NL2015782B1

NL2015782B1 - Railway switch of a railway track

Info

Publication number: NL2015782B1
Application number: NL2015782A
Authority: NL
Inventors: Annee Bos Jelte; Hendrik Veldsink Gerrit; Aloysius Maria Jansen Jozef
Original assignee: Movares Nederland Bv; Koninklijke Bam Groep Nv
Priority date: 2015-11-12
Filing date: 2015-11-12
Publication date: 2017-05-31

Abstract

Railway switch or crossing of a railway track comprising rails mounted on sleepers that are resting on ballast, wherein at the switch sleepers are provided for supporting said rails and optionally also point rails, wherein said sleepers at the switch are embodied with an upper part and a lower part that occupy a distance with respect to each other that is vertically adjustable, and wherein the rails are mounted on the upper part and the lower part is resting on said ballast.

Description

Railway switch of a railway track

The invention relates to a railway switch or crossing of a railway track comprising rails mounted on sleepers that are resting on ballast, wherein the rails at the switch are also provided with sleepers for supporting said rails and optionally point rails forming part of the crossing. The invention also relates to such a separate sleeper. EP-A-2 339 068 addresses the known problem of railways that the support of neighbouring or adjacent straight railway parts may vary depending on the deterioration of the ballast, particularly although not exclusively shortly after establishing a new railway. The problem is also existent with older railways, and is connected with the deterioration of the supporting structure of the sleepers which may be different for the first railway part and the adjacent second railway part. The problem is particularly prominent when the first railway part rests on ballast, and the second adjacent railway part rests on a more fixed structure such as concrete, as may be the case at a railway crossing. The problem exists however also at said railway crossing when the crossing is entirely supported by ballast. Over time the ballast may become more dense, and this deterioration is promoted by the regularly passing trains, which in turn will result in accelerated den-sification of the ballast. The ballast getting more dense may result in that the sleepers at the crossing will eventually no longer be supported by the ballast, but will be hanging from the rail. This is very detrimental to passenger comfort, and may result in rail failure or even a derailment of a passing train at the crossing. A known solution is to add material to the ballast to compensate for its densification. This is however costly and it is no endurable solution, since it must be frequently repeated .

It is an object of the invention to provide an alternative and low-cost solution to address this problem.

According to the invention a sleeper and a railway switch or crossing is proposed having the features of one or more of the appended claims.

In a first aspect of the invention the sleepers at the switch or crossing are embodied with an upper part and a lower part that occupy a distance with respect to each other that is vertically adjustable, wherein the rails are mounted or mountable on the upper part and the lower part is resting or intended to be resting on said ballast. This makes adding material to the ballast, which is the common and expensive way of addressing this problem in the prior art, unnecessary. A beneficial aspect is further that adjusting the elevation of the upper part on which the rails at the crossing rest, can be executed quickly without much adverse effects for the daily train schedule.

Suitably the upper part and the lower part of the sleeper are U-shaped such that when assembled together they define a space delimited by said upper part and lower part, and that at least within said space height adjustment means are provided. The space height adjustment means can be selected from many feasible options, such as hydraulic or pneumatic adjustment means, or electrically powered adjustment means.

In a preferred embodiment the height adjustment means are embodied with a first plate extending in the space's length and supported along its length by the lower part, which first plate is provided with wedge shaped upstanding notches, and that the upper part's underside is equipped with wedge shaped recesses, wherein said notches and recesses have engaging surfaces that arrange that the upper part's upper side is parallel to the lower part's underside, and that the said first plate is movable in the length of the lower part so as to adjust the elevation of the upper part with respect to the under part. These mechanical adjustment means are reliable, require little maintenance if any at all, and are the epitome of low-cost.

It is preferred that the upper part and the lower part are equipped with resistance means that prevent vertical movement of the upper part with respect to the lower part.

Suitably therefore the resistance means comprise bolts extending from the lower part upwards into and through apertures in bottoms of receptacles connected to and extending downwards from the upper part, wherein the bottoms of the re ceptacles are spring-loaded with springs coiled around said bolts extending through and into the receptacles such that upward movement of the upper part away from the lower part is counteracted. Spring loading is suitably done by nuts mounted on the said bolts.

