Spray head for spraying target object

Abstract

The invention relates to a spray head for spraying a target object. The spray head comprises one or more spray head units, and each spray head unit comprises a liquid supply unit used for supplying liquid to be sprayed to a flow channel; the flow channel is communicated with the flow channel connecting port of each capillary tube in the capillary tube group; each row of capillary tube group comprises a plurality of capillary tubes, each capillary tube comprises a main body part, a flow channel connecting port and a liquid outlet, and the flow channel connecting port and the liquid outlet are respectively arranged at two end parts of the main body part; the shape and the size of the liquid outlet are configured to enable the liquid to be sprayed to be output from the liquid outlet in a continuous output mode. According to the invention, the manufacturing cost is relatively low, flying liquid discharge can be avoided, and the liquid spraying efficiency can be improved.

Description

Technical Field

[0001] The present invention relates generally to inkjet printing technology, and in particular, to a spray head for spraying a target object. Background Art

[0002] In existing nozzles, for example, for coloring or spraying a target object (e.g., fabric), the liquid to be sprayed (e.g., ink) is atomized by ultrasonic atomization technology so as to be printed on the target object. Since the atomization of the liquid to be sprayed requires additional energy consumption, and the atomized droplets (e.g., ink droplets) that are not attached to the target object require a matching absorption device to reduce the impact on the environment. Although the above-mentioned existing nozzles based on ultrasonic atomization technology have technical advantages such as saving the liquid to be sprayed and the printing pattern is precisely controllable, they need to be equipped with a transducer for realizing ultrasonic atomization and an absorption device for absorbing excess atomized ink droplets, which makes the manufacturing cost high. In addition, the efficiency of atomized liquid coloring or spraying is poor.

[0003] In summary, the disadvantages of conventional nozzles are: high manufacturing cost, problems of flying liquid (eg, flying ink) discharge, and poor liquid spraying (eg, ink spraying) efficiency. Summary of the invention

[0004] The present invention provides a spray head for spraying a target object, which can have a lower manufacturing cost, avoid flying liquid discharge and improve liquid spraying efficiency.

[0005] According to a first aspect of the present invention, there is provided a nozzle for spraying a target object, the nozzle comprising one or more nozzle units, each nozzle unit comprising: a liquid supply unit for supplying liquid to be sprayed to a flow channel; a flow channel, the flow channel being connected to a flow channel connection port of each capillary in a capillary group; and one or more rows of capillary groups, each row of the capillary group comprising a plurality of capillaries, each capillary comprising a main body portion, a flow channel connection port and a liquid outlet, the flow channel connection port and the liquid outlet being respectively arranged at two ends of the main body portion, the shape and size of the liquid outlet being configured so that the liquid to be sprayed is output from the liquid outlet in a continuous output manner.

[0006] In some embodiments, the continuous output is in the form of liquid column output.

[0007] In some embodiments, the liquid supply unit includes a plurality of liquid inlets, and the flow channel is configured to adjust flow rates of the plurality of liquid inlets so that flow rates of the liquid to be sprayed at locations where the plurality of capillaries are located are different from each other.

[0008] In some embodiments, the flow channel is configured as a longitudinal groove, the bottom surface of the longitudinal groove is an arc surface, an opening connected to the flow channel connection port of the capillary is provided on the arc surface, and the height of the longitudinal groove is less than or equal to a predetermined height threshold.

[0009] In some embodiments, the two ends of the main body of the capillary are respectively the flow channel connection end and the liquid outlet end, the outer diameter of the first end of the liquid outlet end is larger than the outer diameter of the second end of the liquid outlet end, the first end of the liquid outlet end is connected to the main body, and the second end of the liquid outlet end is provided with the liquid outlet.

[0010] In some embodiments, an angle between a side wall of the liquid outlet end of the capillary and a radial cross section of the capillary is greater than or equal to 10 degrees.

[0011] In some embodiments, the flow channel connection port is located at a first end of the flow channel connection end, and at least a portion of the liquid outlet end is configured as a tapered tube.

[0012] In some embodiments, the ratio of the inner diameter and the outer diameter of the second end of the liquid outlet is configured to be less than a predetermined range from a transition ratio threshold value, and the transition ratio threshold value corresponds to a transition liquid outlet flow rate, which is the corresponding liquid outlet flow rate when the liquid to be sprayed is output from the liquid outlet in a dripping manner to a continuous spraying manner.

[0013] In some embodiments, the liquid supply unit also includes: a liquid distributor, including a distributor inlet and multiple distributor outlets; multiple flow limiting valves, the input end of each flow limiting valve is connected to the corresponding distributor outlet among the multiple distributor outlets; and multiple groups of proportional valves, the output end of each flow limiting valve is connected to the corresponding group of proportional valves among the multiple groups of proportional valves.

[0014] In some embodiments, the multiple proportional valves included in each group of proportional valves in the plurality of groups of proportional valves are respectively connected to the multiple liquid inlets in the corresponding spray head unit.

[0015] In some embodiments, each nozzle unit also includes: a base plate having multiple mounting holes for mounting a capillary group and limiting the spacing between the capillaries; a flow channel plate having one or more of the flow channels configured on the first surface of the flow channel plate; and a side wall, wherein the side wall, the base plate, and the second surface of the flow channel plate form a accommodating space for the capillary group.

[0016] In some embodiments, each nozzle unit includes: a plurality of sealing rings, each of the plurality of sealing rings is arranged on the outside of the flow channel connecting end of the corresponding capillary tube to seal the capillary tube.

[0017] In some embodiments, the sealing ring is disposed in a sealing ring snap groove on the second side of the flow channel plate, and the flow channel is configured on the first surface of the flow channel plate.

[0018] In some embodiments, the bottom plate of the nozzle unit has a splicable structure for splicing the bottom plates of adjacent nozzle units.

[0019] In some embodiments, the shape, size, and distance between the liquid outlet and the target object are configured so that the liquid to be sprayed in a continuous liquid column section rather than a turbulent section where the liquid column changes into liquid droplets is provided to the target object.

