EP3189561B1 - Crimp contact - Google Patents

Description

In a first aspect, the invention relates to a crimp contact according to the preamble of independent main claim 1.

The invention also relates to a heavy-duty connector with the crimp contact.

The invention also relates to a method for using the crimp contact
In a further aspect, the invention relates to a method for producing the crimp contact, with an additional silver coating.

Such connectors and contacts are used to transmit an electrical current with currents of 500 to 650 A, for example, between electrical conductors.

State of the art

In the prior art, it is known to use both copper lines and aluminum lines for electrical energy transmission, particularly in the high-current range. For example, at the time in the GDR, aluminum was primarily used as an available raw material for this purpose. Usually this was done in the form of relatively rigid individual conductors, so that such power supply lines can also be found today in the new federal states. In contrast, stranded conductors made of copper were predominantly used in the old federal states in the past.

Due to the current prices and the limited availability of copper resources and also due to the significantly lower specific weight (AL: 2.73 kg / dm ³ ; CU: 8.9 kg / dm ³ ), it is increasing in many areas today Aluminum used as a material for high-current electric transmission lines. The more flexible, ie less rigid, stranded conductors are preferably used. The power transmission can take place both above ground, for example in wind turbines and in the railway sector, but also in the case of underground power distribution, for example in the form of underground lines as part of a larger power distribution network. The somewhat lower specific conductance of aluminum and the resulting correspondingly larger cable cross-sections are accepted in favor of the aforementioned advantages.

The increasing use of aluminum cables in wind turbines is in the publication WO 2013 174 581 A1 mentioned. The use of electrical connectors for electrically connecting different cables is also described. The use of crimp and screw connections is mentioned. In order to avoid the disadvantages caused by the oxidation at the transition from the aluminum strands to the connector, it is proposed that the cables be welded to the connection surfaces of the connector, for example by friction welding.

It is also mentioned that the connection between the aluminum cable and the connector can take place by friction welding, rotational friction welding, ultrasonic welding or resistance welding. The connector can be formed from copper. Alternatively, it is disclosed that the connecting piece is also formed from aluminum in order to avoid contact resistance or contact corrosion at the junctions between the aluminum cable and the Avoid contact piece. Furthermore, tinning or tinning and nickel plating of the surface of the connecting pieces is proposed.

From the pamphlet DE 10 2013 105 669 A1 it is also known to connect electrical connectors to a stranded conductor by resistance welding.

The pamphlet EP 1 032 077 A2 suggests in this context connecting a stranded conductor made of aluminum to a contact part made of copper by friction welding.

The pamphlet EP 2 621 022 A1 describes a cable lug for connecting a current-carrying element to an aluminum cable, a first section of an associated pipe having an aluminum layer on an inside and a copper layer on an outside.

EP 2 662 934 A2 suggests the use of a connection cap made of aluminum or an aluminum alloy. This connection cap is pressed with the aluminum conductor and welded to the contact part made of copper or a copper alloy.

In principle, the assembly of these types of construction, in which the stranded conductor is welded directly or indirectly to the contact, is unfortunately very complex and cannot be carried out on site without appropriate devices, so that this type of construction cannot be assembled in the field.

The DE 11 2011 103 392 T5 discloses a crimp termination made from two different metal materials, such as copper and aluminum. The connection area between these two materials is covered with a plastic molded part to prevent corrosion.

The pamphlet EP 2 579 390 A1 also describes an aluminum-copper terminal that has a contact part made of aluminum and a connection part made of copper, which are welded to one another, the connection area being protected against electrical corrosion by attaching a primary seal, for example by overmoulding with a special thermoplastic Strand is welded to the contact part.

It is therefore proposed in these two last-mentioned two publications to seal the relevant transition area with a seal, for example by overmolding with a special thermoplastic. On the one hand, this process is complex and, on the other hand, such a seal usually only has a limited service life. A connector formed in this way is not suitable as a contact element for a connector.

The aforementioned documents also relate to connectors with which a supply cable is permanently connected to a power rail or to another cable for permanent installation. This installation is installed once and is basically not intended to be changed frequently.

In contrast, in the prior art, for example from the publication EP 892 462 B1 , also known electrical heavy-duty connectors that have crimp contacts, and the cable connection technology is therefore much easier.

The pamphlet DE 2 601 952 A1 refers to a connector made of aluminum and an opening or hole having. The connector is intended to be clamped to one or more electrical lines, which are also made of aluminum, when these are inserted into the opening. The clamping should preferably be done with the help of a mold.

