Methods for determining the obstruction structure and design parameters in a nozzle.

Abstract

This disclosure provides a method for determining the design parameters of a nozzle slit structure and its design parameters. The nozzle slit structure includes an inlet connecting component, a narrowing component, and an outlet connecting component arranged sequentially. The method includes: obtaining the total length and total width of the nozzle slit structure, and the narrowing length and narrowing width of the narrowing component; determining a first angle range between the inlet connecting component and the narrowing component, and a second angle range between the outlet connecting component and the narrowing component, based on the total length, total width, narrowing length, and narrowing width; calculating the ink supply efficiency of the nozzle slit structure based on the first and second angle ranges; and determining a first design angle between the inlet connecting component and the narrowing component, and a second design angle between the outlet connecting component and the narrowing component, based on the ink supply efficiency. This disclosure results in lower flow resistance when ink flows into the vibrating cavity through the nozzle, but higher flow resistance when flowing out of the vibrating cavity, thereby effectively shortening the ink filling time and improving inkjet efficiency.

Description

Technical Field

[0001] This disclosure relates to the field of microfluidics, and in particular to a method for determining the design parameters of a nozzle's obstruction structure. Background Technology

[0002] In the field of piezoelectric inkjet printing, when a vibrating cavity vibrates, a positive or negative pressure is generated inside the cavity depending on the direction of vibration. Generally, when the cavity is under negative pressure, the fluid (ink) flows into the cavity; conversely, when the cavity is under positive pressure, the fluid flows out. By repeatedly applying positive and negative pressure inside the vibrating cavity, the piezoelectric printhead can fill and eject ink.

[0003] Existing piezoelectric printheads have a slit structure to regulate the fluid ratio of the ink inlet and outlet channels in the vibrating cavity. However, because the connection angle on both sides of the slit structure cannot be adjusted, the flow resistance of the slit is the same when supplying and dispensing ink, resulting in low inkjet efficiency. Summary of the Invention

[0004] The technical problem to be solved by this disclosure is to overcome the defect in the prior art that the inlet and outlet connection angle of the choke structure cannot be adjusted, resulting in low inkjet efficiency, and to provide a method for determining the choke structure and its design parameters in the printhead.

[0005] This disclosure solves the above-mentioned technical problems through the following technical solution:

[0006] A first aspect of this disclosure provides a method for determining the design parameters of a pass structure, the pass structure comprising an inlet connecting component, a narrowing component, and an outlet connecting component arranged sequentially, the method comprising:

[0007] Obtain the total length and total width of the pass structure, as well as the narrow length and narrow width of the narrow opening component;

[0008] Based on the total length, the total width, the narrow opening length, and the narrow opening width, a first angle range between the inlet connecting component and the narrow opening component, and a second angle range between the outlet connecting component and the narrow opening component are determined.

[0009] The ink supply efficiency of the narrow passage structure is calculated based on the first angle range and the second angle range.

[0010] Based on the ink supply efficiency, a first design angle between the inlet connection component and the narrow opening component, and a second design angle between the outlet connection component and the narrow opening component are determined.

[0011] Optionally, the step of determining the first angle range of the inlet connecting component and the second angle range of the outlet connecting component based on the total length, the total width, the narrow opening length, and the narrow opening width includes:

[0012] The first length range of the inlet connecting component and the second length range of the outlet connecting component are determined based on the total length and the narrow opening length.

[0013] The first angle range and the second angle range are determined based on the total width, the narrow opening width, the first length range, and the second length range.

[0014] Optionally, the step of calculating the ink supply efficiency of the choke structure based on the first angle range and the second angle range includes:

[0015] First target angles are selected sequentially from the first angle range. Based on the total length, the total width, the narrow opening length, and the narrow opening width, several second target angles corresponding to each first target angle are determined from the second angle range.

[0016] Wherein, the first target angle is greater than the second target angle;

[0017] Based on the first target angle and each corresponding second target angle, the ink supply resistance and backflow resistance of the choke structure are calculated respectively.

[0018] Based on the ink supply resistance and the backflow resistance, the ink supply efficiency of the choke structure under different first target angles and second target angles is determined.

