Manufacturing method of nozzle, nozzle and spraying device

Abstract

The invention belongs to the technical field of fluid jetting, and discloses a nozzle manufacturing method, a nozzle and a jetting device. The manufacturing method of the nozzle comprises the following steps: S1, providing a capillary glass tube, vertically suspending the capillary glass tube, and arranging an electric heating wire on the periphery of the lower end part of the capillary glass tube; s2, the electric heating wire is used for heating to soften the capillary glass tube, the lower end part of the capillary glass tube converges into a spherical shape or a water drop shape, and the lower end part of the capillary glass tube is continuously observed; s3, stopping heating when the lower end part of the capillary glass tube forms a taper angle with a preset angle, and cutting the capillary glass tube according to a preset cutting line after the capillary glass tube is cooled; and S4, the cut section is subjected to polishing treatment. According to the manufacturing method, the wall thickness of the nozzle is increased; the taper of the nozzle can reach a preset angle, and the viscous resistance of fluid under a micro scale is effectively reduced, so that the spraying efficiency and the performance of the nozzle are obviously improved; and the section of the nozzle subjected to polishing treatment is smooth and round, so that the flowing smoothness of fluid is ensured.

Description

Technical Field

[0001] The present invention relates to the field of fluid injection technology, and in particular to a nozzle manufacturing method, a nozzle and an injection device. Background Art

[0002] Precision fluid injection technology is a new method for manufacturing micro-nano structures and devices, and is widely used in the micro-manufacturing of micro-electromechanical systems, micro-mechanical components and pharmaceutical materials. Precision fluid injection is usually completed using an extrusion injection device, which works by causing the fluid coated by the piezoelectric material to generate pressure waves through the contraction or expansion of the piezoelectric material, and finally ejecting micro droplets from the nozzle.

[0003] In the prior art, nozzles are usually formed by heating and then stretching a capillary glass tube. Although the diameter requirement of the nozzle can be met, the nozzle taper obtained by this manufacturing method is very small, and the fluid viscosity resistance at a micro scale is large, resulting in difficulty in ejecting microdroplets; and the nozzle obtained by stretching has low mechanical strength and is easily damaged.

[0004] Therefore, it is necessary to provide a method for manufacturing a nozzle, a nozzle and a spraying device to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a method for manufacturing a nozzle, a nozzle and an injection device, wherein the cone angle of the manufactured nozzle can reach a preset angle, reducing the viscous resistance of the fluid at a microscale, and the wall thickness of the nozzle is relatively thick and not easily damaged.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] A method for manufacturing a nozzle, comprising:

[0008] S1. Provide a capillary glass tube, suspend the capillary glass tube vertically, and arrange an electric heating wire around the outer periphery of the lower end thereof;

[0009] S2, the electric heating wire is heated to soften the capillary glass tube, and the lower end of the capillary glass tube is gathered into a spherical or teardrop shape, and the lower end of the capillary glass tube is continuously observed;

[0010] S3, when the lower end of the capillary glass tube forms a cone angle of a preset angle, the heating is stopped, and after the capillary glass tube is cooled, the capillary glass tube is cut according to a preset cutting line;

[0011] S4. Polishing the cut section.

[0012] Preferably, in step S2, an observation device is used to observe the lower end of the capillary glass tube.

[0013] Preferably, in step S3, the preset angle is 65°-90°.

[0014] Preferably, in step S3, after cutting according to the preset cutting line, the opening diameter of the capillary glass tube is 10 μm-200 μm.

[0015] Preferably, step S4 specifically includes:

[0016] S401, grinding the cross section;

[0017] S402, flame polishing the cross section.

[0018] Preferably, the manufacturing method further comprises:

[0019] S5. Coating a polytetrafluoroethylene coating on the inner surface of the capillary glass tube.

[0020] A nozzle is manufactured by the nozzle manufacturing method described above.

[0021] A spraying device, comprising:

[0022] A liquid storage tube, the interior of which is filled with fluid for injection;

[0023] The above-mentioned nozzle is arranged at one end of the liquid storage tube and is connected to the liquid storage tube;

[0024] The piezoelectric ceramic tube is sleeved outside the liquid storage tube, the inner wall surface of the piezoelectric ceramic tube is connected to the inner electrode, and the outer wall surface of the piezoelectric ceramic tube is connected to the outer electrode.

