DE102011018353A1 - Welding sleeve with contact part - Google Patents

Abstract

Connection of an electrical cable 4 formed from a plurality of wires or strands 4b to a connecting part 6, with a support sleeve 2 enclosing an end region 4c of the cable 4 for receiving an end face 4b of the cable 4, so that the wires or strands 4b in the support sleeve 2 are held, the end face 4d of the cable 4 formed from the individual wires or strands 4b being welded to the connecting part 6 by means of an at least end-face weld 9. A particularly cost-effective connection to contact parts is possible if the connecting part 6 has a rivet shaft 8 on the side opposite the weld seam 9.

Description

The subject matter relates to a connection of an electrical cable formed from a plurality of wires or strands with a connection part, in particular for the electrical system of a motor vehicle, with a support sleeve enclosing an end region of the cable for receiving a terminal end side of the cable, so that the wires or strands in the support sleeve are held, wherein the end of the cable formed from the individual wires or strands is welded to the connection part by means of an at least frontal weld. The subject matter further relates to a method of making a connection between a cable, a connector and a contact member.

The connection of electrical cables with connection parts is commonplace in the automotive industry in particular. However, the cost pressure is enormous, so that the supplier industry is always on the lookout for process-reliable, durable, but cost-effective connection technologies.

From the European patent EP 1 032 077 B1 For example, a connection of an aluminum cable with a terminal part, which may be formed of copper, known. Here it is described that the end of the aluminum cable, in particular the stripped end of the aluminum cable, is pressed by means of a sleeve, so that the strands of the cable are pressed together. The thus-pressed end of the cable is connected to a connection part by a friction welding process.

The technology described there was a breakthrough in the connection of aluminum cables with connection parts, since for the first time the possibility was created to connect aluminum process-reliable and permanently with other joining partners, in particular copper or brass. The sleeve ensures that the strands of the aluminum cable do not splice during the welding process. This ensures that a good intermetallic connection is created between the end faces of the strands and the connection part. This is an important prerequisite for a permanent, electrically good conductive connection.

A disadvantage of the method described in said EP-letter and the said compound, however, is that the connecting part offers little leeway in terms of its geometry. Although the connection part described there permits a reliable, permanent and electrically good connection between an aluminum cable and a contact part formed from another metal, the connection part is subject to geometric limitations. Due to the increased use of aluminum cables, it has become necessary to connect a wide variety of geometries and types of contact parts with the aluminum cable, while maintaining the process reliability and durability of the connection in the known manner.

For this reason, the object was the object to provide a connection of a cable with a connector available, which is on the one hand process reliable, on the other hand, however, allows a high degree of geometric flexibility for a contact part at the same time high clock rates.

This object is achieved by a compound according to claim 1. It is objectively proposed that the connection part has a rivet shank via which a contact part can be riveted to the connection part. It has been recognized that a connection part can be welded particularly easily to the end face of the cable and / or to the end face of the support sleeve. However, the connection part must satisfy geometric requirements in order to optimize the welding process.

Since the connection part itself is preferably made of copper or an alloy thereof, it can then be contacted with a contact part in a particularly simple manner when the contact part is riveted to the connection part. To allow the riveting, the connection part has a rivet shank. A rivet shank is preferably formed of a ductile metal, which is z. B. by means of a mandrel so that it lays collar-like around an opening of a contact part and thus forms a positive, preferably also frictional connection with the connection part and the contact part.

A particularly simple contacting of the connection part to the support sleeve or the front side of the cable is possible if a rotary friction welding method is used. This friction welding process has been tried and tested many times and has proven to be particularly reliable in the past. The resulting friction-welded joint is durable and thus particularly well suited for use in the automotive industry. In order to enable rotary friction welding, the joining partners are preferably rotationally symmetrical. In particular, the connecting part, which is to be welded to the wires, is rotationally symmetrical to be clamped in a corresponding welding tool. Since the connection part is rotated around the wires or the cable at very high speeds during the welding process, imbalances in the area of the connection part are to be avoided. Therefore, the connection part is particularly advantageous rotationally symmetrical, so that it can be rotated at high speeds.

According to an advantageous embodiment, it is proposed that the connection part is welded to the end face of the cable formed by the individual wires or strands by means of rotary friction welding. As already explained, rotary friction welding is a particularly reliable welding method which has proven itself millions of times over. Therefore, the connecting part, as proposed, also welded by means of rotational friction welding to the cable and / or the front side of the sleeve.

