ELECTRICALLY CONDUCTIVE CONNECTION OF CIRCUIT BOARDS

Description

[0001] The invention relates to an electrically conductive contact connection between a first and a second printed circuit board according to the preamble of claim 1.

[0002] Furthermore, the invention relates to a method for producing an electrically conductive contact connection between a first circuit board and a second circuit board according to the preamble of claim 6.

[0003] Electrically conductive contact connections between components, such as circuit boards, are known from the prior art. DE 10 2011 119 842 B4 discloses an electrical connecting element comprising several soldered pins that can be pressed into a hole in a circuit board. According to US Pat. No. 3,980,367 A, several circuit boards are connected to one another using a connector surrounded by molten solder.

[0004] EP 0 664 576 A2 and DE 10 2018 10 557 A1 describe printed circuit board arrangements in which a fixed distance between rigid printed circuit boards is specified by connection pins.

[0005] JP H08 213068 A discloses a plug connection between a printed circuit board and a flat electrical connection cable. JP H08 213068 A and DE 10 2014 011704 A1 each disclose a contact connection according to the preamble of claim 1.

[0006] Furthermore, it is known, for example, to connect two printed circuit boards, in particular a rigid and a flexible printed circuit board, via so-called connector strips and printed circuit board sockets, pin or socket strips, which are mounted on the printed circuit boards. The object of the present invention is to provide an electrically conductive contact connection that is more cost-effective and can be produced with less effort than the prior art, and a method for producing the electrically conductive contact connection.According to the invention, it is proposed that the connecting pin comprises a second section which is partially arranged in a second opening formed in the second printed circuit board, wherein the second section of the connecting pin comprises a holding element, and the holding element engages over the second printed circuit board on a side facing away from the first printed circuit board in such a way that a positive connection is formed between the first and the second printed circuit board.

[0007] The contact connection according to the invention can be manufactured without requiring any further soldering. Compared to a plug-in connection, the contact connection according to the invention requires little material expenditure.

[0008] According to the invention, the retaining element comprises a resilient element or is designed as a resilient element. The resilient element can, for example, be compressed upon insertion of the second section into the second opening and subsequently, when a part of the second section protrudes from the second opening on a side facing away from the first circuit board, spring back. This then forms the retaining element, which engages over the second circuit board on the side facing away from the first circuit board in such a way that a positive connection is formed between the first and second circuit boards.

[0009] According to an embodiment not falling within the scope of the claims, it may prove advantageous if the retaining element is formed by a plastic forming process. The second section of the terminal pin is plastically deformable at least in a section protruding through the second opening of the second circuit board and beyond the second circuit board. The retaining element is then formed, for example, in a forming process, in particular a bending process or a riveting process, in particular as a rivet head.

[0010] It may also prove advantageous if the first section of the terminal pin is solid or flexible. If the first section is solid, it is a non-compressible press-in contact. In this case, the first circuit board is deformed in the area of ​​the first opening. If the first section is flexible, the terminal pin is compressed in the area of ​​the first section upon insertion into the first opening through contact with the first opening, thereby creating a preload.

[0011] Advantageously, an inner wall of the first opening of the first circuit board and / or an inner wall of the second opening of the second circuit board comprises an electrically conductive material. The inner wall of the first opening of the first circuit board and / or the inner wall of the second opening of the second circuit board are electrically connected to conductor tracks of the first or second circuit board. The connecting pin contacts the inner walls of the first and / or second opening at least partially, preferably over their entire circumference, thereby forming an electrically conductive connection.

[0012] Advantageously, the terminal pin is formed at least partially from an electrically conductive material. The terminal pin is made, for example, from metal and / or an alloy and / or partially from plastic in combination with an electrically conductive material.

[0013] It may prove advantageous if the first and second openings have different diameters. This can be particularly advantageous when establishing the electrically conductive contact connection. For example, the first section of the terminal pin can be assigned to the first opening, and thus to the first circuit board, and the second section of the terminal pin can be assigned to the second opening, and thus to the second circuit board.

