EP3155694B1 - Device for contacting an electrical conductor - Google Patents

Description

The invention relates to a device for contacting an electrical conductor according to the preamble of patent claim 1.

US Pat. No. 3,386,069 already discloses a device for contacting an electrical conductor. The device has isolation parts that define a receiving space into which cables to be contacted are inserted with their end portions. A pack of loosely woven, resilient cloth is packed in the receiving space under tension. The material of this cloth is copper, bronze or aluminum.

• eine Einrichtung mit einem doppelwandigen Schlauch, der kontinuierlich umläuft entlang einem langgestreckten Element, wobei relative Gleitbewegung erfolgen zwischen den beiden Wänden der Doppelwand im Wesentlichen ohne relative Gleitbewegung zwischen einer Wand neben dem Element und dem Element; und
• ein Dichtungsmaterial, wobei das Dichtungsmaterial einen Klebstoff, einen Mastix, ein Gel, eine gelartige Zusammensetzung oder einen Mörtel aufweist; und
• einen elektrischen Leiter, der als Abschirmung geeignet ist.

EP 0 209 399 A2 discloses a kit of parts comprising:

• a device having a double-walled hose continuously circulating along an elongate member, relative sliding movement being made between the two walls of the double wall substantially without relative sliding movement between a wall adjacent to the member and the member; and
• a sealing material, wherein the sealing material comprises an adhesive, a mastic, a gel, a gel-like composition or a mortar; and
• an electrical conductor that is suitable as a shield.

In cable ladders with large cross sections of, for example, more than 100 mm ² - in particular more than 1000 mm ² - to reduce losses in power transmission in medium and high voltage cables, conductor designs formed from individual wires are increasingly used in which insulating materials between the individual wires or between made of individual wires constructed segments, or in which the individual wires are coated with insulating materials. Such ladder constructions minimize the undesirable skins and proximity effects, in particular in the case of large cross sections, in order to increase the transmission power of the cable or to make do with smaller cross sections.

In this case, the conductors are preferably divided into several segments, which are assembled with bands or other insulating layers to cross-sectionally circular conductors. Within the segments, the individual wires, which are also optionally insulated from one another, are twisted and drawn through a forming die, so that the current is subsequently routed in the individual wires again and again following the wire run in the longitudinal direction of the cable from the outer layer into the interior of the conductor. The segments are usually wound in the outside with ribbons and are electrically isolated from each other. Such cable ladder constructions are for example from US 1,904,162 A known and are also referred to as MILLIKEN type.

The economic advantage of this design in terms of material cost optimization is offset by the disadvantage that the conductor preparation during installation is complex and time-consuming to ensure that the internal wires of the conductor can be contacted at the junction and thus contribute to power transmission. As a rule, the insulating materials must be completely removed from the conductor assembly. The individual wires must be freed from insulating materials, so bent and brushed, and then the individual wires again manually combined by means of hose clamps and pressing tools in a nearly circular shape of the diameter of the original conductor so that they can be inserted into the connecting element and sufficiently compressed and held by this. The effectiveness of these measures depends on the care of the installation.

From the EP 2 226 899 A1 a device is known in which as a contact medium, a wedge-shaped tip is radially screwed into a tubular clamp body, characterized in contact-bearing contact with the front ends of the two on opposite sides in the terminal body axially inserted conductor can be brought, and thereby an electrical connection between the Both ladders can be produced.

The invention has for its object to provide a device for contacting an electrical conductor, in particular a stranded conductor of a power supply cable, and a connection or connection device with such a device, which overcome the disadvantages of the prior art. In one embodiment, in particular the assembly of such devices and thus the production of connection or connection devices according to the invention should be simplified while still ensuring a high contact reliability and a high current carrying capacity.

This object is achieved by the device defined in claim 1 and by the specific in claim 9 connection or connection device. Particular embodiments of the invention are defined in the subclaims.

According to the invention, the contact bodies have, at least in sections, a spherical surface, which is preferably spherical, and the device has at least one acting on the contact medium Force introduction element, with which the contact force in the contact medium can be introduced. Through such shaped contact body for the electrical contacting particularly advantageous power transmission between the contact bodies and / or the conductor to be contacted and / or the connecting body is possible. In particular, the use of balls as a contact body is advantageous because an isotropic force distribution can be achieved in a simple manner.

