EP2523275B1 - Shielded cable and device for producing such a cable - Google Patents

Description

The invention relates to a prefabricated shielded cable, which in particular comprises a connector for transmitting RF signals according to claim 1.

The cables in question are used for example in motor vehicles or aircraft and are usually needed in large quantities. For cost-effective provision of appropriate cables a simple structure and ease of assembly are of great importance. In addition, such cables must be electromagnetically well shielded so that no radiated electromagnetic waves, for example, in the on-board electronics of the vehicle in question can cause interference. Furthermore, such cables must be made so that they can be transmitted with these signals with very high frequency, as required for example for a high-quality video signal transmission.

From the DE 10 2007 047 436 A1 a cable is known which has a shielded construction. In this case, a crimp connection is designed such that it has a so-called center recess.

In the EP 1 965 465 is a shielded cable, shown according to the preamble of claim 1.

In the EP 0 328 234 A2 there is shown a shielded cable having a crimped connection between a sleeve and a screen to be suitable for high electromagnetic shielding.

The invention has for its object to provide a cable which is very well shielded, so that the radiated electromagnetic power is miniert, or a high EMC-tightness is ensured. Furthermore, the cable should still be manufacturable with comparatively low production costs. In addition, a crimping device is to be created, can be produced by such cables.

This object is achieved by the features of claim 1.

According to the invention, the cable for transmitting RF signals comprises a screen, at least one core and an electrically conductive sleeve. The sleeve in turn has a longitudinal axis and, viewed geometrically, can be subdivided by a longitudinal sectional plane into a first geometric sleeve half and a second geometric sleeve half. Furthermore, the sleeve has a first portion and a second portion, wherein the portions are arranged offset from one another in the direction of the longitudinal axis. The sleeve also encloses the screen and is connected to the screen by crimping. The crimping is designed in such a way that the sleeve has at least one crimp ridge within the first section in the first sleeve half and is configured crimp-free in the second sleeve half. At the same time, the sleeve within the second section in the first sleeve half is crimped-free and has at least one crimping ridge in the second half of the sleeve.

A sectionally crimped-free shape of a sleeve half is to be understood in particular as meaning that the sleeve half in the relevant axial section is designed to be concave on the inside, so that there is a uniform pressing of the screen substantially without geometric disturbances. Alone the presence of press marks on the outside of the sleeve therefore can not justify that the relevant area of the sleeve should be seen as crimp-free.

In the following, RF signals are to be understood as signals which have been generated with the aid of high-frequency technology, that is also, for example, UHF or VHF signals. In particular, this includes digital signals with a transmission rate greater than or equal to 10 Mbit / s.

Advantageously, the sleeve has a third section, which is offset from the first and second sections in the direction of the longitudinal axis. In this case, the sleeve has at least one crimping ridge within the third section in the first sleeve half and is configured crimp-free in the second half-sleeve.

From a purely geometrical point of view, the cable according to the invention can also be characterized in such a way that the sleeve has at least one crimping ridge within a first cross section in the first half of the sleeve and crimp-free in the second half of the sleeve and the sleeve is crimp-free within a second cross-section in the first half of the sleeve and in the second sleeve half has at least one Crimpgrat. The cross sections are oriented orthogonally to the longitudinal axis and offset from one another in the direction of the longitudinal axis. In the case of a third section, this too can be considered as a third section.

The axial extent of a section results from the length of the crimp burrs, so that a section is as long as its longest crimp ridge. Usually, all crimp burrs in a section are the same length. Advantageously, the sections immediately adjoin one another so that there is always a crimp ridge in one of the sleeve halves over the entire crimp area.

In a further embodiment of the invention, the sleeve in the second section has a smaller diameter than in the first section. If the sleeve also has a third section, the second section may have the smallest diameter compared to the first and third sections. The second section with the smallest diameter may be arranged in the direction of the longitudinal axis between the first and third sections.

Advantageously, the sleeve is executed at least within the sections, ie in the region of the crimp, closed over its circumference, that is without an opening or slot. Consequently, then the sleeve encloses the screen in the radial direction completely.

In an advantageous construction, the at least one crimp ridge in the first section has a greater axial extent than the at least one crimp ridge in the second section.

Advantageously, the crimp burrs are spaced apart from each other in a central angle about the longitudinal axis, which is smaller than 150 °, in particular smaller than 135 °. In the following, centering angle is to be understood as meaning, in particular, a midpoint angle about a point on the longitudinal axis within the respective section in which the respective crimp burrs are located.

