DE102013022354B3 - Method for establishing an electrical connection and electrical connection - Google Patents

Abstract

Method for producing an electrical connection, in particular a plug connector, with the following steps: providing a first at least partially flat conductor (1) with a hole (2), providing a second conductor (10) which has a pin (12) with an end face (16), wherein the pin (12) has a hole (20) that extends completely through the pin (12), inserting the pin (12) into the hole (2) of the first conductor (1), spreading the Pin (12) of the second conductor (10) by introducing an expanding element (30) into the hole (20) of the pin (12) around the first conductor (1) and the second conductor (10) in the area of the hole (2) to deform in the radial direction in order to positively connect the pin (12) to the first conductor (1) along the central axis of the hole (2).

Description

Technical area

The present invention relates to a preferably permanent electrical connection, in particular of a plug connector. Such electrical connections and connectors are used in particular in motor vehicles. However, use in other areas, such as aircraft or watercraft, is also conceivable. In particular, it relates to a high-voltage connector or high-current connector or an associated electrical connection. For example, it can affect an angled connector. In this regard, a plug connector is a component that can be brought together with another component in order to create a plug connection. Plugs and sockets are mentioned as plug connectors purely as examples. The invention further relates to a method for producing such an electrical connection, in particular between electrically conductive parts of an above-mentioned plug connector and/or the production of such a plug connector.

State of the art

Decreasing resources of petrochemical raw materials, which in recent decades have been used primarily as fuel in internal combustion engines of motor vehicles, mean that mobility concepts are currently being increasingly developed in which the vehicles are driven by battery- or accumulator-fed electric motors alone or in combination with one another non-electric energy source, as a so-called hybrid drive.

The consequence of this is that classic 14V on-board electrical systems will in the future be supplemented or completely replaced by (traction) on-board electrical systems with significantly higher voltages of 200-750V (high voltage). As a result, the connection systems previously used to produce the on-board electrical systems can no longer be used because they cannot handle the phenomena associated with such high voltages.

At the same time, it is not possible to simply use connection concepts from stationary technologies in which similarly high voltages are used, as these are not designed for the conditions prevailing in motor vehicles.

In particular, the connections must be designed in such a way that the vibrations generated during vehicle operation do not negatively affect the quality of the connection in the medium and long term. This primarily concerns the quality of the contacting of the cables, often shielded cables, with significantly larger inner conductor cross-sections of 50 mm ² or more made of copper or increasingly also made of aluminum or alloys thereof.

Furthermore, high demands are placed on connections for electric and hybrid vehicles in terms of tightness. An intrusion of media, such as B. oil, antifreeze, road salt, liquid water or dust, which could have a negative impact on the quality of the connection in the medium term, must be avoided.

The connections must be designed in such a way that the temperatures occurring in vehicles from -40°C to 200°C have no influence on the functionality of the on-board electrical system.

Due to the spatial proximity to electronic devices, such as the infotainment systems of motor vehicles, complete shielding of the high-voltage (HV) on-board network must also be ensured in the connection area.

In addition, it must be avoided that people are harmed by contact with the live cables during operation or during the assembly or maintenance of the vehicles or in the event of accidents.

Ultimately, the production and assembly of the connection concepts must be carried out as resource-efficiently as possible, which means that the capital, time and material expenditure should be minimal.

From the DE 10 2012 201 123 B3 An angled connector is known in which a first inner conductor part (first conductor) and a second inner conductor part (second conductor) are connected to one another via a press fit. Such a press fit is also available in the DE 10 2007 057 443 A1 or the DE 198 51 790 A1 described.

From the US 5,513,933 A a screw-like rivet is already known. The DE 44 31 274 A1 describes a process in which two conductors are connected to one another in a form-fitting manner using a clinching process. From the DE 10 2007 057 501 A1 , the DE 102 59 803 B3 and the DE 10 2011 122 371 A1 Electrical connections are known that are made via a pin that has knurling in the connection area.

As a rule, copper or aluminum or alloys thereof are used as the material for the inner conductor parts. However, these materials have a certain tendency to flow (settling behavior) when pressed and later a tendency to creep. As a result, the connection only withstands relatively low pull-out forces, even with relatively high press-in forces. This is counteracted by making the press fit stronger and the wall thickness of the part into which it is pressed greater. However, this is disadvantageous from the perspective of costs and the manufacturing process.

