Enclosure for electronic circuitry

Abstract

Enclosure (100) for an electronic module. A first part (101) has a first flat surface, a circular inner sidewall (104) with outside threads (105), a first flange (108) provided on the flat surface and encircling the circular sidewall (104), and provided with one or more features (404) configured to secure the electronic module (401) in place inside the enclosure. A second part (102) has a second flat surface, a circular outer sidewall (106) with inside threads (107) matching the outside threads (105) of the first part (101), a second flange (109) along the rim of the outer sidewall (106). The first part (101) and the second part (102) are made from a single material. The combination of features ensures that the enclosure is watertight without addition of seals or gaskets, and the electronic component (401) is secured in place without any additional fastening devices or materials.

Description

ENCLOSURE FOR ELECTRONIC CIRCUITRYTECHNICAL FIELD

[0001] The present invention relates to an enclosure for electronic circuitry and more particularly, to an enclosure with limited use of different types of materials in order to facilitate servicing and recycling. In particular, the invention relates to such enclosures produced using substantially only one material and configured for easy assembly and disassembly.BACKGROUND

[0002] With the advent of the Internet of Things (loT), electronic circuitry in the form of sensors, tracking devices, positioning means, identifying tags, and the like, are being attached to a wide variety of different assets and items. Such circuitry is typically mounted in small enclosures, or housings, where they are attached with glue, screws, snap-fit spacers, locking members with protrusions configured to snap into place and hold the enclosed circuitry or different parts of the enclosure in place, and so on. Common problems with these types of enclosures include difficulties associated with opening, removing, and replacing parts, and resealing the enclosure due to use of screws that require use of tools, snap-fit features that are only designed for mounting, not for removing, and that may require special tools or might break upon disassembly. Glue and potting make servicing or replacement of components close to impossible.

[0003] For recycling purposes these problems are even more substantial. Enclosures made from one material but including fasteners such as screws from a different material, and perhaps with seals, potting and glue adding to the mix of materials makes separation and sorting of different materials for recycling expensive and perhaps economically unviable.

[0004] Consequently, there is a need for enclosures that provide the necessary physical properties in terms of durability, protection of the enclosed components from the environment, etc., and at the same time providing easy access for servicing or replacing parts and facilitating reuse of the enclosure or recycling of the material from which the enclosure is produced.SUMMARY OF THE DISCLOSURE

[0005] In order to address the needs mentioned above an enclosure for an electronic module has been developed. The enclosure includes a first part with a first flat surface, a circular inner sidewall with outside threads, a first flange provided on the flat surface and encircling the circular sidewall and provided with one or more features configured to match the general shape of the electronic module, to match at least one corresponding feature in the electronic module, or to provide support for at least one surface of the electronic module. Asecond part has a second flat surface, a circular outer sidewall with inside threads matching the outside threads of the first part, and a second flange along the rim of the outer sidewall. The first part and the second part are made from a single material. The second flange is configured to fit between the inner sidewall and the first flange when the first part and the second part are screwed together by way of the outside threads and the inside threads.

[0006] In some embodiments the outer diameter of the second flange is smaller than the inner diameter of the first flange at least along a circle where the two flanges meet when the first part and the second part are screwed together, such that the second flange will be deformed by being pressed inwards by the first flange.

[0007] Embodiments of the invention may also include a third part configured to hold at least one battery and to, when it is positioned inside the enclosure and holding the at least one battery, direct forces to parts of the enclosure that can absorb the forces without damage to the electronic component.

[0008] In enclosures according to the invention forces may be directed through the electronic module and be absorbed on one side by a feature in the first part configured to provide support for at least one surface of the electronic module and on an opposite side by the third part configured to hold at least one battery, which in turn is configured to, directly or indirectly, direct forces to the second part. The third part configured to hold at least one battery may be configured to direct forces to the second part through the at least one battery.

[0009] In embodiments of the invention the second flat surface, on the second part, may be provided with at least a region which stretches towards the first flat surface, on the first part. This region may then subject pressure on components inside the enclosure when such components have dimensions corresponding to the distance between the first surface and the second surface when the enclosure is assembled.