For a contacting of a contact part on the connection part must be prevented from forming contact corrosion at the contact point. Also, the contact resistance between the connection part and the contact part must be low. For this reason, the connecting part is preferably formed from a non-ferrous metal, in particular copper or alloys thereof. Here, the connection part may also be brass and / or a galvanic coating, for. As nickel, have. Such a connection part offers an enormously high degree of flexibility with regard to the connection of a further contact part, since in particular a copper connection part has particularly good electrical properties and therefore produces electrical contact with a contact part in a particularly simple manner. Preferably, however, the cable is formed of aluminum. Thus, the connection part forms the "bridge" between the cable formed of aluminum and the contact part formed of another metal. The intermetallic connection between aluminum and copper in the region of the connection between the cable and the connection part is particularly good in rotary friction welding, since the weld seam can be well protected against environmental influences.

According to an advantageous embodiment, it is proposed that the rivet shank is arranged substantially parallel to a longitudinal axis of the cable at the connecting part. When the connector is brought to the cable, it is substantially aligned with the longitudinal axis of the cable. As soon as the connecting part is aligned with the longitudinal axis of the cable, the rivet shank advantageously runs parallel to the longitudinal axis of the cable. In particular, the rivet shank is substantially coaxial with the longitudinal axis of the cable, that is, the axis of the rivet shank substantially coincides with the longitudinal axis of the cable. The rivet shank is preferably cylindrical or hollow cylindrical shaped and the axis of rotation of such a cylinder is parallel to the longitudinal axis of the cable. Preferably, the axis of the rivet shank is co-linear with the longitudinal axis of the cable, that is, the axes travel along a single straight line. The longitudinal axis of the cable is preferably the longitudinal axis in the region of the support sleeve. The longitudinal axis of the cable in the region of the support sleeve corresponds to the axis in the extension direction of the cable in the region of the support sleeve. Also, the longitudinal axis of the cable may be the axis of rotation during rotary friction welding.

According to an advantageous embodiment, as already indicated, it is proposed that the connection part is riveted to a contact part. For this purpose, the rivet shank of the connecting part is used as a rivet, which is riveted to the contact part. By riveting at least a positive connection between the connection part and contact part is made. This positive connection is particularly electrically conductive when the connection part and contact part made of copper or alloys thereof is formed. In such a compound contact corrosion is not a problem, since the connection part and contact part can be formed of the same metal. Also, contact part and / or connection part may be galvanically coated, for. B. nickeled or tinned.

According to an advantageous embodiment, it is proposed that the contact part is pushed over the rivet shank of the connection part and that the rivet shank is at least partially formed into a closing head. It is proposed that first the connection part is welded to the support sleeve and / or the cable. Subsequently, the contact part is pushed with an opening over the rivet shank. Finally, by means of a bolt, a mandrel or other mechanical shaping tool, the rivet shank is reshaped in such a way that, in the form of a closing head, it engages around the opening of the contact part in the shape of a closing head, thus producing positive locking between the connecting part and the contact part.

It is particularly proposed that the closing head engages behind an opening in the contact part. Preferably, the closing head forms a circumferential, outwardly facing collar, which has a diameter which is greater than the diameter of the opening in the contact part and thus engages behind the opening and produces the positive connection.

According to an advantageous embodiment, it is proposed that the rivet shank of the connecting part is hollow cylindrical. As a result, a particularly simple riveting of the rivet shank to the contact part is possible because then the walls of the rivet sheep must be bent only outwards to allow the positive connection in the form of a rivet to the contact part. Bending outwards can be realized, for example, with a mandrel engaging in the rivet shank.

According to an advantageous embodiment, it is proposed that the contact part a Sheet metal part is. This is particularly advantageous because a bent sheet metal part can have any geometry. In particular, a bent sheet metal part may be L-shaped and thus form a connection console for an electrical connection. The shape and size of the connection console is almost arbitrarily shapeable, without cost advantages of the previously described methods and the connection described above must be abandoned. Since the bent sheet metal part only has to have an opening in the region of the rivet, which is adapted to the rivet, the rest of the bent sheet metal part can be adapted to larger requirements. It is proposed that the contact part has an electrical contact. This can be for example a bore or a bolt. It is also possible that the contact part is formed as crimp. Furthermore, the contact part can have a plug face, which can be contacted with any desired plug. The shape of the contact part is independent of the connection between aluminum and copper used in the region of the connection part. As a result, a multiplicity of different contact geometries and plug geometries can be realized with only a single connection technology in a particularly simple manner and particularly cost-effectively.

