WO2022200009A1 - Cable-sealing arrangement and method for establishing a connection between a main cable and a branch cable in a cable-sealing arrangement - Google Patents

Abstract

A cable-sealing arrangement having an at least two-part housing with an upper part and a lower part, and at least one opening formed as a cable-entry point in the housing, wherein the upper part and the lower part each form one part of the openings, characterized in that, when the housing is in the joined state, abutting joining surfaces of the upper part and lower part have been welded to one another.

Description

Cable seal and method of making a connection between a main cable and a branch cable in a cable seal

The subject relates to a cable seal and a method for making a connection between a main cable and a branch cable in such a cable seal.

In the field of automotive engineering, electrical wiring is safety-relevant. Since vehicles are generally exposed to changing environmental conditions, such as rain, spray water, road salt, severe temperature fluctuations and the like, electrical connections are always sources of error, particularly with regard to leakage currents, short circuits and/or corrosion. Contact corrosion can be promoted by the voltage applied to the cable, particularly in the case of battery cables, which may also be permanently connected to the battery plus potential.

Connections between two electrical lines are usually implemented using a cable lug and/or appropriate screw connections. It is important here that the connection point is protected against the ingress of moisture. Nowadays, this is usually implemented using a shrink tube with an inner adhesive, which is pulled over the connection point and then shrunk. However, such a heat-shrink tubing, particularly in connection with silicone-coated cables, is problematic with regard to longitudinal water that creeps between the heat-shrink tubing and the cable insulation. A complete seal is hardly achievable here.

The so-called fording depth is also a relevant criterion, particularly for battery cables or other high-voltage applications in the automotive industry. Vehicles can only be submerged in water to a certain depth. This depth is called the wading depth. Laying battery cables under the floor leads to that the cables may be below the fording depth of the vehicle. In particular, there is a risk that immersing underground electrical lines in water could permanently damage them. Underfloor laying and/or laying outdoors is always a problem with regard to moisture penetration. Due to the electrification of the drive train, however, an underfloor installation and/or an installation in the outside area, in particular outside the passenger compartment, is increasingly being carried out. Here, and in particular in the case of high-voltage applications, in particular in the case of voltages from 48V, in particular in the case of voltages of over 300V, the connection between the cables must be specially secured against the ingress of moisture. In particular, longitudinal water must be prevented from causing leakage currents or short circuits.

In particular, the sealing of center taps, where a branch cable branches off in the middle of a main cable, the isolation can only be achieved with an expensive Y-

Shrink tubing is possible and the manufacturing effort for threading the cable into one is enormous. In addition, the sealing effect, particularly depending on the insulation material of the cable, is sometimes insufficient, especially in the case of silicone-coated cables. The permissible ambient temperature for the use of such systems is also limited by the melting temperature of the inner adhesive.

In addition to the expensive shrink tubing, there is the option of protecting the connection from water with the help of a housing. However, the sealing of the housing at the cable mounts is always problematic.

The object of the object was therefore to protect the connection between at least two electrical lines within a motor vehicle against moisture. This problem is solved by a cable seal according to claim 1. A cable seal may also be referred to as a seal case, housing, enclosure or the like.

First, a two-part housing is proposed. Such a housing is formed from at least one upper part and at least one lower part. The terms above and below describe the relation of the two parts to each other. A top may also be referred to as a first part and a bottom may be referred to as a second part.

The upper part and lower part can each be shell-shaped and form the housing when joined. In the assembled state, the connection between two cables or a cable and a connecting bolt or another connecting part is formed within the housing. A cable can be a connection cable or a main cable or vice versa. Main and drop cables are terms to linguistically distinguish these two cables from each other. The cables themselves can be essentially the same, identical or similar in structure to one another. Whenever a branch cable is mentioned, a connecting part, connecting bolt, connecting piece, connecting lug, connecting part or the like is also meant. What these parts have in common is that they can be electrically connected to the main cable and at least one electrically conductive part, preferably encased in an insulating material, is routed out of the housing. Whenever a main cable is mentioned, a connecting part, connecting bolt, connecting piece, connecting lug, connecting part or the like is also meant. What these parts have in common is that they can be electrically connected to the connecting cable at a center tap and at least two electrically conductive parts, preferably encased in an insulating material, are routed out of the housing.