According to the invention, the device has a force introduction element acting on the contact medium and in particular the contact bodies, with which the contact force can be introduced into the contact medium. The necessary contact force can be generated, for example by means of one or more screwed into the deformation body pressure screws after the introduction of the contact body in the limited by the deformation of the body and the conductor to be contacted receiving space.

In one embodiment, the device according to the invention for contacting an electrical conductor, in particular a cable conductor of a power supply cable, a connecting body, in which the conductor to be contacted can be used with its front end; the device also has the contact medium, with which the front end of the conductor is electrically contacted and which has a plurality of electrically conductive contact bodies, of which at least one part can be brought into electrically contacting contact with the front end of the conductor, preferably to the entire front end of the conductor; by the contact body, the contact force on adjacent contact body and / or the conductor to be contacted and / or the connection body transferable, in particular from a force introduction point of the connecting body, for example, a screwed into the connecting body pressure screw, to the front surface of the conductor to be contacted. An inventive Device can be used for electrically connecting two or more conductors as well as for connecting one or more conductors to an electrical equipment. The connecting body may be in one piece, whereby, for example, the recording of the acting clamping and contact forces is simplified, or be multi-part, whereby, for example, the assembly of the device is simplified, for example, already laid cables during installation no longer have to be moved in the longitudinal direction, but the Cable ends on the junction or the other end of the cable can swivel in, which is particularly advantageous for large conductor cross-sections. The connecting body may be sleeve-shaped at least in sections so that the conductor to be contacted or the conductors to be connected to one another can be inserted or inserted into the sleeve-shaped section. At least a part and preferably all contact bodies can have an identical shape and preferably also an identical size.

Particular advantages of the invention when contacting mehrdrähtiger head, for example, cable ladders of the type MILLIKEN. The present invention decisively improves the level of functioning of the connections known from the prior art by not or at least not, as hitherto customary, utilizing the peripheral surface at the conductor end for current transmission, but also or even exclusively the front side of the conductor, preferably the entire end face of the leader. In addition, this design allows the use of relatively short-built connection systems that require less installation space and thus allow the use of smaller, easier to install and cheaper to produce insulating systems in sets.

The end face of the ladder grows geometrically proportionally with its cross section. The front side is in all known different conductor designs, the only surface that metallic in a particularly simple manner blank is available. Thus, the cables are usually shortened during installation to the appropriate length, preferably sawn off. All other surfaces of the conductor to be contacted must be prepared in a separate operation more or less consuming.

In the device according to the invention unlike the conventional pressing and screwing at the nip no transverse force must be exerted on the conductor to produce the electrical transverse conductivity between the individual wires and the connecting body. This is advantageous because such a transverse conductivity is increasingly difficult to achieve for larger cross sections and / or partially insulated conductor designs.

The electrical and mechanical functions of the contact device can be divided into two, spatially possibly also separated or even spaced sections, namely a first section, which is responsible for the current transport and provides a low electrical resistance with short current paths using metallic materials with good thermal conductivity and a second section, which is responsible for mechanical fixation and power transmission, and which provides high mechanical strength and a rugged, site-specific design with sufficient tolerance to deviations between planned and delivered conductor design, thereby ensuring fail-safe and time-saving installation.

Inventive devices can therefore be made very slim and short, since the power supply leads directly from one end of the conductor to the other end of the conductor or to a contact surface. The sleeve-shaped connector body is designed primarily for mechanical stress, which is when using high strength materials with lower wall thicknesses can be fulfilled as usual today. This allows the use of smaller and less expensive insulating body of cable fittings.

In one embodiment of the invention, the contact force is transferable substantially independently of direction to adjacent adjacent contact body and / or the conductor to be contacted and / or the connecting body. As a result, a quasi-hydrostatic pressure and thus power distribution is achieved. This leads to the fact that the electrical contacting of the conductor takes place over a short connecting distance.

In one embodiment of the invention, the electrically conductive contact bodies have an electrically conductive surface coating which, compared to the material of the contact bodies, has a permanently lower contact contact resistance. For example, while the contact bodies may be made of copper or aluminum, the coating may consist of gold or silver, or of tin or zinc, or of an alloy using at least one of these elements. As a result, at high pressure stability of the contact body, a permanently low contact contact resistance to adjacent adjacent contact bodies and / or to the conductor to be contacted, in particular uncoated copper or aluminum conductors, and / or achieved to the connector body.