[0010] In some embodiments at least one of the one or more features configured to match the general shape of the electronic module, to match at least one corresponding feature in the electronic module, or to provide support for at least one surface of the electronic module, is configured as a locking member which will hold the electronic module in place when it is inserted into the enclosure, and which is configured to absorb forces that are parallel to the first surface and the second surface.

[0011] One or more of the features configured to match the general shape of the electronic module, to match at least one corresponding feature in the electronic module, or to provide support for at least one surface of the electronic module, are configured to hold the electronic module in place without additional fastening material such as screws, glue, and potting.

[0012] The one or more features configured to match the general shape of the electronic module, to match at least one corresponding feature in the electronic module, or to provide support for at least one surface of the electronic module, may be integral parts of the first partcreated as part of the same process, and selected from the group consisting of: notches, guides, slots, recesses, taps, ridges, grooves, tabs, brackets, spacers, and pins.

[0013] The first part and the second part may be manufactured using injection molding.

[0014] The first part and the second part may be manufactured with a precision sufficient to ensure that the enclosure is watertight when assembled without addition of any gasket, seal, or additional component made from a material different from said single material.BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The invention will now be described in further detail by means of exemplary embodiments and features illustrated in the attached drawings, which show:

[0016] FIG. la an enclosure according to the invention;

[0017] FIG. lb a cross sectional view corresponding to the view in FIG. la;

[0018] FIG. 2 a sectional side view of an enclosure according to the invention;

[0019] FIG. 3 a sectional view of certain details of a partially assembled enclosure according to the invention;

[0020] FIG. 4 the bottom part of an enclosure according to the invention with an electronic component or module inserted;

[0021] FIG. 5 a cross-sectional view of an enclosure with an inserted electronic module and where the bottom part and the top part are assembled;

[0022] FIG. 6 a top view of the bottom part of an enclosure with an inserted electronic module; and

[0023] FIG. 7 a cross-sectional view of the bottom part and the top part of the assembled enclosure without any inserted electronic module.DETAILED DESCRIPTION

[0024] The present invention represents a response to the need for enclosures for electronic components and the like that fulfill a number of requirements that often are competing. In particular, an enclosure should be easy and cheap to manufacture, it should allow for efficient production int terms of insertion of the components it is intended to hold, it should hold the inserted components securely in place and protect them from the environment, it should be easy to open and close during production as well as when being serviced, and it should be easy to dispose of after it is no longer needed, preferably in a manner that allows for recycling or reuse of materials.

[0025] In the following description of embodiments of an enclosure configured to meet these needs, reference will be made to the drawings, in which like reference numerals denote the same or corresponding elements. The drawings are not necessarily to scale. Instead, certain features may be shown exaggerated in scale or in a somewhat simplified or schematic manner, wherein certain conventional elements may have been left out in the interest of exemplifying the principles of the invention rather than cluttering the drawings with details that do not contribute to the understanding of these principles.

[0026] It should be noted that, unless otherwise stated, different features or elements may be combined with each other whether or not they have been described together as part of the same embodiment below. The combination of features or elements in the drawings are intended to facilitate understanding of the invention rather than limit its scope to specific embodiments, and to the extent that alternative elements with substantially the same functionality are shown in respective embodiments, they are intended to be interchangeable. Similarly, if certain details, feature, or elements are explained with reference to one particular drawing, that same detail, feature or element may be included in any other embodiment even if not shown in another drawing, as long as such a detail, feature, or element is not mutually exclusive with respect to a detail, feature, or element included in that other drawing.