The two-part design of the housing, in particular an upper part and a lower part, has the advantage that the housing can be arranged at any point along the cable harness, ie also in the area of a center tap. It can be at any A center tap can be realized along the main cable and this can be sealed by the housing in question.

The advantage of the two-part housing is that after the main cable has been connected to the branch cable, this connection can be inserted into the lower/upper part, then the second part of the housing is placed and the housing closed in this way is sealed. Time-consuming threading of the connection into a Y-shrink tubing is no longer necessary.

In the housing is at least one opening formed as a cable entry. The opening is used to introduce the cable into the housing. Preferably, the opening is formed in an area between the top and bottom. When the housing is in the assembled state, the opening can be partly in the upper part and partly in the lower part. For example, if the upper part is placed on the lower part, the side walls of the upper part and lower part are in contact with one another. In one area of a wall, the upper part and the lower part each have a recess which forms part of the opening when the housing is joined. The cable is routed out of or into the housing in the area of this opening.

In order to seal the housing, it is now proposed that when the housing is in the joined state, joining edges of the upper part and lower part that rest against one another are welded to one another. The upper and lower parts are particularly moisture-tight, but preferably also gas-tight, welded. When joined, the upper and lower parts lie directly against one another with their joining edges. The materials of the upper and lower parts can be melted and thus joined together, preferably by means of laser welding, but also by means of ultrasonic welding, hot gas welding or the like. The materials are in particular plastics, in particular thermoplastics. Preference is given to using PA6 or PA6.6 with an optional glass fiber liner between 15-30% by weight or by volume. The cable seal in question is particularly suitable for a cable branch on a center tap of a main cable. A main cable can be stripped at a center tap. The main cable with an insulating jacket extends on both sides of this stripped area. The material of the insulating sheath of the main cable and/or the branch cable can be a silicone. The material of the insulating jacket can also be PVC.

The sealing ring will preferably be a particularly soft and temperature-resistant material. Silicone or rubber are preferably used here. The isolation, on the other hand, can vary. Silicone, PVC or PUR are typical here. EPDM, XLPE/XLPO, PA11/PA12 are also conceivable. When using an insulating jacket made of silicone, the sealing ring is preferably also made of silicone.

In the stripped area, the bare metal of the cable core is mechanically and electrically connected to a branch cable, preferably with its bare metal at a likewise stripped end. Connection can in particular be force-fitting, form-fitting and/or cohesive. Connection can in particular include crimping, soldering and/or welding. The branch cable can in particular be formed as a splice.

The two cable ends of the main cable emanating from the stripped center tap protrude from two openings in the housing and the end of at least one branch cable, which extends away from the center tap, protrudes from at least one third opening in the housing. More than 2 cables can also be welded to form a "star". The background would be, for example, that different insulation materials are used in one line harness. This means that a modular design that meets the requirements is possible.

Main cable and branch cable can be connected to each other in a first step. Here, for example, an area can first be stripped in the middle of the main cable. Also, one end of a branch cable can be stripped will. A stripped end of a branch cable can be placed on top of the exposed bare metal of the main cable after stripping. Main and branch cables can be connected to each other with their metallic strands. This is possible, for example, by means of ultrasonic welding, laser welding, resistance welding, friction welding or the like.

Main cables and branch cables can be formed from solid material both as stranded conductors with a large number of strands and as solid conductors with only one strand. In particular, the main cable can also be formed as a flat conductor rail, from which the branch cable branches off. The main cable can also have a round conductor cross-section or, in the case of a flat conductor rail, an angular conductor cross-section. The branch cable can preferably have a round conductor cross-section.