[0019] Optionally, the step of determining the first design angle between the inlet connection component and the narrow opening component, and the second design angle between the outlet connection component and the narrow opening component based on the ink supply efficiency, includes:

[0020] Based on process requirements, a target ink supply efficiency is determined from several ink supply efficiencies, and the first target angle and the second target angle corresponding to the target ink supply efficiency are respectively used as the first design angle and the second design angle.

[0021] A second aspect of this disclosure provides a narrowing structure in a nozzle, the narrowing structure comprising an inlet connection component, a narrowing component, and an outlet connection component connected in sequence.

[0022] The inlet connection component is connected to the ink inlet, and the outlet connection component is connected to the vibration cavity;

[0023] The inlet connecting component and the narrow opening component are at a first design angle;

[0024] The outlet connecting component and the narrow opening component are at a second design angle;

[0025] The first design angle and the second design angle are obtained based on the determination method described in the first aspect of this disclosure.

[0026] Optionally, the first design angle is greater than the second design angle;

[0027] And / or,

[0028] The first design angle and the second design angle are formed based on a dry etching process;

[0029] And / or,

[0030] The range of values ​​for the first design angle is: ;

[0031] And / or,

[0032] The range of values ​​for the second design angle is: .

[0033] A third aspect of this disclosure provides a flow channel structure in a nozzle, said flow channel structure including the obstruction structure described in the second aspect of this disclosure.

[0034] A fourth aspect of this disclosure provides a microelectromechanical system (MEMS) device, the MEMS device including the flow channel structure described in the third aspect of this disclosure.

[0035] A fifth aspect of this disclosure provides an inkjet unit that includes the microelectromechanical system (MEMS) device described in the fourth aspect of this disclosure.

[0036] A sixth aspect of this disclosure provides a piezoelectric inkjet head, the piezoelectric inkjet head including the inkjet unit described in the fifth aspect of this disclosure.

[0037] Based on common knowledge in the field, the above optional conditions can be combined arbitrarily to obtain the optional examples of this disclosure.

[0038] The positive and progressive effects of this disclosure are as follows: By combining the total length and width of the choke structure and the narrow length and width of the narrow-mouth component, the inkjet efficiency corresponding to different inlet and outlet design angles is determined. This allows for the determination of the first and second design angles that ensure the flow resistance of ink flowing into the vibrating cavity through the choke structure is less than the flow resistance when flowing out of the vibrating cavity. This results in lower flow resistance when ink flows into the vibrating cavity through the choke, but higher flow resistance when flowing out of the vibrating cavity. Consequently, the ink filling time is effectively shortened, inkjet efficiency is improved, and the proportion of ink flowing from the vibrating cavity to the nozzle is increased, thereby increasing the droplet flight speed. At the same time, under a lower driving voltage, the same droplet volume can be ejected, reducing energy consumption. Attached Figure Description

[0039] Figure 1 This is a first schematic diagram of the pass structure disclosed herein;

[0040] Figure 2 This is a flowchart illustrating the method for determining the design parameters of the pass structure disclosed herein.

[0041] Figure 3 This is a graph showing the relationship between the loss coefficient and the flow channel angle of this disclosure.

[0042] Figure 4 An example diagram illustrating the method for determining the design parameters of the pass structure disclosed herein;

[0043] Figure 5 This is a second schematic diagram of the pass structure disclosed herein. Detailed Implementation

[0044] The present disclosure is further illustrated below by way of embodiments, but the present disclosure is not limited to the scope of the embodiments described herein.

[0045] The prefixes such as "first" and "second" used in this disclosure are merely for distinguishing different descriptive objects and do not limit the position, order, priority, quantity, or content of the described objects. The use of ordinal numbers and other prefixes used to distinguish descriptive objects in this disclosure does not constitute a limitation on the described objects. The description of the described objects is given in the context of the embodiments, and the use of such prefixes should not constitute unnecessary restrictions. Furthermore, in the description of this embodiment, unless otherwise stated, "multiple" means two or more.