The thickness of the surface coating may be more than 1 μm and less than 25 μm , in particular more than 2 μm and less than 10 μm , and preferably more than 2.5 μm and less than 6 μm . The size of the contact body, in particular the spherical contact body, on the one hand to be chosen so that they can not penetrate expected cavities or isolierstoffgefüllte interstices at the conductor end faces, and on the other hand to choose so small that a quasi-hydrostatic balance of the contact body at point load is achieved and as possible Each individual wire is contacted on the front side of at least one, preferably of at least two contact bodies. In the case of spherical contact bodies, the ball diameter should be much smaller than the individual wire diameter of the conductor.

In one embodiment of the invention, the contact medium has a pasty and, at room temperature, preferably viscoelastic mass, in which the contact bodies are embedded. This is also advantageous for the installation, since the positioning and metering of the contact body is simplified and the handling of loose contact bodies, in particular of balls, on the installation site is problematic. The mass may allow a homogeneous distribution of the contact bodies, and / or allow a dimensionally stable application of the contact body on the prepared conductor end face, and / or not adhere to the assembly tool when used as intended, and / or prevent oxidation of the electrical contacts, and / or not in remaining voids diffuse and do not react chemically with the known insulating materials, and / or do not alter the electrical properties of a conductor smoothing layer or cable primary insulation.

In one embodiment, the device has a force accumulator acting on the contact medium and in particular the contact bodies, with which the contact force can be permanently maintained. The necessary for the undisturbed operation minimum holding force should be compensated and maintained by a suitable spring accumulator after the disappearance of all set losses and taking into account the operational reversible volume changes due to thermal expansion of the materials. The energy accumulator can also be integrated into the force introduction element. The desired bias can be applied in a simple manner by the installer by tightening the pressure screw (s) and on the applied torque, for example by screws with Tear off heads to be controlled. Alternatively or additionally, indicators may indicate that the springs are sufficiently tensioned. This gives the installer clear feedback that the installation has been carried out correctly and that the connection can thus withstand maintenance-free operation requirements.

In one embodiment, the device has at least one force indicator or at least one signal element, which indicates in each case that the contact medium is sufficiently braced by means of the force or contact memory. Such a display, for example, with signal elements in the form of force indicators simplifies assembly while ensuring a relatively tight tolerances of the contact means.

In one embodiment, the device has a fixing device for fixing the conductor to be contacted to the connecting body, in particular for fixing the axial position of the conductor to be contacted with respect to the connecting body. Above all, the fixing device absorbs forces in the longitudinal direction of the conductor, which act on the conductor from the outside during installation and during operation. The fixing device fixes, for example in a stranded conductor the single wire association at the terminal point in the transverse direction of the conductor, clamps the individual wires on the front side of the prepared conductor ends as possible form-fitting manner and forms a stable counter bearing for standing under the pressure of the contact force contact body.

The invention also relates to a connection and connection device with a device as described above and with a contacted electrical conductor, in particular a stranded cable conductor of a power supply cable, wherein at least a part of the contact body is in electrically contacting system at the front end of the conductor.

This enables in a simple way a permanently safe and large-scale electrical contacting of the conductor.

In one embodiment, at least a part of the contact body has an at least partially curved surface, in particular an at least partially spherical surface, and preferably at least a part of the contact body is spherical. The radius of the curved surface is less than 50% of a narrow side of the front surface of the contacted conductor or the wires of a stranded conductor, in particular less than 40% and preferably less than 25%. This ensures that at least one contact body rests on each individual wire of the conductor.

In one embodiment, the conductor is stranded, and in the front end of the contacted conductor at least one expansion element is used, preferably, a spreading element is inserted centrally in the frontal end of the contacted conductor. As a result, a radial expansion of the conductor is achieved, which is advantageous in order to clamp the conductor pressure-stable at the contact point can. Without the driving of at least one expansion element in the center of the conductor, which is already filled in many ladder constructions with a soft plastic, which must be replaced because of the required pressure stability, would create a kind of vault, the radial load from the outside in the direction of the center Absorbs pressure load in an undesirable manner and dissipates in the circumferential direction. The radially applied clamping force would then not act on the inner wire layers. Due to the widening of the conductor cross section by means of the expansion element, in particular a central pin, the individual wires are no longer adjacent to the adjacent wires and the force acting from outside is now transmitted to the underlying wires and not supported transversely. This makes it possible the clamping force up to act in the center of the conductor and individual wires are fixed more effectively.