The pamphlet GB 982 667 A discloses a method for improving electrical connections and thereby discloses a clamping sleeve with an internal thread and a screw mandrel.

The pamphlet U.S. 3,350,500 A discloses a method for butt splicing coaxial cables having a core and barrel conductors separated by dielectric material. It is disclosed here that the sleeve conductors are expanded outward at the cable ends and the core conductors are connected by connecting plugs which penetrate the cable ends essentially axially and connect the sleeve conductors by a conductive sleeve.

The pamphlet EP 1 094 557 A2 relates to a high-current circuit board connector for vibration-free contacting of circuit board connection contacts and main contacts to be plugged over, whereby the socket part of the high-current circuit board connector can be mechanically fitted to circuit boards with alignment in board bores. The main contacts are made of copper and silver-plated on the outside.

The pamphlet U.S. 3,916,518 A discloses a method of making a one-piece bimetallic connector.

The pamphlet EP 0 023 880 A1 discloses a plug element which consists of a plug part and a compression sleeve. So that the outer diameter of the compression sleeve is always smaller than the associated wire diameter, the compression sleeve is designed with at least two layers forms. An inner layer made of copper or aluminum takes on the function of conducting electricity, while an outer layer made of steel ensures the contact pressure after the pressing process.

Even in this case, however, the problem remains that the strands of the aluminum conductor have a poor relationship with one another due to their oxidation have so-called "transverse conductivity" (ie the conductivity between the individual strands perpendicular to the course of the cable), which also increases the transition resistance to the connection contact in all the arrangements described.

Furthermore, there is still the problem that aluminum easily oxidizes and continues to combine with other metals such as e.g. Copper or brass badly connects. This applies in particular to stranded aluminum conductors due to their large surface area. In the transition area between aluminum and copper, for example, so-called "electrocorrosion" occurs, especially when long-term current is applied with high currents and under the simultaneous influence of oxygen, and thus a layer that has a significantly higher specific resistance than any of the metals involved. Due to this high resistance, strong heating can take place during operation due to the high current strengths, through which this contact resistance is additionally increased in the form of an interaction. This heat development can also result in further consequential damage, for example to plastic insulation.

For example, in the railway sector, but also in many other areas, there are applications that require frequent changes to the high-current electrical wiring. Thus, in the prior art, there is a need for high-current connectors that can be flexibly maneuvered, which can preferably be assembled in the field or at least can be assembled with as little effort as possible.

Task

The object of the invention is thus to provide an electrical connector which, on the one hand, allows a comparatively uncomplicated connection of an aluminum stranded conductor, and on the other hand also enables the most flexible maneuvering possible and which continues to have a sustained good electrical conductivity even with high currents acting over a long period of time.

The object is achieved by the features of the independent main claims.

Advantageous embodiments of the invention are specified in the subclaims.

According to the first aspect, the invention is a crimp contact; wherein the crimp contact has a crimp area formed from aluminum or an aluminum alloy and an adjacent contact area formed from copper or a copper alloy, wherein the contact area can be designed in the shape of a pin or socket. In this way, an aluminum stranded conductor can be crimped with the crimping area without causing so-called "electrical corrosion".

According to the invention, the transition from the copper to the aluminum material is moved into the crimp contact. This is made possible by the crimping area being welded to the contact area. In particular this connection is made during the production of the crimp contact by a friction welding process.

The crimp contact can therefore be a high-current capable contact pin or a high-current capable contact socket. At least one such contact pin and / or such a contact socket are inserted into an insulating body and, together with this, form a component of the heavy-duty connector.

According to the invention, the crimp contact is at least partially rotationally symmetrical or has at least one or more regions with a cylindrical or at least rotationally symmetrical outer contour, because it can thereby be arranged in a form-fitting manner in through bores or corresponding, likewise rotationally symmetrical through openings of the insulating body.

According to the invention, aluminum is used as the material for the crimp area of the crimp contact due to its easy deformability. This is particularly advantageous for crimping an aluminum conductor, in particular an aluminum stranded conductor, because there is no electrical corrosion and in particular no intermetallic phase in the relevant area despite the inevitable contact with oxygen.

The crimping area has a cavity with a cable entry opening to accommodate the aluminum stranded conductor.

According to the invention, an additional through hole is then drilled in the cavity and an internal thread is cut into this through opening.

According to the invention, such a mandrel, which has a matching external thread and a point adjoining it, can be screwed with its point first into the cavity, preferably in the direction of the cable insertion opening, i.e. against the insertion direction of the stranded conductor.