[0046] Example 1

[0047] In one specific embodiment, a method for determining the design parameters of a pass structure is provided, such as... Figure 1 As shown, the pass structure includes an entrance connecting component, a narrowing component, and an exit connecting component arranged sequentially, such as... Figure 2 As shown, the determination method includes:

[0048] S1. Obtain the total length and total width of the pass structure, as well as the narrow length and narrow width of the narrow passage component;

[0049] S2. Based on the total length, total width, narrow opening length, and narrow opening width, determine the first angle range between the inlet connecting component and the narrow opening component, and the second angle range between the outlet connecting component and the narrow opening component;

[0050] S3. Calculate the ink supply efficiency of the narrow passage structure based on the first angle range and the second angle range.

[0051] S4. Determine the first design angle between the inlet connection component and the narrow opening component based on ink supply efficiency. And the second design angle of the outlet connection component and the narrow opening component. .

[0052] Specifically, such as Figure 1 As shown, the inlet connecting component and the outlet connecting component have ramps on at least one side, which connect the two sides of the narrow opening component to form a narrow opening structure.

[0053] When designing printheads for Micro Electro-Mechanical Systems (MEMS), it is usually necessary to first confirm the printhead's product specifications, such as printing technology, resolution, droplet size, number and arrangement of nozzles, drive frequency, and compatible ink types. Then, based on the confirmed key parameters, the actuator structure and fluid system are designed.

[0054] Within the design parameter constraints of the actuator structure, the total length and width of the obstruction structure in the flow channel structure, as well as the narrow length and width of the narrow opening component within the obstruction structure, can be designed. The total length, total width, narrow opening length, and narrow opening width are obtained through step S1 as the basis for subsequent parameter design. Note that the total length of the obstruction structure is greater than the narrow opening length.

[0055] Once the total length and width of the pass structure, as well as the narrow length and width of the narrow opening component in the pass structure, are determined, the ramp angles connecting the inlet connecting component, the outlet connecting component, and the narrow opening component in the pass structure will also be different when the narrow opening component is in different positions in the pass structure. Therefore, the first angle range between the inlet connecting component and the narrow opening component, and the second angle range between the outlet connecting component and the narrow opening component can be determined through step S2.

[0056] As a fluid (e.g., ink) flows through a slowly expanding or contracting channel, turbulence is generated due to friction between the fluid and the channel. This effect can be converted into equivalent flow resistance. The equivalent flow resistance differs depending on the pressure drop generated during channel expansion and contraction, and can be calculated using formula (1):

[0057] (1)

[0058] in, Indicates pressure loss, Indicates fluid density, Indicates fluid velocity.

[0059] When calculating the pressure loss during flow channel expansion, the loss factor can be used. The loss coefficient is expressed as follows: The relationship with the flow channel expansion angle is as follows: Figure 3 As shown.

[0060] Therefore, by utilizing this characteristic of fluids, the ink supply resistance corresponding to different first angles of connection between the inlet connecting component and the narrow opening component, and the check flow resistance corresponding to different second angles of connection between the outlet connecting component and the narrow opening component can be calculated through step S3. Then, the ink supply efficiency corresponding to different design angles can be calculated based on the ink supply resistance and the check flow resistance. In this case, the ink supply efficiency = (check flow resistance - ink supply resistance) / check flow resistance * 100%.

[0061] Then, by determining the target ink supply efficiency based on actual process requirements in step S4, the optimal first design angle can be determined. Second design angle This design aims to reduce flow resistance when the material flows into the vibrating cavity through the narrow passage, but increases flow resistance when it flows out of the vibrating cavity.

[0062] This specific embodiment determines the inkjet efficiency corresponding to different inlet and outlet design angles by combining the total length and width of the obstruction structure and the narrow length and width of the narrow-mouth component. This results in a first design angle and a second design angle that ensure the flow resistance of ink flowing into the vibrating cavity through the obstruction structure is less than the flow resistance when flowing out of the vibrating cavity. This makes the flow resistance of ink flowing into the vibrating cavity lower, but the flow resistance of ink flowing out of the vibrating cavity higher, thereby effectively shortening the ink filling time, improving inkjet efficiency, and increasing the proportion of ink flowing from the vibrating cavity to the nozzle, thereby increasing the droplet flight speed. At the same time, it can achieve the ejection of the same droplet volume under a lower driving voltage, reducing energy consumption.

