Contact wire of a power rail and power rail

Abstract

A conductor rail of an overhead line comprising at least two clamping arms and a contact wire for contacting a pantograph of a rail vehicle, wherein the contact wire is made of aluminum or an aluminum alloy, wherein each clamping arm engages in a groove of the contact wire and thereby holds it clampingly, wherein the clamping arms are made of aluminum or an aluminum alloy.

Description

[0001] The present invention relates to a contact wire according to the preamble of claim 1 and a conductor rail.

[0002] Stranded wires, so-called ACSR wires, which can be used as contact wires, are known from DE 697 01 817 T2. These wires consist of a plurality of individual wires twisted together. Corresponding material phase transitions and possibly air inclusions are associated with this type of wire.

[0003] A contact wire for an overhead line is known from JP S63 - 53 132 A.

[0004] The function and construction of a contact wire and a conductor rail are known, for example, from EP 3 702 204 A1. This is described, among other things, in Fig. Figure 1 shows a typical conductor rail. In this type of application, a contact wire with particularly high conductivity is typically used. Common materials used in this field are copper or a copper alloy.

[0005] The contact wire serves as the contact point for a current collector, also called a pantograph. Copper contact wires generally allow for satisfactory current transmission to the pantograph. A disadvantage of using such a contact wire is its high weight, which complicates installation. This is done by unrolling the contact wire from a spool that usually weighs several tons.

[0006] The weight of the contact wire determines both the construction method and the number of supports for the overhead line per kilometer of track, as well as the sagging of the wire.

[0007] Starting from EP 3 702 204 A1 as the generic prior art, the object of the present invention is to provide a contact wire which reduces the aforementioned disadvantages.

[0008] The present invention solves the problem by providing a contact wire with the features of claim 1.

[0009] A conductor rail of an overhead line according to the invention comprises at least two clamping arms and a contact wire for contacting a pantograph of a rail vehicle, wherein the contact wire is made of aluminium or an aluminium alloy, wherein each clamping arm engages in a groove of the contact wire and thereby holds it clampingly, wherein the clamping arms are made of aluminium or an aluminium alloy.

[0010] In the context of the present invention, "constructed" means that the contact wire can be made of the light metal or the light metal alloy. However, advantageously and according to the invention, particularly with regard to conductivity, the contact wire consists of a uniform material across its entire cross-section.

[0011] In the scientific community, a "light metal" is defined as a metal with a density of less than 5 g / cm³. 3 This definition is known. This definition also applies within the scope of the present invention.

[0012] A “light metal alloy” consists mainly, i.e., more than 50 wt.%, preferably more than 90 wt.%, of the corresponding light metal, in particular aluminum.

[0013] The significantly reduced weight of the lightweight metal makes the installation of the contact wire easier and allows for a reduced structural effort in supporting the contact wire, for example a reduction in support and holding segments, posts and the like.

[0014] The use of a light metal as a contact wire according to the invention is surprising insofar as the known light metals, namely aluminum, have a significantly lower conductivity than copper. Nevertheless, extensive feasibility tests have shown that a material substitution is possible and that the contact wire exhibits sufficient mechanical strength and chemical resistance for the aforementioned application.

[0015] Further advantageous embodiments of the invention are the subject of the dependent claims.

[0016] Advantageously, the contact wire can be designed as a grooved contact wire with two grooves opposite each other on the sides of the contact wire, preferably in a V-shaped design.

[0017] Furthermore, the contact wire may have marking grooves which have a different groove sequence than already known marking grooves, e.g. for the material description of copper.

[0018] According to the invention, the contact wire is made of aluminum or an aluminum alloy. As tests have shown, aluminum, and also corresponding aluminum alloys with aluminum as the main component, possess sufficiently good conductivity for use as a contact wire.

[0019] Additional sealing, especially of the contact points with other components of the conductor rail, against environmental influences such as frost, rain, etc., is advantageously achieved if the contact wire is greased at least partially or preferably completely over its entire length and circumference.

[0020] The aluminum alloy is specifically designed as an aluminum-magnesium-silicon alloy, preferably with an aluminum content in the alloy of more than 97 wt.%, and particularly preferably more than 98 wt.%. This allows the material properties to be further modified to suit the intended application while maintaining the conductivity of the aluminum.

[0021] The alloy can contain at least 0.18 wt.%, preferably between 0.2 and 0.6 wt.%, silicon, and at least 0.4 wt.%, preferably between 0.45 and 0.9 wt.% magnesium, wherein the magnesium content is always higher than the silicon content. Such an alloy can further develop increased hardness and thus wear resistance during operation through the deposition of Mg₂Si upon heating.

[0022] Even when using an aluminum alloy or another light metal or light metal alloy, the contact wire should have an electrical conductivity of at least 2.1-3.4 * 10⁻⁶ to maintain its functionality. 7 S / m at 23°C. Corresponding conductivity tests can be carried out on various alloys and light metals to identify suitable materials.

