EP2850696B1 - Method and device for producing an operative connection between a connector and a cable - Google Patents

Description

The invention is in the field of coaxial cables and coaxial connectors for operatively connecting such coaxial cables, as well as processing coaxial cables and coaxial connectors into assemblies.

Coaxial cables for transmitting high frequency signals are known in the art. These cables have an inner conductor, which is surrounded by a dielectric, an outer conductor and a cable sheath. Such cables have dimensions adapted to their field of application and to the signal strength to be transmitted. From the prior art connectors for connecting such cables are known. Such connectors also have a coaxial construction and are matched to the cable dimensions. As a result, virtually every cable requires a connector tailored to its dimensions, resulting in a very large variety of variants.

Rotary kneading machines have been known from the prior art since the beginning of the last century, by means of which ductile materials can be formed continuously or discontinuously. As a rule, these rotary swaging machines have a forming tool consisting of two or four jaws arranged in pairs opposite one another. The jaws of the forming tool are deflected, for example, by rollers rotating in the outside in the radial direction inwards. At the same time they move in the circumferential direction. The forming tool has a central, usually continuous working opening, which has a tapered cross section in the longitudinal direction. Workpieces to be machined can be inserted into the working opening of the forming tool introduced and removed by the same or - in a continuous process - an opposite second opening again. Inside the work opening, the workpiece is continuously reshaped by the jaws moving in the radial and circumferential directions. The working opening has a variable cross-section due to the movement of the jaws. Rotary swaging is used, for example, in the manufacture of wire ropes or forgings in the automotive industry. From the patent literature, several fields of application for rotary kneading machines are known. Some selected examples are briefly described below.

The US patent issued on November 4, 2003 US6641444B2 Yazaki Corporation describes a structure and a method for assembling an electric cable and a cable end by means of rotary swaging. For this purpose, the insulation is replaced only at the cable end, so that the stranded conductor is exposed. This is then inserted into a hollow cylindrical sleeve. By means of rotary kneading, the sleeve is then compressed in the radial direction. Compression compresses the stranded conductor and thus lowers the electrical resistance.

The US Patent issued on 13.02.2007 US7174633B2 Yazaki Corporation also describes a method of connecting an electrical cable to a cable end. For this purpose, an electrically conductive adhesive (for example a paste of epoxy and nickel powder) is introduced into a tubular end of a cable end piece. Subsequently, the previously stripped stranded conductor of the cable end is inserted into the bore. By means of rotary swaging, the tubular cable end piece is then radially compressed and brought into close contact with the stranded conductor. The nickel powder in the paste is intended as a conductive filler destroy possible oxide layers on the metal parts and increase the conductivity.

The published on 06.10.2011 US patent application US2011244721A John Mezzalingua Associates, Inc. deals with a method for terminating a coaxial cable. First, a portion of the insulating layer is removed. Thereafter, the diameter of the inner conductor is partially reduced by means of a rotatable Koaxialkabelabschlusswerkzeugs while a part of the insulator removed (cored). Finally, an outer connection structure is attached to the inner connection structure. A tool for terminating a coaxial cable and a terminated coaxial cable are also disclosed. This application does not disclose a circular kneading in the sense mentioned above.

The International Patent Application published on 02.10.2003 WO03080269 from the Boeing Company is concerned with the termination of tension wires in aircraft, in which sleeves are converted on the ends by rotary swaging into balls for the load introduction.

The published on 10.10.1984 British patent application GB2137823 deals with a coaxial cable. Only in dependent claim 11 it is mentioned that the sleeve could be fixed by swaging.

The European Patent Application published on 27.03.2002 EP1191631 the Yazaki Corporation. deals with a method for connecting a terminal to a wire. The terminal has a connecting portion which is designed as an open sleeve and is pressed over its entire edge, for example by rotary swaging.

An object of the invention is to show a method for providing a coaxial cable. Another object of the invention is to provide a method for To show active connections of a coaxial cable according to the invention with a coaxial connector according to the invention. Other objects of the invention are to show a coaxial cable, a coaxial connector, and a cable assembly with improved transmission characteristics.

This object is achieved by the invention defined in the claims.