[0025] Preferably, the injection device further comprises:

[0026] A fluid circuit connector is disposed at the other end of the liquid storage tube and is in communication with the liquid storage tube. A fluid replenishment tube is connected to the liquid storage tube through the fluid circuit connector to replenish the fluid to the liquid storage tube.

[0027] Preferably, the piezoelectric ceramic tube is located in the middle of the liquid storage tube.

[0028] Beneficial effects of the present invention:

[0029] The manufacturing method of the nozzle includes: S1, providing a capillary glass tube, hanging the capillary glass tube vertically, and arranging an electric heating wire on the outer periphery of the lower end thereof; S2, heating the capillary glass tube with the electric heating wire to soften the capillary glass tube, and the lower end of the capillary glass tube will converge into a sphere or a teardrop shape, and the lower end of the capillary glass tube is continuously observed; S3, stopping heating when the lower end of the capillary glass tube forms a cone angle of a preset angle, and cutting the capillary glass tube according to a preset cutting line after the capillary glass tube is cooled; S4, polishing the cut section.

[0030] The capillary glass tube is suspended vertically, and a heating wire is arranged on the outer periphery of the lower end thereof. By controlling the temperature of the heating wire, the capillary glass tube surrounded by the heating wire can be heated and softened. Since the capillary glass tube is in a suspended state, the softened part will gather into a sphere or a water drop shape under the action of surface tension and gravity, and it is very easy to form a cone angle of a preset angle, and then the heating is stopped and cooled, and the capillary glass tube is cut according to the preset cutting line to obtain the required nozzle diameter, that is, the preset cutting line is set according to the required nozzle diameter, and the cross section after cutting is polished to make the cross section smoother and rounder. The nozzle obtained by this manufacturing method is an inner cone. Compared with the traditional nozzle formed by stretching, this manufacturing method significantly increases the wall thickness of the nozzle, making it more durable and not easy to be damaged; this manufacturing method can easily make the nozzle taper reach a preset angle, effectively reduce the viscous resistance of the fluid at a micro scale, and increase the speed of the fluid when leaving the nozzle, thereby significantly improving the nozzle The injection efficiency and performance; the polished nozzle cross section is smooth and round, further ensuring the smoothness of the fluid flow.

[0031] This nozzle is made by the above-mentioned nozzle manufacturing method. The wall thickness of this nozzle is relatively thick, and it is durable and not easy to be damaged. This nozzle effectively reduces the viscous resistance of the fluid at a microscopic scale and increases the speed of the fluid when leaving the nozzle, thereby significantly improving the nozzle's injection efficiency and performance. This nozzle can be used to spray picoliter-scale tiny droplets.

[0032] This spraying device includes a liquid storage tube, a nozzle made by the above-mentioned nozzle manufacturing method and a piezoelectric ceramic tube. The liquid storage tube is filled with fluid for spraying. The nozzle is arranged at one end of the liquid storage tube and is connected to the liquid storage tube. The piezoelectric ceramic tube is sleeved outside the liquid storage tube. The inner wall surface of the piezoelectric ceramic tube is connected to the inner electrode, and the outer wall surface of the piezoelectric ceramic tube is connected to the outer electrode. During operation, a pulse voltage is applied between the inner electrode and the outer electrode. The piezoelectric ceramic tube expands back under the action of the pulse voltage to squeeze the liquid storage tube so that the fluid in the liquid storage tube is ejected from the nozzle. By utilizing the rapid expansion characteristics of the piezoelectric ceramic tube under the action of the pulse voltage, the liquid storage tube can be squeezed accurately and efficiently, thereby driving the fluid in the liquid storage tube to be ejected quickly through the nozzle. This non-mechanical contact driving method not only improves the response speed of the injection, but also reduces mechanical wear and prolongs the service life of the spraying device. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a cross-sectional view of the injection device provided by the present invention;

[0034] Figure 2 is a flow chart of a method for manufacturing a nozzle provided by the present invention;

[0035] Figure 3is a schematic diagram of step S1 of the method for manufacturing a nozzle provided by the present invention;

[0036] Figure 4 is a schematic diagram of step S2 of the method for manufacturing a nozzle provided by the present invention;

[0037] Figure 5 It is a schematic diagram of step S3 of the method for manufacturing a nozzle provided by the present invention.

