Contact element for electrically connecting printed circuit boards and method for assembling a printed circuit board arrangement

Abstract

A contact element for establishing electrical contact between a first and a second printed circuit board is provided. The contact element has a fastening region for fastening to the first printed circuit board and a plug section for a plug connection to the second printed circuit board. The plug section has at least two contact arms which are electrically conductively connected to one another. A method for assembling a printed circuit board arrangement is also provided.

Claims

1. A contact element for establishing an electrical contact between a first and a second printed circuit board comprising: a fastening region for fastening to the first printed circuit board; and a plug portion for a plug connection to the second printed circuit board, and wherein the plug portion has at least two contact arms, which are connected to one another in an electrically conductive manner, wherein the contact element is formed in one piece, wherein the contact element has an elongated form along a longitudinal axis, and wherein the at least two contacts of the contact element comprise a first contact arm, a second contact arm and a third contact arm spaced from one another along the longitudinal axis, wherein the second contact arm is located between the first contact arm and the third contact arm along the longitudinal axis, and the first contact arm and the third contact arm both protrude from the longitudinal axis in a transverse direction, which is perpendicular to the longitudinal axis, whereas the second contact arm protrudes from the longitudinal axis in the opposing direction that is opposite of the transverse direction.

2. The contact element as claimed in claim 1, wherein all of the contact arms are connected to one another in an electrically conductive manner so that the contact arms have the same electrical potential and form an individual contact.

3. The contact element as claimed in claim 1, wherein each of the contact arms has a bent form in cross-section.

4. The contact element as claimed in claim 1, wherein each of the contact arms has a tapering form in cross-section.

5. A contact element for establishing an electrical contact between a first and a second printed circuit board comprising: a fastening region for fastening to the first printed circuit board; and a plug portion for a plug connection to the second printed circuit board, wherein the plug portion has at least two contact arms, which are connected to one another in an electrically conductive manner, and wherein the fastening region has at least two fastening feet for fastening to the first printed circuit board, all of the at least two contact arms are arranged between the fastening feet in the direction of the longitudinal axis and the fastening feet are located further away from the longitudinal axis in the transverse direction than the contact arms extend in the transverse direction.

6. A contacting device comprising: a plurality of contact elements, each contact element including a fastening region having fastening feet for fastening to a first printed circuit board and a plug portion for a plug connection to a second printed circuit board, wherein the plug portion has at least two contact arms, which are connected to one another in an electrically conductive manner; and an insulating body, in which, for each contact element, at least one fastening opening is formed in each case, in which the respective contact element is held, wherein the at least two contact arms of each contact element project from an upper side of the insulating body and the fastening feet of the contact elements project from an underside of the insulating body, wherein the insulating body has at least two upwardly projecting adjusting pins on an upper side of the insulating body, wherein the adjusting pins are longer than the contact arms of the contact elements, and wherein each of the adjusting pins has a tapering end.

7. A printed circuit board arrangement comprising: at least one contact element including a fastening region and a plug portion, wherein the plug portion has at least two contact arms which are connected to one another in an electrically conductive manner; a first printed circuit board, to which the at least one contact element is fastened via the fastening region; and a second printed circuit board, which, for each of the at least one contact element, has at least one printed circuit board opening for inserting the at least two contact arms of the respective contact element, and wherein a contact socket is mounted at each printed circuit board opening, wherein the contact socket has a smaller opening than the printed circuit board opening and the opening of the contact socket is aligned with the printed circuit board opening.

8. The printed circuit board arrangement as claimed in claim 7, wherein a metallic coating is applied to each printed circuit board opening.

9. A printed circuit board arrangement comprising: at least one contact element including a fastening region and a plug portion, wherein the plug portion has at least two contact arms which are connected to one another in an electrically conductive manner; a first printed circuit board, to which the at least one contact element is fastened via the fastening region; and a second printed circuit board, which, for each of the at least one contact element, has at least one printed circuit board opening for inserting the at least two contact arms of the respective contact element, and wherein the printed circuit board opening or an associated contact socket forms a slot shape in the longitudinal direction of the at least one contact element and the contact arms of the at least one contact element contact opposing sides of the slot shape.