[0014] According to the invention, the first circuit board is a rigid circuit board and the second circuit board is a flexible circuit board. The first circuit board comprises, for example, a non-conductive carrier material, a glass fiber mat impregnated with epoxy resin, also known under the material identifier FR4. The second circuit board is, for example, a particularly thin circuit board based on polyimide films. Such circuit boards can advantageously be designed in a space-saving manner, in particular by folding or bending in the tightest structures, for example in lighting devices, and / or for connecting two rigid circuit boards, for example in

[0015] Lighting devices. Further preferred embodiments relate to a method for producing an electrically conductive contact connection between a first circuit board and a second circuit board by means of a connecting pin, wherein the first circuit board comprises a first opening in the region of the contact connection and the second circuit board comprises a second opening in the region of the contact connection, wherein a first section of the connecting pin is pressed into the first opening of the first circuit board, and subsequently a second section of the connecting pin is arranged in the second opening of the second circuit board such that a part of the second section protrudes from the second opening on a side of the second circuit board facing away from the first circuit board, and in a further step, a holding element is formed in the protruding part, which engages over the second circuit board such thatthat a positive connection is formed between the first and second circuit boards. The holding element comprises a resilient element or is designed as a resilient element.

[0016] Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description. Like reference numerals in different figures designate like or at least functionally comparable elements. They show, in schematic form: Fig. 1 shows an electrically conductive contact connection according to an embodiment not falling within the scope of the claims; Fig. 2 shows an electrically conductive contact connection according to the invention according to a preferred embodiment; Fig. 3 shows a terminal pin of an electrically conductive contact connection according to an embodiment not falling within the scope of the claims; Fig. 4 shows a terminal pin of an electrically conductive contact connection according to the invention according to a preferred embodiment, and Fig. 5 shows printed circuit boards connected to one another using contact connections according to the invention.

[0017] Fig. 1 shows an electrically conductive contact connection according to an embodiment not falling within the scope of the claims in a sectional view, which is designated in its entirety by the reference numeral 10. The contact connection 10 connects a first circuit board 12 to a second circuit board 14.

[0018] A first opening 16 is formed in the first circuit board 12 and a second opening 18 is formed in the second circuit board.

[0019] The contact connection 10 further comprises a connecting pin 20. The connecting pin 20 can also be referred to as a press-fit pin, for example. The connecting pin 20 is shown in a schematic sectional view in Fig. 3 The terminal pin 20 comprises a first section 22. According to the Figures 1 and 3 In the illustrated embodiment, the first section 22 is flexible. Upon insertion into the first opening 18 of the first circuit board 14, the first section 22 is compressed by contact with an inner wall 24 of the first opening 18, thereby creating a prestress and holding the first section 22 in the first opening 16. Thus, a press fit is formed by the section 22 arranged in the first opening 16.

[0020] The connecting pin 20 further comprises a second section 26, which is partially arranged in the second opening 18 of the second circuit board 14 to establish the electrically conductive contact connection 10. The second section 26 of the connecting pin 22 comprises a holding element 28. The holding element 28 engages over the second circuit board 14 on a side 30 facing away from the first circuit board, such that a positive connection is formed between the first and second circuit boards 12, 14.

[0021] The holding element 28 is in accordance with the Figures 1 and 3illustrated embodiment is formed by a plastic forming process. The second section 26 of the connecting pin 20 is plastically deformable at least in a part 32 protruding through the second opening in the second circuit board and beyond the second circuit board. The holding element 28 is then formed, for example, in a forming process, in particular a bending process or a riveting process, in particular as a rivet head. The forming takes place under the action of force using a suitable tool. The forming comprises, for example, a so-called upsetting of the connecting pin 20 and / or the pre-forming of part 32 of the second section 26 in the form of a rivet head, in particular by circular blows with a ball-head hammer, and / or the final forming of part 32 of the second section 26 in the form of a rivet head, in particular by means of a rivet head setter.

[0022] According to the Figures 2 and 4In the illustrated embodiments according to this invention, the holding element 28 is a resilient element 34. The resilient element 34 is compressed against the direction of the arrows 36 when the second section 26 is inserted into the second opening 18 and then springs up in the direction of the arrows 36 when the part 32 of the second section 26 protrudes from the second opening 18 on the side 30 facing away from the first circuit board 12. This then forms the holding element 28, which engages over the second circuit board 14 on the side 30 facing away from the first circuit board in such a way that a positive connection is formed between the first and second circuit boards 12, 14.

[0023] Furthermore, the first section 22 of the terminal pin 20 is in accordance with the Figures 2 and 4The illustrated embodiments are solidly formed. Upon insertion of the first section 22 into the first opening 16, the first circuit board 12 is deformed in the region of the first opening 16. This is also referred to as a non-compressible press-in contact.

[0024] The connecting pin 20 can also comprise further combinations of the first and second sections 22, 26 (not shown). For example, a solid first section 22 can be combined with a deformable second section 26, and a flexible first section 22 can be combined with a second section 26 with a resilient retaining element 32.