After the cables have been joined, they can be inserted into the upper or lower part and the cable strands can be inserted into the recesses provided for this purpose in the side walls. The corresponding upper/lower part can then be put on and arranged with the recesses over the cable strands. The openings formed by the upper and lower parts enclose the cable strands, in particular the insulation jackets of the cables.

According to one exemplary embodiment, it is proposed that the cables are arranged in an insulated manner in the area of a respective opening on the housing. In this case, insulation takes place in such a way that a sealing ring is arranged between the insulation jacket of the cable and the housing. An inner almond surface of the sealing ring bears against the insulation jacket of the cable and an outer shell surface of the sealing ring bears against the inner wall of the housing in the area of the opening.

It makes sense to first put two sealing rings on the main cable and to arrange them on both sides of the center tap. The isolation of the center tap can be removed before or after. Onto the also stripped end of the branch cable another sealing ring can be pushed on. This can also be done before or after stripping. When removing the insulation, the insulating jacket can be cut open, for example, using a laser or a knife.

The sealing ring is preferably made of a plastic that is softer than the material of the housing and can be referred to as a soft component. The sealing ring is in particular made of an elastomer, EPDM, silicone or rubber.

The sealing ring can, for example, have a core made of a hard component and outer lateral surfaces made of the soft component. The soft component can enclose the core all around. It is also possible for the sealing ring to be formed from a hard component and a soft component along its longitudinal axis. However, the sealing ring can also preferably be formed only from the soft component.

According to one exemplary embodiment, the hard component can be glued or welded to the housing. Thus, between the inner surface of the opening and the hard component, a materially bonded joining zone can be created that is sealed.

However, the soft component preferably bears circumferentially against the insulation of the cable and circumferentially against an inner lateral surface of the opening. Due to an elastic deformation of the sealing ring, it has a sealing effect against longitudinal water.

The cable is movably mounted in the opening. In order to prevent leaks from occurring as a result of axial movements of the cable, it is proposed that the sealing ring be formed in a lamellar manner on at least the inner lateral surface, but preferably also on the outer lateral surface. In this case, at least two, but preferably more, axially spaced, radially projecting, preferably completely circumferential lamellae can be provided. One slat on one The outer lateral surface is formed from a radially further outwardly protruding area and a radially less far outwardly protruding area. A lamella on an inner lateral surface is formed from a region that projects radially further inwards and a region that projects radially less far inwards.

In a longitudinal section, the lamellae can be triangular, truncated, arcuate or the like. Areas that protrude further radially outwards can alternate with areas that protrude further radially inwards.

According to one exemplary embodiment, it is proposed that the sealing ring be in the form of a bellows. This enables the sealing ring to compensate for movements along the longitudinal axis of the cable while maintaining its tightness.

According to one exemplary embodiment, it is proposed that the sealing ring be oversized in relation to the opening. Thus, in the joining state, the sealing ring between the housing and the cable is elastically compressed in the radial direction. The inner diameter of the sealing ring is preferably smaller than the outer diameter of the cable with the insulation jacket. The outer diameter of the sealing ring is preferably larger than the inner diameter of the opening in the assembled state of the housing. The sealing ring is thus pushed onto the cable and stretched elastically in the process. When inserting the sealing ring into the opening and closing the housing, the sealing ring is preferably elastically compressed. As a result, the sealing ring is elastically compressed in the assembled state.

According to one exemplary embodiment, it is proposed that the joining surfaces that abut one another are congruent to one another. The upper and lower parts are joined and connected to one another at their joining surfaces. The joining surfaces can be flat or lie flat against one another. However, it is also possible for the joining surfaces to be congruent to one another, so that they have projections and/or recesses that engage in one another. In this case, in particular web-shaped joining surfaces, in particular interlocking folds, can be provided. It is also possible that the Joining surfaces are formed on the one hand groove-shaped and on the other hand web-shaped and can be plugged into each other.

