EP2440706A1

EP2440706A1 - Arrangement for heating railroad switches

Info

Publication number: EP2440706A1
Application number: EP10721827A
Authority: EP
Inventors: Jörg MOHRICH; Wolfram Zeise
Original assignee: Balfour Beatty PLC
Current assignee: Balfour Beatty PLC
Priority date: 2009-06-11
Filing date: 2010-06-09
Publication date: 2012-04-18
Also published as: DE102010029854A1; WO2010142720A1

Abstract

The invention relates to an arrangement for heating railroad switches, comprising a shaped element which has a space accommodating a heat source and which can be connected to the switch element of the railroad switch. The aim of the invention is to improve the transfer of energy into the switch. Said aim is achieved by arranging the shaped element on the switch element, namely an outer rail or switch point, below the head of the outer rail or switch point, and designing the shaped element in such a way that the space accommodating the heat source can be connected to the switch element so as to conduct heat across the largest possible contact surface facing the switch element.

Description

Arrangement for heating railroad switches

The invention relates to an arrangement for heating railway turnouts with a mold element having a heat source space receiving a heat source, wherein the mold element is connectable to the switch element of the rail switch.

EP 1 262 597 A2 discloses a point heater of the type mentioned in the introduction, in which the heat input into the stock rail is to be made possible by means of a liquid heating medium, in contrast to conventional electric heaters. For this purpose, it is described how heat energy preferably obtained from geothermal energy is transmitted to rail elements by means of a liquid heat medium in order to heat the rail elements and to keep them free of snow and ice. The described embodiments of the form elements are referred to as plates, sheets, U-rails cross section, etc. and describe the embodiment of a non-descript metallic material. These are connected by gluing or by welding with good thermal conductivity with the rail elements.

In this case, in one embodiment, a shaped element has two heat channels, which lie in the region of the rail head and in the region of the rail foot. The distance between the two channels is either complied with that they are attached directly in these areas, for example, glued, or that between them a spacer is provided, which also allows attachment via the rail bolts.

First, it is disclosed that the arrangement of the heat channels on the inside of the stock rails, so the side facing the respective switch blade occurs. This seems practically impossible, since on the one hand, the mounting options are limited and on the other hand, the space between the switch blade and the stock rail is limited.

On the other hand, heat is introduced into the rail only in the area of the heat channels. The spacer, if it is assumed that this solution in EP 1 262 597 A2, has no or only negligible heat conduction properties. He is also not designed for heat conduction. In order to bring in the required power, which may be a few kW per turn, in this way in the stock rail, it requires a high flow temperature of the liquid heat medium this is in contradiction to the geothermal use, where there is a desire for the lowest possible flow temperature. This heater is intended for the use of geothermal energy. It can be assumed that geothermal plants operate efficiently up to a flow temperature of 4O ⁰ C, ie that up to this temperature the electric energy input is significantly lower than the thermal energy gained. Additional flow temperatures worsen energy efficiency exponentially.

Also, the spacer in the disclosed form only insufficiently achieves a clamping force on the connection of the heat channels to the stock rail, which increase the heat transfer resistance therebetween, which also speaks against the use of a low flow temperature.

Due to the geothermal heat generating device high required flow temperature only low energy efficiency can be achieved. The advantage of Heat energy production from geothermal energy is at least partially lost again due to the high flow temperature required for the energy input. Also, the proportion of heat loss due to heat radiation increases at higher flow temperatures.

Furthermore, in EP000001262597 a welding is proposed to achieve optimum heat transfer from the mold element to the rail element to be heated. All welding processes contribute to a considerable extent heat energy in the rail elements, which sometimes lead to indefinable and therefore intolerable microstructural changes in the rails. Therefore, only certain welding processes with very high quality requirements are permitted for welding on rails.

Apart from that, the attachment of a relatively large-area, positive-fitting element on the rail by means of a welding process only in the edge regions of the formula element is possible. A full-surface welding is not possible because of lack of accessibility of the gap between the molding element and rail. The heat transfer obstructing air gap resulting from the aforementioned reasons can not be avoided by welding in the edge areas.

Alternatively, EP000001262597 proposes the use of a thermally conductive, permanently elastic adhesive for attaching the mold elements to the rail elements to be heated. Thermally conductive adhesives, as well as thermal compounds in general, have the advantage of filling the air gap between the mold and rail element and to ensure a good heat transfer to the rail elements to be heated. The secure attachment of the mold elements The rail makes very high demands on the adhesive bond. According to standard EN 50125-3 "Railway applications - environmental conditions for equipment", rails with rms values for the vertical acceleration of 280 rn / s "are to be expected. Therefore, adhesives with high

Shear strength can be used, which preclude the required in EP000001262597 property for permanent elasticity.