The expansion element may be at least partially conical or wedge-shaped. The expansion element may have one or more, preferably detachable without tools sections, so that after a sufficient driving of the expansion element in the conductor, the expansion element on the front side of the conductor is separable, preferably without the remaining part in the conductor protrudes beyond the end face of the conductor.

In order to clamp the individual wires of a stranded conductor in the radially outermost position and to fix sufficiently, for example, distributed on the circumference of the connecting body, radially acting clamping screws can be used. For this purpose, the clamping screws can be arranged at a small distance on the circumference. If necessary, the clamping screws can be arranged in two or more rows in the axial direction one behind the other. Ring cutting or conical surfaces on the heads of the clamping screws are advantageous for a large-area clamping contact of preferably several individual wires.

In order to compensate for the diameter tolerance of the conductors occurring in practice, it is advantageous to achieve an adaptation of the connecting body to the actual conductor diameter. The remaining gap must be smaller than the contact body used to prevent penetration of the contact body in the gap. For example, by conical shaping of the conductor receiving bore and axial displaceability of the contact part, this gap can be sufficiently reduced during installation.

In one embodiment, an annular element is placed at or near the front end of the contacted conductor whose outer diameter is adapted to the receiving space of the connecting body, in particular, the outer diameter of the annular element can substantially correspond to the clear width of the receiving space of the connecting body; Alternatively or additionally, the inner diameter of the annular element may be adapted to the outer diameter of the conductor to be contacted, in particular, the inner diameter of the annular element may substantially correspond to the outer diameter of the conductor to be contacted. As a result, centering of the conductor in the connecting body can be achieved and / or the circumferential contour of the conductor, in particular its roundness, can be secured.

In particular, when the annular element is installed prior to driving the expansion element, it serves as a radial boundary and fixation of the conductor and secures its peripheral contour when subsequently the expansion element is driven in and the conductor assembly therefore tries to expand radially. At the same time the positive connection between the individual wires is reduced in the transverse direction and improved to the annular element. The gap on the outer diameter of the conductor closes, the clamping force for later mechanical fixation of the conductor composite can act through the clamping screws to the center. Several annular elements with different dimensions can be provided, in particular with different inner diameters, so that conductors with different dimensions can also be contacted with a connecting body by selecting a suitable annular element.

When contacting conductor end faces, the following conditions must be taken into account: The sawed end face of a stranded conductor is metallically bare in the case of the manually executed installation, but very undulating and can also be sawed off at an angle to the cable direction; These form deviations occurring during cable preparation can not be defined. The end face that is available for contacting corresponds to the delivered conductor cross-section, which is generally slightly smaller than the nominal cross-section from the data sheet of the cable. The end face to be contacted may consist of individual wires with possibly different diameters; the individual wires may be coated on the wire surface with thin insulating layers and, by compaction during manufacture, may have different cross-sectional shapes that may deviate from the ideal circular shape. The individual wires can not be connected to each other in the transverse direction and can be moved conditionally to each other in the longitudinal and transverse directions; they are held in the longitudinal association only by twisting and positive locking. Individually or in combination, insulating materials in the form of powder, tapes or homogeneous plastic fillings can be present between the individual wires. The insulating materials are usually less pressure stable than the end faces of the wires and therefore deviate under mechanical stress. Relaxation and setting behavior in the case of punctual and / or surface compressive load correspond to the values typical for plastics, far below the characteristic values to be expected with pure metals. Larger gussets between conductor segments and / or centrally inserted waveguide or plastic cords may be present.

