UNDER SLEEPER PAD

An under sleeper pad (1) for securing to an outer surface (3) facing a ballast bed (2), in particular an underside (4), of a concrete railroad tie (5). The under sleeper pad (1) has an elastic layer (6) and a connecting layer (7) for connecting the under sleeper pad (1) to the railroad tie (5). The connecting layer (7) has a plurality of elevations (8) for embedding in the concrete of the railroad tie (1), and, in a plan view of the under sleeper pad (1), at least some, preferably all, of the elevations (8) have the shape of a diamond, and the diamond has a greater longitudinal extent (14) than transverse extent (13).

Skip to: Description  ·  Claims  · Patent History  ·  Patent History
Description
CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from Austrian Patent Application No. A9/2025, filed January 13, 2025, which is incorporated herein by reference as if fully set forth.

TECHNICAL FIELD

The present invention relates to an under sleeper pad for connection to an outer surface facing a ballast bed, in particular an underside, of a concrete railroad tie, wherein the under sleeper pad has an elastic layer and a connecting layer for connecting the under sleeper pad to the railroad tie, wherein the connecting layer has a plurality of elevations for embedding in the concrete of the railroad tie.

BACKGROUND

WO 2008/122065 A1 shows an under sleeper pad with different surface structures of the connecting layer.

SUMMARY

The object of the present invention is to provide an under sleeper pad of the type mentioned above, which enables particularly good connection of the under sleeper pad to a concrete railroad tie.

To achieve this object, it is envisaged that, in a plan view of the under sleeper pad, at least some, preferably all, of the elevations have the shape of a diamond, wherein the diamond has a greater longitudinal extent than transverse extent.

Surprisingly, it was initially found that the connection of an under sleeper pad to a concrete railroad tie is particularly strong and durable in the presence of such diamond-shaped elevations. More detailed investigations then showed that the diamond shape of the elevations causes the elevations to become particularly firmly wedged

between the concrete of the railroad tie during the curing of the concrete and the associated shrinkage.

For the sake of completeness, it should be noted that the under sleeper pads according to the invention can of course also be connected to railroad ties that are not made of concrete or do not contain concrete, as long as these railroad ties consist of a material that is sufficiently flowable in its uncured state or at least have a layer of such a material. Ultimately, the only requirement is that the elevations of the connecting layer can be pressed or vibrated into the concrete or other flowable material of the railroad tie before the concrete or other flowable material cures. Once cured, this results in a correspondingly firm connection between the under sleeper pad and the railroad tie. However, since railroad ties are generally made of concrete nowadays, this is the variant that is primarily discussed here, without excluding the connection of under sleeper pads according to the invention with railroad ties made of other materials that are flowable before curing.

In case of doubt, the above-mentioned plan view of the respective elevation is taken in the direction of a normal to the surface of the elevation facing away from the elastic layer. In this respect, the invention could alternatively also be described as having the surface facing away from the elastic layer of at least some, preferably all, of the elevations having the shape of a diamond.

Depending on the required adhesive strength of the connecting layer to the railroad tie or to adapt to different strength classes of the concrete or stiffnesses of the concrete during the concreting of the railroad tie, the under sleeper pad may, in a plan view, additionally comprise differently shaped elevations in addition to the diamond-shaped elevations according to the invention. However, it is particularly preferred that all elevations in the aforementioned plan view have a diamond shape, preferably even the same diamond shape.

An outwardly open porosity in the connecting layer can serve to improve the adhesion of the under sleeper pad to the railroad tie, as this increases the surface area of the connecting layer.

It is therefore preferable that the connecting layer and/or the elastic layer comprise a porous material.

It is particularly preferred that the elevations and/or the areas of the connecting layer arranged between the elevations have a porosity that is open to the outside.

The areas arranged between the elevations are understood to be the flat or deeper areas that lie in the connecting layer between the individual elevations.

It may be that the outwardly open porosity enables a targeted exchange of air, moisture, and/or other substances.

It is preferable that the connecting layer has 5 to 500 pores per mm2, preferably 20 to 350 pores per mm2, and particularly preferably 35 to 250 pores per mm2. This applies in particular to the outward-facing surface of the connecting layer. Specific optimizations can be made here depending on the application and desired functionality.

The pore density describes the number of pores per unit area and has a significant influence on the properties of the layer, including adhesion to concrete, permeability, elasticity, and/or mechanical stability.

