Cable and method for the production thereof

Abstract

A cable, which extends in a longitudinal direction, has a cable core and a cable jacket. The cable jacket is extruded around the cable core. The cable is distinguished by the fact that the cable jacket has a plurality of chambers and, overall, is designed, in particular, in the manner of a hollow profile, and by the fact that a functional material different from the material of the cable jacket is introduced within at least one of the chambers. The functional material is preferably a flame proofing agent, but numerous other materials and, in general, functional elements are also conceivable. We further describe a method for producing the cable.

Claims

1. A cable that extends in a longitudinal direction, the cable comprising: a cable core; a cable jacket extruded around said cable core, said cable jacket having a plurality of chambers formed therein; and a functional material different from a material of said cable jacket disposed within at least one of said chambers; wherein said functional material is a multi component system having at least two different materials, wherein said different materials are arranged in different chambers of said plurality of chambers and said different materials are materials that react with one another upon contact to form a filling with at least one property differing from a corresponding property of each of said different materials.

2. The cable according to claim 1, wherein said different materials are configured to produce said filling as an expanding filling upon reacting with one another.

3. The cable according to claim 1, wherein at least one of said chambers is configured to transport an operating medium.

4. A method for producing a cable, the method comprising: providing a cable core; extruding a cable jacket onto the cable core, and forming the jacket with a plurality of chambers; and completely filling at least some of the plurality chambers with a functional material during or after the extruding step, to thereby form a cable according to claim 1; wherein said functional material is a flame proofing agent; and wherein said functional material is a multi component system having at least two different materials, wherein said different materials are arranged in different chambers of said plurality of chambers and said different materials are materials that react with one another upon contact to form a filling with at least one property differing from a corresponding property of each of said different materials.

5. The method according to claim 4, which comprises: cooling the cable after extruding the cable jacket, and, during the cooling process, filling at least one of the chambers or all of the chambers, with the functional material being a flame proofing agent.

6. The method according to claim 5, which comprises cross-linking the flame proofing agent after the step of filling the chamber or the chambers.

7. The method according to claim 5, wherein the cable jacket is manufactured from a material which is processed at a given processing temperature, and wherein the flame proofing agent has a decomposition temperature which is lower than the given processing temperature.

8. The cable according to claim 1, wherein at least one of said at least two different materials is a flame proofing agent disposed within and completely filling at least one of said different chambers.

9. The cable according to claim 1, wherein all of said plurality of chambers of said cable jacket are completely filled with said functional material.

10. The cable according to claim 1, wherein said flame proofing agent is composed of a pulverulent solid and of a process material.

11. The cable according to claim 10, wherein said process material is cross-linked to render said flame proofing agent a solid flame proofing agent.

12. The cable according to claim 1, wherein said flame proofing agent has a given decomposition temperature and said cable jacket is formed of a material which has a processing temperature that is higher than the decomposition temperature.

13. The cable according to claim 1, wherein said flame proofing agent comprises aluminum hydroxide embedded in a process material, and said cable jacket is manufactured from polypropylene.

14. The cable according to claim 1, wherein said chambers are uniformly distributed in a circumferential direction about said cable core.

15. The cable according to claim 1, wherein said chambers are formed as ring segments in a cross section transverse to the longitudinal direction of the cable.

16. The cable according to claim 1, wherein the cable is formed with a first end and a second end and each of said chambers extends continuously from said first end to said second end.

17. The cable according to claim 1, wherein said functional material is a physically activatable material arranged within said at least one of said chambers.

18. The cable according to claim 1, wherein said functional material is a shock-absorbing fluid arranged within said at least one of said chambers.

19. The cable according to claim 1, wherein said functional material is a phase change material arranged within said at least one of said chambers.

20. The cable according to claim 1, wherein said functional material is a repair material arranged within said at least one of said chambers to form a self-healing cable.

21. The cable according to claim 1, wherein said different materials react with one another upon contact by chemically reacting with one another upon contact.

22. The method according to claim 4, wherein said different materials react with one another upon contact by chemically reacting with one another upon contact.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) Illustrative embodiments of the invention are explained in greater detail below by means of a drawing, in which, of the figures, each of which is schematic:

(2) FIG. 1 shows the extrusion of a cable jacket for a cable,

(3) FIGS. 2a-2c each show one variant of the cable in a cross-sectional view,

(4) FIGS. 3a, 3b show a cable with an expanding or expanded filling, and

(5) FIG. 3c shows the cable from FIG. 3a in a cross-sectional view.

