WO2000013940A1

WO2000013940A1 - Cabling element

Info

Publication number: WO2000013940A1
Application number: PCT/EP1998/005697
Authority: WO
Inventors: Wolfgang Nolden; Holger Heidemann; Norbert Fink
Original assignee: Felten & Guilleaume Aktiengesellschaft
Priority date: 1998-09-09
Filing date: 1998-09-09
Publication date: 2000-03-16

Abstract

The present invention relates to a two- or three-dimensional cable bundle (100) for blocks of opto-electronic components mainly for use in vehicles. The cable bundle comprises a small metallic tube (10) which has a reduced flexural strength and comprises data transmission elements (80) arranged therein, mainly optical fibres made of polymeric fibres, wherein said tube comprises, according to its dimensions, a plurality of straight sections and at least one curved section (21). In order to increase the flexural strength of this small tube (10), at least one curved section (21) is provided partially or entirely with a coating.

Description

Wiring element description

The invention relates to a two- or three-dimensionally shaped element for wiring optical or optoelectronic assemblies (so-called cable harness), in particular in vehicles.

It is known to use cable harnesses in vehicles as a bundle of a larger number of flexible cables which, depending on the application, can also be assembled at their ends with plugs or other connecting elements. It is also known - especially when laying cables in devices that relatively rigid lines are lengthened to a certain length and pre-bent or bendable at certain points and inserted into devices or vehicles and connected to the connection points.

For the installation in motor vehicle bodies, a cable harness made of plastic has been proposed, which in parts consists of very strong material. A large number of lines can be drawn into such parts, which are packed therein in a stationary and watertight manner (DE 37 10 642 A1). In another wiring harness, wire bundles are formed, for example, by winding the wires with a tape. This wiring harness obtains the necessary dimensional stability from a shaping reinforcing element (DE 40 26 718 A1) which is introduced into the core bundle. Yet another wiring harness for a complete wiring harness is designed so that it consists of compact parts that can be folded together. The advantage lies in the collapsibility for transport to the assembly site on the assembly line (DE 41 38 714 A1). Special molded or reinforcing parts are therefore introduced or provided in order to achieve sufficient stability for robot assembly. The disadvantage of these wire harnesses is particularly that the reinforcing parts increase the weight and / or the contour of the wire harnesses.

Optical fibers made of polymer material have also been proposed for use in motor vehicle technology (VDI series plastics technology, 1993, plastics in automotive engineering, pp 109-146). Cable harnesses with one or more plastic fiber optic cables also have the disadvantage of low bending stiffness.

It is the object of the invention to propose a light, two- or three-dimensionally shaped element for the wiring of data transmission cables which is prefabricated and can be used for assembly. The essence of the invention consists in partially or completely encasing at least one metallic tube of low bending stiffness with at least one internal data transmission element, which comprises straight sections and at least one bow section, in order to increase the bending stiffness. The stiffening jacket should preferably be made of plastic. With the invention, two- or three-dimensionally shaped elements can be formed, which can also be used directly in complicated installation situations, without having to make bends, cuts or other adjustments.

Thin stainless steel tubes are preferably proposed which, depending on the inner diameter, contain a certain number of data transmission elements (one or more optical waveguides made of glass or plastic). Thin stainless steel tubes can be produced in any lengths using known manufacturing processes (for example using a process of EP 0 299 123 A1). Copper, aluminum alloy or steel can also be used as a further material of the tubes; the tubes can also be designed as corrugated shells. Because of the small wall thickness (typically 0.16 to 0.4 mm) and the small diameter (typically 1.5 to 6 mm), the above-mentioned tubes do not have sufficient inherent rigidity in longer lengths. The rigidity that is necessary for transport packaging, transport and installation is only produced by the invention. The casing stabilizes both the low inherent rigidity and against elastic restoring forces.

The possible areas of application are varied, preferably devices, vehicles or aircraft. Depending on the diameter, the cabling element can contain one or a few plastic optical fibers (polymer optical fibers, POF) or up to 100 glass optical fibers. Depending on the suitability, optical waveguides can be used without a secondary coating or those which are coated with a coating or cladding layer and / or with a layer which increases the reflection. The subject matter of the application can also be used for plastic optical fibers which have been produced in a manufacturing process in which the plastic is 'filled' directly into the metal shell. Such a manufacturing process has the advantage that one work step is saved.

It is also proposed to embed at least two tubes in the manner of a multiple in a casing. The arc sections are preferably bent with a radius that is greater than the critical bending radius of the data transmission elements.

Furthermore, it is proposed to assemble the data transmission elements with connecting elements at at least one end of the cabling element. Every type of optoelectronic connection element is considered, such as plugs, rigid or rotatable couplings, LED couplers, switches or sleeves.

The data transmission elements can be embedded in the tube with filling compound (for example petrolatum).

The sheathing is said to increase the bending stiffness. Various measures are possible for this. The sheathing can be formed from plastic, from a wire or foil bandage, as a braid sheath or stranded strand. A wire bandage can be created by roping with one or more wires. For different applications, the sheathing can be made hard to increase rigidity or, if vibration damping is required, rather soft. The bending stiffness does not have to be extremely increased in every case. Applications are possible in which residual bendability is desired, so that the cabling element still has a certain deformability for subsequent adaptation to certain positions or radii. Any method of encasing elongated objects known to the person skilled in the art is proposed as the encapsulation method without having to go into details.