Furthermore, the outer side of the crimp-free sleeve half in the second section can be made continuously convex. Alternatively or additionally, the outside of the crimp-free sleeve half in the first section can be made continuous convex. In particular, the crimp-free sleeve halves can be designed to be round outside over a central angle of at least 180 °.

In a further embodiment of the invention, the cable has four wires that are twisted together on. In particular, the cable can be constructed according to a SternVierer concept.

Advantageously, the cable in the first section and in the second section on an electrically conductive support bracket, wherein the screen rests both radially inwardly and radially outwardly of the support bracket. This two-sided concern can be achieved by folding the screen before crimping. The screen may consist of a plurality of individual wires as a braided screen, so that the individual wires abut both radially inwardly and radially outwardly on the support bracket or with the support bracket are pressed. The crimp-free sleeve halves are in particular designed such that they have an inner contour that run essentially parallel to the outer contour of the support bracket.

There is also described a crimping apparatus for making a cable having a screen, at least one wire radially inward of the screen and an electrically conductive sleeve having a longitudinal axis, the sleeve enclosing the screen and connected to the screen by crimping , The crimping device comprises two crimping dies. Each of the two crimping dies has a crimper as well as an anvil. The crimper and the anvil in each of the two crimping dies are offset with respect to the longitudinal axis. For crimping the sleeve, the two crimping dies are arranged relative to one another in such a way that they mesh with one another such that in each case a crimper interacts with an anvil when the crimping dies are moved relative to one another with respect to the longitudinal axis of the sleeve.

The crimping device can be designed such that at least one of the crimping dies has a saddle intended for a plastic deformation of the sleeve, the contour of which runs along a partial circle line. A partial circle line is to be understood as a line along a partial circle, that is to say along an open (not closed) circular line which extends over an angle of less than 360 °.

In the simplest case, a crimping stamp comprises exactly one crimper and one anvil. The crimping device may be constructed from two identical Crimpstempeln, wherein the first crimping can be arranged with respect to a point on the longitudinal axis of the sleeve point symmetrical to the other crimping die. The two identical Crimpstempeln can thus be used to each other rotated about its vertical axis in the crimping device. Furthermore, all crimpers of the crimping device and / or all anvils of the crimping device can be of identical construction.

Advantageously, the crimping device comprises two crimping dies, wherein one of the crimping dies has two crimpers and one anvil. Alternatively or additionally, one of the crimping dies can have a crimper and two anvils. In each case, the crimper and anvil of a crimping die are offset relative to one another with respect to the longitudinal axis and can engage in one another for the purpose of crimping or pressing the sleeve.

In a further embodiment of the crimping device, one of the crimping dies is designed such that an anvil is arranged between two crimping tools or a crimper between two anvils. Advantageously, the crimping device has a crimping die, in which an anvil is arranged between two crimping tools and a crimping punch, in which a crimper is arranged between two anvils. The order crimper - anvil along the longitudinal axis is designed such that in each case a crimper can interact with an anvil.

The crimping device can be configured such that at least one crimping die is designed such that the anvil and crimper represent different components or different crimping inserts, which in particular are releasably joined together. Advantageously, at least one of the anvils or crimpers can then have a saddle intended for a plastic deformation of the sleeve, the contour of which extends over the entire thickness of the component parallel to the longitudinal axis. The different components may have different thicknesses.

All components of the crimping device, which serve as anvils, can each be designed with the same contour of the saddle. Likewise, all components of the crimping device, which serve as a crimper, each be designed with the same contour of the saddle.

The invention makes it possible to increase the conductivity of the crimp connection or to reduce the contact resistance, which results in a better shielding effect. The cables according to the invention are therefore insensitive to external electromagnetic radiation and also emit virtually no such radiation. Furthermore, in the production the cable according to the invention, the crimp height can be set very fine, so that high quality cables can be produced with high reproducibility.

In addition, the crimp connection between the sleeve and the shield has an extremely high tensile strength.

Advantageous embodiments of the invention will remove the dependent claims.

Further details and advantages of the cable according to the invention will become apparent from the following description of an embodiment with reference to the accompanying figures.