Welding can then take place in particular in the area of the interlocking surfaces. The adjacent side walls of the upper and lower parts preferably run along one plane. Due to interlocking joining surfaces, the upper and lower parts also preferably touch on such surfaces that run parallel or at an angle to such a plane, but are not perpendicular to it. A welding process is preferably initiated at these contacting joining surfaces. In particular, the upper and lower parts are joined to one another in a materially bonded manner at these planes, which run parallel or at an angle, but not at right angles, to the plane of the side walls. However, it is also possible that, cumulatively or alternatively, the joining surfaces are welded to one another on the surfaces that run perpendicular to the plane just mentioned.

In this case, it is particularly preferred that the joining edges that rest against one another are laser-welded to one another.

In this context, it is particularly preferred if the materials of the upper and lower parts have different opacities from one another. In this case, it is particularly preferred if the housing part that is further to the outside, starting from the joining surface, has a lower opacity than the housing part that is further to the inside, starting from the joining surface. A laser can then radiate through the housing part that is further outside, starting from the joining surface, down to the joining surface of the housing part that is further inside and heat the materials at this transition between the two housing parts and weld them together.

According to one exemplary embodiment, it is proposed that the sealing ring be mounted between two stops that are axially spaced apart from one another and are arranged on the inner lateral surface of the housing and run at least partially around the circumference. An attack can be formed by a projection pointing radially inwards in the region of the opening. The projection can be at least partially circumferential. Two axially spaced stops can axially support the sealing ring in the opening. Here, the stops form a clear width that is smaller than the outer circumference of the sealing ring. It is preferred if a stop is arranged both in the upper part and in the lower part, with these respective stops forming a partially circumferential stop in the assembled state. In the assembled state, the sealing ring cannot slip axially beyond one of the at least partially circumferential stops. The sealing ring is preferably axially compressed between the stops. The axial extent of the sealing ring is preferably at least partially greater than the axial distance between the at least partially circumferential stops, so that when the sealing ring is inserted between the stops, it is axially compressed.

According to one embodiment, the hard component is radially surrounded on both sides by the soft component. The hard component projects beyond the soft components in the axial direction. In the assembled state, these hard components protrude outwards through the opening. In the overhanging area, the hard component encompasses a projection forming the opening on an outer lateral surface. This encompassing area of the hard component can latch with locking means on the outer circumference of the projection forming the opening, in particular relative to the axial direction.

Another aspect is a method according to claim 15.

An axial direction is defined by a direction of insertion of the cable into the opening. The axial direction can thus be understood in particular as a direction that runs transversely, preferably essentially at right angles, to the outer surface in which the opening is formed. The axial direction is in particular parallel to the surface normal of the surface in which the opening is formed when the housing is joined. A radial direction runs at right angles to the axial direction. The radial direction is preferably the direction in which the opening extends. The radial direction preferably extends outwardly from a center point of the opening. The opening can be oval, rectangular, rectangular, circular, or the like. The opening is adapted in particular to the cable cross section, which can be rectangular in the case of a flat cable or round in the case of a round cable.

The object is explained in more detail below with reference to a drawing showing exemplary embodiments. Show in the drawing:

1 shows a center tap as a splice;

2a-d different embodiments of sealing rings;

Fig. 3 shows the arrangement of a sealing ring in a cable housing according to one

embodiment;

4 shows the arrangement of a sealing ring in a housing according to an exemplary embodiment;

Fig. 5 shows the arrangement of a sealing ring in a housing according to one

embodiment; 6a, b shows a cross section through a connection of housing parts according to an embodiment;

7 shows a view of a housing according to an embodiment. Fig. 1 shows a connection between two cables. A main cable 2 is connected to a branch cable 4 . The two cables 2, 4 are formed from a cable core 2a, 4a and an insulating jacket 2b, 4b.

The cable cores 2a, 4a are made of a metallic material, in particular copper or a copper alloy and aluminum or an aluminum alloy. The main cable 2 is stripped in a central area 6, i.e. the insulating jacket 2b is removed from the cable core 2a. This can be done in particular by removing the insulating jacket 2b using a laser, in particular by cutting open the insulating jacket 2b using a laser. Starting from the area 6, the cable 2b extends with two cable ends.

