EP1857160A1 - Track bed section for a model railway - Google Patents

Abstract

The track bed section (5) is die casted from a thermoplastic elastomer, such that it is strongly flexible to be adaptable to all tracks (1) with user-defined, different radius of curvature. A homogeneous structure is provided without granular border and without porous border surfaces. Two longitudinal and multiple crosswise running recesses (10,11) are provided in upper side (9) of the track bed section, for inserting ties (3) and rails (2), which has constant width uninfluenced by the bending radius of the track bed section. An independent claim is also included for a method for manufacturing of a track bed section.

Description

On the one hand, the invention is directed to a track bed section for retrofitting a model railway installation by placing it under the sleepers of the tracks, of solid, substantially trapezoidal cross section, with a flat underside and two continuous longitudinal edges, followed by a closed top, which follows in their visible areas Type of ballast bed is designed while their railroad tracks supporting the surface areas have a smoother and non-porous nature, so that they absorb the compressive force from the sleepers of the track extensively, and with at least two flat end faces without projections and depressions; on the other hand, a method for producing such a track bed section; and finally to its use.

As a result of its trapezoidal cross-section, its continuous longitudinal edges and the closed upper side, such a track bed section is exactly replicated in its appearance to a real ballast bed; the flat faces allow the track bed section to be shortened with little effort if necessary.

An approximately generic track bed section is the German utility model 79 19 950 U1 refer to. This concerns a shaped block for a track bed for garden railroad tracks, which is suitable as a substructure for model railways of all gauges and track pieces and consists of washed concrete. Although this material has the advantage that the sleepers of the tracks rest on a very strong material, so that, for example. Coming from a passing train compressive force can be picked up and removed without noticeable deformation and therefore without damaging the joints between the tracks; on the other hand, due to the hard material, such a track bed section is not able to be adapted to rails having different radii of curvature. It is therefore necessary to provide for track sections with different curvatures each exactly matched and therefore different track bed sections. In addition, washed-out concrete is a very heavy material used during transport and when laying requires an immense effort. With small gauges there is also the risk that relatively thin track bed sections can break.

From these disadvantages of the described prior art, the problem initiating the invention results in the further development of a generic track bed section such that it can be used for each track irrespective of its radius of curvature. Here, the track bed section should support the sleepers of the track and dampen the Schallübetragung largely. The thus inserted between the ground and track sleepers material should also support the tracks firmly so that they do not move against each other and the decisive for the power line contact resistance at the joints between the tracks is not affected. The material should also be insensitive to temporary, thermal overheating, eg. As a result of a soldering iron.

The solution to this problem is achieved in a generic track bed section in that it is injection-molded from a thermoplastic elastomer, so that it is so flexible that it can be adapted to all common tracks with any different radius of curvature that he also has a homogeneous structure without Having grain boundaries and no pore interfaces and in the top at least two longitudinal and many transverse recesses for inserting sleepers and rails, which have a constant, almost uninfluenced by the bending radius of the track bed section width;

The special material used makes it possible to offer only one (originally) straight stretched track bed section type, which can then be bent on demand about a vertical axis, until it is adapted to each track, regardless of its radius of curvature. Therefore, the production cost is significantly reduced. By the flexibility is effected by the material itself and not by, for example, transverse incisions, depressions, bending lines od. Like., The width of a threshold recess during bending is hardly affected, so that even curved tracks without jamming in the space provided Wells can be inserted. Since flexible material is generally a lower one Density as a hard material such as, for example, washed concrete, no special effort is required for laying. In addition, a hard material can break much more easily under shock loads than a flexible material. A thermoplastic elastomer, in contrast to rubber (both natural rubber and synthetic rubber), is an age resistant material whose elasticity properties are very stable and are not compromised even on temporary heating above its melting point and subsequent cooling. Further, the manufacturing step of vulcanization is not required; the thermoplastic elastomer is physically crosslinked and not chemically, generally without the addition of sulfur.

The material properties of increased flexibility are usually associated with a likewise increased elasticity, which in turn strongly dampens the noise of moving trains or the propagation of sound waves along the tracks and or the transmission of these waves on a substrate. This effect is optimal if a track bed section made of a material with a modulus of elasticity E is close to that of soft rubber, ie E ≦ 10 kN / mm ² , preferably E ≦ 5 kN / mm ² , in particular E ≦ 2 kN / mm ² , or even E ≤ 1 kN / mm ² . On the other hand, it is preferable not to use too soft material, so that the track bed section under pressure load little or almost no yield, ie, for example, E ≥ 0.1 kN / mm ² , preferably E ≥ 0.2 kN / mm ² , in particular E ≥ 0.5 kN / mm ² .