As a result, the strands of the previously inserted aluminum stranded conductor are pressed from the inside against the crimping area. According to the invention, the crimp contact has an additional internal thread within its crimp area. The stranded conductor is then pressed from the inside against this additional internal thread, the additional internal thread holding the stranded wires due to the increased frictional force. Furthermore, the oxide layer of the aluminum strands is broken up. Because of this and the pressure against each other, the transverse conductivity of the stranded conductor increases. This reduces the contact resistance between the stranded conductor and the crimp contact. Even after crimping, the use of the mandrel improves the conductivity over the long term, especially if the mandrel is preferably made of aluminum or some other electrically conductive material, for example a copper alloy, thereby increasing the contact area of the crimp contact with respect to the stranded conductor.

1. 1.) dass die Oxydschicht der Aluminiumlitzen aufgebrochen wird, und
2. 2.) dass der Litzenleiter entgegen seiner Einführrichtung mit besonders guter Reibwirkung im Hohlraum gehalten ist, aber dass andererseits
3. 3.) die Litzen nicht beschädigt werden. Zum dritten Punkt ist es weiterhin besonders vorteilhaft, wenn die reale Tiefe des abgeflachten Gewindes kleiner ist als der Durchmesser der Litzen, so dass das Gewinde die Litzen nicht durchtrennen kann.

According to the invention, the inner radius of the cylindrical cavity is larger than the theoretical inner radius of the additional internal thread cut into it, so that the additional internal thread protruding into the cavity is flattened. This is particularly advantageous because on the one hand two desired effects of the additional internal thread are retained, namely

1. 1.) that the oxide layer of the aluminum strands is broken, and
2. 2.) that the stranded conductor is held in the cavity against its insertion direction with a particularly good friction effect, but that on the other hand
3. 3.) the strands are not damaged. With regard to the third point, it is also particularly advantageous if the real depth of the flattened thread is smaller than the diameter of the strands, so that the thread cannot cut through the strands.

Because of its stability and its good electrical conductivity, copper is used according to the invention as the material for the contact area. In an advantageous embodiment, the contact area is additionally at least partially coated, for example silver-plated or gold-plated, and thus permanently protected against corrosion. Furthermore, a permanently low-resistance plug connection with other copper contacts and above with corresponding copper lines is thereby advantageously also possible, since the problematic transition between copper and aluminum is laid according to the invention in the interior of the crimp contact.

It is particularly advantageous that the crimping area, which is made of aluminum, is connected to the contact area, which is made of copper, by means of a friction welding process, because in this way the occurrence of electrical corrosion is prevented. After all, the contact surface is located inside the contact and does not come into contact with oxygen in this way. As a result, good conductivity is also sustainable, i.e. also over a long period of time.

Furthermore, the welding, in particular the friction welding, ensures a particularly stable connection, so that the crimp contact is also mechanically stable.

According to the second aspect of the invention, the use of cylindrical copper and aluminum blanks, which are attached to one another in the axial direction, according to the invention by friction welding, be welded. For the friction welding process, rotation welding appears to be sensible at first. The crimping area can advantageously also be connected to the contact area by vibration welding. In practice, a combination of rotation welding and vibration welding has proven to be particularly advantageous, since pure rotation welding has the disadvantage that the inner areas of the contact surface experience less friction than the outer areas, so that the elements at least in the contact area have a central so-called " Blind hole "would have to have. With somewhat more complex vibration welding, however, all areas experience the same frictional energy, so that the inner areas of the contact surface can also be welded. When combined, the advantages of both processes can complement each other.

The contact area can be made into a pin or socket contact by turning and drilling, and the cavity with the cable insertion opening can be drilled into the crimping area. According to the invention, the additional internal thread, which serves to increase the frictional force acting on the stranded conductor, is cut into the cavity.

Embodiment

Fig. 1a,b

einen Querschnitt und eine perspektivische Darstellung eines als Stiftkontakt ausgebildeten Crimpkontaktes;

Fig. 2a,b

einen Querschnitt und eine perspektivische Darstellung eines als Buchsenkontakt ausgebildeten Crimpkontaktes;

Fig. 3a,b

einen Querschnitt und eine perspektivische Darstellung des Stiftkontakts mit einem Innengewinde;

Fig. 3c

eine vergrößerte Darstellung des Innengewindes;

Fig. 4a,b

einen Querschnitt und eine perspektivische Darstellung des Buchsenkontakts mit einem Innengewinde;

Fig. 4c

eine vergrößerte Darstellung des Innengewindes;

Fig. 5a,b

ein 3D-Querschnitt des Stift- und Buchsenkontaktes mit dem zusätzlichen Innengewinde;

Fig. 6a,b

ein 3D-Querschnitt des Stift- und Buchsenkontaktes mit dem zusätzlichen Innengewinde und einem Dorn;

Fig. 7

einen Schwerlaststeckverbinder in einer Explosionsdarstellung.