[0020] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the invention, nor is it intended to limit the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A longitudinal cross-sectional view of a spray head for spraying a target object according to some embodiments of the present invention is shown.

[0022] Figure 2 A side view of a receiving space of a capillary tube set according to some embodiments of the present invention is shown.

[0023] Figure 3 A top view of a flow channel plate according to some embodiments of the present invention is shown.

[0024] Figure 4 A transverse cross-sectional view of a spray head unit according to some embodiments of the present invention is shown.

[0025] Figure 5 A bottom view of a sparger unit according to some embodiments of the present invention is shown.

[0026] Figure 6 A partial enlarged view of a capillary according to some embodiments of the present invention is shown.

[0027] Figure 7 A cross-sectional view of a portion of a capillary according to some embodiments of the present invention is shown.

[0028] Figure 8 A schematic structural diagram of a capillary according to some embodiments of the present invention is shown.

[0029] Fig. 9 A schematic diagram of an equivalent circuit of fluid characteristics of a flow channel and a capillary group according to some embodiments of the present invention is shown.

[0030] Fig.10 A schematic diagram showing continuous output and drip output according to some embodiments of the present invention.

[0031] Fig.11A schematic diagram of a liquid supply unit according to some embodiments of the present invention is shown.

[0032] Fig.12 A schematic diagram of a showerhead unit group according to some embodiments of the present invention is shown.

[0033] In the various drawings, the same or corresponding reference numerals represent the same or corresponding parts. DETAILED DESCRIPTION

[0034] The preferred embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0035] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "based at least in part on". The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. may refer to different or the same objects.

[0036] As described above, the disadvantages of conventional nozzles are: high manufacturing cost and the problem of flying liquid discharge.

[0037] In order to at least partially solve one or more of the above problems and other potential problems, an exemplary embodiment of the present invention proposes a spray head for spraying a target object, wherein the spray head includes one or more spray head units, each of which includes: a liquid supply unit for providing the liquid to be sprayed to the flow channel; a flow channel, the flow channel being connected to the flow channel connection port of each capillary in the capillary group; and one or more rows of capillary groups, each row of capillary groups including a plurality of capillaries, each capillary including a main body, a flow channel connection port and a liquid outlet, the flow channel connection port and the liquid outlet are respectively arranged at two ends of the main body, and the shape and size of the liquid outlet are configured so that the liquid to be sprayed is output from the liquid outlet in a continuous output manner. Since the capillary group that outputs the liquid to be sprayed from the liquid outlet in a continuous output manner is used to replace the liquid spraying method based on the transducer technology of ultrasonic atomization, the present invention significantly reduces the manufacturing cost, and the liquid spraying efficiency is higher, and no flying liquid is generated. Therefore, the present invention can have a lower manufacturing cost and can avoid flying liquid discharge.

[0038] The following combination Figure 1 A spray head 100 for spraying a target object is exemplarily illustrated. Figure 1 A longitudinal cross-sectional view of a spray head 100 for spraying a target object according to some embodiments of the present invention is shown.

[0039] The showerhead 100 includes, for example, one or more showerhead units. Figure 1 The figure shows a nozzle including a nozzle unit. Figure 1 As shown, each nozzle unit includes a liquid supply unit, a flow channel 110, one or more rows of capillary groups 120 ( Figure 1 Two rows of capillary groups are shown in the example).

[0040] Regarding the liquid supply unit, it is used to supply the liquid to be sprayed to the flow channel. The liquid supply unit supplies the liquid to be sprayed to the flow channel in the form of a constant current source, for example. In some embodiments, the liquid supply unit includes a plurality of liquid inlets 150. Figure 1 As shown, each nozzle unit includes, for example, three liquid inlets 150 (a first liquid inlet 150-1 located on the left side of the flow channel, a second liquid inlet 150-2 located in the middle of the flow channel, and a third liquid inlet 150-3 located on the right side of the flow channel). In some embodiments, the liquid supply unit of each nozzle unit includes, for example, two liquid inlets 150, such as Fig.11 It should be understood that the liquid supply unit may also include other numbers of liquid inlets.

[0041] The liquid to be sprayed may be, for example, functional liquids such as ink, dye, medicine, treatment liquid, etc. In some embodiments, the liquid to be sprayed is ink for coloring the target fabric.

[0042] The flow channel 110 is used to supply the liquid to be ejected from the liquid supply unit to the capillary group 120. The flow channel 110 is communicated with the flow channel connection port of each capillary in the capillary group 120. Figure 1 Only the portion of the flow channel 110 exposed by the liquid inlet 150 is shown.

[0043] Regarding the target object, it is, for example, a target fabric, a target substrate, and the like.

[0044] Regarding the capillary group 120, it is used to output the liquid to be sprayed from the flow channel to the target object. Each nozzle unit includes one or more rows of capillary groups 120. Each row of capillary groups 120 includes multiple capillaries. Each capillary includes: a main body, a flow channel connection port and a liquid outlet. The flow channel connection port and the liquid outlet are respectively arranged at two ends of the main body, and the shape and size of the liquid outlet are configured so that the liquid to be sprayed is output from the liquid outlet in a continuous output manner. Regarding the continuous output method, it is, for example, a liquid column output method, rather than a discontinuous method like droplets. It should be understood that since the liquid to be sprayed is output from the liquid outlet in a continuous output manner, the present invention can significantly improve the liquid spraying efficiency.

