Spray head for spraying target object

Abstract

The utility model relates to a spray head for spraying a target object. The spray head comprises spray head units, and each spray head unit comprises a liquid supply unit used for supplying to-be-sprayed liquid to a flow channel; the flow channel is communicated with the flow channel connecting port of each capillary tube in the capillary tube group; the 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 end, the liquid outlet end is located at one end of the main body part, a liquid outlet is formed in the liquid outlet end, and the shape and the size of the liquid outlet are configured to enable to-be-sprayed liquid to be output from the liquid outlet in a continuous output mode. According to the utility model, the manufacturing cost is lower, flying liquid discharge can be avoided, and the liquid spraying efficiency can be improved.

Description

Technical Field

[0001] The present utility model generally relates to inkjet printing technology, and specifically, to a nozzle for spraying a target object. Background Art

[0002] In existing nozzles for coloring or spraying a target object (such as a fabric), for example, ultrasonic atomization technology is used to atomize the liquid to be sprayed (such as ink) for printing on the target object. Since the atomization of the liquid to be sprayed requires additional energy consumption, and the atomized droplets (such as ink droplets) that are not attached to the target object need 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 precise controllability of the printed pattern, however, since they need to be equipped with a transducer for realizing ultrasonic atomization and an absorption device for absorbing excess atomized ink droplets, the manufacturing cost is relatively high. In addition, the efficiency of atomized liquid spraying for coloring or spraying is not good.

[0003] In summary, the deficiencies of traditional nozzles are as follows: they have a relatively high manufacturing cost, there is a problem of flying liquid (such as flying ink) emission, and the spraying efficiency of the liquid to be sprayed (such as inkjet) is not good. Summary of the Utility Model

[0004] The present utility model provides a nozzle for spraying a target object, which can have a relatively low manufacturing cost, and can avoid flying liquid emission and improve the spraying efficiency.

[0005] According to a first aspect of the present utility model, there is provided a nozzle for spraying a target object, the nozzle including a nozzle unit, and each nozzle unit including: a liquid supply unit for supplying a liquid to be sprayed to a flow channel; a flow channel, the flow channel communicating with a flow channel connection port of each capillary in a capillary group; and a capillary group including a plurality of capillaries, each capillary including a main body portion, a flow channel connection port, and a liquid outlet end, the liquid outlet end being located at one end of the main body portion and having a liquid outlet provided thereon, the shape and size of the liquid outlet being configured such that the liquid to be sprayed is output from the liquid outlet in a continuous output manner.

[0006] In some embodiments, the continuous output manner is a liquid column output manner.

[0007] In some embodiments, the liquid supply unit includes a plurality of liquid inlet ports, and the flow channel is configured to make the flow rates of the liquid to be sprayed at the positions of the plurality of capillaries different by adjusting the flow rates of the plurality of liquid inlet ports.

[0008] In some embodiments, the flow channel is configured as a longitudinal groove, the bottom surface of the longitudinal groove is an arc surface, and an opening communicating with 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 other end of the main body portion of the capillary tube is a flow channel connection end, the outer diameter of the first end of the liquid outlet end is greater 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 portion, and the second end of the liquid outlet end is provided with the liquid outlet.

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

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

[0012] In some embodiments, the ratio of the inner diameter to the outer diameter of the second end of the liquid outlet end is configured such that the difference from the transition ratio threshold is less than a predetermined range, the transition ratio threshold corresponds to a transition liquid outlet flow rate, and the transition liquid outlet flow rate is the corresponding liquid outlet flow rate when the liquid to be sprayed changes from a dripping mode to a continuous spraying mode at the liquid outlet.

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

[0014] In some embodiments, each group of proportional valves included in the multiple groups of proportional valves is respectively communicated with a plurality of liquid inlet ports in the corresponding nozzle unit.

[0015] In some embodiments, each nozzle unit further includes: a bottom plate, having a plurality of mounting holes for mounting a capillary tube group and defining the spacing between the capillary tubes; a flow channel plate, with one or more of the flow channels configured on the first surface of the flow channel plate; and a side wall, where the side wall, the bottom plate, and the second surface of the flow channel plate form a receiving space for the capillary tube group.