10. The printed circuit board arrangement as claimed in claim 9, wherein a width of the slot shape of the printed circuit board opening is smaller than a width of the contact element, which is defined by the at least two contact arms, so that, in the assembled state, the at least two contact arms are deformed by the slot shape of the printed circuit board opening.

11. A printed circuit board arrangement comprising: at least one contact element including a fastening region and a plug portion, wherein the plug portion has at least two contact arms which are connected to one another in an electrically conductive manner; a first printed circuit board, to which the at least one contact element is fastened via the fastening region; and a second printed circuit board, which, for each of the at least one contact element, has at least one printed circuit board opening for inserting the at least two contact arms of the respective contact element, wherein, to position fastening feet of the fastening region of the at least one contact element relative to the first printed circuit board, each of the at least one contact element has at least one supporting leg which stands on the first printed circuit board in the assembled state, and wherein the at least two contact arms are arranged such that the contact arms form a gap with respect to the first printed circuit board in the assembled state.

12. The printed circuit board arrangement as claimed in claim 11, wherein each contact element has a respective supporting leg between mutually adjacent ones of the at least two contact arms.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) Exemplary embodiments of the invention are illustrated in the drawings and will be explained in more detail below.

(2) FIG. 1 shows a perspective illustration of a detail of a printed circuit board arrangement according to an inventive exemplary embodiment.

(3) FIG. 2 shows a perspective illustration of a detail of the printed circuit board arrangement of FIG. 1 in an assembled state.

(4) FIG. 3 shows a perspective illustration of the contact element of the printed circuit board arrangement of FIG. 1.

(5) FIG. 4 shows a plan view of the contact element of FIG. 3.

(6) FIG. 5 shows a perspective illustration components of the printed circuit board arrangement of FIG. 1 in a non-assembled state.

(7) FIG. 6 shows a perspective illustration of components of the printed circuit board arrangement of FIG. 1 in a partially assembled state.

(8) FIG. 7 shows a perspective illustration of the printed circuit board arrangement of FIG. 1 in a partially assembled state.

(9) FIG. 8 shows a perspective illustration of the printed circuit board arrangement of FIG. 7 in an assembled state.

(10) FIG. 9 shows a perspective view of a contacting device according to an inventive exemplary embodiment.

(11) FIG. 10 shows a perspective illustration of the underside of the contacting device of FIG. 9.

(12) FIG. 11 shows a perspective illustration of a printed circuit board arrangement according to an inventive exemplary embodiment, comprising the contacting device of FIG. 9, in a partially assembled state.

(13) FIG. 12 shows a perspective illustration of the printed circuit board arrangement of FIG. 11 during assembly.

(14) FIG. 13 shows a perspective illustration of the printed circuit board arrangement of FIG. 11 in an assembled state.

(15) FIG. 14 shows a plan view of the printed circuit board arrangement of FIG. 13.

(16) FIG. 15 shows a perspective illustration of a second printed circuit board of a printed circuit board arrangement according to a further inventive exemplary embodiment.

(17) FIG. 16 shows a perspective illustration components of the printed circuit board arrangement of FIG. 15 in a non-assembled state.

(18) FIG. 17 shows a perspective illustration of the printed circuit board arrangement of FIG. 15 in a partially assembled state.

(19) FIG. 18 shows a perspective illustration of the printed circuit board arrangement of FIG. 17 in an assembled state.

(20) The figures may contain partially simplified, schematic illustrations. Identical elements are generally denoted by corresponding reference signs.

DETAILED DESCRIPTION

(21) A first exemplary embodiment of a printed circuit board arrangement 70 according to the invention is described with reference to FIGS. 1 and 2. The printed circuit board arrangement 70 has a first printed circuit board 30 and a second printed circuit board 40, and a contact element 1 for electrically connecting the two printed circuit boards 30 and 40. FIG. 1 shows a partially assembled state, in which the contact element 1 is fastened to the printed circuit board 30, but is still spaced from the second printed circuit board 40. FIG. 2, on the other hand, shows the fully assembled state, in which the contact element 1 makes contact with the second printed circuit board 40 and establishes an electrical connection.

(22) The two printed circuit boards 30 and 40 in the illustrated example are arranged parallel to one another but, more generally, can also be arranged at an angle of, for example, up to 30° to one another. The printed circuit boards 30 and 40 can be constituent parts of, in principle, any electronic devices and can belong for example to different motor components of a vehicle. A signal transmission and/or energy supply is intended to take place via the at least one electrical contact 1.

