WO2007009272A1

WO2007009272A1 - High-security cable

Info

Publication number: WO2007009272A1
Application number: PCT/CH2006/000292
Authority: WO
Inventors: Walter NÜESCH
Original assignee: Cortex Hümbelin Ag
Priority date: 2005-07-21
Filing date: 2006-06-01
Publication date: 2007-01-25
Also published as: US20080223016A1; ATE461316T1; EP1904680B1; EP1904680A1; DE502006006459D1

Abstract

According to the invention, a high-security cable may be produced which can support extremely high loads within a relatively short period of time, by means of a cable made from a mixture of various synthetic yarns or synthetic yarns and metal wires. Said synthetic yarns and metal wires shall be present in the cable in three different production forms, namely in one form as twisted or untwisted yarns or wires, in a second form as twists and in a third form as cords. The twists and the cords are produced from twisted or untwisted yarns or wires. According to the invention, a twist is made from two yarns and a cord from three yarns. Said high-security cables are advantageously applied to automobile racing for the attachment of a wheel to the chassis of the racing car and for the production of security catch cables of application for piste security as temporary avalanche catch nets or temporary falling stone protection nets.

Description

High-security cable

The present invention relates to a high-security rope which is made of a mixture of plastic yarns or of plastic yarns and metal wires.

High security cables are used in various applications. High-security ropes, which are used as safety cords, in particular for connecting a wheel of a race car with its chassis, are particularly known today. Such a safety rope is known from WO 03/048602. The said rope consists of a mixed yarn of filaments with relatively rigid plastic filaments with an elongation to break elongation of 2 to 5% and of relatively elastic plastic filaments with an elongation to break elongation of 12 to 25%. Here, the various plastic filaments are twisted into yarn strands, the yarn strands are twisted calm, while the rope made from these yarn strands is not twisted calm. Such a rope has not only a high tensile strength, but also an increased elongation, whereby an improved energy absorption can be achieved.

- l - Thanks to the corresponding increased energy absorption by the rope itself, not all the energy at full load is transferred directly to the anchorage, which is often the critical point in the overall system.

The well-known safety rope, which is used in Formula 1 racing, may only have a relatively short stretch path for safety reasons to prevent the broken now hanging on the safety rope can hit the cockpit or the head of the driver. However, in other racing vehicles and in other applications, a longer stretch would not only be acceptable but may even be desirable. The Applicant has accordingly further researched in this direction and in particular also sought solutions that allows practically to create a customization of the characteristics.

Considering the so-called "work-to-break-energy" curve of any material, such a curve has in principle the shape of an acute triangle in a coordinate network, where the force F on the abscissa and the elasticity E on the ordinate The tensile strength of the material is reflected in the height of the triangle and the elasticity of the material reflects the inclination of the hypothenuse of the right triangle Material-specific peaks in the entire envelope clearly visible. Depending on the load, this leads to an extremely unfavorable tear behavior.

It is therefore an object of the present invention to provide a high-security rope, which is able to achieve a smoothing of the "work-to-break-energy" curve by its special production, which altogether the absorbable energy is to be increased to break The invention also relates to the use of such a high-security rope for various applications which have not been considered for ropes of this type until today filaments of one or more plastics and wires of one or more metals or metal alloys can be manufactured.

In the drawing, various graphics are shown, which symbolically represent the recoverable effect of the invention. It shows:

Figure 1 is a force expansion diagram for various materials in symbolic representation Figure 2 is another force expansion diagram of a single material consisting of yarn, twisted yarn and cord

FIG. 3 shows a force expansion diagram of a

Hochsicherheitseiles, which is designed according to the invention.

High-security cables are usually made of a single material, usually starting from the expected maximum force that may act on the cable. Only for reasons such as weather resistance, UV resistance, temperature resistance or other requirements specific type has been used mixed two or three different materials. Consequently, they have either limited themselves to textile ropes made of natural and synthetic fibers or made pure metal ropes. Ropes mixed with both fibers and wires are not available on the market.

As schematically illustrated in the force-strain diagram of Figure 1, the various materials referred to herein as Mi, M ₂ , M ₃ or M ₄ have different moduli of elasticity and different load-to-break curves. The corresponding curves represent symbolically mono- or multifilament ropes without Verzwirnung. Such curves have a more or less steep flank, a relatively small maximum plateau to maximum elongation, which leads to breakage.

