Method for processing part for aerosol supply system

Abstract

A method of processing a part for an aerosol supply system, the method comprising: making a mold for the part from metal, the making comprising defining an oppositely textured surface on at least a portion of the mold using one or more laser beams, the oppositely textured surface having a surface shape opposite a desired textured surface of the part, the surface shape comprises a plurality of textural features, and the size of one or more sizes of the plurality of textural features ranges from 1 m to 10 m; injecting a liquid plastic material of a part to be formed into the mold; hardening the liquid plastic material; and releasing the hardened plastic material from the mold to obtain a part having a textured surface.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a machining method for machining a part for an aerosol provision system, a machining method for machining a machining part for machining a part for an aerosol provision system, and a machining part for machining a part for an aerosol provision system. BACKGROUND

[0002] Aerosol provision systems, such as electronic cigarettes and other electronic nicotine delivery systems that deliver nicotine via vaporisation of a liquid, comprise a reservoir or other liquid storage portion for holding a liquid aerosolisable substrate material. Such systems are designed to deliver liquid from the reservoir to an atomiser that generates a vapour from the liquid that is entrained in air flowing through the system on inhalation by a user to form an aerosol for inhalation. Liquid delivery is typically achieved by a porous wick that absorbs liquid from the reservoir and transports the liquid by capillary action to the atomiser, which can be an electrically heated element. Liquid can leak from the reservoir without being vaporised by the atomiser, such as via an outlet extending through the porous wick of the reservoir, or by dripping from a saturated wick, or vaporised liquid can re-condense from the inhalable aerosol. This can create free liquid within the aerosol provision system. Another source of free liquid is condensation of water vapour from air drawn through the aerosol provision system on inhalation by a user on the aerosol provision system to obtain an aerosol. This latter situation can also occur in a heated tobacco aerosol provision system in which a portion of tobacco is heated to release nicotine and other constituents to be entrained in a flow of air to provide an inhalable aerosol. Liquid from these or other events can be able to move within the aerosol provision system and flow to a location where its presence can have an adverse effect. This excess liquid can leak from the system to soil the user and the user's possessions, or can undesirably interact with components within the system to cause corrosion and malfunction, such as electrical shorting or poor performance.

[0003] Textured surfaces on faces within aerosol provision systems have been proposed as a technique to address excess free liquid. A suitably configured textured surface can interact with surface tension in a small volume of liquid to inhibit or interrupt movement of the liquid on the face, so that the liquid can be kept away from locations where it can cause problems.

[0004] Accordingly, techniques for forming textured surfaces on parts of liquid aerosol provision systems are of interest. SUMMARY

[0005] According to a first aspect of some embodiments described herein, a method for processing a part for an aerosol supply system is provided, the method comprising: fabricating a mold for the part from metal; the fabrication comprising defining an opposite textured surface on at least a portion of the mold using one or more laser beams, the surface shape of the opposite textured surface being opposite to the desired textured surface of the part, and the surface shape comprising a plurality of textured features, one or more of the plurality of textured features being in the range of 1 µm to 10 µm; injecting a liquid plastic material of the part to be formed into the mold; hardening the liquid plastic material; and releasing the hardened plastic material from the mold to obtain a part having a textured surface.

[0006] According to a second aspect of some embodiments described herein, a method for processing parts for an aerosol supply system is provided, the method comprising: injecting a liquid plastic material of the part to be formed into a mold, wherein the mold is formed of metal and includes an opposite textured surface on at least a portion of the mold, the surface shape of the opposite textured surface being opposite to the textured surface required for the part, and the surface shape including a plurality of textured features created by etching the metal using one or more laser beams, the size of one or more of the plurality of textured features being in the range of 1 µm to 10 µm; hardening the liquid plastic material; and releasing the hardened plastic material from the mold to obtain a part having a textured surface.

[0007] According to a third aspect of some embodiments described herein, a method for machining a component is provided, the method comprising: fabricating a machined component from metal for machining a part for an aerosol supply system, the fabrication comprising defining an opposite textured surface on at least a portion of the machined component using one or more laser beams, the surface shape of the opposite textured surface being opposite to the textured surface required for the part for the aerosol supply system, and the surface shape comprising a plurality of textured features, one or more of the plurality of textured features having a size in the range of 1 µm to 10 µm.

[0008] According to a fourth aspect of some embodiments described herein, a machined part for processing a component for an aerosol supply system is provided, the machined part being formed of metal, and the machined part including, at least a portion thereof, an opposite textured surface, the surface shape of which is opposite to the textured surface required for the component for the aerosol supply system, and the surface shape including a plurality of laser-etched textured features, one or more of which are in the range of 1 µm to 10 µm.

