Metal audio speaker grille with multicolor cloth-like appearance and method for manufacturing the same

Abstract

Disclosed is a metal audio speaker grille and related manufacturing method, the metal audio speaker grille having a surface with a cloth-like appearance. The metal audio speaker grille has a base of a metal mesh through which sound can pass; a pretreatment film attached to the base of the metal mesh; and one or more multi-color powder coating films attached to the pretreatment film. In some embodiments, the surface also has antimicrobial properties.

Description

Technical Field

[0001] Certain aspects of the present disclosure relate to metal audio speaker grilles having a multi-colored cloth-like appearance and methods of manufacturing such products. Background Art

[0002] Generally, audio speaker grilles must be an integral part of the automotive interior design theme. The materials used to manufacture such grilles are in close proximity to each other, and the interior design theme includes leather, fabric, hard plastic trim and soft plastic trim, fabric-covered plastic trim, and different metal components with which the audio speaker grilles must visually harmonize.

[0003] Traditionally, the finishes on metal audio grilles have been selected such that they present a significant contrast in finish and texture compared to the rest of the cabin. Historically, OEMs would select a single material / color / tone / finish for the audio grille such that the audio grille contrasted with the rest of the interior. This theme was typically deployed to highlight the brand's premium audio packages and systems.

[0004] More recently, with the shift towards electric propulsion in the automotive industry, there have been plans to reduce weight and streamline interior components. This paradigm shift now more often requires metal audio grilles to substantially mimic the sheen, texture, and color of adjacent fabric or other material patterns to create a harmonious styling theme.

[0005] Metal audio speaker grilles have historically been produced from a variety of metals. These metals include low-carbon steel, aluminum, stainless steel, and alloys of other cost-effective metals with high strength-to-weight ratios. Based on the unique physical properties of each metal and alloy, the base material thickness of the audio grille is typically selected such that there is sufficient strength to withstand wear and tear during manufacturing and after the intermediate product has been transformed into a finished audio grille, after creating an opening area for sound transmission.

[0006] Different methods can be used to generate an opening area for sound transmission in the speaker grille. These opening areas include stamping perforations, laser perforations, waterjet cutting, drilling, photochemical etching, and metal expansion, among others. Each method used to generate the opening area produces a unique metal surface "texture" ranging from relatively smooth to rough / undulating. Depending on which method is selected, generating the opening area for sound transmission can be achieved in a separate metal blank or while the metal is still in roll form. Generating the opening area in a roll typically provides superior economics and production volume. Once the opening area has been generated, the roll or blank of material is transformed into a formed metal grille using traditional metal forming processes, including blanking, stamping, extrusion forming, cam-forming, etc.

[0007] Optionally, the pre-treatment can be considered to clean the cover before subsequent coating or to prevent oxidation of the metal before final finishing. These pre-treatments can range from just surface cleaning to chemical etching (where metal is removed) to the application of physical layers including primers, zinc phosphate, iron phosphate, galvanizing, e-coatings, etc.

[0008] Finishing techniques for metal audio covers have traditionally involved monochromatic or colored coating layers. Finishing techniques for monochromatic coating layers include thermoset powder coating layers, solvent-based paints and enamels, water-based coatings, colored anodized layers, material PVD (Physical Vapor Deposition), colored transparent coating layers, etc.

[0009] Wet spraying involves solvent-based coating systems. These systems include paints and enamels. Historically, they have been applied to various metal components, including audio covers, via a spray gun. These coating layers can be transparent, opaque, or solid in color. Other solid elements can be added to these coating layers to increase color depth, including pearls, metals, and other solid particles. Due to environmental concerns, this type of coating layer is only used when a perfectly smooth surface is required. The wet spraying process cannot provide a multicolor surface that mimics the cloth-like appearance on a metal audio cover.

[0010] Metal anodizing imparts a colored coating layer to the metal surface. The metal component is immersed in a monochromatic chemical reagent that produces an anodic coating layer on the component surface. Similar to the wet spraying method, conventional anodizing processes cannot produce a multicolor surface that mimics the cloth-like appearance on a metal audio cover.

[0011] Traditional PVD techniques involve a single solid color / hue material that evaporates in a vacuum and deposits on the surface of the metal audio cover in a chamber. Similar to the other techniques described above, the PVD process cannot provide a multicolor surface that mimics the cloth-like appearance on a metal audio cover.

[0012] Conventional powder-coated audio covers typically produce a single overall color. Such techniques cannot provide a multicolor surface that mimics the cloth-like appearance on a metal audio cover.

[0013] The prior art discussed above represents conventional methods for generating a single color / hue appearance on metal speaker covers. These traditional finishes lack the ability to mimic the color and texture of a multicolor fabric. Specifically, the surface appearance of automotive speaker grilles made by conventional techniques lacks one or more steps necessary to mimic the appearance of a multicolor fabric. What is desired is an audio speaker grille that is similar to cloth or fabric in terms of color, gloss, surface topography, and other performance requirements.