Although in many cases it suffices to equip the railway switch or crossing of the invention with one or more of the features as discussed hereinabove, occasionally and particularly with broad railway crossings, it may be preferable that on top and near to a center of the first plate a second plate is provided that is movable with respect to the first plate, wherein the second plate is also provided with wedge shaped upstanding notches that cooperate with wedge shaped recesses at the upper part's underside, so that longitudinal displacement of the second plate with reference to the first plate provides for adjustment of the elevation of a center portion of the upper part with respect to a center portion of the under part. With these features a solution is provided for the practical problem that the densification of the ballast may be different along the width of the railway track, which is particularly possible when a number of railway tracks are present next to each other at the railway crossing.

Particularly with a broad railway crossing it is preferable that the lower part is equipped with one or more hinges to enable that said lower part's underside adjusts to the superficial shape of the ballast.

The ease of adjustment of the elevation of the upper part is particularly promoted by the feature that the first plate and/or the second plate are provided with a longitudinally extending pin that is moved through an aperture in an upstanding immovable adjustment plate that is for instance mounted on the lower part, wherein the longitudinally extending pin is adjustable with reference to the upstanding adjustment plate.

Preferably the longitudinally extending pin is provided with screw thread for receiving a nut or for cooperating with a corresponding screw thread in the aperture of the immovable upstanding adjustment plate.

In order to enable independent adjustment of the first plate and the second plate it is preferred that the first plate and the second plate are both equipped with a longitudinally extending pin, and that these respective pins are provided on opposite sides of the plates.

In another aspect of the invention the upper part is provided with one or more accelerometers for measuring acceleration of said upper part during passage of a train. If the measured acceleration exceeds a certain level this may be taken as a signal that readjustment of the elevation of the upper part is required.

The invention will hereinafter be further elucidated with reference to the drawing of an exemplary embodiment of a sleeper for a railway switch or crossing according to the invention, and that is not limiting as to the appended claims.

In the drawing: - figures 1A - 1C show a first embodiment of a sleeper according to the invention in respectively a top view, a cross-sectional frontal view, and a cross-sectional side view; - figures 2A - 2C show in a side view, a top view, and a bottom view respectively an upper part of the sleeper according to figures 1A - 1C; - figures 3A and 3B show in a top view and in a side view respectively a plate forming part of the sleeper according to figures 1A - 1C; - figures 4A and 4B show a lower part of the sleeper according to figures 1A - 1C; and - figures 5A - 5D show constituent parts of a second embodiment of a sleeper according to the invention in a side view only, notably an upper part, a first plate and a second plate, and a lower part.

Whenever in the figures the same reference numerals are applied, these numerals refer to the same parts.

The skilled person, if not every layman, is particularly aware and knowledgeable with the fact that a railway switch or crossing of a railway track comprises rails mounted on sleepers that are resting on ballast. This subject matter is therefore not shown in the drawings since it does not impair the skilled person to operate according to the invention as disclosed herein in any way. The skilled person also knows that at the switch or crossing sleepers may be provided for supporting said rails and optionally point rails, and therefore also this is not shown in the drawing of the figures.

The drawing of the figures concentrate on showing the features of the sleeper 1 of the invention that is to be used in connection with a switch or railway crossing. A first embodiment of the sleeper 1 of the invention is shown in figures 1A - 1C in a top view, a frontal cross-sectional view, and a cross-sectional side view respectively. In this first embodiment the sleeper 1 is embodied with an upper part 2 and a lower part 3 that can occupy a distance with respect to each other that is vertically adjustable. The rails of the railway track are to be mounted on the upper part 2 at the locations indicated with reference 4, and the lower part 3 is to be resting on ballast.

As can be particularly seen in figure IB the upper part 2 and the lower part 3 are essentially U-shaped such that when assembled together they define a space 5 delimited by said upper part 2 and lower part 3. It is at least within said space 5 that height adjustment means are provided.

The height adjustment means are embodied with a first plate 6 (which is separately shown in figures 3A and 3B in a top view and side view respectively), which plate 6 extends in the length of the space 5 and is supported along its length by the lower part 3 as can be seen in figure 1C. This first plate 6 is provided with wedge shaped upstanding notches 7 which can be best seen in figure 3B. Correspondingly the underside of the upper part 2 is equipped with wedge shaped recesses 8 as is best shown in figure 2A relating to a side view of a separate upper part 2. Said notches 7 on the first plate 6 and said recesses 8 at the underside of the upper part 2 have engaging surfaces that arrange that the upper part's upper side will always be parallel to the lower part's underside. The said first plate 6 (separately shown in figures 3A and 3B) is further movably provided along the length of the lower part 3 as is shown in figure IB and 1C, so as to enable adjusting the elevation of the upper part 2 with respect to the under part 3.

