the vibration amplitude of the piezoelectric ceramic 1 is affected, and further, the accuracy of the print head is affected.

[0052] Therefore, an isolation part is provided on the piezoelectric ceramic 1 of the present application, and the isolation part is used to isolate the vibration area of ​​the piezoelectric ceramic 1, thereby reducing the mechanical crosstalk of the piezoelectric ceramic 1, thereby improving the vibration accuracy of the piezoelectric ceramic 1, and improving the printing quality and printing accuracy of the print head. On the one hand, the isolation part can mechanically isolate the vibration area of ​​the piezoelectric ceramic 1, and on the other hand, the piezoelectric ceramic 1 also needs to maintain a certain mechanical strength at the position of the isolation part, reduce the sealing of the piezoelectric ceramic 1 to the liquid storage member 2, and maintain the vibration strength and vibration stability of the piezoelectric ceramic 1. Therefore, the isolation part must not only isolate the piezoelectric ceramic 1 from mechanical crosstalk, but also ensure the connection strength between the various vibration areas of the piezoelectric ceramic 1.

[0053] The isolation part reduces the mechanical crosstalk when the piezoelectric ceramic 1 vibrates. This reduces the vibration effect of the adjacent area of ​​the piezoelectric ceramic 1 during printing, so that the piezoelectric ceramic 1 can be stably printed at a high frequency, and the ignition frequency of the piezoelectric ceramic 1 is increased, thereby improving the printing efficiency. Furthermore, a higher ignition frequency can eject more ink in the same time, increase the printing speed of the print head, and further significantly improve the printing efficiency of the print head.

[0054] The liquid storage component 2 includes a plurality of independent pressure chambers 21 in which ink is stored, and the piezoelectric ceramic 1 covers one end of the pressure chamber 21 ; the nozzle component 3 includes a nozzle layer 31 on which a plurality of nozzles 32 corresponding to the liquid storage component 2 are provided.

[0055] The piezoelectric ceramic 1 can generate power and vibrate when powered, and then the piezoelectric ceramic 1 squeezes the ink droplets in the liquid storage member 2 so that the ink droplets in the liquid storage member 2 are ejected from the nozzle member 3 .

[0056] In a specific embodiment, the piezoelectric ceramic 1 is an integrally formed structure, and the piezoelectric ceramic 1 covers all the pressure chambers 21 inside the liquid storage member 2 .

[0057] In a specific embodiment, an electrode 12 is disposed on the piezoelectric ceramic 1 , and the electrode 12 includes a plurality of branch electrodes 12 disposed on the piezoelectric ceramic 1 ; by supplying electricity to the branch electrodes 12 , the piezoelectric ceramic 1 can be driven to vibrate.

[0058] In the present application, since the piezoelectric ceramic 1 is integrally formed, the branch electrodes 12 are used for conducting electricity. Therefore, when the piezoelectric ceramic 1 vibrates, the adjacent areas will be affected by the crosstalk of the mechanical vibration.

[0059] Therefore, by placing the isolation portion between the vibration regions of the piezoelectric ceramic 1 , the branch electrodes 12 can reduce the mechanical vibration crosstalk to the adjacent regions when driving the piezoelectric ceramic 1 to vibrate locally.

[0060] In a specific embodiment, the isolation portion is an isolation groove 11 opened on the piezoelectric ceramic 1 .

[0061] The isolation groove 11 is a position opened between the vibration areas on the piezoelectric ceramic 1. The isolation groove 11 is a groove structure, and the isolation groove 11 is a structure that does not penetrate the piezoelectric ceramic 1. Therefore, at the position of the isolation groove 11, the piezoelectric ceramics 1 are still connected. At the same time, the isolation groove 11 removes the piezoelectric ceramic 1, thereby making the piezoelectric ceramic 1 a local cavity structure. Therefore, when the piezoelectric ceramics 1 at the positions on both sides of the isolation groove 11 vibrate, the mechanical vibration generated by it will be difficult to be transmitted through the isolation groove 11, thereby reducing the mechanical crosstalk between the vibration areas of the piezoelectric ceramic 1. In addition, when the piezoelectric ceramic 1 is driven to vibrate, the crosstalk between adjacent vibration areas can be reduced, thereby improving the accuracy of the piezoelectric ceramic 1 when driving the liquid in the liquid storage member 2. This improves the printing accuracy of the print head.

