Method for manufacturing an electrical device with a light indicator

Abstract

The invention relates to a method for manufacturing an electrical device (10) with a light indicator (14, 16), comprising a housing (18) and a light source (22) arranged in the housing (18), the light source being configured to couple light into a housing wall (20) of the housing (18), which propagates through the material of the housing wall (20) to a light-extracting part (24) of the housing (18), through which the light emitted by the light source (22) can exit the housing (18), wherein the light indicator (14, 16) is formed by at least the light-extracting part (24) of the housing (18), wherein the light-extracting part (24) of the housing (18) or a non-light-extracting part (26) of the housing (18) that delimits the light-extracting part (24) of the housing (18) is produced by a local mechanical, chemical and / or physical treatment of the housing (18). is,the treatment is carried out with the electrical device (10) in a fully assembled state.

Description

[0001] The invention relates to a method for producing an electrical device with a light display.

[0002] In state-of-the-art electrical devices, LEDs are often used to signal operating states. For example, states such as power on, errors, or specific functions can be indicated. To create the illuminated indicator, appropriate openings are made in the housing that surrounds and protects the electrical device. These openings are either directly connected to the LEDs or to light guides that interact with the LEDs.

[0003] Alternatively, housings can also be designed with at least partially transparent areas. For example, DE 602 15 391 T2 and EP 1 619 937 B1 disclose housings for electrical or electronic devices that are at least partially transparent, allowing light from a light source installed inside the housing to escape to the outside.

[0004] From EP 2 322 962 A1, a decorative element is also known which has a body which serves to transport light and in which coupled-in light changes its propagation direction at least once in order to reach a coupling-out region.

[0005] Special display symbols can be created, for example, using masks, which are usually made of an opaque layer. This layer can be a colored layer or made of a perforated or punched material.

[0006] Conventional illuminated displays are typically manufactured using tool-based parts. A custom-designed tool is required for each new optical configuration of the illuminated display. Thus, either the light guides must be manufactured in the appropriate shape and integrated into the housing, or light guides already present in the housing must be partially covered, e.g., by printing, especially pad printing. Because this is technically complex, it is often not economically viable, especially for small batch sizes or special products with a customized display.

[0007] The object of the invention is therefore to provide an electrical device with a light display that is technically easy to implement and that can be manufactured cost-effectively even in small to medium batch sizes.

[0008] The object is achieved according to the invention by a method according to claim 1 for producing an electrical device with a light display.

[0009] The electrical device comprises a housing and a light source arranged in the housing. The light source is configured to couple light into a housing wall of the housing, which propagates through the material of the housing wall to a light-outcoupling part of the housing, through which the light emitted by the light source can exit the housing. The illuminated display is formed by at least the light-outcoupling part of the housing. The light-outcoupling part of the housing or a non-light-outcoupling part of the housing that delimits the light-outcoupling part of the housing is produced by a local mechanical, chemical and / or physical treatment of the housing, wherein the treatment takes place when the electrical device is fully assembled.

[0010] A "fully assembled state" means that all components of the electrical device are already connected to one another, i.e., mechanically and / or electrically. In other words, in a fully assembled state, at least the hardware components are fully contained within the housing. Configuring the electrical device and / or installing software, especially customized software, does not constitute assembly in this sense and can also occur after the electrical device's LED display has been manufactured.

[0011] The basic idea of ​​the invention is to produce the illuminated display only after the electrical device has been fully assembled, without penetrating the housing, i.e., without creating a perforation or a through-hole in the housing. Furthermore, the housing does not need to be subsequently opened. This allows for a high degree of customization of the illuminated display and, at the same time, ensures that the components of the electrical device housed in the housing are always adequately protected, especially against moisture.

[0012] This also makes it possible to produce the electrical devices in a basic state in large quantities. The respective electrical device, which is fully assembled and in its basic state, can then be individually customized to the customer with regard to the light display, particularly the light-emitting part. This results in correspondingly short production times and low manufacturing costs for special products or small batch sizes.

[0013] In particular, this type of manufacturing ensures that the protection standards required depending on the device type or application are met, for example the protection standard IP44, IP67 and / or IP 69K, which is required for numerous devices.