[0016] In some embodiments, each nozzle unit includes: a plurality of sealing rings, and each sealing ring among the plurality of sealing rings is disposed outside the flow channel connection end of the corresponding capillary tube for sealing 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 splicing structure for realizing the splicing between the bottom plates of adjacent nozzle units.

[0019] In some embodiments, the shape, size of the liquid outlet, and the distance between the liquid outlet and the target object are configured such that the liquid to be sprayed, which is in the continuous liquid column section rather than the turbulent section where the liquid column becomes droplets, is provided onto the target object.

[0020] The Brief Description of the Utility Model is provided to introduce, in a simplified form, a selection of concepts that will be further described in the Detailed Description below. The Brief Description of the Utility Model is not intended to identify the key features or main features of the present utility model, nor is it intended to limit the scope of the present utility model. Brief Description of the Drawings

[0021] Figure 1 A longitudinal sectional view of a nozzle head for spraying a target object according to some embodiments of the present utility model is shown.

[0022] Figure 2 A side view of the accommodation space of a capillary group according to some embodiments of the present utility model is shown.

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

[0024] Figure 4 A transverse sectional view of a nozzle head unit according to some embodiments of the present utility model is shown.

[0025] Figure 5 A bottom view of a nozzle head unit according to some embodiments of the present utility model is shown.

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

[0027] Figure 7 A sectional view of a partial capillary according to some embodiments of the present utility model is shown.

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

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

[0030] Figure 10 A schematic diagram of continuous output and dripping output modes according to some embodiments of the present utility model is shown.

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

[0032] Figure 12Shows a schematic diagram of a nozzle unit group according to some embodiments of the present utility model.

[0033] In the respective drawings, the same or corresponding reference numerals denote the same or corresponding parts. Detailed implementation manners

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

[0035] As used herein, the term "comprising" and its variations denote open-ended inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "at least partially based 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 deficiencies of traditional nozzles are: having a relatively high manufacturing cost and having the problem of liquid splash discharge.

[0037] To at least partially solve one or more of the above problems and other potential problems, example embodiments of the present utility model propose a nozzle for spraying a target object, by making the nozzle include nozzle units, each nozzle unit including: a liquid supply unit for supplying a liquid to be sprayed to a flow channel; a flow channel, the flow channel communicating with the flow channel connection ports of each capillary in a 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 portion, a flow channel connection port, and a liquid outlet, the flow channel connection port and the liquid outlet being respectively provided at two ends of the main body portion, the shape and size of the liquid outlet being configured such 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 utility model significantly reduces the manufacturing cost, has a higher liquid spraying efficiency, and does not generate liquid splash. Therefore, the present utility model can have a lower manufacturing cost and can avoid liquid splash discharge.

[0038] The following is combined with Figure 1 Exemplarily illustrate the nozzle 100 for spraying a target object. Figure 1 Shows a longitudinal sectional view of the nozzle 100 for spraying a target object according to some embodiments of the present utility model.

[0039] The nozzle 100 includes, for example, a nozzle unit. Figure 1 Exemplarily shown is a nozzle including one nozzle unit. As Figure 1 shown, each nozzle unit includes a liquid supply unit, a flow channel 110, and one or more rows of capillary groups 120 ( Figure 1 two rows of capillary groups are exemplified).

[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 manner of a constant current source, for example. In some embodiments, the liquid supply unit includes a plurality of liquid inlets 150. As Figure 1 shown, each nozzle unit includes, for example, 3 liquid inlets 150 (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). In some embodiments, the liquid supply unit of each nozzle unit includes, for example, two liquid inlets 150, as Figure 11 shown. It should be understood that the liquid supply unit may also include other numbers of liquid inlets.