Fig. 1

zeigt einen Längsschnitt durch ein erstes Ausführungsbeispiel der Erfindung,

Fig. 2

zeigt einen um 90° um die Längsachse gedrehten Längsschnitt des ersten Ausführungsbeispiels,

Fig. 3

zeigt einen Längsschnitt durch ein zweites Ausführungsbeispiel,

Fig. 4

zeigt einen Längsschnitt durch ein drittes Ausführungsbeispiel,

Fig. 5

zeigt einen Längsschnitt durch ein viertes Ausführungsbeispiel,

Fig. 6

zeigt einen Längsschnitt durch ein fünftes Ausführungsbeispiel,

Fig. 7

zeigt einen Längsschnitt durch ein sechstes Ausführungsbeispiel, und

Fig. 8

zeigt einen Längsschnitt durch ein siebtes Ausführungsbeispiel.

Further advantages, features and details of the invention will become apparent from the subclaims and the following description in which several embodiments are described in detail with reference to the drawings. The features mentioned in the claims and in the description may each be essential to the invention individually or in any desired combination.

Fig. 1

shows a longitudinal section through a first embodiment of the invention,

Fig. 2

shows a rotated by 90 ° about the longitudinal axis longitudinal section of the first embodiment,

Fig. 3

shows a longitudinal section through a second embodiment,

Fig. 4

shows a longitudinal section through a third embodiment,

Fig. 5

shows a longitudinal section through a fourth embodiment,

Fig. 6

shows a longitudinal section through a fifth embodiment,

Fig. 7

shows a longitudinal section through a sixth embodiment, and

Fig. 8

shows a longitudinal section through a seventh embodiment.

The Fig. 1 1 shows a longitudinal section through a first exemplary embodiment of the invention with a device 1 according to the invention for contacting a multi-wire electrical conductor 10, in the present case for connecting the first multi-wire electrical conductor 10 to a second multi-wire electrical conductor 20, which are the cable conductors 10, 20 of a first power supply cable 12 and a second power supply cable 22 acts. The two conductors 10, 20 are in the region of the device 1 coaxial with the longitudinal axis 2 of the device 1. Die Fig. 2 also shows a longitudinal section through the device 1, in which the device 1, however, is rotated by 90 ° about the longitudinal axis 2.

The first embodiment is used to connect cross-section conductor 10, 20 and uses as an external contact system, the tubular connector body 4, which is like a normal press connector left and right on the prepared ends of the conductors 10, 20 is pushed and pressed, for example, with hydraulic tools. Similar to a conventional compression connector, the connection body 4 can be used with appropriate conductivity for power transmission from the contacted on the surface bare conductor wires of the two conductors 10, 20. But because possible insulation layers of the individual wires have not been removed and in multi-layer cables experience shows that only the two outer layers are involved in the current transport, so that alone sufficient electrical contact is made. Therefore, the pressing ensures, above all, that the two ends of the conductors 10, 20 fixed to the connecting body 4 and thus are mechanically stable connected to each other.

Due to the fact that also the front ends 14, 24 of the conductors 10, 20 are clamped radially and can move only slightly or not at all in the longitudinal direction, a receiving space 6 is axially through the two conductors 10, 20 and radially through the connecting body 4 limited, are introduced into the contact body 32, which are embedded in a pasty mass 34 and together with this form the contact medium 30 of the device 1, which is only partially drawn for reasons of clarity.

The contact bodies 32 are formed by balls made of copper, which have a uniform size and are coated with a 3 .mu.m to 5 .mu.m thick layer of tin. The diameter of the balls is more than 10% and less than 100% of the extension of the narrow side of a wire of the conductor 10, 20, in particular more than 15% and less than 90% and preferably more than 20% and less than 85%. The pasty mass 34 may comprise a silicone gel or other paste of suitable viscosity.

After introducing a sufficient amount of the contact medium 30, for example via the two adjoining the receiving space 6 and along the longitudinal axis 2 successively arranged first threaded openings 16 are screwed into these threaded openings 16 as a force introduction element 18 each have a threaded pin or a tear screw and thereby closed the receiving space 6 and set the contact medium 30 under further screwing further.

