WO2018114265A1

WO2018114265A1 - Method for electrically contacting a printed circuit board with a pin

Info

Publication number: WO2018114265A1
Application number: PCT/EP2017/080918
Authority: WO
Inventors: Andreas Gerl; Bernhard Schuch; Thomas Schmidt; Karin Beart; Kurt Gross; Mathias Strecker; Martin Steinau
Original assignee: Conti Temic Microelectronic Gmbh
Priority date: 2016-12-21
Filing date: 2017-11-30
Publication date: 2018-06-28
Also published as: DE102016225714A1

Abstract

The invention relates to a method for electrically contacting a printed circuit board (4) with a pin (5). The surface of the printed circuit board (4) is metallized in a connection region (9) in which a receiving area (6) for the pin (5) is located and in which an electric contact is produced between the printed circuit board (4) and the pin (5). The printed circuit board (4) is electrically contacted with the pin (5) in the connection region (9) by pressing the pin (5) into the printed circuit board (4). The printed circuit board (4) and the pin (5) are then encased with a casing (11) made of a duroplastic material in the connection region (9).

Description

description

Method for electrically contacting a printed circuit board with a pin

The invention relates to a method for electrically contacting a printed circuit board with a pin.

It is known to contact a printed circuit board with a pin, in particular in the form of a copper stamped grid, by means of press-fitting. Such a press-fit technique represents a cost-effective and reliable connection technology for electrical contacting. In the automotive sector, press-fit technology has a broad application, since it can be used in a temperature range from -40 to 150 ° C., has high vibration resistance (> 30 g), low Übergangswi ^¬ resistors causes (<< LMQ) and thus ensures a high current carrying capability ^¬. Furthermore, the press-fit technology represents a simple and stable production process without tempering of the printed circuit board and generates only very low failure rates or ensures a high reliability.

Due to the influence of aggressive corrosion-demanding media, the reliability and thus the application of press-fit technology is severely limited. For example, transmission oils in the liquid and gaseous state can have a damaging effect on the electrical and mechanical function of the press-fit connection. Among other things, this depends on the sulfur content of the oil, the external temperatures and the residence time of the press-in compound in the corrosion-requiring medium. Reliable protection of the electrical connection from the direct influence of corrosion-prone media, for example in inte- grated transmission controls is not known from the current state of the art.

It is the object of the present invention to provide a method for electrically contacting a printed circuit board with a pin, which allows an increase in reliability, in particular of integrated transmission controls at a particularly low cost of contacting.

The object is solved by the subject matters of the independent claims. Advantageous embodiments are subject of the dependent claims, the following description and the figures.

According to a first aspect of the invention, there is provided a method of electrically contacting a printed circuit board with a pin. The pin may in particular be a stamped grid, for example a copper stamped grid. According to the method of the invention, a pin and a circuit board are provided with a receptacle for the pin. A surface of the circuit board is metallized in a connection region, for example by chemical tin or OSP (Organic Surface Protection). This allows a reliable application of a press-fit technique, which will be applied below. In the Verbin ^¬-making area it is recording. In addition, the electrical contact between the circuit board and the pin is provided in the connection region.

In a further step, first the printed circuit board is electrically contacted with the pin in the connection area, for which purpose the pin is pressed into the printed circuit board. Subsequently, in a further step, the printed circuit board and the pin in the connection region are encased with a cladding made of a thermoset material, which is preferably made of an epoxy-based material System with glass particle filling exists. In other words, in the method according to the invention, a press-fit connection between the printed circuit board and the pin is first produced in a standard method. The press-fit connection is then completely sheathed by a Duro ^¬ plast material and thus gas-tight manner protected from corrosive media in a further production step. As an alternative to the thermosetting material, a thermoplastic material can also be used as described above.

The above-described method for electrically contacting a printed circuit board with a pin is also suitable for electrically contacting a multiplicity of pins with the printed circuit board as described above, for which in particular a corresponding number of recordings of the printed circuit board are provided and the method steps described above be repeated accordingly or can be carried out at the same time. A particular advantage of coated in this way is press-fit the associated additional me ^¬ chanical fixation of the electrical interface. Due to thermal and chemical crosslinking, the cladding material is subject to shrinkage. By carefully adjusting the Umhüllwerkstoffs this loss can be used to induce specific tensions and to ensure optimum mechanical Fes ^¬ ACTION. Additional pins to increase the mechanical strength can thus be saved and the space and costs are reduced.