An end region of the cable is in particular the region of the cable which is stripped. The end face of the cable is preferably formed by the ends of the wires or strands. Preferably, the cable has been cut or cut so that a flat as possible end side of the cable is formed. The strands thus end preferably in a plane, in which case a tolerance range of +/- 1 to 2 mm is possible.

The connection between the support sleeve, the cable and the connection part is advantageously realized via the weld. This is advantageously a friction weld, a Rotationsreibschweißnaht, a resistance weld, a laser weld or ultrasonic welding. These welding methods are all suitable for connecting a cable to a connection part.

In particular, these methods are suitable for connecting a cable to a connection part. In particular, these methods are suitable for connecting a cable formed from aluminum or an aluminum alloy with a connecting part formed from a non-ferrous metal, in particular copper, in particular a copper alloy. However, it is also possible that the connecting part is also made of aluminum or steel or stainless steel. The connection part is advantageously made of a formable material which is conductive, for. Brass.

A particularly good weld can be realized in that the end face of the cable is flush with one end of the support sleeve. In this case, not only the end face of the cable or the end faces of the wires or strands can be connected to the connection part during welding, but at the same time also the end face of the support sleeve.

As already explained, the cable can be made of aluminum or an aluminum alloy. In addition, the connection part may be formed from a conductive, preferably formable material. Here are in particular non-ferrous metals (so-called non-ferrous metals) such as copper or copper alloys such as brass or bronze, or steel or stainless steel.

It is also proposed that the cable is stripped in the region of the support sleeve. In this case, the stripped portion of the cable or the stripped end of the cable can be inserted into the support sleeve and then pressed with the support sleeve. For this purpose, the support sleeve may be slotted, so that when pressing the slot is closed and the diameter of the support sleeve is reduced. As a result, a pressing of the strands is facilitated.

Another aspect is a method according to claim 12. It is proposed that initially a support sleeve is arranged at an end region of a cable. The support sleeve serves to hold the end face of the cable, in particular wires and strands of the cable to hold. Preferably, after the arrangement of the support sleeve, this is pressed against the cable, so that the wires or strands of the cable are pressed. In this case, the sleeve preferably has a longitudinal slot, which serves to reduce the sleeve when pressing its inner diameter and thus compresses the wires or strands of the cable. The sleeve is preferably made of aluminum or aluminum alloys or of copper or copper alloys.

After the sleeve has been pushed onto the cable and pressed with the cable, it is proposed that at least the ends of the wires or strands are welded to the connector part. For this purpose, a connection surface of the connection part is applied to the front side of the wires or strands and welded to them. Preferably, a rotary friction welding method is used here.

Finally, a contact part is riveted to the connection part via a rivet shank. The contact part is preferably made of the same metal as the connecting part, so that no contact corrosion occurs. In addition, the connection part as also the contact part, preferably made of copper or alloys thereof. The ensured by the riveting positive connection also ensures good electrical contact between the contact part and connector and thus between the contact part and cable. Preferably, the riveting is performed so that in addition to the positive connection and a frictional connection is formed.

The riveting may advantageously be a radial riveting or wobble riveting. In this case, the force is applied to the rivet not exclusively parallel to the longitudinal axis of the rivet.

By riveting the contact part on the rivet shank of the connection part, it is possible to freely choose the axial position of the contact part, since the axial position of the contact part to the connection part is fixed only after riveting.

The features described above, in particular also the features of the dependent claims, may also be inventive in combination with one another or independently while circumventing all or some of the features of the independent claims.

The article will be explained in more detail with reference to drawings showing an exemplary embodiments.

In the figures shows:

1 a sectional view of a cable with a support sleeve;

2 a further sectional view of a cable with a support sleeve;

3a a sectional view of a cable with a support sleeve and a welded thereto connector part;

3b a sectional view of a connection after 3a together with a contact part;

4a a sectional view of a cable with a support sleeve and another connection part;

4b a sectional view of a compound according to 4a with a contact part;

5 a flowchart of an objective method;

6a -F views of the connection in various stages of manufacture according to embodiments.

1 shows a support sleeve 2 in a sectional view. The support sleeve 2 is preferably round and formed of aluminum, copper or alloys thereof. Furthermore, in the 1 an electrical cable 4 , In particular, a battery cable of a motor vehicle, in particular for connecting a battery with a starter or a generator as well as another electrical line of a motor vehicle, but also shown a cable of a wind turbine. As you can see, this is the cable 4 with an isolation 4a overdrawn. The cable 4 is in an end area 4c from the isolation 4a free, so the strands 4b of the cable 4 exposed.