[0038] In the figure:

[0039] 1. Capillary glass tube; 2. Heating wire; 3. Preset cutting line; 4. Nozzle; 5. Liquid storage tube; 6. Piezoelectric ceramic tube; 7. Inner electrode; 8. Outer electrode; 9. Liquid path connector. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0041] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0043] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0044] In the prior art, nozzles are usually formed by heating and then stretching a capillary glass tube. Although the diameter requirement of the nozzle can be met, the nozzle taper obtained by this manufacturing method is very small, and the fluid viscosity resistance at a micro scale is large, resulting in difficulty in ejecting microdroplets; and the nozzle obtained by stretching has low mechanical strength and is easily damaged.

[0045] To solve the above problems, Figure 2-Figure 5 As shown, this embodiment provides a method for manufacturing a nozzle. Figure 2 A schematic flow chart of a method for manufacturing a nozzle provided in this embodiment, the manufacturing method comprising:

[0046] S1, providing a capillary glass tube 1, hanging the capillary glass tube 1 vertically, and setting an electric heating wire 2 on the outer periphery of the lower end thereof;

[0047] S2, the electric heating wire 2 is heated to soften the capillary glass tube 1, and the lower end of the capillary glass tube 1 is gathered into a spherical or water drop shape, and the lower end of the capillary glass tube 1 is continuously observed;

[0048] S3, when the lower end of the capillary glass tube 1 forms a cone angle of a preset angle, the heating is stopped, and after the capillary glass tube 1 is cooled, the capillary glass tube 1 is cut according to the preset cutting line 3;

[0049] S4. Polishing the cut section.

[0050] In the method for manufacturing the nozzle provided in this embodiment, the capillary glass tube 1 is suspended vertically, and a heating wire 2 is arranged at the periphery of the lower end thereof. By controlling the temperature of the heating wire 2, the capillary glass tube 1 surrounded by the heating wire 2 can be heated and softened. Since the capillary glass tube 1 is in a suspended state, the softened part will gather into a shape as shown below under the action of surface tension and gravity. Figure 4 The spherical or teardrop-shaped shape shown can easily form a cone angle of a preset angle, and then the heating is stopped and cooled, and the capillary glass tube 1 is cut according to the preset cutting line 3 to obtain the required diameter of the nozzle 4, that is, the preset cutting line 3 is set according to the required diameter of the nozzle 4, and polishing the cut section can make the section smoother and rounder.

[0051] The nozzle 4 obtained by the manufacturing method provided in this embodiment is in the shape of an inner cone. Compared with the nozzle 4 formed by conventional stretching, the present manufacturing method significantly increases the wall thickness of the nozzle 4, making it more sturdy and durable and less prone to damage. This manufacturing method can easily make the taper of the nozzle 4 reach a preset angle, effectively reducing the viscous resistance of the fluid at a microscale, and increasing the speed of the fluid when leaving the nozzle 4, thereby significantly improving the injection efficiency and performance of the nozzle 4. The polished nozzle 4 has a smooth and rounded cross-section, further ensuring the smoothness of the fluid flow.

[0052] Specifically, Figure 2 As shown, the method for making the nozzle also includes:

[0053] S5. Coating a polytetrafluoroethylene coating on the inner surface of the capillary glass tube 1.

[0054] The friction coefficient of polytetrafluoroethylene is extremely low, which greatly reduces the resistance encountered by the fluid when flowing in the capillary glass tube 1, helping to improve the fluid delivery efficiency; polytetrafluoroethylene has excellent acid and alkali resistance, which enables the nozzle 4 to maintain stable performance when spraying corrosive fluids, thereby extending the service life of the nozzle 4.

[0055] Specifically, in the above step S2, an observation device is used to observe the lower end of the capillary glass tube 1. Through the observation device, the changes in the lower end of the capillary glass tube 1 during the heating process can be observed in real time. When the glass tube softens and begins to converge into a sphere or a drop shape under the action of surface tension and gravity, the observation device can provide accurate visual feedback. Specifically, the observation device can be a magnifying glass or a microscope, which is not limited in this embodiment.