[0014] In one embodiment, the light-coupling part of the housing is formed by modifying the housing wall. The interior of the electrical device and the electrical or electronic components or parts located therein remain protected during treatment, especially from residues that may form during the treatment itself, such as chips or steam.

[0015] The material of the housing wall can be a plastic material containing additives designed to locally modify the optical properties of the material through mechanical, chemical, and / or physical treatment in order to form the light-outcoupling part of the housing, particularly in a defined manner. The additives can be used to customize the illuminated display in a defined manner, since the additives are excited, for example, by a laser to adjust a degree of translucency. Furthermore, the housing comprising the plastic material can be manufactured quickly and cost-effectively, for example, by injection molding.

[0016] Preferably, the light-coupling part of the housing and the non-light-coupling part of the housing are connected to each other by a continuous material connection. This avoids potential weak points at the transition between the two parts.

[0017] In one variant of the electrical device, at least the light-coupling part of the housing comprises at least one optical scatterer. The optical scatterer scatters the light incident on it in the housing wall, thereby achieving effective light extraction from the housing wall.

[0018] The at least one optical scatterer can be a three-dimensional structure that has been introduced into the housing wall by the treatment, e.g., a recess in the housing wall. Alternatively, the at least one optical scatterer can be a material-modified region introduced into the housing by the treatment. For example, laser treatment can locally modify the plastic material of the housing wall (partially decomposed, crystallized, etc.), forming opaque regions in the housing wall that scatter the light and thus enable or improve the light extraction from the housing.

[0019] In principle, the additives mentioned above can also be considered as interference with the housing structure, where light is reflected or scattered when coupled into the housing. Therefore, the additives can also (additionally) function as scatterers. The light-outcoupling part can arise in the area of ​​the additives.

[0020] It is also conceivable for the housing to completely and / or completely enclose the interior of the electrical device, so that all intended electrical or electronic components are accommodated within the housing. Only one or more connections are attached to the outside of the housing for connecting the electrical device or to other devices. This ensures particularly good protection of the electronic components and achieves a high level of protection.

[0021] The method according to the invention for producing the electrical device comprises the steps: - Providing an electrical device in a fully assembled state, which has a housing in which all electrical or electronic components of the electrical device are accommodated; - Production of a light-coupling part of the housing by a local mechanical, chemical and / or physical treatment of the housing in the fully assembled state.

[0022] The advantages discussed for the electrical device apply equally to the method according to the invention.

[0023] In one variant of the method, the treatment of the housing is carried out by mechanical removal and / or laser ablation of an opaque cover layer of the housing. Alternatively or additionally, the local treatment of the housing can be carried out by selective exposure, in particular by means of a laser, which changes the optical properties of the housing material. For example, local light scatterers can be created in the housing wall and / or the housing material can be changed so that it becomes more opaque or transparent. All of these measures can be applied to the fully assembled electrical device in order to quickly and cost-effectively implement an illuminated display in the housing wall without having to break through the housing or create a breakthrough in the housing.

[0024] It is also conceivable that, before or after manufacturing the light-coupling part of the housing, only software associated with the light-coupling part of the housing is installed to produce the ready-to-use electrical device. This makes it technically simple to produce a customized electrical device cost-effectively and also identifiable as such based on the light-coupling part of the housing or the illuminated display.

[0025] The cost-effective production of customized electrical devices is possible because the electrical devices are initially manufactured in large quantities (large batches) in a basic state, i.e., in a fully assembled state, with all electrical and / or electronic components already incorporated into the housing. The fully assembled electrical device can then be individually customized to the customer with regard to the illuminated display, particularly the light-coupling part. However, the tools used to manufacture the electrical devices are the same, since the tools are used to manufacture the electrical device in its basic state, i.e., in a fully assembled state.

[0026] In other words, it is not necessary to provide separate tools for production in order to achieve the desired customization, which would result in correspondingly high costs for small quantities (small batches or special products).