From figure 1C it is clear that the upper part 2 and the lower part 3 are equipped with resistance means 5' , 5'', 5''' that prevent vertical movement of the upper part 2 with respect to the lower part 3. The resistance means 5', 5'', 5''' comprise bolts and 5' extending from the lower part 3 upwards into and through apertures in bottoms of receptacles 5'' connected to and extending downwards from the upper part 2, wherein the bottoms of the receptacles 5'' are spring-loaded with springs 5''’ coiled around said bolts 5' extending through the apertures into said receptacles 5'' such that vertical movement of the upper part 2 upward and away from the lower part 3 is counteracted.

In figures 3A and 3B it is shown that the first plate 6 is provided with a longitudinally extending pin 9 that can be moved through an aperture 10 in an immovable upstanding adjustment plate 11 that is in this embodiment mounted in the lower part 3 as is best seen in figure 4B. The longitudinally extending pin 9 that is connected to the plate 6 is adjustable with reference to the up-standing adjustment plate 11 that is mounted on or in the lower part 3. Suitably therefore the longitudinally extending pin 9 is provided with screw thread for receiving a nut or for cooperating with a corresponding screw thread in the aperture 10 of the upstanding adjustment plate 11. By changing the extent at which the pin 9 reaches through the aperture 10 of the adjustment plate 11 a longitudinal displacement of the plate 6 with reference to the remainder of the sleeper 1 is effectuated, which results into a vertical displacement of the upper part 2 with reference to the lower part 3 due to the cooperating engaging surfaces of the wedge-shaped notches 7 of the first plate 6, and the wedge shaped recesses 8 at the underside of the upper part 2. Correspondingly the upper surface of the upper part 2 on which the rails are mounted at reference 4 can be placed at the proper elevation to adequately support said rails and avoid that the rails and its supporting construction are subjected to forces that are caused by passing trains and which are to be avoided. A number of constituent parts of a second embodiment of the sleeper of the invention that is applicable to broader railway switches or crossings embodied with several railways, are shown in figures 5A - 5D. These figures 5A - 5D show side views only of the upper part 2 (see figure 5A), the first plate 6 with its wedge-shaped notches 7 and longitudinally extending pin 9 (see figure 5C), and the lower part 3 (see figure 5 D) of the sleeper of the second embodiment. In this second embodiment on top and near to a center of the first plate 6 a second plate 6' can be provided that is movable with respect to the first plate 6. Also this second plate 6' is provided with wedge shaped upstanding notches 7' that are intended to cooperate with wedge shaped recesses 8' at the underside of the upper part 2, so that longitudinal displacement of the second plate 6' with reference to the first plate 6 provides for independent adjustment of the elevation of a center portion of the upper part 2 with respect to a center portion of the under part 3. For that purpose also this second plate 6' is equipped with a longitudinally extending pin 9' which can be operated for moving the second plate 6' in its longitudinal direction .

In combination with the first plate 6 that is provided with the longitudinally extending pin 9, it is thus possible to use this pin 9 of the first plate 6 for simultaneous and longitudinal movement of the wedge-shaped notches 7 of both the first plate 6 and the wedge-shaped notches 7' of the second plate 6', so that these notches 7, 7' simultaneously and likewise operate on the corresponding wedge shaped recesses 8, 8' at the underside of the upper part 2. In this way the elevation of the entire upper part 2 can be adjusted along its entire length. By only operating the pin 9' of the second plate 6' it is then possible to separately adjust the elevation of the middle or center of the upper part 2, since then only the wedge-shaped notches 7' of the second plate 6' are displaced and correspondingly act on the engaging wedge shaped recesses 8' of the upper part 2. To enable such independent operation of the pin 9 of the first plate 6 and the pin 9' of the second plate 6', it is preferable that these respective pins 9, 9' are provided on opposite sides of the plates 6, 6' .

Figure 5D further shows that the lower part 3 is equipped with one or more hinges 12 to enable that said lower part's underside adjusts to the ballast. A further beneficial feature which is helpful in monitoring the condition of the railway switch or crossing of the invention is that the upper part 2 is provided with one or more accelerometers 13 as shown in figure 5A, for measuring the acceleration of said upper part 2 during passage of a train. When indeed notable accelerations are measured this is an indication that adjustment of the upper part 2 is required to adapt its elevation with reference to the lower part 3 and to re-establish that this lower part 3 is properly supported by the ballast.