DESCRIPTION OF THE INVENTION

(6) A preferred production method for a cable 2 is shown in highly schematized form in FIG. 1. The cable 2 has a cable core 4, which is fed to an extruder 6 as a semifinished product and, in the process, to an extrusion head 7. By means of said extrusion head, a cable jacket 8, made from polypropylene for example, is extruded onto the cable core 4. Three illustrative embodiments of the cable 2 are shown in FIGS. 2a to 2c, in each case in a cross-sectional view. There, it can be seen, first of all, that the cable jacket 8 has a number of chambers 10, which extend in a longitudinal direction L along the cable 2 and are furthermore of continuous design here. After the extrusion head 7, the cable 2 is transferred to a water bath 12 for cooling. In a variant which is not shown, the cable 2 is alternatively or additionally passed through a sizing unit, which ensures that the chambers 10 do not collapse during subsequent cooling and that the cable jacket 8 maintains the envisaged shape.

(7) In FIG. 1, the chambers 10 are filled with a functional material M shortly after the extrusion of the cable jacket 8. This material is fed directly to the extrusion head 7. The extrusion head 7 furthermore has a number of capillaries 13, which extend in the delivery direction, i.e. in longitudinal direction L, and serve as a supporting contour for the chambers 10. At the same time, the capillaries 13 have a shaping effect. The functional material M is then first of all passed through the capillaries 13 and is introduced into the chambers 10 from the capillaries 13 only at a distance A after the extrusion head 7 in the delivery direction. At this point, the cable jacket 8 has cooled down sufficiently, and therefore the functional material M does not run the risk of decomposition.

(8) As an alternative, air or some other supporting medium is used first of all and then, in particular after cooling, the chambers 10 are filled with a functional material M. In this variant, which is not shown, a cable 2 formed with hollow chambers is therefore formed as an intermediate. In principle, this can also be used as an end product. In a variant which is not shown, the chambers 10 are alternatively or additionally equipped with a pre-produced functional element.

(9) In the variant shown in FIG. 2a, the cable has a plurality of chambers 10 in the form of ring segments, which are arranged uniformly in a circumferential direction around the cable core 4 in the cable jacket 8. Toward the cable core 4, the chambers 10 in FIGS. 2a and 2b are delimited by an inner jacket section 14 and, toward the outside, they are delimited by an outer jacket section 16 and, with respect to one another, are delimited by webs 18. In the illustrative embodiment in FIG. 2c, however, an inner jacket section 14 is lacking, and therefore the webs 18 and the chambers 10 extend as far as the cable core 4.

(10) The chambers 10 are preferably filled with a flameproofing agent M. In principle, however, there are numerous possibilities in the selection of the equipment or filling of the chambers 10. As an alternative or in addition, the material M is, for example, a shock absorbing fluid, a light-transmitting material, e.g. as a functional element in the form of an optical fiber, a phase change material or a repair material.

(11) In FIG. 2a, the cable core 4 is a simple wire 20, having a conductor 22 surrounded by insulation 24.

(12) In the variant shown in FIG. 2b, the cable 2 likewise has a plurality of uniformly distributed chambers 10, but these are shaped elliptically here. Here, the cable core 4 is a line 26 comprising a plurality of wires 20.

(13) FIGS. 3a and 3b show a variant of the cable 2 in a side view, in which two different materials M1, M2, which form an expanding filling in a mixing operation, are arranged in the chambers 10. In FIG. 3a, the cable 2 is first of all passed with clearance through a passage 28. The cable jacket 8 is then cut or pierced slightly as illustrated, for example, or, as shown in the cross-sectional view in FIG. 3c, slightly compressed, with the result that the web 18 between two chambers 10 is destroyed and the two materials M1, M2 in the adjacent chambers 10 are mixed, chemically react and finally form the expanding filling. This then has the effect that a thickened portion 30 in the form of an enlarged throat is formed on the cable 2, as shown in FIG. 3b. The passage 28 is then closed in an optimum manner and the cable 2 is seated with optimum sealing in the passage 28.

LIST OF REFERENCE SIGNS

(14) 2 cable

(15) 4 cable core

(16) 6 extruder

(17) 7 extrusion head

(18) 8 cable jacket

(19) 10 chamber

(20) 12 sizing unit

(21) 14 inner jacket section

(22) 16 outer jacket section

(23) 18 web

(24) 20 wire

(25) 22 conductor

(26) 24 insulation

(27) 26 line

(28) 27 passage

(29) 30 thickened portion

(30) A distance

(31) L longitudinal direction

(32) M functional material

(33) M1, M2 material