[0063] In one specific embodiment, step S2 includes:

[0064] S21. Determine the first length range of the inlet connecting component and the second length range of the outlet connecting component based on the total length and the narrow opening length;

[0065] S22. Determine the first angle range and the second angle range based on the total width, the narrow opening width, the first length range, and the second length range.

[0066] Specifically, after determining the total length and width of the gutter structure, as well as the narrow opening length and width of the narrow opening component within the gutter structure, a first length range for the inlet connecting component and a second length range for the outlet connecting component can be allocated. Since a larger flow channel expansion angle results in greater pressure loss, to ensure lower flow resistance when ink flows into the vibrating cavity through the gutter and higher flow resistance when it flows out of the vibrating cavity, the connection angle between the inlet connecting component and the narrow opening component must be larger than the connection angle between the outlet connecting component and the narrow opening component. Therefore, given a fixed width of the gutter structure and the narrow opening component, the first length range allocated to the inlet connecting component must be less than or equal to the second length range allocated to the outlet connecting component.

[0067] Then, based on the total width, the narrow opening width, and the allocated first length range and second length range, the first angle range and the second angle range are determined.

[0068] In one specific implementation, step S3 includes:

[0069] S31. Select first target angles sequentially from the first angle range, and determine several second target angles corresponding to each first target angle from the second angle range based on the total length, total width, narrow opening length and narrow opening width;

[0070] Among them, the angle of the first target is greater than the angle of the second target;

[0071] S32. Based on the first target angle and each corresponding second target angle, calculate the ink supply resistance and backflow resistance of the choke structure respectively;

[0072] S33. Determine the ink supply efficiency of the choke structure at different first target angles and second target angles based on the ink supply resistance and backflow resistance.

[0073] Specifically, after the total length and width of the choke structure, as well as the narrow length and width of the narrow opening component in the choke structure, are determined, once the first angle connecting the inlet connecting component and the narrow opening component is determined, the range of values ​​for the second angle connecting the outlet connecting component and the narrow opening component is also determined. Then, within the first angle range, a first target angle and several second target angles corresponding to the first target angle can be selected sequentially. In order to make the flow resistance lower when the ink flows into the vibration cavity through the choke and higher when it flows out of the vibration cavity, it is necessary to ensure that the first target angle is greater than the second target angle so that the flow resistance changes faster with the angle at the inlet connecting component, that is, the rate of change of the flow resistance at the inlet connecting component is greater than that at the outlet connecting component.

[0074] After obtaining the correspondence between the first target angle and the second target angle, the ink supply resistance and anti-backflow resistance of the choke structure can be calculated, thereby obtaining the ink supply efficiency for each pair of the first target angle and the second target angle.

[0075] For example, when the first target angle = 90° and the second target angle = 20°, the ink supply efficiency = 9.26%; when the first target angle = the second target angle = 35°, the ink supply efficiency = 0.00%; when the first target angle = 45° and the second target angle = 30°, the ink supply efficiency = 29.27%.

[0076] In one specific embodiment, step S4 includes: determining a target ink supply efficiency from several ink supply efficiencies based on process requirements, and using the first target angle and the second target angle corresponding to the target ink supply efficiency as the first design angle, respectively. Second design angle .

[0077] Specifically, since different products have different nozzle densities and actuator structures, the connection angles on both sides of the choke structure can be determined according to the specific product specifications to match the target ink supply efficiency. Then, the choke structure is designed based on the first target angle and the second target angle corresponding to the ink supply efficiency, so that the flow resistance is lower when the ink flows into the vibration cavity through the choke, but higher when it flows out of the vibration cavity.

[0078] For example, if the target ink supply efficiency is set at 29.27%, then the first design angle can be determined. The second design angle is 45°. It is 30°.