Furthermore, it is often necessary to create a gas-tight connection. In the solutions known from the prior art, this can often only be achieved by using a seal.

Description of the invention

The object of the present invention is therefore to create a method for producing an electrical connection or such an electrical connection that enables cost-effective and simple production and yet achieves high extraction forces with a comparatively small connection area.

The task is solved by a method with the features of claim 1 and an electrical connection with the features of claim 9.

Advantageous refinements follow from the subclaims, the description of the invention and from the drawings.

The basic idea of the present invention is to electrically connect a first and a second conductor, in which a pin of the second conductor is inserted into a hole in the first conductor, the first and the second conductor in the area of the hole or pin in the radial direction deform that in addition to a preferred non-positive connection along the central axis of the hole (pressing in), a positive connection is also realized at least in a direction opposite to the direction of insertion of the pin into the hole, that is, an undercut is achieved. The latter is achieved by spreading the tenon.
The hole is a through hole and extends completely through the conductor from the first to the second side.

The first conductor can be a conductor that is at least partially flat and has a hole. At least in the flat area, the conductor has a first side and a second side opposite the first side. The hole can have a circular shape or be designed as a plurality or polygon. The first conductor can be, for example, a busbar, a current bridge, a lead frame, a contact plate or a circuit board.

The second conductor can be, for example, a contact sleeve. The second conductor has a pin with an end face at one of its ends. The pin can have a circular cross section, be a multi-tooth or a polygon. It may have the same cross-sectional shape as the hole or a different cross-sectional shape.

As a rule, copper or aluminum or alloys thereof are used as the material for the conductors. The contact sleeve and the busbar can be made from the same base material or different base materials. They can have a different structural state or a different strength (see also later).

According to one embodiment, the electrical connection can be used in a plug connector, in particular for use in the on-board electrical system of motor vehicles or other vehicles. Such a connector according to the invention is explained below as a plug, but can also be designed as a plug receptacle (socket) or form any other component of a plug connection. As a rule, such a connector has an electrically insulating housing.

The pin can have at least one recess in its circumference, which ends in front of the front side, so that a collar or web (undercut) is created at the front end of the recess. The recess can be, for example, a groove running in the axial direction of the pin or hole. Alternatively, a radially circumferential groove is also conceivable.

After inserting the pin into the hole, the first conductor is plastically deformed in a deformation area around the hole. In this case, an axially applied joining force can preferably be converted into a radial pressing force, so that material of the first conductor penetrates or flows into the recess. Due to the collar or web (undercut) formed by the recess, the pin and thus the second conductor can no longer be pulled out of the hole in the opposite direction to the insertion direction. It is held in a form-fitting manner opposite to the insertion direction and the pin is positively connected to the first conductor along the central axis of the hole.

Advantageously, the pin can be inserted into the hole by pressing the pin into the hole. Consequently, even at low With a small thickness (thickness) of the flat area of the first conductor (i.e. low press-in height), a high pull-out force can be achieved with simple and cost-effective production. In addition, a gas-tight connection is created. Furthermore, low contact resistances can be achieved due to the press connection, no additional parts such as contact plates or seals are required, production can be automated and a gas-tight connection is achieved.

In addition, a large contact force in the radial direction is advantageously achieved by converting an axial joining force into a radial pressing force, so that the pin is clamped in the radial direction and is also non-positively connected to the first conductor in the area of the recesses along the central axis.

According to a particularly advantageous embodiment and as already mentioned at the beginning, the first and second conductors are mounted in a housing and at the same time electrically connected. The housing can also serve as a processing tool and absorb the joining forces, whereby the electrical connection and thus the connector can be made compact. Preferably, the housing will be made in one piece from a suitable plastic.

The housing is preferably made of a material that is suitable for the temperatures of -40°C up to 200°C that occur when the connector is used in motor vehicles, and can absorb and transmit forces without significant deformation or tendency to break.

Such a housing can be produced inexpensively using a common injection molding process.

The housing has at least one cavity in which further components of the plug can be arranged. If the housing is to be used to produce a multiple, for example a double or triple, plug connection, several adjacent, electrically insulated cavities can be provided in the housing. Alternatively, a single sufficiently large cavity can be arranged in the housing and the individual plugs of a multiple plug connection are electrically separated from one another via insulation (insulating pieces or insulating section) to be arranged between them.