There are still high demands on the shear strength of the adhesive, if for the

Form elements materials are used, which have a different specific thermal expansion coefficient than the material of the rails. Rails are subject to environmental influences (note: not by heating for the purpose of keeping snow and ice free) a temperature clearance of more than 100 K. These rail temperatures are transferred to the mold elements with the corresponding thermal expansions in the mold elements. If the back rails of a switch welded to the rails of the surrounding track as an "endless" strand, finds in the cheek rails despite

Temperature play virtually no thermal expansion. The thermal expansion in the mold elements at usual lengths up to 6 m, depending on the material used, be more than 1 cm. This difference in length places high demands on the elasticity of the adhesive used.

US000005004190 describes how a preferably electrically heated mold element transfers heat energy to the rail elements. This form element is attached to the side of the rail web, fixed with spring clips and pressed against the rail element frictionally. For the purpose of good heat transfer to the rail element, the mold element is on the rail-facing side with a provided elastic sheet, which should adapt optimally to the contour of the rail. An adhesion or welding with the rail is not provided.

For an optimal transition of the heat energy from the mold element to the rail element to be heated, a positive attachment to the rail element is required. Contour differences between the rail and the form element create an air-filled gap which, due to the poor heat-conducting properties of air, hinders the transition of the heat energy.

European rail suppliers have up to 30 different Vignole rail profiles with 46 kg / m to 70 kg / m in the production program. The standard EN 13674-1 "Railway applications - Track - Rail, Part 1: Vignole rails from 46 kg / m" refers to 21 different Vignol rail profiles as normative, plus other rail profiles, eg grooved rails and construction profiles for switch points Likewise, a large variety of form elements for a positive attachment to the rail element .Thus, a certain form element is always matched to a particular rail profile and not universally usable for other rail profiles.

To make matters easier for a positive attachment is that the rail profiles according to standard EN 13674 may have relatively generous rolling tolerances, so that even with optimally adapted to the contour of the rail profile mold elements can not be mounted practically without air gap on the rail to be heated element.

In US000005004190 it is therefore proposed that to provide the form element on the side facing the rail with elastic sheet, which is the actual contour of the Can adapt rail element and avoids the formation of a heat-insulating air gap. The elasticity of this sheet depends on its material and the material thickness. A small material thickness leads to a high elasticity, but hinders the heat distribution within the sheet and the heat transfer to the rail element as a whole. In order for a sheet with a greater material thickness can conform to the contour of the rail element, it requires appropriate contact forces that must be applied by spring plates.

According to standard EN 13674, rail profiles have rolling marks at intervals of not more than 4 m at the rail web, which are up to 25 mm high and project up to 1.3 mm from the rest of the material. These rolling marks must not be removed by material removal, as this results in intolerable microstructural changes in the rail steel. The up to 1.3 mm raised rolling marks can not be positively enclosed by elastic sheets, as described in US000005004190. This results in the area of the rolling signs air pockets, the heat transfer from

Hinder molding element on the rail element. The invention is now based on the object to provide an arrangement for heating railway switches, with which the energy input is improved in the switch to avoid the disadvantages of the solutions described in EP000001262597 and US000005004190.

According to the invention, this object is achieved in that the molding element on the switch element, namely a stock rail, a switch blade or a movable core, below the head of the stock rail, the

Switching tongue or the movable core arranged and designed so that the heat source space on the the greatest possible contact surface facing the switch element is heat-conductively connectable to the switch element. Characterized in that, in contrast to the prior art, the entire outer side of the rail web is available for the heat input, the required energy can be entered into the stock rail with lower temperatures in the heat source space.

In particular, this is a heating of the contact points between fixed elements, such as cheek rails and Gleitstühlen, and movable elements, such as switch blades and moving centerpieces, a switch allows. Due to weather or caused by a changeover of the switch, can get into these contact points snow and ice, which can lead to adhesion of the movable to the fixed elements of the switch and a

Changing the switch prevents. By heat input into the switch elements at a suitable location is now achieved according to ^¬ fiction, that the aforementioned contact points are kept frost-free and so the convertibility of the switch is guaranteed. The heating of the stock rail as a switch element takes place in the area in which the switch blade on the stock rail or the movable core can rest against the wing rail. The heating of the switch tongue or of the movable frog takes place in the region in which the switch tongue or the movable frog piece is mounted on the slide chairs.

In one embodiment of the invention it is provided that the heat source space is formed as a longitudinally extending cavity whose longitudinal axis extends in the longitudinal extension of the switch element. This form is particularly suitable for the introduction of heat sources of any kind, since It does not form any mechanical resistance and also creates easy connection conditions.