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

[0042] Regarding the flow channel 110, it is used to supply the liquid to be sprayed from the liquid supply unit to the capillary group 120. The flow channel 110 communicates with the flow channel connection ports of each capillary in the capillary group 120. Figure 1 Only the part of the flow channel 110 exposed by the liquid inlet 150 is schematically shown in

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

[0044] Regarding the capillary group 120, it is used to output the liquid to be sprayed from the flow channel onto the target object. Each nozzle unit includes one or more rows of capillary groups 120. Each row of capillary groups 120 includes a plurality of capillaries. Each capillary includes: a main body part, 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 part, and the shape and size of the liquid outlet are configured such that the liquid to be sprayed is output from the liquid outlet in a continuous output manner. Regarding the continuous output manner, it is, for example, a liquid column output manner, rather than a non-continuous manner similar to liquid droplets. It should be understood that since the liquid to be sprayed is output from the liquid outlet in a continuous output manner, the spraying efficiency of the present utility model can be significantly improved.

[0045] Regarding the continuous output manner, it is, for example, a continuous liquid column output manner. Figure 10Schematic diagrams showing continuous output and drip output according to some embodiments of the utility model are shown. Figure 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. Figure 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. Figure 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 output 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 utility model are configured so that the liquid to be sprayed is discharged in a non-continuous manner. Figure 10 In some embodiments, the shape, size, and distance between the liquid outlet and the target object of the utility model 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. Figure 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 utility model. Figure 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 Figure 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 Figure 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 Figure 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 Figure 9 Medium Z1 Indicates the inductive reactance of the first capillary; L ZNIndicating the inductive reactance of the Nth capillary). Additionally, each group of flow channel sections and capillaries also has a "capacitive reactance" exhibited by the gas-liquid (the capacitive reactance indicates the storage amount of the fluid exhibited by the gas-liquid, such as Figure 9 where 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). Additionally, Figure 9 where I L indicates a constant current source connected to one end (e.g., the left end) of the flow channel; I M indicates a constant current source connected to the middle of the flow channel (which is connected near the N / 2th capillary, for example); I R indicates a constant current source connected to the other end (e.g., the right end) of the flow channel. As Figure 9 shown, one ends of the three constant current sources are connected and "grounded" (as Figure 9 the inverted triangle in 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 rate. "Grounding" is equivalent to being connected to the atmospheric pressure. It should be understood that the liquid outlet of each capillary is connected to the atmospheric pressure, so one end of the capillary is equivalent to being "grounded".

[0047] The calculation methods of inductive reactance, capacitive reactance, and flow resistance are respectively exemplarily described below 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. l LN represents the length of the Nth flow channel section. A R represents the cross-sectional area of the Nth flow channel section (taking the 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 section and the Nth capillary. B represents the bulk modulus of the Nth flow channel section and the Nth capillary.

[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. l LN represents the length of the Nth flow channel section. rLN Represents the radius of the cross-section of the Nth flow channel section (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 section has a relatively large impact on the flow resistance. A small change in the radius will bring a significant change in the flow resistance. It should be understood that the calculation method of the flow resistance of the capillary is similar. In addition, formulas (1) to (3) take the flow channel and / or capillary with a circular cross-section as an example. The cross-sections of the flow channel and the capillary can also be other shapes.

[0054] In some embodiments, the flow resistance of the flow channel is configured to make the flow rates of the liquid to be sprayed at the positions of multiple capillaries different by adjusting the flow rates of multiple liquid inlets. For example, Figure 9 I in L Indicates a constant current source connected to one end (e.g., the left end) of the flow channel, which is connected to, for example, the first liquid inlet 150-1 located on the left side of the flow channel. Figure 9 I in M Indicates a constant current source connected to the middle of the flow channel, which is connected to, for example, the second liquid inlet 150-2 located in the middle of the flow channel. Figure 9 I in 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 the steady state, by separately controlling the liquid inlet flow rates 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, a linear change in the flow rate at the capillary can be achieved. For example, the flow rates at each capillary gradually change from left to right. For 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 a predetermined value; the liquid inlet flow rate of the second liquid inlet 150-2 located in the middle of the flow channel is -100% 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 100% of the predetermined value. At this time, the phenomenon that the liquid inlet flow rates at both ends of the flow channel are high flow rates and the liquid inlet flow rate in the middle is a low flow rate is caused, 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 a 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, during the spray dyeing process of a fabric, before the fabric enters the printing area, due to the pretreatment process, the fabric will show a non-uniform density state across the entire width. If the application amount of the dyeing liquid (i.e., the liquid to be sprayed) is the same during printing, it will cause uneven final coloring of the fabric. The present utility model controls the liquid inlet flow rates of multiple liquid inlets at different positions of the flow channel to achieve different liquid outlet flow rates (e.g., linear change) at different capillaries, so that for the non-uniform density state of the fabric across the entire width, different flow rates of the liquid to be sprayed are output at different capillaries, thereby achieving uniform coloring or spraying of the entire fabric.