[0045] The continuous output method may be, for example, a continuous liquid column output method. Fig.10 Schematic diagrams of continuous output and drip output according to some embodiments of the present invention are shown. Fig.10 As shown in the left part of , the liquid to be sprayed is discharged from the liquid outlet of the capillary in a continuous output manner. Fig.10 As shown in the left part of FIG. 1 , the liquid to be sprayed continuously output from the liquid outlet of the capillary includes, for example, a continuous liquid column section 111, a turbulent section 113 where the liquid column changes into liquid droplets, and liquid droplets 117. Fig.10 As shown in the right part of the figure, the liquid to be sprayed is discharged from the liquid outlet of the capillary in a non-continuous manner of dripping. The liquid to be sprayed discharged from the liquid outlet of the capillary in a dripping manner includes, for example, a droplet generating area 119 and droplets 117. It should be understood that the shape and size of the liquid outlet of the present invention are configured so that the liquid to be sprayed is discharged in a non-continuous manner. Fig.10 In some embodiments, the shape, size, and distance between the liquid outlet and the target object of the present invention are configured so that the liquid to be sprayed in the continuous liquid column section 111 rather than the turbulent section 113 where the liquid column changes into liquid droplets is provided to the target object, thereby significantly improving the spraying effect of the target object.

[0046] It should be understood that when the liquid to be sprayed flows in the flow channel and the capillary tube, there will be flow resistance in the flow channel and the capillary tube. The magnitude of the flow resistance is usually determined by the viscosity of the fluid, the length and radius of the flow channel. Fig. 9 FIG. 2 shows a schematic diagram of an equivalent circuit of fluid characteristics of a flow channel and a capillary group according to some embodiments of the present invention. Fig. 9 As shown, it includes N flow channel segments and N capillaries (N is, for example, a positive integer. In some embodiments, N is an even number). In the flow channel, the flow channel segment between each two openings has a certain flow resistance, such as Fig. 9 R L1 Indicates the flow resistance of the first flow channel section (i.e., the flow channel before the first capillary); R LN Indicates the flow resistance of the Nth flow channel segment. It should be understood that the flow resistance of the entire flow channel is similar to multiple flow channel segments "in series". Each flow channel segment also has "inductive reactance" (inductive reactance indicates the property of the flow channel that hinders the flow change of the fluid flow rate, such as Fig. 9 Medium L1 Indicates the inductive reactance of the first flow channel section; L LN Indicates the inductive reactance of the Nth flow channel segment). Each capillary connected to the opening of the flow channel also has a flow resistance (such as Fig. 9 Medium R Z1 Indicates the flow resistance of the first capillary; R ZN Indicates the flow resistance of the Nth capillary), inductive reactance (such as Fig. 9 Medium Z1Indicates the inductive reactance of the first capillary; L ZN Indicating the inductive reactance of the Nth capillary). In addition, each set of flow channel segments and capillaries also has a "capacitive reactance" represented by the gas and liquid therein (the capacitive reactance indicates the storage capacity of the fluid represented by the gas and liquid, such as Fig. 9 Middle C LZ1 Indicates the capacitive reactance of the first flow channel section and the first capillary; C LZN Indicates the capacitive reactance of the Nth flow channel section and the Nth capillary). In addition, Fig. 9 I L Indicates a constant current source connected to one end (eg, the left end) of the flow channel; I M Indicates a constant current source connected to the middle of the flow channel (for example, it is connected near the N / 2 capillary); I R Indicates a constant current source connected to the other end (e.g., right end) of the flow channel. Fig. 9 As shown, one end of the three constant current sources is connected and "grounded" (such as Fig. 9 The inverted triangle in the figure indicates grounding). It should be understood that in the fluid characteristic equivalent circuit, "voltage" is equivalent to fluid pressure; "current" is equivalent to fluid flow. "Grounding" is equivalent to being connected to atmospheric pressure. It should be understood that the outlet of each capillary is connected to atmospheric pressure, which is equivalent to "grounding" at one end of the capillary.

[0047] The following is an exemplary description of the calculation methods of inductive reactance, capacitive reactance and flow resistance in combination with formulas (1) to (3).

[0048]

[0049] In the above formula (1), L LN represents the inductive reactance of the Nth flow channel section. ρ represents the density of the liquid to be sprayed. LN Represents the length of the Nth flow channel section. R represents the cross-sectional area of ​​the Nth flow channel segment (taking a circular cross-sectional area as an example). It should be understood that the calculation method of the inductive reactance of the capillary is similar.

[0050]

[0051] In the above formula (2), C LZN Represents the capacitive reactance of the Nth flow channel section and the Nth capillary. V LZN represents the volume of the Nth flow channel segment and the Nth capillary tube. B represents the bulk modulus of the Nth flow channel segment and the Nth capillary tube.

[0052]

[0053] In the above formula (3), R LN represents the flow resistance of the Nth flow channel section. μ represents the viscosity of the liquid to be sprayed.LN Represents the length of the Nth flow channel section. LN Represents the radius of the cross section of the Nth flow channel segment (taking a circular cross section as an example). As can be seen from the above formula (3), the radius of the cross section of the flow channel segment has a relatively large impact on the flow resistance. A small change in the radius will bring about a significant change in the flow resistance. It should be understood that the flow resistance of the capillary is calculated in a similar manner. In addition, formulas (1) to (3) take a flow channel and / or capillary with a circular cross section as an example. The cross sections of the flow channel and capillary can also be other shapes.