[0009] According to a fifth aspect of some embodiments described herein, a method for processing a part for an aerosol supply system is provided, the method comprising: etching a textured surface directly onto a portion or all of the surface of the part of the aerosol supply system using one or more laser beams, the textured surface comprising a plurality of texture features, one or more of the texture features being in the range of 1 µm to 10 µm.

[0010] These and other aspects of certain embodiments are set forth in the appended independent and dependent claims. It should be understood that features of the dependent claims can be combined with each other and with features of the independent claims, and are not limited to those combinations expressly set forth in the claims. Furthermore, the methods described herein are not limited to specific embodiments such as those set forth below, but include and contemplate any suitable combination of features presented herein. For example, according to the methods described herein, a method or a machined component may be provided that, as appropriate, includes any one or more of the various features described below. Attached Figure Description

[0011] Embodiments of the present invention will now be described in detail by way of example only, with reference to the following accompanying drawings, in which: Figures 1A-1E A highly schematic and non-scale plan view showing a portion of different instances of a textured surface; Figure 2 and Figure 3 A highly schematic and non-scaled cross-sectional view is shown through a portion of two exemplary textured surfaces; Figure 4 and Figure 5 Photographic images of portions of two exemplary textured surfaces are shown; Figures 6A-6F A simplified schematic graphical representation of the steps in an exemplary method for processing parts for an aerosol supply system according to the present disclosure is shown; and Figure 7 A flowchart is shown of steps in an exemplary method for processing parts for an aerosol supply system according to the present disclosure. Detailed Implementation

[0012] This document discusses / describes aspects and features of certain instances and implementations. Some aspects and features of certain instances and implementations can be conventionally implemented, and for the sake of brevity, these aspects and features are not discussed / described in detail. Therefore, it will be understood that the aspects and features of the devices discussed herein that are not described in detail can be implemented according to any conventional techniques used to implement such aspects and features.

[0013] It has been determined that textured surfaces, including multiple textured features on the order of micrometers, can control the movement, passage, or flow of liquid on surfaces with textured surfaces. In the case of aerosol supply systems, such textured surfaces on the surfaces of components within the assembled aerosol supply system can be used to manipulate excess free liquid that may be present with the system due to internal leaks or condensation by keeping the liquid away from locations that could cause damage, malfunction, poor performance, and / or external leaks.

[0014] The textured surface considered in this paper includes multiple micrometer-sized texture features. These features are distributed on a two-dimensional region or portion of the surface on which the textured surface is disposed. Within this region, the texture features include multiple protrusions / recesses, pits / boobs, peaks / valleys, etc., scattered throughout the region. Relative to the planar height of the surface surrounding the region, the texture features may include protrusions / boobs / peaks above the planar height of the surface (such that the space between these features is at the planar height), or may include recesses / pits / valleys below the planar height of the surface (such that the space between these features is at the planar height), or may include both (such that the planar height of the surface is between the height of the protrusions / boobs / peaks and the depth of the recesses / pits / valleys).

[0015] Different configurations of texture features can inhibit the flow or movement of liquids on textured surfaces in different ways, due to the different interactions between the liquid surface tension and the different shapes, sizes, configurations, etc., of the features. Some examples will now be described, but this disclosure is not limited to this approach, and textured surfaces with different configurations can also be fabricated using the techniques presented herein. In two specific examples, several different texture features can form a textured surface configured to inhibit the passage of liquids by adhering the liquid incident on the surface to the textured surface, or by allowing the liquid incident on the surface to flow or move in one direction while restricting or prohibiting its movement in substantially orthogonal directions.

[0016] Figure 1AA highly schematic and non-scale plan view representation of a first example of a textured surface configured for liquid adhesion is shown. To enable liquid adhesion, the textured surface has a plurality of discrete textured features 100 on a face 101 on which the textured surface is disposed. The textured features 100 are arranged to be spaced apart from each other in two dimensions of the plane of face 101 over the area occupied by the textured surface. In this example, the textured features 100 are arranged in a regular or periodic array of triangles. Because the textured features 100 are discrete and separated from each other, each feature may include a protrusion or peak extending from the plane of face 101, or may include a recess or pit “cut out” below the plane of face 100, or may include a combination of both. The textured features 100 are depicted as having a generally circular cross-section parallel to the plane of face 101, but this is not required, and these features may have any cross-sectional shape.

[0017] Figure 1B A highly schematic, non-scale plan view representation of a second instance of a textured surface configured for adhering liquids is shown. This is similar to... Figure 1A This is an example, but in this case, texture features 100 are arranged in a square array at regular intervals. Other periodic distributions conforming to other regular arrays can also be used if desired. Alternatively, irregular or non-periodic distributions can be used.