To arrange further components of the plug, the cavity is accessible via two openings, the openings being designed in such a way that the components for connection to a line of the vehicle electrical system and the components for connection to a corresponding element, such as a plug receptacle, are at an angle, preferably 90 °, are arranged to each other.

At least one inner conductor and one outer conductor are arranged in the cavity of the housing. The inner conductor is composed of a first line-side inner conductor part, for example the first conductor, and a second plug-side inner conductor part, for example the second conductor.

The first inner conductor part serves, for example, to contact a load conductor of a line of the vehicle electrical system and the second inner conductor part contacts a load conductor of a correspondingly designed plug receptacle.

The first and second inner conductor parts are preferably designed as components which have an outer contour through which the first and second inner conductor parts can be linearly inserted or pressed into the housing provided in each case and provided with openings in accordance with the contour of the inner conductor parts Existing components of the plug can be made at the time of assembly of the inner conductor. The first inner conductor part additionally has an opening which serves to accommodate the second inner conductor part laterally and corresponding geometrically with the outer contour of the second inner conductor part.

The first inner conductor part can be surrounded by an insulator and the insulator is arranged in a form-fitting and positionally fixed manner, preferably non-positively, in the first outer conductor part. The insulator preferably has a lateral opening through which the second inner conductor part penetrates.

It should be possible to produce the electrical connection of the present invention in the housing itself, for which purpose the first conductor (for example of the first inner conductor part) is preferably first introduced into the housing and by inserting the second conductor (for example of the second inner conductor part). electrical connection can be realized.

According to an advantageous embodiment of the present invention, several of the depressions are provided in the pin, which are distributed over the circumference of the pin. For example, several parallel grooves can be provided. For example, these grooves can extend parallel along the axial direction or can also run annularly and be arranged parallel to one another in the axial direction. Furthermore ent There is also a positive connection through the recess in the radial direction. This can be further enhanced if there are several depressions that run in the axial direction.

In order to be able to produce these depressions as simply and cost-effectively as possible, the depressions are preferably formed by knurling or introduced by knurling. The knurling can preferably be recessed, but can also be raised. The knurling tool is preferably designed to be slightly shorter than the tenon or in two parts in order to create the collar or web or to ensure that the recesses end in front of the end face of the tenon. For example, the knurl can be made 0.3 mm to 0.8 mm shorter than the tenon.

According to a particularly preferred embodiment, the deformation region of the first conductor is deformed by a shoulder or a press-in element of the second conductor, which adjoins the pin, while the pin is inserted or pressed into the hole. This means that no additional tools are necessary. In addition, the electrical connection or the plug connector can remain compact, since no additional space has to be created for a tool to be inserted separately.

In order not to reduce the cross section of the first conductor in the deformation area and thus increase the contact resistance, it is advantageous to form the deformation area of the first conductor by a raised edge surrounding the hole. Such an edge is also called a pull-through.

It can be formed when forming the hole by displacing material from the second side of the first conductor to the first side of the conductor when the hole is introduced. This gives the passage a sleeve shape or a conical sleeve shape compared to a flat or straight bore. An accumulation of material is thus formed on the first side of the first conductor. During plastic deformation, in particular when joining the first and second conductors (insertion of the pin into the hole), this accumulation of material can be pressed and compressed in the axial direction and radial direction and leads to the material of the first conductor penetrating into the recess and preferentially the pin is stuck.

The pin is expanded by inserting an expanding element into the hole of the pin and thereby displaces material of the first conductor in the radial direction. By spreading the pin to form a cone or truncated cone, an undercut is created, which connects the pin to the first conductor in a form-fitting manner along the central axis of the hole. In other words, the spreading creates a conical area in a section of the tenon, which forms the undercut and realizes the positive fit.

The expansion element can be formed, for example, by a grub screw or by a pin that is pressed into the hole in the second conductor. The grub screw can have a self-tapping or self-tapping thread, whereby the grub screw and the second conductor are also connected to one another in a form-fitting and undercut manner. When using a pin that is pressed in, only a frictional connection is created between the expansion element and the hole in the second conductor.