[0054] In some embodiments, the flow resistance of the flow channel is configured to adjust the flow rates of the multiple liquid inlets so that the flow rates of the liquid to be sprayed at the locations of the multiple capillaries are different from each other. Fig. 9 I L Indicates a constant current source connected to one end (eg, the left end) of the flow channel, which is, for example, connected to the first liquid inlet 150 - 1 located on the left side of the flow channel. Fig. 9 I M Indicates a constant current source connected to the middle of the flow channel, which is, for example, connected to the second liquid inlet 150-2 located in the middle of the flow channel. Fig. 9 I RIndicates a constant current source connected to the other end (e.g., the right end) of the flow channel, which is, for example, connected to the third liquid inlet 150-3 located on the right side of the flow channel. In some embodiments, if the flow resistance of the flow channel is relatively large, in a steady state, the linear change of the flow rate at the capillary can be achieved by controlling the inlet flow rate of the first liquid inlet 150-1 located on the left side of the flow channel, the second liquid inlet 150-2 located in the middle of the flow channel, and the third liquid inlet 150-3 located on the right side of the flow channel. For example, the flow rate at each capillary changes gradually from left to right. For example, the inlet flow rate of the first liquid inlet 150-1 located on the left side of the flow channel is 100% of the predetermined value; the inlet flow rate of the second liquid inlet 150-2 located in the middle of the flow channel is -100% of the predetermined value; and the inlet flow rate of the third liquid inlet 150-3 located on the right side of the flow channel is 100% of the predetermined value. At this time, the inlet flow rate at both ends of the flow channel is a high flow rate, and the inlet flow rate in the middle is a low flow rate, so that the flow rates at different capillaries are different. For another example, the liquid inlet flow rate of the first liquid inlet 150-1 located on the left side of the flow channel is 100% of the predetermined value; the liquid inlet flow rate of the second liquid inlet 150-2 located in the middle of the flow channel is -50% of the predetermined value; the liquid inlet flow rate of the third liquid inlet 150-3 located on the right side of the flow channel is 50% of the predetermined value. It should be understood that, for example, in the process of spraying and dyeing the fabric, before the fabric enters the printing area, the fabric will present a state of uneven density over the entire width due to the pretreatment process. If the amount of dye (i.e., liquid to be sprayed) applied is the same during printing, the final coloring of the fabric will be uneven. The present invention controls the liquid inlet flow rates of multiple liquid inlets located at different positions of the flow channel to achieve different liquid outlet flow rates at different capillaries (for example, linear changes). This can output different flow rates of liquid to be sprayed at different capillaries in response to the state of uneven density of the fabric over the entire width, thereby achieving uniform coloring or spraying of the entire fabric.

[0055] Regarding the main part of the capillary (such as Figure 4 The two ends at both ends of the main body are respectively the flow channel connection ends (such as Figure 4 124) and a liquid outlet end 122.

[0056] The following combination Figures 6 to 8 The structure of the liquid outlet end 122 of the capillary will be described in detail. Figure 6 A partial enlarged view of a capillary according to some embodiments of the present invention is shown. Figure 7 A cross-sectional view of a portion of a capillary according to some embodiments of the present invention is shown. Figure 8 FIG. 4 shows a schematic diagram of the structure of a capillary according to some embodiments of the present invention. Figure 6As shown, one end of the main body 126 of the capillary is the liquid outlet 122. The first end 127 of the liquid outlet 122 is connected to the main body 126, and the second end 128 of the liquid outlet 122 is the liquid outlet.

[0057] In some embodiments, the outer diameter of the first end 127 of the liquid outlet 122 (eg, Figure 7 and Figure 8 ) is larger than the outer diameter of the second end 128 of the liquid outlet end 122 (e.g., Figures 6 to 8 . In this way, it is helpful to control the liquid flow rate of the liquid outlet. It should be understood that the outer diameter DN of the first end 127 of the liquid outlet 122 is the outer diameter of the capillary. In some embodiments, the outer diameter of the capillary is greater than or equal to 0.1 mm.

[0058] Regarding the inner diameter of the liquid outlet end 122, in some embodiments, the inner diameter (dn) of the first end 127 of the liquid outlet end 122 is equal to the inner diameter (d) of the second end 128 of the liquid outlet end 122, such as Figure 7 In some embodiments, the inner diameter (dn) of the first end 127 of the liquid outlet 122 is greater than the inner diameter (d) of the second end 128 of the liquid outlet 122. Figure 8 In other embodiments, the inner diameter of the first end 127 of the liquid outlet end 122 is equal to the inner diameter of the second end 128 of the liquid outlet end 122, and the outer diameter of the first end 128 of the liquid outlet end 122 is equal to the outer diameter of the second end 128 of the liquid outlet end 122. In some embodiments, the inner diameter (d) of the second end 128 of the liquid outlet end 122 is equal to the outer diameter (D) of the second end 128 of the liquid outlet end 122. In some embodiments, the inner diameter (d) of the second end 128 of the liquid outlet end 122 is greater than or equal to 0.02 mm.

[0059] In some embodiments, the outer wall profile of the liquid outlet end 122 is configured as an arc, a step, or a segment. In some embodiments, at least a portion of the liquid outlet end 122 is configured as a conical tube. Figure 7 As shown, the entire liquid outlet 122 is configured as a tapered tube, for example. It should be understood that the outer diameter of the tapered tube gradually decreases, and the inner diameter of the tapered tube may remain unchanged or gradually decrease. Figure 7 As shown, in the direction extending from the first end 127 to the second end 128 (d), the outer diameter of the liquid outlet end 122 gradually decreases from the outer diameter (DN) at the first end 127 until it is reduced to the outer diameter (D) of the second end 128; at the same time, the inner diameter of the liquid outlet end 122 remains unchanged, that is, equal to the inner diameter of the second end 128. It should be understood that by configuring the liquid outlet end as a tapered tube with a constant inner diameter, it is convenient to control the liquid outlet flow rate and facilitate processing.