[0023] Due to its reduced conductivity compared to a copper wire, a cross-sectional area of ​​more than 135 mm² is recommended for the optimal function of a contact wire made of light metal, especially aluminum or an aluminum alloy. 2 , preferably between 140-160 mm 2 , especially 150 mm 2 + / - 3 mm.

[0024] In a preferred embodiment, the V-shaped grooves are arranged on a first half of the contact wire. The second half can have the contact surface for the current collector and be partially spherical.

[0025] Choosing aluminium as a softer material compared to copper allows for greater and more uniform contact with the clamping arms, as the flanks of the grooves fit better and more closely against the clamping arms, thereby reducing the risk of water ingress at the contact points.

[0026] Advantageous embodiments of the busbar according to the invention are the subject of the dependent claims.

[0027] In a particularly advantageous embodiment of the invention, the clamping arms for holding the spring wire are made of aluminum or an aluminum alloy, preferably of a material analogous to that of the contact wire. Besides the absence of a potential difference, this design also results in uniform thermal expansion due to temperature fluctuations between the clamping arms and the contact wire. This achieves a watertight connection at contact points while maintaining resistance to temperature fluctuations, e.g., during the alternating hot and cold phases of day and night.

[0028] The invention is explained in more detail below with reference to the accompanying figures. These show: Fig. 1 a schematic representation of the structure of a busbar according to the invention; and Fig. 2. A cross-sectional view of a contact wire.

[0029] The figures use identical technical elements with the same reference symbols and describe them only once. The figures are purely schematic and, above all, do not represent the actual geometric relationships.

[0030] It will be on Fig. Figure 1 refers to a track 2 extending in a direction of travel 1 or longitudinal direction 1, with a track 3 on which an electrically driven train (not shown) can move, guided by the track 3. For the electrical power supply of the train, a conductor rail 4, also extending in the longitudinal direction 1, is arranged at a height above the track 3 (not further referenced), from which the train can draw electrical current in a manner known per se by means of a pantograph (not further shown).

[0031] The power rail 4 is suspended from a support which is located in the Fig. Figure 1 shows an exemplary ceiling 5. The ceiling 5 could, for example, be part of a tunnel or a bridge. The conductor rail 4 can be held at a suspension distance 6 from the ceiling 5 by means of suspension devices (not shown).

[0032] In Fig. Figure 1 shows an enlarged view of profile 7 of the busbar 4.

[0033] Viewed in profile 7, the conductor rail 4 is axially symmetrical about a profile axis 8. The profile axis 8 runs parallel to a vertical direction 9 of the track 2. Viewed in the vertical direction 9, a transverse arm 10 is located on the upper side of the conductor rail 4. From this transverse arm 10, two tension arms 12 extend in a transverse direction 11, perpendicular to the longitudinal direction 1 and perpendicular to the vertical direction 9, spaced apart from each other and opposite to the vertical direction 9. A clamping arm 13 is attached to the end of each tension arm 12 opposite the transverse arm 10. A contact wire 14 is held between these clamping arms 12 at clamping points 19.

[0034] The in Fig. The conductor rail 4 shown is usually composed of a multitude of conductor rail sections arranged in profile 7. Fig. 1. The end faces are seen and are precisely aligned with each other via butt tabs 15. The mutual alignment is achieved by a positive locking mechanism acting in the vertical direction 9 between the butt tabs 15 and the conductor rail sections, which is in Fig. 1 is designed as a tongue-and-groove connection 16. Screws 17 can be screwed into the butt plates 15 to fix the individual conductor rail sections to each other. To clamp the contact wire 14 between the clamping arms 13, routes 18 extending in or against the transverse direction 11 are connected at a connection point between the clamping arms 13 and the tension arms 12, on which a threading carriage (not shown) can move.

[0035] In the present invention, a light metal is used as the material for the contact wire 14. Alternatively, an alloy with the light metal as an alloying component, in particular as the main component with more than 50 wt.% based on the total weight of the alloy, can also be used.

[0036] Light metals are known to be metals with a density of less than 5 g / cm³. 3 , under standard conditions and at a temperature of 20°C. Aluminum is particularly suitable for this application due to its low density of approximately 2.7 g / cm³. 3 with an electrical conductivity of 37 * 10 6 S / m is suitable for the intended application. Further alloying elements can additionally improve advantageous properties of the contact wire, such as its hardness as resistance to mechanical damage.

[0037] The contact wire 14 used according to the invention can preferably consist of aluminum or, more preferably, an aluminum-containing alloy over its entire cross-section. The contact wire 14 has a circular cross-section with two V-shaped grooves 21. The contact wire 14 exhibits mirror symmetry, with both V-shaped grooves 21 being arranged in a first half 24 of the contact wire 14. The contact wire 14 can also have a sequence of marking grooves 20 for material identification.