[0079] In a specific example, such as Figure 4As shown, after confirming the printhead product specifications, actuator structure design, and fluid system design, the total length and width of the choke structure, as well as the narrow length and width of the narrow-mouth component, are first confirmed, ensuring that the total length is greater than the narrow length. Next, the length range of the inlet and outlet connecting components is allocated, ensuring that the length of the inlet connecting component is less than or equal to the length of the outlet connecting component. Then, the angle range of the inlet and outlet connecting components is determined based on the allocated length range, and the ink supply efficiency is calculated to ensure that the ink supply flow resistance is less than the backflow resistance, thereby determining the matching first design angle and second design angle.

[0080] This embodiment combines the total length and width of the obstruction structure with the narrow length and width of the narrow-mouth component to determine the inkjet efficiency corresponding to different inlet and outlet design angles. This results in a first and a second design angle where the flow resistance of ink flowing into the vibrating cavity through the obstruction structure is less than the flow resistance when flowing out of the vibrating cavity. This makes the flow resistance of ink flowing into the vibrating cavity lower, but the flow resistance when flowing out of the vibrating cavity higher, thereby effectively shortening the ink filling time, improving inkjet efficiency, and increasing the proportion of ink flowing from the vibrating cavity to the nozzle, thus increasing the droplet flight speed. At the same time, it can achieve the ejection of the same droplet volume under a lower driving voltage, reducing energy consumption.

[0081] Example 2

[0082] In one specific embodiment, a narrowing structure is provided in the nozzle, such as... Figure 1 As shown, the pass structure includes an inlet connecting component, a narrowing component, and an outlet connecting component connected in sequence.

[0083] The inlet connection component connects to the ink inlet, and the outlet connection component connects to the vibration cavity.

[0084] The inlet connecting component and the narrow opening component are at the first design angle. ;

[0085] The outlet connecting component and the narrow-mouth component are at a second design angle. ;

[0086] Among them, the first design angle Second design angle Based on the determination method in Embodiment 1 above, and the first design angle Greater than the second design angle .

[0087] Specifically, the narrowing structure consists of three parts: an inlet connecting component, a narrowing component, and an outlet connecting component. The inlet connecting component connects to the ink inlet, and the outlet connecting component connects to the vibration cavity. At least one side of the inlet connecting component is a ramp, through which it connects to the narrowing component at a first design angle. The outlet connection component has at least one side with a ramp, through which it connects to the narrow-mouth component at a second design angle. By designing different angles on both sides of the narrow-mouth component, a lower flow resistance is achieved when the vibration cavity is under negative pressure and fluid flows in, and a higher flow resistance is achieved when the vibration cavity is under positive pressure and fluid flows out. This provides different flow resistances under positive and negative pressure conditions in the vibration cavity, thereby effectively improving inkjet efficiency.

[0088] Since the etching direction of the wet etching process is affected by the wafer crystallization direction and cannot be freely processed, the choke structure with the first design angle and the second design angle in this specific embodiment can be prepared using deep silicon etching technology (a dry etching process).

[0089] In one feasible way, such as Figure 5 As shown, both sides of the inlet connecting component and the outlet connecting component are ramps, which are respectively at a first design angle to the narrow opening component. Second design angle Among them, the first design angle Second design angle This was obtained based on the determination method described in Example 1 above.

[0090] In one specific implementation, the first design angle The range of values ​​is Second design perspective The range of values ​​is .

[0091] This embodiment combines the total length and width of the obstruction structure with the narrow length and width of the narrow-mouth component to determine the inkjet efficiency corresponding to different inlet and outlet design angles. This results in a first and a second design angle where the flow resistance of ink flowing into the vibrating cavity through the obstruction structure is less than the flow resistance when flowing out of the vibrating cavity. This makes the flow resistance of ink flowing into the vibrating cavity lower, but the flow resistance when flowing out of the vibrating cavity higher, thereby effectively shortening the ink filling time, improving inkjet efficiency, and increasing the proportion of ink flowing from the vibrating cavity to the nozzle, thus increasing the droplet flight speed. At the same time, it can achieve the ejection of the same droplet volume under a lower driving voltage, reducing energy consumption.

[0092] Example 3

[0093] In one specific embodiment, a flow channel structure in a nozzle is provided, which includes the obstruction structure in Embodiment 2 above.