Another advantage of the invention is that a media exchange between a top and a bottom of the circuit board can be prevented. Standard pressfit connections however, they require an open via of the circuit board, allowing for media exchange.

In contrast to standard potting materials, cladding with Duroplastwerkstoffen show particular advantages. They bond gas- ^tightly at an interface between the printed circuit board and the pressed-in pin. Thus, in addition, the PCB surface is protected from corrosion by defective media. Another advantage of using wrapping materials

Duroplast is the low swelling behavior due to the absorption of water. This is not accompanied by a noticeable change in physical properties.

Special advantages are also to be expected over coated solder joints. Fluxes can affect the connection of the envelope to the circuit board, which are eliminated when using press-fit technology.

The method according to the invention can be used in all areas in which a press-fit connection is to be protected from defective media or the reliability is to be increased or the mechanical stability has to be improved. Ins ^¬ particular, the reliability of an integrated Ge ^¬ gear control with a printed circuit board, which is according to the invention is contacted with a pin electrically be increased.

When wrapping process temperatures up to 180 ° C are possible, which are therefore above the usual operating temperatures. It should be noted that the materials and geometries of the individual components are ideally matched to the wrapping process. According to a further embodiment, it is therefore provided that the pin is made of a copper alloy, which is so be ^¬ create that the pin after wrapping at Prozesstem- temperatures up to 180 ° C permanently exerts a pressing force on the circuit board, which causes an electrical contact between the circuit board and the pin. Alternatively or additionally, the pin may have a coating which is such that the pin after wrapping at process temperatures up to 180 ° C permanently exerts a contact pressure on the circuit board, which causes an electrical contact between the circuit board and the pin.

Furthermore, the pin may have a geometry which is such that the pin after wrapping at process temperatures up to 180 ° C permanently exerts a contact pressure on the circuit board, which causes an electrical contact between the circuit board and the pin.

According to a further embodiment it is provided that the circuit board is made at least in the connection region of a material which is such that the circuit board of the permanent contact pressure of the pin and the process temperatures occurring during wrapping up to 180 ° C and a durable electrical Contact between the circuit board and the pin causes. In this context, it may in particular be provided that the printed circuit board is made of a material whose glass transition temperature is matched to the process temperatures during the coating.

According to a second aspect of the invention, there is provided a printed circuit board having at least one pin, wherein the printed circuit board has been electrically contacted with the at least one pin according to a method of the first aspect of the invention. According to a third aspect of the invention, an electronic control unit for a component of a motor vehicle is provided ^¬ , wherein the electronic control unit comprises a printed circuit board according to the second aspect of the invention. The component of the motor vehicle may in particular be a transmission of the motor vehicle. In this case, the electronic control unit within the transmission of the power ^¬ vehicle is an integrated transmission control. Furthermore, it could also be a drive motor, such as an internal combustion engine, or a brake system in the component of the motor vehicle.

According to a fourth aspect of the invention, a motor vehicle is provided, which comprises an electronic control unit according to the third aspect of the invention. The vehicle is, for example, a motor vehicle, such as a car, bus or truck.

Embodiments of the invention are explained in more detail below with reference to the schematic drawing. This shows

1 is a side view of a vehicle with a gear and a housing which receives a board with at least one pin,

Fig. 2 is a partial cross-sectional view through in the

Housing of Fig. 1 recorded circuit board with the at least one pin, wherein the circuit board and the

Pin are electrically contacted by pressing together,

3 is a partial cross-sectional view through the circuit board and the pin of FIG. 2, wherein the input Press connection between the circuit board and pin have been wrapped with a wrapping material.