An embodiment of the invention is shown in the drawings and is explained in more detail below. Show it:

Fig. 1a, b

a cross section and a perspective illustration of a crimp contact designed as a pin contact;

Fig. 2a, b

a cross section and a perspective illustration of a crimp contact designed as a socket contact;

Fig. 3a, b

a cross section and a perspective view of the pin contact with an internal thread;

Figure 3c

an enlarged view of the internal thread;

Figures 4a, b

a cross section and a perspective view of the socket contact with an internal thread;

Figure 4c

an enlarged view of the internal thread;

Fig. 5a, b

a 3D cross-section of the pin and socket contact with the additional internal thread;

Fig. 6a, b

a 3D cross-section of the pin and socket contact with the additional internal thread and a mandrel;

Fig. 7

a heavy duty connector in an exploded view.

The figures contain partially simplified, schematic representations. In some cases, identical reference symbols are used for identical, but possibly not identical elements. Different views of the same elements could be scaled differently.

The Fig. 1a shows a cross section and the Figure 1b shows a perspective view of a first crimp contact designed as a pin contact 1. The pin contact 1 has a first crimping area 11 and a first contact area 12, which are in contact with one another at a first transition area 10, for example by being welded to one another, in particular by a friction welding process. For this purpose, for example, two cylindrical blanks, one of which is made of copper and the other of aluminum, are joined to one another in the axial direction and, for example, are welded to one another by rotation welding and / or vibration welding. By turning and drilling, the first contact area 12 made of copper can be given a contact pin 121 in subsequent work steps, so that this crimp contact is a pin contact 1.

A first cavity 111 can be drilled into the first crimping area 11 made of aluminum. The first crimping area 11 thus has a first cable insertion opening 110 at its free-standing end adjacent to the cavity.

The Fig.2a shows a cross section and the Figure 2b shows a perspective view of a second crimp contact designed as a socket contact 2. The socket contact 2 has a second crimping area 21 and a second contact area 22, which are in contact with one another at a second transition area 20, for example by being welded to one another, in particular by a friction welding process. For this purpose, for example, two cylindrical blanks, one of which is made of copper and the other of aluminum, can be joined to one another in the axial direction and welded to one another, for example by rotation welding and / or vibration welding. By turning and drilling, the second contact area 22, which is made of copper, can be given a contact socket 221 in subsequent work steps, so that this crimp contact is a socket contact 2. Naturally, the bushing 221 has a bushing cavity 2211, which is also preferably created by drilling.

A cavity 211 can also be drilled into the second crimping area 21 made of aluminum. The second crimping area 21 as a result, has a second cable insertion opening 210 at its free-standing end adjacent to the second cavity 211.

The Figures 3a and 3b represent in a comparable manner the pin contact 1 in a modified version, in which the pin contact 1 additionally has a first through-opening 101, which has a cylindrical shape to contain a mandrel 113 (not shown here) (shown in FIG Figure 6a ) to be able to record. Furthermore, the modified pin contact 1 has a pin cavity 1211 which is connected to the first cavity 111 via the first cylindrical through-opening 101. During production, the first through opening 101 is preferably produced by drilling, so that the first through opening 101 is a through hole. Furthermore, an internal thread 103 can be cut into the first through opening 101 so that the mandrel 113, which has a matching external thread 2132, can be screwed into the first through opening 101 and above it into the first cavity 111.

Furthermore, in this modified embodiment, the first crimping area 11 has a first additional internal thread 112 in its first cavity 111, which is cut into the first crimping area 11 from the inside when the pin contact 1 is produced. This first additional internal thread 112 is used to hold a stranded conductor inserted into the first cavity 111 in it by means of an increased frictional force, even if the mandrel 113 is screwed into the first cavity 111 in the direction of the first cable insertion opening 110, i.e. against the direction of insertion of the stranded conductor becomes.