[0027] However, for the sake of brevity no attempt has been made to disclose a complete description of all possible permutations of features. As such, the different drawings do not represent distinct embodiments in the sense that they are exclusive alternatives to each other. Instead, the drawings focus, for example, on different aspects, different levels of detail, or different views or perspectives. Alternative embodiments to those shown in the drawings are arrived at by adding features, by removing features, or by configuring features in a different arrangement than those shown in the exemplary drawings. Unless features are explicitly identified as required or they functionally depend on each other to function they may be omitted, reconfigured, or made to interoperate with additional features not described herein, in any manner that is within the capabilities and knowledge of a skilled person having studied this disclosure. Similarly, if features are described with different levels of detail in sections referencing different drawings, this is not meant to imply that embodiments are constituted either by the lower level of detail or with the higher level of detail. Instead, details described with reference to one drawing are intended to be understood as being available but not necessarily mandatory in embodiments, such that none, some, or all features of a detailed example may be imported into a less detailed description unless otherwise stated or unless they clearly depend on each other for their intended operation. In other words, different aspects that include design choices are largely independent of each other and if one choice for one aspect influences choices that can be made for other aspects, this will be pointed out below.

[0028] Consequently, those with skill in the art will understand that the invention may be practiced without many of the details included in this detailed description. Conversely, somewell-known structures or functions may not be shown or described in detail, in order to avoid unnecessarily obscuring the relevant description of the various implementations.

[0029] The terminology used in the description presented below is intended to be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain specific implementations of the invention. To the extent that terms like first, second, upper, lower, left, right, near, far, and so on are used, they are intended to primarily distinguish features from each other, and not to define an absolute relationship, except where the context dictates otherwise. In particular, the terms top, upper, bottom, lower, horizontally, and vertically relate to the orientation of the illustrations in the drawings, and not to any absolute orientation of any device or part of a device according to the invention. Instead, a device according to the invention may have any orientation in use, and these terms are therefore not used in the claims, which substitutes terms like first and second.

[0030] Reference is first made to FIG. la which shows a view of an enclosure 100 in accordance with the principles of the invention. Some details are not included or visible in this view, but that does not mean this view is of an embodiment without those features. Instead, the view is deliberately simplified in order to explain certain features first.

[0031] The enclosure includes two main parts. The first part will be referred to as a bottom part 101 and the second part will be referred to as the top part 102.

[0032] The bottom part has an interior 103 which is configured to hold one or more components. The bottom part is of a circular shape and the outside of the sidewall 104 is provided with threads 105. The top part 102, which may also be referred to as the lid 102, has a corresponding sidewall 106 which is provided with threads on the inside. The threads on the inside of the sidewall 106 of the top part 102 match the threads 105 of the outside of the sidewall 104 of the bottom part 101 such that the two parts may be screwed onto each other.

[0033] FIG. lb shows the enclosure 100 from essentially the same perspective, but in a cross- sectional view. All the same details are visible, with the addition of the threads 107 of the upper part. Some details that are visible in FIG. 1 are not provided with reference numbers in order to avoid cluttering the drawing. They will be shown with reference numbers in other figures of the drawing and explained below.

[0034] Turning to FIG. 2, the same enclosure 100 is shown in a sectional side view and some additional details that are not included in FIG. 1 are also shown. In this view the enclosure is shown assembled, which means that the top part 102 has been screwed onto the bottom part 101. In this view it can be seen how the threads 105 of the bottom part 101 and the threads 107 of the top part 102 fit together. Additional features that are shown in this view include a projecting edge, or flange 108 (or rim) that is parallel to the sidewall 104 of the bottom part 101. This flange 108 is much lower than the sidewall 104 such that it encircles the lower part of the sidewall 104 and establishes a groove between the sidewall 104 and the flange 108. Thediameter of the bottom part 101 including the flange 108 is substantially the same as the diameter of the upper part 102. In this case, substantially does not mean that they are exactly the same and in principle their respective diameters may differ quite a lot. However, when the diameter of the two are substantially the same there will not be any edge around the side of the enclosure where the two differ in diameter. This may prevent accidental damage to the enclosure from foreign objects that might otherwise strike such an edge in a direction parallel to the sidewall and thus subject the enclosure to forces that might open it or dislocate it.