It is important to note that the pore density mentioned is to be understood as an average value and that slight local deviations may occur in practice.

These deviations may arise from the manufacturing methods, the material properties, and/or the specific requirements of the application.

For example, in certain areas of the connecting layer, the pores may be slightly denser or less densely distributed to allow for local adaptation of the properties.

For example, the edge areas of an under sleeper pad may have a lower pore density to ensure greater stability, while centrally positioned areas may contain more pores to promote permeability and elasticity.

In addition to pore density, pore size can also play an important role. Depending on the application, the size of the pores can be adjusted so that either larger pores facilitate air and liquid transport and/or smaller pores optimize adhesion and mechanical stability.

The combination of pore density and pore size can enable flexible adaptation of the connecting layer to specific requirements.

For applications with high loads, the pore density in load-bearing areas could be reduced, while less loaded areas are made more porous.

In situations where water or vapor permeability is critical, a uniformly high pore density can be selected.

It is also possible that the connecting layer and/or the elastic layer comprise an integral foam. The connecting layer may have pores with a larger diameter, preferably in the area of the elevations, whereas the elastic layer, which is not intended for connection to a concrete railroad tie, has no or very few pores.

The railroad ties may be designed as simple ties, frame ties, ear ties, U-ties, etc.

It is preferable that the under sleeper pad has a density in the range of 100 to 1200 kg/m3, preferably in the range of 150 to 800 kg/m3, and particularly preferably in the range of 200 to 500 kg/m3.

The density can be crucial for several reasons that are closely related to the specific requirements of railway infrastructure.

An optimally adjusted density for under sleeper pads can contribute to an ideal balance between damping, stability, and/or durability of the railroad tie.

Of course, it may also be the case that the density within an under sleeper pad is not uniform, in other words, that it varies. A variation in the density of the under sleeper pad can be advantageous depending on its function and design.

The density may vary depending on requirements.

In preferred exemplary embodiments, the connecting layer and the elastic layer are intended to be formed in one piece with one another.

The term "in one piece" means in particular that the connecting layer and the elastic layer form a continuous layer or a single unit.

The one-piece design may lead to improved stability of the under sleeper pad, as the elastic layer and the connecting layer are fixedly connected to each other by way of the one-piece design. However, the one-piece design can also make the under sleeper pad easier to manufacture.

It is preferable that some of the elevations, preferably all of the elevations, have a ratio of transverse extent to longitudinal extent in a range of 1/10 to 1/1.75. The longitudinal extent of the diamond-shaped elevations is preferably in the range of 5 to 15 mm.

A ratio in the range of 1/10 to 1/1.75 can offer an ideal combination of mechanical strength, functionality, and/or material efficiency.

The elevations may allow slight elastic deformation along their longitudinal extent, which can dampen stresses and/or shocks, particularly in conjunction with railway tracks.

However, it is possible that the exact ratio of transverse extent to longitudinal extent of the elevation may vary depending on its position and function within the under sleeper pad.

It has been found that, in the case of elevations, a ratio of transverse extent to longitudinal extent in the range of 1/10 to 1/1.75 results in optimal connection of the connecting layer to the concrete railroad tie.

It is preferable that, in a plan view of the under sleeper pad, the directions of the longitudinal extent and/or the directions of the transverse extent and/or edges of a group of elevations, preferably all elevations, are parallel to each other.

A parallel alignment can help to distribute loads evenly across the surface of the under sleeper pad and transfer them to the supporting structure or the ballast bed.

However, parallel alignment of the elevations can also facilitate the production process through standardization and repeatability.

Manufacturing processes such as planing and/or milling processes for forming the elevations or producing the connecting layer can be implemented particularly easily and effectively due to the clearly defined diamond-shaped geometry of the elevations.

This flexible design option allows the under sleeper pad to be adapted to a wide range of technical and functional requirements.

The parallel arrangement of the elevations can play a key role in maximizing the performance and durability of the under sleeper pad.

The parallel structure and/or diamond shape of the elevations distribute forces particularly evenly across the connecting layer, thereby preventing local overloads and extending the service life of the under sleeper pad.

Since the elevations are diamond-shaped, it is conceivable that not all of the edges of the individual diamonds are parallel to each other, but only the edges of individual groups of elevations.