A simple possibility of this realization is that the heat source space is formed as a cylindrical cavity. However, it is also possible that the

Cross-section is oval or kidney-shaped. This ensures that the cross-sectional shape follows approximately the outer contour of the stock rail or the switch blade. Thus, in turn, a relatively large cross-section can be realized, whereby the heat source space can be made large volume and the heat transfer surface between the heat source and the mold element for a good heat transfer can be made as large as possible.

As a heating or heat source in the context of the invention, each source is to be understood, which is able to enter heat energy in the switch element. For example, already water, such as well water with a temperature of 12 ⁰ C in the winter already serve as a heat source, since this has a temperature difference to the temperature of the switch elements in frost, which is sufficient for heat input. Also, the water can come from a geothermal source, such as a geothermal probe. From such a geothermal source, the water has a much higher temperature due to the use of geothermal energy. It is also possible to preheat the water or a suitable other liquid heating medium via a heater located outside of the heat source space, such as an electric heater, for example, to introduce an additional heat energy in the heating medium at very strong frosts. Such an electrical (additional) heating can be cheaper under certain circumstances, such as the establishment of a heat pump, by means of of which the heating medium is to be heated.

Furthermore, it is provided in one embodiment that under the contact surface facing away from the outer surface of the mold element, a heat insulation is arranged.

But also a supplement of the insulating effect is possible by an insulating layer is applied to the contact surface facing away from the outer surface of the mold element.

A first possibility of the effective arrangement of the mold element is given by the mold element is arranged on the stock rail.

In order to avoid that the molded element impairs the functionality of the rail switch, something by faulty sets between stock rail and turnout, the mold element is advantageously on an outer side of the stock rail, which of the

Stock rail facing away from the switch blade is arranged.

In no way interferes with the molding element when it is in the tab chamber of the stock rail, that is, in the space which is determined by the rail head, the rail bridge and the rail foot is determined.

In order to maximize heat input and to prevent icing at any point on the stock rail, the heat source room can be positioned over the entire length in the area of the stock rail and over the entire height of the stock rail

Rail web to be connected with this heat-conducting.

In a variant, it is provided that the heat source space (or the heat source spaces) receives (absorb) a liquid or a gaseous medium as a heat source, by being connected to a heating medium for liquid or gaseous medium. Preferably, the heat source spaces are flowed through by the medium by the first heat source space is connected to a flow and the second heat source space with a return of the heat source. This also allows the use of geothermal energy sources. Since it should be worked with the lowest possible flow temperatures in such energy sources in order to achieve high energy efficiency, the invention provides a very good energy input in the

Rail achieves what low flow temperatures of 2O ⁰ C to 4O ⁰ C allowed.

In a further embodiment it is provided that in the mold element, a first such heat source space and transverse to the longitudinal extent of the mold element to be measured distance to the first heat source space, a second such heat source space is arranged. Both heat source rooms absorb heat sources and are connected to each other in a heat-conducting manner. This arrangement of several heat source rooms with multiple heat sources is to facilitate the

Energy input, since thus the heat can be brought in several places.

For better heat distribution and thus also for better heat input, it is expedient if the molded element consists of a good (heat) conductive material, in particular aluminum or copper, wherein the positive connection between the mold element and the switch part is supported by that in the Assembly of the contact element to the switch part, a thermal paste is introduced. This even the smallest heat-insulating cavities can be avoided in between.

In another embodiment it is provided that the Heat source space, an electric heating element, electrically isolated, as a heat source receives. An electric heater has the advantage that here the energy is very easy to feed. As a result of the inventively improved heat transfer, it is possible to significantly reduce the performance of such electric heaters over the prior art. Here, too, can work with very low heater temperature of less than 4O ⁰ C because the thermal coupling is greatly improved. In electrical heaters according to the prior art, however, worked with temperatures of about 13O ⁰ C.

In particular, for easy insertion of prefabricated heating elements, it is favorable that the heat source space is designed, for example, as a groove open to the contact surface, in which the heating element is inserted from the side of the contact surface. Normally, then, the heating element can be positively secured in the groove. To increase the mechanical safety and to improve the heat transfer, however, it is expedient that the open side of the groove is closed by a sealant.

The cross section of the mold element is designed so that the mold element can consist of extruded profile and thus offers a possibility of cost-effective production.

The thermal insulation may be in the form of a heat-insulating hollow chamber.

Such a hollow chamber can be easily realized in the extruded profile. It prevents unwanted heat radiation to the outside, without having to take special insulation measures. The effect is enhanced when the hollow chamber is located between the heat source space and the outer surface. Between the heat source space and the outer surface usually the largest temperature gradient can be found. In this design, the hollow chamber is in the region of the largest temperature gradient and thus unfolds the greatest possible effect.

