Connecting element for shell, shell and assembling method of shell

Abstract

The invention relates to a connecting element for a shell, the shell and an assembling method of the shell. A connection element (21), for example for providing electromagnetic shielding of assembly halves (11, 12) of an electronic control unit (10). An element (21), for example formed as an elongated continuous piece from spring steel, comprises a first pair of elastic elements (22) for receiving a first half (12) of the housing and a second pair of elastic elements (24) for receiving a second half of the housing. The elements act as claws to position and secure the parts in an aligned configuration and eliminate any clearance / variation in the respective abutting edges.

Description

Technical Field

[0001] The present disclosure relates to a connection element for a housing, such as that required between adjacent parts of an electronic control unit (ECU) housing in order to provide electromagnetic compatibility (EMC). Background Art

[0002] An electronic control unit (ECU) typically includes a housing that is used to house various electronic devices therein, such as a processor chip on a printed circuit board (PCB) and associated wiring between the components / devices. The housing is typically assembled from two die-cast halves that must fit together and are used to provide electromagnetic compatibility (EMC) and electrostatic discharge (ESD) mitigation features to meet regulatory requirements.

[0003] The corresponding die-cast housing parts can be coupled together by complex and often expensive EMC / ESD protection solutions, such as washers made of polymers with embedded metal elements, as well as threaded fasteners for holding the parts together. A particular consideration is the need to compensate for the gap between the contact edges of the housing parts, which gap varies according to manufacturing tolerances. Summary of the invention

[0004] The present disclosure seeks to address the problem of, for example, fitting housing parts together while maintaining EMC / ESD protection.At a minimum, the disclosure herein provides an alternative option for connecting elements incorporated into an ECU housing.

[0005] According to a first aspect, a connecting element is provided. In an exemplary form, the present invention relates to a resiliently biased connecting element or spring clip, which includes: a first pair of resilient engaging elements or claws for receiving a first part to be connected; and a second pair of resilient connecting elements or claws for receiving a second part to be connected to the first part. The construction is such that the first pair of engaging elements receives and engages the first part of the housing by a first engaging force, and the second pair of engaging elements receives and engages the second part of the housing by a second engaging force. In one form, fixing the second part by the second pair of engaging elements causes the force of the first engaging force on the first part to increase. In this way, the engaging force determined by the resilient bias of each pair of elements connects the two parts, and the clamping force of the first pair of elements is naturally increased by engaging the second part into the second pair of elements. Similarly, the engaging force of the first pair that overcomes the resilient bias affects the second engaging force.

[0006] In an embodiment, the first and second pairs of jaws extend from opposite sides of the connecting element, for example from a common wall or platform forming the backbone of the element. In this way, if the first and second jaws are aligned, the first and second parts may also be aligned at the joint. However, alternative solutions are also possible, in which the jaws are offset to accommodate intentionally offset adjacent parts.

[0007] Typically, the trunk defines a longitudinal axis about which each pair of jaws pivots.

[0008] In an embodiment, one or both of the resilient claws / engagement features may include an opening profile that guides the first part and the second part to be received therein, respectively. In other words, the self-locating feature may cause the adjacent edges of the parts to align. In this way, the connecting element is in the form of an EMC spring that is able to self-locate and compensate for any variation in the gap found when connecting the two halves of the housing. Since the corresponding edges are hidden within the spring clips / engagement features, thereby allowing the gaps / variations to be accommodated, the EMC / ESD protection of the unit is improved and the limiting tolerances of the parts are smaller.

[0009] In an embodiment, the connecting element is formed by a sheet of material bent into a continuous shape. In an embodiment, the sheet is formed with a first claw of a first pair of resilient claws at a first edge, the sheet is bent forward to form a first claw of a second pair of resilient claws, the sheet is bent backward to form a platform / platform / bridge / trunk portion, the platform / platform / bridge / trunk portion is generally perpendicular to these claws so as to abut or approach the edge of at least one of the parts to be connected in use, the sheet is further bent backward to form a second claw of the second pair of resilient claws, the second claw is generally perpendicular to the platform, and the sheet is further bent forward to form a second claw of the first pair of resilient claws, the second claw corresponds to the second edge of the sheet and terminates at the second edge of the sheet. The first pair of claws may also include an outward bend to form a constriction area for engaging / gripping the first part to be connected.

[0010] Thus, the first and second jaws are generally aligned and have a pair of common upright walls separated by a trunk. The second pair of jaws may have a different depth than the first pair of jaws, such as a lesser depth, although the depth may be the same or greater. The structure may generally be described as an M-shape, although the center v-point of the M is flat. Alternatively, the profile may be described as a U-shaped portion in which the closed ends of the first pair of resilient elements (opposite the open ends that receive the first part of the housing and engage therewith) form an overall profile that includes the second pair of engaging elements.