[0018] Figure 1C A highly schematic, non-scale plan view of a third example of a textured surface configured for liquid adhesion is shown. In this example, textured features 100 are randomly distributed on surface 101 at irregular and non-constant intervals, without any intended periodicity. Comparing the first and third examples, it can be found that a regular arrangement with constant intervals is best suited for achieving adhesion of liquids with a specified viscosity, allowing the intervals and regularity to be selected accordingly for specific liquids, such as water or selected types of aerosolizable matrix materials. Conversely, a non-periodic arrangement with a certain range of intervals between textured features can be used to adhere liquids with viscosities within a certain range, allowing a single textured surface to manipulate different liquids.

[0019] Figure 1DA highly schematic and non-scale plan view of a first example of a portion of a textured surface configured to guide or control the direction of movement of a liquid flow incident on the textured surface is shown. To manipulate the direction of liquid movement in this way, the textured surface may take the form of a plurality of continuous textured features 100 on a face 101 on which the textured surface is disposed. Textured features 100 include a plurality of substantially parallel ridges 102 extending from the plane of face 101, and / or may include grooves / valleys / channels “carved out” below the plane of face 100, or a combination of both. In this example, the ridges / grooves are substantially straight. Therefore, the textured features 102 are continuous in one direction (the ridges / grooves along their length direction) and spaced apart from each other in orthogonal directions (at substantially constant intervals). The effect of this configuration of the textured features 102 is to interrupt or impede any movement of incident liquid in the orthogonal direction indicated by arrow X, while allowing or facilitating any movement of incident liquid in the length direction indicated by arrow Y. In the context of using the textured surface disclosed herein, the orthogonal direction can be considered a "lateral" direction, and it is desirable to inhibit the flow of liquid along this "lateral" direction, such that the textured surface inhibits the liquid from reaching the distal side of the textured surface. Therefore, positions on the distal side of the textured surface can be protected from exposure to any liquid passing over the surface on which the textured surface is disposed. Conversely, movement of the incident liquid along the length direction of the ridge / groove is facilitated, thereby deviating it from the lateral direction, or intentionally promoting its movement along the length direction, or both.

[0020] Figure 1E A highly schematic, non-scale plan view representation of a second example of a textured surface configured to control the direction of liquid movement is shown. Texture feature 102 also includes a plurality of substantially parallel ridges / grooves, but in this example, the ridges / grooves are formed in annular shapes and arranged substantially concentrically. The depicted example shows the annular shape as a circle, but this is not mandatory, and other shapes can be used in configurations where the grooves / ridges are not defined as straight lines over the extent of the textured surface. The concentric arrangement defines the lateral direction X of the textured surface as the direction between the center and the outer edge of the area covered by the textured surface. In this way, liquid movement can be inhibited from points near the center of the textured surface outwards, or from points outside the textured surface inwards towards the center. The direction Y along which the textured surface allows liquid movement is the circumferential direction.

[0021] Figure 2A highly schematic, non-scale cross-sectional view through an exemplary textured surface is shown to indicate some relevant parameters. In this example, the textured features include pits or grooves formed in the face on which the textured surface is disposed. Three textured features are shown, but in reality, there may be more features along the line through the textured surface. The first relevant parameter is the spacing s, which is shown as the center-to-center distance or gap between adjacent textured features. By way of example only, the spacing s can be about 20 µm or about 25 µm. More generally, the spacing can range from 15 µm to 30 µm, however, larger and smaller spacings are not excluded, for example, in the range of 10 µm to 50 µm. Within the textured surface or within a portion of the textured surface, the spacing can be constant (within manufacturing tolerances, and for example, within 2 µm or 5 µm), or various values ​​that vary in the range up to about 10 µm can be selected, for example, to better manipulate liquids with different viscosities. The second relevant parameter is one or more dimensions of the size of the individual textured feature, which in Figure 2 The width w is indicated in the direction of the plane parallel to the textured surface and the surface on which the textured surface is disposed, but more generally, it includes the height of the protruding feature and the depth of the recessed or concave feature. These sizes within an individual feature may or may not be substantially the same, such that the width may be approximately the same as the height / depth, or the width may be less than or greater than the height / depth, but generally within the same order of magnitude. For example, these individual sizes may have dimensions of about 2 µm or about 3 µm, however, larger or smaller sizes are not excluded, and may be, for example, at least 1 µm, or up to 5 µm, or up to 10 µm. For example, in some cases, the size of one or more dimensions of the textured feature may be in the range of 2 µm to 5 µm, or 1 µm to 10 µm. Within the textured surface or within a region of the textured surface, the size of all textured features may be constant (within manufacturing tolerances, and may be, for example, within 0.5 µm or 1 µm), or various values ​​may be selected that vary within a range, for example, to better manipulate liquids with different viscosities.