In order to be able to form the electrical connection in said housing, it is preferred to introduce the expansion element into the hole of the pin from the opening of the hole located opposite the end face, in particular to screw it in or press it in. This opening is accessible via the housing opening and is therefore best suited for this purpose. Alternatively, it is also conceivable to form the expansion element in the housing, with the expansion element being inserted into the hole in the pin when the pin of the second conductor is joined into the hole of the first conductor, which is then open at least on the end face of the pin.

In order to reduce the required compression forces of the press-in element, it can be advantageous to introduce several continuous slots into the pin, which advantageously extend in the axial direction over the area of the pin to be expanded.

In order to realize spreading, either the expansion element is conical, particularly when it is inserted into the pin from the front side, or, according to a preferred embodiment, the hole in the pin, whereby it advantageously tapers towards the front side. In this respect, the expansion element can be designed cylindrical in this case. However, the hole and expansion element can also be conical.

In addition to forming an undercut by spreading the pin, the pin is also clamped in the radial direction by the material of the first conductor and non-positively connected to the first conductor along the central axis. This means that in addition to the positive fit, a press fit with good contact resistance can also be achieved.

In addition, it is preferred to make the deformation resistance of the first conductor different from that of the second conductor. In particular, the resistance to deformation of the second conductor is greater. For example, the second conductor may have greater strength than the first conductor. This can ensure that a reliable positive fit is achieved during deformation. Material of the first conductor can reliably penetrate into the depression or depressions of the pin and the spreading of the pin can lead to a deformation or displacement of material of the first conductor.

Further advantages and features of the present invention, which can be implemented alone or in combination with one or more of the above-mentioned features, emerge from the following description of preferred embodiments. It goes without saying that individual features can also be taken from this and combined with individual features as explained above, provided that the features are not mutually exclusive.

Short character description

• 1 perspektivisch einen ersten Leiter gemäß einer nicht beanspruchten Ausführungsform in Form einer Kontakthülse;
• 2 den zweiten Leiter aus 1 während dem Einführen des Zapfens in das Loch des geschnitten dargestellten ersten Leiters, wobei in 2a und 2b unterschiedliche Ausgestaltungen eines das Loch umgebenden erhabenen Rands darstellen;
• 3 die Ausgestaltung aus 2 im vollständig verbundenen Zustand;
• 4a eine elektrische Verbindung einer Ausführungsform der vorliegenden Erfindung a) bevor das Spreizelement eingeführt wurde und b) nachdem das Spreizelement eingeführt wurde;
• 5 eine elektrische Verbindung gemäß der Ausführungsform in 4, wobei im Zapfen zusätzlich Schlitze ausgebildet sind; und
• 6a, 6b Vertiefungen am Zapfen in Form von Rillen und Rippen.

Below show:

• 1 perspectively a first conductor according to an unclaimed embodiment in the form of a contact sleeve;
• 2 the second leader 1 during the insertion of the pin into the hole of the first conductor shown in section, whereby in 2a and 2 B represent different configurations of a raised edge surrounding the hole;
• 3 the design 2 in fully connected state;
• 4a an electrical connection of an embodiment of the present invention a) before the expansion element was inserted and b) after the expansion element was inserted;
• 5 an electrical connection according to the embodiment in 4 , with additional slots being formed in the tenon; and
• 6a , 6b Depressions on the tenon in the form of grooves and ribs.

In the individual illustrations, the same reference numbers are used for the same or comparable elements. These same elements will not be described again in the different embodiments.

1 shows a second conductor, for example a plug-in inner conductor 10, which is in the embodiment in 1 is designed in the form of a contact sleeve, as shown in section 4 and 5 can be seen. The contact sleeve consists of a substantially cylindrical receiving section 11, which is designed to receive a plug. At one end of this cylindrical receiving section 11, a pin 12 is provided in one piece. This is also essentially cylindrical and has a knurl 13 over its entire circumference. The pin here has a total height H starting from the end of the receiving section 11. The knurling has a height H _R that is smaller than the height H. In the exemplary embodiment, the knurling is 0.5 mm smaller than the total height H of the tenon. This can be achieved by designing the knurling tool according to the height H _R , that is to say it is slightly shorter than the pin 12.