Due to the good coupling and insulation, the energy requirement also drops significantly, which also leads to significant advantages in electrical heating.

The insulating effect can be further enhanced by the fact that in the direction of the contact surface to the outer surface lying behind each other at least two hollow chambers are arranged. In order to realize a particularly stable profile, a further embodiment of the shaped element according to the invention is characterized in that an upper bead facing the rail head is provided, which is provided with the first heat source space. Furthermore, a pointing to the rail foot lower bead is provided, which is provided with the second heat source space. Between the upper and the lower bead, a heat-conducting connecting web is provided, which realizes a contact surface of the molded element contacting the outer side of the stock rail, and the contact surface has an inverse (complementary) to the shape of the outer side of the stock rail.

Shape up. The heat-conducting function of the connecting web can be realized in that it is particularly broad in dimension and thus the thermal resistance is minimized. This design is a material-saving and easy-to-install form that still takes little mounting space.

The width and thus the heat-conducting function can be realized in particular by the fact that the mold element has a straight or slightly convex curved in cross-section surface by the connecting web has the same width as the beads.

In a mounting variant is provided that the

Connecting web is provided with through holes, which correspond to rail web bores and through which the mold element by means of bolts and nut, which realize the screw, with the stock rail is connected. About rail bridge holes in the stock rail can then be realized with the help of through-holes in a simple, but very reliable way the non-positive connection. In particular, the mold element is not screwed over the entire length. This would lead to thermal expansion differences with strong temperature differences between the mold element and stock rail. Rather, the screw is preferably the longitudinal fixing of the mold element to secure it over the length of the stock rail then with other suitable flexible fasteners.

Such a fastening variant provides, in particular, that the shaped element can be frictionally connected to the stock rail by means of a tensioning element. The tensioning element has a first tensioning part, which can be connected to the rail foot, and a second tensioning part, which comprises a tensioning unit pressing the form element against the rail web.

In particular, the clamping element may be formed as a one-piece spring element made of spring metal.

A second possibility of the effective arrangement of Form element is given by the mold element is arranged at the switch blade. This is achieved in particular that also the contact points of the switch blade are heated to slide chair with and thus can not freeze.

To avoid functional impairments on the rail switch, the mold element is expediently arranged on an outer side of the switch tongue which faces away from the switch rail associated with the switch tongue.

Preferably, the molding element is arranged on the foot of the switch blade, in particular on the upper side of the switch blade root. Such an arrangement also corresponds to the general feature that the mold element is arranged below the rail head of the switch blade, wherein the rail head of the switch blade can be processed in different ways.

For the best possible introduction of heat, the heat source space over the entire length in the region of the switch blade can be connected to this heat-conducting.

Again, a preferred fastening variant is to be seen in that the mold element by means of clamping element frictionally connectable with the Weichenzungenfuß, wherein the clamping element comprises a first clamping part, which is connectable to the Weichenzungenfuß, and a second clamping part, which is a molding element against the upper side of the Weichenzungenfußes having pressing clamping unit comprises.

A simple but technically effective realization is the fact that the clamping element is designed as a one-piece spring element made of spring metal.

The greatest possible reliability and the most effective Energy use (since the use of energy as possible distributed) can be seen in the fact that a first such mold element is arranged on the stock rail and a second such mold element at the switch blade.

In a further embodiment, it is provided that the shaped element is formed from an elastic, non-metallic material.

Preferably, the mold element can be fixed by means of thermally conductive adhesive to the switch element and designed so that the heat source chamber via the maximum possible the switch element facing contact surface is thermally conductive connected to the switch element.

Characterized in that, in contrast to the prior art, the entire outer side of the rail web is available for the heat input, the required energy can be entered into the stock rail with lower temperatures in the heat source space.

Due to the elastic properties, it is possible that the molded elements exactly match the actual contour of the rail. Vibrations and thermal expansions of

Rail can be transferred to the mold elements, as they are self-expandable. The forces required for this are lower than in the solutions according to the prior art. This reduces the requirements for the strength of the adhesive connection.

The elastic mold elements according to the invention are suitable in a design for liquid-based heating of the rail elements using geothermal heat. In another design, electric energy is used for heating.

It is also possible that the molded element of a three-dimensional textile fabric construction, in which between two textile cover layers, a cavity for the passage of the heat medium realizing textile spacer knitted fabrics are woven, the textile cover layers and their end faces are sealed by thin, elastic and vulcanized into the fabric rubbery films.