When connecting coaxial cables to a connector, it is essential that various conditions and criteria be met to ensure an optimal connection. On the one hand, the resistance should, whenever possible, e.g. 50 ohms or 75 ohms. On the other hand, diameter jumps, which lead to unwanted signal reflections, or burrs should be avoided. Furthermore, it should be avoided that the surface, or the surface coating of the cable inner conductor is damaged, as this too can lead to a deterioration of the transmission behavior.

Another aspect of the invention is that for cables with different diameters, if possible identical connectors can be used. The goal is to reduce the number of different connectors. This is achieved by providing different cable inner conductors with a standardized end, which allows to use the same or only slightly variable coaxial connectors for different cable diameters. For example, in that the coaxial connectors have the same inner life.

Today's coaxial cable have inner conductor of a single wire or strand inner conductor of several (stranded together) wires. Such inner strand conductors have the advantage that they are very flexible. On the other hand, they tend to make the individual wires more difficult to contact.

Another aspect of the invention is to simplify or reduce the size of the coaxial connectors.

These aspects of the invention can be achieved by machining the end of the coaxial cable to be connected by means of a method according to the invention. Depending on the embodiment, this comprises the following method steps. It should be noted that, depending on the field of application, individual process steps can be omitted or the sequence of individual process steps can be changed or certain process steps can be linked to one another. In a first step, if present, a cable sheath is removed at a defined first length so that an outer conductor is exposed. If necessary, the outer conductor is removed at a defined second length, so that a dielectric disposed between the inner cable conductor and the outer conductor is exposed. In a further step, the dielectric is removed on a defined third length, so that a centrally located, coaxial with the outer conductor arranged cable inner conductor is exposed. In certain cases, the first and / or the second and / or the third length may be identical. If necessary, the cable inner conductor is cut to a certain length. Subsequently, the cable inner conductor is transformed by means of a rotary swaging device according to the invention in one or more steps in such a way that it receives a predefined shape. The rotary swaging device has at least two jaws, which are arranged rotatably about an axis. At the same time, the jaws are arranged movable relative to the axis in the radial direction. A first drive is used to rotate the jaws around the axis. A second drive is used to hammer driving the jaws in the radial direction during which the jaws rotate about the axis. The jaws each have at least one active surface directed inwards towards the axis, which serves to work a workpiece inserted between the jaws. During machining of the workpiece, the shape of the at least one active surface is transferred to the workpiece. Depending on the embodiment, the cutting of the inner conductor can be done by the rotary swaging, or by a corresponding configuration of the effective surfaces of the jaws, be integrated into this. The drives of the jaws are usually designed so that their movements overlap. For example, the jaws are continuously rotated about the axis while doing an inwardly directed, hammering movement. As a result, the material of the workpiece is compacted. Another advantage is that the gentle treatment does not destroy a surface coating that may be present.

Depending on the field of application, the cable inner conductor has areas with different diameters after forming. These have advantageously smooth transitions to each other, with sharp edges or uncontrolled jumps in diameter are usually avoided. In certain applications, retaining means (e.g., barbs) may be formed by swaging. For example, circumferential groove-shaped depressions or beads can be formed, which serve to increase the holding forces between the cable inner conductor and a connector connected to this Wirkinneninnenleiter.

In one embodiment, prior to forming a sleeve is placed on the end of the cable inner conductor. The sleeve is then reshaped together with the cable inner conductor and thus at least partially receives a new geometry. The sleeve can serve as an adapter for connecting a coaxial connector. Alternatively, the sleeve can also serve as an inner conductor of a coaxial connector. If necessary, the sleeve can have barbs by means of which the sleeve can be anchored in a dielectric of a coaxial binder. The barbs can also be made by swaging with the same or another tool. If necessary, one or more barbs can be formed on the inner conductor, for example in the event that the inner conductor of the cable serves as an inner conductor of the connector.