Plastics, wires or foils of different quality can be used as the sheathing. Cross-linked polyethylene (VPE) or synthetic resin are suitable as hard plastics. Rubber is suitable as a soft material. A wire or a foil bandage can be covered with plastic. The plastic sheath can also have an insulating function, so that applications are conceivable in which the metallic tube is used as an electrical conductor (for example for electrical signaling) under a plastic insulation.

To accelerate the installation process, the cabling element can be provided with at least one fastening element, for example as a clamp or tab. For certain applications, fasteners can be formed on the metallic tube as a ground connection, so that no potential difference to the housing of the vehicle can arise. At least one point on the surface of the cabling element can be marked. Such markings can indicate the direction of connection, the type or number of optical fibers or the type of connection to the next element.

The cross section of the cabling element can be round or polygonal.

Embodiments of the invention are shown in the figures. They show in detail: FIG. 1 a schematic, spatial representation, FIGS. 2a and 2b each a cross section with casing, FIGS. 3 to 6 four types of connecting elements, FIGS. 7a and 7b two cross sections (schematic) and FIG. 8 shows a cross section of a double tube.

1 shows a cabling element 100 running in three spatial directions (x, y, z). The lengths of the straight sections and those of the arches and the curvature (radius and direction) of the arches are generally specified by the dimensions of the built-in device or the vehicle. With these dimensions (and also assembled with plugs, etc.), each cabling element can be manufactured in the factory and delivered to the installation site. No further adjustments, changes or interventions on or in the cabling element are made during assembly. 1 contains a metallic tube 10 with three loosely emerging optical waveguides 80 and a sheath 20 extending almost over the entire length. Freely emerging optical fibers can be connected (spliced) as desired. Pre-assembly with a connecting element should, however, be the rule for most applications. The

Arch elements 21 have a radius of curvature R which is not less than the critical bending radius of the inner optical waveguide 80. One end of the cabling element is terminated with a plug 30.

FIG. 2a shows a tube 10 with a jacket 20 with a circular cross-section with many optical fibers 80 of small diameter. Fig. 2b shows an example of the use of polymeric optical fibers 80 'with fiber sheathing 82. Such plastic fibers made of materials such as polyacrylic or polymethyl methacrylate have diameters of 0.3 to 3 millimeters, so that (as shown in Fig. 2b ) only have a few fibers in a tube. Figures 3 to 6 show connecting elements for the termination of a tube. Reference numerals 30, 31, 32 and 33 show a plug (30), a coupling (31), a flared protective cap (32) - to avoid sharp metal edges - and an optical switch (33). Furthermore, it is indicated that the optical waveguide (s) 80 lie in the tube with excess length, which results in their helical position. 6 shows a clamp 40 with which the tube can be attached or grounded. If the clamp 40 is used for earthing, the clamp must be metallic and in electrical contact with the tube.

FIGS. 7a and 7b schematically show two cross sections (rectangle and square) of a tube 10. In Fig. 8 two tubes are shown as' twin '100' side by side in a jacket. The two tubes 10, 10 'can lie straight next to one another or can be stranded together. The existing gussets 22 can be filled with plastic.

Claims

claims

1. Two- or three-dimensionally shaped element (100) for the wiring of assemblies - in particular in vehicles, consisting of at least one metallic tube (10) of low bending stiffness with at least one internal data transmission element (80) - in particular optical waveguide, which according to the specification has straight sections and at least comprises an arc section (21), the at least one tube (10) and / or at least one arc section (21) being partially or completely encased to increase the bending rigidity.

2. Cabling element according to claim 1, characterized in that the arc sections (21) are bent with a radius (R) which is greater than the critical bending radius of the data transmission elements (80).

3. Cabling element according to claim 1 or 2, characterized in that several tubes (10) are sheathed in parallel with each other.

4. Cabling element according to one of the preceding claims, characterized in that the data transmission elements (80) are assembled at least at one end of the cabling element (100) with connecting elements (30).

5. cabling element according to one of the preceding claims, characterized in that at least one data transmission element (80) is embedded with filling compound.

6. Cabling element according to one of the preceding claims, characterized in that the casing (20) is made of plastic.

7. Cabling element according to one of claims 1 to 5, characterized in that the casing (20) is a wire bandage.

8. Cabling element according to one of claims 1 to 5, characterized in that the casing (20) is a foil bandage.

9. Cabling element according to one of claims 7 or 8, characterized in that the wire or foil bandage is coated with plastic.

10. Cabling element according to one of the preceding claims, characterized in that the material of at least one tube (10) is stainless steel.

11. Cabling element according to one of the preceding claims, characterized in that the cabling element (100) is provided with at least one fastening element (40).

12. Cabling element according to claim 11, characterized in that the fastening elements (40) is designed as tabs or as an earth connection.

13. Cabling element according to one of the preceding claims, characterized in that at least one point on the surface of the cabling element (100) is marked.