The distance between the textile cover layers depends on the desired flow rates. The flow takes place in the longitudinal direction. The connections for supply and return are realized via vulcanised nozzles.

The extensibility of the textile fabric construction ensures the necessary elasticity, so that the molded element can adapt to the contour of the rail elements to be heated. The air gap free wrapping of raised rolling marks in

Connection with thermally conductive adhesive is possible. So that the three-dimensional textile fabric construction can adapt to a thickness of several millimeters of the concave contour of the rail in the transition region from the rail web to the rail head or foot, no Abstandgewirk between the cover layer is provided at these locations. In this way, so to speak, a "buckling" of the formula element is possible without the flow through the heat transfer medium is hindered. The optimum heat transfer from the heat medium to the rail is ensured by a very thin rubber-like film for sealing the textile cover layer. Thermal expansion and vibration of the rail by crossing trains are easily absorbed by the given elasticity of the elastic, textile form elements.

In the design of the elastic mold elements with use of electrical energy for heating the rail elements are the advantages of elastic, textile molded elements described above, the energetic benefits of using the largest possible area on the rail, -Steg and foot for heat transfer and the advantages associated with the control and regulation of electrical energy.

For electrical heating, it is provided that the shaped element consists of a two-dimensional, textile fabric construction in whose yarns different conductive yarns are interwoven, which alternate with non-conductive yarns, whereby a parallel connection of the filaments woven in the transverse direction is achieved in the longitudinal direction.

The number and conductivity of the yarns determine the electrical performance of the textile fabric construction. By using highly conductive yarns, their threads in

Longitudinally interwoven with the filaments arranged in the transverse direction, the contacting takes place.

The elastic form elements for electrical heating act as purely ohmic resistance and can thus be operated with DC or AC voltage. Operation with safety extra-low voltage or voltages up to 230 V is possible. For electrical insulation and protection, the elastic, textile fabric construction is vulcanised into a rubber-like film. The layer thicknesses are determined by the electrical voltage level at which the mold elements are operated and the test voltages derived therefrom.

The extensibility of the textile fabric construction ensures the necessary elasticity even in the described design, so that the molded element of the contour of the heated

Can adjust rail elements. The air gap-free cladding raised rolling marks in conjunction with thermally conductive adhesive is possible. Due to the small thickness of the two-dimensional, elastic fabric construction, the molding element can adapt to the rail head or foot in the transition region from the rail web to the rail head or foot without special constructive measures for the concave contour of the rail. The optimum heat transfer from the filament to the rail is ensured by a very thin rubber-like foil, which serves only for electrical insulation. Thermal expansion and vibration of the rail by crossing trains are easily absorbed by the given elasticity of the elastic, textile form elements.

For electrical heating, an electrically heatable mold element can also be formed by the fact that the mold element consists of a foil, the metallic one

Conductor tracks or heating wires, wherein the film with the metallic conductor tracks or the heating wires are embedded and insulated in two silicone mats.

The contour of the conductor tracks can be produced by an etching process. Instead of the film as a heat conductor and individual heating wires can be used. The heating foils or the heating wires are embedded and sealed in two silicone mats. The mechanical and electrical protection is achieved by the silicone mats. Due to the elasticity of the silicone mats, the mold element can adapt to the rail head or foot without special constructional measures of the concave contour of the rail in the transition region from rail web.

The invention will be explained in more detail using an exemplary embodiment. In the accompanying drawings shows 1 is a frontal front view of a fiction, ^¬ contemporary form element,

2 is a perspective view of a molded element according to the invention,

3 shows a cross section through a switch in the region of a stock rail of an arrangement according to the invention for heating railroad switches,

4 shows a cross section through a stock rail with a molding element according to the invention with two heat source spaces,

5 shows a cross section through a stock rail with a molding element according to the invention with two heat source spaces and an additional insulating layer,

6 shows a cross section through a stock rail with a form element according to the invention with an electrical

Tubular heaters in a heat source room,

7 shows a cross section through a switch tongue with a molding element according to the invention with two heat source spaces,

8 shows a cross section through a switch tongue with a molding element according to the invention with an electric pipe heater in a heat source space,

9 shows a cross section through a stock rail with a molding element according to the invention with two heat source spaces with a one-piece spring holder,

10 shows a cross section through a stock rail with a molding element according to the invention with two heat source spaces with a clamping device, 11 shows a cross section through a stock rail with a form element according to the invention from a three-dimensional textile fabric construction and

12 shows a cross section through a stock rail with a form element according to the invention from a two-dimensional textile fabric construction.