[0062] The isolation groove 11 is opened between two adjacent pressure chambers 21;

[0063] Preferably, the liquid storage member 2 includes a cavity wall 22 forming a pressure cavity 21, a plurality of cavity walls 22 are provided, the cavity wall 22 is connected to the piezoelectric ceramic 1, and the isolation groove 11 is correspondingly opened at the connection between the cavity wall 22 and the piezoelectric ceramic 1;

[0064] Further preferably, the piezoelectric ceramic 1 includes a vibration zone corresponding to the pressure chamber 21 , the vibration zone is located at one end of the pressure chamber 21 and seals the pressure chamber 21 , and the isolation groove 11 is provided between two adjacent vibration zones.

[0065] When the piezoelectric ceramic 1 is connected to the liquid storage member 2, the piezoelectric ceramic 1 is in direct contact with the end surface of the cavity wall 22 of the liquid storage member 2 and is fixedly connected, thereby realizing a fixed connection between the liquid storage member 2 and the piezoelectric ceramic 1. At the same time, the connection between the piezoelectric ceramic 1 and the cavity wall 22 also seals the pressure cavity 21, thereby reducing the leakage of ink in the pressure cavity 21.

[0066] The vibration area of ​​the piezoelectric ceramic 1 corresponds to the pressure chamber 21 of the liquid storage member 2. Therefore, when the vibration area of ​​the piezoelectric ceramic 1 vibrates, it will squeeze the inner space of the pressure chamber 21 and squeeze out the ink in the pressure chamber 21.

[0067] The position where the piezoelectric ceramic 1 is connected to the cavity wall 22 of the liquid storage member 2 is the connection area. The isolation groove 11 is opened in the connection area. The width of the connection area corresponds to the thickness of the cavity wall 22. The width of the isolation groove 11 is related to the setting. Those skilled in the art can determine the width of the isolation groove 11 based on the crosstalk strength of the piezoelectric ceramic 1 when in use, the specific use environment of the print head, and the difficulty, strength and cost of the print head processing technology. Therefore, it will not be repeated here.

[0068] In the present application, the ink is located in the liquid storage member 2, and therefore, with the pressure chamber 21 as a reference, the position close to the center of the pressure chamber 21 is referred to as the inside, and the position relatively far from the pressure chamber 21 is referred to as the outside.

[0069] The isolation groove 11 can be opened on the inner side or the outer side of the connection area.

[0070] In a specific embodiment, the isolation groove 11 is opened on the side of the piezoelectric ceramic 1 facing away from the liquid storage member 2 .

[0071] That is, the isolation groove 11 is opened outside the connection area of ​​the piezoelectric ceramic 1 .

[0072] Therefore, the piezoelectric ceramic 1 is an integral structure at the inner side, and when the piezoelectric ceramic 1 is connected to the cavity wall 22, it is also in contact with the cavity wall 22 as an integral structure. Therefore, although the isolation groove 11 is provided on the piezoelectric ceramic 1, it does not affect the connection strength between the piezoelectric ceramic 1 and the cavity wall 22. The piezoelectric ceramic 1 can seal the pressure cavity 21, and the piezoelectric ceramic 1 is difficult to separate from the cavity wall 22. Therefore, the isolation groove 11 can reduce the mechanical crosstalk of the piezoelectric ceramic 1 while ensuring the connection stability between the piezoelectric ceramic 1 and the cavity wall 22, thereby improving the vibration accuracy of the piezoelectric ceramic 1 and improving the printing quality of the print head.

[0073] The depth of the isolation groove 11 is 10% to 80% of the thickness of the piezoelectric ceramic 1;

[0074] Preferably, the depth of the isolation groove 11 is 20% to 60% of the thickness of the piezoelectric ceramic 1;

[0075] More preferably, the depth of the isolation groove 11 is 40% to 50% of the thickness of the piezoelectric ceramic 1 .

[0076] The depth of the isolation groove 11 is 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80% of the thickness of the piezoelectric ceramic 1 .

[0077] In a specific embodiment, the isolation groove 11 is opened on a side of the piezoelectric ceramic 1 close to the liquid storage member 2 .

[0078] That is, the isolation groove 11 is opened on the inner side of the connection area of ​​the piezoelectric ceramic 1 .