Although the invention has been discussed in the foregoing with reference to an exemplary embodiment of the sleeper of the invention and the railway crossing or switch to which it is applied, the invention is not restricted to this particular embodiment which can be varied in many ways without departing from the invention. The discussed exemplary embodiment shall therefore not be used to construe the appended claims strictly in accordance therewith. On the contrary the embodiment is merely intended to explain the wording of the appended claims without intent to limit the claims to this exemplary embodiment. The scope of protection of the invention shall therefore be construed in accordance with the appended claims only, wherein a possible ambiguity in the wording of the claims shall be resolved using this exemplary embodiment.

Claims

1. Railway switch or crossing of a railway track comprising rails mounted on sleepers that are resting on ballast, wherein at the switch sleepers {1) are provided for supporting said rails and optionally also point rails, characterized in that said sleepers (1) at the switch are embodied with an upper part (2) and a lower part (3) that occupy a distance with respect to each other that is vertically adjustable, wherein the rails are mounted or mountable on the upper part (2) and the lower part (3) is resting or intended to be resting on said ballast,

2. Railway switch or crossing according to claim 1, characterized in that the upper part (2) and the lower part (3) of the sleeper (1) are U-shaped such that when assembled together they define a space (5) delimited by said upper part (2) and lower part (3), and that at least within said space (5) height adjustment means (7, 8} are provided.

3. Railway switch or crossing according to claim 2, characterized in that the height adjustment means are embodied with a first plate (6) extending in the space's length and supported along its length by the lower part (3), which first plate (6) is provided with wedge shaped upstanding notches (7), and that the upper part's underside is equipped with wedge shaped recesses (8), wherein said notches (7) and recesses (8) have engaging surfaces that arrange that the upper part's upper side is parallel to the lower part's underside, and that the said first plate (6) is movable in the length of the lower part (3) so as to adjust the elevation of the upper part (2) with respect to the under part (3).

4. Railway switch or crossing according to any one of the previous claims 1-3, characterized in that the upper part (2) and the lower part {3) are equipped with resistance means (5', 5'', 5''') that prevent vertical movement of the upper part (2) with respect to the lower part (3).

5. Railway switch or crossing according to claim 4, characterized in that the resistance means (5', 5'', 5''') comprise bolts (5') extending from the lower part (3} upwards into and through apertures in bottoms of receptacles (5'') connected to and extending downwards from the upper part (2), wherein the bottoms of the receptacles (5") are spring-loaded with springs (5''') coiled around said bolts (5') extending into the receptacles (5'' ) such that upward movement of the upper part. (2) away from the lower part (3) is counteracted.

6. Railway switch or crossing according to any one of the previous claims 3 - 5, characterized in that on top and near to a center of the first plate (6) a second plate (6') is provided that is movable with respect to the first plate (6), wherein the second plate (6') is provided with wedge shaped upstanding notches (7') that cooperate with wedge shaped recesses (8') at the upper part's underside, so that longitudinal displacement of the second plate (6') with reference to the first plate (6} provides for adjustment of the elevation of a center portion of the upper part (2} with respect to a center portion of the under part (3).

7. Railway switch or crossing according to claim 6, characterised in that the lower part (3) is equipped with one or more hinges (12) to enable that said lower part's underside adjusts to the ballast.

8. Railway switch or crossing according to any one of claims 3-7, characterized in that the first plate (6) and/or the second plate {6') are provided with a longitudinally extending pin (9, 9') that is moved through an aperture (10) in an immovable upstanding adjustment plate (11, 11'), wherein the longitudinally extending pin (9, 9') is adjustable with reference to the upstanding adjustment plate (11, 11'}.

9. Railway switch or crossing according to claim 8, characterized in that the longitudinally extending pin ¢9, 9') is provided with screw thread for receiving a nut or for cooperating with a corresponding screw thread in the aperture (10) of the upstanding adjustment plate (11)-

10. Railway switch or crossing according to claim 8 or 9, characterized in that wherein the first plate (6) and the second plate (6') are both equipped with a longitudinally extending pin (9, 9'), these respective pins (9, 9') are provided on opposite sides of the plates (6, 6';.

11. Railway switch or crossing according to any one of the previous claims 1-10, characterised in that the upper part {2) is provided with one or more accelerometers (13} for measuring acceleration of said upper part (2) during passage of a train.

12. Sleeper (1) for a railway switch or crossing described as part of the railway switch or crossing according to any one of the previous claims 1-11.