An essential component of an arrangement according to the invention for heating rail switches is a molded element 1, as shown in various forms in FIGS. 1 and 10. As shown in Fig. 1 to Fig. 6, Fig. 9 and Fig. 10 Darge ^¬, this molding element 1 is intended for mounting on the outer side 2 ^¬ a back rail 3. This outer side 2 represents the side of the stock rail 3 facing away from a switch tongue 5. Here the shaped element is arranged in the tab chamber 4.

The mold element 1 has a through hole 6, which correspond to through holes in the stock rail 3 and through which a bolt 7 can be inserted therethrough, as shown in Fig. 3, which can then be bolted to a nut 8. Thus, the mold element 1 is fixed in the longitudinal direction of the stock rail 3 and is pressed at this point to the surface of the rail web 9 of the stock rail 3.

In order to allow the best possible thermal contact between the mold element 1 and the stock rail 3, on the one hand, a high adhesion is required, which is applied at this point by the bolt 7 and the nut 8. Over the length of the mold element 1, however, it is not possible to screw this, as this would lead to thermal stresses. Here are other mounting options are provided, which are shown in Fig. 9 and Fig. 10 and will be described in more detail below.

In addition to the traction a good closure is erforder ^¬ Lich. This positive connection is achieved in that the contact surface 10 of the molded element facing the stock rail 3 has an inverse (complementary) shape to the shape of the outside 2.

The mold element 1 is provided as that part of the arrangement for heating railroad switches, which introduces heat into the stock rail 3. For this purpose, 1 heat sources are provided within the mold element. The mold element itself is designed so that the heat of the heat sources is conducted over the entire contact surface 10 to the stock rail 3.

In the example according to FIGS. 1 to 3, the heat sources are designed in that an upper bead 12 facing the rail head 11 is provided, which is provided with a first heat ^source space. Furthermore, a pointing to the rail 14 lower bead 15 is provided, which is provided with a second heat source chamber 16. Both heat source spaces 13 and 16 can accommodate heat sources that can be designed in many different ways. Thus, it is possible to pass through the heat source chambers, a liquid or a gaseous medium. It is also possible to introduce electric heating elements into these heat source chambers 13 and 16 in an electrically insulated manner.

Between the upper 12 and the lower bead 15, a heat-conducting connecting web 17 is provided. The heat-conducting properties of this connecting web 17 are realized on the one hand by the choice of material. The connecting bridge consists, like the entire formula element 1, of a good

(heat) conductive material, such as aluminum or copper. On the other hand, this connecting web 17 has a thickness 18 which provides heat conduction from the heat ^¬ source chambers 13 and 16 such that a heat input ^{¬ takes place} in the rail web 9 of the stock rail 3 over the entire surface over the contact surface 10. When using copper or aluminum, a thickness of preferably 7 mm to 26 mm, preferably 10 mm, is recommended here. This thickness 18 also causes a high mechanical strength, so that the clamping forces can be completely transferred from the mold element 1 to the stock rail 3.

Can be supported the thermal conductivity at the transition from the contact surface 10 to the outside 2, if in between the assembly of the contact element 1 to the stock rail 3, a thermal paste is introduced. This even the smallest heat-insulating cavities can be avoided in between.

An even more pronounced expression of the connecting web 17 experiences this in the embodiments, as shown in Fig. 4 to Fig. 10. Here, the mold element 1 is relatively solid, so that a best possible entry of the heat energy is made possible.

In the embodiment of Fig. 4, the mold element 1 is made of extruded profile, as can be done in the other embodiments. The first heat source space 13 below the rail head 11 and the second heat source space 16 above the rail foot 14 are likewise arranged, and both are connected to one another by the connecting ^web 17. For the purpose of reducing the heat loss via the outer surface 19 remote from the contact surface 10, two heat-insulating hollow chambers 20 are provided below the outer surface 19 of the molded element 1 between the respective heat source space 13 or 16 and the outer surface 19. orders.

The insulating effect can be enhanced if a further insulating layer 21, as shown in Fig. 5, is applied to the outer surface 19. The design of this insulating layer 21 also offers the advantage that it is to make a smooth outer surface.

As shown in Fig. 8, two hollow chambers 20 are arranged in the direction of the contact surface 10 to the outer surface 19 in succession, whereby further the insulating effect is increased.

In the embodiment of FIG. 6 in the heat source chamber 16 an electrical heating element is inserted positively in the form of a ^¬ Heating element body 22. Due to the design of the mold element, in particular by the width of the connecting web 17, a good heat distribution to the entire contact surface 10 is made possible. For introducing the heating element 22, it is provided that the heat source chamber 16 is designed as a groove 23 which is open towards the contact surface 10 and into which the heating element is inserted from the side of the contact surface.