The cable core 4a of the branch cable 4 is connected to the cable core 2a in the area 6 . In particular, there is a material connection. In particular, soldering or welding is possible here. However, it is also possible for a clamping connection, in particular in the form of a crimp, to be provided. The connection is preferably formed in a materially bonded manner by means of welding, in particular by means of friction welding, preferably by means of ultrasonic welding or by means of resistance welding. The cable cores 2a, 4a are thus mechanically and/or electrically connected to one another.

At the branch cable 4, the cable core 4a is exposed at a cable end. The other end of the cable 4 extends from the area 6 away. A connection shown here between a main cable 2 and a branch cable 4 can also be called a splice.

A sealing ring 8 can be provided on the cable 2 at each of the two cable ends at a distance from the region 6 . A sealing ring 8 can be provided on the cable 4 at a distance from the region 6 . The sealing ring 8 will be described in more detail below. During production, two sealing rings 8 can be pushed onto the main cable 2 at a distance from the area 6 . The insulating jacket 2b can be removed in the region 6 beforehand or afterwards. Then a stripped cable end of the branch cable 4 is connected in the area 6 with its cable core 4a to the cable core 2a in the manner described above. A sealing ring 8 can be pushed onto the branch cable 4 beforehand or afterwards. A connection is formed between a main cable 2 and a branch cable 4, a sealing ring 8 being pushed onto the respective insulation jackets 2b, 4b at a distance from the connection at the outgoing cable ends. Such a connection between two cables can be protected against moisture as will be described below.

A sealing ring 8 to be pushed onto the insulating jackets 2b, 4b is shown in FIGS. 2a-d by way of example. A cross section and a longitudinal section through a sealing ring 8 are shown in each case.

In FIG. 2a it can be seen in cross section that the sealing ring 8 has an outer circumference 8a and an inner clear width 8b. The inner clear width 8b is geometrically similar to the cross-sectional profile of the respective cable 2, 4, in particular in terms of its profile, and is preferably round or rectangular.

A longitudinal section through the sealing ring 8 shows that it has lamellae 12 spaced apart from one another along the axial axis 10 in the region of its inner lateral surface. The lamellae 12 are formed by areas that project radially further inwards and radially less far inwards. Radial is one

Direction perpendicular to the longitudinal axis 10. The slats 12 are preferably circumferential to a central axis that runs along the longitudinal axis 10.

When the sealing ring 8 is slid on, the lamellae 12 rest on the insulating jacket 2b with their radially further inwardly projecting areas. For sealing against the housing, it is preferred that, in addition to the lamellae 12, lamellae 14 are also provided on the outer circumference 8a, as shown in FIG. 2b. The lamellae 14 can be formed in the same way as the lamellae 12 and have areas that project radially further outwards and radially less far outwards. In the installed state, the areas that protrude further radially outwards rest against the inner wall surfaces of the opening of the housing.

2c shows a sealing ring 8 made from a soft component 8' and a hard component 8''. The sealing rings 8 according to FIGS. 2a and b, which are formed only from the soft component 8′, are additionally supplemented by a hard component 8″ according to FIGS. 2c and d. According to FIG. 2c, the hard component 8″ is provided on the outer circumference of the sealing ring 8 . In the longitudinal section according to FIG. 2c it can be seen that the lamellae 12, as described above, are provided on an inner circumference.

A ring made of a hard component 8" bears circumferentially on the outer circumference 8a of the sealing ring 8. A peripheral projection in the manner of a welding lug can be provided on this ring. In the joined state, this projection can bear on the inner lateral surface of the housing and there in a The hard component 8 is preferably made of the same material as a top or bottom side of a housing.