An advantageous embodiment of the first additional internal thread 112 is shown in FIG Figure 3c shown enlarged. It is obvious that the theoretical inside diameter D _{T of} the first additional internal thread 112 is smaller than the real inside diameter D _{R of} the first cavity 111. The real course of this internal thread 112 is shown by the hatched area. On the other hand, the non-hatched area indicates the theoretical course that a theoretical internal thread with the theoretical thread depth T _T and the theoretical thread internal diameter D _T would have. The real cavity inside diameter D _R , however, is greater than the theoretical thread inside diameter D _T , which is used as a measure for the internal thread to be cut into it. As a result, this internal thread 112 has a real thread depth T _R which is smaller than the theoretical thread depth T _T and the real course of the thread 112 is flattened more than usual.

In other words, during production, only the outer part of the theoretical internal thread is cut into the first crimping area 11 and the actually existing additional internal thread 112 thus formed has a particularly flattened shape.

The Figures 4a and 4b represent the socket contact 2 in a comparable manner, which has been modified to include a mandrel 213 (shown in FIG Figure 6b ) to be able to record. For this purpose, the socket cavity 2211 is connected to the second cavity 211 via a second cylindrical through opening 201. During production, this second through opening 201 is preferably produced by drilling, so that the second through opening 201 is a through hole. A second additional internal thread 203 can also be cut into the second through opening 201 so that the mandrel 213, which has a matching external thread 2132, can be screwed into the second through opening 201 and above it into the second cavity 211.

Furthermore, the second crimping area 21 in the second cavity 211 has a second additional internal thread 212 which is cut into the crimping area 21 of the socket contact 2 from the inside during manufacture. This second additional internal thread 212 serves to hold a stranded conductor inserted into the second cavity 211 in it by means of an increased frictional force, even if the mandrel 213 is screwed into the second cavity 211 in the direction of the second cable insertion opening 210, i.e. against the direction of insertion of the stranded conductor becomes.

An advantageous embodiment of the second additional internal thread 212 is shown in FIG Figure 4c shown enlarged. The real course of this internal thread 212 is shown by the hatched area. On the other hand, the non-hatched area indicates the further theoretical course that a theoretical internal thread with the theoretical thread depth T _T and the theoretical thread internal diameter D _T would have. The inside diameter of the cavity D _R is accordingly greater than the theoretical inside thread diameter D _T , which, however, is used as a measure for the inside thread to be cut. As a result, this internal thread 212 has a real thread depth T _R which is smaller than the theoretical thread depth T _T and the real course of the thread 212 is flattened more than usual.

In other words, only the outer part of the theoretical internal thread is cut into the second crimping area 21 during production and the actually existing, additional internal thread 212 thus formed thus has a particularly flattened shape.

In the Figures 5a and 5b the pin contact 1 and the socket contact 2 with the respective cylindrical through opening 101, 201 are placed opposite one another in a sectional 3D illustration.

The Figures 6a and 6b show the pin contact 1 and the socket contact 2 with the respective through-opening 101, 201 and an associated first and second mandrel 113, 213. Each of the through-openings 101, 201 has an associated internal thread 103, 203 The mandrel 113, 213 each has a matching external thread 1132, 2132 with which it is screwed into the respective through opening 101, 201. Furthermore, the mandrel 113, 213 can have a screw head 1131, 2131 which enables it to be screwed in from the pin or socket cavity 1211, 2211.

The Fig. 7 shows a complete heavy-duty connector in an exploded view. A pin contact 1 is shown as an example. But it could just as well be a socket contact 2.

Furthermore, an insulating body 3 is shown, which is provided to accommodate the pin contact 1. This insulating body 3 can in turn be fastened in the connector housing 4 via fastening elements 31.

List of reference symbols

1

Pin contact

10

first transition area

101

first through opening

103

inner thread

11

first crimping area

110

first cable entry opening

111

first cavity

112

first additional internal thread

12

first contact area

121

Contact pin

1211

Pen cavity

113

first thorn

1131

Screw head of the first mandrel

1132

External thread of the mandrel

2

Socket contact

20th

second transition area

201

second through opening

203

inner thread

21st

second crimping area

210

second cable entry opening

211

second cavity

212

second additional internal thread

22nd

second contact area

221

Contact socket

2211

Socket cavity

213

second thorn

2131

Screw head of the second mandrel

2132

External thread of the second mandrel

3

Insulating body

31

Fasteners

4th

Connector housing

D _R

Real inner diameter of the first / second cavity

D _T

Theoretical inside diameter of the additional internal thread

T _R

Theoretical depth of the further internal thread

T _T

Real depth of the additional internal thread

Claims (9)