[0011] In various embodiments, the overall profile is made of a sheet material (e.g., spring steel) formed into a continuous spring clip shape, the spring clip including first and second engagement features / resilient claws and a trunk / common wall therebetween for abutting or approaching the edge of the parts to be connected in use. The spring can be formed, for example, by multiple steps in a rolling mill, or stamped by multiple steps in a punching press, from initial bending and positioning of the sheet material until the final shape corresponding to M.

[0012] A second broad aspect of the present disclosure identifies a housing for an ECU. The housing may include a cover and a base part, each having upstanding walls configured to face each other at aligned edges and to form a protective cover within the housing. In addition, the respective upstanding walls of the cover and base parts are connected over at least a portion of the respective edges by a connecting element according to the first aspect. In an embodiment, the connecting element provides an engagement / retention function that is fixed between adjacent edges and optionally further fixed by a fastening element through aligned openings of the cover and base parts.

[0013] In this way, the housing is provided with an integral EMC / ESD protection at the seam / connection surfaces of the cover and base parts.The housing may comprise a plurality of connection elements received at respective edges of the upright walls.

[0014] According to a third aspect, an assembly method is provided. The housing according to the second aspect is assembled by: engaging a first pair of claws of at least one connecting element to an exposed edge of an upright wall of a cover or base part; aligning and engaging an exposed edge of an upright wall of the other of the cover or base parts with a second pair of claws of the connecting element; applying a force to open the second pair of claws, thereby connecting the edges of the cover and base parts. Prior to aligning and engaging the corresponding second claws with the second part, a plurality of connecting elements may be engaged at the edges by corresponding first claws. In a further step, a fastening element is engaged to secure the cover and base parts together, thereby clamping the connecting element between the edges.

[0015] In this way, the connecting element helps to provide a closed housing which, for example, in addition to environmental shielding, can also provide solid or liquid resistance at the joint. The assembly process eliminates the need to use gaskets on at least part of the edge of the connection, thereby reducing material consumption. The preferred form of non-plastically deformable (stainless) spring steel allows small cross-sections to be achieved, but the stresses can be very high.

[0016] According to the above, the problem of complex and often expensive EMC / ESD protection solutions for corresponding die-cast housing parts is solved by EMC longitudinal springs which allow closing of the opening line between the housing parts while reducing costs by relaxing tolerances.

[0017] The spring clip connection element described herein closes the longitudinal opening between the housing parts in an adaptive and self-positioning M-shaped configuration. It positions itself for attachment to two housing parts, thereby firmly connecting them and allowing the gap therebetween to change due to the protruding (claw) features that are clamped / engaged to clamp the portion of the upright wall beyond the edge from both sides. Even if the gap changes during assembly, after the initial compression, the spring joint is fixed so that opening does not occur.

[0018] The invention therefore relates to a standardized method for assembling electronic control units, thereby simplifying production and potentially avoiding additional costs for design changes. As mentioned above, this solution is a simple construction feature, but exemplifies many advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Illustrative embodiments will now be described with reference to the accompanying drawings, in which:

[0020] Figure 1 An overview of an electronic control unit ECU housing is shown in the form of two separate halves or parts;

[0021] Figure 2 shows an end view of the connecting element during assembly of the two parts;

[0022] Figure 3 A perspective view showing a connecting element of indefinite length; and

[0023] Figure 4 An overview of the housing of the electronic control unit ECU is shown in the assembled state. DETAILED DESCRIPTION

[0024] The following description provides exemplary embodiments and is accompanied by Figure 1 The present invention is intended to explain the principles of the present invention. However, the scope of the present invention is not intended to be limited to the precise details of the embodiments or to the precise conformity of all system features and / or method steps, as variations will be obvious to those skilled in the art and are considered to be covered by the specification. The terms used in this article for components should be given a broad interpretation, which also includes equivalent functions and features.

[0025] In some cases, several alternative terms (synonyms) for structural and system features have been provided, but these terms are not intended to be exhaustive. For the avoidance of doubt, any term separated by the " / " symbol generally refers to an alternative "or" expression in which the term can be used interchangeably. Descriptive terms should also be given the broadest interpretation; for example, the term "comprising" used in this specification means "at least partially composed of...", so that when interpreting each statement including the term "comprising" in this specification, there may also be features other than the features at the beginning of the term. Related terms are interpreted in the same way. Any directional terms, such as "vertical", "horizontal", "upward", "downward", "lateral", "up" and "down", are used for ease of explanation, usually with reference to the form shown in the figure, and are not intended to be ultimately limited if equivalent functions can be achieved with alternative sizes and / or directions. All directional terms are related to each other.