[0038] The Rockwell hardness (E) at 23°C is preferably 75.0, making the aluminum sufficiently resistant to mechanical wear under typical operating loads. At the same time, the contact wire 14 material conforms optimally to the clamping arms 13, as the clamping arms 13 penetrate deeper into the grooves 21. This results in better sealing of the contact points 22 between the contact wire 14 and the clamping arms 13, with a larger surface area in contact with each other.

[0039] The contact wire 14 can have a sequence of marking grooves 20 for material description.

[0040] In a preferred embodiment of the present invention, the contact wire can have a greased surface.

[0041] A preferred cross-sectional area of ​​the contact wire is more than 135 mm². 2 , preferably between 140-160 mm 2 , especially 150 mm 2 .

[0042] The contact wire consists essentially, i.e., at least 98 wt.%, of aluminum. Furthermore, the contact wire may contain at least 0.18 wt.%, preferably between 0.2 and 0.6 wt.%, of silicon. The contact wire also preferably contains at least 0.4 wt.%, preferably between 0.45 and 0.9 wt.%, of magnesium. Preferably, this is an aluminum-magnesium-silicon alloy with a higher proportion of magnesium than silicon.

[0043] The electrical conductivity of the contact wire is preferably between 2.1 and 3.4 * 10⁻⁶. 7 S / m at a measurement temperature of 23°C.

[0044] The smallest groove spacing 23 is preferably between 6.7 and 6.95 mm. This groove spacing refers to the distance between the two lowest points of the two V-shaped grooves 21.

[0045] The height and width of the contact wire 14 are preferably equal, less a tolerance of 0.1 mm. Under standard conditions, the payload of the contact wire is preferably more than 40,000 N, and particularly preferably 42,000–48,000 N.

[0046] The use of a lightweight metal, due to its lower weight, makes the installation of the contact wire easier when it is unwound from a continuous reel. This results in reduced transport and installation costs for the contact wire 14. Reference sign 1 Direction of travel / Longitudinal direction 2. Route 3 tracks 4 busbar 5 Ceiling 6 Suspension distance 7 Profile 8 Profile axis 9 Altitude 10 cross arm 11 Transverse direction 12 clamping arms 13 Clamping arm 14 Contact wire 15 butt tabs 16 tongue and groove connection 17 screws 18 roads 19 clamping points 20 marking grooves 21 V-shaped grooves 22 contact points 23 smallest groove spacing 24 half

Claims

[1] Conductor rail of an overhead line comprising at least two clamping arms and a contact wire for contacting a pantograph of a rail vehicle, wherein the contact wire is made of aluminium or an aluminium alloy, wherein each clamping arm engages in a groove of the contact wire and thereby clamps it, wherein the clamping arms are made of aluminium or an aluminium alloy. [2] Busbar according to claim 1, characterized by , that the contact wire is designed as a grooved contact wire with two grooves opposite each other on the side of the contact wire, preferably in a V-shaped design. [3] Busbar according to claim 1 or 2, characterized by that the contact wire is made of aluminium or an aluminium alloy. [4] Busbar according to claim 3, characterized bythat the aluminium alloy is designed as an aluminium-magnesium-silicon alloy, preferably with an aluminium content in the alloy of more than 97 wt.%, particularly preferably more than 98 wt.%. [5] Busbar according to claim 4, characterized by , that the alloy contains at least 0.18 wt.%, preferably between 0.2 - 0.6 wt.%, silicon and that the alloy contains at least 0.4 wt.%, preferably between 0.45 - 0.9 wt.%, magnesium, wherein the proportion of magnesium is always higher than the proportion of silicon. [6] busbar according to one of the preceding claims, characterized by , that the contact wire has an electrical conductivity between 2.1-3.4 ∗ 107 S / m at 23°C. [7] busbar according to one of the preceding claims, characterized by that the cross-sectional area of ​​the contact wire is more than 135 mm2, preferably between 140-160 mm2, in particular 150 mm2 + / - 3mm. [8] busbar according to one of the preceding claims, characterized by that the grooves are arranged on the first half of the contact wire. [9] busbar according to one of the preceding claims, characterized by that the clamping arms for clamping the spring wire are made of aluminium or an aluminium alloy, preferably of a material analogous to the contact wire. [10] Use of aluminium or an aluminium alloy for a contact wire of a conductor rail of an overhead line, the conductor rail comprising at least two clamping arms and the contact wire for contacting a pantograph of a rail vehicle, characterized by , that the contact wire is made of aluminium or an aluminium alloy, wherein a clamping arm engages in a groove of the contact wire and thereby holds it clampingly, wherein the clamping arms are made of aluminium or an aluminium alloy.

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