Advantages of this procedure are a very precise forming with a small tolerance (typically ± 0.02 mm) with very good reproducibility and repeatability. Other advantages include an exact, round geometry, especially for small cable entries. This results in a much better adaptation at high frequencies due to the high reproducibility and process reliability. Steps inside connectors, such as those produced by crimping and soldering today, can be avoided. For example, it is possible aufzustecken a sleeve on a cable inner conductor and reshape by swaging on the one hand and on the other hand to connect with each other, so that both parts at the end in the transition region have the same diameter or passed into each other with a flowing outer surface. Another advantage is that the same parts can easily be used in different configurations. This can reduce the number of parts. Another advantage is that connectors according to the inventive method may have a shorter overall length, since, for example, the cable inner conductor can serve as an inner conductor of the connector. The inventive method can also be guaranteed that the cable inner conductors no longer need to be deburred and sharpened in separate steps. This reduces the risk of chips getting inside connectors and assemblies. The risk of burrs being created on cable inner conductors which damage bushings can also be reduced. The inventive forming of cable inner conductors results in the advantages that the same parts / assemblies can be used with different cables. As a result, the diameter and the length of the connector can be reduced, which has a positive effect on the material consumption (depending on the field of application, a reduction of the size Inner conductor and body about 40% possible). With angle connectors Mehrfachkontaktierungen can be avoided due to spacers.

Further advantages are that at the end of an inner conductor a thickening, e.g. a ball can be formed by swaging. This has the advantage that it can be omitted squeezed sockets on the opposite side. In addition, it is possible to see the end of the inner conductor if necessary with one or more circumferential grooves and / or thickening, or to attach other profiles, which have a positive effect on the holding force and the quality of the signal transmission.

By means of the rotary swaging according to the invention, parts can be operatively connected to one another by cold welding. As a result, difficult crimping and soldering processes can be avoided or replaced, in particular for small parts (diameters). Furthermore, the e.g. In case of square crimp connections occurring contact problems with inner conductors are avoided, and the PIM behavior (passive intermodulation) can be improved. Also eliminates the problem with embrittling Lotstellen (gold in the tin). If required, the cable inner conductors can also be formed over the entire cable length by rotary swaging. A further advantage is that sheet metal material coated on one side is used by the rotary swaging according to the invention instead of solid material, which has a positive effect on the production costs.

In a variant, the method according to the invention for producing an operative connection between a coaxial cable and a coaxial connector comprises the following method steps: (a) if present, removing a cable sheath by means of a first tool on a defined first length; (B) removing a cable outer conductor by means of a second tool on a defined second length; (c) removing a dielectric by means of a third tool on a third length, so that a End of the inner conductor is exposed; (d) providing a rotary swaging device having a plurality of jaws which are rotatable around an axis of rotation in the direction of contact and can be deflected in the radial direction, each having at least one active surface; (e) introducing the end of the inner conductor into the effective region of the active surfaces so that the shape of the active surfaces is transferred to the end of the inner conductor and the end has at least one section with a defined diameter; (f) providing a coaxial connector; (G) inserting the inner conductor into a cable opening of a housing of the coaxial connector until the section of the defined diameter has reached a defined position inside the connector. For the effective connection of the cable inner conductor with a coaxial connector according to the invention, the end of the cable inner conductor can be inserted into a connection opening of a connector inner conductor. Alternatively or in addition, the end of the cable inner conductor is inserted into a sleeve. The sleeve can be kneaded together with the cable inner conductor. In one embodiment, the cable inner conductor may be pushed through a central bore of an insulator of the connector until it forms the connector inner conductor. A device for processing a coaxial cable according to the invention can have a first tool for removing a cable sheath at a defined length. Furthermore, the device may have a second tool for removing an outer conductor to a defined length. Furthermore, the device may have a third tool for removing a dielectric at a defined length. The device has a rotary swaging device which has a plurality of jaws which are rotatable about an axis of rotation and can be deflected in the radial direction, each having at least one active surface for processing a cable end. The first and / or the second and / or the third tool may be one or more knives. The knives can be adjustable, or arranged to be movable relative to the coaxial cable. The device may include a holder for temporarily holding and positioning the coaxial cable. The device may comprise several rotary swaging devices with different active surfaces exhibit. At least one of the tools can be arranged in front of and / or next to the rotary swaging device. If necessary, the tools can be accommodated in different housings. A coaxial cable according to the invention generally has a cable inner conductor, a cable outer conductor arranged coaxially therewith and a dielectric arranged between them. One end of the cable inner conductor has at least one surface, which was produced by means of a rotary swaging device. At least one surface may have a coating applied prior to swaging. The end of the cable inner conductor may comprise a sleeve, which is operatively connected to the cable inner conductor by swaging. The sleeve and the cable inner conductor may have the same outer diameter after swaging in the joint area.

