MULTISTRAHL HOHLKEGELDÜSE

Description

[0001] The present invention relates to a nozzle body made of thermoplastic material by an injection molding process or 3D printing process.

[0002] Furthermore, the invention relates to a method for producing a nozzle body.

[0003] US 2013 / 0161417 A1 shows two swirl chambers with a cylindrical geometry, into which fluid is injected tangentially from a supply channel. The fluid rotating in the swirl chamber is discharged through an outlet channel arranged off-center to the swirl chamber. For this purpose, the outlet channel is arranged obliquely to the axis of the swirl chamber. US 2020 / 0139385 A1 shows a nozzle arrangement with multiple nozzle openings connected to a cavity segment by asymmetric, frustoconical, converging fluid channels.

[0004] US 2006 / 0103051 A1 shows a microfluidic grid and a corresponding manufacturing method. WO 2012 / 055051 A1 describes a device for spraying a pressurized liquid. Vortex channels and vortex chambers are described, wherein the vortex chambers have a conical region adjoined by an outlet nozzle. The conical region and the outlet nozzle are arranged along a longitudinal chamber axis, which is arranged obliquely relative to a device axis of the mouthpiece. EP 0 661 069 A2 shows a nozzle tip with two spray openings and a nozzle bag. The nozzle bag is fed by vortex channels. WO 2004 / 043608 A1 shows a nozzle button with multiple nozzle openings, wherein the inlet region has a channel wall, which is shown conically in the figures. US 4,074,861 A shows a structure and method for controlling a spray pattern.For this purpose, an opening element with vortex channels, a vortex chamber and an inclined floor is provided.

[0005] In the injection molding process, plastic is pressed into a mold, allowing a variety of different geometries to be produced, each subject to certain limitations. For example, hole-shaped geometries have a lower diameter limit. Furthermore, undercuts, for example, are only possible to a limited extent using the injection molding process.

[0006] 3D printing is an additive manufacturing process in which plastic is printed in three dimensions. For example, plastic is applied layer by layer to create a three-dimensional structure. The 3D printing process is subject to limitations, which restricts design freedom.

[0007] The limitations of the injection molding or 3D printing process restrict the design of the nozzle body, meaning only certain geometries can be produced. Accordingly, the characteristics of the spray mist to be produced are limited.

[0008] It is therefore an object of the present invention to propose a nozzle body which allows a great degree of freedom in the design of the spray mist to be generated.

[0009] This object is achieved by the features of claim 1 and claim 8. Advantageous embodiments emerge from the subclaims.

[0010] The nozzle body has at least two hollow cone nozzle geometries. Each hollow cone nozzle geometry has a swirl chamber and a hole, also called a nozzle bore. In the swirl chamber, a fluid to be atomized is set in rotation, with the fluid exiting the nozzle body through the nozzle bore. This creates a spray cone. The at least two spray cones can at least partially overlap depending on the arrangement of the hollow cone nozzle geometries. The at least two hollow cone nozzle geometries create multiple spray cones, so that a voluminous, full spray mist can be produced. Due to the at least two spray cones that generate the spray mist, the surface area of ​​the droplets of the spray mist is larger overall for the same application than if the same amount were applied using just a single spray cone. Furthermore, the arrangement of the hollow cone nozzle geometries can be used to adapt the spray pattern.For example, the spray pattern can be made fuller, softer, or wider. Furthermore, the use of multiple hollow cone nozzle geometries can reduce the actuation force, as the fluid flows through several hollow cone nozzle geometries.

[0011] Preferably, at least one of the hollow cone nozzle geometries is asymmetrical. For example, a nozzle bore of the asymmetric hollow cone nozzle geometry is arranged eccentrically, i.e., off-center, with respect to the swirl chamber. The term "asymmetrical" does not mean rotationally symmetrical. The asymmetrical design of at least one hollow cone nozzle geometry allows for targeted control of the spray mist characteristics.

[0012] Preferably, a nozzle bore of the asymmetric hollow cone nozzle geometry has a longitudinal axis with an angle of <90°, preferably greater than or equal to 50° and less than or equal to 88°, particularly preferably greater than or equal to 70° and less than or equal to 87°, to a nozzle exit surface. The nozzle exit surface corresponds to a surface through which fluid exits during application. Depending on the arrangement of individual hollow cone nozzle geometries, this can, for example, generate a very broad overall spray. Accordingly, the characteristics of the spray to be generated can be influenced by adjusting the angle.