[0094] Specifically, the flow channel structure in the printhead is a complete fluid channel network that connects the ink chamber, piezoelectric actuator and nozzle inside the printhead, providing a stable and controllable ink environment for the inkjet process. It can be fabricated on a silicon substrate. The choke structure in the flow channel structure is used to smoothly transition the front-stage transition channel, avoiding sharp angles or abrupt cross sections, thereby reducing local flow resistance and eddies, and ensuring the continuity of ink flow.

[0095] This embodiment combines the total length and width of the obstruction structure with the narrow length and width of the narrow-mouth component to determine the inkjet efficiency corresponding to different inlet and outlet design angles. This results in a first and a second design angle where the flow resistance of ink flowing into the vibrating cavity through the obstruction structure is less than the flow resistance when flowing out of the vibrating cavity. This makes the flow resistance of ink flowing into the vibrating cavity lower, but the flow resistance when flowing out of the vibrating cavity higher, thereby effectively shortening the ink filling time, improving inkjet efficiency, and increasing the proportion of ink flowing from the vibrating cavity to the nozzle, thus increasing the droplet flight speed. At the same time, it can achieve the ejection of the same droplet volume under a lower driving voltage, reducing energy consumption.

[0096] Example 4

[0097] In one specific embodiment, a microelectromechanical system (MEMS) device is provided, which includes the flow channel structure in embodiment 3 above.

[0098] Specifically, MEMS devices achieve miniaturization and integration of flow channels through microfabrication processes, and endow the flow channels with core functions such as sensing, driving, and control. The flow channel structure serves as the physical channel for fluid transmission in the MEMS system, ensuring that the MEMS structure can realize complex functions such as sensing, driving, and control.

[0099] This embodiment combines the total length and width of the obstruction structure with the narrow length and width of the narrow-mouth component to determine the inkjet efficiency corresponding to different inlet and outlet design angles. This results in a first and a second design angle where the flow resistance of ink flowing into the vibrating cavity through the obstruction structure is less than the flow resistance when flowing out of the vibrating cavity. This makes the flow resistance of ink flowing into the vibrating cavity lower, but the flow resistance when flowing out of the vibrating cavity higher, thereby effectively shortening the ink filling time, improving inkjet efficiency, and increasing the proportion of ink flowing from the vibrating cavity to the nozzle, thus increasing the droplet flight speed. At the same time, it can achieve the ejection of the same droplet volume under a lower driving voltage, reducing energy consumption.

[0100] Example 5

[0101] In one specific embodiment, an inkjet unit is provided, which includes the microelectromechanical system device described in embodiment 4 above.

[0102] Specifically, an inkjet unit is a device module composed of MEMS devices, flow channel structures, nozzle structures, support structures, etc. By embedding MEMS devices into the inkjet unit, the inkjet unit can achieve intelligent control requirements such as precise sensing, rapid control, and miniaturized integration through micron-level functional structures.

[0103] This embodiment combines the total length and width of the obstruction structure with the narrow length and width of the narrow-mouth component to determine the inkjet efficiency corresponding to different inlet and outlet design angles. This results in a first and a second design angle where the flow resistance of ink flowing into the vibrating cavity through the obstruction structure is less than the flow resistance when flowing out of the vibrating cavity. This makes the flow resistance of ink flowing into the vibrating cavity lower, but the flow resistance when flowing out of the vibrating cavity higher, thereby effectively shortening the ink filling time, improving inkjet efficiency, and increasing the proportion of ink flowing from the vibrating cavity to the nozzle, thus increasing the droplet flight speed. At the same time, it can achieve the ejection of the same droplet volume under a lower driving voltage, reducing energy consumption.

[0104] Example 6

[0105] In one specific embodiment, a piezoelectric inkjet head is provided, which includes the inkjet unit in embodiment 5 above.

[0106] Specifically, piezoelectric inkjet heads (e.g., MEMS printheads) integrate an inkjet unit, which can eject ink droplets at high speed from a single nozzle. The voltage can be adjusted to control the size of the ink droplets, ensuring high-quality printing from the piezoelectric inkjet head.