[0027] Further features and advantages of the invention will become apparent from the following description and the drawings, to which reference is made. In the drawings: - Fig. 1 shows a schematic three-dimensional representation of an electrical device according to an exemplary embodiment, which has been manufactured according to a method according to the invention; - Fig. 2 a schematic three-dimensional representation of a manufacturing step of a light-coupling housing part of the electrical device by laser treatment; - Fig. 3 a schematic three-dimensional representation of a manufacturing step of a light-coupling housing part of the electrical device by mechanical processing; - Fig. 4 is a schematic sectional view of a portion of the housing of the electrical device with a recess acting as a spreader; and - Fig. 5 a schematic sectional view of a portion of the housing of the electrical device with optical scatterers within the housing wall.

[0028] Fig. 1 shows a schematic three-dimensional representation of an electrical device 10. In the embodiment shown, the electrical device 10 is an electronic module, in particular for industrial applications.

[0029] The electrical device 10 has a plurality of connections 12 and connection-specific LED indicators 14, i.e., LED indicators 14 that can indicate the status of the associated connection 12. Furthermore, the electrical device 10 also has a module-specific LED indicator 16, which can, for example, display information about a configuration or software of the electrical device 10, i.e., generally, information regarding the entire electrical device 10.

[0030] The outer shell of the electrical device 10 is formed by a housing 18 with a housing wall 20. In the exemplary embodiment, the housing 18 is made of a transparent injection-molded plastic material. On the outside, the housing 18 or the housing wall 20 is at least partially coated with an opaque material, for example, painted.

[0031] The housing 18 encloses the electrical device 10 completely and on all sides, except for openings for the connections 12.

[0032] All electrical / electronic components of the electrical device 10 are housed in the housing 18. This protects them from environmental influences such as dust or moisture.

[0033] To realize the illuminated display 16, the electrical device 10 has a light source 22 inside the housing 18, for example a light-emitting diode or a light-emitting diode array.

[0034] In the exemplary embodiment, the light source 22 is designed and configured to couple light into the housing wall 20 of the housing 18. The light can be coupled into the housing 18, for example, through a side wall and / or a specially shaped coupling region 23 of the housing 18. A light guide can also be provided, with which the light is guided from the light source 22 to the coupling region 23 of the housing 18. The light coupled via the coupling region 23 of the housing 18 then propagates through the material of the housing wall 20.

[0035] The housing wall 20 has a light-coupling part 24 which forms the illuminated display 16 and through which the light from the light source 22 propagating in the housing wall 20 can exit the housing wall 20.

[0036] Furthermore, the housing wall 20 has a non-light-coupling part 26, for example made of opaque or opaque-coated plastic, which delimits the light-coupling part 24 of the housing 18.

[0037] The shape, size and / or assignment of the light-coupling part 24 and the non-light-coupling part 26 allows symbols and the like to be realized on the outside of the housing 18.

[0038] In the exemplary embodiment, the light-coupling part 24 and the non-light-coupling part 26 are formed as a continuous injection-molded component and are thus materially connected to one another, i.e., integrally formed. This makes the transition between the two parts 24, 26 particularly robust.

[0039] In the exemplary embodiment, the light-coupling part 24 of the housing 18 was produced in a fully assembled state of the electrical device 10 by locally treating the housing 18 with a laser 28, i.e., after all electrical or electronic components had already been incorporated into the housing 18. The electrical or electronic components were connected both mechanically and electrically.

[0040] The manufacturing step of the local treatment is shown schematically in Fig. 2 shown.

[0041] As can be seen from the illustration, the light-coupling part 24 of the housing 18 is formed by a local modification of the housing wall 20, namely by partially removing an opaque cover layer 30 of the housing 18. The cover layer 30 is preferably located on the outside of the housing. Alternatively, it can also be attached to the inside of the housing.

[0042] The cover layer 30 itself can be applied by various methods, in particular by a two-component injection molding process, painting, printing or foiling by heat sealing or in-mold labeling (IML).

[0043] Alternatively, the light-coupling part 24 of the housing 18 may also have been produced by a local chemical treatment or mechanical processing of the housing 18 in a fully assembled state of the electrical device 10.

[0044] Fig. 3 shows such a mechanical treatment or processing in which an opaque cover layer 30 of the housing 18 is removed by means of a milling tool 32 in order to partially expose the underlying transparent plastic material.