Figur 1

eine Schnittansicht entlang einer Längsschnittebene durch eine Hülse für ein geschirmtes Kabel vor der Verarbeitung,

Figur 2a

ein erstes Crimpeinsatzpaar zur Herstellung des geschirmten Kabels in einer Draufsicht,

Figur 3a

ein zweites Crimpeinsatzpaar zur Herstellung des geschirmten Kabels in einer Draufsicht,

Figur 3b

eine Schnittansicht des zweiten Crimpeinsatzpaars,

Figur 4a

ein montierter Crimpstempel zur Herstellung des geschirmten Kabels in einer Draufsicht,

Figur 4b

eine perspektivische Ansicht des montierten Crimpstempels,

Figur 5

eine Seitenansicht des Endbereiches des Kabels,

Figur 6

eine vergrößerte Schnittansicht entlang einer Querschnittebene X-X durch das Kabel,

Figur 7

eine vergrößerte Detailansicht auf eine Hülsenhälfte des Kabels,

Figur 8

eine vergrößerte Detailansicht auf die andere Hülsenhälfte des Kabels.

It show the

FIG. 1

a sectional view along a longitudinal sectional plane through a sleeve for a shielded cable before processing,

FIG. 2a

a first crimping insert pair for producing the shielded cable in a plan view,

FIG. 3a

a second crimping insert pair for the production of the shielded cable in a plan view,

FIG. 3b

a sectional view of the second Crimpeinsatzpaars,

FIG. 4a

a mounted crimping die for the production of the shielded cable in a plan view,

FIG. 4b

a perspective view of the mounted crimping die,

FIG. 5

a side view of the end portion of the cable,

FIG. 6

an enlarged sectional view along a cross-sectional plane XX through the cable,

FIG. 7

an enlarged detail view of a sleeve half of the cable,

FIG. 8

an enlarged detail view of the other half sleeve of the cable.

In the FIG. 1 a one-piece electrically conductive sleeve 7 is shown, which was manufactured by means of a deep drawing process and comprises a coupling end 7.7, which is suitable for producing a plug connection with a further coupling part. The sleeve 7 is designed in particular in the region which is provided for the subsequent crimping, substantially hollow cylindrical. The sleeve 7 can be associated with a longitudinal axis L, which in the first approximation represents an axis of symmetry. Incidentally, the sleeve 7 is closed at least in its hollow cylindrical tubular portion, so has no running over the entire length of the sleeve 7 slot. On the sleeve 7 a fitting 8 made of plastic is arranged by encapsulation. By receiving mandrels not shown in the figures, a form-fitting positionally correct seat between the fitting 8 and the sleeve 7 is achieved.

In the FIGS. 2a and 2b a first crimping insert 10 is shown which consists of a crimp 11 and an anvil 12. The crimper 11 and the anvil 12 each have a saddle 11.1, 12. 1, which is intended for the plastic deformation of the sleeve 7. The saddle 11.1, 12. 1 in the illustrated embodiment each have a contour which extends in accordance with a partial circle line. The radius R of the contour or the partial circle line is dimensioned equal in the region of the saddle 11.1, 12.1 for the crimper 11 and the anvil 12. The crimper 11 also includes two cheeks 11.2, 11.3, which are arranged opposite one another and serve as an inlet surface for the sleeve to be crimped 7. Like from the FIG. 2a As can be seen, therefore, the crimp 11 as the sum of the length of the contour of the saddle 11.1 and the cheeks 11.2, 11.3 a longer concave contour than the anvil 12, in which as a concave contour substantially only the contour of the saddle is 12.1. In the illustrated embodiment, the crimper 11 and the anvil 12 of the first crimping pair 10 have a thickness D of 2 mm.

In the FIGS. 3a and 3b a second crimping insert pair 20 is shown. This also includes a crimper 21 and an anvil 22, respectively a saddle 21.1, 22. 1. The radius r of the contour is dimensioned equal in size in the region of the saddle 21.1, 22. 1 for the crimper 21 and the anvil 22. The crimping insert pair 20 differs from the crimping insert pair 10 FIG. 2 inter alia in that the radius r is slightly smaller than the corresponding radius R in the crimping pair 10 according to the FIG. 2a , In contrast to the Crimpeinsatzpaar 10 according to the FIG. 2b have the crimper 21 and the anvil 22 according to the FIG. 3b only a thickness d of 1 mm. The crimper 21, as the sum of the length of the contour of the saddle 21.1 and the cheeks 21.2, 21.3, has a longer concave contour than the anvil 22, in which only the contour of the saddle 22.1 exists as a concave contour.

Furthermore, in the presented embodiment, a third crimping insert pair 30 (FIG. FIG. 4b ), which also includes a crimp 31 and an anvil 32. The two Crimpeinsatzpaare 10, 30 are made identical in the illustrated embodiment. Accordingly, the geometry of the crimping insert 31 corresponds to that of the crimping insert 11 according to FIGS FIGS. 2a, 2b and the geometry of the crimping insert 32 of that of the crimping insert 12 after FIGS. 2a, 2b ,

The specific for the plastic deformation of the sleeve 7 saddle 11.1, 12.1, 21.1, 22.1 of the six crimping inserts 11, 12, 21, 22, 31, 32 have over the entire thickness D, d a contour which is parallel to the longitudinal axis L. Accordingly, the crimpers 11, 21, 31 and the anvils 12, 22, 32 in the saddle 11.1, 12.1, 21.1, 22.1 in the direction of the longitudinal axis L no profile.