The exposed strands 4b of the cable 4 are in the support sleeve 2 inserted. It can be seen that the front side 2a the support sleeve 2 flush with the front end 4d of the cable 4 is.

The support sleeve 2 is preferably pressed so that the strands 4b within the support sleeve 2 close together.

2 shows a further embodiment of a connection of a support sleeve 2 with a cable 4 , In the 2 it can be seen that the end area 4c the support sleeve 2 not completely filled out. The frontal end 4d the strands 4b is here inside the sleeve 2 so that these are not flush with the front 2a the support sleeve 2 are. Both the arrangement after 1 as well as the arrangement 2 is suitable for connection to a connector as claimed.

3a shows the cable 4 with the support sleeve 2 according to the 1 , The support sleeve 2 is about the strands 4b of the cable 4 placed and pressed so that the strands 4b pressed together. To the support sleeve 2 or strands 4b welded is the connection part 6 , It can be seen that the connection part has a first circumferential collar 6b or a circumferential groove and at one end a rivet shank 8a , In the arrangement of the sleeve 2 according to 2a becomes the connection part 6 at least partially in the sleeve 2 inserted.

The connection part 6 has a first pad that faces the weld 9 shows. The surface opposite this connection surface is with the rivet shank 8th fitted.

A friction welding tool may be the connecting part 8th on the collar 6b grab and over the collar 6b a pressure in the direction of the cable 4 exercise while the connector part 6 around the support sleeve 2 and the cable 4 is rotated around. Also, the collar can 6b be replaced by a groove, preferably circumferentially. The friction welding tool can engage in such a groove and thus set the connecting part in rotation. Preferably, the axis of rotation is corresponding to the longitudinal axis 5 of the cable 4 , When rotating the connection part 6 melts the front page 2a the support sleeve 3 as well as the frontal end 4d the strands 4b on and it creates the weld 9 in which an intermetallic connection between the strands 4b and the connector 6 is formed. The weld 9 preferably extends along the strands 4b or the front end 4d the strands 4b , The weld 9 but can also be on the frontal end 2a the support sleeve 2 extend.

When connected to a support sleeve 2 and a cable 4 according to 2 can the connection part 6 have a corresponding to the support sleeve pot into the support sleeve 2 could be inserted. Then the weld could be at least along the front side 4d the strands 4b be formed.

The longitudinal axis 5 of the cable 4 preferably also corresponds to the axis of rotation of the connecting part 6 and thus also the axis of rotation of the rivet shank 8a , The rivet shaft 8a is in the 3a formed as a hollow cylinder.

In the 3b is at the connection part 6 a contact part 10 arranged. Both the connection part 6 as well as the contact part 10 are preferably formed of copper or alloys thereof.

In the connection part 10 is an opening 10a provided on the rivet shank 8a is postponed after the connection part 6 with the strands 4b over the weld 9 was welded.

Subsequently, the rivet shank 8a be bent so that a closing head 8b Forming collar-shaped outward opening 10a of the contact part 10 engages behind.

About the closing head 8b becomes a positive connection between the connection part 6 and contact part 10 educated. At the contact part 10 can be a bore 12 be provided for screwing an electrical contact to the contact part 10 can serve.

It can be seen that the contact part 10 is formed as a sheet metal part and thus is particularly inexpensive to produce.

4a shows a further embodiment, which is substantially the embodiment according to 3a corresponds, here the rivet shank 8a is formed as a solid cylinder. Again, the axis of rotation of the rivet shaft 8a according to the longitudinal axis 5 of the cable 4 and is colinear with this. After the connection part 6 over the weld 9 with the cable 4 welded, can, how 4b is shown, a contact part 10 with his mouth 10a over the rivet 8a be pushed. Subsequently, the rivet shank 8a be mechanically transformed so that a closing head 8b is formed. This can be done with a high pressure on the rivet shank 8a , preferably parallel to the longitudinal axis 5 , preferably in the direction of the cable 4 be pressed so that the rivet shank 8a to the rivet head 8b deformed. Again, the rivet shank 8b the opening 10a of the contact part 10 and thus forms at least one positive locking, with corresponding pressure on the rivet shank 8a even a positive connection between the connection part 6 and contact part 10 ,

It can be seen that on the contact part 10 a plug 12b is formed as an electrical contact. In that the contact part 10 no consideration for the connection between the cable 4 and the connector 6 must take the contact part 10 be shaped arbitrarily and, for example, different plugs 12b Support crimp connectors or other connector faces. Also, the contact part 10 be formed as a bolt or threaded bolt.