Fig. 1

ein erfindungsgemässes Verfahren in einer perspektivischen Darstellung;

Fig. 2

das erfindungsgemässe Verfahren in einer Seitenansicht;

Fig. 3

eine erste Ausführungsform eines erfindungsgemässen Verbinders;

Fig. 4

einen zweite Ausführungsform eines erfindungsgemässen Verbinders;

Fig. 5

eine dritte Ausführungsform eines erfindungsgemässen Verbinders;

Fig. 6

eine vierte Ausführungsform eines erfindungsgemässen Verbinders.

Further aspects of the invention will be explained in more detail with reference to the embodiment described in the following figures. Show it:

Fig. 1

an inventive method in a perspective view;

Fig. 2

the inventive method in a side view;

Fig. 3

a first embodiment of a connector according to the invention;

Fig. 4

a second embodiment of a connector according to the invention;

Fig. 5

a third embodiment of a connector according to the invention;

Fig. 6

A fourth embodiment of a connector according to the invention.

FIG. 1 shows schematically and greatly simplified a method according to the invention in a perspective view. FIG. 2 shows the same procedure in a side view.

A coaxial cable 1 has an inner conductor 2, an outer conductor 3 arranged coaxially therewith and a dielectric 4 arranged therebetween. The outer conductor 3 is surrounded by a cable sheath 5.

In a first step, the cable sheath 5 is removed by means of a first tool 6 on a defined first length L1. Subsequently, the outer conductor 3 is removed by means of a second tool 7 on a defined second length L2. In a further step, the dielectric 4 is removed by means of a third tool 8 at a third length L3, so that the inner conductor 2 is exposed. In one embodiment, the second and third lengths L2, L3 are formed to be approximately equal in length. The inner conductor 2, which in the unprocessed state has an approximately cylindrical shape, is subsequently formed by means of a rotary swaging device 9 according to the invention in one or more operations. The rotary swaging 9 has in the embodiment shown on three jaws 10 (depending on the application, other jaw numbers, eg. 2 or 4 are possible), which are arranged rotatably driven about an axis 11 and driven in the radial direction. The rotational movement about the axis 11 and the hammering deflection movement in the radial direction are schematically represented by first and second arrows 12, 13. The jaws 10 are shown in an extended state, so that the inner life is visible. In the production position, the jaws 10 are moved together in the radial direction (second arrows 13), so that shaping active surfaces 14 can act on the inner conductor 2 and plastically reshape it. This ensures that the shape of the active surfaces 14 is transmitted to the end 15 of the inner conductor 2. If necessary, the forming process in several steps through several rotary swaging 9 done. The preparation of the coaxial cable, ie the removal of the outer layers and the exposure of the inner conductor 2 can be carried out in a specially designed rotary swaging 9. If necessary, one or more steps may be performed by one or more other tools (not shown). At least during the rotary swaging process, the coaxial cable 1 is precisely positioned and held by means of a holder (not shown in detail). In one embodiment, the tools 6-8 are configured as cutting tools and are moved towards the outer layers 3-5 of the coaxial cable 1 in the radial direction until the corresponding layer is separated. Subsequently, the layer can be pulled off in the direction of the cable end 15.

The Figures 3-7 show four embodiments of inventive connectors 16. The connector 16 each have a housing 17 in which a connector inner conductor 18 is arranged, which is held by an insulator 19 with respect to the housing 17. The housing 17 serves as a rule at the same time as an outer conductor of the connector 16 for signal transmission. The connectors 16 typically additionally include a locking means 20 by means of which the connector 16 may be attached to, for example, a socket or other connector (both not shown). In the in the Figures 3-7 shown connectors 16, the housing 17, the insulator 19, and the operative connection means 20 are shown in section, so that the inner life of the connector is visible.

FIG. 3 shows an assembly 34 consisting of a connector 16 and a cooperatively connected coaxial cable 1. The connector 16 shown is an angled connector. The coaxial cable 1, which has been prepared by means of the method according to the invention, is seated in a cable opening 21 arranged perpendicular to the connector inner conductor 18. One end 15 of the inner conductor 2 is machined by rotary swaging and has a first portion 22 with a first diameter D1 and a second portion 23 with a second diameter D2. Subsequent to the second section, a spherical end cap 24 is formed here. An advantage of the method according to the invention is that, even with small diameters of the inner conductor 2, abrupt jumps in diameter, which under certain circumstances have a negative effect on the signal transmission, can be avoided.