[0079] Since the inner side of the piezoelectric ceramic 1 is connected to the cavity wall 22 , it is necessary to first open the isolation groove 11 on the inner side of the piezoelectric ceramic 1 , and then connect and fix the piezoelectric ceramic 1 to the cavity wall 22 .

[0080] In a specific embodiment, the isolation groove 11 is opened inside the piezoelectric ceramic 1 , and the width of the isolation groove 11 is smaller than the width of the connection area, so that the connection area can be connected to the cavity wall 22 , and the isolation groove 11 is located between the piezoelectric ceramic 1 and the cavity wall 22 .

[0081] In another specific embodiment, the isolation groove 11 is filled with an isolation agent;

[0082] The isolation groove 11 is also opened on the inner side of the piezoelectric ceramic 1 , and the width of the isolation groove 11 is equal to or smaller than the width of the connection region. The isolation groove 11 is filled with a filler separated from the piezoelectric ceramic 1 .

[0083] When the isolation groove 11 is arranged inside the piezoelectric ceramic 1, the piezoelectric ceramic 1 is connected to the cavity wall 22; the pressure chamber 21 is located between the cavity wall 22 and the piezoelectric ceramic 1. At this time, the use of fillers can strengthen the connection strength between the piezoelectric ceramic 1 and the cavity wall 22. At the same time, the filler can also seal the piezoelectric ceramic 1, increase the connection sealing between the piezoelectric ceramic 1 and the cavity wall 22, and reduce the leakage of ink in the pressure chamber 21. Furthermore, the filler can also strengthen the strength of the piezoelectric ceramic 1. When the piezoelectric ceramic 1 vibrates, the filler can absorb the vibration kinetic energy of the piezoelectric ceramic 1 and the mechanical crosstalk between the vibration zones. It can also share the position of the piezoelectric ceramic 1 relative to the cavity wall 22 when it vibrates, thereby reducing the relative displacement amplitude between the piezoelectric ceramic 1 and the cavity wall 22, and thereby increasing the connection strength between the piezoelectric ceramic 1 and the cavity wall 22. Improve the service life of the print head.

[0084] The depth of the isolation groove 11 is 10% to 80% of the thickness of the piezoelectric ceramic 1;

[0085] Preferably, the depth of the isolation groove 11 is 20% to 60% of the thickness of the piezoelectric ceramic 1;

[0086] More preferably, the depth of the isolation groove 11 is 40% to 50% of the thickness of the piezoelectric ceramic 1 .

[0087] The depth of the isolation groove 11 is 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80% of the thickness of the piezoelectric ceramic 1 .

[0088] Preferably, a first adhesive layer 13 is provided between the driving member and the liquid storage member 2;

[0089] More preferably, the first adhesive layer 13 and the filler are made of the same material.

[0090] On the one hand, the first adhesive layer 13 can be used to connect the piezoelectric ceramic 1 and the liquid storage member 2, so that the piezoelectric ceramic 1 and the liquid storage member 2 are connected and sealed. On the other hand, the first adhesive layer 13 and the filler are made of the same material, so that when the piezoelectric ceramic 1 is connected to the cavity wall 22, the first adhesive layer 13 and the filler can be installed at the same time, reducing the processing steps of the filler and the first adhesive layer 13, simplifying the manufacturing steps of the filler and the first adhesive layer 13, and thus reducing the processing cost of the print head.

[0091] The liquid storage member 2 includes a cavity wall 22, and the cavity wall 22 is made of metal;

[0092] Preferably, the cavity wall 22 is made of stainless steel or aluminum alloy;

[0093] Preferably, the spray hole layer 31 is made of metal;

[0094] Further preferably, the spray hole layer 31 is made of stainless steel or nickel alloy;

[0095] A protective layer is provided on the cavity wall 22;

[0096] Preferably, the protective layer is an aluminum alloy layer or a nitride layer;

[0097] Further preferably, the protective layer is an aluminum oxide layer, an iron nitride layer, or a carburized stainless steel layer.

[0098] The liquid storage component 2 and the nozzle layer 31 are both set as metal components to improve the strength and wear resistance of the liquid storage component 2 and the nozzle layer 31, so that the manufactured print head has higher strength and improves the drop resistance of the print head. It can not only reduce the transportation safety of the print head and reduce the possibility of failure of the print head during transportation, but also increase the service life of the print head.