[0055] Regarding the main body part of the capillary (as Figure 4 indicated by the label 126 in Figure 4 ), it is, for example, an elongated circular tubular shape. The two end portions at both ends of the main body part are respectively a flow channel connection end (as

[0056] indicated by the label 124 in Figures 6 to 8 and a liquid outlet end 122. Figure 6 Shows a partially enlarged view of a capillary according to some embodiments of the present utility model. Figure 7 Shows a cross-sectional view of a part of a capillary according to some embodiments of the present utility model. Figure 8 Shows a schematic structural view of a capillary according to some embodiments of the present utility model. As Figure 6As shown, one end of the main body portion 126 of the capillary tube is the liquid outlet end 122. The first end 127 of the liquid outlet end 122 is connected to the main body portion 126, and the second end 128 of the liquid outlet end 122 is the liquid outlet.

[0057] In some embodiments, the outer diameter of the first end 127 of the liquid outlet end 122 (e.g., as indicated by "DN" in Figure 7 and Figure 8 ) is greater than the outer diameter of the second end 128 of the liquid outlet end 122 (e.g., as indicated by "D" in Figures 6 to 8 ). Thus, it is beneficial to control the liquid flow rate at the liquid outlet. It should be understood that the outer diameter DN of the first end 127 of the liquid outlet end 122 is the outer diameter of the capillary tube. In some embodiments, the outer diameter of the capillary tube 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, as shown in Figure 7 . In some embodiments, the inner diameter (dn) of the first end 127 of the liquid outlet end 122 is greater than the inner diameter (d) of the second end 128 of the liquid outlet end 122, as shown in Figure 8 . In some 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, for example, as an arc shape, a stepped shape, or segmented. In some embodiments, at least a part of the liquid outlet end 122 is configured, for example, as a tapered tube. As shown in Figure 7 , the entire liquid outlet end 122 is configured, for example, as a tapered tube. It should be understood that the outer diameter of the tapered tube gradually decreases, and the inner diameter of the tapered tube can remain unchanged or gradually decrease. For example, as shown in Figure 7 , in the direction of 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 decreases 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 an unchanged inner diameter, it is beneficial to control the liquid flow rate at the liquid outlet and facilitate processing.

[0060] Figure 8The cross-sectional view in the upper right corner in [text] is an enlarged view of the area enclosed by the circle indicated by reference numeral 121. As Figure 8 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) and the inner diameter (dn) at the first end 127 may or may not be equal to the difference between the outer diameter (D) and the inner diameter (d) at 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 at 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 both the outer and inner diameters decreasing, it is beneficial to more effectively control the liquid flow rate at the liquid outlet. Regarding the side wall of the liquid outlet end of the capillary tube, in some embodiments, as Figure 7 shown, the angle θ between the side wall 810 of the liquid outlet end of the capillary tube and the radial cross-section 812 of the capillary tube 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 angle range, it is possible to prevent the liquid output from the liquid outlet from wetting the side surface of the liquid outlet end, so as to facilitate the formation of a continuous liquid column. It should be understood that if the liquid output from the liquid outlet wets the side surface of the liquid outlet end, it is likely to form an asymmetric wetting condition, which will have a negative impact on the formation of a continuous liquid column output from the liquid outlet.