It is advantageous if the elevations have a height of 0.5 to 3.5 mm, preferably 0.6 to 3.0 mm, relative to an area of the connecting layer adjacent to the respective elevation.

Channels formed between adjacent elevations thus preferably have a depth of 0.5 to 3.5 mm, preferably 0.6 to 3.0 mm.

The height, spacing, and shape of the elevations can influence a tear-off value. In the course of this description, the tear-off value defines a value that describes how easy or difficult it is to tear the under sleeper pad off the railroad tie.

The minimum required tear-off values can be found in the IRS-70713-1-2ed-en standard.

Other standards that can be used in this regard are IG04013_V1_14082018_fil USP, RBGL-TRA-SPC-R-00002 1.9, RFI TCAR SF AR 03 008 A Manufatti in CLS con TAPPETINI USP 31_8_2015, and/or the ÖBB under sleeper pad testing system.

It is preferable that the distance between the edges of two adjacent elevations is at least half and at most ten times the transverse extent of the respective elevation. The distance between the edges of two adjacent elevations corresponds to the width of the channel between these two elevations.

The channels of the connecting layer between the elevations are filled with the concrete of the railroad tie, which has not yet cured, when the under sleeper pad is secured to the railroad tie.

It is preferable that at least 15% and at most 50% of the total area of the connecting layer is formed by the elevations.

This coverage value ensures balanced force transmission and load distribution on the under sleeper pad, which supports the stability and/or durability of the connecting layer.

It is preferable that the connecting layer and/or the elastic layer comprise or consist of an elastomer, preferably a foamed elastomer.

Alternatively, the connecting layer and/or elastic layer may also be formed from a thermoplastic. The choice of material is made depending on the different intended uses or load scenarios of the under sleeper pad.

It is possible that the under sleeper pad is provided with reinforcement, for example made of a metal material such as steel, brass, or the like, and/or a fibrous material, in particular in the form of short fibers with a fiber length that varies depending on the under sleeper pad.

The elastomer is preferably a polyurethane. Alternatively, the elastomer can also be a rubber, in particular natural rubber, or a mixture of polyurethane and rubber, possibly also with other materials.

The edges of the elevations pointing away from the elastic layer may be designed as a chamfer and/or a rounding. The resulting beveled surfaces help the concrete to collect sufficiently in the channels between the elevations.

The chamfer may be a beveled surface that runs at an angle of 15° to 45° to the height of the elevations. This chamfer prevents sharp edges and distributes the load more evenly at the transitions.

It is possible to form the connecting layer, in particular the elevations, by means of a planing and/or milling operation.

In addition to the under sleeper pad according to the invention, the invention therefore also provides a method for producing an under sleeper pad according to the invention, in which the connecting layer, in particular the elevations, is or are formed by means of a planing operation and/or a milling operation.

Alternatively or in addition to the planing and/or milling operation, the connecting layer, in particular the elevations, can be formed by means of a laser operation.

Regardless of whether a planing, milling, or laser operation is used, it may be provided that the corresponding tools or devices are guided along straight paths through the connecting layer during the respective process in order to remove material and thus create the elevations between these paths. The straight paths can be aligned at such an angle to each other that, when viewed from above, the elevations ultimately form a diamond shape.

A wedge-shaped cross-section of the under sleeper pad can prevent the formation of air bubbles between the railroad tie and the under sleeper pad when the under sleeper pad is connected to the railroad tie. To avoid such air bubbles, it is particularly preferable that the under sleeper pad is thicker in the middle than at its edges when viewed in cross-section. With such designs, the under sleeper pad can thus have a wedge-shaped cross-section towards both edges.

When connecting the under sleeper pad to the railroad tie that has not yet cured, the connecting layer with its elevations is preferably vibrated into the still soft concrete or the other still soft, flowable material of the railroad tie.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and details of preferred embodiments of the inventions are explained by way of example in the following description of the figures. They show:

FIG. 1: a representation of railroad ties with under sleeper pads according to the invention along a section of track;

FIG. 2: a perspective view of the under sleeper pad according to FIG. 1;

FIG. 3: a detailed representation of the under sleeper pad according to FIGS. 1 and 2;

FIG. 4: a cross-sectional view of the under sleeper pad;

FIGS. 5-6: illustrations of different variants of the under sleeper pad elevations;

FIG. 7: a schematic representation of the geometry of the elevations;

FIG. 8: a schematic representation of the production process for the connecting layer; and

FIGS. 9-10 illustrations of the arrangement of the elevations of an under sleeper pad.

