Component with a flexible contact film

Abstract

Component (10) with a flexible contact foil (20), wherein - the contact foil (20) is electrically connectable to one or more contact surfaces (16) of the component (10), - the flexible contact foil (20) has two recesses (21, 22) which are arranged corresponding to respective projections (11, 12) of the component (10), wherein the respective projections (11, 12) protrude into the two recesses (21, 22) of the contact foil (20) for at least temporarily fixing the contact foil (20) to the component (10), characterized in that - a first of the recesses (21, 22) of the contact foil (20) is circular and a second of the recesses (21, 22) is designed as a drop-shaped elongated hole, the elongated hole opening in a funnel shape in the direction of the first recess (21), - the first and second recesses (22) are spaced apart from one another such that -- a first (11) of the projections (11, 12) projecting into the first recess (21) is arranged concentrically to an edge of the first recess (21) and bears along the entire edge of the first recess (21), and -- a second (12) of the projections (11, 12) bears against an edge portion (23) of an edge of the second recess (22) facing away from the first recess (21) in such a way that there is tension in the flexible contact film (20) in a region between the first (21) and the second recess (22).

Description

[0001] The invention relates to a component with a flexible contact foil, wherein the contact foil is electrically connectable to one or more contact surfaces of the component. The flexible contact foil has two recesses arranged corresponding to respective projections of the component. The respective projections protrude into the two recesses of the contact foil to at least temporarily fix the contact foil to the component.

[0002] The two recesses in the flexible contact foil and the associated protrusions serve to pre-fix the flexible contact foil to the component. In the area between the two recesses, the flexible contact foil must be positioned relative to the component without a so-called zero gap. This means that the flexible contact foil should be in contact with the component across the entire area between the two recesses and should not exhibit any partial bulges or bumps. Only in this way is a correct connection between the flexible contact foil and the component possible during subsequent processing.

[0003] The aim is therefore to dimension the component and flexible contact foil in such a way that the flexible contact foil is subjected to tension in the area between the two cutouts when it is connected to the component. At the same time, the cutouts and the respective projections should ensure correct positioning of the flexible contact foil on the component. This is relevant if the component is provided with one or more contact surfaces, preferably in the area between the two cutouts or projections, which are to be contacted by the conductor structure of the flexible contact foil. The electrical connection between the contact surfaces of the component and the contact surfaces of the conductor structure is usually created using a welding process, e.g. laser welding.

[0004] If the two recesses are formed by two (circular) holes, the flexible contact foil can be (pre-)attached to the component very well. The disadvantage of this is that slight bulges or waves can occur in the flexible contact foil due to spacing differences caused by tolerances in the manufacturing of the component and the contact foil. In particular, bulges or waves can form in the area between the recesses or projections, complicating the subsequent lamination and / or welding process.

[0005] DE 10 2004 054 985 A1 discloses an arrangement comprising an electronic component and a flexible circuit carrier, in which the circuit carrier and the component are connected to one another via locking elements. For this purpose, a locking hook is provided on the outer surface and protrudes from the outer surface, which interacts with a locking recess to connect the component to the circuit carrier. Furthermore, locking pins protruding from the outer surface are provided, which interact with second, circular locking recesses in the circuit carrier. To assemble the arrangement, the component is first moved towards the circuit carrier. The locking hook is pushed through the first locking recess. The locking pins of the component are offset from the second locking recesses on the outer side of the circuit carrier facing the component.By sliding the component laterally relative to the circuit carrier, the locking hook engages behind the edge of the first locking recess. Furthermore, the locking pins align with the second locking recesses, allowing the locking pins to be pushed through them. A disadvantage of the described arrangement is that, due to spacing differences caused by tolerances during the manufacturing of the component and the flexible circuit board, slight bumps or waves can occur between the locking connections. This also complicates the subsequent process of establishing the electrical connection between the component and the flexible circuit board.

[0006] Furthermore, DE 86 25 853 U1 discloses a device with a holder for receiving a detachable electrical component. The component, which is provided with a spring-loaded fastening element and positioning pins, is attached to a support element made of flat sheet metal with punched-out portions. The fastening element is inserted through a recess until the end face of the housing rests against the surface of the support element. The housing is then moved so that the positioning pins align with circular recesses in the sheet metal. By moving the component relative to the support element, the fastening element engages the sheet metal. However, the procedure described therein is not transferable to a component with a flexible contact foil, where it is difficult to avoid ejections or waves in the flexible contact foil.