[0022] Since the size of individual features and the spacing between adjacent features can be selected, another parameter that may be relevant when characterizing textured surfaces is the density of texture features within the textured surface. Density can be defined as the number of texture features per unit area, or as the number of texture features per unit length on the textured surface, to more effectively encompass both discrete texture features and parallel grooves / ridges. For example, the density can be chosen to be approximately 3, 4, or 5 features per 100 µm (and therefore per 100 µm). 2The density can be approximately 9, 16, or 25 features, but higher or lower values ​​can be used as needed, for example, in the range of approximately 2 to 10 features per µm. Furthermore, the density can be approximately constant across the textured surface, or it can be selected to vary to provide a textured surface more capable of handling liquids with a range of viscosities.

[0023] Texture features can be customized to adapt the liquid manipulation properties of the textured surface to liquids of varying viscosities, as different viscosities result in varying surface tensions in small volumes of liquid. As mentioned above, the relevant liquids within an aerosol supply system are water condensed from the air flowing within the system, and liquid aerosolizable matrix materials that may leak from reservoirs or other liquid storage sections, drip from saturated cores, or condense from previously evaporated aerosolizable matrix materials used to form aerosols. Liquid aerosolizable matrix materials typically have a higher viscosity than water, and the dimensions of the texture features can be configured to handle any of these liquid types considered representative of the main problems within an aerosol supply system, or texture features for two liquid types can be located in different textured surfaces or at different locations within a textured surface, or combined within a single textured surface. If it is envisioned that a user might use different aerosolizable matrix materials in a single aerosol supply system, the dimensions of the texture features can also be designed to accommodate different viscosities of the aerosolizable matrix materials within a certain range. As mentioned above, a suitable exemplary range for the dimensions of the texture features constituting the textured surface is typically 1 µm to 10 µm.

[0024] Figure 3 A highly schematic and non-scaled cross-sectional view through another exemplary textured surface is shown, wherein individual texture features have the form of protrusions or ridges extending outward from the face bearing the textured surface.

[0025] Figure 4 A photographic image of a portion of a non-limiting example of a textured surface is shown, comprising multiple discrete texture features in the form of spaced-apart pits. A 100 µm scale bar is indicated.

[0026] Figure 5 A photographic image of a portion of a non-limiting example of a textured surface is shown, comprising multiple textured features in the form of spaced-apart parallel grooves. A 100 µm scale bar is indicated.

[0027] Textured surfaces (such as those described above) can be applied to the surfaces of aerosol supply system parts in a variety of ways, such as after the parts have been fabricated. Textured surfaces can be conveniently achieved before the parts are assembled into the overall aerosol supply system, at which point the surfaces of the parts are easily accessible. For example, liquid particle formulations can be applied to relevant areas of the surface by spraying, printing, or smearing, allowing for drying. Alternatively, textured features can be formed by machining the surface to remove portions of the material used to fabricate the parts. These techniques (such as those requiring specialized machining of individual parts for many aerosol supply systems) add extra processing steps and thus increase costs and manufacturing time, which is undesirable for very large products such as aerosol supply systems. There are also issues related to repeatability; these techniques can produce inconsistent results between parts, resulting in variability between individual aerosol supply systems. Furthermore, coatings capable of providing a suitable texture may not be safe for use in aerosol supply systems and may interact with liquid aerosolizable matrix materials.

[0028] A way to avoid these problems is to utilize molding to form the textured surface while manufacturing the part on which the textured surface is to be provided. If the mold includes an opposite textured surface in the area where the textured surface is required on the face of the aerosol supply system part, the part (if it is itself molded) can be made to have a textured surface as an inherent feature, wherein the surface shape of the opposite textured surface is opposite to the desired surface shape of the desired textured surface. One or more dimensions of the textured features of the opposite textured surface match one or more dimensions of the required textured features of the textured surface to be provided on the aerosol supply system part, because they are opposite to each other. Thus, the opposite textured surface includes textured features with one or more dimensions ranging from 1 µm to 10 µm, as described above regarding the textured surface itself.

[0029] In this way, the parts and their textured surfaces are processed together in a single manufacturing step, saving time and cost. Using a mold to define the textured features of the textured surface also provides consistency; each part made in the same mold will have the same textured surface pattern defined on it.

[0030] However, it is important to note that textured surfaces include texture features with micrometer-sized dimensions (height / depth, width, spacing). Such small features are difficult to accurately form through molding.

[0031] Therefore, this disclosure proposes a molding process for parts used in aerosol supply systems, wherein the mold is made of metal, and the desired opposite textured surface is defined on the relevant portion of the mold (i.e., the portion of the mold corresponding to the face of the aerosol supply system part that requires the textured surface) by etching or engraving with one or more laser beams. Using metal as the mold material allows laser processing to be applied to the mold without damaging it due to melting or other heat exposure issues, and the use of a laser beam (which can be focused to a very small spot size) allows for the realization of the micrometer-level details required for the opposite textured surface. The textured features are etched into the metal, i.e., formed by laser ablation of the metal material of the mold. Ablation is a process of removing material from a larger volume of material (the substrate, in this case, the metal block of the mold), wherein a high-intensity focused laser beam irradiates the larger volume of material, delivering a high-level flux (typically a short pulse), transferring its energy to the irradiated material, which is then converted into plasma and carried away from the substrate. Furthermore, to accurately reproduce the minute details of the surface shape defined on the mold, the aerosol supply system parts are machined using injection molding with the mold. Under appropriate pressure, liquid plastic material suitable for the type of part is injected into the mold to force the liquid plastic material fully into the cavities and recesses of the opposite textured surface, ensuring that the textured surface on the molded part properly (in reverse) includes all the features of the opposite textured surface.