[0060] Figure 8The cross-sectional view in the upper right corner of FIG. 1 is an enlarged view of the area surrounded by the circle indicated by the mark 121. Figure 8 As shown, a portion of the liquid outlet end 122 is configured as a tapered tube, for example, the liquid outlet end 122 is configured as a combination of a tapered tube and a cylindrical tube. The axial height n of the tapered tube is less than or equal to the axial height of the liquid outlet end 122. The difference between the outer diameter (DN) at the first end 127 and the inner diameter (dn) of the first end 127 may be equal to or different from the difference between the outer diameter (D) of the second end 128 and the inner diameter (d) of the second end 128. In the direction from the first end 127 to the second end 128 (d), the outer diameter of the liquid outlet end 122 gradually decreases from the outer diameter of the end of the cylindrical tube until it decreases to the outer diameter (D) of the second end 128; at the same time, the inner diameter of the liquid outlet end 122 gradually decreases from the inner diameter (dn) of the first end 127 until it decreases to the inner diameter (d) of the second end 128. It should be understood that by configuring at least a portion of the liquid outlet end as a tapered tube with reduced inner and outer diameters, it is beneficial to more effectively control the liquid outlet flow rate. Regarding the side wall of the liquid outlet end of the capillary, in some embodiments, as Figure 7 As shown, the angle θ between the side wall 810 of the liquid outlet end of the capillary and the radial cross section 812 of the capillary is greater than or equal to 10 degrees. In some embodiments, the angle θ is any value greater than or equal to 10 degrees and less than 90 degrees. In some embodiments, the angle θ is any value greater than or equal to 80 degrees and less than 90 degrees. By setting the angle θ within the above-mentioned angle range, it is possible to avoid the liquid output from the liquid outlet from wetting the side of the liquid outlet so as to promote the formation of a continuous liquid column. It should be understood that if the liquid output from the liquid outlet wets the side of the liquid outlet, an asymmetric wetting condition is easily formed, which in turn has a negative impact on the output of the continuous liquid column from the liquid outlet.

[0061] like Figure 6 As shown, arrow 123 indicates the inner diameter of the second end 128 of the liquid end 122, which is represented by the letter "d". Arrow 125 indicates the outer diameter of the second end 128 of the liquid end 122, which is represented by the letter "D".

[0062] The following is a description of the inner diameter d and outer diameter D of the liquid outlet and the critical Weber number by combining formulas (4) to (6): relationship.

[0063]

[0064] B0=[ρgD 2 / (2σ)] 1 / 2 (5)

[0065]

[0066] In the above formula (4), represents the critical Weber number. B0 and represent the Bond number based on the inner and outer diameters of the outlet, respectively. K represents a constant. B0 and The ratio is related to the ratio of the inner diameter to the outer diameter. In the above formulas (5) and (6), ρ represents the density of the liquid to be sprayed. σ represents the surface tension of the liquid to be sprayed. g represents the acceleration of gravity. v0 represents the flow rate of the liquid to be sprayed. D represents the inner diameter (diameter) of the capillary at the outlet. It should be understood that the Weber number is a characteristic number used in fluid mechanics, which characterizes the ratio of the deformation inertia force and the stable cohesive force when the liquid (for example, the liquid to be sprayed) flows through a fluid medium (for example, a capillary). The cohesive force is related to the surface tension or interfacial tension, which prevents the increase of the surface area, thereby causing deformation. Therefore, the droplets of the liquid to be sprayed will gather together due to the surface tension or interfacial tension. Critical Weber number The Weber number of the liquid to be sprayed with a density ρ and a surface tension σ, when the liquid passes through the liquid outlet with an inner diameter D at a flow rate v0, from the liquid droplet mode to the continuous spray mode (or "continuous output mode", for example, a liquid column). It should be understood that the critical Weber number The transition flow rate is associated with the transition from a dripping mode to a continuous spraying mode in which the liquid to be sprayed is output from the liquid outlet.

[0067] Regarding the transition flow rate, for example, the liquid to be sprayed is output from the liquid outlet in a manner such that Fig.10 The dripping method (or "drip output method") shown on the right side is Fig.10 The left side shows the corresponding flow rate when the continuous injection mode (also called "continuous output mode" or "liquid column mode") is changed.

[0068] Studies have shown that when the inner diameter of the capillary (for example, the inner diameter of the liquid outlet is equal to the inner diameter of the capillary) is small enough, the interface of the liquid to be sprayed can be stabilized to Rayleigh-Taylor instability (RT instability). In this state, the inertia of the liquid to be sprayed, the capillary action of the capillary and the gravity of the liquid to be sprayed are dominant compared to the viscosity of the liquid to be sprayed. When the inner diameter d of the liquid outlet is unchanged, the closer the outer diameter D is to the inner diameter d (that is, the smaller the outer diameter D is), the smaller the transition flow rate of the liquid to be sprayed output from the liquid outlet from the dripping mode to the continuous spraying mode. In some embodiments, the ratio of the inner diameter to the outer diameter of the second end of the liquid outlet is configured to be less than a predetermined range from the difference of the transition ratio threshold, and the transition ratio threshold corresponds to the transition liquid outlet flow rate, which is the corresponding liquid outlet flow rate when the liquid to be sprayed is output from the liquid outlet from the dripping mode to the continuous spraying mode.

[0069] like Figure 1 and Figure 2 As shown, in some embodiments, each spray head unit further includes: a bottom plate 130 , a side wall 132 , a flow channel plate 134 , and a plurality of sealing rings 140 .

[0070] The bottom plate 130 has a plurality of mounting holes for mounting the capillary tube set 120 and defining the intervals between the capillaries.

[0071] Regarding the flow channel plate 134, its first surface (eg, Figure 1 In some embodiments, the second surface of the flow channel plate 134 (for example, the upper surface of the flow channel plate 134) is configured with one or more flow channels 110. Figure 1 A sealing ring snap groove for snapping the sealing ring 140 is provided on the lower surface of the flow channel plate 134.

[0072] The side wall 132, the bottom plate 130, and the second surface of the flow channel plate 134 form a receiving space for the capillary group 120. In some embodiments, the side wall 132 includes at least a first side wall 132-1 and a second side wall 132-2 (eg, Figure 2 shown).

[0073] Regarding the sealing ring 140, it is used to seal the capillary. In some embodiments, the number of sealing rings is equal to the number of capillaries. Figure 1 As shown, each sealing ring is arranged on the outer side of the flow channel connecting end of the corresponding capillary tube to seal the capillary tube. Figure 1 The dotted frame in the upper left corner is a partial enlarged view of the portion within the virtual line indicated by the mark 102, which indicates that each sealing ring 140 is sleeved on the outer side of the flow channel connecting end of the corresponding capillary tube, and the sealing ring is set in the sealing ring buckle groove on the second side of the flow channel plate 134.