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

[0062] The relationship between the inner diameter d and the outer diameter D of the liquid outlet and the critical Weber number will be described below in conjunction with formulas (4) to (6).

[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 numbers based on the inner diameter and outer diameter of the liquid outlet, respectively. K represents a constant. The ratio of B0 to 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 due to gravity. v0 represents the flow velocity of the liquid to be sprayed. D represents the inner diameter (diameter) of the capillary of the liquid outlet. It should be understood that the Weber number is a characteristic number applied in fluid mechanics, which characterizes the ratio of the deformation inertial force to the stable cohesive force when a liquid (e.g., the liquid to be sprayed) flows through a fluid medium (e.g., a capillary). The cohesive force is related to the surface tension or the interfacial tension, which will prevent the increase of the surface area, thus causing deformation. Therefore, the droplets of the liquid to be sprayed will gather together due to the surface tension or the interfacial tension. The critical Weber number indicates the Weber number at which the liquid to be sprayed with density ρ and surface tension σ flows through the liquid outlet with inner diameter D at flow velocity v0 and is output from the liquid outlet in a manner from droplet mode to continuous jet mode (or "continuous output mode", e.g., a liquid column). It should be understood that the critical Weber number is associated with the transitional flow rate related to the transition of the output mode of the liquid to be sprayed from the droplet mode to the continuous jet mode at the liquid outlet.

[0067] Regarding the transitional flow rate, for example, it is the flow rate at which the output mode of the liquid to be sprayed from the liquid outlet changes from Figure 10 the droplet mode (or "droplet output mode") shown in the right part to Figure 10 the continuous jet mode (or "continuous output mode", or "liquid column mode") shown in the left part.

[0068] Research shows that when the inner diameter of the capillary (e.g., the inner diameter of the liquid outlet end is equal to the inner diameter of the capillary) is small enough, the interface of the liquid to be sprayed can be stabilized to the Rayleigh - Taylor instability (RT instability for short). In this state, the inertia of the liquid to be sprayed, the capillary action of the capillary, and the gravitational action 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 remains unchanged, the closer the outer diameter D is to the inner diameter d (i.e., the smaller the outer diameter D), the smaller the transitional flow rate for the liquid to be sprayed output from the liquid outlet to change from the droplet mode to the continuous jet mode. In some embodiments, the ratio of the inner diameter to the outer diameter of the second end of the liquid outlet end is configured such that the difference from the transitional ratio threshold is less than a predetermined range, and the transitional ratio threshold corresponds to the transitional liquid output flow rate, and the transitional liquid output flow rate is the corresponding liquid output flow rate when the output mode of the liquid to be sprayed from the liquid outlet changes from the droplet mode to the continuous jet mode.

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

[0070] Regarding the bottom plate 130, it has a plurality of mounting holes for mounting the capillary group 120 and for defining the spacing between the capillaries.

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

[0072] Regarding the side walls 132, they form a receiving space for the capillary group 120 together with the bottom plate 130 and the second surface of the flow channel plate 134. In some embodiments, the side walls 132 include, for example, at least a first side wall 132-1 and a second side wall 132-2 (as Figure 2 shown in Figure 2 ).

[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. As Figure 1 shown in Figure 1 , each sealing ring is disposed outside the flow channel connection end of the corresponding capillary for sealing the capillary. Figure 1 The part within the virtual line indicated by the marker 102 in the upper left dashed box is a partial enlarged view, where it is indicated that each sealing ring 140 is sleeved outside the flow channel connection end of the corresponding capillary. And the sealing ring is disposed in the sealing ring snap groove on the second side of the flow channel plate 134.

[0074] In some embodiments, each nozzle 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, for example, to be located on the upper surface of the nozzle unit. In some embodiments, the top plate 138 is used to mount 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 for sealing the communication space between the flow channel and the liquid inlet 150. In some embodiments, both the sealing plate 136 and the top plate 138 are provided with through holes (e.g., Figure 2 the top plate through hole 139 and the sealing plate through hole 137 shown in Figure 2 ) communicating with the liquid inlet 150 to guide the liquid to be sprayed from the liquid inlet 150 to the flow channel 110.