(23) The contact element 1 has a fastening region 20, via which the contact element 1 is fastened to the first printed circuit board 30. A plug portion 2 of the contact element 1 serves for the electrical contacting of the second printed circuit board 40, i.e., electrically conductive regions or components of the second printed circuit board 40. The plug region 2 is formed by a plurality of elongated contact arms 3, 4, 5. In the assembled state, the contact arms 3, 4, 5 extend in the z direction, which, in the present case, is also referred to as the vertical direction. The first printed circuit board 30, or its surface, extends in the xy plane, so that the contact arms 3, 4, 5 are perpendicular to the first printed circuit board 30 or, in more general terms, are at an angle of a maximum of 10° with respect to the surface normal of the first printed circuit board 30.

(24) The second printed circuit board 40 has at least one printed circuit board opening 41. In the illustrated example, this refers to an elongated hole in the second printed circuit board 40, which is provided with an electrically conductive coating 42. In the assembled state of FIG. 2, the contact arms 3, 4, 5 extend through the printed circuit board opening 41 and contact the coating 42. An electrical contact is therefore generated at the lateral surfaces of the contact arms 3, 4, 5 and not, for instance, at the tip or end face of the contact arms 3, 4, 5.

(25) As can be seen from FIG. 2, this construction offers high tolerances and good robustness with regard to vibrations in the z direction. An imprecise arrangement of the two printed circuit boards 30 and 40 with respect to one another in the z direction has no effect on the electrical contact owing to the length of the contact arms 3, 4, 5. There is no risk of a loss of contact in the event of vibrations or other disruptive influences in the z direction. In this case, tension does not build up between the two printed circuit boards 30 and 40 in the z direction so as to ensure the electrical contacting. This is in contrast to some conventional configurations, in which a contact element is clamped between two printed circuit boards and the contact element makes contact with the underside of the second printed circuit board, for example, which is facing the first printed circuit board.

(26) The contact element 1 of FIGS. 1 and 2 is shown on an enlarged scale in FIG. 3. It is formed in one piece, wherein, in principle, multi-part embodiments would also be possible. The contact arms 3, 4, 5 are connected to one another in an electrically conductive manner and have the same electrical potential in operation. The plurality of contact arms 3, 4, 5 thus act electrically as an individual contact. For reliable contacting with the second printed circuit board, the contact arms 3, 4, 5 are flexible or resilient relative to one another. This is achieved in that a connecting region 11 between the first and second contact arm 3, 4, and a connecting region 12 between the second and third contact arm 4, 5 is small compared to the length of the contact arms 3, 4, 5. By way of example, a z extent of the connecting regions 11 and 12 can be a maximum of 40% or a maximum of 30% of the z extent of the contact arms 3, 4, 5.

(27) The contact arms 3, 4, 5 are arranged offset or in succession in the x direction, whereby the contact element 1 has an elongated form in the x direction which, in the present case, is also referred to as the longitudinal axis of the contact element 1. The fastening region 20 for mounting on the first printed circuit board is formed by a plurality of fastening feet 25 and 26. In the illustrated example, two fastening feet 25 and 26 are present, which extend in the opposite direction (−z) to the contact arms 3, 4, 5, i.e., in the opposite direction to the z axis. A bent or angled region 23, 24 in each case leads from the contact arms 3, 4, 5 to the respective fastening foot 25, 26. The contact feet 25 and 26 thus lie further out in the y direction, i.e., they are further away from the contact arms 3, 4, 5 in the y direction. This arrangement is important for ensuring reliable positioning of the contact element 1 on the first printed circuit board 30. In this case, the contact feet 25 and 26 are located on opposite sides with respect to the longitudinal or x axis.

(28) The contact element 1 furthermore comprises bearing surfaces 18 and 19 on the contact feet 25 and 26. The bearing surfaces 18 and 19 are seated on the upper side of the first printed circuit board 30 and thus define how far the contact feet 25 and 26 project into or through corresponding cutouts in the first printed circuit board 30.