[0035] The upper part 102 has a corresponding projecting edge, or flange 109 at the bottom of its sidewall 106. (It should be kept in mind that terms like upper, lower, top, bottom, upward, and downward are intended to be interpreted relative to each other and based on the way respective parts and features are shown in the drawing, and that the enclosure may be oriented differently when in use.) This downward projecting flange 109 has an outer diameter smaller than the outer diameter of the sidewall 106 of the top part 102, and substantially corresponding to the inner diameter of the upward projecting flange 108 of the bottom part 101. However, except for the rim of the two flanges, where the two flanges 108, 109 meet and the upper part 109 enters inside the lower part 108, the diameter of the upper part is actually slightly larger than the diameter of the lower part 108. Thus, while the two parts 101, 102 will enter into engagement with each other easily, they will be pressed together when they are screwed together.

[0036] FIG. 3 is a view of the details of the two parts of the enclosure 100 when the bottom part 101 and the top part 102 are about to be assembled. This view focuses on details associated with the threads 105, 107 and the flanges 108, 109.

[0037] In this view, it can be observed that a slight tapering is provided on the inner surface of the flange 108 on the bottom part 101. This tapering ensures that while the upper, or inner, flange 109 enters nicely inside the outer flange 108, where the diameter of the inner flange 109 is smaller than then diameter of the outer flange 108, the two surfaces of the flanges 108, 109 are pressed together when the two parts of the enclosure are screwed together all the way. In particular, the outer diameter of the inner flange 109 may be slightly larger than the inner diameter of the outer flange 108, particularly where they meet at point 120 where the diameter of the outer flange 108 is at its smallest. This results in a slight deformation of the inner part, which will be pressed inwards where the two parts meet along the perimeter. This ensures continuous pressure of the two flanges against each other. This contributes to an enclosure that is watertight without the need for seals such as O-rings, press-in-place seals, sealing plates, or other static seals.

[0038] In the illustrated embodiment the diameter of the enclosure is approximately 90 mm and the height of the flanges (their overlapping parts) are between 5 mm and 10 mm. The outer diameter of the inner flange 109 along the rim may be approximately 0,5 mm larger than the diameter of the inner wall of the outer flange 108 at the bottom. This gives a tapering angle of the inner wall of the outer flange 108 of approximately 1,5° to 3° relative to the outersurface of the inner flange 109, which, of course, also may be tapering slightly. The tapering angle relative to the bottom surface of the lower part 101 can be anything between 1° and 15°, and in principle as little as 0.5° or as much as 40°. If the angle is large the relative change in diameter between the two surfaces will be higher for a given axial movement of the two enclosure parts, which means that there will be shorter travel from they touch each other with an initial contact and until they have reached maximum relative movement (and maximum pressure between them). Conversely, if the angle is small the two enclosure parts can move more in the axial direction relative to each other between initial contact and maximum pressure. Thus, the chosen angle becomes a design choice that can be based on the threading, the desired pressure between the two surfaces, the elasticity of the material, the relative tapering angle between the two surfaces (and the resulting difference in diameter), and other parameters a designer wants to take into consideration.

[0039] It should be understood that the view provided in FIG. 3 is not a different embodiment from that which is shown in the other figures. In the other figures the two flanges appear to have exactly the same shape because they are pressed together with the resulting temporary deformation of the inner flange.

[0040] Reference is now made to FIG. 4 which shows the bottom part 101 of the enclosure 100 with an electronic component or module inserted. The electronic module, which may be a printed circuit board or some other device, for example a sensor, a processor, a transponder, an RFID tag, or some combination of these and / or other components, is only just visible in this view because on top of the electronic module are three batteries 402 in a battery frame 403. The enclosure 100 may be shaped in a manner that facilitates insertion of the electronic component or module 401 without the need for tools, and with features that are designed to ensure that the electronic module 401 is held in place. For example, the enclosure may be provided with one or more features 404 such as notches, guides, slots, recesses, holes, taps, ridges, grooves, tabs, brackets, spacers, or pins that are configured to match the general shape of the electronic module 401 or corresponding in the electronic module 401 such as holes or notches configured to receive taps or tabs. It should be noted that the features 404 may be relatively small details on a larger general design, but also larger features that are part of the overall design of the enclosure 100 and the electronic module 401. Examples of smaller details include taps that fit into holes, while overall design features may simply be that the shape of the electronic module 401 fits into a recess or within internal sidewall with the same shape.