The invention recommends to produce a track bed section of a homogeneous material. A homogeneous material is largely free of grain and / or pore interfaces where a notch effect could result. Therefore, such a material on the one hand better able to perform strong bends, as for example. Styrofoam or polystyrene, where already form with small changes in shape cracks, which eventually lead to the destruction of the material. On the other hand, a pore- and bubble-free material has a high mechanical stability, especially against compressive forces.

A track bed section should be made of a crosslinked material, especially a polymer. Especially through intensive networking, the formation of cracks is counteracted to a particular degree.

The desired material properties bring especially organic materials, so that they are particularly suitable as a trackbed material. Two-phase systems, consisting of a soft and a hard phase, have proven particularly useful. In this case, the invention gives the block polymers, wherein the hard and soft phase in the same molecule in the form of Makromolekülsegmenten are involved [TPE-S = styrene copolymers; TPE-A = polyester block amides; TPE-E = copolyester], over the elastomer blends, where hard and soft phases are to be found as a heterogeneous phase distribution of elastomers and thermoplastics [TPE-V = (partially) cross-linked olefins; TPE-O = uncrosslinked olefins].

From this, the invention preferably selects thermoplastic elastomers based on styrene, wherein the styrene blocks contribute to the strength of the material at the ends of the macromolecules, while in the middle part of the macromolecule an ethylene-butylene block, an ethylene-propylene block, a butadiene block or an ethylene-butylene / butadiene block, especially in the form of a hydrogenated block.

The resulting styrenic block copolymer, especially styrene-ethylene / butylene-styrene (SEBS) or styrene-ethylene / propylene-styrene (SEPS), has the optimum properties for this invention. It is a relatively inexpensive material with good elasticity, but is not too soft. The acid and base resistance are also good.

The melting point of the material should be above 120 ° C, preferably at 150 ° C or above, especially at 180 ° C or above, so that temperatures up to 100 ° C are easily tolerated by the material. This can happen even in the - in model trains frequent - handling the soldering iron little, in contrast to, for example, polystyrene od. Like.

A track bed section should be made of an electrically non-conductive material so that no short circuit can occur between current-carrying conductors and / or tracks. It is therefore advisable to use a material with a specific electrical resistance of at least about 10 ⁶ Ωm or above.

By a track bed section consists of a material which can be cut with a knife or a pair of scissors, so that a necessary shortening of the length of a track bed can be effected with the simplest means. This property results on the one hand from the flexibility of the material, but on the other hand also from the renunciation of reinforcing fibers, for example. Glass fibers od. Like.

When the injection molding compound is mixed with dye, pigments or the like, cut surfaces always have the same color as the original surface. For this reason, cut surfaces are not noticeable even if they are not obscured by an adjacent track bed section. According to an original ballast bed is recommended as gray, anthracite or black.

The underside can be closed, resulting in a particularly large contact surface. On the other hand, it is also possible to incorporate into the underside exclusively in the longitudinal direction extending profiling, for example. One or more longitudinal grooves to save material, which can lead to a not inconsiderable cost reduction, especially in large track widths.

If the end-side end faces of the track bed section run parallel to one another, adjacent track bed sections can be pushed together without a gap, giving the impression of a continuous track bed. It is also possible to shorten a track bed section with a straight cut, which can be applied parallel to the previous one.

A symmetrical and therefore particularly simple arrangement is obtained in that the end-side end faces of the track bed section are traversed vertically by the longitudinal axis of the track bed section.

It is within the scope of the invention that the length of a track bed section, i.e., the distance between its two end faces, is greater than the length of the longest track section. In this case, each time the butt joint shifts between two track bed sections opposite the butt joints between adjacent track sections. The result is that in the context of a several meters long track at most once a butt joint between two track bed sections coincides with a butt joint between two track sections. This ensures a particularly smooth or kink-free course of a rail track, because at the butt joints between two track sections, there almost always continuous track bed supports aligned alignment of these tracks. Conversely, a continuous rail track at the butt joints of the track bed sections helps to optimally align them.

In accordance with this inventive idea, the invention provides that the length of the track bed section, i.e. the distance between its two end faces, is greater than the length of the longest track section by a multiple of the mean distance between two corresponding edges of adjacent sleepers. In such a case, the transverse depressions joined together track bed sections for receiving the thresholds always constant distances even over a Soßfuge.

The longitudinal and transverse recesses should have a common, flat bottom surface. On the one hand, this simplifies the shape of an injection-molded part and thus also its tool. On the other hand, it is then also possible to use track sections whose sleepers are connected to one another below the rails to form a ladder-like framework. Finally, the rails are maximally cut free, so that the wheel rims of rail vehicles can nowhere abut.