[0074] In some embodiments, each showerhead unit further includes, for example: a top plate 138 , a sealing plate 136 , and a mounting plate 142 .

[0075] Regarding the top plate 138 , it is configured to be located on the upper surface of the spray head unit. In some embodiments, the top plate 138 is used to install one or more liquid inlets 150 .

[0076] Regarding the sealing plate 136, it is disposed between the top plate 138 and the flow channel plate 134 to seal the communication space between the flow channel and the liquid inlet 150. In some embodiments, the sealing plate 136 and the top plate 138 are both provided with a through hole (e.g., Figure 2 The top plate through hole 139 and the sealing plate through hole 137 are shown in order to guide the liquid to be sprayed from the liquid inlet 150 to the flow channel 110.

[0077] Regarding the mounting plate 142 , it is, for example, disposed between the flow channel plate 134 and the side wall 132 to achieve relative fixation between the flow channel plate 134 and the side wall 132 .

[0078] The following combination Figure 2 A schematic diagram illustrating the accommodation space of a capillary group. Figure 2 A side view of a receiving space of a capillary tube set according to some embodiments of the present invention is shown.

[0079] Regarding the accommodation space 135 of the capillary group, in some embodiments, as Figure 2 As shown, it is, for example, defined by at least the side wall 132 (the side wall 132 specifically includes, for example, the first side wall 132-1 and the second side wall 132-2), the upper surface of the bottom plate 130, and the second surface (i.e., the lower surface) of the flow channel plate 134. It should be understood that each nozzle unit includes, for example, a capillary group accommodation space 135. Each capillary group accommodation space 135, for example, accommodates one or more rows of capillary groups. Figure 2 As shown, the accommodating space 135 of the capillary tube group accommodates two rows of capillary tube groups.

[0080] The following combination Figure 3 A schematic diagram illustrating the flow channel plate 134 is shown. Figure 3 A top view of a flow channel plate according to some embodiments of the present invention is shown.

[0081] like Figure 3 As shown, the flow channel plate 134 has a first surface (ie, the upper surface of the flow channel plate 134 ) and a second surface (ie, the lower surface of the flow channel plate 134 ).

[0082] For example, a plurality of flow channels 110 are disposed on the first surface of the flow channel plate 134 . Figure 3 Schematically showing that the first surface of the flow channel plate 134 includes two flow channels. It should be understood that the number of flow channels 110 configured by the flow channel plate 134 of each nozzle unit is equal to the number of rows of the capillary group, and each flow channel 110 is used to provide the corresponding row of capillaries 120 with liquid to be sprayed. Each flow channel 110, for example, includes a plurality of openings, and the flow channel is connected to the flow channel connection port of the corresponding capillary in the capillary group through the opening. In some embodiments, the flow channel plate 134 is also provided with a plurality of mounting holes 114 for achieving relative fixation between the flow channel plate 134 and the sealing plate 136, the mounting plate 142 and / or the side wall 132.

[0083] Regarding the flow channel 110, in some embodiments, the flow resistance of the flow channel is configured to adjust the flow rates of the multiple liquid inlets so that the flow rates of the liquid to be sprayed at the locations where the multiple capillaries are located are different from each other. Figure 3As shown, the mark 112-M indicates the Mth opening, and the Mth opening 112-M corresponds to the position of the Mth capillary, for example. The mark 112-N indicates the Nth opening. The Nth opening corresponds to the position of the Nth capillary, for example. It should be understood that the flow resistance of the flow channel 110 is configured, for example, to adjust the flow rate of the multiple liquid inlets so that the liquid outflow rate of the multiple capillaries at the position of the Mth capillary and the position of the Nth capillary are different from each other.

[0084] In some embodiments, the flow channel 110 is configured as a longitudinal groove, the bottom surface of the longitudinal groove is a curved surface, and an opening hole connected to the flow channel connection port of the capillary is provided on the curved surface. It should be understood that by setting the bottom surface of the flow channel 110 as a curved surface, the flow channel of the present invention can reduce the residual liquid to be sprayed in the flow channel.

[0085] As for the longitudinal grooves, for example, they are along Figure 3 In some embodiments, the longitudinal groove is a long and narrow shallow groove extending in the X direction. In some embodiments, the cross section of the longitudinal groove is semicircular. In some embodiments, the height of the longitudinal groove is less than or equal to a predetermined height threshold. Regarding the predetermined height threshold, it is, for example but not limited to, 1 mm. For example, in some embodiments, the height of the longitudinal groove is configured to be 0.5 mm. By making the height of the longitudinal groove very low, that is, making the longitudinal groove be configured as a long and narrow shallow groove, it is convenient to control the flow resistance of the flow channel. In some embodiments, the width of the longitudinal groove is, for example, 1 mm.

[0086] It should be understood that, under low flow resistance, a slight change in the flow resistance in the pipeline will significantly affect the stability of the flow rate of the liquid to be sprayed. By making the flow resistance of the flow channel larger (for example, making the flow resistance of the flow channel exceed a predetermined flow resistance threshold), the stability of the flow rate of the liquid to be sprayed output by the nozzle can be improved.

[0087] In some embodiments, the cross-sectional area of ​​the flow channel is, for example, configured to be less than a predetermined cross-sectional area threshold. In some embodiments, the cross-sectional area of ​​the flow channel is, for example but not limited to, 0.5 square millimeters. In some embodiments, the cross-sectional area of ​​the flow channel is determined based on the sensitivity requirements of the flow control of the liquid to be sprayed by the nozzle. It should be understood that the flow resistance in the microfluidic is mainly caused by the pressure drop and energy loss caused by the friction between the liquid and the channel wall. Experimental data show that when the viscous liquid to be sprayed is in a laminar state, the closer the liquid to be sprayed is to the flow channel wall, the greater its flow resistance and the corresponding flow rate; under the same pressure, the smaller the inner diameter of the flow channel, the greater the flow resistance and the lower the flow rate. Therefore, the present invention increases the flow resistance in the flow channel and reduces the flow rate by configuring the flow channel as a narrow and shallow groove and making its cross-sectional size small enough, thereby improving the sensitivity of the flow control of the liquid to be sprayed by the nozzle.