[0007] US 2005 / 0 085 104 A1 discloses an arrangement for connecting the terminals of an electronic component to electrical contacts formed on a printed circuit board. An at least partially flexible conductor carrier with a plurality of connections establishes an electrical connection between the terminals of the electronic component and the electrical contacts of the printed circuit board, such that a portion of the conductor carrier connected to the printed circuit board is arranged on an end face of the printed circuit board and extends perpendicularly with respect to the top and bottom surfaces of the printed circuit board.

[0008] US 5 981 870 A discloses a flexible printed circuit board connection that is equipped with strain relief options.

[0009] DE 31 07 552 A1 discloses a device for mechanically securing an electrical connection between two objects. An integrally formed projection projecting from a surface of the first object in a first direction cooperates with an integral portion of the second object that is relatively movable toward the surface in a second direction, generally opposite to the first direction, to position the cooperating portion proximate the projection. The projection or the cooperating portion are formed at least partially from resilient material.

[0010] US Pat. No. 3,838,203 A discloses a substrate and an electrical connection fixture in the form of a connector strip. These are designed so that the strip can be pressed precisely into position on the substrate to establish a circuit path thereon without deforming the strip.

[0011] It is therefore an object of the present invention to provide a component with a flexible contact foil which avoids the above-mentioned disadvantages.

[0012] This object is achieved by the features of patent claim 1. Advantageous embodiments are set out in the dependent patent claims.

[0013] In a component according to the invention with a flexible contact foil, the contact foil is electrically connectable, in particular connected, to one or more contact surfaces of the component. The flexible contact foil has two recesses arranged to correspond to respective projections of the component, wherein the respective projections protrude into the two recesses of the contact foil for at least temporarily fixing the contact foil to the component. A first of the recesses in the contact foil is circular, and a second of the recesses is designed as a drop-shaped elongated hole, wherein the elongated hole opens in a funnel shape toward the first recess.The first and second recesses are spaced apart from one another in such a way that a first of the projections projecting into the first recess is arranged concentrically to an edge of the first recess and bears along the entire edge of the first recess, and a second of the projections bears against an edge portion of an edge of the second recess facing away from the first recess in such a way that there is tension in the flexible contact film in a region between the first and second recesses.

[0014] By virtue of the inventive configuration of the component with a flexible contact foil, on the one hand, tolerances can be compensated for by the resulting distance differences between the protrusions and the recesses. On the other hand, by means of the second recess designed as a slot, precise positioning of the flexible contact foil on the component can be ensured. The fixation is effected via the circular first recess, while the second recess, designed as a slot, aligns the flexible contact foil on the component. At the same time, by positioning the protrusions relative to the two recesses, a slight tension can be generated in the flexible contact foil, thereby ensuring the required zero gap, particularly in the area between the two recesses or protrusions.As a result, the subsequent processes of lamination and / or welding can be carried out with high precision, thereby increasing the reliability of the component according to the invention.

[0015] According to an expedient embodiment, the edge section facing away from the first recess extends in the axial direction of the second projection to enlarge a contact surface. The extension or folding of the edge section is brought about when the flexible contact foil and the component are connected. Due to the dimensioning of the distance between the two recesses and the respectively associated projections, the edge section of the flexible contact foil is "carried along". In order to be able to slide the flexible contact foil with its recesses over the two projections, the resistance during the deformation of the flexible contact foil in the region of the edge section must be overcome. This then brings about the intended tension in the region between the two recesses or the two projections.

[0016] An axis of symmetry of the elongated hole lies on a straight line connecting a center of the first recess with the centers of the circular arc sections of the second recess. This allows for compensation of a component tolerance.

[0017] In a further expedient embodiment, the arrangement of the two recesses and the respective projections is such that the center of the circular-arc-shaped edge section of the second recess facing away from the first recess coincides with the center of the associated second projection. Such an arrangement should exist in particular in a so-called zero position, i.e. in a state in which the recesses and the associated projections are in their desired position. In such a situation, maximum accuracy of the relative arrangement of the flexible contact foil to the component is ensured. Furthermore, maximum tolerance compensation can be achieved.

[0018] A further embodiment provides that the radius of the circular arc-shaped section of the second recess facing away from the first recess is smaller by a predetermined amount than the radius of the associated second projection. This achieves the desired enlargement of the contact surface, since the edge section is forced in the axial direction of the second projection, thus creating the fold.

[0019] According to the invention, the elongated hole is drop-shaped, opening in a funnel shape towards the first recess. The drop-shaped elongated hole ensures more reliable positioning than an elongated hole with long, parallel legs. The drop-shaped elongated hole ensures alignment and ensures slight tension in the flexible contact foil, even within a specified tolerance range. Even in an unfavorable tolerance case, the flexible contact foil is thus installed with slight tension. The worst tolerance case occurs when the recesses in the flexible contact foil are at a maximum permissible distance from one another and, at the same time, the projections of the component are at a minimum distance from one another.