[0045] The Fig. 2 and Fig. The types of treatment of the housing 18 shown in Figure 3 are, of course, not intended to be limiting. Material removal by waterjet engraving, planing, or similar methods is also conceivable.

[0046] It is also possible for the housing 18 to be made of a material that includes additives designed to locally modify the optical properties of the material through mechanical, chemical, and / or physical treatment in order to form the light-coupling part 24 of the housing 18. In other words, the translucency of the additives is modified, for example, by laser irradiation, whereby the area in which the additives are provided becomes more opaque or transparent, which ultimately depends on the laser used and / or the additives.

[0047] For example, the material can be a plastic whose opacity can be locally adjusted from transparent to completely opaque by treatment with a laser 28, particularly by stimulating the additives it contains. This also allows backlit symbols and / or lettering in the illuminated display 16 to be manufactured quickly and easily.

[0048] The light-coupling part 24 of the housing 18 can also be formed by introducing local impurities and / or optical scatterers 34 into the housing wall 20 during the treatment, which couple the light out of the housing wall 20. The additives could also function as such scatterers 34, if desired.

[0049] In Fig. Figure 4 shows a sectional view of a section of a housing 18 in which light from the light source 22 is coupled into the housing wall 20, in particular via a side wall of the housing 18. The housing wall 20 is designed, through the material selection and construction, such that the coupled-in light is guided to the light-outcoupling part 24 of the housing 18. In this respect, the light can be coupled in at a point on the housing 18 that is spaced apart from the light-outcoupling part 24 of the housing 20. In other words, the coupling region 23 is spaced apart from the light-outcoupling part 24. The housing 18 or the housing material thus represents a light guide.

[0050] The light-coupling part 24 is located, for example, on a front side of the housing 18. In the exemplary embodiment, the housing 18 has a surface 36 at which the coupled-in light is reflected. The surface 36, which can therefore also be referred to as a reflection surface, is aligned at an angle of 45° to the side wall and the front side of the housing 18 in the exemplary embodiment shown. Due to the angle and the light refraction properties of the housing material, total reflection occurs at the surface 36, so that the coupled-in light is (essentially) completely guided from the side wall to the front side of the housing 18, as shown in Fig. 4 is shown.

[0051] The housing 18 can thus be designed such that total internal reflection of the coupled light occurs in some areas within the housing wall 20. This allows a luminous flux to be generated in the housing wall 20 that runs parallel to the display plane (regardless of the coupling). The coupling region 23 and the light-coupling part 24 of the housing 20 can thus be spatially separated from one another.

[0052] In the Fig. In the example shown in Figure 4, the light is coupled out through a three-dimensional structure 38 (in this case, a recess 40), which was created by a local treatment (for example, by milling, engraving, or embossing using needles) in the housing wall 20 or a surface section of the housing wall 20 and at which the light is scattered. This scattering allows at least part of the luminous flux to be coupled out of the housing 18.

[0053] Alternatively or additionally, material-modified regions 42 can be provided in the housing 18, which act as optical scatterers 34. This is shown in Fig. 5. As explained above, the spreaders 34 may also be additives.

[0054] The material-modified areas 42 may, for example, be partially decomposed or partially crystallized opaque areas 44 in an otherwise transparent plastic matrix, which have been deliberately created by the local treatment, for example by irradiating the additives.

[0055] The precisely positioned diffusers 34 allow for very precise light emission from the luminous flux of the housing wall 20, creating very fine symbols or lettering. Another advantage of this type of light extraction is that there is little or no weakening of the housing material. Furthermore, the housing 18 has a continuous outer surface, preventing deposits from accumulating. For this reason, this method is particularly suitable for applications where cleanliness and purity are of paramount importance, for example, in the food or pharmaceutical industries.

[0056] The Fig. The electrical device 10 with illuminated display 16 shown in Figure 1 was manufactured using an embodiment of a method according to the invention. The method and its steps are briefly explained below.

[0057] In a first step of the method, an electrical device 10 is provided in a fully assembled state, comprising a housing 18 in which all electronic / electrical components of the electrical device 10 are accommodated. The hardware is therefore already fully installed, so that the electrical device 10 is in a basic state that is the same for all electrical devices 10, so that one tool or tool set is sufficient to manufacture the electrical devices 10.

[0058] In a second step of the method, a light-coupling part 24 of the housing 18 is produced by a local mechanical, chemical and / or physical treatment of the housing 18 in the fully assembled state, i.e. in the state in which the hardware is completely installed.

[0059] The local treatment of the housing 18 can, as already shown in the Fig. 2 and Fig.3, by mechanically removing and / or laser ablating an opaque cover layer 30 of the housing 18.

[0060] Alternatively or additionally, the local treatment of the housing 18 can be carried out by selective exposure, in particular by means of a laser 28, which changes the optical properties of the material of the housing 18. Thus, it is conceivable that the opacity of a housing 18 made of a plastic material with special laser-active additives can be locally and specifically changed by the laser treatment in order to define light-outcoupling parts 24 and / or non-light-outcoupling parts 26 of the housing 18 and thus form the illuminated display 16.

[0061] In a further step of the method, software can be loaded onto the electrical device 10 before or after the production of the light-coupling part 24 of the housing 18. The software to be loaded can, in particular, be assigned to the light-coupling part 24 of the housing 18 to ensure that, in certain operating states, the light is coupled out via the light-coupling part 24 of the housing 18, i.e., that the light source 22 is controlled accordingly. For example, the illuminated display 16 can be designed to indicate the device type and / or the device function defined by the software. List of reference symbols 10 electrical device 12 connection 14 connection-specific LED indicators 16 module-specific LED indicators 18 housings 20 Housing wall 22 Light source 23 Coupling area 24 light-coupling part 26 non-light-coupling part 28 lasers 30 top layer 32 milling tools 34 spreaders 36 Surface 38 Structure 40 recess 42 material-changed area 44 opaque spots

Claims

[1] A method for producing an electrical device (10) with a light display (14, 16), comprising a housing (18) in which all electrical and / or electronic components of the electrical device (10) are accommodated, and a light source (22) arranged in the housing (18) which is designed to couple light into a housing wall (20) of the housing (18), which light propagates through the material of the housing wall (20) to a light-outcoupling part (24) of the housing (18), through which the light emitted by the light source (22) can exit the housing (18), wherein the light display (14, 16) is formed by at least the light-outcoupling part (24) of the housing (18), comprising the steps: - providing the electrical device (10) in a fully assembled state; and - producing the light-coupling part (24) of the housing (18) by a local mechanical, chemical and / or physical treatment of the housing (18) in the fully assembled state. [2] Method according to claim 1, wherein the light-coupling part (24) of the housing (18) is formed by a change in the housing wall (20). [3] Method according to claim 1 or 2, wherein the material of the housing wall (20) is a plastic material comprising additives, wherein the additives locally change the optical properties of the material through the mechanical, chemical and / or physical treatment in order to form the light-coupling part (24) of the housing (18). [4] Method according to one of the preceding claims, wherein the housing (18) has a non-light-coupling part (26) which is materially continuously connected to the light-coupling part (24) of the housing (18). [5] Method according to one of the preceding claims, wherein at least the light-coupling part (24) of the housing (18) comprises at least one optical scatterer (34). [6] Method according to claim 5, wherein the at least one optical scatterer (34) is a three-dimensional structure (38) which is introduced into the housing wall (20) by the treatment, in particular a recess (40), and / or wherein the at least one optical scatterer (34) is a material-modified region (42) introduced into the housing (18) by the treatment. [7] Method according to one of the preceding claims, wherein the housing (18) encloses an interior of the electrical device (10) completely and / or on all sides. [8] Method according to one of the preceding claims, wherein the local treatment of the housing (18) is carried out by mechanical removal and / or laser ablation of an opaque cover layer (30) of the housing (18) and / or wherein the local treatment of the housing (18) is carried out by selective exposure, in particular by means of a laser (28), by which the optical properties of the material of the housing (18) are changed. [9] Method according to one of the preceding claims, wherein before or after the production of the light-coupling part (24) of the housing (18) only a software is loaded which is assigned to the light-coupling part (24) of the housing (18) in order to produce the ready-to-use electrical device (10).

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