[0099] The ink is located in the pressure chamber 21, so the ink is in direct contact with the chamber wall 22. Different inks have different properties, and the ink is a liquid that is in direct contact with the chamber wall 22. Therefore, a protective layer is provided to further protect the chamber wall 22, thereby reducing the possibility of corrosion or impact damage to the chamber wall 22 caused by the ink.

[0100] In a specific embodiment, the cavity wall 22 is made of stainless steel, the spray hole layer 31 is made of stainless steel, and the protective layer is an iron nitride layer or a nitrided stainless steel layer.

[0101] The cavity wall 22 and the spray hole layer 31 of the liquid storage member 2 are both made of stainless steel, which reduces the possibility of electrochemical reaction between the spray hole layer 31 and the cavity wall 22. In addition, the spray hole layer 31 and the cavity wall 22 made of consistent materials can reduce the manufacturing cost and difficulty of manufacturing.

[0102] In a specific embodiment, the cavity wall 22 is nitrided to form a dense iron nitride or nitrided stainless steel layer on the surface of the cavity wall 22 made of stainless steel, thereby improving the corrosion resistance and hardness of the cavity wall 22. The service life of the print head is improved. Furthermore, the nitrided layer makes the surface of the cavity wall 22 smoother and has a certain non-stickiness, reducing the adhesion of ink on the cavity wall, thereby allowing the ink to be discharged from the cavity wall more smoothly. The resistance of the ink flow during printing is reduced, and the printing efficiency is improved.

[0103] In another specific embodiment, the cavity wall is made of aluminum alloy, and the protective layer is an aluminum oxide layer.

[0104] The passivated aluminum alloy is more stable and corrosion-resistant than stainless steel. Therefore, the cavity wall 22 is made of aluminum alloy, thereby increasing the service life of the cavity wall 22. On the other hand, the aluminum alloy cavity wall 22 is protected by an aluminum oxide layer, thereby further reducing the damage of ink to the cavity wall 22, thereby increasing the service life of the cavity wall 22.

[0105] The aluminum oxide structure has low manufacturing strength, is easy to process, and the aluminum oxide layer has low manufacturing cost and excellent corrosion resistance stability. In addition, aluminum oxide has extremely high density and can provide strict protection for the cavity wall 22. Therefore, the aluminum oxide layer is used to protect the cavity wall 22.

[0106] A second adhesive layer 33 is provided between the spray hole member 3 and the liquid storage member 2; the second adhesive layer 33 is used to connect the spray hole member 3 and the liquid storage member 2;

[0107] Preferably, the second adhesive layer 33 is disposed between the orifice layer 31 and the cavity wall 22;

[0108] Further preferably, the second adhesive layer 33 covers the orifice layer 32;

[0109] More preferably, the second adhesive layer 33 is an adhesive film, an epoxy layer, or an acrylic layer.

[0110] The nozzle member 3 is provided with a nozzle hole 32 , and the ink in the liquid storage member 2 is sprayed out from the nozzle hole 32 .

[0111] The second adhesive layer 33 is used to connect the orifice layer 31 with the liquid storage member 2 ; at the same time, the second adhesive layer 33 can also seal the orifice layer 31 with the cavity wall 22 , reducing the possibility of ink leakage from the orifice layer 31 .

[0112] The second adhesive layer 33 completely covers the orifice layer 31 . On the one hand, the second adhesive layer 33 is located inside the pressure chamber 21 , so it is in direct contact with the ink. Then, the second adhesive layer 33 isolates the ink from the orifice layer 31 , reducing the corrosiveness of the ink to the orifice layer 31 .

[0113] On the other hand, the second adhesive layer 33 is used to bond the orifice layer 31 and the cavity wall 22. When the second adhesive layer 33 is applied, the second adhesive layer 33 is directly applied to the orifice layer 31, and then the cavity wall 22 is directly applied to the second adhesive layer 33, thereby achieving bonding between the cavity wall 22 and the second adhesive layer 33. It is easier to process the orifice layer 31 by completely covering the second adhesive layer 33, especially compared with the processing technology of only partially applying the second adhesive layer 33 at the connection between the orifice layer 31 and the cavity wall 22, completely applying and covering the second adhesive layer 33 can be faster and simpler, and the accuracy is easier to control, which helps to improve the processing efficiency of the second adhesive layer 33.

[0114] The thickness of the spray hole layer 31 is 0.005-0.1 mm; preferably, the thickness of the spray hole layer 31 is 0.01-0.05 mm.