 DETAILED DESCRIPTION

FIG. 1 shows a schematic representation of a section of track in a side view. Concrete railroad ties 5 with a rail arranged above them can be seen. An under

sleeper pad 1 according to the invention is connected to each of the outer surfaces 3, in this case specifically to the undersides 4, of the railroad ties 5. These under sleeper pads 1 embed the railroad ties 5 in the ballast bed 2. The vibration-damping effect of under sleeper pads 1 is well known, as is their ballast-protecting effect. The elastoplastic properties of under sleeper pads 1 according to the invention can also be adapted to the respective requirements in a manner known per se.

It is conceivable that the railroad tie 1 comprises a material other than concrete, as already explained at the outset.

When connected to the railroad tie 5, the connecting layer 7 of the under sleeper pad 1 is not visible, see FIG. 1, because the elevations 8 of the connecting layer 7 engage with the concrete body of the respective railroad tie 1, thereby securing the respective under sleeper pad 1 to the respective railroad tie.

FIG. 2 shows a plan view of an under sleeper pad 1 according to the invention, as can be used in FIG. 1, detached from the railroad tie 1. It is shown that the under sleeper pad 1 comprises an elastic layer 6 and a connecting layer 7. The elevations 8 of the connecting layer 7, which are diamond-shaped in a plan view according to the invention, can be clearly seen in FIG. 2. The longitudinal extent 14 of the diamonds is greater than their transverse extent 13, as can be seen particularly well in FIG. 7, which is explained further below.

FIG. 2 also shows that a channel 17 is arranged between each of the individual elevations 8. The channels 17 are filled with the concrete of the railroad tie 5 when the under sleeper pad 1 with the elevations 8 of the connecting layer 7 is pressed, preferably vibrated, into the not yet cured concrete of the railroad tie 5.

FIG. 2 shows that the connecting layer 7 has a large number of elevations 8. In this preferred exemplary embodiment, all elevations 8 have a diamond shape in plan view. However, as explained at the outset, this does not necessarily have to be the case.

The elevations 8 result in a large surface area of the connecting layer 7, which is then fixed in a form-fitting manner with its elevations 8 in the cured concrete of the finished railroad tie 5. It is preferred that the elevations 8 and the areas 9 of the connecting layer 7 between the elevations 8 have a porosity that is open to the outside.

This creates a particularly large surface area for a particularly firm connection of the under sleeper pad 1 to the railroad tie 5.

FIG. 2 also shows that, in preferred exemplary embodiments such as this one, the connecting layer 7 and the elastic layer 6 of the under sleeper pad 1 are formed in one piece with each other.

It is of course also conceivable that the under sleeper pad 1 has a reinforcement and/or reinforcement, although this is not shown in the Figures.

The reinforcement can also be flat, rod-shaped, grid-shaped, or in the form of fibers, etc.

FIG. 3 shows a detailed view of a corner section of the under sleeper pad 1 from FIG. 2. Here it can be seen that the elevations 8 and/or the areas of the connecting layer 7 arranged between the elevations 8 have a porosity that is open to the outside. It can also be clearly seen that in this preferred exemplary embodiment, the elastic layer 6 also has an outwardly open porosity.

For the sake of completeness, it should be mentioned that the porosity of the under sleeper pad 1 is shown by a dotted line on the under sleeper pad 1 in FIG. 3.

It is preferred that the connecting layer 7 has 5 to 500 pores per mm2 on its surface, preferably 20 to 350 pores per mm2, and particularly preferably 35 to 250 pores per mm2.

For the sake of simplicity, not all pores are shown in FIG. 3. However, FIG. 3 shows the height 29 of the elevations 8 relative to the area of the connecting layer 7 adjacent to the respective elevation 8. This height 29 is preferably in a range of 0.5 mm to 3.5 mm, particularly preferably from 0.6 mm to 3.0 mm.

For the sake of completeness, it should be noted that the connecting layer 7 and the elastic layer 6 do not necessarily have to be formed in one piece and do not necessarily have to be made of the same material. They may also be layers connected to each other, e.g., by bonding, which may also be made of different materials and have different porosities.