Fig. 1 shows a vehicle in the form of a motor vehicle 1. The motor vehicle 1 includes, inter alia, a transmission 2, within which a housing 3 is arranged. The housing 3 is un ^¬ indirectly installed in a transmission oil of the transmission 2 and receives in its interior a circuit board 4 having a plurality of pins 5 (FIG. 2 and 3). The housing 3, together with the board 4 and the plurality of pins 5, an electronic control unit. Next to the

Transmission 2, the motor vehicle 1 further includes in particular ^¬ special a motor and a brake system (both not shown), both of which may also have a housing 3 with a board 4.

FIGS. 2 and 3 show a portion of a provided board 4 and one of a plurality of provided pins 5. The board 4 and pins 5 may be received by the housing 3 of FIG. The board 4 is provided with a receptacle 6, which connects a bottom 7 and a top 8 of the circuit board 4 together. The pin 5 is received in a connection region 9 within the receptacle 6.

On one surface of the printed circuit board 4 is in the connection area 9, in which the receptacle 6 is located and in which a contact between the circuit board 4 and the pin 5 is provided, a surface metallization 10 is applied, for example in the form of chemical tin or OSP , The surface metallization 10 was first applied and then the pin 5 was inserted by pressing into the receptacle 6 with the surface metallization 10. FIG. 3 shows the printed circuit board 4 and the pin 5 after the printed circuit board 4 and the pin 5 have been completely enveloped in the connecting region 9 with a cladding 11 made of a thermoset material. The envelope 11 is applied directly to the surface of the circuit board 4 and directly on the surface of the pin 5.

In Fig. 3 F _F spring forces are further represented by double arrows, which indirectly exerts the pin 5 on the circuit board 4 and directly on the surface metallization 10. The double arrows F _{F also} present a corresponding counterforce of the printed circuit board 4 on the pin 5 and on the surface metallization 10. Due to thermal and chemical crosslinking, the sheath 11 is subjected to a shrinkage, which induces a voltage which determines the strength of the connection between pin 5 and PCB 4 increased. A shrinkage force corresponding to this tension is illustrated by further arrows F _s .

Claims

claims

1. A method for electrically contacting a printed circuit board

(4) with a pin (5), the method comprising the steps: - providing a pin (5) and a printed circuit board (4) with a receptacle (6) for the pin (5),

Metallizing a surface of the printed circuit board in a connection region in which the receptacle is located and in which an electrical contact is provided between the printed circuit board and the pin;

- electrically contacting the printed circuit board (4) with the pin (5) in the connecting region (9) by pressing the pin (5) into the printed circuit board (4) and

- Encasing the printed circuit board (4) and the pin (5) in the connection area (9) with a sheathing (11) made of a thermoset material or thermoplastic material.

2. The method of claim 1, wherein the pin (5) is made of a copper alloy, which is such that the pin (5) after wrapping at process temperatures up to 180 ° C permanently exerts a contact pressure on the circuit board (4) , which causes an electrical contact between the printed circuit board (4) and the pin (5).

3. The method according to claim 1 or 2, wherein the pin (5) a

Having coating, which is such that the pin

(5) after wrapping at process temperatures up to 180 ° C permanently exerts a contact pressure on the circuit board (4), which causes an electrical contact between the circuit board (4) and the pin (5).

4. The method according to any one of the preceding claims, wherein the pin (5) has a geometry which is such that the pin (5) after wrapping at process temperatures up to 180 ° C permanently exerts a contact pressure on the circuit board (4), which causes an electrical contact between the circuit board (4) and the pin (5).

5. The method according to any one of the preceding claims, wherein the circuit board (4) is made at least in the connection region (9) of a material which is such that the circuit board (4) of the permanent contact force of the pin (5) and the at Enveloping occurring process temperatures of up to 180 ° C withstands and causes a permanent electrical contact between the circuit board (4) and the pin (5).

6. The method according to claim 5, wherein the circuit board (4) is made of a material whose glass transition temperature on the

Process temperatures is adjusted during the wrapping.

7. printed circuit board (4) having at least one pin (5), wherein the printed circuit board (4) has been electrically contacted with the at least one pin (5) according to a method according to one of the preceding claims.

8. Electronic control device for a component (2) of a motor vehicle (1), the electronic control device comprising a printed circuit board (4) according to claim 7.

9. Motor vehicle (1) comprising an electronic control unit according to claim 8.