[0115] Specifically, the thickness of the injection hole layer 31 is: 0.005mm, 0.006mm, 0.007mm, 0.008mm, 0.009mm, 0.01mm, 0.015mm, 0.02mm, 0.025mm, 0.03mm, 0.035mm, 0.04mm, 0.045mm, 0.05mm, 0.055mm, 0.06mm, 0.065mm, 0.07mm, 0.075mm, 0.08mm, 0.086mm, 0.09mm, 0.095mm, and 0.1mm.

[0116] In summary, the present application provides a print head, in which an isolation groove 11 is provided on the piezoelectric ceramic 1, and the isolation groove 11 isolates the vibration area of ​​the piezoelectric ceramic 1. When the piezoelectric ceramic 1 is energized, the vibration area of ​​the piezoelectric ceramic 1 vibrates, and then the mechanical crosstalk generated by the vibration area is isolated by the isolation groove 11, thereby reducing the mechanical crosstalk of adjacent vibration areas, thereby improving the printing accuracy of the print head. On the other hand, by providing the isolation groove 11 on the outside of the piezoelectric ceramic 1, or filling the isolation groove 11 with a filler, the piezoelectric ceramic 1 can be sealed and connected to the cavity wall 22. The connection strength and sealing between the piezoelectric ceramic 1 and the cavity wall 22 are improved.

[0117] In addition, in the present application, the cavity wall 22 and the nozzle hole layer 31 are both made of metal material, which has extremely high wear resistance and hardness, thereby greatly improving the overall strength of the print head, thereby making the print head have a longer service life.

[0118] Example 1

[0119] The present application provides a print head, in which an isolation groove 11 is opened on a piezoelectric ceramic 1, thereby reducing the mechanical crosstalk of the piezoelectric ceramics 1 on adjacent pressure chambers 21.

[0120] The piezoelectric ceramic 1 is 70 mm long, 10 mm wide and 0.2 mm thick. The first adhesive layer 13 is made of an organic material with a thickness of 0.05 mm.

[0121] The thickness of the cavity wall 22 is 0.2 mm, and the cavity wall 22 is made of stainless steel, and a protective layer of iron nitride is provided on the cavity wall 22. The pressure cavity 21 is a cavity with a length of 8 mm, a width of 0.5 mm, and a thickness of 0.2 mm.

[0122] The spray hole layer 31 is a stainless steel layer with a thickness of 0.05 mm, and the spray hole 32 is a circular hole with a diameter of 0.05 mm.

[0123] The second adhesive layer 33 is an adhesive layer made of epoxy resin and is used to fix the cavity wall 22 and the spray hole layer 31 .

[0124] The isolation groove 11 is formed on the upper end surface of the piezoelectric ceramic 1;

[0125] The depth of the isolation groove 11 formed in the piezoelectric ceramic 1 is 20% of the total thickness of the piezoelectric ceramic 1 .

[0126] The printing liquid used in the print head is furan resin.

[0127] Example 2

[0128] Except for the difference in the opening of the isolation groove 11 in this embodiment, the rest of the structure and material are the same as those in the embodiment 1.

[0129] The isolation groove 11 is formed on the upper end surface of the piezoelectric ceramic 1;

[0130] The depth of the isolation groove 11 opened on the piezoelectric ceramic 1 is 50% of the total thickness of the piezoelectric ceramic 1;

[0131] Example 3

[0132] Except for the difference in the opening of the isolation groove 11 in this embodiment, the rest of the structure and material are the same as those in the embodiment 1.

[0133] The isolation groove 11 is formed on the lower end surface of the piezoelectric ceramic 1;

[0134] The depth of the isolation groove 11 opened on the piezoelectric ceramic 1 is 20% of the total thickness of the piezoelectric ceramic 1;

[0135] Example 4

[0136] Except for the difference in the opening of the isolation groove 11 in this embodiment, the rest of the structure and material are the same as those in the embodiment 1.

[0137] The isolation groove 11 is formed on the lower end surface of the piezoelectric ceramic 1;

[0138] The depth of the isolation groove 11 opened on the piezoelectric ceramic 1 is 50% of the total thickness of the piezoelectric ceramic 1;

[0139] Except that the isolation groove 11 is not provided in this comparative example, the rest of the structure and material are the same as those in the embodiment 1.

[0140] The print heads in Examples 1 to 4 and the comparative example were subjected to printing tests, and the operating states of the print heads were recorded.