Fig. 2d shows a further exemplary embodiment of a sealing ring 8. In this sealing ring, the hard component 8" is led out of an axial end face of the sealing ring 8. The hard component 8" preferably encompasses the soft component 8 on the outer circumference 8a of the sealing ring 8. The lamellae 12, 14 are provided according to FIG. 2b. The part of the hard component 8" with a U-shaped cross-section encloses the outer housing wall in the assembled state in order to fix the sealing ring 8 in the housing.

7a shows a lower part 16 and an upper part 18 of a housing. It can be seen that the lower part 16 and the upper part 18 are formed in the shape of a half-shell. In the housing parts 16, 18 recesses are provided, into which a cable can be inserted. The recesses open into openings 20, which are only partially formed by upper part 18 and lower part 16 in the non-joined state and only join together to form an entire opening 20 in the joined state.

A connection according to FIG. 1 can be inserted into a lower part 16, as shown in FIG. 7b. The sealing rings 8 are positioned directly in the area of the openings 20 . Then the upper part 18 is placed on the lower part 16 .

7c shows how the upper part 18 and lower part 16 are joined to form a housing 22. FIG.

Upper part 18 and lower part 16 are connected to one another in a materially bonded manner along a weld seam 24 . From the openings 20, the cables 2, 4 protrude with their cable ends. The openings 20 are shaped in such a way that they are sealed together with the sealing ring 8, as will be shown below.

FIG. 3 shows a plan view of a lower part 16, whereby the description can also apply to the upper part 18, at least in part.

First, it can be seen that the lower part 16 is shell-shaped and in the area of the openings 20 a sealing ring 8 is inserted in each case. The sealing ring 8 rests with its lamellae 14 on the inner lateral surface of the lower part 16 . A hard component 8 is provided on the sealing ring 8 protruding beyond an end face. In longitudinal section, the hard component 8 is U-shaped in such a way that it encompasses the outer lateral surface of the lower part 16 . In the assembled state, the upper part 18 is the lower part 16 placed. In the process, the lamellae 14 are compressed radially inwards. The hard component 8" is then pushed onto the opening in such a way that it encompasses both the upper part and the lower part in the area of the opening 20 and fixes them to one another. The cables are not shown in FIG. 3, but are in contact with their insulating jackets 2b, 4b the inner slats 12 and deform them elastically radially outwards.

The sealing ring 8 is compressed in the assembled state and seals the opening 20 both on the inside of the housing and on the cable sheath.

A joining surface 24 is provided on the lower part 16 . A joining surface 24 complementary thereto is provided on the upper part 18 .

6a, b show exemplary embodiments of such guide joint surfaces 24. In FIG. 6a it can be seen that the upper part 18 and lower part 16 have folds 26, 28 which engage in one another. The upper part 18 is formed from a material that has a lower opacity than the material of the lower part 16. This allows a laser beam 30 to be guided through the material of the upper part 18 up to the joining surface 24. The laser beam 30 radiates through the upper part 18 and heats the materials of the lower part 16 and the upper part 18 at the joining surface 24 so that they melt and are connected to one another after cooling.

The same applies to FIG. 6b, but here the joining surfaces 24 are formed by tongue and groove. Here, too, a laser beam 30 can be guided through the less opaque material of either the upper part 18 or the lower part 16 to the joining surface 24 and cause the materials to melt there. This welding process welds the half shells together.

During welding, the two housing halves 16, 18 are also moved towards one another under pressure, so that the materials are connected when they are melted. Preferably, upper part 18 and lower part 16 each have a circumferential jetty up. These webs lie on top of one another in the parting plane. The second material of the inner housing part is then heated through the material of the outer housing part and welded under pressure Stops 32a, 32b is fixed axially in the lower shell 16. The sealing ring 8 can also be compressed axially by the stops 32a, b. Here, too, the sealing ring 8 provides a seal on the one hand on the inner surface of the housing and on the other hand on the insulating jackets in the manner described.