The second diameter D 2 of the second section 23 is adapted to the diameter of a connection opening 26 of the connector inner conductor 18. The inner cable conductor 18 is made of sheet metal in the embodiment shown and has a pin-shaped configuration in the front region. In the rear area, where the connection opening 24 is located, it has a U-shaped cross-section with a clamping tongue 27, which is deflected upon insertion of the inner conductor 2 in the connection opening 24 in the view shown upwards (z-axis). The connection opening 24, or the clamping tongue 25 projecting into the latter, are matched to the second diameter D2 of the second section 23, so that the inner conductor 2 is securely connected to the latter after insertion into the inner connector conductor 18. Other types of fastening are possible. The connector inner conductor 18 can be brought by rotary swaging in the hollow cylindrical shape shown with the different diameters.

In the in FIG. 4 shown arrangement, the coaxial cable 1 is shown in addition to the connector 17, so that the inner life is better visible. The coaxial cable 1 is shown without a cable sheath. The connector 16 is a straight connector in which the cable inner conductor 2 and the inner connector conductor 18 are arranged on the same axis. The coaxial cable 1 is inserted into the cable opening 21 formed at the rear end of the housing 17 and the exposed outer conductor 3 is operatively connected to the housing 18. The end 15 of the inner conductor 2 is inserted into a sleeve 28, which simultaneously forms the connector inner conductor 18. The sleeve 28 is placed in advance on the inner conductor 2 of the coaxial cable 1 and then operatively connected together with this by rotary swaging. One advantage is that the inner conductor 2 and the sleeve 28, or respectively the inner connector conductor 18, can have the same diameter throughout (see second section 23). The use of a sleeve 28 is particularly appropriate when it is the inner cable conductor 2 is a Litzeninnenleiter, which consists of several individual wires. The connector inner conductor 18 has externally molded barbs 29, which serve for anchoring the connector inner conductor 18 in the insulator 19 of the connector 16. In the embodiment shown, the insulator 19 is pressed from the front to a first shoulder 30 in the housing 17. Subsequently, the connector inner conductor 18 is pressed together with the cable inner conductor 2 from the rear into a central bore 31 of the insulator 19, wherein the barbs 29 cling in the material of the insulator 19. Due to the inventive design, the connector 16 has the advantage that it has a comparatively short length.

At the in FIG. 5 The arrangement shown has a similar structure as the variant shown in Figure 4 . The inner conductor 2 is a so-called. Litzeninnenleiter, which consists of several stranded individual wires (not shown). The end 15 of the inner conductor 2 is kneaded round, so that the individual wires are operatively connected to each other by cold welding. If necessary, the individual wires can be subjected to a surface treatment, eg in a dipping bath. The connector inner conductor 18 is disposed of the central bore 31 of the insulator 19 and is held by this with respect to the housing 17 of the connector 16. The connector inner conductor 18 has a sleeve-shaped configured rear end with individual by slots 32 separated, distributed on the circumference of the sleeve 28 radially inwardly directed Has spring tongues 33. To connect to the connector inner conductor 18 of the cable inner conductor 2 is inserted into the sleeve-shaped portion 28 of the connector inner conductor 18. The spring tongues 33 are bent elastically outwards, so that they have a clamping effect on the cable inner conductor 2.

In the known from the prior art connector for connecting a Litzeninnenleiters an intermediate part is required. This has the disadvantage that higher costs incurred and the connector has a greater length. Other disadvantages are the Mehrfachkontaktierung required thereby, which can lead to a negative impact on the signal quality. <B> reference numerals </ b> L1 first length 21 Cable opening (housing) L2 second length 22 first section L3 third length 23 second part D1 first diameter 24 endcap D2 second diameter 25 Transition surface 1 coaxial 26 port opening 2 Inner conductor (cable inner conductor) 27 clamping tongue 3 outer conductor 28 Sleeve (for cable inner conductor) 4 dielectric 29 barb 5 cable sheath 30 first shoulder 6 first tool 31 centric bore (insulator) 7 second tool 32 Slots (sleeve connector inner conductor) 8th third tool 9 Rundknetvorrichtung 33 Spring tongues (sleeve connector inner conductor) 10 to bake 11 axis of rotation 34 Assembly (assembly consisting 12 first arrows (rotary motion) from cable and connector) 13 second arrows (radial movement) 14 Active surfaces (baking) 15 E nde (inner conductor) 16 Interconnects 17 casing 18 Connector inner conductor 19 insulator 20 Operative connection means