[0141] Table 1 Working status of the print head in Examples 1 to 4

[0142] Example Isolation slot Print Status Example 1 Upper end surface 20% Able to increase effective injection frequency to 16K Example 2 Upper end surface 50% Able to increase effective injection frequency to 21K Example 3 Lower end surface 20% Able to increase effective injection frequency to 12K Example 4 Lower end face 50% Able to increase effective injection frequency to 14K

[0143] Table 2 Variation of ink droplet size with jetting frequency (unit: picoliter)

[0144] 2K 4k 6k 8K 10K 12K 14K 16K 18K 20K 22K Example 1 65.4 66.8 68.2 70.6 72.1 76.8 77.8 78.6 60 Example 2 68.2 70.3 72.2 73 75.3 76.1 78.2 78.5 79.6 82.5 80 Example 3 66.2 68.6 73.8 74.2 74.6 75 48 Example 4 64.3 64.6 66.8 68.3 73.9 76.5 77 52 Comparative Example 62.3 63.8 67.5 68.8 69.6 69 51

[0145] Note: The jet frequency is the ignition frequency; it can also be called the printing frequency.

[0146] It can be seen from Examples 1 to 4 and the comparative example. After the jetting frequency of the comparative example reaches 10k, the size of the ink droplets will become smaller as the jetting frequency increases. Examples 1 to 4 are all increased compared to the comparative example, and the results are shown in Table 1 above. Among them, when an isolation groove is opened on the upper end surface of the piezoelectric ceramic, and the depth of the isolation groove is 50% of the total thickness of the piezoelectric ceramic 1, the jetting frequency of the print head can be increased to 21K. Furthermore, a higher ignition frequency can eject more ink, increase the printing speed of the print head, and increase the printing efficiency of the print head.

[0147] Example 5

[0148] The structure of this embodiment is completely the same as that of Embodiment 1. In this embodiment, the material of the second adhesive layer 33 is an adhesive film. The adhesive film is used to connect the cavity wall 22 and the orifice layer 31. The thickness of the adhesive film is 0.02 mm.

[0149] In this embodiment, the adhesive film is a F806P EVA adhesive film.

[0150] Example 6

[0151] The structure of this embodiment is completely the same as that of Embodiment 1. In this embodiment, the material of the second adhesive layer 33 is an adhesive film. The adhesive film is used to connect the cavity wall 22 and the orifice layer 31. The thickness of the adhesive film is 0.045 mm.

[0152] In this embodiment, the adhesive film is a F806P EVA adhesive film.

[0153] Example 7

[0154] The structure of this embodiment is completely the same as that of Embodiment 1. In this embodiment, the material of the second adhesive layer 33 is epoxy resin. The cavity wall 22 and the orifice layer 31 are connected by epoxy. The thickness of the epoxy is 0.01 mm.

[0155] Example 8

[0156] The structure of this embodiment is completely the same as that of Embodiment 1. In this embodiment, the material of the second adhesive layer 33 is epoxy resin. The cavity wall 22 and the orifice layer 31 are connected by epoxy. The thickness of the epoxy is 0.02 mm.

[0157] Example 9

[0158] The structure of this embodiment is completely the same as that of Embodiment 1. In this embodiment, the material of the second adhesive layer 33 is acrylic acid. Acrylic acid is used to connect the cavity wall 22 and the orifice layer 31. The thickness of the acrylic acid is 0.02 mm.

[0159] Example 10

[0160] The structure of this embodiment is completely the same as that of Embodiment 1. In this embodiment, the material of the second adhesive layer 33 is acrylic acid. Acrylic acid is used to connect the cavity wall 22 and the orifice layer 31. The thickness of the acrylic acid is 0.03 mm.

[0161] Embodiment 11

[0162] The structure in this embodiment is completely the same as that in Embodiment 1. In this embodiment, the material of the second adhesive layer 33 is organic silica gel (conventional adhesive). The thickness of the adhesive is 0.02 mm.

[0163] The bonding effect of different second adhesive layers 33 on the cavity wall 22 (surface material is aluminum oxide) and the orifice layer 31 (surface material is stainless steel) in Examples 5 to 11, the connection strength refers to the tensile strength.