[0077] Regarding the mounting plate 142, which is disposed, for example, 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 Figure 2 Exemplarily illustrates a schematic diagram of the accommodation space of the capillary tube group. Figure 2 Shows a side view of the accommodation space of the capillary tube group according to some embodiments of the present invention.

[0079] Regarding the accommodation space 135 of the capillary tube group, in some embodiments, as Figure 2 shown, it is defined, for example, at least by the side wall 132 (the side wall 132 specifically includes a first side wall 132-1 and a 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, an accommodation space 135 of a capillary tube group. Each accommodation space 135 of the capillary tube group accommodates, for example, one row or multiple rows of capillary tube groups. As Figure 2 shown, the accommodation space 135 of the capillary tube group accommodates two rows of capillary tube groups.

[0080] The following Figure 3 Exemplarily illustrates a schematic diagram of the flow channel plate 134. Figure 3 Shows a top view of the flow channel plate according to some embodiments of the present invention.

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

[0082] The first surface of the flow channel plate 134 is configured with a plurality of flow channels 110, for example. Figure 3 Schematically shows that the first surface of the flow channel plate 134 includes 2 flow channels. It should be understood that the number of flow channels 110 configured on the flow channel plate 134 of each nozzle unit is equal to the number of rows of the capillary tube group, and each flow channel 110 is used to provide the liquid to be sprayed for the corresponding row of capillary tubes 120. Each flow channel 110 includes, for example, a plurality of openings, and the flow channel is connected to the flow channel connection port of the corresponding capillary tube in the capillary tube group through the opening. In some embodiments, the flow channel plate 134 is further provided with a plurality of mounting holes 114 to achieve 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 make the flow rates of the liquid to be sprayed at the positions of the multiple capillary tubes different by adjusting the flow rates of the multiple liquid inlets. As 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 to make the liquid to be sprayed have different liquid outlet flow rates at the position of the Mth capillary and the position of the Nth capillary among multiple capillaries by adjusting the flow rates of multiple liquid inlets, for example.

[0084] In some embodiments, the flow channel 110 is configured as a longitudinal groove, for example. The bottom surface of the longitudinal groove is an arc surface, and openings communicating with the flow channel connection ports of the capillaries are provided on the arc surface. It should be understood that by setting the bottom surface of the flow channel 110 as an arc surface, the flow channel of the present invention can reduce the residue of the liquid to be sprayed in the flow channel.

[0085] Regarding the longitudinal groove, it is, for example, a long and narrow shallow groove extending along Figure 3 the X direction therein. In some embodiments, the cross-section of the longitudinal groove is semi-circular. 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 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 1 mm, for example.

[0086] It should be understood that at 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 configured to be less than a predetermined cross-sectional area threshold, for example. 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 requirement for controlling the flow rate of the liquid to be sprayed by the nozzle. It should be understood that the flow resistance in microfluidics is mainly caused by the pressure drop and energy loss due to the friction between the liquid and the channel wall. Experimental data shows that when the viscous liquid to be sprayed is in a laminar flow state, the closer the liquid to be sprayed is to the flow channel wall, the greater its flow resistance and the lower the corresponding flow rate; under the same pressure, the smaller the inner diameter size 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 long and narrow shallow groove and making its cross-sectional size small enough, thereby improving the sensitivity of the flow rate control of the liquid to be sprayed by the nozzle.

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

[0089] As Figure 3 and Figure 4 shown, mounting holes are provided on the bottom plate 130. Mounting holes are provided on the mounting plate 142. Mounting holes are also provided on the side wall 132. 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, so as to realize the fixation between the bottom plate 130, the side wall 132 and the mounting plate 142.

[0090] As Figure 4 shown, through the coupling of 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, the relative fixation between the top plate 138, the sealing plate 136, the flow channel plate 134 and the mounting plate 142 is realized.