[0088] Figure 4 A transverse cross-sectional view of a spray head unit according to some embodiments of the present invention is shown.

[0089] like Figure 3 and Figure 4 As shown, the bottom plate 130 is provided with a mounting hole. The mounting plate 142 is provided with a mounting hole. The side wall 132 is also provided with a mounting hole. The first mounting device 144 passes through the mounting holes on the bottom plate 130, the side wall 132 and the mounting plate 142 in sequence, thereby achieving the fixing between the bottom plate 130, the side wall 132 and the mounting plate 142.

[0090] like Figure 4 As shown, the top plate 138, the sealing plate 136, the flow channel plate 134 and the mounting plate 142 are relatively fixed by coupling the second mounting device 146 with the mounting holes on the top plate 138, the sealing plate 136, the flow channel plate 134 and the mounting plate 142 respectively.

[0091] In some embodiments, the first mounting device 144 and the second mounting device 146 are configured as bolts, for example. In some embodiments, the first mounting device 144 and the second mounting device 146 can be coupled and decoupled.

[0092] It should be understood that, through the above-mentioned installation method, the present invention facilitates local maintenance and installation. For example, the first installation device 144 can be decoupled from the bottom plate 130, the side wall 132 and the mounting holes on the mounting plate 142 to conveniently realize the disassembly of the bottom plate 130 and the side wall 132, thereby conveniently carrying out the installation and maintenance of the capillary without affecting the relative fixation between the top plate 138, the sealing plate 136, the flow channel plate 134 and the mounting plate 142. Similarly, the second installation device 146 can be decoupled from the mounting holes on the top plate 138, the sealing plate 136, the flow channel plate 134 and the mounting holes on the mounting plate 142 to conveniently realize the disassembly of the top plate 138, the sealing plate 136, the flow channel plate 134, thereby conveniently carrying out the installation and maintenance of the flow channel or the liquid inlet without affecting the relative fixation between the bottom plate 130, the side wall 132 and the capillary group.

[0093] Figure 4 The dotted box in the upper right corner is an enlarged view of the local structure in the dotted box indicated by the mark 148. The mark 112 indicates the opening of the flow channel. The opening 112 is, for example, located on the bottom surface of the flow channel of the first surface 115 of the flow channel plate 134. The opening 112 is connected to the flow channel connection end of the capillary tube, and is used to provide the liquid to be sprayed in the flow channel to the capillary tube through the opening 112. The liquid to be sprayed provided to the capillary tube flows through the flow channel connection end of the capillary tube, the main body 126, and finally outputs from the liquid outlet at the second end (i.e., the end) of the liquid outlet end 122.

[0094] Figure 4It is also shown that the second surface 118 of the flow channel plate 134 is provided with a sealing ring snap groove 116. The sealing ring snap groove 116 is used to snap the sealing ring 140 so that the sealing ring 140 is fixed outside the flow channel connection end of the capillary tube to seal the flow channel connection end of the capillary tube. Figure 5 A bottom view of a sparger unit according to some embodiments of the present invention is shown.

[0095] In some embodiments, the ratio of the inner diameter and the outer diameter of the second end of the liquid outlet is configured to be less than a predetermined range from a transition ratio threshold value, and the transition ratio threshold value corresponds to a transition liquid outlet flow rate, which is the corresponding liquid outlet flow rate when the liquid to be sprayed is output from the liquid outlet in a dripping manner to a continuous spraying manner.

[0096] The following combination Fig.11 The structure of the liquid supply unit of the plurality of head units will be described in detail. Fig.11 Schematic diagram of a liquid supply unit of a plurality of spray head units according to some embodiments of the present invention is shown. Fig.11 As shown, the liquid supply unit 170 is used to provide the liquid to be sprayed for the nozzle unit group 172. The nozzle unit group 172 is, for example, composed of a plurality of nozzle units. The liquid supply unit 170 includes a liquid distributor 180, a plurality of flow limiting valves 190, a plurality of proportional valves 192 and connecting pipelines. The liquid distributor is used to distribute the liquid to be sprayed provided via the distributor inlet 182 to each flow limiting valve 192 via a plurality of distributor outlets 184. The liquid distributor 180 includes a distributor inlet 182 and a plurality of distributor outlets 184. The distributor inlet 182 is, for example, connected to a constant current source for receiving a constant current of the liquid to be sprayed. The plurality of distributor outlets 184 are respectively connected to a plurality of flow limiting valves 190. The flow limiting valve 190 is used to adjust the flow provided to the corresponding group of proportional valves 192 according to a control instruction (the control instruction is, for example, generated based on the density distribution data of the target object (e.g., fabric), and the density distribution data of the target object is, for example, provided by the supplier of the target object or generated based on the detection data for the target object). Each flow limiting valve 190 is respectively connected to a group of proportional valves 192. A group of proportional valves 192 includes, for example, a plurality of proportional valves. Fig.11As shown, each flow limiting valve 190 is respectively connected to a group of proportional valves 192 consisting of a first proportional valve 192-1 and a second proportional valve 192-2. Different proportional valves in the same group of proportional valves are respectively connected to different liquid inlets 150 in the same corresponding nozzle unit. For example, the first proportional valve 192-1 is connected to the first liquid inlet 150-1, and is used to adjust the liquid inlet flow rate of the first liquid inlet 150-1. The second proportional valve 192-2 is connected to the second liquid inlet 150-2, and is used to adjust the liquid inlet flow rate of the second liquid inlet 150-2. By adopting the above scheme, the present invention can not only conveniently supply liquid (for example, ink) to the nozzle unit group, but also enable the flow rate of the capillaries in different nozzle units to be individually controlled, thereby overcoming the problem of uneven coloring or spraying caused by uneven density in the width direction of the fabric.