The knurls result in several depressions 14, each of which runs in the axial direction A and are each arranged parallel to one another. The individual depressions 14 are separated from one another by parallel ribs 15. Depending on the knurling tool, these can have a triangular, i.e. pointed, shape or a trapezoidal, i.e. blunt, shape. The depressions 14 end at a distance which corresponds to the difference between the height H and the height R, in front of the end face 16 of the pin. As a result, a web or collar 17 is formed at the front end of the recesses 14, which can have an outer circumference or diameter which corresponds, for example, to the top of the ribs 15, for example the tips or their diameter.

Out of 2 a first conductor 1 can be seen in the form of a busbar. This has a first page 3 and a second page 4 opposite the first page. Furthermore, a through hole 2 is provided, for example in the form of a bore, which extends from side 4 to side 3. This hole 2 is designed as a so-called passage, so that a raised edge (passage) 18 is formed on the first side 3 of the first conductor 1, which protrudes from the first side 3 of the first conductor 1. This can have a conical sleeve shape, as in 2a , or a cylindrical sleeve shape, as in 2 B , exhibit.

Such passages are advantageously introduced when the hole 2 is introduced into the first conductor 1 by plastically deforming the material into the desired shape of the passage 18 or the raised edge when the hole is introduced.

In 2 the pin 12 of the second conductor 10 is already inserted into the hole 2 of the first conductor. This is advantageously done in such a way that the first conductor 1 is first inserted into an advantageously integrally molded plastic housing and in a second step the second conductor 10 is introduced through another opening in the housing and the pin 12 is inserted into the hole 2.

The diameter of the hole 2 on the first side 3 of the first conductor 1 can have a smaller diameter than the outer diameter, which is formed by the web or collar 17 or the top sides of the ribs 15. To insert the pin 12 into the hole, it must therefore be pressed or inserted. In a further variant, the diameter of the hole 2 should be slightly larger than the outer diameter of the pin 12 so that the pin 12 is centered in the hole before the joining process.

Furthermore, the outer diameter of the pin 12 is designed to be smaller than the diameter of the receiving area 11. As a result, a shoulder 19 is formed at the transition between the receiving area 11 and the pin 12.

During the further joining process, the shoulder 19 comes into contact with the raised edge 18. If the joining process, which takes place along the axial direction A through a movement of the second conductor 10 towards the first side 3 of the conductor 1, progresses, the raised edge 18 is deformed in the axial direction and radial direction. As a result, material of the first conductor 1 penetrates into the recesses 14 between the ribs 15 and simultaneously clamps against both the ribs 15 and the bottom of the recesses 14 in the radial direction. As a result, the pin 12 is non-positively connected to the first conductor 1 along the axial direction A in the manner of a press fit.

Furthermore, material portions of the first conductor 1 are present in the recesses 14, so that the collar 17 forms an undercut and thus forms a positive connection against the joining direction F. At the same time, the ribs 15 form a positive connection in the circumferential direction and the shoulder 19 form a positive connection in the joining direction.

This means that good to very good pull-out forces can be achieved even with comparatively low press-in forces or joining forces. Furthermore, a gas-tight connection with low contact resistance is achieved without the need to use additional parts such as seals or contact plates.

4 represents an embodiment of the present invention.

A hole 20 is provided in the pin 12, which has an opening 21 which opens into the receiving area 11 and an opening 22 on the end face 16 of the pin 12.

Otherwise, the tenon also has a knurl, as described in reference to the 1 to 3 was explained. However, this can also be omitted.

The hole 20 in the second conductor 10 is conical in an area 23. This area 23 runs in such a way that it tapers towards the end face 16 of the pin 12.

Furthermore, an expanding element 30 is provided. This can be designed in the form of a grub screw with a self-tapping thread or conventional external thread or as a pin for pressing in in the joining direction F.

In this embodiment too, the outer diameter of the pin 12 can be designed to be larger than the inner diameter of the hole 2 in the first conductor 1, so that the pin 12 has to be pressed in during insertion.

The expansion element 30 is designed essentially cylindrical and in the 4 and 5 only half shown.

The embodiment in 5 only differs in that 12 slots 24 are provided in the conical section 23 of the pin, which make this section easier to expand.