[0026] The description herein relates to embodiments with a specific combination of steps or features, however, it is contemplated that further combinations and cross-combinations of compatible steps or features between embodiments will be possible. In fact, separate features can function as inventions independently of other features, and are not necessarily required to be implemented as a complete combination.

[0027] It should be understood that the illustrated embodiments are for illustrative purposes only. In fact, the present invention can be applied to many different configurations, wherein the embodiments are straightforward to implement for those skilled in the art.

[0028] Figure 1 An overview of an electronic control unit (ECU) 10 of the type relevant to the present invention is shown. Such a unit may comprise a housing constructed from two parts, for example a cover part 11 and a base part 12, which cooperate to form a protective cover for internal electronic components (not shown). The upstanding side walls of each part 11 / 12 may comprise matching shaped / cut-out portions and generally have at least one set of corresponding edges to be abutted, for example 13, 16; 14, 17; 15, 18. The two halves may be secured together by suitable fastening means, for example screws, which are inserted and fastened into aligned openings 19, 20, for example located at a corner / projecting flange of the housing.

[0029] The housing parts may be made of metal, for example die cast or stamped (with upstanding side walls with appropriate flanges / ends), which results in variations in precision of dimensions / tolerances.

[0030] In this context, the invention facilitates a method of assembling an electronic control unit 10 as shown. In particular, at least one elongated connecting element 21 in the form of a resilient clip is provided, which serves as a means of engaging and connecting between edges 13, 14, 15 and edges 16, 17, 18, respectively.

[0031] Figure 2 An end view / section view is best shown, which shows the profile of the connecting element 21 relative to the parts 11 and 12 during assembly. In particular, the element 21 includes a first engagement feature, such as a pair of opposing claws 22, which can be engaged into the lower part 12 at a contact point / contraction point / engagement point 23 by a downward force or an upward force into the lower part 12. The claws 22 are resiliently biased to a narrower state, and the part 12 can be introduced into the widened opening in the claws 22 upstream of the constriction, thereby forcing them apart against the surface / point 23, as shown by the directional arrow F1.

[0032] A second engagement feature, such as a pair of opposing claws 24, is located on opposite sides of element 21, adjacent and projecting toward upper part 11. Respective claws 22 and 24 may be connected by a common platform / dock / backbone 25 that is relatively flat and provides a concave throat that is continuous with the upright walls of claws 24.

[0033] Figure 2 The assembled state (i) shows the upper part 11 before joining (the lower part 12 has been joined as described above), while Figure 2 State (ii) of FIG. 1 shows that part 11 has been forced downwardly with a force (F2) between claws 24, which is facilitated by the elasticity of element 21 and the guiding profile of the opening to claws 24. In other words, any misalignment between the edges of parts 11 and 12 is corrected by the opening itself. Part 11 is not necessarily forced to completely abut against platform 25 and may appear in state (ii) in its assembled form or in some variant thereof. During the engagement (i.e., forced apart) of the first pair of claws 22 in state (i), the second pair of claws 24 is pushed toward each other, i.e., tension is loaded into the second claw for subsequent engagement of the parts. In state (ii), part 11 forces the second claw 24 to separate against the tension. This also increases the force of the first pair of claws 22 (at point 23) acting on part 12. The outward force generated by part 11 is represented by the directional arrow F3.

[0034] For example, in Figure 2 Prior to state (i), the downward assembly force for engaging the first pair of claws 22 to the lower part 12 may be about 9N, thereby generating an outward force F1 of 12N at each claw 22 (retraction point 23).

[0035] exist Figure 2During the second state (ii) of the assembly, the 450N assembly force F2 can generate 620N in each direction (F3) at the second pair of claws 24. In addition, additional force is applied to the contraction point 23 of the first claw 22 by forcing the claws 24 apart by the introduction of the part 11. In the working example of (ii), the force in each direction F4 is increased to 40N.

[0036] Although in Figure 2 In state (ii), the upper part 11 and the lower part 12 of the housing are engaged and held together by the engagement / claw features of the connecting element 21 and the above-mentioned forces, however, conventional fasteners can still be used (through the aligned openings 19, 20) to secure the parts 11 and 12 together. In any case, it is obvious that any space / gap 26 between the parts 11, 12 is blocked by the connecting element (e.g., the wall of the claw 24) to reduce the ingress of dust, liquids and electromagnetic fields through the interface.