The three crimping pairs 10, 20, 30 will now be according to the FIGS. 4a and 4b into crimp punches 100, 200, so that the crimps 11, 21, 31 and the anvils 12, 22, 32 are offset relative to one another with respect to the longitudinal axis L. The first crimping die 100 comprises the crimps 11 and 31 as well as the anvil 22. In the case of the first crimping die 100, the anvil 22 is arranged between the two crimping 11, 31. The second crimping die 200 is associated with the anvils 12, 32 and the crimper 21. The crimper 21 is located at the crimping die 200 between the two anvils 12, 32nd

With the help of in the FIGS. 4a and 4b shown crimper 100, 200 is a cable according to the FIGS. 5 to 8 getting produced. The cable has centrally a filler 1 of insulating material around which four cores 2, which are each surrounded by an insulation 3, are arranged rotated. Radially outside with respect to the wires 2 with the insulation 3 is a screen 4, here in the form of a shield braid. The screen 4 is enclosed by the predominant cable length of an insulating jacket 6 ( FIG. 5 ). Such cables are often referred to as a star quad. The four wires 2 with their insulation 3 are twisted together, whereby a high crosstalk attenuation can be achieved.

In the course of assembling the cable, the insulating jacket 6 is first removed in an end region of an electrical line so that the shield 4 is exposed in this end region. Next, an electrically conductive support clip 5, which has a slot 5.1 (FIG. FIG. 6 Pressed and the screen 4 is folded around the support bracket 5 around or everted. On the folded screen 4 is then the sleeve 7 according to the FIG. 1 pushed. Such a sleeve 7 may also be referred to as outer conductor sleeve. The outer diameter of the sleeve 7 is in the region where a crimping to be performed slightly larger than twice the radius R, r of the saddle 11.1, 12.1, 21.1, 22.1.

By a crimping process, an electrical and mechanical bond between the sleeve 7 and the screen 4 is subsequently produced. For this purpose, the sleeve 7 located on the cable is placed between the crimping dies 100, 200. The Indian FIG. 4b illustrated crimping punch 100 is now moved toward the second crimping die 200 until the hollow cylindrical portion of the sleeve 7 is pressed against the screen 4 to the desired extent.

In the region of the sleeve 7, the cable thus produced has three circumferential sections I, II, III, which are axially offset relative to the direction of the longitudinal axis L of the sleeve 7. The axial extent of each of the sections I, II, III results from the thickness D, d of the crimpers 11, 21, 31 and the anvils 12, 22, 32 (see FIGS. 7 and 8 ). In the exemplary embodiment presented, therefore, the sections I and III have an axial extent of 2 mm, while the middle section II has an axial extent of 1 mm. The sections I, II, III can thus be interpreted geometrically as virtual slices with the thicknesses D and d and end faces, which are oriented orthogonal to the longitudinal axis L.

The sleeve 7 can be geometrically subdivided into two sleeve halves 7a, 7b, wherein a longitudinal section plane M, which in this case comes to lie centrally with respect to the sleeve 7, geometrically separates the two sleeve halves 7a, 7b. The sleeve halves 7a, 7b thus have approximately the shape of pipe shells. Correspondingly, viewed geometrically, the longitudinal axis L lies on the longitudinal section plane M, so that consequently the longitudinal section plane M at the same time the plane of the drawing FIG. 7 and the FIG. 8 is.

In the ready-made cable, the sleeve 7 encloses the shield 4, so that the shield 4 bears against the support clamp 5 both on the radially inner side of the support clamp 5 and on the radially outer side of the support clamp 5.

Due to the slightly smaller radius r of the saddle 22.1, 22.2 of the second Crimpeinsatzpaars 20 creates a constriction in the second section 11, or has the crimped sleeve 7 in the second section II a smaller diameter.