The device also has two force accumulators 28, each having a package of disc springs 38 and are used on axially opposite sides radially into the connecting body 4, in particular screwed into corresponding second threaded holes 26 and then glued therein. The two force introduction elements 18 are screwed and tightened so far in the connecting body 4 until force indicators in the form of signal elements 36 indicate to the force accumulators 28 that the contact medium 30 is sufficiently braced. The energy storage 28 are sized so that they maintain the minimum required holding force, even if due to thermal load cycles and permanent relaxation losses, the volume between the two conductors 10, 20 should expand or the ends of the two conductors 10, 20 should still move something ,

The FIG. 3 shows a longitudinal section through a second embodiment of the invention with a device 101, in which a one-piece tube is pushed as a connecting body 104 over the ends of the two different or cross-sectionally identical conductors 110, 120. Subsequently, the two conductors 110, 120 are fixed with the axially outermost retaining screws 142 on the connecting body 104, which form part of a fixing device of the device 301; the central part 144 with the force accumulators 128 or spring packs 138 is already installed in the connecting body 104 and fixed there axially and radially in the middle. With a corresponding configuration, part of the current load can flow via the retaining screws 142 and the connecting body 104, but this is not absolutely necessary and therefore permits shorter designs of the device 101. It is advantageous in this exemplary embodiment that all connections Can be tightened with standard tools for fasteners and no special tools are required.

The preferably spherical contact bodies 132 are introduced via the still open holes 116 for the force introduction elements 118 until the receiving space 106 between the conductors 110, 120 is completely filled. The contact force is applied by the force introduction elements 118, which are formed for example by threaded pins and finally screwed into the bores 116 and tightened until no more screw overhang can be seen.

The centering screw 146 in the center of the connecting body 104 fixes the prestressed force accumulators 128 with their packages of cup springs 138. By torque-controlled tightening of the four force introduction elements 118 of the dimension M12, the contact bodies 132 are pressurized and the force accumulators 128 are prestressed.

The connecting body 104 can be formed from a tube or also from connectable half-shells, which can be laid around the conductors 110, 120 and can be clamped to one another and to the conductors 110, 120 by means of a suitable device.

On the two conductors 110, 120, an annular element 148 is placed at its front end, whose outer diameter is adapted to the receiving space 106 of the connecting body 104, in particular substantially equal to the clear width of the receiving space 106 of the connecting body 104, and its inner diameter to the Outer diameter of the conductor to be contacted 110, 120 is adapted, in particular substantially corresponds to the outer diameter of the conductor 110, 120 to be contacted. As a result, the conductors 110, 120 are centered in the connector body 104 and their peripheral contour is secured, preferably circular. The annular elements 148 engage over the front end of the conductor 110, 120 to form an annular and radially inwardly directed web 152 which forms a stop when the annular element 148 is pushed onto the conductor 110, 120.

In the front end of the two conductors 110, 120, a spreader element 150 is used centrally, which has a plurality of sections, of which at least one part is in each case frustoconical and which are preferably separated from each other without tools. Also, the contour of the illustrated longitudinal section through the expansion element 150 is conical, so that the associated conductor 110, 120 is more strongly spread and thus pressed into contact with the inside of the annular member 148, the deeper the spreader 150 driven into the conductor 110, 120 becomes.

The FIG. 4 shows a longitudinal section through a third embodiment of the invention with a device 201, in which the installation is facilitated by the fact that a second part 204b, in particular a second half, of the two-part or multi-part tubular connecting body 204 can be removed from a first part 204a and again can be placed on the first part 204 a and fixed there, for example with a ring, as soon as the connecting body 204 is in the correct position to the conductors 210, 220. It is also possible for both sides of the connecting body 204 to be designed in this way.

For installation, one side of the connecting body 204 is pushed onto the end of the first conductor 210 and fixed there by the retaining screws 242. There may be provided in the axial direction two or more rows of circumferentially preferably equidistantly spaced retaining screws 242, wherein the retaining screws 242 of adjacent rows may be offset in the circumferential direction to each other, so that a plurality and preferably all the individual wires of the conductors 210, 220 are clamped. Subsequently, the end of the second conductor 220 can be inserted into the open half-shell on the other side of the connecting body 204 and in particular does not have to be pushed in the longitudinal direction. This is advantageous because an axial displacement of such cable ladder due to their large mass is possible only with the use of high forces.