The Applicant has now determined in a large series of investigations, how these curves change when instead of simple yarn in verzwirnter or in untwisted form to twine or cord further processed. It was found that this form of processing can flatten the slope of the slope curve and depending on the type of processing the maximum power transmission can be maintained during a longer stretch path. In other words, the previously pointed curves, as they are known from Figure 1, can be stretched. As a result, the curves become flatter in that, as the force increases, the strain path also increases, with this occurring both in the initial phase and increasing with the maximum applied force. The total power that such a rope can absorb is represented by the area below the envelope.

Depending on the application, however, it is by no means desirable to obtain a relevant extent even before the maximum force is applied. The object of the invention is seen herein to provide a rope which has as low as possible to reach the maximum application force, however, as far as maximum force is concerned as large as possible Stretching allowed until breakage. This optimizes the maximum recordable power.

From the stress-strain diagram according to FIG 3, an example is now shown in which four different materials symbolized by M ₁ to M ₄ are processed, all of the materials present both in the form of a yarn or wire, as well as in the form of twisting and ultimately also in the form of cord. The presence of these materials in all three forms of processing, although not necessarily all material must be present in all three processing forms, although this certainly represents the most optimal design, a curve can be realized, which can be shown symbolically practically as a rectangle.

Since the definitions of the terms used herein are not internationally uniform, these terms will be defined as they are understood in the present invention. The smallest element is a monofilament or a single wire. Here, the fineness of the wire is not determined. Yarn in the present invention is understood to mean an endless product consisting of several filaments. Here, the yarn can be untwisted or rotated. In analog white, a yarn according to this invention can also be made of a variety consist of fine metal wires. These metal wires can be turned or untwisted.

In the invention, a twine is understood to mean a product which consists of two twisted yarns. Each yarn can be S- or Z-twisted. This is understood by the S-twist a left twist and under the Z-twist a right-handed twisting.

Under a cord is understood in the present invention, a product in which at least three yarns are twisted into a cord. It has been found that advantageously a cord is used, which consists of three yarns, wherein at least one yarn is wound differently than the other two yarns. Thus, one will produce cords made of, for example, two S-twisted yarns and one Z-twisted yarn, or two Z-twisted yarns and one S-twisted yarn.

The individual yarns not only vary in the direction in which they are twisted, but they also differ in the number of revolutions per meter. This figure can vary in size from about 30 revolutions per meter to a maximum of 600 revolutions per meter. While the S-twist or the Z-twist can be used regardless of the type of material, the variation is the

- H - Revolutions per meter depends on various factors, such as the stiffness of the materials and, of course, on the effect to be achieved. In principle, the lower the twist, the lower is the stretch path to break, but it should be additionally taken into account that with a very high number of revolutions per meter, although the stretch increases to break, but that the maximum force to break itself reduced. The latter applies in particular to yarns which are made entirely of metal or to yarns which contain a metal part.

As already mentioned, cords consisting of three yarns are advantageously used in the invention. Within a cord, the variation of the yarns used therein, both in terms of the properties of the materials and in terms of the number of revolutions per meter should not be too strong. From the table below you can see different cords and their composition of different yarns, with only the information on the rotations of the yarns are given, but not their material composition.

With regard to the materials coming into question here, one can essentially ignore the pure natural fibers. In addition to the known carbon fibers with a tensile strength of 20 cN / dtex or the much more elastic m-aramid fibers, which have a tensile strength of 4.7 cN / dtex, come here of course in question. The mentioned elastic m-aramid fibers can also be combined very well with the relatively rigid p-aramid fibers, which have a tensile strength of 19 cN / dtex. The very modern PBO fibers, which even have a tear strength of around 37 cN / dtex, have a particularly high tear resistance. Ropes made from such highly tear-resistant fibers are able to absorb tensile forces that often far exceed the forces normally encountered. Nevertheless, even such high-security cables, which are made of such high-tensile materials, extremely problematic in use. The low elastic elongation to break extension of only 1.5 to a maximum of 3.5% limits their use. Wherever very high forces can occur for a relatively short time, the cables must be able to absorb part of the energy via the expansion, since otherwise the short-term, enormously high forces that occur only lead to the destruction of the attachment points of the cables. Even if these attachment points can in many cases be dimensioned much stronger than the ropes themselves, the problems occur according to experience at the fixing points. In order to increase the deformation work that can be done by the rope, in particular the admixture of metal wires, which may be integrated either in the yarn or in the cord, in particular by a so-called core spinning method, wherein the metal wire or in the Center while the plastic yarns are running around it. In the case of the metal wires of interest here, of course, various steel wires come into question, but in particular also wires made of nickel or austhentisehen Niekel chrome alloy have proven. Austent nickel-chromium alloys were twisted in the form of wires less than 0.5 mm in diameter and further processed into a rope of 12 to 13 mm in diameter. Such a rope with a length of about 600 mm allows the transmission of a maximum force of 57.8 kN. The work-to-break work also amounted to 10'000 Nm.