1. Crimp contact (1, 2) for a heavy load plug connector, wherein the crimp contact (1, 2) is embodied at least in regions in a rotationally symmetrical manner, wherein the corresponding symmetrical axis extends in the plugging direction,
   wherein the crimp contact (1, 2) comprises a crimp region (11, 21) that is embodied from aluminum or an aluminum alloy,
   wherein the crimp contact (1, 2) comprises a contact region (12, 22) that adjoins the crimp region (11, 21), said contact region being embodied from copper or a copper alloy, wherein the crimp region (11, 21) is welded to the contact region (12, 22), wherein the crimp contact (1, 2) comprises in its crimp region (11, 21) a cylindrical hollow chamber (111, 211) having a cable insertion opening (110, 210) for receiving an aluminum stranded conductor, characterized in that the crimp contact (1, 2) comprises in its cylindrical hollow chamber (111, 211) an additional inner thread (112, 212), wherein the actual inner diameter (D_R) of the cylindrical hollow chamber (111, 211) is greater than the theoretical inner diameter (D_T) of the additional inner thread (112, 212) so that the additional inner thread (112, 212) is flattened off, wherein the crimp contact (1, 2) comprises within its hollow chamber (111, 211) a spike (113, 213) that points in the direction of the cable insertion opening (110, 210), wherein the crimp contact (1, 2) comprises a through-going opening (101, 201) having an inner thread (103, 203) that is tailored to said through-going opening so that the spike (113, 213) can be screwed by way of the through-going opening (101, 201) into the hollow chamber (111, 211).
2. Crimp Contact (1, 2) as claimed in claim 1, characterized in that the spike (113, 213) comprises a screw head (1131, 2131), by way of example a slot or a cross slot so that said spike can be screwed with the aid of a screwdriver into the hollow chamber (111, 211).
3. Crimp Contact (1, 2) as claimed in any one of the preceding claims, characterized in that the surface of the contact region (12, 22) is at least in part coated with silver.
4. A heavy load plug connector comprising a plug connector housing (4), an insulating body (3) and at least one crimp contact (1, 2) as claimed in one of the preceding claims.
5. A method for producing a crimp contact according to claim 3, wherein the method comprises the following steps:

   1) welding together a cylindrical copper rod and a cylindrical aluminum rod by means of frictional welding to form a common cylindrical rod having an aluminum part and a copper part,

   2) producing by means of turning and/or drilling an aluminum part a crimp region (11, 21) having a hollow chamber (111, 211) for receiving an aluminum stranded conductor and producing the contact region (12, 22) from the copper part, wherein the hollow chamber (111, 211) is drilled with an actual inner diameter (D_R) in the crimp region (11, 21), wherein the additional inner thread (112, 212) is cut with a theoretical inner diameter (D_T) in the crimp region (111, 211) on the hollow chamber side, wherein the theoretical inner diameter (D_T) of the additional inner thread (112, 212) is smaller than the actual diameter (D_R) of the hollow chamber (111, 211), wherein
   an additional through-going hole (101, 201) can be subsequently drilled in the crimp contact (1, 2) to the hollow chamber (111, 211)and an inner thread (103, 203) can be cut in said through-going opening (101, 201), so that the spike (113, 213) can be screwed into the hollow chamber (111, 211) through the through-going hole (191, 301).

   3) coating the surface of the contact region (12, 22) at least in part with silver.
6. The method as claimed in claim 5, wherein the frictional welding in the first method step comprises rotational welding and/or vibration welding.
7. A method for using a crimp contact (1, 2) as calimed in one of the claims 1 to 3, wherein

   A.) initially a stranded conductor is inserted through the cable insertion opening (110, 210) into a cylindrical hollow chamber (111, 211) of a crimp region (11, 21) of the crimp contact (1, 2) and wherein in a later method step the

   B.) spike (113, 213) is screwed into the hollow chamber (111, 211) of the crimp region (11, 21) opposite the direction of insertion of the stranded conductor and wherein in a later method step

   C.) the crimp region (11, 21) is pressed together using a crimping tool
8. The method as claimed in claim 7, wherein the stranded conductor is held when screwing the spike (113, 213) by means of the additional inner thread (112, 212) of the hollow chamber (111, 211) using a particularly strong frictional force in the hollow chamber (111, 211).
9. The method as claimed in any one of the claims 8 to 9, wherein
   the stranded wires of the stranded conductor are pressed together by means of screwing in the spike (113, 213) and are pressed from the interior against the crimp region (11, 21), and that as a consequence furthermore oxide layers of the stranded conductors are broken open, as a result of which the cross conductivity is increased.

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