The FIG. 5 shows a longitudinal section through a fourth embodiment of the invention with a device 301, wherein in each case a first part 304a of the connecting body is mounted on one end of a conductor 310, 320. Subsequently, the two first parts 304a are connected to a connecting element 340, which in turn can be connected to the two first parts 304a. The contact bodies 332 are introduced and compressed by screwing in the force introduction elements 318 and pressurized. The self-adjusting bias voltage at the force accumulators 328 can be read from outside the device 301 on the basis of the axial position of pin-shaped signal elements 354 which are arranged in the force accumulators 328 and extend radially outwards and pass through radial bores in the connecting element 340. For example, when the tapered portions of the force accumulators move axially toward the center of the device 301, the signal element 354 is entrained and at the axial position of the signal element 354 it can be read from outside the device 301 how much the force accumulator 328 is biased.

In a modified embodiment, the radial bore in the connecting element 340 for the passage of the signal element 354 may be only slightly larger than the dimension of the signal element 354, so that no axial relative movement of the signal element 354 relative to the connecting element 340 is possible. Instead, it points in the force giver 328 existing receiving opening for the signal element 354 has an inclined surface, so that during an axial relative movement of the energy accumulator 328 relative to the connecting element 340, the signal element 354 slides along the inclined surface and is thereby displaced radially in the radial bore, so that the bias of the energy accumulator 328 from outside the device 301 can be read on the basis of the radial position of the signal element 354. For example, the signal element 354 is only visible or is flush with the connecting element 340 when the energy storage 328 is sufficiently biased and thus the contact force is sufficient. The signal element 354 may be axially and / or radially displaceable with spring force loading in order, for example, to eliminate the influence of the weight.

The FIG. 6 shows a longitudinal section through a likewise three-part fifth embodiment of the invention with a device 401, in which the two first parts 404a of the connecting body are also mounted in each case on one end of a conductor 410, 420, then these two first parts 404a but with a multi-part connecting element 440th be connected, for example, by two half-shells screwed together. A holding body of the energy accumulator 428 comprising the spring elements can project axially into the two first parts 404a of the connecting body, in particular at its end, each having an external thread and thus can be screwed into the first two parts 404a, and through an end-side inner cone section form an axial stop for the ends of the two conductors 410, 420.

An advantage of the described three-part embodiments is that both conductor ends can be pre-assembled individually and independently of each other. The sliding of the two ends 301, 410, 320, 420 of the device 301, 401 assigned to the conductors is thus very easily possible, In particular, the associated cables do not have to be moved. When screwing the central connecting element 340, 440, the conductors 310, 410, 320, 420 are centered and the end faces firmly clamped.

The two such pre-assembled ends are brought into a coaxial position and electrically and mechanically connected to the half-shells. The half-shells can also consist of more than two segments. The positive connection for the mechanical and electrical connection can be made by a thread or circumferential grooves. The positive connection of the individual parts of the compound improves the mechanical strength. The minimization of remaining cavities increases the mass fraction and improves the low-loss power transmission

The FIG. 7 shows a longitudinal section through a sixth embodiment of the invention with a device 501, which can be used for a plug-in system with lamellar contacts. In such a plug-in connector part, no high demands are placed on the axial tensile load capacity of the conductor connection as a rule. The conductor end face is prepared and the connection body 504 is slid. The connecting body 504 has on the outside a circumferential groove into which a contact blade 556 is inserted.

The connecting body 504 is filled with the contact medium 530 and pushed onto the end of the conductor 510 and mechanically fixed with the retaining screws 542 on the conductor end. A conical surface 558 on the connecting body 504 takes over the centering and the sealing of the edge of the end face of the conductor 510. Subsequently, the contact force is biased by the force accumulator 528, which can be screwed into the connecting body 504 on the opposite end of the conductor 510.

The FIG. 8 shows a longitudinal section through a seventh embodiment of the invention with a device 601, which can be used for example for Schraubanschlussbolzen cable terminations and can be constructed according to the same construction principle as the devices described above. Depending on the application, the end section for receiving the connection fitting of an overhead line or the screw connection to a busbar system can be, for example, a solid round bolt, a flat, rectangular connection lug with bores or, as in FIG FIG. 8 shown in dashed lines - be designed as a cable lug 660. For example, a screwed design with retaining screws 642 is illustrated for the kiteriterseitigen end, pressed or other versions of the connection types are also possible.