In fact, the depth of the transverse recesses could correspond approximately to the height of a threshold. However, by making the depth of the longitudinal and transverse recesses smaller than the height of a threshold, the latter slightly overlie the surface of the ballast bed, as does reality. As a preferred measure, the invention recommends that the depth of longitudinal and transverse recesses is about half as large as the height of a threshold.

The base of a transverse recess should correspond approximately to the base of a threshold, so that the latter can be used without jamming in it, but on the other hand also experiences a leading orientation or grants the trackbed.

In order for rail vehicles to be able to roll along the rails above a track bed according to the invention without hindrance, it is advantageous for the width of the upper-side, longitudinally extending recesses to be greater than the width of a rail. Even wheels with a pronounced wheel flange then find enough space inside the longitudinal recesses of the track bed.

Since the flanges are usually located on the inside of the wheels of a wheelset, it is recommended to choose the distance between the upper side, longitudinal recesses smaller than the track width of the track. For example. the respective outer rail flanks can ensure the relative alignment between a pair of rails on the one hand and the relevant track bed, while the inner rail flanks thereby obtain a maximum clearance.

In order to make the track bed according to the invention as realistic as possible, the upper side between and next to the upper-side recesses of a ballast surface should be correspondingly structured, that is, actively generated by a corresponding design of an injection mold.

A track bed section according to the invention can even be used for the region of a switch if it is divided in the region of the mutually diverging rail sections in the longitudinal direction, so that one half of the outside of the straight through rail section can be placed and the other half of the outside of the branching track. The area of the switch tongue is usually already provided with a ballast-like surface. To facilitate a smooth longitudinal section, a track bed section can be about have centrally extending (longitudinal) marking, along the example. A carpet knife or a razor blade can be guided along.

Furthermore, it is the teaching of the invention that the mark is arranged on the underside of the track bed body so that it does not stand out in an undivided track bed section. In addition, the flat bottom of a track bed section is much better suited for the preparation of a longitudinal section than its ballast-like structured top.

On the other hand, it is also possible to provide for the region of a railroad crossing or crossing a specially shaped track bed section, with a course of branching or crossing structure. Such a track bed section naturally has more than two faces, namely at points three, at junctions four; However, these are always flat, so that a normal track bed section can be added seamlessly. In addition, in the case of the special track bed sections, there are four longitudinal recesses instead of two on the upper side. In addition, in track bed sections for switches in the area below the switch blade can provide a recess or interruption of the structured surface, so that the switch blade can move without obstruction. Finally, there are model railway turnouts with an electromagnetic drive in a laterally mounted box; in that case, a special track bed section may engage under this attached box, as if it were part of the rails.

A suitable method for producing a track bed section of an elastic material according to the invention for retrofitting a model railway installation is characterized in that a thermoplastic elastomer is processed in an injection mold to a track bed molding with a homogeneous structure without grain and / or pore interfaces, wherein in the Top of the track bed section molding two longitudinal and many transverse recesses for inserting sleepers and rails are formed, which have a constant, almost uninfluenced by the bending radius of the track bed section width. The injection molding can be done on so-called. Thermoplastic machines. The cylinder temperature should be at 160 ° C to 220 ° C, with the front cylinder zone as well as the nozzle at 170 ° C to 220 ° C should be warmed up; the rear cylinder zone may be lower by about 10 ° C. As tool temperature, a range of 30 ° C to 60 ° C is recommended. The injection molding compound should have a temperature of 170 ° C to 210 ° C and be injected at a pressure of 60 to 120 MPa. The injection speed can be fast, as reprinting suffices about 1/3 of the injection pressure.

Fig. 1

einen Gleisabschnitt mit einem untergelegten Gleisbettkörper nach der Erfindung in einer perspektivischen Ansicht, teilweise abgebrochen;

Fig. 2

eine Draufsicht auf den Gleisbettkörper aus Fig. 1 in gerade gestrecktem Zustand;

Fig. 3

einen Schnitt durch die Fig. 2 entlang der Linie III - III; sowie

Fig. 4

einen Schnitt durch die Fig. 2 entlang der Linie IV - IV.

Further features, details, advantages and effects on the basis of the invention will become apparent from the following description of a preferred embodiment of the invention and with reference to the accompanying drawings. Hereby shows:

Fig. 1

a track section with an underlying track bed body according to the invention in a perspective view, partially broken away;

Fig. 2

a plan view of the track bed body of Figure 1 in a straight stretched state.

Fig. 3

a section through the Figure 2 along the line III - III; such as

Fig. 4

a section through the Fig. 2 along the line IV - IV.