[0013] Preferably, the hollow cone nozzle geometries each have a nozzle bore with a diameter of ≤ 300 µm, preferably ≤ 200 µm, particularly preferably ≤ 100 µm. Correspondingly small nozzle bores can produce a spray mist with correspondingly small droplets.

[0014] Preferably, the at least two hollow cone nozzle geometries are arranged symmetrically to one another. For example, the hollow cone nozzle geometries can be arranged point-symmetrically, rotationally symmetrically, or mirror-symmetrically to one another, so that a uniform spray mist can be generated.

[0015] The nozzle body preferably comprises a material with at least one main component from the group consisting of PMMA (polymethyl methacrylate), POM (polyoxymethylene), PP (polypropylene), PE (polyethylene), ABS (acrylonitrile-butadiene-styrene copolymer), COC (cycloolefin copolymer), PA (polyamide), PC (polycarbonate), PBT (polybutylene terephthalate), PEEK (polyetheretherketone), PEI (polyetherimide), PET (polyethylene terephthalate), and PPE (polyphenylene ether). These materials are thermoplastics and can be easily processed by injection molding or 3D printing, either alone or in combination. A combination, for example, would be a mixture of PE and PP.

[0016] Preferably, the at least two hollow cone nozzle geometries are at least partially produced by laser processing. The at least partial laser processing can, for example, use methods of laser ablation, laser drilling, or 3D laser ablation. Laser ablation refers to the removal of material from a surface by bombardment with a pulsed laser. The laser or laser radiation leads to rapid heating and consequently the formation of a plasma on the surface of the workpiece. Laser drilling is also a non-cutting machining process in which so much energy is introduced into the workpiece using laser radiation that the material is melted and partially vaporized. 3D laser ablation is a special constellation of laser ablation in which material is processed in three dimensions. Furthermore, a combination of the aforementioned methods is possible, for example.For example, at least partial laser processing allows for the creation of a single hollow cone nozzle geometry. Alternatively, the entire hollow cone nozzle geometry can be produced using laser processing. This allows for a high degree of design freedom and flexibility.

[0017] Furthermore, the object is achieved by a method having the features of claim 8.

[0018] Laser processing allows for flexible design and production of hollow cone nozzle geometries. Furthermore, laser processing enables geometries such as undercuts that cannot be produced, or can only be produced to a limited extent, using injection molding or 3D printing. This allows for the targeted control of the spray mist generated by the hollow cone nozzle geometries of the nozzle body. This control is achieved by adjusting the hollow cone nozzle geometries, which can be easily adapted using laser processing.

[0019] Laser processing preferably uses laser ablation, laser drilling, and / or 3D laser ablation methods. In laser ablation, material is removed from a surface by bombarding it with a pulsed laser beam or pulsed laser radiation. In laser drilling, the laser radiation locally introduces sufficient energy into the workpiece to melt and partially vaporize the material. Melting of the material at the edge of the hole is undesirable. A combination of the aforementioned methods is also feasible. This allows for considerable design flexibility for the hollow cone nozzle geometry or nozzle body.

[0020] Preferably, laser processing produces at least one asymmetric hollow cone nozzle geometry. The term "asymmetric" refers to an arrangement in which a nozzle bore of the hollow cone nozzle geometry is arranged off-center, i.e., eccentrically, to the swirl chamber. Accordingly, the hollow cone nozzle geometry is not rotationally symmetric. The term "asymmetric" means not rotationally symmetric. This arrangement allows a spray cone of the asymmetric hollow cone nozzle geometry to be adapted to corresponding specifications, so that, for example, a very wide overall spray mist can be generated.

[0021] Preferably, the laser processing creates a nozzle bore of the asymmetrical nozzle geometry with an axis at an angle of < 90°, preferably greater than or equal to 50° and less than or equal to 88°, particularly preferably greater than or equal to 70° and less than or equal to 87°, to an exit surface. This allows the overlap of the spray cones to be adjusted, thus influencing the characteristics of the overall spray mist.

[0022] Laser processing preferably produces a nozzle bore of each hollow cone nozzle geometry with a diameter of ≤ 300 µm, preferably ≤ 200 µm, and particularly preferably ≤ 100 µm. Laser processing is an efficient and flexible method for producing nozzle bores with these diameters. Laser processing also makes it easy to adjust the nozzle bore diameters. This allows for flexible response to new requirements.

[0023] Preferably, the at least two hollow cone nozzle geometries are generated symmetrically to each other. The symmetrical arrangement of the hollow cone nozzle geometries allows for the generation of a symmetrical spray mist. Fluid droplets are distributed accordingly evenly within the spray mist.