[0097] The following combination Fig.12 The splicing method of multiple nozzle units is specifically described. Fig.12 Schematic diagram of a nozzle unit group according to some embodiments of the present invention is shown. Fig.12 As shown, the nozzle unit group 170 includes, for example, a plurality of nozzle units (for example, the nozzle unit group 170 includes a first nozzle unit 170-1, a second nozzle unit 170-2, and a third nozzle unit 170-3). The bottom plate 130 of each nozzle unit has, for example, a spliceable structure 129 for splicing with the bottom plate of an adjacent nozzle unit. In some embodiments, the spliceable structure 129 is, for example, one or more sets of mortise and tenon mechanisms. In other embodiments, the spliceable structure 129 is, for example, one or more sets of locking mechanisms.

[0098] By adopting the above method, the present invention can conveniently construct printing equipment of various widths, thereby meeting the coloring or spraying requirements of fabrics of different widths. It should be understood that Fig.12 The side walls and the bottom plate of any nozzle unit (for example, the second nozzle unit 170-2) can be independently installed and disassembled. Therefore, the present invention can conveniently perform independent maintenance and repair on the capillary of the nozzle unit (for example, the liquid outlet of the capillary is damaged or the capillary is blocked) without disassembling the entire nozzle unit.

[0099] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

[0100] The terms used in this document are selected to best explain the principles of the embodiments, practical applications or technical improvements in the marketplace, or to enable other ordinary technicians in this technical field to understand the embodiments disclosed herein.

[0101] The above specific implementations do not constitute a limitation on the protection scope of the present application. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made according to design requirements and other factors.

Claims

1. A nozzle for spraying a target object, characterized in that: It includes one or more nozzle units, each nozzle unit includes: A liquid supply unit, used for supplying the liquid to be sprayed to the flow channel; a flow channel, the flow channel being in communication with a flow channel connection port of each capillary in the capillary group; and One or more rows of capillary tube groups, each row of capillary tube groups includes multiple capillaries, each capillary tube includes a main body, a flow channel connection port and a liquid outlet, the flow channel connection port and the liquid outlet are respectively arranged at two ends of the main body, and the shape and size of the liquid outlet are configured so that the liquid to be sprayed is output from the liquid outlet in a continuous output manner.

2. The nozzle according to claim 1, characterized in that: The continuous output mode is a liquid column output mode.

3. The nozzle according to claim 1, characterized in that: The liquid supply unit comprises a plurality of liquid inlets, and the flow channel is configured to adjust the flow rates of the plurality of liquid inlets so that the flow rates of the liquid to be sprayed at the positions where the plurality of capillaries are located are different from each other.

4. The nozzle according to claim 1, characterized in that: The flow channel is configured as a longitudinal groove, the bottom surface of the longitudinal groove is an arc surface, an opening connected to the flow channel connection port of the capillary is arranged on the arc surface, and the height of the longitudinal groove is less than or equal to a predetermined height threshold.

5. The nozzle according to claim 1, characterized in that: The two ends of the main body of the capillary are respectively the flow channel connection end and the liquid outlet end, the outer diameter of the first end of the liquid outlet end is larger than the outer diameter of the second end of the liquid outlet end, the first end of the liquid outlet end is connected to the main body, and the second end of the liquid outlet end is provided with the liquid outlet.

6. The nozzle according to claim 5, characterized in that: The angle between the side wall of the liquid outlet end of the capillary and the radial cross section of the capillary is greater than or equal to 10 degrees.

7. The nozzle according to claim 5, characterized in that: The flow channel connection port is located at a first end of the flow channel connection end, and at least a portion of the liquid outlet end is configured as a tapered tube.

8. The nozzle according to any one of claims 5 to 7, characterized in that: The ratio of the inner diameter to the outer diameter of the second end of the liquid outlet is configured to be less than a predetermined range from a difference with a transition ratio threshold, and the transition ratio threshold corresponds to a transition liquid outlet flow rate, which is a corresponding liquid outlet flow rate when the mode of outputting the liquid to be sprayed from the liquid outlet is changed from a dripping mode to a continuous spraying mode.

9. The nozzle according to claim 1, characterized in that: The liquid supply unit also includes: a liquid distributor, comprising a distributor inlet and a plurality of distributor outlets; a plurality of flow limiting valves, wherein an input end of each flow limiting valve is connected to a corresponding distributor outlet of the plurality of distributor outlets; and There are multiple groups of proportional valves, and the output end of each flow limiting valve is connected to the corresponding group of proportional valves in the multiple groups of proportional valves.

10. The nozzle according to claim 9, characterized in that: The multiple proportional valves included in each group of proportional valves in the multiple groups of proportional valves are respectively connected to the multiple liquid inlets in the corresponding spray head unit.

11. The nozzle according to claim 1, characterized in that: Each sprinkler unit also includes: A bottom plate having a plurality of mounting holes for mounting the capillary tube set and defining the spacing between the capillaries; A flow channel plate, wherein one or more flow channels are arranged on a first surface of the flow channel plate; and The side wall, the bottom plate, and the second surface of the flow channel plate form a containing space for the capillary group.

12. The nozzle according to claim 5, characterized in that: Each sprinkler unit includes: A plurality of sealing rings, each of which is arranged on the outer side of the flow channel connecting end of the corresponding capillary tube, so as to seal the capillary tube.

13. The nozzle according to claim 12, characterized in that: The sealing ring is arranged in a sealing ring buckle groove on the second side of the flow channel plate, and the flow channel is arranged on the first surface of the flow channel plate.

14. The nozzle according to claim 11, characterized in that: The bottom plate of the nozzle unit has a splicable structure, which is used to realize the splicing between the bottom plates of adjacent nozzle units.

15. The nozzle according to claim 11, characterized in that: The shape, size, and distance between the liquid outlet and the target object are configured so that the liquid to be sprayed in a continuous liquid column section rather than a turbulent section where the liquid column changes into liquid droplets is provided to the target object.

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