[0091] In some embodiments, the first mounting device 144 and the second mounting device 146 are configured in the form of bolts, for example. In some embodiments, coupling and decoupling can be achieved between the first mounting device 144 and the second mounting device 146.

[0092] It should be understood that through the above mounting method, the utility model is convenient for realizing local maintenance and installation. For example, by decoupling the first mounting device 144 from the mounting holes on the bottom plate 130, the side wall 132 and the mounting plate 142, the disassembly of the bottom plate 130 and the side wall 132 can be conveniently realized, so as to facilitate the installation and maintenance of the capillary tube 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, by decoupling the second mounting device 146 from the mounting holes on the top plate 138, the sealing plate 136, the flow channel plate 134 and the mounting plate 142, the disassembly of the top plate 138, the sealing plate 136 and the flow channel plate 134 can be conveniently realized, so as to facilitate 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 tube group.

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

[0094] Figure 4The second surface 118 of the flow channel plate 134 is also shown to be configured 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 The bottom view of the nozzle unit according to some embodiments of the present invention is shown.

[0095] In some embodiments, the ratio of the inner diameter to the outer diameter of the second end of the liquid outlet end is configured to have a difference from the transition ratio threshold that is less than a predetermined range. The transition ratio threshold corresponds to a transition liquid outlet flow rate, and the transition liquid outlet flow rate is the corresponding liquid outlet flow rate when the liquid to be sprayed changes from the dripping mode to the continuous spraying mode at the liquid outlet.

[0096] The following combines Figure 11 Specifically describe the structure of the liquid supply unit of multiple nozzle units. Figure 11 The schematic diagram of the liquid supply unit of multiple nozzle units according to some embodiments of the present invention is shown. As Figure 11 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, formed by splicing multiple nozzle units. The liquid supply unit 170 includes a liquid distributor 180, multiple flow limiting valves 190, multiple groups of proportional valves 192, and connecting pipelines. The liquid distributor is used to distribute the liquid to be sprayed provided through the distributor inlet 182 to each flow limiting valve 192 through multiple distributor outlets 184. The liquid distributor 180 includes a distributor inlet 182 and multiple distributor outlets 184. The distributor inlet 182 is, for example, connected to a constant current source and is used to receive the liquid to be sprayed with a constant current. The multiple distributor outlets 184 are respectively connected to the multiple flow limiting valves 190. The flow limiting valve 190 is used to adjust the flow rate 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 (such as 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, for example, includes multiple proportional valves. As Figure 11As shown, each flow-limiting valve 190 is respectively connected to a group of proportional valves 192 composed 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 corresponding same nozzle unit. For example, the first proportional valve 192-1 is connected to the first liquid inlet 150-1 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 to adjust the liquid inlet flow rate of the second liquid inlet 150-2. By adopting the above solution, the utility model can not only conveniently supply liquid (such as ink) to the nozzle unit group, but also enable the flow rates of the capillaries in different nozzle units to be controlled separately, thereby overcoming the problem of uneven coloring or spraying caused by uneven density in the width direction of the fabric.

[0097] The following will specifically describe the splicing method of multiple nozzle units in conjunction with Figure 12 Specifically describe the splicing method of multiple nozzle units. Figure 12 FIG. shows a schematic diagram of a nozzle unit group according to some embodiments of the present utility model. As Figure 12 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 splicing structure 129 for splicing with the bottom plate of an adjacent nozzle unit. In some embodiments, the splicing structure 129 is, for example, one or more groups of tenon-and-mortise mechanisms. In other embodiments, the splicing structure 129 is, for example, one or more groups of buckle mechanisms.

[0098] By adopting the above method, the present utility model can conveniently construct printing devices of various widths, thereby meeting the coloring or spraying requirements of fabrics with different widths. It should be understood that Figure 12 the side wall and the bottom plate of any nozzle unit (such as the second nozzle unit 170-2) can be independently installed and disassembled. Thus, the present utility model can conveniently perform independent maintenance and repair on the capillaries of the nozzle unit (for example, the liquid outlet of the capillary is damaged or the capillary is blocked), without having to disassemble the entire nozzle unit.