In this case, it is possible to additionally cast the heating element 22 in the groove 23 and also to close the open side of the groove 23 by a sealing means.

In Fig. 7 and Fig. 8 it is shown that the mold element 1 is arranged on the switch blade 5, on the upper ^¬ side 24 of a foot 25 on the outer side 26 of the switch tongue ^¬ tongue 5, the switch blade rail 5 associated with the switch blade 3 is turned away. This is achieved, inter alia, that a located under the foot 25, not shown contact surface for sliding chair with heated becomes .

Conveniently, a respective form element 1 is arranged both on the stock rail 3 and on the switch blade 5 in the manner shown.

In Fig. 9 and Fig. 10 it is shown that the mold element (1) by means of a clamping element 27 with the stock rail 3 is non-positively connected. A similar fastening ^¬ possibility is possible for a mold element 1 on the foot 25 of the switch blade 5, even if this is not shown here.

The tensioning element 27 has a first tensioning part 28, which is connected to the rail foot 14, and a second tensioning part 29 with a tensioning unit 30 pressing the form element 1 against the rail web 9. By means of a clamping screw 31 which is screwed into a threaded bore 32 lying perpendicular to the rail web 9 and which presses on a pressure piece 33, the mold element can be fastened to the rail web. For receiving the pressure piece 33, the outer surface 19 of the mold element 1 has a recess 35, so that the first clamping part 28 shows a positive connection to the mold element 1.

The first clamping member 28 has a first collet 35 which engages one side of the rail foot 14, and a second collet 36 for the other side of the rail foot 14, both of which clamp the rail foot by a pull screw 37. The connection 38 between the first 28 and the second clamping part 29 is elastic, so that the mold element 1 is pressed by an elastic frictional connection against the rail web 9.

The embodiment according to FIG. 10 provides a tensioning element 27, whose first clamping part 28 and second clamping part 29 are integrally connected to each other. The clamping element 27 is designed as a spring element made of spring metal. Here, the second clamping member 29 engages under the rail, and the first clamping member 28 resiliently presses the mold member 1 against the rail web.

The heat source chambers 13 and 16 in Fig. 4, Fig. 5, Fig. 7, Fig. 9 and Fig. 10 are intended to receive a liquid or a gaseous medium as a heat source by each of the heat source space, 13 or 16, with a flow and the other heat source space, 16 or 13, is connected to a return of a heating source, not shown, or better hot water heater.

The power can be 10 kW and more at a switch with conventional electric heating to the

Demands of some rail infrastructure operators, according to which - 2O ⁰ C outside temperature must be kept by heating the rail temperature to +3 ⁰ C. Due to the design of the mold element 1 and its mounting on the stock rail 3, at the switch blade 5 or in the preferred

Trap on both switch elements 3 and 5, it is possible to bring this high performance with a low temperature difference between the heat sources and the rail switch. This makes it possible in particular to work, for example, with low flow temperatures in liquid or gaseous media. Among other things, this also allows the use of geothermal heat generation. It also makes it possible to minimize heat loss due to heat radiation.

As shown in Fig. 11, the molded element 1 consists of a three-dimensional textile fabric construction 39. This has two textile cover layers 40. Between these two textile cover layers 40, a cavity 41 is provided for the passage of the heat medium. This is realized in that between the textile cover layers 40, a textile spacer fabric 42 is woven. The textile cover layers 40 and their end faces are sealed by thin, elastic and vulcanized into the fabric rubbery films 43. The cavity 41 serves as a heat source space in the manner described above. That is, the mold member 1 is connected at both ends of its longitudinal extent with a heating source and the heating medium flowing through the cavities 41 heats this and thus the switch element 3 or 5.

As shown in FIG. 12, the mold element 1 consists of a two-dimensional textile fabric construction 44, in whose yarns conductive yarns 45 are interwoven, alternating with nonconductive yarns 46. Characterized a parallel connection of the filaments woven in the transverse direction in the form of the conductive yarns 45 is achieved in the longitudinal direction. The mold element 1 is connected at both ends of its longitudinal extent with a voltage source and the current flowing through it heats this and thus the switch element 3 or 5.