[0014] The prior art processes only produce a single color coating that does not mimic the appearance of cloth. What the industry desires is a metal audio cover that has the excellent sound quality and durability provided by a metal audio cover, while having the appearance of cloth or fabric and having antimicrobial properties. Summary of the Invention

[0015] Certain aspects of the present disclosure relate to a product and a method for manufacturing a metal audio component or speaker cover having a multicolor cloth-like appearance. Specifically, the disclosed technology balances the key elements necessary to mimic the appearance of a multicolor fabric within a metal audio cover.

[0016] The different process steps include a combination of a multicolor coating, a low gloss, and a metal pattern that have sufficient surface area and surface topography to match the surface area and surface topography of the target fabric. The appropriate combination achieves the goal of a metal audio cover that provides superior acoustic properties and durability of a surface that looks like fabric provided by the metal audio cover.

[0017] The related importance is the ability to provide an antimicrobial finish to these metal audio covers in the painting process. Along with the inherent drawbacks of cloth speaker covers including staining and tearing, the antimicrobial property assumes importance in the context of current and future health issues.

[0018] In a set of preferred process steps, a traditional or non-traditional expanded metal pattern is first selected and an attempt is made to match the surface texture of the target fabric. In addition to the pattern of the metal itself, the film structure of both the pretreatment (if applicable) and the film structure of the multicolor coating must be considered. The combination of the pattern and the layered film structure ideally mimics the target fabric. Additionally, the final finished coating preferably exhibits a gloss level that closely matches the gloss level of the target fabric.

[0019] The above advantages and other advantages and features of the present disclosure will be readily apparent from the following detailed description of the preferred embodiments and process steps when considered in conjunction with the accompanying drawings. Brief Description of the Drawings

[0020] Figure 1 is a perspective view of a representative expanded metal sample before undergoing subsequent processing steps.

[0021] Figure 2 is an expanded view of an expanded metal sample depicting some of its identifying features.

[0022] Figure 3 is a representative process flow diagram.

[0023] Figure 4 is a quarter perspective enlarged top view of a region of a cloth-like multicolor expanded metal audio speaker cover.

[0024] Figure 5 It is an enlarged cross-sectional view of a metal mesh sample encapsulated by a primer film and multi-color paint. Detailed Description

[0025] As those of ordinary skill in the art will understand, the different features of the present disclosure as shown and described with reference to any one of the figures may be combined with the features shown in one or more other figures to produce embodiments not explicitly shown or described in the present disclosure. The combinations of the features shown provide representative embodiments for typical applications. However, different combinations and modifications of the features consistent with the teachings of the present disclosure may be desirable for a particular application or implementation.

[0026] In a series of preferred process steps, a process begins with the selection of a metal mesh pattern. Figure 1 It is an image of a traditional raw metal mesh before exposure to subsequent processing. During metal expansion, an expansion tool uses a bypass shearing process to impart a pattern onto a continuous roll of a malleable alloy such as low-carbon steel or aluminum. Some pattern design elements to be selected include the type or specification of the expansion tool, material thickness, material type, and metal mesh machine process variables / settings, such as Figure 2 those shown in

[0027] A wavy shearing blade with a zigzag pattern (with flat "saw tips") is used to produce a traditional metal mesh pattern. The period between the teeth and the shape of each tooth are some of the factors that affect the pattern matching the surface topography of the target fabric. Changing these factors affects the expansion pattern imparted to the metal. See Figure 2 , representative elements of the 2D / 3D surface matching the surface of the target fabric include SWD (short diameter of the rhombus), LWD (long diameter of the rhombus), as well as SWO (short diameter of the opening) and LWO (long diameter of the opening), ST (strand thickness), and SW (strand width).

[0028] The goal of the disclosed process is to produce a cloth-like metal audio speaker that has the appearance of a fabric (i.e., the properties of the fabric that are directly visible to an observer's eye). This property is related to the surface of the fabric. The fabric appearance is directly related to the fabric construction, weaving, twist, materials used, and the reflective properties of the materials. www.textileadvisor.com / 2019 / 02 / fabric-appearance-fabric-properties-of.html.

[0029] The internal fabric materials of interest are typically multi-colored woven fabrics with a relatively low gloss. There are many weaving patterns. Typically, these patterns are relatively fine, such that the underlying substrate is not visible. Illustrative examples are described at www.midwestfabrics.com / fabrics / automotive-bufforting-fabrics.html, which is incorporated by reference. This source indicates that automotive trim can be characterized by factors such as category (e.g., OEM Detroit number), color (white, gray, black, red, beige, brown, blue, green, brown, purple, and silver), fabric content (polyester, vinyl, fabric, nylon / polyester, and tweed), vehicle make, vehicle year, and price, among others. This source defines automotive trim fabrics for 218 items.