The track section 1 of FIG. 1 is used in a model railway system, eg. With the scale H0, N od. Like.

Typically, such a track section 1 comprises a pair of rails 2 and a plurality of transverse ties 3, which interconnect the rails 2 at regular intervals. While the rails 2 mostly consist of an electrical conductor, for example metal. The sleepers 3 are usually made of an insulator, for example of a hard, inflexible plastic. Each rail 2 carries at one end a connecting shoe 4, in which the end of the rail 2 of an adjacent track section 1 is inserted.

Such track sections 1 are normally screwed by means of screws on a plate of the model railway system, for example. Through holes provided in some thresholds 3. The load-bearing plate of a model railway system consists mostly of wood, mostly from pressed chipboard. Due to its large surface, such a plate acts similar to the soundboard of a grand piano, namely amplifying sound vibrations. Therefore, the noise of moving trains is perceived by the audience of a model railway layout increased and perceived as very unnatural.

Since such a track sections 1 also a ballast bed is not provided, also gives a visually very unnatural impression. Of course, the mounting plate of the model railway system can be coated with adhesive and then sprinkled with a dark powder to create an at least two-dimensional impression of a ballast bed. If the construction of a model railway system was based on this principle, the owner experiences a nasty surprise if the system is to be dismantled or rebuilt at a later date. By the adhesive of the ballast bed, the track sections 1 are inextricably linked to the mounting plate, and in a defiant attempt to solve the track sections 1 by force, usually break the thresholds 3 of the rails. 2

Not so when using a ballast bed 5 according to the present invention. As can be seen Fig. 1, results with such a track bed 1 a stunningly realistic impression of a ballast bed. In addition, this does not require the use of adhesive. But the sound transmission from the tracks to a mounting plate is significantly attenuated.

A track bed 5 has a flat bottom 6, two continuous longitudinal edges 7, two planar, perpendicular to the bottom 6 and also to the longitudinal edges 7, approximately trapezoidal end faces 8 and a structured top 9th

In Fig. 2 details of the top 9 can be seen. In a gravel-like structured outside two longitudinal and many transverse recesses 10, 11 are incorporated, which intersect and are thus interconnected to a ladder-like structure, but with laterally over the longitudinal beams of such a ladder protruding rungs, wherein the longitudinal beams correspond to the two longitudinal recesses 10 and the sprouts the transverse recesses 11th

The transverse depressions 11 serve to receive the sleepers 3. For this purpose, the length of these depressions 11 is dimensioned according to the length of the sleepers 3, and their width corresponds to the width of the sleepers 3. However, the depth of the transverse depressions 11 is smaller than the height of the thresholds 3, so that they easily over the top 9 of the track bed section 5 survive.

The two longitudinal recesses 10 are used for free cutting of the rails 2, so that even train wheels with an oversized wheel flange can roll along smoothly on the track 1. Therefore, the distance between the two longitudinal recesses 10 is smaller than the distance between the two rails 2, and their width is greater than the width of a rail 2, but also greater than the width of a connection shoe 4. The depth of the longitudinal recesses 10th approximately corresponds to the depth of the transverse recesses 11, so that there is a common, flat bottom surface 12.

The distance 1 between the two end faces 8 corresponds to a multiple of the sum of the width b of a threshold 3 and their spacing d: $$\mathrm{1}\mathrm{=}\mathrm{n}\mathrm{*}\left(\mathrm{b}\mathrm{+}\mathrm{d}\right)\mathrm{.}\mathrm{n}\mathrm{\in }\mathrm{N}\mathrm{,}$$

This ensures that even at the butt joints the distance between the sleepers 3 of adjacent track sections 1 remains constant. Preferably, the multiplication factor n is greater than the number k of the thresholds 3 of the longest track section 1: $$\mathrm{n}\mathrm{>}\mathrm{k}\mathrm{,}$$

It follows that the length 1 of a track bed section 5 is greater than the length L of a track section 1. This is important so that the joints between two Track bed sections 5 and the butt joints between two track sections 1 as possible never coincide.

The track bed section 5 is made of a plastic, preferably of a polymerized material. As a result, it has a high flexibility, so that it can be easily adapted to track sections 1 with a wide range of curvature. He experiences his leadership by the engaging in the recesses 11 sleepers 3, which in turn are aligned by the rails 2.

At the bottom 6 of a track bed section 5, a central, longitudinal notch may be present. This is to serve as a template, so that a track bed section 5 can be divided at least in sections in its longitudinal direction in two halves in the region of a switch. Of this, one half of the outer rail 2 of the straight through track 1 can be placed, the other half, however, the outer rail 2 of the curved branch track 1. The area below the switch blade is usually not visible anyway. The same principle can be applied to intersections, where only the respective outer rails are underlaid with a track bed half according to the invention.