Crimping has produced crimp burrs 7.1 to 7.6 in the sleeve 7, so that the sleeve 7 within the first and third axial sections I, III in the first sleeve half 7a each have two crimp burrs 7.1, 7.2; 7.5, 7.6. In the second sleeve half 7b, the sleeve 7 in the first and third axial section I, III crimpgratfrei configured, ie on the inside continuously concave, so that there was a uniform running largely without geometric disturbances pressing the screen. Furthermore, the sleeve 7 is configured crimp-free within the second axial section II in the first sleeve half 7a and has two in the second half-sleeve 7b Crimp burrs 7.3, 7.4 up. In the exemplary embodiment shown, the crimp burrs 7.1, 7.2 in the first section I, the crimp burrs 7.3, 7.4 in the second section II and the crimp burrs 7.5, 7.6 in the third section III are spaced apart from each other at a central angle β about the longitudinal axis L. The relevant central angle β is 120 ° here. The central angle is to be understood as the midpoint angle about a point on the longitudinal axis L within the relevant section I, II, III. Of course, the most important central angle is the shortest distance and not the complementary angle (in this case 240 °) with respect to the 360 ° circumference. The sleeve half 7a is continuously convex on its outer side in the second section II and has there the radius r, while the sleeve half 7b in the first section I and in the third section III on its outside is designed to be continuously convex and in these sections I, III the Radius R has. Due to the special design of the crimp an excellent electrical connection between the screen 4 and the sleeve 7 is achieved. In addition, an increased mechanical tensile strength is observed.

The cable designed in this way is used, for example, in vehicles for the transmission of RF signals (high-frequency signals). In particular, the cable for producing a so-called FAKRA connector (FAKRA: Fachkreis-Automobil) can be used, wherein the fitting 8 according to the FIGS. 1 and 5 serves for the positionally correct attachment of a secondary locking. Due to the high data transfer rates, z. B. 480 Mbit / s, occur in the cable high voltage frequencies, on the order of 40 MHz, for example. It has now been found that a corresponding cable in conventional construction in operation causes relatively high emission levels. In particular, the high emission levels in the on-board electronics of a vehicle can cause disturbances, which must be avoided under all circumstances, especially in the case of safety-relevant functions of the on-board electronics. Due to the design of the cable, which has now been developed, an extremely good EMC-tightness is achieved, so that radiation levels of the cable in the area of the connector or the sleeve 7 are greatly reduced.

Claims (8)

1. Cable for transmitting RF signals, comprising a shield (4), at least one core (2) and an electrically conductive sleeve (7), wherein the sleeve (7) has a longitudinal axis (L) and
   can be geometrically subdivided by a longitudinal sectional plane (M) into a first geometric sleeve half (7a) and a second geometric sleeve half (7b), characterized in that the sleeve (7) also has a first section (I) and a second section (II),
   wherein the sections (I, II) are arranged offset in relation to one another in the direction of the longitudinal axis (L),
   wherein the sleeve (7) further surrounds the shield (4), and the sleeve (7) is connected to the said shield by a crimp in such a way that the sleeve (7),
   within the first section (I), has at least one crimp ridge (7.1, 7.2) in the first sleeve half (7a) and is designed without a crimp ridge in the second sleeve half (7b), and,
   within the second section (II), is designed without a crimp ridge in the first sleeve half (7a) and has at least one crimp ridge (7.3, 7.4) in the second sleeve half (7b).
2. Cable according to Claim 1, wherein
   the sleeve (7) has a third section (III) which is arranged offset in relation to the second section (II) in the direction of the longitudinal axis (L), and
   the sleeve (7), within the third section (III), has at least one crimp ridge (7.5, 7.6) in the first sleeve half (7a) and is designed without a crimp ridge in the second sleeve half (7b).
3. Cable according to Claim 1 or 2, wherein the sleeve (7) has a smaller diameter in the second section (II) than in the first section (I).
4. Cable according to one of the preceding claims, wherein the at least one crimp ridge (7.1, 7.2) has a greater axial extent in the first section (I) than the at least one crimp ridge (7.3, 7.4) in the second section (II).
5. Cable according to one of the preceding claims, wherein the crimp ridges (7.1, 7.2, 7.3, 7.4) are spaced apart from one another at a centre angle (β), which is less than 150°, in particular less than 135°, around the longitudinal axis (L).
6. Cable according to one of the preceding claims, wherein the outer face of the sleeve half (7a) without a crimp ridge in the second section (II) and/or the outer face of the sleeve half (7b) without a crimp ridge in the first section (I) are/is designed to be continuously convex.
7. Cable according to one of the preceding claims, wherein the cable has four cores (2) which are twisted together.
8. Cable according to one of the preceding claims, wherein the cable has an electrically conductive protective clip (5) in the first section (I) and in the second section (II), wherein the shield (4) bears against the protective clip (5) both radially on the inside and radially on the outside.

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