[0056] Specifically, in the above step S3, the preset angle is 65°-90°. The cone angle of 65°-90° can reduce the viscous resistance of the fluid in the nozzle 4 to a certain extent, so that the fluid can flow out more smoothly and improve the injection efficiency; the cone angle of 65°-90° helps to stabilize the fluid flow in the nozzle 4, reduce the generation of turbulence and vortexes, thereby improving the stability and accuracy of the injection; the cone angle of 65°-90° helps to make the ejected fluid have better directionality and reduce scattering and deviation during the injection process. It should be noted that the specific size of the cone angle depends on the actual injection needs, as long as it is within the range of 65°-90°. The specific value is not limited in this embodiment. For example, the cone angle can be 65°, 70°, 75°, 80°, 85°, 90°.

[0057] Specifically, in the above step S3, after cutting according to the preset cutting line 3, the opening diameter of the capillary glass tube 1 is 10μm-200μm, that is, the diameter of the manufactured nozzle 4 is 10μm-200μm, which can be used to spray picoliter-level droplets. It should be noted that the specific size of the diameter depends on the actual spraying needs, as long as it is within the range of 10μm-200μm, and its specific value is not limited in this embodiment. For example, the diameter can be 10μm, 30μm, 100μm, 130μm, 160μm, 200μm.

[0058] Specifically, the above step S4 specifically includes:

[0059] S401, grinding the cross section;

[0060] S402, flame polishing the cross section.

[0061] Grinding can remove burrs, uneven parts and tiny cracks generated during the cutting process, making the surface of the nozzle 4 section more flat and smooth. Flame polishing uses a high-temperature flame to quickly soften and flow the glass surface, thereby filling tiny surface defects and uneven parts, making the surface achieve a higher degree of finish and smoothness, which helps to reduce the resistance of the fluid in the nozzle 4 and improve the injection efficiency. Flame polishing can eliminate the stress concentration phenomenon caused by cutting at the section, and reduce the risk of the nozzle 4 breaking due to stress concentration during use.

[0062] This embodiment also provides a nozzle 4, which is made by the above-mentioned nozzle manufacturing method. The wall thickness of this nozzle 4 is relatively thick, strong and durable, and not easy to be damaged; this nozzle 4 effectively reduces the viscous resistance of the fluid at a microscopic scale, and increases the speed of the fluid when leaving the nozzle 4, thereby significantly improving the injection efficiency and performance of the nozzle 4; this nozzle 4 can be used to spray picoliter-level tiny droplets.

[0063] like Figure 1As shown, this embodiment also provides a spraying device, which includes a liquid storage tube 5, a nozzle 4 made by the above-mentioned nozzle manufacturing method, and a piezoelectric ceramic tube 6. The liquid storage tube 5 is filled with fluid for spraying. The nozzle 4 is arranged at one end of the liquid storage tube 5 and is connected to the liquid storage tube 5. The piezoelectric ceramic tube 6 is sleeved outside the liquid storage tube 5. The inner wall surface of the piezoelectric ceramic tube 6 is connected to the inner electrode 7, and the outer wall surface of the piezoelectric ceramic tube 6 is connected to the outer electrode 8. When working, a pulse voltage is applied between the inner electrode 7 and the outer electrode 8, and the piezoelectric ceramic tube 6 expands back under the action of the pulse voltage to squeeze the liquid storage tube 5, so that the fluid in the liquid storage tube 5 is ejected from the nozzle 4. By utilizing the rapid expansion characteristics of the piezoelectric ceramic tube 6 under the action of the pulse voltage, the liquid storage tube 5 can be squeezed accurately and efficiently, thereby driving the fluid in the liquid storage tube 5 to be quickly ejected through the nozzle 4. This non-mechanical contact driving method not only improves the response speed of the injection, but also reduces mechanical wear and prolongs the service life of the equipment.

[0064] In this embodiment, if Figure 1 As shown, the nozzle 4 and the liquid storage tube 5 are integrally formed, that is, when the nozzle 4 is manufactured using the aforementioned manufacturing method, a sufficiently long capillary glass tube 1 is provided, and the portion of the capillary glass tube 1 other than the nozzle 4 is heated and formed to be used as the liquid storage tube 5. The number of connecting parts between the nozzle 4 and the liquid storage tube 5 is reduced, making the structure of the entire injection device more compact; the assembly process is simplified, reducing the production cost and assembly time; the integrally formed design avoids the interface leakage problem between the nozzle 4 and the liquid storage tube 5, and improves the sealing performance of the injection device.