[0030] Figure 3 is a process flow diagram detailing representative steps for configuring an audio cover having a cloth-like appearance.

[0031] Powder coating chemicals, powder color palettes, powder particle size, and additives for controlling gloss are factors affecting the cloth-like appearance. In a preferred embodiment, a specific polyester (TGIC - triglycidyl isocyanurate - a compound used as a curing agent formulated in certain powder coating layers) or polyester urethane chemicals are used. Such chemicals have proven their ability to meet the interior trim automotive performance specifications.

[0032] Figure 5 A representative cross-sectional view of a finished audio speaker grille is depicted. The grille has a substrate that is a metal mesh. On the upper surface of the metal mesh and at least partially penetrating therethrough is a pretreatment film that supports a multi-colored powder coating film. During the electrostatic powder coating painting process step, nearly all of the original metal mesh surface area is encapsulated by the pretreatment film layer. This pretreatment film layer is then preferably completely encapsulated by the multi-colored powder coating film, which has the described cloth-like appearance. The internal Class A surface is the most interesting surface as it is located near the target fabric it is attempting to mimic. By following the disclosed process steps, the surface A-A on the top side of the target fabric is mimicked by the surface B-B of the audio speaker grille. Sound passes through the open spaces formed by the metal mesh grille. Through the metal mesh pattern Figure 5 The cross-sectional view in depicts the layers described herein.

[0033] The main color panel is provided by the OEM to coordinate color matching and color harmonization within a given interior trim system. A powder coating formulation is developed to match the base coat color. This color match is prepared to include a specific particle size distribution. The accent color formulation follows the same initial color matching process; however, the particle size distribution curve is altered to enhance the accent color appearance on the metal grille surface. The desired result is a metal speaker grille that looks like cloth or fabric.

[0034] Details of representative powder coating process parameters and powder coating troubleshooting guidance can be found at www.tcipowder.com / resources / troubleshooting-guide / chapter-eleven-powder-curing-process and are incorporated herein by reference.

[0035] Subject the wire mesh to one or more pretreatment steps to enhance the adhesion of the powder to the wire mesh substrate. Suitable pretreatment enables durable corrosion resistance. Such pretreatment steps typically include cleaning the substrate to remove, for example, contaminants and oil, rinsing, and chemically converting and rinsing the substrate surface. Such conversion can, for example, involve chromate conversion of aluminum and iron phosphate for ferrous metals.

[0036] Most conversion coatings include a film that changes the physical and chemical properties of the wire mesh surface. Typically, the film can exhibit an iridescence from gray to blue or from blue to gold.

[0037] Gloss is measured by irradiating a known amount of light on the surface and quantifying the reflectance. www.gloss-meters.com / Glosslntro2.html. Most automotive interior fabrics have a low gloss level typically in the range of 3 - 9% at a 60-degree viewing angle. In a preferred embodiment, the wire mesh audio grille with a finished cloth-like powder coating that most closely matches the fabric system has a gloss level of 5 - 7% at a 60-degree viewing angle. Those skilled in the art will understand that the gloss chemical formulation and the final gloss appearance can be adjusted up or down according to the desired appearance of the finished audio grille. Process variables for manufacturing a cloth-like metal speaker grille include surface texture, the number of powder particle colors, the size of the powder particles, the ratio of color and particle size, and the average gloss level.

[0038] The goal is to provide features that harmonize with a given interior design theme. Ideally, one result is a soft cloth-like appearance created by a multicolored, speckled appearance that mimics the perceived 2D / 3D dimensions of a dyed fabric. In contrast, traditional methods produce a single-color coating that does not resemble a cloth-like appearance.

[0039] In one method, a metal audio grille is processed through an electrostatic powder coating system that applies a developed chemical to match the color and gloss of a target fabric. This powder coating chemical needs to be applied during a suitable film building stage and then cured, preferably using a two-stage curing system in a controlled manner. It has been found that this controlled application and curing system provides consistent color, suitable gloss, a satisfactory appearance, and other performance characteristics. Such characteristics include, in addition to having a color and appearance texture that match the master sample, resistance to various solvents, cleaners, salt spray, abrasion, scratch and scuff damage, antimicrobial properties, and scuff resistance. If desired, one or more films can be applied by the powder coating method.

[0040] As used herein, the term "antimicrobial" refers to a property or coating that contains an active ingredient that renders it effective against the growth of bacteria and fungi. Antimicrobial coatings can include solvent-based, water-based, liquid, or powder coatings. See, for example, www.microban.com / antimicrobial-solutions / applications / antimicrobial-paints. Suitable formulations can be obtained from sources such as Microban, www.microban.com. Antimicrobial agents can be added to one or more of the pretreatment film and / or the multi-color powder coated film.