[0037] The structure shown ensures that the adjacent parts are aligned or urged into alignment. Alternative embodiments may have engagement features / pawls that are intentionally misaligned to accommodate intentional design features of the parts / housings. In this sense, "aligned" as used herein means guided into an intended relative position.

[0038] The electronics may be assembled into the housing in the normal manner prior to closing by the method described above. Figure 4 The overall assembly of the housing is shown, wherein the element 21 can be seen at the seam where it adjoins the side walls. The edges 13, 16; 14, 17; 15, 18 are effectively hidden within the element 21 from view.

[0039] The housing described herein may be constructed of known materials such as die cast metal. The resilient connecting element / clip of the present invention may be formed of spring steel sheet or equivalent material which maintains EMC properties for the ECU as a whole in order to meet regulatory standards.

[0040] By way of overview, the disclosure herein explains the function of a connecting element, such as providing electromagnetic shielding of the assembled halves of an electronic control unit. For example, an element formed into an elongated continuous piece from spring steel includes a first pair of resilient claws for receiving a first half of a housing and a second pair of resilient claws for receiving a second half of the housing. The claws position and secure the parts into an aligned configuration and eliminate any gaps / variations in the corresponding adjacent edges. The element is actually a clip formed from a spring steel sheet into a continuous, roughly M-shaped shape, wherein the legs of the M form a first pair of resilient claws and the V-shaped portion of the M forms a second pair of resilient claws. Although the tip of the V is preferably flattened to serve as a trunk portion along the longitudinal length of the clip.

Claims

1. A connecting element for connecting two parts of a housing, the connecting element include: a first pair of resilient engagement elements for receiving a first part of the housing; as well as a second pair of resilient engagement elements for receiving a second part of the housing to be coupled to the first part; wherein the first pair of resilient engagement elements are configured to receive a first part of the housing and engage with the first part with a first engagement force; wherein the second pair of resilient engagement elements are configured to receive a second part of the housing and engage with the second part with a second engagement force; Therein, fixing the second part by means of the second pair of elastic engagement elements results in an increase in the force of the first engagement force on the first part. 2 . The connecting element according to claim 1 , which is formed from an electromagnetic compatible material.

3. The connecting element according to claim 1 or 2, in, The first pair of elastic engagement elements and the second pair of elastic engagement elements extend from opposite directions of the common wall element for aligning the first part and the second part to be coupled.

4. The connecting element according to claim 1 or 2, in, The first pair of resilient engagement elements and the second pair of resilient engagement elements are formed as an integral profile that is elongated along a longitudinal axis about which each pair of resilient engagement elements pivots.

5. The connecting element according to claim 4, in, The closed end of the first pair of resilient engagement elements forms a U-shaped portion of the overall profile including the second pair of resilient engagement elements, the closed end being opposite to the open end receiving and engaging with the first part of the housing.

6. The connecting element according to claim 1 or 2, in, The openings leading to the pair of resilient engagement elements or both pairs of resilient engagement elements include guide features for facilitating positioning of the respective parts.

7. The connecting element according to claim 1 or 2, in, The second pair of elastic engagement elements has a depth less than or equal to that of the first pair of elastic engagement elements.

8. The connecting element according to claim 1 or 2, formed from spring steel.

9. A housing, the housing include: First part; Second part; wherein the first part and the second part each have an upright wall, the upright walls being configured to align with each other at corresponding edges to form an enclosed space within the housing; as well as At least one connecting element, the at least one connecting element being a connecting element according to any one of the preceding claims, for coupling respective upstanding walls of the first and second parts across at least a portion of the corresponding edges.

10. The housing according to claim 9, in, The first part and the second part are further secured together by at least one fastening element.

11. The housing according to claim 10, in, The fastening element is a screw extending through aligned openings of the first part and the second part.

12. The housing according to any one of claims 9 to 11, in, The first part and the second part are die cast or stamped metal sheets suitable for use as ECUs.

13. A method of assembling a housing according to any one of claims 9 to 12, the method The following steps are involved: a) engaging a first pair of resilient engagement elements of the at least one connecting element to an edge of an upright wall of any one of the parts with a first engagement force; b) aligning and engaging the edge of the upstanding wall of the other component with the second pair of resilient engagement elements of the connecting element; as well as c) applying a force to one or both of the first part and the second part in a direction toward each other, thereby forcing the second pair of elastic engagement elements to open and increase the first engagement force, thereby coupling an edge of the first part and an edge of the second part in electrical contact.

14. The method according to claim 13, in, In step a), a plurality of connecting elements are engaged at the edge via a corresponding first pair of elastic engagement elements.

15. The method according to claim 13 or 14, wherein include: d) engaging another fastening element to secure the first part and the second part together.

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