[0065] Specifically, Figure 1 As shown, the piezoelectric ceramic tube 6 is located in the middle of the liquid storage tube 5. The piezoelectric ceramic tube 6 will expand or contract under the action of the pulse voltage, that is, it will vibrate at a high frequency, and the vibration waves generated will propagate to both sides along the liquid storage tube 5, and will be reflected after encountering the wall surface. The reflected vibration waves will be superimposed again into a new waveform after meeting in the middle position of the liquid storage tube 5, and the vibration waves will oscillate back and forth in the liquid storage tube 5. Placing the piezoelectric ceramic tube 6 in the middle of the liquid storage tube 5 is conducive to controlling the generation of vibration waves and suppressing residual oscillations, thereby extending the service life of the injection device.

[0066] Specifically, Figure 1 As shown, the spray device further includes a liquid circuit connector 9, which is disposed at the other end of the liquid storage tube 5 and communicates with the liquid storage tube 5. The liquid replenishing tube is connected to the liquid storage through the liquid circuit connector 9 to replenish the liquid into the liquid storage tube 5. Through the liquid circuit connector 9, the liquid replenishing tube can be easily connected to the liquid storage tube 5, thereby realizing fast and convenient fluid replenishment.

[0067] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A method for manufacturing a nozzle, characterized in that: include: S1. Provide a capillary glass tube (1), suspend the capillary glass tube (1) vertically, and arrange an electric heating wire (2) on the outer periphery of the lower end thereof; S2, the electric heating wire (2) is heated to soften the capillary glass tube (1), and the lower end of the capillary glass tube (1) is gathered into a spherical or teardrop shape, and the lower end of the capillary glass tube (1) is continuously observed; S3, when the lower end of the capillary glass tube (1) forms a cone angle of a preset angle, the heating is stopped, and after the capillary glass tube (1) is cooled, the capillary glass tube (1) is cut along a preset cutting line (3); S4. Polishing the cut section.

2. The method for manufacturing a nozzle according to claim 1, characterized in that: In step S2, an observation device is used to observe the lower end of the capillary glass tube (1).

3. The method for manufacturing a nozzle according to claim 1, characterized in that: In step S3, the preset angle is 65°-90°.

4. The method for manufacturing a nozzle according to claim 1, characterized in that: In step S3, after cutting according to the preset cutting line (3), the opening diameter of the capillary glass tube (1) is 10 μm-200 μm.

5. The method for manufacturing a nozzle according to claim 1, characterized in that: Step S4 specifically includes: S401, grinding the cross section; S402, flame polishing the cross section.

6. The method for manufacturing a nozzle according to claim 1, characterized in that: The production method further comprises: S5. Coating a polytetrafluoroethylene coating on the inner surface of the capillary glass tube (1).

7. A nozzle, characterized in that: The nozzle (4) is manufactured by the nozzle manufacturing method according to any one of claims 1 to 6.

8. A spraying device, characterized in that: include: A liquid storage tube (5), the interior of which is filled with a fluid for injection; The nozzle (4) according to claim 7, wherein the nozzle (4) is arranged at one end of the liquid storage tube (5) and is connected to the liquid storage tube (5); The piezoelectric ceramic tube (6) is sleeved outside the liquid storage tube (5), the inner wall surface of the piezoelectric ceramic tube (6) is connected to the inner electrode (7), and the outer wall surface of the piezoelectric ceramic tube (6) is connected to the outer electrode (8).

9. The spraying device according to claim 8, characterized in that The injection device also includes: A liquid circuit connector (9) is arranged at the other end of the liquid storage tube (5) and is in communication with the liquid storage tube (5); a liquid replenishing tube is connected to the liquid storage tube (5) via the liquid circuit connector (9) to replenish the liquid storage tube (5) with the fluid.

10. The spraying device according to claim 8, characterized in that The piezoelectric ceramic tube (6) is located in the middle of the liquid storage tube (5).

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