Claims (15)

1. A method for producing an operative connection between a coaxial cable (1) and a coaxial connector (16), comprising the following method steps:

   a. removing a cable sheath (5), if provided, over a defined first length (L1) by means of a first tool (6);

   b. removing an external conductor (3) over a defined second length (L2) by means of a second tool (7);

   c. removing a dielectric (4) over a third length (L3) by means of a third tool (8), so that an end (15) of the internal conductor (2) is exposed;

   d. providing a rotary swaging device (9) comprising a plurality of jaws (10) which are rotatable in the circumferential direction about an axis of rotation (11), can be deflected in a hammering manner in the radial direction and each comprise at least one active surface (14);

   e. introducing the end (15) of the internal conductor (2) into the active region of the active surfaces (14), so that the shape of the active surfaces (14) is transmitted to the end of the internal conductor (15) and the end (15) has at least one portion (23) having a defined diameter D2;

   f. providing a coaxial connector (16);

   g. pushing the internal conductor (2) into a cable opening (22) in a housing (17) of the coaxial connector (16) until the portion (23) having the defined diameter (D2) has reached a defined position in the interior of the connector (16).
2. The method according to claim 1, characterized in that, for operative connection, the end (15) of the internal cable conductor (2) is pushed into a connection opening (26) in an internal connector conductor (18).
3. The method according claim 2, characterized in that the end (15) of the internal cable conductor (2) is pushed into a sleeve (28).
4. The method according to claim 3, characterized in that the sleeve (28) is rotary swaged together with the internal cable conductor (2).
5. The method according to one of the preceding claims, characterized in that the internal cable conductor (2) is pushed through a central hole (31) in an insulator (19) of the connector (16) until said internal cable conductor (2) forms the internal connector conductor (18).
6. The method according to one of the preceding claims, characterized in that the second and the third lengths (L2, L3) are designed to be approximately the same.
7. A device (9) for processing a coaxial cable, comprising

   a. a first tool (6) for removing a cable sheath (5) over a defined length (L1);

   b. a second tool (7) for removing an external conductor (3) over a defined length (L2);

   c. a third tool (8) for removing a dielectric (4) over a defined length (L3);

   d. a rotary swaging device (9) comprising a plurality of jaws (10), which are rotatable about an axis (11), can be deflected in the radial direction with respect thereto and each comprise at least one active surface (14) for processing an end (15) of an internal conductor (2), so that the shape of the active surfaces (14) is transmitted to the end of the internal conductor (15) of the cable end (15), and the cable end (15) has at least one portion (23) having a defined diameter D2.
8. The device (9) according to claim 7, characterized in that the first and/or the second and/or the third tool (6, 7, 8) is a blade.
9. The device (9) according to one of claims 7 or 8, characterized in that the device (9) has a plurality of rotary swaging devices (9) having different active surfaces (14).
10. The device (9) according to one of claims 7 to 9, characterized in that at least one of the tools (6, 7, 8) is arranged in front of or beside the rotary swaging device (9).
11. A coaxial cable (1) comprising an internal cable conductor (2), an external cable conductor (3) arranged coaxially therewith and a dielectric (4) arranged therebetween, characterized in that an end (15) of the internal cable conductor (2) has at least one surface (22, 23, 24) which has been produced by means of a rotary swaging device (9).
12. The coaxial cable (1) according to claim 11, characterized in that the at least one surface (22, 23, 24) has a coating.
13. The coaxial cable (1) according to one of claims 11 or 12, characterized in that the end (15) of the internal cable conductor (2) comprises a sleeve (28), which is operatively connected to the internal cable conductor (2) by means of rotary swaging.
14. The coaxial cable (1) according to claim 13, characterized in that the sleeve (28) and the internal cable conductor (2) have the same external diameter.
15. An assembly (1, 16) consisting of a coaxial connector (16) and a coaxial cable (1) according to one of claims 11 to 14.

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