[0025] The inner wall 24 of the first opening 16 of the first circuit board 12 and an inner wall 38 of the second opening 18 of the second circuit board 14 comprise an electrically conductive material. The connection pin 20 is formed at least partially from an electrically conductive material. The connection pin 20 is made, for example, from metal and / or an alloy and / or partially from plastic in combination with an electrically conductive material. The connection pin 20 contacts the inner walls 24, 38 of the first and / or second opening 16, 18 at least partially, preferably over their entire circumference, thereby forming an electrically conductive connection between the first circuit board 12 and the second circuit board 14.

[0026] According to the illustrated embodiments, the first and second openings 16, 18 have different diameters. This can prove particularly advantageous when establishing the electrically conductive contact connection 10. For example, the first section 22 of the terminal pin 20 can be assigned to the first opening 16, and the second section 26 of the terminal pin 20 can be assigned to the second opening 18.

[0027] Figure 5shows a side view of several printed circuit boards 12, 14 connected to one another by contact connections 10 according to the invention. The first printed circuit board 12 is a rigid printed circuit board, and the second printed circuit board 14 is a flexible printed circuit board. Furthermore, a further rigid printed circuit board 12' is provided. The first printed circuit board 12 comprises, for example, a glass fiber mat impregnated with epoxy resin, which is also known by the material identifier FR4, as a non-conductive carrier material. The second printed circuit board 14 is, for example, a particularly thin printed circuit board based on polyimide films. According to the illustrated embodiment, the second printed circuit board 14 is provided for connecting the two rigid printed circuit boards 12, 12'. Such a use is conceivable, for example, in lighting devices, in particular for connecting LED printed circuit boards.An LED circuit board comprises one or more LEDs, with multiple circuit boards being used in particular in lighting devices with multi-chamber reflectors and / or with multiple feed points.

Claims

1. Electrically conductive contact connection (10) between a first and a second circuit board (12, 14), comprising the first and the second circuit board (12, 14) and a connection pin (20), the connection pin (20) comprising a first portion (22) which is at least partially arranged in a first opening (16), formed in the first circuit board (12), to form a press fit, the connection pin (20) comprising a second portion (26) which is partially arranged in a second opening (18) formed in the second circuit board (14), the second portion (26) of the connection pin (20) comprising a holding element (28), and the holding element (28) engaging over the second circuit board (14) on a side (30) of the second circuit board (14) facing away from the first circuit board (12) in such a way that an interlocking connection is formed between the first and the second circuit board (12, 14), the first circuit board (12) being a rigid circuit board (12) and the second circuit board (14) being a flexible circuit board (14), characterized in that the holding element (28), for establishing the interlocking connection between the first and the second circuit board (12, 14), comprises a resilient element (34) or is designed as a resilient element (34).

2. Contact connection (10) according to claim 1, characterized in that the first portion (22) of the connection pin (20) is solid or flexible.

3. Contact connection (10) according to one or more of the preceding claims, characterized in that an inner wall (24) of the first opening (16) of the first circuit board (12) and / or an inner wall (38) of the second opening (18) of the second circuit board (14) comprises an electrically conductive material.

4. Contact connection (10) according to one or more of the preceding claims, characterized in that the connection pin (20) is at least partially made of an electrically conductive material.

5. Contact connection (10) according to one or more of the preceding claims, characterized in that the first and the second opening (16, 18) have differing diameters.

6. Method for establishing an electrically conductive contact connection (10) between a first, rigid circuit board (12) and a second, flexible circuit board (14) by means of a connection pin (20), the first circuit board (12) comprising a first opening (16) in the region of the contact connection (10) and the second circuit board (14) comprising a second opening (18) in the region of the contact connection (10), a first portion (22) of the connection pin (20) being pressed into the first opening (16) of the first circuit board (14), and then a second portion (26) of the connection pin (20) being arranged in the second opening (18) of the second circuit board (14) in such a way that a part (32) of the second portion (26) protrudes from the second opening (18) on a side (30) of the second circuit board (14) facing away from the first circuit board (12), and in a further step, a holding element (28) being formed in the protruding part (32), which holding element engages over the second circuit board (14) in such a way that an interlocking connection is formed between the first and the second circuit board (12, 14), characterized in that the holding element (28), for establishing the interlocking connection between the first and the second circuit board (12, 14), comprises a resilient element (34) or is designed as a resilient element (34).