[0032] Figures 6A-6F The steps in an exemplary method for fabricating parts for an aerosol supply system according to the proposed technique are illustrated graphically. These figures are highly simplified and schematic, non-scale cross-sectional representations.

[0033] Figure 6A A first mold portion 10, made of metal, is shown. This first mold portion will be assembled with one or more other mold portions to create a complete mold. Mold portion 10 includes a base and sidewalls that together define a recess 10b, which will be all or part of the internal cavity or space of the complete mold. The inner surface 10a of mold portion 10 is provided by the upper surface (as drawn) of the base of mold portion 10a, and provides a surface defining an oppositely textured surface thereon. Note that for illustrative purposes, a very simple rectangular recess 10b is shown; in reality, the cavity may have a more complex and delicate shape, the opposite of the desired external shape of the aerosol supply system part to be machined in the complete mold.

[0034] Figure 6BA simplified exemplary apparatus for defining an opposite textured surface on the inner surface 10a of a mold portion 10 is shown. A light source 12 in the form of a laser is provided, which emits a laser beam 14. The beam 14 passes through a focusing arrangement to form a focused laser beam 18 guided onto the inner surface 10a, the focusing arrangement including one or more lenses and / or mirrors or other beam shaping and guiding optics 16. An etching or ablation process is performed, during which the focused beam 18 is guided to different locations on the inner surface 10a to remove metal material from the mold portion 10 at desired locations and to a desired depth, thereby defining the desired textured features of the opposite textured surface. The desired location can be approached by inducing relative movement (indicated by double-headed arrows) between the focused beam 18 and the mold portion 10 in the plane of the inner surface 10a, such relative movement being achieved by movement of the light source 12, movement of the optics 16, or movement of the mold portion 10, or by some combination of these movements. In practice, the focused beam 18 scans over at least a desired portion of the textured surface of the inner surface 10a corresponding to the aerosol supply system component to “write” onto the opposite textured surface. Thus, the opposite textured surface covers at least a portion of the mold and, in some cases, can be defined over the entire cavity, depending on the desired extent of textured surface on the aerosol supply component. One or more of the light source 12, optical elements 16, and mold portions may be mounted on a translation platform (not shown) or otherwise provided with mobility to enable relative movement. The desired depth of removal of metallic material by etching can be achieved by altering the characteristics of the laser beam, including: the power of the focused beam 18 (changing the intensity of the focused beam at the inner surface 10a for a given spot size); and / or the duration of any light pulses emitted by the laser beam 14 from the light source 12; and / or the total exposure time of the focused beam 18 at each location. One or more widths of the textured feature can be achieved by adjusting the focal spot size of the focused beam 18 at surface 10a and / or by relative movement. Movement and beam variation can be achieved via controller 20, which is configured to generate control signals in response to programming specified to induce an appropriate ablation pattern to define a desired opposite textured surface and send them to a light source and / or any platform for moving the mold section 10, the light source, or the focusing arrangement. One or more additional laser beams can be used in parallel or in series with the depicted laser beam to increase the etching rate (so that more than one location can be ablated at a time) or to provide laser beams with different characteristics to alter the ablation process.

[0035] Figure 6CA complete mold 22 is shown, formed by a mold portion 10 having a textured surface 20 defined on its inner surface 10a and a second mold portion 11. The second mold portion 11 includes sidewalls and a top defining a recess, such that when the second mold portion 11 is properly engaged with the mold portion 10, the recesses of the two mold portions 10, 11 combine to define an internal cavity or chamber 23 of the mold 22. An opening 21 is provided in the second mold portion 11, allowing access to the inner cavity 23 for the purpose of filling the mold 22. For simplicity, two mold portions are shown; more mold portions could be used to create the complete mold 22, and additional textured surfaces could be defined on the inner surfaces of the mold portions if required for aerosol supply system components. Alternatively, the mold portion with the textured surface could take the form of an insert that mates with a larger mold portion or the entire mold, rather than a portion that actually defines part of the mold cavity.

[0036] Figure 6D The filling of mold 22 is illustrated. A reservoir or hopper 24 supplies liquid plastic material 26, from which parts of the aerosol supply system need to be made. Plastic material 26 is injected into mold 22 through opening 21 to fill cavity 23. Injection is performed at a suitable pressure P and speed (which can vary during filling) to ensure that the liquid plastic material flows in and fills all and any recesses, corners, and cracks in cavity 23, including all texture features of the opposite textured surface 20.

[0037] Figure 6E A filled mold 22 is shown. Cavity 23 is filled with liquid plastic material 26, which then hardens to form an aerosol supply system component. As those skilled in the art will understand, hardening can occur simply by the passage of time, or by performing a curing process.

[0038] Figure 6F The final step in the processing method is shown: releasing the now-hardened plastic material from the mold. The second mold portion 11 has been removed to open the cavity and expose the hardened plastic, which now forms the desired aerosol supply system part 25. Part 25 is removed from the mold portion 10 and includes a textured surface 27 whose surface shape is opposite to that of the opposite textured surface 20 on the mold portion 10. A final finishing step (not shown) can be performed to remove any mold details or other surface defects from the aerosol supply system part 25 and prepare it separately for assembly with other aerosol supply system parts to form a complete aerosol supply system or a component for an aerosol supply system.

[0039] The mold can then be used to repeatedly process other identical aerosol supply system parts (all parts having the same textured surface), thus conveniently providing consistency and reproducibility in the manufacture of aerosol supply systems that allow free liquids (such as water condensates and leaked liquid aerosolizable matrix) to be manipulated.

[0040] Figure 7 An exemplary method according to this disclosure is shown in the form of a flowchart illustrating the method steps, for example, such as... Figures 6A-6F The example illustrates this. In the first step S1, a mold is made of metal having an inner cavity shaped for machining parts for an aerosol supply system. The second step S2 is performed as part of mold manufacturing and includes laser etching using one or more laser beams to define, through an ablation process of the mold's metallic material, a textured surface corresponding to a desired location on the textured surface of the aerosol supply system part at at least a portion of the mold, on the inner surface of the mold cavity. The surface shape of the textured surface is opposite to the desired textured surface of the aerosol supply system part, and this surface shape includes multiple texture features such as recesses / pits / grooves / valves and / or bosses / peaks / protrusions. The size of one or more texture features ranges from 1 µm to 10 µm. This micro-scale textured surface allows for manipulation of liquid movement on the surface of the aerosol supply system through the interaction of surface tension in the liquid with the textured surface, thereby preventing, inhibiting, or guiding the flow of liquid incident on the textured surface.

[0041] In the third step S3, liquid plastic material (the type of plastic from which the aerosol supply system parts are to be made) is injected into the mold to fill the internal cavity of the mold. Appropriate pressure (constant or variable) can be applied to the liquid plastic material to force it into all the recesses in the mold cavity, including micron-sized surface features with opposite textures.

[0042] In step S4, the liquid plastic material is hardened, optionally by utilizing a curing process of the liquid plastic material, or simply by the passage of time during the hardening period. In step S5, the hardened plastic material is released from the mold to obtain an aerosol supply part with a textured surface corresponding to an opposite textured surface defined on the mold. If additional identical aerosol supply system parts are required, step S6 comprises repeating steps S3 through S5 to obtain the desired number of aerosol supply system parts.

[0043] Although the complete manufacturing method for processing aerosol supply system parts includes steps S1 to S5 from the initial manufacture of a suitable mold to the final production of the aerosol supply system parts, by performing... Figure 7A subset of the steps enables another method according to this disclosure. For example, an alternative method for processing aerosol supply system parts includes: employing a suitable mold having a reverse textured surface defined by laser etching, and performing only steps S3, S4, and S5, namely, injecting liquid plastic material into the mold, hardening the liquid plastic material in the mold, and releasing the hardened plastic material from the mold to obtain an aerosol supply system part with a textured surface.

[0044] Furthermore, the method for machining the machined component for processing aerosol supply system parts may only include steps S1 and S2, namely, making a mold for the aerosol supply system parts from metal, and defining an opposite textured surface on at least a portion of the mold using laser etching, wherein the surface shape of the opposite textured surface has micron-sized surface features opposite to the textured surface required for the aerosol supply system parts. In this example, the machined component includes a mold for injection molding to form the aerosol supply system parts by injection molding.

[0045] In another example, the machined part may include an embossing die rather than a mold. In this case, steps S1 and S2 are modified such that step S1 includes an embossing die made of metal for machining an aerosol supply system part with a textured surface. Step S2 includes performing laser etching using one or more laser beams during the step of manufacturing the embossing die to define an opposite textured surface on at least a portion of the embossing die, wherein, as previously described, the surface shape of the opposite textured surface is opposite to the textured surface required for the aerosol supply system part, and the surface shape includes multiple textured features having one or more dimensions ranging from 1 µm to 10 µm. The embossing die can then be used to apply the textured surface to the part by embossing the face of the aerosol supply system part, which is made of a suitable material that can receive surface modification by embossing; in other words, the material is suitably malleable. Metals and plastics can be suitable for this.

[0046] Therefore, more generally, a method for processing a machined part is disclosed, the method comprising: making the machined part from metal; and defining an opposite textured surface on at least a portion of the machined part using one or more laser beams with the laser etching / ablation process described above, wherein the machined part may be a mold for injection molding or may be an embossing mold.

[0047] The type of light source used for laser ablation of metals can be selected based on the type of metal used to make the mold, the amount of material that needs to be removed from the metal to form an opposite textured surface, and the desired speed of the etching process. The technician will know how to select the appropriate light source (the type of laser) and how to operate it in terms of pulse operation, focusing, power, etc., to achieve the desired opposite textured surface etching on the mold section or part of the mold. The technician will understand how to select appropriate parameters and characteristics for one or more laser beams to form the desired textured surface in a given metal.

[0048] Ultrashort laser pulses are commonly used in laser ablation and similar materials processing applications. Due to the shorter light-material interaction time, shorter laser pulses can cause less damage to the surrounding material, and therefore are particularly suitable in this context where the size of the feature to be etched is on the order of micrometers. Pulse durations in the femtosecond range (1 fs–1000 fs) are particularly useful and can be used in this paper. However, longer laser pulses, such as picosecond and nanosecond pulses, can be used where appropriate, and in fact, laser ablation can be performed using continuous-wave (non-pulsed) laser beams if the laser beam intensity is sufficiently high. Therefore, any of these modes can be used.

[0049] Various metals can be used to make molds (and more generally, machined parts), wherein the selection of metal should take into account its suitability for laser etching and its durability in providing mold portions with a contrasting textured surface that will maintain its characteristic features over long periods of repeated use. By way of example only, suitable metals include pre-hardened types of steel with a relatively low carbon content, such as Toolox (RTM) 33, Toolox (RTM) 40, and Toolox (RTM) 44. However, other metals may be used as preferred options.

[0050] Various plastic materials can be used to fabricate aerosol supply system parts, provided they are suitable for injection molding and also for aerosol supply systems. Factors such as heat resistance, tolerance to exposure to aerosolizable matrix materials, safety compliance (e.g., food-grade), and appearance and color may be important. Suitable plastics include readily available polymers such as polycarbonate, acrylonitrile-butadiene-styrene and blends of these two materials, polypropylene, and liquid silicone rubber. Another example is polyetheretherketone (PEEK), which is considered easy to mold and possesses other properties suitable for aerosol supply systems, such as the ability to withstand high temperatures, low thermal conductivity, electrical insulation, zero porosity and exothermic properties, high strength and rigidity, and lead-free properties. However, other plastic materials are not excluded.

[0051] As noted, the liquid plastic material should be injected into the mold under sufficient pressure to ensure proper filling of the mold cavity, thereby reproducing all the micron-level details of the opposite textured surface. The chosen pressure will depend on many variables, including the type of plastic material used, its flow rate, and the geometry and temperature of the mold. Pressure is typically increased with injection time to maintain the flow rate of the plastic material, as the viscosity of the liquid plastic increases flow resistance as it fills the mold. The later stage of the injection process is called holding pressure, during which pressure, rather than flow rate, is controlled so that the flow rate can decrease as the mold cavity fills. The holding pressure can be approximately half the peak injection pressure, but this relationship is unique for each molding process. Technicians will understand how to select and control the required pressure.

[0052] Depending on the type of plastic material chosen, a technician will know what appropriate techniques can be used to harden the liquid plastic material that has entered the mold. As a non-limiting example, a heating system located below the surface of the mold cavity may be included to improve the hydrophobicity of the micron- and nano-scale textured surfaces formed by molding [1].

[0053] While it has been mentioned above that using a mold with an opposite textured surface is advantageous for machining aerosol supply system parts, the laser etching technique described for forming an opposite textured surface on a mold can also be used to directly define a textured surface on the aerosol supply system parts. This may be relevant where a large number of identical aerosol supply system parts are not required (e.g., when small-batch production of a particular design of aerosol supply system is desired), as mold fabrication is considered uneconomical in such cases. Therefore, another method disclosed herein is a method for machining aerosol supply system parts, comprising etching a textured surface having the aforementioned characteristics directly onto the aerosol supply system part using one or more laser beams, specifically consisting of multiple textured features of one or more dimensions ranging from 1 µm to 10 µm.

[0054] The aerosol supply system components can be formed of metal, in which case the parameters of the laser beam used for ablation can be the same as or similar to those given above for etching a surface with opposite texture onto a metal mold. If the aerosol supply system components are made of a non-metallic material (e.g., a plastic material), the parameters and characteristics of the laser beam can be modified accordingly based on the difference between the interaction between light and the plastic material and the interaction between light and the metal.