It is essential according to the present invention, the fact that the rope must consist of three different proportions, namely on the one hand from yarns, on the other hand from twisting and thirdly from cords. Whereby at the same time of every share of material, this material should be present both as a yarn as a twist and as a cord. This is the only way to ensure that the three different expansion areas of the same material are used.

- lo - Only thanks to the combination of all three processing stages, the maximum elasticity of the material is fully utilized. Although the processing of metal wires in the high-security rope according to the invention is not mandatory, such wires have proved to be extremely advantageous for covering certain strain ranges. If the high-security rope contains fractions of p-aramid fibers, m-aramid fibers or PBO fibers, the proportion of these fibers which have a tensile strength of more than cN / dtex should consist more of yarn and twist, but to a lesser extent than pure cords.

The use of such inventive high-security cables is hardly suitable for ropes that only need to transmit a relatively steady very high tensile force. However, wherever extremely high peak loads of a high-security cable occur, the high-security cables according to the invention can be used. In particular, tests have proven that such safety cords are suitable for use in motor racing for connecting a wheel to the chassis of the racing car. In such a use, it has been shown that it makes sense to make the inventive rope so that several turns are formed into parallel loops, so that at least one open loop is formed at both ends.

- II - Another field of application of these inventive ropes is that they can be used to make safety leashes that can be attached along ski runs and in particular along racetracks of alpine sports.

High-security ropes can only meet their required safety standards if they are used under manageable conditions. Accordingly, they are hardly suitable for use in perennial rockfall protection structures or avalanche protection structures. The prevailing environmental influences would over time also show their effect on the high-security cable. On the other hand, the high-security cables according to the invention can advantageously be processed into networks which can serve as temporary avalanche safety nets. Accordingly, such ropes can also be processed into networks as temporary rockfall protection nets.

Claims

claims

1. high-security rope, which is made of a mixture of plastic yarns or of plastic yarns and metal wires, characterized in that the rope made of a first portion of untwisted or verzwirnter yarns or untwisted or verzwirnter yarns and wires, a second portion of twine made of KunstStoffgarnen or from Plastic yarns and metal wires - as well as a third portion of cord made of twisted yarns, which are made of plastic yarns or of plastic yarns and metal wires.

2. High security rope according to claim 1, characterized in that each KunstStoffgarnsorte is present in each share.

3. High security rope according to claim 1, characterized in that each metal wire type, if present, is present in each portion.

4. High-security rope according to claim 1, characterized in that the rope at least one yarn Fibers of the group of carbon fibers comprising p-aramid fibers, m-aramid fibers and PBO fibers.

5. High-security rope according to claim 1, characterized in that the cable comprises wires of nickel or of an austenitic Ni-Cr alloy.

6. high-security rope according to claim 1, characterized in that the threads are each made of an equal proportion of S- and Z-twisted yarns.

7. High-security rope according to claim 4, characterized in that the proportion of yarns with a tensile strength of more than 10 cN / dtex predominantly occur in the first and second portions.

8. high-security rope according to claim 1, characterized in that the likes of a twist of min. 30 U / m and max. 600 U / m.

9. High-security rope according to claim 1, characterized in that the metal wires are integrated in the coverspin method in the yarn.

10. Use of a high-security rope according to one of claims 1 to 8, characterized in that this is used as a safety rope for connecting a wheel of a race car with the chassis.

11. Use of a high-security rope according to one of claims 1 to 8, characterized in that this is used as a safety rope for connecting a wheel of a race car with the chassis, wherein the high security rope is formed into several turns of parallel closed loops, so that at least two ends each one open flap is formed.

12. Use of a high security rope according to one of claims 1 to 8, characterized in that from this networks are knotted, which serve as safety nets along ski slopes.

13. Use of a high-security rope according to claim 11, characterized in that the nets serve as temporary avalanche fishing nets.

14. Use according to claim 11, characterized in that the nets serve as temporary rockfall protection nets.