It is preferred to first place the first conductor 1 in a housing and to connect the electrical connection electrically and mechanically by inserting the second conductor 10. For this purpose, the pin 12 is first inserted into the first conductor 1 in the joining direction F, whereby a non-positive connection is already achieved. After the pin 12 has been completely inserted into the hole 2, the expansion element 30 is pressed or screwed in in the joining direction F. The area 23 is expanded by the conically shaped area 23 and the cylindrical expanding element 30, as shown in 4b is shown by the dashed lines. As a result, material of the first conductor 1 is displaced in the radial direction and, by spreading, a positive connection is achieved against the joining direction F. Insofar as the knurling 13 is provided, there is also a positive connection in the circumferential direction, as well as a positive connection through the web 17. However, it is understood that the knurling delung 13 and/or the web 17 can be omitted in this embodiment.

In addition, due to the material displacement, material of the first conductor 1 is pressed radially against the pin 12 in order to realize or support a non-positive connection along the axial direction A here too.

Furthermore, the pull-out force can be increased by radially mounted depressions 14 in the form of grooves or ribs, see 6a and 6b .

In this embodiment, high pull-out forces can be achieved through relatively low joining forces and a gas-tight connection can be guaranteed without additional parts.

It is understood that various variations and modifications of the present invention are possible within the scope of the overall teachings. The first and second conductors do not have to be designed as a busbar and contact sleeve. It is also conceivable to use the present invention with angled plug connectors, but the invention is by no means limited to this application. Accordingly, the scope of protection is defined by the following patent claims.

Claims (12)

Method for producing an electrical connection, in particular a plug connector, with the following steps: Providing a first conductor (1) which is at least partially flat and has a hole (2), Providing a second conductor (10) which has a pin (12) with an end face (16), the pin (12) having a hole (20) that extends completely through the pin (12), Inserting the pin (12) into the hole (2) of the first conductor (1), Spreading the pin (12) of the second conductor (10) by introducing an expanding element (30) into the hole (20) of the pin (12) in order to move the first conductor (1) and the second conductor (10) in the area of the hole ( 2) to deform in the radial direction in order to positively connect the pin (12) to the first conductor (1) along the central axis of the hole (2). Procedure according to Claim 1 , in which the expansion element (30) is screwed or pressed in. Procedure according to one of the Claims 1 until 2 , in which the pin (12) has one or more slots (24) which are open on the end face (16). Procedure according to one of the Claims 1 until 3 , in which the hole (20) in the pin (12) is at least partially conical, in particular tapering towards the end face (16). Procedure according to one of the Claims 1 until 4 , in which the pin (12) is spread open in such a way that the pin (12) is clamped in the radial direction and non-positively connected to the first conductor (1) along the central axis. Procedure according to one of the Claims 1 until 5 , in which the pin (12) comprises one, preferably several, recesses (14) in its circumference, which ends in front of the end face (16), with material of the first conductor (1) being spread into the pin (12) when the pin (12) is spread Recess(s) (14) penetrates and positively connects the pin (12) to the first conductor (1) along the central axis of the hole (2). Procedure according to Claim 6 , in which the depressions (14) are made by knurling. Electrical connection, in particular of a plug connector, comprising: a first at least partially flat conductor (1) with a hole (2), a second conductor (10), which has a pin (12) inserted into the hole (2) of the first conductor (1) with an end face (16), the pin (12) having a hole (20) that is completely extends through the pin (12), an expansion element (30) inserted into the hole (20) of the pin (12) in order to deform the first conductor (1) and the second conductor (10) in the region of the hole (2) in the radial direction in order to move the pin (12) to be connected positively, in particular non-positively and positively, to the first conductor (1) along the central axis of the hole (2). Electrical connection after Claim 8 , in which the expansion element is non-positively and positively connected to the second conductor (10). Electrical connection according to one of the Claims 8 until 9 , in which the pin (12) has one or more slots (24) which are open on the end face (16). Electrical connection according to one of the Claims 8 until 10 , in which the pin (12) comprises one, preferably several, recesses (14) which ends in front of the end face (16), with material of the first conductor (1) engaging in the recess(es) (14) and the Pin (12) positively connects to the first conductor (1) along the central axis of the hole (2). Electrical connection according to one of the Claims 8 until 11 , wherein the deformation resistance of the first conductor (1) is different, in particular lower, than that of the second conductor (10).

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