The energy accumulator 628 can be screwed into a bore in the connecting body 604, which forms an acute angle of preferably more than 15 ° and less than 80 ° with the longitudinal axis of the device 601, in particular more than 20 ° and less than 65 ° and preferably more than 30 ° and less than 45 °.

Claims (12)

1. An apparatus (1) for making contact with an electrical conductor (10, 20), in particular a cable conductor of a power supply cable, wherein the apparatus (1) has a connecting body (4) which delimits a receiving space (6) into which the conductor (10, 20) with which contact is to be made can be inserted with its front end, and wherein the apparatus (1) has a contact medium (30) with which electrical contact can be made with the front end of the conductor (10, 20) accompanied by the action of a contact force, wherein the contact medium (30) has a plurality of electrically conductive contact bodies (32) which are introduced into the receiving space (6) and bear against one another and of which at least a part can be brought into electrical contact-making contact with the front end of the conductor (10, 20), characterised in that the contact bodies (32) have an at least partially spherical surface, preferably are designed ball-shaped, and that the apparatus (1) has at least one force-application element (18) acting on the contact medium (30) with which the contact force can be applied to the contact medium (30).
2. The apparatus (1) according to claim 1, characterised in that the contact force of one contact body (32) can be transmitted to adjacent bearing contact bodies (32) and/or the conductor (10, 20) with which contact is to be made and/or the connecting body (4).
3. The apparatus (1) according to one of the preceding claims, characterised in that the contact bodies (32) are shaped such that the contact force can be transmitted in a substantially direction-independent manner to adjacent bearing contact bodies (32) and/or the conductor (10, 20) with which contact is to be made and/or the connecting body (4).
4. The apparatus (1) according to one of the preceding claims, characterised in that the contact bodies (32) have an electrically conductive surface coating which constantly has a lower contact resistance compared with the material of the contact bodies.
5. The apparatus (1) according to one of the preceding claims, characterised in that the contact medium (30) has a pasty mass (34), in which the contact bodies (32) are embedded.
6. The apparatus (1) according to one of the preceding claims, characterised in that the apparatus (1) has a force storage means (28) acting on the contact medium (30), with which the contact force can be constantly maintained.
7. The apparatus (1) according to one of the preceding claims, characterised in that the apparatus (1) has at least one force indicator (36) or at least one signal element (354), each of which indicates that the contact medium (30) is adequately tensioned by means of the force storage means or contact storage means (28).
8. The apparatus (1) according to one of the preceding claims, characterised in that the apparatus (1) has a fixation device for fixing the conductor (10, 20) with which contact is to be made to the connecting body (4), in particular for fixing the axial position of the conductor (10, 20) with which contact is to be made relative to the connecting body (4).
9. A connection or connecting device with an apparatus (1) according to one of the preceding claims and with a contacted electrical conductor (10, 20), in particular with a multi-wire cable conductor of a power supply cable, wherein at least a part of the contact bodies (32) is in electrical contact-making contact with the front end of the conductor (10, 20).
10. The connection or connecting device according to claim 9, characterised in that at least a part of the contact bodies (32) has an at least partially curved surface, in particular an at least partially spherical surface, and preferably in that at least a part of the contact bodies (32) is formed ball-shaped, and in that the radius of the curved surface is less than 50% of a narrow side of the front surface of the contacted conductor (10, 20) or of the wires of a multi-wire conductor (10, 20), in particular less than 40% and preferably less than 25%.
11. The connection or connecting device according to claim 9 or 10, characterised in that the conductor (10, 20) has multiple wires, and that at least one expansion element (150) is inserted into the front end of the contacted conductor (10, 20), preferably that an expansion element (150) is inserted centrally into the front end of the contacted conductor (10, 20).
12. The connection or connecting device according to one of claims 9 to 11, characterised in that an annular element (148) is mounted on or near to the front end on the contacted conductor (10, 20), the external diameter of which is adapted to the receiving space (6) of the connecting body (4), in particular that the external diameter of the annular element (148) corresponds substantially to the clear width of the receiving space (6) of the connecting body (4), and/or the internal diameter of which is adapted to the external diameter of the conductor (10, 20) with which contact is to be made, in particular that the internal diameter of the annular element (148) corresponds substantially to the external diameter of the conductor (10, 20) with which contact is to be made.

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