[0020] According to a further advantageous embodiment, the radius of the first recess is smaller by a predetermined amount than the radius of the associated first projection. This ensures a good fixation of the flexible contact foil to the component.

[0021] According to a further embodiment, the contact surfaces to be electrically contacted are arranged in the region between the first and second recesses. Due to the inventive relative arrangement of the recesses and the projections to one another, it is ensured that tension is present in the flexible contact foil in this region, so that no bulges can occur in the region of the contact surfaces that would prevent or impair contact.

[0022] Similarly, the contact foil can be fully bonded to the component in the area between the first and second recesses. This ensures that the bond is fully bonded in this area due to the tension in the flexible contact foil.

[0023] A further embodiment provides that the contact surfaces of the component in the area between the first and the second recess are welded over the entire surface to the conductor structure of the contact surfaces.

[0024] The invention is explained in more detail below with reference to the figures. They show: Fig. 1 a plan view of a component according to the invention with a flexible contact foil attached thereto, and Fig. 2A to 2C each show a plan view, a side view and a perspective view of the steps for producing a component according to the invention with a flexible contact foil.

[0025] Fig. 1 shows a top view of a component 10 according to the invention with a flexible contact foil 20 attached thereto. In the top view, the component 10 has, for example, an approximately circular cross-section and can represent a sensor, a connector, or the like. On the side of the component 10 facing the viewer, one or more contact surfaces (not visible in this view) can be arranged, which can be contacted via the flexible contact foil 20.

[0026] The flexible contact foil 20 is a so-called flex foil, which has an elastic, flexible plastic carrier on which a conductor structure can be formed. The conductor structure enables the creation of electrical connections between respective contact surfaces of one or more components 10. Fig. 1, the conductor structure is located at least on one main surface of the contact foil 20 facing the component 10.

[0027] To enable reliable contacting or fixing, the flexible contact foil 20 must first be correctly aligned with the component 10. For this purpose, the contact foil 20 has a first, circular recess 21 and a second recess 22, which is drop-shaped in the exemplary embodiment. Corresponding to the first and second recesses 21, 22, corresponding projections 11, 12, each with a circular cross-section, are formed on the component 10 in this exemplary embodiment. A radius r11 of the projection 11 is slightly larger than a radius r21 of the first recess 21. As a result, the flexible contact foil 20 is turned inside out perpendicular to an axis of the projection 11 when connected to the component 10. The flexible contact foil 20 is deformed in the region of its edge and ensures a play-free fit relative to the projection 11.

[0028] The drop-shaped second recess 22 opens in a funnel shape toward the first recess 21, with an axis of symmetry of the drop-shaped recess 22 lying on a straight line connecting a center 27 of the first recess 21 with the centers 28, 29 of circular-arc sections 23 and 24 of the second recess 22. The circular-arc section 23 has a radius r23 that is slightly smaller than a radius r12 of the second projection 12. A radius r24 of the circular-arc section 24 facing the first recess 21, however, is larger than the radius r12 of the second projection 12 due to the drop shape of the second recess.

[0029] The design of the second recess 22 as an elongated hole creates a length compensation that can compensate for a tolerance in the distance between the two projections 11, 12 as well as the distance between the two recesses 21, 22. Furthermore, the drop-shaped recess 22 ensures more precise positioning of the flexible contact film 20 relative to the component 10. The second, drop-shaped recess 22 takes over the alignment, with a slight tension being achieved in the area between them due to the spacing of the first and second recesses 21, 22 relative to the first and second projections 11, 12. The spacing of the first and second recesses 21, 22 is such that the first projection 11 projecting into the first recess is arranged concentrically to the edge of the first recess 21, so that the projection 11 bears along the entire edge of the first recess.The second projection 12 rests against the edge portion 23 of the edge of the second recess facing away from the first recess 21.

[0030] Due to the dimensioning described above, it can be ensured that there is tension along the straight line that coincides with the axis of symmetry 26, whereby the flexible contact foil exhibits no bulges or waves in this area. Furthermore, a recess formed between the edge section 24 and the projection 12 can, in an unfavorable case, smooth out any bulge or wave that may arise in the area between the two recesses 21, 22. This provides an arrangement of contact foil 20 and component 10 that has a so-called zero gap. This means that the flexible contact foil 20 rests against the component 10 over its entire surface.

[0031] The Fig. 2A to 2C show the attachment of the flexible contact foil 20 to the component 10 in a top view, a side view and a perspective view, respectively.