5 shows the sequence of an objective procedure. In a first step 20 will, as in the 6 shown, the support sleeve 2 on the strands 4b of the cable 4 postponed.

Subsequently, in one step 22 the support sleeve 2 so around the strands 4b of the cable 4 pressed that the strands are pressed together. The frontal end 2a the sleeve 2 is plane parallel to the front end 4d the strands 4b of the cable 4 ,

In a further step 24 can have a pad 6a of the connection part 6 with the support sleeve 2 be aligned so that the axis of rotation of the connection part 6 with the longitudinal axis 5 of the cable 4 is colinear.

In a subsequent step 26 is the connecting part by means of a friction welding process 6 on the cable 4 or strands 4b and / or the support sleeve 2 welded. This can be done via the collar 6b a compressive force on the support sleeve 2 and the front ends 4d the strands 4b be exercised while the connector part 6 around the longitudinal axis 5 of the cable 4 is rotated. This creates an intermetallic connection between the strands of the cable 4 and the connector 6 ,

In a subsequent step 28 can the contact part with its opening 10a over the rivet 8a be pushed. The axial Positioning of the contact part 6 in relation to the longitudinal axis 5 of the cable 4 can be specified.

Finally, in one step 30 the riveting 8a be deformed so that a closing head 8b collar-shaped at least pointing outwards around the opening 10a of the connection part 10 puts, so that a positive connection between connector 6 and contact part 10 forms.

The subject method enable the use of the rotary friction welding technique already widely tested in the automotive industry for the connection of an aluminum cable with a connector made of copper. Standardized friction welding adapters can be used, which can be manufactured, for example, as turned parts, forgings, die-castings, or extrusions. Such Reibschweißadapter can as connecting parts 6 serve.

With the help of existing friction welding systems, the friction welding adapters (connecting parts) can be welded to the cables in a particularly easy way. Particularly high speeds are possible because the Reibschweißadapter are usually rotationally symmetric.

By using the rivet shank, it is possible to arrange different cable shoe geometries in the form of the contact parts directly on the connecting parts (friction welding adapter) and when arranging them directly to the correct orientation to attach to the line. In this case, in particular, the contact part can be rotated around the rivet shank in order to define the orientation of the contact part on the line. The transition between the aluminum and the copper in the region of the connection part can preferably be protected against environmental influences by means of a heat-shrinkable tube. The subject method as well as the subject compound provides a cost effective way to electrically connect various contact parts in a particularly simple manner with a cable made of aluminum.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 1032077 B1 [0003]

Claims (12)

Connection of an electrical cable formed from a plurality of wires or strands with a connection part, in particular for the electrical system of a motor vehicle, comprising a support sleeve enclosing an end region of the cable for receiving an end-side end side of the cable so that the wires or strands are held in the support sleeve are, wherein - the end of the cable formed from the individual wires or strands is welded to the connection part by means of an at least frontal weld, characterized in that - the connection part has a rivet shank on the opposite side of the weld. Connection according to claim 1, characterized in that the connecting part is rotationally symmetrical. A compound according to claim 1 or 2, characterized in that the connecting part is welded to the formed of the individual wires or strands end face of the cable by means of rotary friction welding. A compound according to claim 1 or 2, characterized in that the connecting part is made of a non-ferrous metal, in particular copper or alloys thereof, or of stainless steel and / or that the cable is made of aluminum or alloys thereof. Connection according to one of the preceding claims, characterized in that the rivet shank is arranged substantially parallel to a longitudinal axis of the cable to the connecting part, in particular that the rivet shank is substantially coaxial and / or collinear with the longitudinal axis of the cable Connection according to one of the preceding claims, characterized in that the connection part is riveted to a contact part. Connection according to one of the preceding claims, characterized in that the contact part is pushed over the rivet shank of the connecting part and the rivet shank is at least partially formed into a closing head. Connection according to one of the preceding claims, characterized in that the closing head engages behind an opening in the contact part. Connection according to one of the preceding claims, characterized in that the rivet shank of the connecting part is hollow cylindrical. Connection according to one of the preceding claims, characterized in that the contact part is a bent sheet metal part. Connection according to one of the preceding claims, characterized in that the contact part has an electrical contact. Method for connecting an electrical cable formed from a plurality of wires or strands with a connection part, in particular for the electrical system of a motor vehicle Arranging a support sleeve enclosing an end region of the cable at an end-side end side of the cable so that the wires or strands are held in the support sleeve, Welding the end face of the cable formed from the individual wires or strands with the connecting part, characterized by - Riveting of the connection part on the opposite side of the weld with a contact part by means of a rivet shank.

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