(29) The contact element 1 moreover has a plurality of supporting legs 21, 22, which are likewise seated on the upper side of the first printed circuit board 30. As a result of the supporting legs 21 and 22, is it ensured that the contact arms 3, 4, 5 are spaced from the surface of the first printed circuit board 30. This is particularly reliably achieved in that the supporting leg 21 is arranged between the first and second contact arm 3, 4 and the supporting leg 22 is arranged between the second and third contact arm 4, 5, as seen in the xy plane.

(30) The contact arms 3, 4, 5 each have a region 6, 7, 8 which tapers towards their plug-in end. Their insertion into the associated printed circuit board opening 41 of the second printed circuit board 40 can thus be facilitated. Moreover, the allowed tolerance with regard to imprecise positioning of the two printed circuit boards with respect to one another in the xy direction is thus increased. In particular, the outer contact arms 3 and 5 in the x direction each have a sloping surface, whereby the longitudinal or x extent of the contact arms 3, 4, 5 tapers towards the plug-in end. This sloping region can be omitted in the central contact arm 4 (or more generally in the central contact arms) or it can be smaller, whereby, for sufficient mechanical stability, the central contact arm 4 can be formed to be shorter in the x direction than the outer contact arms 3 and 5.

(31) FIG. 4 shows a plan view of the contact element 1, wherein it is inserted into a printed circuit board opening 41 of the second printed circuit board 40. As illustrated, the contact arms 3, 4, 5 are each spaced from one another by a gap 9 and 10 and contact the coating 42 of the printed circuit board opening 41. In this case, it is schematically shown that, in a non-assembled state, the y extent of the contact arms 3, 4, 5, as seen together, is greater than the y extent of the printed circuit board opening 41. As they are inserted into the printed circuit board opening 41, the contact arms 3, 4, 5 are therefore pressed together in the y direction. The first and third contact arm 3 and 5 project from a longitudinal or x axis of the contact element 1 in the positive y direction and thus contact one slot side of the printed circuit board opening 41, whilst the second contact arm 4 lying between them projects from the x axis of the contact element 1 in the negative y direction and thus makes contact with the opposite slot side. As they are inserted into the printed circuit board 41, the contact arms 3, 4, 5 are consequently bent in the negative y direction, whilst the contact arm 4 is deformed in the positive y direction. Particularly reliable contact in the y direction is thus achieved, even when vibrations or other disruptive forces act on the printed circuit board arrangement. In this case, it is important that adequate electrical contact is also realized if, for a short time, only one of the contact arms 3, 4, 5 contacts the coating in the event of jolting.

(32) FIG. 5 shows the assembly of a plurality of contact elements 1 on the first printed circuit board 30. The first printed circuit board 30 comprises cutouts 31 and 32 for the fastening feet 25, 26 of the respective contact elements 1. The fastening feet 25, 26 are inserted into the cutouts 31, 32 and are held therein by press fit or are soldered therein. The cutouts 31 and 32 can be continuous holes. This can be particularly advantageous for soldering, for which a length of the fastening feet 25, 26 from the bearing surfaces 18, 19 (see FIG. 1) can be dimensioned such that the fastening feet 25, 26 project completely through the first printed circuit board 30.

(33) FIG. 6 shows, in a perspective plan view, a state in which the plurality of contact elements 1 are assembled on the first printed circuit board 30. The connection to the second printed circuit board 40 then takes place, as shown schematically in FIGS. 7 and 8. For each contact element 1, the second printed circuit board 40 has one printed circuit board opening 41 in each case, at which a respective electrical contact 1 is to be established. As illustrated in FIG. 8, the contact arms 3, 4, 5 of the contact elements 1 project through the respective printed circuit board openings 41 in the fully assembled state.