[0041] It will be realized that the features 404 designed to hold the electronic module in place may be part of the bottom part 101, the top part 102, or both parts may be provided with such features. Furthermore, different features 404 may be designed to prevent different movement of the electronic module 401. For example, if the bottom part 101 of the enclosure 100 is designed to receive the electronic module 401 it may be provided with features that prevent the electronic component 401 from rotating or moving horizontally. The top part 102 may be provided with features that prevent the electronic module 401 from moving vertically.In other embodiments both parts 101, 102 may be provided with features that prevent movement in more than one direction, and either part 101, 102 may be provided with such features regardless of whether the other part also has a feature preventing movement in the same direction. In some embodiments the battery or batteries 402 that provides power to the electronic module 401, which may include a frame or holder 403 for the battery, may serve also as one of the features that are designed to prevent movement of the electronic module.

[0042] FIG. 5 is another cross-sectional view of the enclosure 100 where the bottom part 101 and the top part 102 are assembled. Reference numerals to details that are visible in this figure but not discussed here are not included in the drawing in order to avoid cluttering the drawing unnecessarily even if they are described with reference to other figures. Inside the assembled enclosure 100 an electronic module 401 has been installed. The electronic module 401 rests on spacers or ridges 404a that ensure that the electronic module 401 does not rest directly on the inner surface of the bottom part 101 and therefore does not have to absorb any forces resulting from objects hitting the bottom of the enclosure 100. The bottom part 101 is also provided with locking members 404b which provide guiding of the electronic module 401 during insertion into the enclosure 100 and restrict movement in at least one direction subsequent to insertion. In some embodiments at least some locking members 404 may be elastic such that when the electronic module 401 is inserted into the bottom part 101 the locking members are deflected by the edges of the electronic module 401 until the electronic module 401 reaches its correct position, at which point the locking members 404b will at least partially return to their original position and press down on the upper surface of the electronic module 401 or a tapered edge thereof. The top part 102 is provided with a middle section 404c which is lower than the rest of the lid surface and configured to press down on the batteries 402, and the batteries, through the battery frame 403, press down on the electronic module 401. The battery frame 403 and the ridges 404a upon which the electronic module 401 rests and in contact with the electronic modules 401 at opposite sides such that any forces are transmitted through the electronic module 401 to be absorbed by the structure on the other side, i.e., either the ridge 404a or the battery frame 403. The lowered middle section 404c in combination with a certain elasticity of the material may ensure that the enclosure will exert a certain pressure onto the electronic module 401 and the horizontal surfaces of the bottom part 101 and the top part 102 will be pressed slightly apart by the batteries 402 and the battery frame 403. This elasticity will also be able to absorb forces the enclosure is exposed to, such as differences in pressure between the interior of the enclosure and the surrounding environment.

[0043] FIG. 6 is a top view of the bottom part 101 with the electronic module 401 and batteries 402 in battery frame 403 inserted. In this view it can be seen how some locking members 404b are configured to lock and hold the electronic module 401 in place, while other locking members 404d are configured to hold the battery frame 403.

[0044] FIG. 7 is a view that further illustrates a number of features mentioned above. It will again be understood that while certain details are not included in this view, these details may still be part of embodiments including the features of this drawing. This illustration again shows the enclosure 100 including a bottom part 101 and a top part 102. Without electronic module 401, battery 402 and battery frame 403, it is easier to see some other details of the enclosure 100. In this view it can be clearly seen that in this embodiment the ridge 404a constitutes a frame upon which the electronic module 401 may rest while being held in place by the locking members 404b at opposing sides. Locking members 404d for the battery frame 403 is shown on one side and these, too, may have corresponding members on the opposing side. This view also clearly shows how the upper part 102 has a central portion that is lowered in order to extend pressure upon the internal components while also providing a certain elasticity.

[0045] With respect to production methods and materials used when manufacturing an enclosure in accordance with the invention, there are several possibilities. First, the specific choice of material is not essential as long as the material chosen has the required properties. It is more important to reduce the number of different materials used, and preferable to manufacture the enclosure from only one material. Good choices include polypropylene (PP), polyethylene (PE), polyacrylamide (PA), polyoxymethylene (POM) and other thermoplastics with low coefficient of friction. The material should also have a certain flexibility in order to allow the compression or deformation of the rim around the inner flange 109 and also the lid 404c (or at least one of the parallel surfaces).

[0046] Using materials such as the ones mentioned above the enclosures 100 can be manufactured using injection molding. There should be no need for any subsequent processing or finishing.

Claims

CLAIMS1. Enclosure for an electronic module (401), comprising: a first part (101) with a first flat surface, a circular inner sidewall (104) with outside threads (105), a first flange (108) provided on the flat surface and encircling the circular sidewall (104), and provided with one or more features (404) configured to match the general shape of the electronic module (401), to match at least one corresponding feature in the electronic module (401), or to provide support for at least one surface of the electronic module (401); a second part (102) with a second flat surface, a circular outer sidewall (106) with inside threads (107) matching the outside threads (105) of the first part (101), a second flange (109) along the rim of the outer sidewall (106); wherein: the first part (101) and the second part (102) are made from a single material; and the second flange (109) is configured to fit between the inner sidewall (104) and the first flange (108) when the first part (101) and the second part (102) are screwed together by way of the outside threads (105) and the inside threads (107).

2. Enclosure according to claim 1, wherein the outer diameter of the second flange (109) is smaller than the inner diameter of the first flange (108) at least along a circle where the two flanges meet when the first part (101) and the second part (102) are screwed together, such that the second flange (109) will be deformed by being pressed inwards by the first flange (108).

3. Enclosure according to claim 1 or 2, further comprising a third part (403) configured to hold at least one battery (402) and to, when it is positioned inside the enclosure (100) and holding the at least one battery (402), direct forces to parts of the enclosure (100) that can absorb the forces without damage to the electronic component (401).

4. Enclosure according to claim 3, wherein forces are directed through the electronic module (401) and absorbed on one side by a feature (404a) in the first part (101) configured to provide support for at least one surface of the electronic module (401) and on an opposite side by the third part (403) configured to hold at least one battery (402), which in turn is configured to, directly or indirectly, direct forces to the second part (102).

5. Enclosure according to claim 4, wherein the third part (403) configured to hold at least one battery (402) is configured to direct forces to the second part (102) through the at least one battery (402).

6. Enclosure according to one of the previous claims, wherein the second flat surface, on the second part (102), is provided with at least a region (404c) which stretches towards thefirst flat surface, on the first part (101), providing a region that will subject pressure on components inside the enclosure (100) when such components have dimensions corresponding to the distance between the first surface and the second surface when the enclosure (100) is assembled.

7. Enclosure according to one of the previous claims, wherein at least one of the one or more features (404) configured to match the general shape of the electronic module (401), to match at least one corresponding feature in the electronic module (401), or to provide support for at least one surface of the electronic module (401) is configured as a locking member which will hold the electronic module (401) in place when it is inserted into the enclosure (100), and which is configured to absorb forces that are parallel to the first surface and the second surface.

8. Enclosure according to one of the previous claims, wherein the one or more features (404) configured to match the general shape of the electronic module (401), to match at least one corresponding feature in the electronic module (401), or to provide support for at least one surface of the electronic module (401) are configured to hold the electronic module (401) in place without additional fastening material such as screws, glue, and potting.

9. Enclosure according to one of the previous claims, where the one or more features (404) configured to match the general shape of the electronic module (401), to match at least one corresponding feature in the electronic module (401), or to provide support for at least one surface of the electronic module (401) are integral parts of the first part (101) created as part of the same process, and selected from the group consisting of: notches, guides, slots, recesses, taps, ridges, grooves, tabs, brackets, spacers, and pins.

10. Enclosure according to one of the previous claims, wherein the first part (101) and the second part (102) are manufactured using injection molding.

11. Enclosure according to one of the previous claims, wherein the first part (101) and the second part (103) are manufactured with a precision sufficient to ensure that the enclosure is watertight when assembled without addition of any gasket, seal, or additional component made from a material different from said single material.

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