[0055] In summary, to address various problems and improve the prior art, this disclosure illustrates, by way of description, various embodiments in which the claimed invention can be implemented. The advantages and features of this disclosure are merely representative examples of embodiments and are not exhaustive and / or exclusive. They are intended only to aid in understanding and teaching the claimed invention. It should be understood that the advantages, embodiments, examples, functions, features, structures, and / or other aspects of this disclosure should not be considered as limitations on this disclosure as defined by the claims or on the equivalents of the claims, and other embodiments may be utilized and modifications may be made without departing from the scope of the claims. In addition to those specifically described herein, various embodiments may suitably include various combinations of the disclosed elements, components, features, parts, steps, devices, etc., constitute various combinations of the disclosed elements, components, features, parts, steps, devices, etc., or substantially consist of various combinations of the disclosed elements, components, features, parts, steps, devices, etc. This disclosure may include other inventions not currently claimed but which may be claimed in the future.

[0056] References

[0057] [1]S. Liparoti et al, “Hydrophobicity tuning by the fast evolution ofmold temperature during injection molding”, Polymers 10(3), 15 March 2018

Claims

1. A method for processing parts for an aerosol supply system, comprising: A mold for the part is made of metal, the fabrication comprising defining an opposite textured surface on at least a portion of the mold using one or more laser beams, the surface shape of the opposite textured surface being opposite to the desired textured surface of the part, and the surface shape comprising a plurality of textured features, one or more of the size of the plurality of textured features being in the range of 1 µm to 10 µm; The liquid plastic material to be formed into the part is injected into the mold; To harden the liquid plastic material; as well as The hardened plastic material is released from the mold to obtain the part having the textured surface.

2. A method for processing parts for an aerosol supply system, comprising: Liquid plastic material to be formed into the part is injected into a mold, wherein the mold is formed of metal and includes an opposite textured surface on at least a portion of the mold, the surface shape of the opposite textured surface being opposite to the textured surface required for the part, and the surface shape including a plurality of textured features made by etching the metal using one or more laser beams, the size of one or more of the plurality of textured features being in the range of 1 µm to 10 µm; Harden the liquid plastic material; and The hardened plastic material is released from the mold to obtain the part having the textured surface.

3. The method according to claim 1 or claim 2, wherein, The plastic material includes polycarbonate, acrylonitrile-butadiene-styrene, polypropylene, liquid silicone rubber, or polyetheretherketone.

4. A method for machining a component using a machining center, comprising: A machined part is made of metal for machining a component for an aerosol supply system. The machining process includes defining an opposite textured surface on at least a portion of the machined part using one or more laser beams. The surface shape of the opposite textured surface is opposite to the textured surface required for the component for the aerosol supply system, and the surface shape includes a plurality of texture features, one or more of which are in the range of 1 µm to 10 µm in size.

5. The method according to any one of claims 1 to 4, wherein, The laser comprises pulses with a duration on the order of femtoseconds.

6. A machined part for processing an aerosol supply system component, the machined part being formed of metal, and the machined part including an opposite textured surface on at least a portion thereof, the surface shape of the opposite textured surface being opposite to the textured surface required for the aerosol supply system component, and the surface shape including a plurality of laser-etched textured features, one or more of the plurality of laser-etched textured features being in the range of 1 µm to 10 µm.

7. The method or machined part according to claim 4 or claim 6, wherein, The machined part is a mold used for injection molding.

8. The method or machined part according to claim 4 or claim 6, wherein, The machined component is an embossing mold.

9. The method or machined part according to any one of claims 1 to 8, wherein, The metal includes pre-hardened steel.

10. The method or machined part according to any one of claims 1 to 9, wherein, The opposite textured surface is the opposite of a textured surface that includes a plurality of discrete pits and / or protrusions spaced apart in two dimensions.

11. The method or machined part according to any one of claims 1 to 9, wherein, The opposite textured surface is the opposite of a textured surface that includes multiple parallel grooves and / or ridges.

12. The method or machined part according to claim 11, wherein, The parallel grooves are arranged in a substantially straight line.

13. The method or machined part according to claim 11, wherein, The parallel grooves are arranged concentrically.

14. The method or machined part according to any one of claims 1 to 13, wherein, The size of the texture feature is selected such that the textured surface can inhibit or control the passage of liquid, which is water, on the textured surface of the part.

15. The method or machined part according to any one of claims 1 to 13, wherein, The size of the texture feature is selected such that the textured surface can inhibit or control the passage of liquid on the textured surface of the part, wherein the viscosity of the liquid is greater than that of water.

16. A method for processing parts for an aerosol supply system, comprising: A textured surface is etched directly onto part or all of the surface of a component of an aerosol supply system using one or more laser beams. The textured surface includes multiple texture features, one or more of which have a size in the range of 1 µm to 10 µm.

17. The method according to claim 16, wherein, The part is made of metal.

18. The method according to claim 16, wherein, The part is made of plastic material.

Images