[0107] This embodiment combines the total length and width of the obstruction structure with the narrow length and width of the narrow-mouth component to determine the inkjet efficiency corresponding to different inlet and outlet design angles. This results in a first and a second design angle where the flow resistance of ink flowing into the vibrating cavity through the obstruction structure is less than the flow resistance when flowing out of the vibrating cavity. This makes the flow resistance of ink flowing into the vibrating cavity lower, but the flow resistance when flowing out of the vibrating cavity higher, thereby effectively shortening the ink filling time, improving inkjet efficiency, and increasing the proportion of ink flowing from the vibrating cavity to the nozzle, thus increasing the droplet flight speed. At the same time, it can achieve the ejection of the same droplet volume under a lower driving voltage, reducing energy consumption.

[0108] While specific embodiments of this disclosure have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of this disclosure is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of this disclosure, but all such changes and modifications fall within the scope of protection of this disclosure.

Claims

1. A method for determining the design parameters of a pass structure, characterized in that, The pass structure includes an inlet connecting component, a narrowing component, and an outlet connecting component arranged sequentially, and the method for determining the pass includes: Obtain the total length and total width of the pass structure, as well as the narrow length and narrow width of the narrow opening component; Based on the total length, the total width, the narrow opening length, and the narrow opening width, a first angle range between the inlet connecting component and the narrow opening component, and a second angle range between the outlet connecting component and the narrow opening component are determined. The ink supply efficiency of the narrow passage structure is calculated based on the first angle range and the second angle range. Based on the ink supply efficiency, determine the first design angle between the inlet connection component and the narrow opening component, and the second design angle between the outlet connection component and the narrow opening component; The step of determining the first angle range of the inlet connecting component and the second angle range of the outlet connecting component based on the total length, the total width, the narrow opening length, and the narrow opening width includes: The first length range of the inlet connecting component and the second length range of the outlet connecting component are determined based on the total length and the narrow opening length. The first angle range and the second angle range are determined based on the total width, the narrow opening width, the first length range, and the second length range; The step of calculating the ink supply efficiency of the narrow passage structure based on the first angle range and the second angle range includes: First target angles are selected sequentially from the first angle range. Based on the total length, the total width, the narrow opening length, and the narrow opening width, several second target angles corresponding to each first target angle are determined from the second angle range. Wherein, the first target angle is greater than the second target angle; Based on the first target angle and each corresponding second target angle, the ink supply resistance and backflow resistance of the choke structure are calculated respectively. Based on the ink supply resistance and the backflow resistance, the ink supply efficiency of the choke structure under different first target angles and second target angles is determined.

2. The determination method according to claim 1, characterized in that, The steps of determining the first design angle between the inlet connection component and the narrow opening component, and the second design angle between the outlet connection component and the narrow opening component based on the ink supply efficiency, include: Based on process requirements, a target ink supply efficiency is determined from several ink supply efficiencies, and the first target angle and the second target angle corresponding to the target ink supply efficiency are respectively used as the first design angle and the second design angle.

3. A narrow passage structure in a nozzle, characterized in that, The pass structure includes an inlet connecting component, a narrowing component, and an outlet connecting component connected in sequence. The inlet connection component is connected to the ink inlet, and the outlet connection component is connected to the vibration cavity; The inlet connecting component and the narrow opening component are at a first design angle; The outlet connecting component and the narrow opening component are at a second design angle; The first design angle and the second design angle are obtained based on the determination method described in claim 1 or 2.

4. The pass structure according to claim 3, characterized in that, The first design angle is greater than the second design angle; And / or, The first design angle and the second design angle are formed based on a dry etching process; And / or, The range of values ​​for the first design angle is: ~ ; And / or, The range of values ​​for the second design angle is: ~ .

5. A flow channel structure in a nozzle, characterized in that, The flow channel structure includes the pass structure as described in claim 3 or 4.

6. A microelectromechanical system (MEMS) device, characterized in that, The microelectromechanical system device includes the flow channel structure as described in claim 5.

7. An inkjet unit, characterized in that, The inkjet unit includes the microelectromechanical system device as described in claim 6.

8. A piezoelectric inkjet head, characterized in that, The piezoelectric inkjet head includes the inkjet unit as described in claim 7.

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