[0032] In Fig. 2A shows the situation in which the flexible contact foil 20 is aligned with the component 10, so that the recesses 21, 22 are positioned corresponding to the projections 11, 12. In the side view of the Fig. 2A further shows that on a surface of the component 10 facing the contact foil 20, in the area between the projections 11 and 12, three contact surfaces 16 are arranged, for example, which are to be contacted via the conductor structure (not shown) provided on the contact foil 20.

[0033] Fig. Figure 2B shows the situation in which the projections 11, 12 partially penetrate the corresponding recesses 21, 22 of the flexible contact foil 20. It is particularly evident from the top view and the perspective view that the edge of the recess 21 and the edge section 23 of the recess 22 are folded over due to the dimensioning of the projections and recesses described above. This mechanical deformation creates tension in the area between the recesses or projections 11, 12.

[0034] Fig. Figure 2C shows the situation in which the flexible contact foil 20 is completely applied to the component 10. It can be seen that the edge portion 25 is deformed and extends in the axial direction of the projection 12.

[0035] With correct dimensioning of the spacing between the recesses 21, 22 and the projections 11, 12, the inverted edge section 23 is arranged mirror-symmetrically with respect to the axis of symmetry. This results in a maximum length over which the projection 12 is in contact with the edge of the second recess 22. This creates maximum and optimized tension in the area between the projections 11, 12 and the recesses 21, 22, ensuring that the flexible contact foil 20 rests against the component 10 over its entire surface.

[0036] The advantages of the inventive procedure can be summarized as follows: The provision of a circular recess and an elongated hole as a further recess enable the greatest possible tolerance when joining a flexible contact foil to a component 10. Exact positioning of the flexible contact foil is made possible, whereby bulges and wave formation of the flexible contact foil in the area between the two recesses or the two projections are avoided.

[0037] Contrary to the description and illustration in the exemplary embodiment, the projections 11, 12 do not have to be an integral part of the component 10, but can also be formed, for example, on a machining tool. The projections can then be inserted into position markers (e.g., in the form of holes) of the component for the purpose of securing the flexible contact foil. After securing and / or electrical contacting, the projections can then be removed again.

Claims

[1] Component (10) with a flexible contact foil (20), wherein - the contact foil (20) is electrically connectable to one or more contact surfaces (16) of the component (10), - the flexible contact foil (20) has two recesses (21, 22) which are arranged corresponding to respective projections (11, 12) of the component (10), wherein the respective projections (11, 12) protrude into the two recesses (21, 22) of the contact foil (20) for at least temporarily fixing the contact foil (20) to the component (10), characterized by , that - a first of the recesses (21, 22) of the contact foil (20) is circular and a second of the recesses (21, 22) is designed as a drop-shaped elongated hole, the elongated hole opening in a funnel shape in the direction of the first recess (21), - the first and second recesses (22) are spaced apart from each other such that -- a first (11) of the projections (11, 12) projecting into the first recess (21) is arranged concentrically to an edge of the first recess (21) and bears along the entire edge of the first recess (21), and -- a second (12) of the projections (11, 12) bears against an edge portion (23) of an edge of the second recess (22) facing away from the first recess (21) in such a way that there is tension in the flexible contact film (20) in a region between the first (21) and the second recess (22). [2] Component (10) according to claim 1, characterized by that the edge portion (23) facing away from the first recess (21) extends in the axial direction of the second projection (12) to enlarge a contact surface. [3] Component (10) according to one of the preceding claims, characterized bythat an axis of symmetry of the elongated hole lies on a straight line connecting a center of the first recess (21) with centers of circular arc-shaped sections of the second recess (22). [4] Component (10) according to claim 3, characterized by that the arrangement of the two recesses (21, 22) and the respective projections (11, 12) is such that the center of the circular arc-shaped section of the second recess (22) facing away from the first recess (21) coincides with a center of the associated second projection (12). [5] Component (10) according to claim 4, characterized by that a radius of the circular arc-shaped section of the second recess (22) facing away from the first recess (21) is smaller by a predetermined amount than a radius of the associated second projection (12). [6] Component (10) according to one of the preceding claims, characterized bythat a radius of the first recess (21) is smaller by a predetermined amount than a radius of the associated first projection (11). [7] Component (10) according to one of the preceding claims, characterized by that the contact surfaces (16) to be electrically contacted are arranged in the region between the first (21) and the second recess (22). [8] Component (10) according to one of the preceding claims, characterized by that the contact foil (20) is fully bonded to the component (10) in the area between the first (21) and the second recess (22). [9] Component (10) according to one of the preceding claims, characterized by that the contact surfaces (16) of the component (10) in the region between the first (21) and the second recess (22) are welded over the entire surface to a conductor structure of the contact foil (20).

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