[0041] The methods described herein use alternative coating techniques and chemicals to bring the manufacture of enhanced audio grilles to a new level in terms of simulating texture and a fabric-like appearance. Such techniques result in audio grilles that provide a fabric-like finish that matches the styling theme.

[0042] At least some of the advantages of the disclosed process steps include:

[0043] Low cost

[0044] Excellent durability

[0045] No adhesives are required (unlike fabric-covered grilles)

[0046] Convex and concave shapes that cannot be achieved with fabric are possible with fewer components, reducing system-level complexity.

[0047] Tests have shown that fabric-coated plastic audio grilles and the disclosed powder-coated audio grilles with a fabric-like appearance have close similarities. The average observer cannot easily distinguish between the surface color, texture appearance, and gloss levels of each other.

[0048] Although the best mode has been described in detail, those skilled in the art will recognize that different alternative process steps, designs, and embodiments fall within the scope of the following claims. While various embodiments may be described as providing advantages over one or more desired features or being preferred to other embodiments, as will be appreciated by those skilled in the art, one or more features may be compromised to achieve the desired system attributes, depending on the particular application and implementation. These attributes include, but are not limited to: cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, durability, weight, manufacturability, ease of assembly, etc. With respect to one or more features, embodiments described herein as less desirable than other embodiments or prior art embodiments do not exceed the scope of the disclosure and may be desirable for a particular application.

Claims

1. A metal audio speaker grille, comprising: A base of a metal mesh; A pretreatment film, the pretreatment film being attached to the base of the metal mesh; A multi-color powder coating film, the multi-color powder coating film being attached to the pretreatment film, and the surface of the multi-color powder coating layer has a cloth-like appearance; wherein, the multi-color powder coating film includes a coating formulation developed to match the base coating color, and the coating formulation includes an initial predetermined particle size distribution.

2. The metal audio speaker cover according to claim 1, wherein, The base of the metal mesh is characterized by factors of the minor axis of a rhombus, the major axis of a rhombus, the minor axis of an opening, the major axis of an opening, the wire thickness of the mesh, and the wire width of the mesh.

3. The metal audio speaker cover according to claim 1, wherein, The base of the metal mesh includes a material selected from low-carbon steel alloy, aluminum, aluminum alloy, stainless steel, and compositions of the low-carbon steel alloy, the aluminum, the aluminum alloy, and the stainless steel.

4. The metal audio speaker cover according to claim 1, wherein, The base of the metal mesh includes openings that do not have the pretreatment film and the multi-color powder coating film to allow sound to pass through the audio speaker grille.

5. The metal audio speaker grille according to claim 1, further comprising one or more antimicrobial agents.

6. The metal audio speaker cover according to claim 1, wherein, The pretreatment film cleans the base of the metal mesh before one or more subsequent coating layers are applied, and the pretreatment film includes a physical layer having a composition selected from primer, zinc phosphate, iron phosphate, electroplated material, and electrocoating layer.

7. The metal audio speaker cover according to claim 1, wherein, The multi-color powder coating film has an outer surface similar to automotive fabric or cloth-like material.

8. The metal audio speaker cover according to claim 1, wherein, The multi-color powder coating film further includes one or more subsequent color formulations, and each of the one or more subsequent color formulations has a particle size distribution curve different from the initial predetermined particle size distribution to enhance the auxiliary or subsequent color appearance on the surface of the metal grille.

9. The metal audio speaker grille according to claim 1, further having an outer surface facing the observer, and the outer surface is characterized by a glossiness, texture, and color that simulate the corresponding properties of adjacent fabric, and the glossiness has a glossiness level of 5% to 7% at a 60-degree viewing angle.

10. A method of manufacturing a metal audio speaker grille, the method including the following steps that are not necessarily implemented in the presented order: Providing a base of a metal mesh; Attaching a pretreatment film to the base of the metal mesh; And Powder coating one or more multi-color films attached to the pretreatment film, and the surface of the one or more multi-color powder film coating layers has a cloth-like appearance; Wherein, the powder coating step includes using a coating formulation that matches the base coating color and selecting an initial predetermined particle size distribution.

11. The method according to claim 10, wherein, The powder coating step further includes using one or more subsequent color formulations, and each of the one or more subsequent color formulations has a particle size distribution curve different from the initial predetermined particle size distribution to enhance the auxiliary or subsequent color appearance on the surface of the metal grille.

12. The method according to claim 11, wherein, The powder coating step further includes providing an outer surface facing the observer, and the outer surface is characterized by a glossiness, texture, and color that simulate the corresponding properties of adjacent fabric.

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