Of course, specially designed track bed sections can be offered for such situations at switches and crossings.

Claims (14)

Track bed section (5) for retrofitting a model railway system by placing it under the sleepers (3) of the tracks (1), of solid, substantially trapezoidal cross section, with a flat underside (6) and two continuous longitudinal edges (7), followed by a closed top (9), which is partially designed in the manner of a ballast bed, while their thresholds (3) of the track (1) supporting surface areas have a smoother and non-porous nature, so that they the compressive force from the sleepers (3) of the tracks (1 ) record over a large area, and with at least two flat end faces (8) without projections and depressions, characterized in that it a) is injection molded from a thermoplastic elastomer, so that it is so strong flexible to be adapted to all common tracks (1) with any different radius of curvature can; b) has a homogeneous structure without grain boundaries and without pore interfaces; such as c) in the top (9) has at least two longitudinal and many transverse recesses (10,11) for inserting sleepers (3) and rails (2), which has a constant, almost uninfluenced by the bending radius of the track bed section (5) width exhibit. Track bed section according to claim 1, characterized in that it consists of a (physically) cross-linked material, in particular of a polymer plastic based on styrene. Track bed section according to one of claims 1 or 2, characterized in that it consists of a material having a high melting point T _S , for example T _S ≥ 120 ° C, preferably T _S ≥ 150 ° C, in particular T _S ≥ 180 ° C. Track bed section according to one of claims 1 to 3, characterized in that the injection molding compound with dye, pigments od. Like. is mixed, so that cut surfaces have the same color as the original surface. Track bed section according to one of the preceding claims, characterized in that the underside (6) is closed. Track bed section according to one of the preceding claims, characterized in that the underside (6) has an exclusively longitudinally extending profiling. Track bed section according to one of the preceding claims, characterized in that the end-side end faces (8) of the track bed section (5) extend parallel to one another. Track bed section according to one of the preceding claims, characterized in that the longitudinal and transverse recesses (10, 11) have a common, flat bottom surface. Track bed section according to one of the preceding claims, characterized in that the upper side (9) between and next to the upper-side recesses (10,11) is structured according to a ballast surface. Track bed section according to one of the preceding claims, characterized by an approximately centrally extending marking, preferably on the underside (6) of the track bed section (5). Track bed section according to one of the preceding claims for placement under a rail switch or a rail crossing, characterized by a course with a branching or crossing structure. Method for producing a track bed section (5) from an elastic material for retrofitting a model railway installation by placing it under the sleepers (3) of the tracks (1), of solid, essentially Trapezoidal cross-section, with a flat bottom (6) and two continuous longitudinal edges (7), which is followed by a closed top (9), which is partially designed in the manner of a ballast bed while their the sleepers (3) of the tracks (1) supporting Surface areas have a smoother and non-porous nature, so that they absorb the compressive force from the sleepers (3) of the track (1) over a large area, and with at least two flat end faces (8) without projections and depressions, characterized in that a) a thermoplastic elastomer is processed in an injection mold b) to a track bed section molding (5) having a homogeneous structure without grain and / or pore interfaces; c) wherein in the upper side (9) of the track bed section molding (5) at least two longitudinal and many transverse recesses (10,11) for inserting sleepers (3) and rails (2) are formed, which is a constant, of which Bending radius of the track bed section (5) have almost uninfluenced width. Use of a track bed section (5) made of an elastic material for retrofitting a model railway system by placing it under the sleepers (3) of the tracks (1), wherein the track bed section (5) has a solid, substantially trapezoidal cross-section, with a flat underside (6). and two continuous longitudinal edges (7), which is followed by a closed top (9), which is partially designed in the manner of a ballast bed, while their thresholds (3) of the tracks (1) supporting surface areas have a smoother and non-porous nature, so that they absorb the compressive force of the sleepers (3) of the tracks (1) over a large area, and with at least two flat end faces (8) without projections and depressions, characterized in that a) an elastic, molded from a thermoplastic elastomer trackbed section molding (5) is used; b) with a homogeneous structure without grain and / or pore interfaces; c) in its upper side (9) at least two longitudinal and many transverse recesses (10,11) for inserting sleepers (3) and rails (2) are formed, which have a constant, almost uninfluenced by the bending radius of the track bed section (5) width. Use of a track bed section (5) according to claim 13, characterized in that a uniform track bed section-shaped body (5) for all straight tracks (1), for all curved tracks (1) and possibly also for all turnouts and / or intersections is used ,

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