FIG. 5 shows a further exemplary embodiment in which a sealing ring 8 according to FIG. 2c is used. In contrast to the previous exemplary embodiments, the sealing of the sealing ring 8 on the inside of the housing is realized via the radially outwardly projecting welding lug. Here, the welding tab can be welded to the inner surface of the lower shell 16 and the upper shell 18 . In particular, a laser beam is brought up to the welding surface and welding melts the materials so that they are firmly bonded to one another after cooling.

The exemplary embodiments according to FIGS. 3-5 differ only in the type of sealing rings 8. The insertion of the cable and the connection of upper part 18 and lower part 16 to one another in the manner shown in FIGS. 6a and b, as well as in this also generally described ways, but does not differ.

reference list

2 main cables 4 branch cables 2a, 4a cable core

2, 4b insulating jacket 6 area 8 seal 8' soft component 8" hard component

8a outer circumference 8b clear width 10 longitudinal axis 12, 14 slats 16 lower part

18 upper part 20 opening 22 housing 24 joint surface 26 fold

30 laser beam 32a,b stop

Claims

P atentClaims 1. Cable seal with - an at least two-part housing with an upper part and a lower part, - at least one opening formed in the housing as a cable entry, - the upper part and the lower part each forming part of the openings, characterized in that - when the housing is joined to one another adjacent joint surfaces of upper and lower part are welded together. 2. Cable seal according to Claim 1, characterized in that at least one branch cable, in particular as a splice, is connected to a stripped center tap of a main cable inside the housing, and in that the cable ends of the main cable extending from the center tap are routed out of two openings in the housing and that the at least one branch cable is routed out of the housing through at least a third opening. 3. Cable seal according to claim 1 or 2, characterized in that - the cables are insulated in the region of a respective opening. 4. Cable seal according to claim 3, characterized in - that at least one of the openings formed from at least one soft component sealing ring circumferentially on the insulation of the respective cable and circumferentially on an inner surface of the respective opening. 5. Cable seal according to claim 4, characterized in that - at the opening, a sealing ring has at least two axially spaced circumferential lamellae on its inner lateral surface and/or on its outer lateral surface. 6. Cable seal according to one of claims 4 or 5, characterized in that - that the sealing ring is bellows-shaped. 7. Cable seal according to one of the preceding claims, characterized in that the abutting joining surfaces are congruent to one another and are formed in particular in the form of webs, in particular in the form of webs and grooves, or as interlocking folds. 8. Cable seal according to one of the preceding claims, characterized in that - the abutting joint surfaces are laser-welded. 9. Cable seal according to one of the preceding claims, characterized in that the upper part and the lower part are made of plastics with different opacities. 10. Cable seal according to one of the preceding claims 3 to 9, characterized in that - That in the joining state of the sealing ring between the housing and the cable is compressed in the radial direction. 11. Cable seal according to one of the preceding claims 3 to 10, characterized in that the sealing ring is mounted between two axially spaced stops which are arranged on the inner lateral surface of the housing and run at least partially around the opening. 12. Cable seal according to one of the preceding claims 3 to 11, characterized in that the sealing ring is formed from a soft component and a hard component. 13. Cable seal according to claim 12, characterized in that the hard component is formed on an outer circumference of the sealing ring with a radially outwardly pointing projection and the projection is welded to the upper part and the lower part. 14. Cable seal according to one of the preceding claims 12 or 13, characterized in that the hard component extends in the axial direction beyond the opening into a sealing section. 15. A method for producing a connection between a main cable and a branch cable in a cable seal according to any one of the preceding claims, comprising - providing the main cable with a stripped center tap, - connecting a stripped end of the branch cable to the center tap, - Slide a sealing ring onto the insulation of the main cable on both sides of the center tap, - Slide a sealing ring onto the insulation of the main cable on both sides of the center tap, - sliding a sealing ring onto the insulation of the branch cable, - inserting the cables together with the sealing rings in the lower part, - placing the upper part on the lower part in such a way that the cables are surrounded by the upper part and lower part and the sealing rings are in the area of the openings between the upper part and the lower part are jammed and compressed, - welding of upper part and lower part together along the joint surfaces.