In both cases of FIGS. 11 and 12, the molded element 1 is connected to the switch element by means of a thermally conductive flexible adhesive 47 - here represented for example as a stock rail 3 - with the outer side 2. Arrangement for heating railroad switches

LIST OF REFERENCE NUMBERS

1 mold element

2 outside of the stock rail

3 stock rail

4 tab chamber

5 switch tongue

6 through hole

7 bolts

8 mother

9 rail bridge

10 contact area

11 rail head

12 upper bead

13 first heat source room

14 rail foot

15 lower bead

16 second heat source room

17 connecting bridge

18 thickness of the connecting web

19 outer surface 20 hollow chamber

21 insulating layer

22 heating element

23 groove

24 top 25 feet of the switch tongue

26 outside of the switch tongue

27 clamping element

28 first clamping part 29 second clamping part

30 clamping unit

31 clamping screw

32 threaded hole 33 thrust piece

34 deepening

35 first collet

36 second collet

37 Tension screw 38 connection

39 three-dimensional textile fabric construction

40 textile cover layer

41 cavity

42 spacer fabric 43 rubber-like film

44 two-dimensional textile fabric construction

45 conductive yarn

46 non-conductive yarn

47 adhesive

Claims

Arrangement for heating railway turnoutspatents claims

1. Arrangement for heating railway turnouts with a mold element having a heat source space which receives a heat source, wherein the mold element is connectable to a switch element of the rail switch, d a c h e c e n e c e s that the

Forming element (1) on the switch element, namely stock rail (3), switch blade (5) or movable core, below the head (11) of the stock rail (3) or the switch blade (5) is arranged and designed so that the heat source space (13 16) via the largest possible the switch element (3; 5) facing the contact surface (10) thermally conductively connected to the switch element (3 or 5) is connectable.

2. Arrangement according to claim 1, characterized in that the heat source space (13; 16) is formed as an elongated cavity whose longitudinal axis extends in the longitudinal extent of the switch element (3; 5).

3. Arrangement according to one of claims 1 to 2, characterized in that under the contact surface (10) facing away from the outer surface (19) of the molded element, a heat insulation are arranged.

4. Arrangement according to one of claims 1 to 3, characterized in that on the contact surface (10) facing away from the outer surface (19), an insulating layer (21) is applied.

5. The arrangement according to claim 1, wherein the heat source space (13; 16) receives a liquid or a gaseous medium as a heat source by being connected to a heating source for liquid or gaseous medium.

6. Arrangement according to one of claims 1 to 5, characterized in that the shaped element (1) consists of a good thermal conductivity material, in particular of a metallic material such as aluminum or copper, and positive and non-positive with the switch element (3; ) connected is.

7. Arrangement according to claim 1, wherein the heat source space (13, 16) receives an electrical heating element (22), correspondingly electrically isolated, as the heat source.

8. Arrangement according to claim 7, characterized in that the heat source space (13; 16) is designed as a groove (23) which is open towards the contact surface (10) and into which the heating element (10) from the side of the contact surface (10) 22) is inserted.

9. Arrangement according to claim 8, characterized in that the open side of the groove (23) is closed by a sealing means.

10. Arrangement according to one of claims 1 to 9, characterized marked egg z egg that the mold element (1) consists of extruded profile.

11. Arrangement according to one of claims 1 to 10, characterized in that a to the rail head (11) facing upper bead (12) is provided, which is provided with the first heat source space (13) that a to the rail foot (14) facing lower bead (15) is provided, which is provided with the second heat source space (16) that between the upper (12) and the lower bead (15) a thermally conductive connecting web (17) is provided which realizes a the outer side (2) of the stock rail (3) contacting the contact surface (10) of the mold element (1) that the contact surface (10) to the shape of the Outside (2) of the stock rail (3) inverse (complementary) shape.

12. Arrangement according to one of claims 1 to 5, d a d u r c h e c e n e c i n e s in that the molded element is formed of an elastic, non-metallic material.

13. Arrangement according to claim 12, characterized in that the shaped element (1) by means of thermally conductive adhesive to the switch element (3; 5) attached and designed so that the heat source space (13; 16) over the largest possible the switch element (3; 5) facing contact surface thermally conductive with the switch element (3, 5) is connectable.

14. Arrangement according to claim 12 or 13, characterized in that the shaped element (1) consists of a three-dimensional textile fabric construction (39) in which between two textile cover layers (40) has a cavity (41) for the passage of the heat medium realizing textile spacer knitted fabric (40). 42) are woven, wherein the textile cover layers (40) and their end faces are sealed by thin, elastic and vulcanized into the fabric rubbery films (43).

An assembly according to claim 12 or 13, characterized in that the forming element (1) consists of a two-dimensional textile fabric construction (44) in whose yarns conductive yarns (45) are interwoven, alternating with nonconductive yarns (46), whereby a parallel connection of the filaments woven in the transverse direction is achieved in the longitudinal direction.

16. Arrangement according to claim 12 or 13, characterized in that the molded element (1) consists of a foil, the metallic conductor tracks or

Has heating wires, wherein the film with the metallic conductor tracks or the heating wires are embedded and insulated in two silicone mats.