[0024] The injection molding process or 3D printing process preferably uses a material with at least one main component from the group PMMA (polymethyl methacrylate), POM (polyoxymethylene), PP (polypropylene), PE (polyethylene), ABS (acrylonitrile-butadiene-styrene copolymer), COC (cycloolefin copolymer), PA (polyamide), PC (polycarbonate), PBT (polybutylene terephthalate), PEEK (polyetheretherketone), PEI (polyetherimide), PET (polyethylene terephthalate), and PPE (polyphenylene ether). The injection molding process or the 3D printing process using plastic is a common process that represents a cost-effective way to produce nozzle bodies from one or more plastics. For example, the nozzle body can be made from a single material or from a combination or mixture of various materials mentioned. An example of a mixture is PE and PP.

[0025] The invention is described below using a preferred embodiment in conjunction with the drawings. In the drawings: Fig. 1 is a schematic plan view of a nozzle body of a first embodiment, Fig. 2 is a schematic sectional view of a nozzle body of the first embodiment, Fig. 3 is a schematic plan view of a nozzle body of a second embodiment, Fig. 4 is a schematic sectional view of a nozzle body of the second embodiment, Fig. 5 is a schematic sectional view of an asymmetric hollow cone nozzle geometry, Fig. 6 is a schematic sectional view of a symmetric hollow cone nozzle geometry.

[0026] Fig. 1 shows a nozzle body 1 with five asymmetric hollow cone nozzle geometries 2, each having a nozzle bore 3 and a vortex chamber 4. The asymmetric hollow cone nozzle geometries 2 are each connected to a vortex channel 5. Furthermore, Fig. 1a section plane AA is shown, which at the same time represents a plane of symmetry of the hollow cone nozzle geometry arrangement.

[0027] Identical elements are identified by the same reference numerals regardless of the embodiment.

[0028] Fig. 2 shows a sectional view of the Fig. 1 illustrated nozzle body 1 along the section plane AA. The asymmetric hollow cone nozzle geometry 2 shown is arranged essentially obliquely to a nozzle outlet surface 6. Fig. 3 shows a second embodiment of the nozzle body 1 with asymmetric hollow cone nozzle geometries 2 and symmetric hollow cone nozzle geometries 7. The arrangement of the hollow cone nozzle geometries 2, 7 is symmetrical to the section plane or symmetry plane AA. Each of the hollow cone nozzle geometries 2, 7 has a vortex chamber 4 and a nozzle bore 3. Furthermore, each of the hollow cone nozzle geometries 2, 7 is connected to a vortex channel 5.

[0029] Fig. 4 shows the second embodiment of the nozzle body 1 along the section plane AA. A longitudinal axis 8 of the nozzle bore 3 of the asymmetric hollow cone nozzle geometry 2 forms an angle α to a perpendicular to the nozzle outlet surface 6. The longitudinal axis 8 of the symmetric hollow cone nozzle geometry 7 is arranged parallel to the perpendicular to the outlet surface 6.

[0030] Fig. 5 shows a detailed view of the asymmetric hollow cone nozzle geometry 2. The longitudinal axis 8 of the nozzle bore 3 has an angle of < 90° relative to the nozzle exit surface 6. The asymmetric hollow cone nozzle geometry 2 includes not only the nozzle bore 3 but also the swirl chamber 5. According to the invention, the swirl chamber 5 has an asymmetric cone geometry.

[0031] In this description, asymmetric does not mean rotationally symmetric. However, other symmetries, such as mirror symmetry, are possible.

[0032] Fig. 6 shows a detailed view of the symmetrical hollow cone nozzle geometry 7. This has a swirl chamber 5 and a nozzle bore 3, wherein the nozzle bore 3 has a longitudinal axis which is arranged perpendicular to the outlet surface 6.

[0033] The nozzle body 1 comprises, as a main component, thermoplastic material, preferably PMMA (polymethyl methacrylate), POM (polyoxymethylene), PP (polypropylene), PE (polyethylene), ABS (acrylonitrile-butadiene-styrene copolymer), COC (cycloolefin copolymer), PA (polyamide), PC (polycarbonate), PBT (polybutylene terephthalate), PEEK (polyetheretherketone), PEI (polyetherimide), PET (polyethylene terephthalate) and / or PPE (polyphenylene ether). The plastic is processed into the nozzle body 1 by means of an injection molding process or a 3D printing process, wherein the hollow cone nozzle geometries 2, 7 are subsequently produced by laser processing. For example, methods of laser ablation, laser drilling and / or 3D laser ablation can be used.

[0034] Laser processing allows for the production of nozzle bores 3 with diameters of ≤ 300 µm, preferably ≤ 200 µm, and particularly preferably ≤ 100 µm. These dimensions refer to the smallest diameter of the nozzle bore 3.