FIG. 4 shows a preferred variant of the under sleeper pad 1. As shown here, in order to avoid air bubbles between the cured railroad tie 5 and the under sleeper pad 1, it may be provided that the under sleeper pad 1, viewed in cross-section, is thicker

in its center 9 than at its edges 25. In such embodiments, the under sleeper pad 1 can thus have a wedge-shaped cross-section tapering towards both edges 25, as can be seen in FIG. 4. Preferably, the wedge-shaped cross-section has a wedge angle 30 in the range of 1° to 10°. This allows air to escape more easily towards the edges 25 when the elevations 8 are inserted, preferably by vibrating, into the still soft concrete of the railroad tie 5, so that no undesirable air pockets or air bubbles occur. Vibrating is preferably carried out with a vibrating roller.

In addition to or as an alternative to the wedge-shaped cross-section, the under sleeper pad 1 may also have perforations or ventilation channels 28 running away from the connecting layer 7 and through the elastic layer 6, through which air can escape in order to prevent the aforementioned air pockets or air bubbles. The ventilation channels 28 may, for example, have an opening diameter in the range of 0.1 to 1 mm.

The channels 17 between the elevations 8 of the connecting layer 7, which have already been mentioned several times, could also be referred to as intermediate channels 17 for even better differentiation from the ventilation channels 28.

FIGS. 5 and 6 show representations of the elevations 8 of the connecting layer 7 in preferred variants.

FIG. 5 shows a variant of an elevation 8 according to the invention, wherein the edges 10 are formed as a rounding 12.

FIG. 6 shows a further variant of an elevation 8 according to the invention, wherein the edges 10 are formed as chamfers 11.

FIG. 7 shows a plan view and thus illustrates the diamond shape of the elevations 8 and their preferred arrangement relative to each other.

FIG. 7 shows the longitudinal extent 14 and the transverse extent 13 of the elevations 8.

It can be seen that the directions 27 of the longitudinal extents 14 and the directions 26 of the transverse extents 13 of the individual elevations 8 are aligned parallel to each other in preferred variants, as shown here.

It can also be seen that edges 10 of the elevations 8 in preferred variants can also be parallel to each other.

FIG. 8 shows a method for producing the elevations 8 and thus for producing the connecting layer 7. A first device 23 and a second device 24 are shown, which form the channels 17 and thus the elevations 8. The devices 23 and 24 may be material-removing tools, preferably planer heads, milling heads, or even laser heads.

The first device 23 and the second device 24 may be the same device or different devices.

It is therefore possible that the first device 23 and the second device 24 are used to perform a planing operation and/or a milling operation, respectively, whereby the connecting layer 7, in particular the elevations 8, is or are formed.

The first device 23 and the second device 24 may be moved simultaneously or with a time delay along the first direction 21 and the second direction 22 in order to form the diamond-shaped elevations 8.

It is possible that the planing operation and/or the milling operation are performed fully automatically or semi-automatically.

Regardless of whether it is a planing, milling, or laser operation, it may be provided that the corresponding tools or devices 23 and 24 are guided along straight paths or directions 21 and 22 through the connecting layer 7 during the respective operation in order to remove material and thus create the elevations 8 between these paths. The channels 17 are created along these paths by removing material. The straight paths or directions 21 and 22 can be aligned at such an angle to each other that, when viewed from above, the elevations 8 ultimately form a diamond shape.

The elevations 8 may have frayed edges 10 if they are produced by a planning operation.

It is possible that the elevations 8, when produced by the milling operation, may have a bevel at the end of the respective longitudinal extent 14 of the elevation 8.

FIG. 9 and FIG. 10 illustrate examples of the distances between the elevations 8, wherein the distances in FIG. 9 and the distances in FIG. 10 are of different sizes, in other words, of different dimensions.

FIG. 9 shows a first distance 15, a second distance 18, and a third distance 19.

In the variant according to FIG. 9, the first distance 15 is 2 mm. The second distance 18 is 4 mm and the third distance 19 has a value of 3 mm.

FIG. 10 shows a first distance 15 of 20 mm, a second distance 18 of 40 mm, a third distance 19 of 20 mm, and a fourth distance 20 of 40 mm.