(34) In this exemplary embodiment of FIGS. 6 to 8, each contact element 1 is individually seated and assembled on the first printed circuit board 30. In order to reduce this assembly effort, in the exemplary embodiment of FIGS. 9 to 14, an additional insulating body 50 is used, which holds a plurality of contact elements 1. FIG. 9 shows the insulating body 50 in a perspective view, whilst FIG. 10 shows the insulating body 50 in a perspective view from below. The insulating body 50 has a plurality of fastening openings 55, into which the contact elements 1 are inserted or clamped. In the present case, the module comprising the insulating body 50 and a plurality of contact elements 1 is referred to as contacting device 60. The contacting device 60 is assembled as a whole on the first printed circuit board 30. To this end, the insulating body 50 comprises holding elements 53 (FIG. 10) on its underside, which are inserted or pressed into corresponding cutouts in the first printed circuit board 30. The insulating body 50 moreover has a plurality of projections 54 on its underside, which bear on the surface of the first printed circuit board 30 and thus ensure a precise z position of the contact elements 1 relative to the first printed circuit board 30. The fastening feet 25, 26 and the bearing surfaces 18, 19 and supporting legs 21, 22 shown in more detail in FIG. 3 protrude from the underside of the insulating body 50 so that they can contact the first printed circuit board 30 when the insulating body 50 is seated on the first printed circuit board 30.

(35) FIGS. 11 to 13 show the assembly procedure of the printed circuit board arrangement 70. In FIG. 11, the insulating body 50 is already connected to the first printed circuit board 30 and has a plurality of adjusting pins 51 which project further upwards from the printed circuit board 30 than the contact elements 1. The adjusting pins 51 are now inserted into corresponding openings 43 in the second printed circuit board 40, as shown in FIG. 12. Since the adjusting pins 51 each have a tapered end 52, correct xy alignment between the second printed circuit board 40 and the rest of the construction is facilitated. The second printed circuit board 40 is now moved further towards the first printed circuit board 30 until the contact arms 3, 4, 5 of the contact elements 1 project through the corresponding printed circuit board openings 41, as illustrated in FIG. 13. The adjusting pins 51 can optionally also have a holding geometry by means of which a movement of the second printed circuit board 40 towards the first printed circuit board 30 is restricted (not shown).

(36) It is essentially also possible to connect more than two printed circuit boards in this way. A further printed circuit board, which is formed similarly to the second printed circuit board, can therefore be seated on the adjusting pins (not illustrated). The contact arms of the contact elements then project through the printed circuit board openings from the second and the further printed circuit board. Information or energy transmission can then optionally take place from one printed circuit board to one or more other printed circuit boards.

(37) A plan view of the printed circuit board arrangement 70 of FIG. 13 is shown in FIG. 14. In the illustrated example, eight mutually independent electrical connections between the printed circuit boards 30, 40 are provided by eight contact elements 1.

(38) Whilst, in the previously described exemplary embodiments, a metallic coating 42 is present at the printed circuit board openings 41, this can be omitted in the exemplary embodiment of FIGS. 15 to 18. FIG. 15 shows the second printed circuit board 40 in a perspective view. Its printed circuit board openings 41 are not provided with a conductive coating here; instead, a respective contact socket 45 is arranged at each printed circuit board opening 41. An electrical connection is then established via contact between the contact arms 3, 4, 5 of a contact element 1 and the associated contact socket 45.

(39) FIG. 16 primarily illustrates the assembly of the contact sockets 45 on the second printed circuit board 40. The contact sockets 45 can each comprise pins, which are inserted into corresponding holding openings of the second printed circuit board 40 in order to ensure that the contact sockets 45 are held in place.

(40) The first printed circuit board 30 with the insulating body 50 assembled thereon and the contact elements 1 can be formed in the manner of the previous exemplary embodiment. FIG. 17 shows that the contact sockets 45 are arranged on the side of the second printed circuit board 40 which is facing the first printed circuit board 30. In the assembled state, which is shown in FIG. 18, the contact elements 1 project through the contact sockets 45 and the printed circuit board openings 41, wherein they contact the contact sockets 45 and not, for instance, walls of the printed circuit board opening 41. As a result of the contact sockets 45, when compared to metallic coatings, a greater number of plug-in procedures can be enabled without resulting in significant wear.

(41) As a result of the different embodiments described, reliable electrical contact between at least two printed circuit boards can be ensured even when vibrations or other disruptive forces occur in different directions. At the same time, there is no, or barely any, tension between the printed circuit boards which could cause deflections or other damage to the printed circuit boards in the long term. Apart from a certain pressing together of the contact arms in the y direction, there is also no, or barely any, tension on the contact elements, which means that the wear is low and the durability is correspondingly high.

(42) Aspects of various embodiments described above can be combined to provide further embodiments.

(43) In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled.