APPARATUS FOR MAKING CONTACT WITH AN ELECTRICAL CONDUCTOR, AND CONNECTION OR CONNECTING DEVICE WITH AN APPARATUS OF THIS KIND

Abstract

The invention relates to 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 by way of its end, and wherein the apparatus (1) has a contact medium (30) with which electrical contact can be made with the end of the conductor (10, 20) under the action of a contact force, characterized in that the contact medium (30) has a large umber of electrically conductive contact bodies (32) which are introduced into the receiving space (6) and bear against one another and of which at least some can be brought into electrical contact-making contact with the end of the conductor (10, 20).

Claims

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 by means of 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) under the action of a contact force, characterized in that 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 some can be brought into electrical contact-making contact with the front end of the conductor (10, 20).

2. The apparatus (1) according to claim 1, characterized 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 claim 1, characterized in that the contact bodies (32) are shaped such that the contact force can be transmitted in an essentially 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 claim 1, characterized in that at least part of the contact bodies (32) has an at least partially curved surface, in particular an at least partially spherical surface, and preferably at least part of the contact bodies (32) is formed ball-shaped.

5. The apparatus (1) according to claim 1, characterized 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.

6. The apparatus (1) according to claim 1, characterized in that the contact medium (30) has a pasty mass (34), in which the contact bodies (32) are embedded.

7. The apparatus (1) according to claim 1, characterized in that the apparatus (1) has at least one force application element (18) acting on the contact medium (30), by means of which the contact force can be introduced into the contact medium (30).

8. The apparatus (1) according to claim 1, characterized in that the apparatus (1) has a force storage means (28) acting on the contact medium (30), by means of which the contact force can be constantly maintained.

9. The apparatus (1) according to claim 1, characterized in that the apparatus (1) has at least one force indicator (36) or at least one signal element (354), which indicates that the contact medium (30) is adequately tensioned by means of the force storage means or contact storage means (28).

10. The apparatus (1) according to claim 1, characterized 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).

11. A connection or connecting device with an apparatus (1) according to claim 1 and with a contacted electrical conductor (10, 20), in particular with a multi-wire cable conductor of a power supply cable, wherein at least some of the contact bodies (32) are in electrical contact-making contact with the front end of the conductor (10, 20).

12. The connection or connecting device according to claim 11, characterized in that at least part of the contact bodies (32) has an at least partially curved surface, in particular an at least partially spherical surface, and preferably at least 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%.

13. The connection or connecting device according to claim 11, characterized 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).

14. The connection or connecting device according to claim 11, characterized 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) essentially corresponds 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) essentially corresponds to the external diameter of the conductor (10, 20) with which contact is to be made.

Description

[0034] FIG. 1 shows a longitudinal section through a first exemplary embodiment of the invention,

[0035] FIG. 2 shows a longitudinal section of the first exemplary embodiment rotated 90 about the longitudinal axis,

[0036] FIG. 3 shows a longitudinal section through a second exemplary embodiment,

[0037] FIG. 4 shows a longitudinal section through a third exemplary embodiment,

[0038] FIG. 5 shows a longitudinal section through a fourth exemplary embodiment,

[0039] FIG. 6 shows a longitudinal section through a fifth exemplary embodiment,

[0040] FIG. 7 shows a longitudinal section through a sixth exemplary embodiment, and

[0041] FIG. 8 shows a longitudinal section through a seventh exemplary embodiment.

[0042] FIG. 1 shows a longitudinal section through a first exemplary embodiment of the invention with an apparatus 1 according to the invention for making contact with a multi-wire electrical conductor 10, in this case for connecting the first multi-wire electrical conductor 10 to a second multi-wire electrical conductor 20, which is the cable conductor 10, 20 of a first power supply cable 12 or of a second power supply cable 22. The two conductors 10, 20 lie in the region of the apparatus 1 coaxial to the longitudinal axis 2 of the apparatus 1. FIG. 2 also shows a longitudinal section through the apparatus 1, in which the apparatus 1 is, however, rotated 90 about the longitudinal axis 2.

[0043] The first exemplary embodiment serves to connect conductors 10, 20 having the same cross section and uses as an external contact system the tubular connecting body 4 which, like a normal press connector, is slid onto the prepared ends of the conductors 10, 20 at the left and right and is pressed in, for example, with hydraulic tools. In a similar way to the case of a conventional press connector, with appropriate conductivity the connecting body 4 can also be used for the power transmission of the bare conductor wires of the two conductors 10, 20, which conductor wires are contacted on the surface. Because, however, possible insulating layers were not removed from the individual wires and only the two outer layers are, from experience, involved in the transport of current in the case of multilayer cables, this alone does not establish an adequate electrical contact. The pressing thus ensures in particular that the two ends of the conductors 10, 20 are fixed on the connecting body 4 and are thus connected to one another in a mechanically stable manner.

[0044] Because the front ends 14, 24 of the conductors 10, 20 are thus also radially clamped and can only move slightly or not at all in the longitudinal direction, a receiving space 6 is delimited axially by the two conductors 10, 20 and radially by the connecting body 4, into which receiving space contact bodies 32 are introduced, which are embedded in a pasty mass 34 and together with it form the contact medium 30 of the apparatus 1, which is only partially depicted for reasons of clarity.

[0045] The contact bodies 32 are formed by balls made from copper, which have a uniform size and are covered with a 3 m to 5 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 can comprise a silicone gel or another paste with suitable viscosity.

[0046] After the introduction of an adequate quantity of the contact medium 30, for example via the two first threaded openings 16 abutting the receiving space 6 and arranged one behind the other along the longitudinal axis 2, a threaded pin or a tear-off screw acting as a force application element 18 is screwed into these threaded openings 16 and the receiving space 6 is thus closed and the contact medium 30 is placed under pressure with further screwing in.

[0047] The apparatus also has two force storage means 28, which each have a set of disk springs 38 and are inserted into the connecting body 4 radially at sides which are axially opposite one another, and in particular are screwed into corresponding second threaded holes 26 and then stuck therein. The two force application elements 18 are screwed into the connecting body 4 and tightened until force indicators in the form of signal elements 36 on the force storage means 28 indicate that the contact medium 30 is adequately tensioned. The force storage means 28 are dimensioned such that they maintain the minimum necessary holding force even if, due to thermal load changes and constant relaxation losses, the volume between the two conductors 10, 20 were to expand or the ends of the two conductors 10, 20 were to nevertheless move a little.

[0048] FIG. 3 shows a longitudinal section through a second exemplary embodiment of the invention with an apparatus 101, in which a one-part tube is pushed as a connecting body 104 over the ends of the two different or cross-sectionally identical conductors 110, 120. The two conductors 110, 120 are then fixed by means of the axially outermost holding screws 142 to the connecting body 104, which form part of a fixing device of the apparatus 301; the central part 144 with the force storage means 128 or spring sets 138 is already installed in the connecting body 104 and fixed there axially and radially at the center. With such a design, a portion of the current load can flow over the holding screws 142 and the connecting body 104, however this is not absolutely necessary and thus permits more compact designs of the apparatus 101. An advantage of this exemplary embodiment is that all connections can be tightened with customary tools for attachment devices and no special tools are required.

[0049] The preferably ball-shaped contact bodies 132 are introduced via the still open holes 116 for the force application elements 118, until the receiving space 106 between the conductors 110, 120 is completely filled. The contact force is applied by means of the force application elements 118, which are formed, for example, by threaded pins and which are finally screwed into the holes 116 and tightened, until no screw protrusion can be seen.

[0050] The centering screw 146 in the center of the connecting body 104 fixes the pre-tensioned force storage means 128 with their sets of disk springs 138. By means of torque-controlled tightening of the total of four force application elements 118 of the dimension M12, the contact bodies 132 are placed under pressure and the force storage means 128 are pre-tensioned.

[0051] The connecting body 104 can be formed by a tube or also by connectable half shells, which can be placed around the conductors 110, 120 and clamped by means of a suitable device relative to one another and to the conductors 110, 120.

[0052] An annular element 148 is mounted on the two conductors 110, 120 at their front end, the external diameter of which is adapted to the receiving space 106 of the connecting body 104, and in particular essentially corresponds to the clear width of the receiving space 106 of the connecting body 104, and the internal diameter of which is adapted to the external diameter of the conductor 110, 120 with which contact is to be made, in particular essentially corresponds to the external diameter of the conductor 110, 120 with which contact is to be made. The conductors 110, 120 are thus centered in the connecting body 104 and their circumferential contour is ensured and is preferably circular. The annular elements 148 extend over the front end of the conductor 110, 120 while forming an annular bar 152 directed radially inwards, which forms a stop when the annular element 148 is slid onto the conductor 110, 120.

[0053] An expansion element 150 is inserted centrally into the front end of the two conductors 110, 120, which expansion element has several sections, at least a portion of which are frusto-conical and which can be detached from one another in a preferably tool-free manner. The contour of the depicted longitudinal section through the expansion element 150 is also conical, so that the associated conductor 110, 120 is expanded all the more and is thus pressed into contact with the inside of the annular element 148 the further the expansion element 150 is introduced into the conductor 110, 120.

[0054] FIG. 4 shows a longitudinal section through a third exemplary embodiment of the invention with an apparatus 201, the installation of which is simplified in that a second part 204b, in particular a second half, of the two-part or multiple-part tubular connecting body 204 can be taken off a first part 204a and mounted on the first part 204a again and fixed there, for example, with a ring, once the connecting body 204 is in the right position relative to the conductors 210, 220. It is also possible for both sides of the connecting body 204 to be formed in such a way.

[0055] For the installation, one side of the connecting body 204 is pushed onto the end of the first conductor 210 and fixed there by means of the holding screws 242. In the axial direction, two or more rows of holding screws 242 which are preferably equidistantly spaced apart in the circumferential direction can be provided, wherein the holding screws 242 of adjacent rows can be offset relative to one another in the circumferential direction, so that several and preferably all individual wires of the conductors 210, 220 are clamped. The end of the second conductor 220 can then be inserted into the open half shell on the other side of the connecting body 204 and, in particular, must not be pushed in in the longitudinal direction. This is advantageous because an axial movement of such cable conductors is only possible by application of significant forces due to their large dimensions.

[0056] FIG. 5 shows a longitudinal section through a fourth exemplary embodiment of the invention with an apparatus 301, in which a first part 304a of the connecting body is mounted on an end of a conductor 310, 320. The two first parts 304a are then connected with a connecting element 340, which is in turn connectable with the two first parts 304a. The contact bodies 332 are introduced and compressed and placed under pressure by means of screwing in of the force application elements 318. The ensuing pre-tensioning on the force storage means 328 can be measured from outside the apparatus 301 by means of the axial position of pin-shaped signal elements 354, which are arranged in the force storage means 328 and extend radially outwards and penetrate radial holes in the connecting element 340. When the conical sections of the force storage means move, for example, axially to the center of the apparatus 301, the signal element 354 is carried along and, at the axial position of the signal element 354, it is possible to measure from outside the apparatus 301 to what extent the force storage means 328 are pre-tensioned.

[0057] In one modified embodiment, the radial hole in the connecting element 340 for the passage of the signal element 354 can be only insignificantly 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, the receiving opening for the signal element 354 provided in the force storage means 328 has an angular face so that, in the case of an axial relative movement of the force storage means 328 relative to the connecting element 340, the signal element 354 slides along the angular face and is thus moved radially in the radial hole, so that the pre-tensioning of the force storage means 328 can be measured from outside the apparatus 301 by means 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 force storage means 328 is adequately pre-tensioned and the contact force is thus adequate. The signal element 354 can be able to be moved axially and/or radially under a spring force load in order to eliminate the influence of the weight force, for example.

[0058] FIG. 6 shows a longitudinal section through a similarly three-part fifth exemplary embodiment of the invention with an apparatus 401, in which the two first parts 404a of the connecting body are also each mounted on an end of a conductor 410, 420, however, these two first parts 404a are then connected with a multi-part connecting element 440, for example by means of two half shells which can be screwed to one another. A holding body of the force storage means 428 surrounding the spring elements can project into the two first parts 404a of the connecting body axially by means of its two axial end sections opposite one another, in particular, it can have an external thread at the end and thus be able to be screwed into the two first parts 404a, and can form an axial stop for the ends of the two conductors 410, 420 by means of an end inside taper section.

[0059] One advantage of the described three-part exemplary embodiments is that both conductor ends can be mounted in advance individually and independently of one another. The pushing on of the two ends of the apparatus 301,401 assigned to the conductors 310, 410, 320, 420 is thus very easily achievable, in particular the associated cables do not have to be moved for this purpose. When the central connecting element 340, 440 is screwed on, the conductors 310, 410, 320, 420 are centered and the front sides are firmly clamped.

[0060] The two ends thus mounted in advance are moved into a coaxial position and electrically and mechanically connected with the half shells. The half shells can also consist of more than two segments. The form fitting for the mechanical and electrical connection can take place by means of a thread or circumferential grooves. The form-fitting connection of the individual parts of the connection improves the mechanical strength. The minimizing of remaining cavities increases the mass percentage and improves the low-loss power transmission.

[0061] FIG. 7 shows a longitudinal section through a sixth exemplary embodiment of the invention with an apparatus 501, which can be used for a plug-in system with lamellar contacts. In the case of such a pluggable connection part, there are generally no significant demands made with respect to the axial tensile loading capacity of the conductor connection. The conductor front surface is prepared and the connecting or connection body 504 is pushed on. The connecting body 504 has a circumferential groove on the outside, into which a contact lamella 556 is inserted.

[0062] The connecting body 504 is filled with the contact medium 530 and pushed onto the end of the conductor 510 and mechanically fixed on the conductor end by means of the holding screws 542. A conical surface 558 on the connecting body 504 realizes the centering and the sealing of the edge of the front surface of the conductor 510. The contact force is then pre-tensioned by means of the force storage means 528, which can be screwed into the connecting body 504 on the front side opposite the conductor 510.

[0063] FIG. 8 shows a longitudinal section through a seventh exemplary embodiment of the invention with an apparatus 601, which can be used, for example, for screw connection bolts on cable terminations and can be constructed according to the same design principle as the previously described apparatuses. The end section for receiving the connection fitting of an open wire or the screw connection to a busbar system can be designed, depending on the application, for example as massive round bolts, as a flat rectangular connecting lug with holes, oras depicted with dashed lines in FIG. 8as a cable shoe 660. At the cable conductor end, a screwed embodiment with holding screws 642 is depicted by way of an example, with compressed embodiments or other embodiments of the connection types also being possible.

[0064] The force storage means 628 can be screwed into a hole in the connecting body 604, which hole creates an acute angle with the longitudinal axis of the apparatus 601 of preferably more than 15 and less than 80, in particular more than 20 and less than 65, and preferably more than 30 and less than 45.