The distances 15, 18, 19, and 20 illustrated in FIGS. 9 and 10 are, of course, only preferred embodiments and may also have completely different values. In any case, it is preferred that the distance 15 between the edges 10 of two adjacent elevations 8 be at least half and at most ten times the transverse extent 13 of the respective elevation 8. The distance 15 between the edges 10 of two adjacent elevations 8 corresponds to the width of the channel 17 between these two elevations.

Key for the Reference Numerals:

1 under sleeper pad

2 ballast bed

3 outer surface

4 underside

5 railroad tie

6 elastic layer

7 connecting layer

8 elevation

9 center

10 edge

11 bevel

12 rounding

13 transverse extent

14 longitudinal extent

15 first distance

16 rail

17 channel

18 second distance

19 third distance

20 fourth distance

21 first direction

22 second direction

23 first device

24 second device

25 edge

26 direction

27 direction

28 ventilation duct

29 height

30 wedge angle

Claims

1. An under sleeper pad for connection to an outer surface facing a ballast bed of a concrete railroad tie, the under sleeper pad comprising:

an elastic layer; and
a connecting layer that is adapted to connect the under sleeper pad to the railroad tie, the connecting layer having a plurality of elevations for embedding in concrete of the concrete railroad tie, wherein in a plan view of the under sleeper pad, at least some of the elevations have a diamond shape, and the diamond shape has a greater longitudinal extent than transverse extent.

2. The under sleeper pad as claimed in claim 1, wherein at least one of the connecting layer or the elastic layer comprise a porous material.

3. The under sleeper pad as claimed in claim 1, wherein the under sleeper pad has a density in a range of 100 to 1200 kg/m3.

4. The under sleeper pad as claimed in claim 1, wherein the connecting layer and the elastic layer are formed in one piece with each other.

5. The under sleeper pad as claimed in claim 1, wherein at least one of the elevations or areas of the connecting layer between the elevations have a porosity that is open to an outside.

6. The under sleeper pad as claimed in claim 1, wherein the connecting layer has 5 to 500 pores per mm2.

7. The under sleeper pad as claimed in claim 1, wherein some of the elevations have a ratio of the transverse extent to the longitudinal extent in a range of 1/10 to 1/1.75.

8. The under sleeper pad as claimed in claim 1, wherein, in the plan view of the under sleeper pad, at least one of a) directions of the longitudinal extent of a group of elevations are parallel to each other, b) directions of the transverse extent of a group of elevations are parallel to each other, or c) edges of a group of elevations are parallel to each other.

9. The under sleeper pad as claimed in claim 1, wherein the elevations have a height of 0.5 to 3.5 mm relative to an area of the connecting layer adjacent to the respective elevations.

10. The under sleeper pad as claimed in claim 1, wherein the distance between edges of two adjacent ones of the elevations is at least half and at most ten times the transverse extent of the respective elevations.

11. The under sleeper pad as claimed in claim 1, wherein at least 15% and at most 50% of a total area of the connecting layer comprises the elevations.

12. The under sleeper pad as claimed in claim 1, wherein at least one of the connecting layer or the elastic layer comprises an elastomer.

13. The under sleeper pad as claimed in claim 12, wherein the elastomer is a foamed elastomer.

14. The under sleeper pad as claimed in claim 12, wherein the elastomer is a polyurethane.

15. The under sleeper pad as claimed in claim 1, wherein edges of the elevations pointing away from the elastic layer are formed as a chamfer.

16. The under sleeper pad as claimed in claim 1, wherein edges of the elevations pointing away from the elastic layer are formed as rounding.

17. A method for producing an under sleeper pad, the method comprising:

forming an elastic layer and a connecting layer that is adapted to connect the under sleeper pad to a railroad tie, the connecting layer having a plurality of elevations for embedding in concrete of the concrete railroad tie, wherein in a plan view of the under sleeper pad, at least some of the elevations have a diamond shape, and the diamond shape has a greater longitudinal extent than transverse extent; and
forming the elevations by at least one of a planing operation or a milling operation.
Patent History
Publication number: 20260201653
Type: Application
Filed: Jan 12, 2026
Publication Date: Jul 16, 2026
Applicant: Getzner Werkstoffe Holding GmbH (Bürs)
Inventors: Lukas WITWER (Tschagguns), Johannes WALCH (Lorüns), Andreas FRITSCHE (Ludesch), Vladica MLADENOVIC (Bludenz)
Application Number: 19/446,260
Classifications
International Classification: E01B 3/36 (20060101);