[0035] The longitudinal axis 8 of the asymmetric hollow cone nozzle geometry 2 has an angle of < 90° to the outlet surface 6. A preferred angle is 85°. Accordingly, the longitudinal axis 8 of the asymmetric hollow cone nozzle geometry 2 is inclined by the angle α to a perpendicular to the outlet surface 6. This is shown in Fig. 4 In the present exemplary embodiment, the angle α is 5°, so that the longitudinal axis 8 of the asymmetric hollow cone nozzle geometry 2 has an angle of 85° to the nozzle exit surface 6. Alternative angles are, for example, in the range greater than or equal to 50° and less than or equal to 88°, or alternatively, for example, in the range greater than or equal to 70° and less than or equal to 87° with respect to the exit surface 6. List of reference symbols

[0036] 1Nozzle body 2Asymmetric hollow cone nozzle geometry 3Nozzle bore 4Swirl chamber 5Swirl channel 6Nozzle exit surface 7Symmetric hollow cone nozzle geometry 8Longitudinal axis of the nozzle bore

Claims

1. Nozzle body (1) which is produced from a thermoplastic material by an injection moulding process or 3D printing process, the nozzle body (1) having at least two hollow cone nozzle geometries (2, 7) each with a nozzle bore (3) and a swirl chamber (4), characterized in that the swirl chamber (4) has an asymmetrical cone geometry and is connected to a swirl channel (5).

2. Nozzle body (1) according to claim 1, characterized in that at least one of the hollow cone nozzle geometries (2) is asymmetrical.

3. Nozzle body (1) according to claim 2, characterized in that a nozzle bore of the asymmetrical hollow cone nozzle geometries (2) has a longitudinal axis (8) with an angle of less than 90°, preferably greater than or equal to 50° and less than or equal to 88°, particularly preferably greater than or equal to 70° and less than or equal to 87°, to a nozzle outlet surface (6).

4. Nozzle body (1) according to one of claims 1 to 3, characterized in that the hollow cone nozzle geometries (2, 7) each have a nozzle bore (3) which has a diameter less than or equal to 300 µm, preferably less than or equal to 200 µm, particularly preferably less than or equal to 100 µm.

5. Nozzle body (1) according to one of claims 1 to 4, characterized in that the at least two hollow cone nozzle geometries (2, 7) are arranged symmetrically to one another.

6. Nozzle body (1) according to one of claims 1 to 5, characterized in that the nozzle body (1) has a material with at least one main component from the group PMMA, POM, PP, PE, ABS, COC, PA, PC, PBT, PEEK, PEI, PET and PPE.

7. Nozzle body (1) according to one of claims 1 to 6, characterized in that the at least two hollow cone nozzle geometries (2, 7) are at least partially produced by laser machining.

8. Method for producing a nozzle body (1) from a thermoplastic material according to one of claims 1 to 7, characterized in that the method comprises the following step: a) Producing the nozzle body (1) by an injection molding process or 3D printing process; b) At least partial production of at least two hollow cone nozzle geometries (2, 7) each with a nozzle bore (3) and a swirl chamber (4) by laser machining, wherein the swirl chamber (4) has an asymmetrical cone geometry and is connected to a swirl channel (5).

9. Method according to claim 8, characterized in that the laser processing uses methods of laser ablation, laser drilling and / or 3D laser ablation.

10. Method according to claim 8 or 9, characterized in that the laser processing produces at least one asymmetrical hollow cone nozzle geometry (2).

11. Method according to one of claims 8 to 10, characterized in that the laser processing produces a nozzle bore (3) of the asymmetrical hollow cone nozzle geometry (2) having a longitudinal axis (8) with an angle of less than 90°, preferably greater than or equal to 50° and less than or equal to 88°, particularly preferably greater than or equal to 70° and less than or equal to 87°, to an exit surface (6).

12. Process according to one of claims 8 to 11, characterized in that the laser processing produces a respective nozzle bore of the hollow cone nozzle geometries (2, 7) with a diameter less than or equal to 300 µm, preferably less than or equal to 200 µm, particularly preferably less than or equal to 100 µm.

13. Process according to one of claims 8 to 12, characterized in that the at least two hollow cone nozzle geometries (2, 7) are produced symmetrically to each other.

14. Process according to one of claims 8 to 13, characterized in that the injection moulding process uses a material with at least one main component from the group PMMA, POM, PP, PE, ABS, COC, PA, PC, PBT, PEEK, PEI, PET and PPE.