[0164]

[0165]

[0166] It can be seen from Examples 5 to 11 that when the second adhesive layer is epoxy resin or acrylic, compared with conventional silicone adhesion, the connection strength between the cavity wall and the orifice layer is significantly increased, reducing the possibility of separation between the orifice layer and the cavity wall; and improving the stability of the print head.

[0167] Among them, acrylic acid has a stable chemical property that is difficult to react with the ink in the print head; therefore, using acrylic acid to connect the cavity wall and the nozzle layer can significantly increase the service life of the print head.

[0168] When the second adhesive layer is a film, the connection strength between the cavity wall and the nozzle hole layer is significantly improved. It also has a very long service life. Compared with conventional silicone connections, it has significant progress and extremely high performance improvement.

[0169] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed. However, as long as it is within the scope of the claims of the present application, it shall be protected by the patent law.

Claims

1. A print head, wherein: The ink storage device comprises a liquid storage component for storing ink, a driving component and a nozzle component, wherein the driving component and the nozzle component are respectively located on both sides of the liquid storage component, and the driving component can make the ink in the liquid storage component spray out from the nozzle component; The driving member includes a piezoelectric ceramic; an isolating portion is provided on the piezoelectric ceramic to isolate the piezoelectric ceramic to be compatible with the liquid storage member; Preferably, the isolation portion is an isolation groove opened on the piezoelectric ceramic.

2. The print head according to claim 1, wherein: The liquid storage component comprises a plurality of mutually independent pressure chambers, ink is stored in the pressure chambers, the piezoelectric ceramic covers one end of the pressure chambers; the isolation groove is opened between two adjacent pressure chambers; Preferably, the liquid storage member includes a cavity wall forming a pressure cavity, the cavity wall is provided with a plurality of cavities, the cavity wall is connected to the piezoelectric ceramic, and the isolation groove is correspondingly opened at the connection between the cavity wall and the piezoelectric ceramic; Further preferably, the piezoelectric ceramic includes a vibration area corresponding to the pressure cavity, the vibration area is located at one end of the pressure cavity and seals the pressure cavity, and the isolation groove is opened between two adjacent vibration areas.

3. The print head according to claim 2, wherein: The depth of the isolation groove is 10% to 80% of the thickness of the piezoelectric ceramic; Preferably, the depth of the isolation groove is 20% to 60% of the thickness of the piezoelectric ceramic; Further preferably, the depth of the isolation groove is 40% to 50% of the thickness of the piezoelectric ceramic.

4. The print head according to claim 2, wherein: The isolation groove is arranged on a side of the piezoelectric ceramic close to the liquid storage member; Alternatively, the isolation groove is opened on a side of the piezoelectric ceramic facing away from the liquid storage member.

5. The print head according to any one of claims 1 to 4, wherein: The isolation groove is filled with an isolation agent; Preferably, a first adhesive layer is provided between the driving member and the liquid storage member; More preferably, the first adhesive layer and the filler are made of the same material.

6. The print head according to any one of claims 1 to 5, wherein: The liquid storage member comprises a cavity wall, and the material of the cavity wall is metal; Preferably, the cavity wall is made of stainless steel or aluminum alloy.

7. The print head according to claim 6, wherein: A protective layer is provided on the cavity wall; Preferably, the protective layer is an aluminum alloy layer; Further preferably, the protective layer is an aluminum oxide layer; Further preferably, when the cavity wall is made of aluminum alloy, the protective layer is an aluminum alloy layer.

8. The print head according to claim 6, wherein: A protective layer is provided on the cavity wall; Preferably, the protective layer is a nitride layer; Further preferably, the protective layer is an iron nitride layer; Further preferably, the protective layer is a nitrided stainless steel layer; Further preferably, when the cavity wall is made of stainless steel, the protective layer is a nitride layer.

9. The print head according to any one of claims 1 to 8, wherein: The spray hole component comprises a spray hole layer, on which a plurality of spray holes corresponding to the liquid storage component are opened; Preferably, the spray hole layer is made of metal; Further preferably, the spray hole layer is made of stainless steel or nickel alloy.

10. The print head according to claim 9, wherein: A second adhesive layer is provided between the spray hole component and the liquid storage component; the second adhesive layer is used for connecting the spray hole component and the liquid storage component; Preferably, the second adhesive layer is arranged between the orifice layer and the cavity wall; Further preferably, the second adhesive layer covers the orifice layer; Further preferably, the second adhesive layer is an adhesive film, an epoxy layer, or an acrylic layer.

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