[0099] The above has described the embodiments of the present utility model. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art in the technical field without departing from the scope and spirit of the described embodiments.

[0100] The selection of the terms used herein is intended to best explain the principles, practical applications, or improvements in the technology in the market of each embodiment, or to enable other ordinary technical personnel in the technical field to understand the embodiments disclosed herein.

[0101] The above specific embodiments do not constitute a limitation on the protection scope of this application. Those skilled in the art should understand that various modifications, combinations, sub - combinations and substitutions can be made according to design requirements and other factors.

Claims

1. A nozzle for spraying a target object, characterized in that, including a nozzle unit, the nozzle unit comprising: a liquid supply unit for supplying a liquid to be sprayed to a flow channel; a flow channel that communicates with a flow channel connection port of each capillary in a capillary group; and a capillary group including a plurality of capillaries, each capillary including a main body portion, a flow channel connection port, and a liquid outlet end. The liquid outlet end is located at one end of the main body portion, and a liquid outlet is provided on the liquid outlet end. The shape and size of the liquid outlet are configured such 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 manner is a liquid column output manner.

3. The showerhead according to claim 1, wherein The liquid supply unit includes a plurality of liquid inlet ports, and the flow channel is configured to make the flow rates of the liquid to be sprayed at the positions of the plurality of capillaries different from each other by adjusting the flow rates of the plurality of liquid inlet ports.

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, and an opening communicating with the flow channel connection port of the capillary is provided on the arc surface. The height of the longitudinal groove is less than or equal to a predetermined height threshold.

5. The spray head according to claim 1, wherein The other end of the main body portion of the capillary is a flow channel connection end. The outer diameter of the first end of the liquid outlet end is greater 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 portion, 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 showerhead according to claim 5, wherein The flow channel connection port is located at the first end of the flow channel connection end, and at least a part of the liquid outlet end is configured as a tapered tube.

8. The shower head 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 end is configured such that the difference from a transition ratio threshold is less than a predetermined range. The transition ratio threshold corresponds to a transition liquid outlet flow rate, and the transition liquid outlet flow rate is the corresponding liquid outlet flow rate when the output manner of the liquid to be sprayed from the liquid outlet changes from a dripping manner to a continuous spraying manner.

9. The showerhead according to claim 1, wherein, The liquid supply unit further includes: a liquid distributor including a distributor inlet and a plurality of distributor outlets; a plurality of flow restrictors, the input end of each flow restrictor communicating with a corresponding distributor outlet among the plurality of distributor outlets; and a plurality of groups of proportional valves, the output end of each flow restrictor communicating with a corresponding group of proportional valves among the plurality of groups of proportional valves.

10. The nozzle according to claim 9, characterized in that, Each of the plurality of groups of proportional valves included in each group of proportional valves communicates with a plurality of liquid inlet ports in a corresponding nozzle unit.

11. The showerhead according to claim 1, characterized in that, Each nozzle unit further includes: a bottom plate having a plurality of mounting holes for mounting the capillary group and defining the spacing between the capillaries; a flow channel plate having one or more of the flow channels disposed on a first surface of the flow channel plate; and a side wall that forms a receiving space for the capillary group with the bottom plate and a second surface of the flow channel plate.

12. The nozzle according to claim 5, characterized in that, Each nozzle unit includes: a plurality of sealing rings, each of the plurality of sealing rings being disposed outside the flow channel connection end of a corresponding capillary for sealing the capillary.

13. The showerhead according to claim 12, characterized in that, 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 disposed on the first surface of the flow channel plate.

14. The spray head according to claim 11, wherein, The bottom plate of the nozzle unit has a splicing structure for realizing splicing between the bottom plates of adjacent nozzle units.

15. The spray head according to claim 11, characterized in that, The shape, size, and the distance between the liquid outlet and the target object are configured such that the liquid to be sprayed, which is in the continuous liquid column section rather than the turbulent section where the liquid column becomes droplets, is provided onto the target object.

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