MOBILE DUAL GAUGE CHANGING PLATFORM FOR RAILWAY AXLES

Abstract

Dual mobile track gauge changing platform (1) for railway axles configured to be installed between two straight track sections, comprising: a frame (2) equipped with wheels (21) oriented transversely to the direction of travel of the train; a displacement means (3) configured to move the frame (2) transversely between a first position and a second position, a gauge changer (4) disposed on the frame (2) which, when the frame (2) is in the first position, is located between the two straight track sections, wherein said gauge changer (4) comprises: - essentially longitudinal input rails (41) at the ends of the changer with a different track gauge at each end, - guide elements (42) on which the wagon slides when passing through the changer supporting its weight during the wheel gauge change process, and - wheel guides (43) arranged longitudinally to force the displacement of both wheels of the train along their own axis so that they adapt from the input track gauge to the new output gauge regardless of the direction of entry of the train to the changer; and characterized in that it further comprises a straight track section (5) arranged on the frame (2) which, when the frame (2) is in the second position, is located between the two track sections, said straight track section (5) comprising a pair of straight parallel rails (51, 52).

Description

Mobile dual-gauge track changing platform for railway axles OBJECT OF THE INVENTION The invention belongs in general to the field of railways, and more particularly to railway gauge changing technology. The object of the present invention is a platform installed on a section of railway track to allow the axle gauge of a train to change or, alternatively, to allow the passage of a train without changing gauge. BACKGROUND OF THE INVENTION Different track gauges currently coexist on railway networks. For example, the Spanish railway network includes, among others, the Iberian gauge (1668 mm) and the international gauge (1435 mm). For this reason, systems have been developed to allow a train to move from a section of the railway network with one gauge to a section with a different gauge. These systems primarily consist of two distinct parts: a gauge-changing mechanism implemented on the train's bogie; and a gauge-changing platform located on a section of track. Each of these elements is described in more detail below, very briefly. Width change mechanism The axle gauge-changing mechanism consists of a series of mechanically connected elements that allow the train's axle wheels to move along the axle in a controlled manner, moving closer together or further apart to adapt to at least two track gauges. Gauge-changing mechanisms also have means for locking the wheels in the desired track gauge. More specifically, a gauge-changing mechanism is fitted to an axle or half-axle, depending on the technology, and consists of two sliding wheels that can change position and locking mechanisms that ensure the wheels cannot move while traveling along the track. Upon entering the gauge changer, the bogie or wagon frame rests on the changer and is guided longitudinally through it. Once in place and the wheels are relieved of the wagon's weight, they are unlocked using various methods depending on the technology's design. At this point, the wheels can move longitudinally along the axle, perpendicular to the train's direction of travel, and are guided from the entry position for the first gauge to the second gauge at the exit of the changer. Finally, the wheels are locked again to secure them in the new position and ensure safe operation on the track. Width change platform The gauge-changing platform arranged on the tracks comprises a series of means designed, firstly, to unlock the ability of the wheels to move along the axle of the train, secondly, to cause the wheels to move along the axle from the initial track gauge to the target track gauge, and finally, to lock the position of the train wheels back into that target track gauge. To perform these actions, a gauge-changing platform essentially comprises two elements: unlocking mechanisms and rails / counter-rails. The unlocking mechanisms are positioned so that, as the train passes, they engage the bogie locks, thus unlocking the wheels. The counter-rails, in turn, push the wheels moving along the rails, forcing them to shift from the first gauge to the second gauge. Patent ES2842962 describes an example of a track gauge changing platform. Currently, there are different gauge-changing technologies, such as those known as MERCAVE, CAF, or Talgo. Each technology corresponds to a particular bogie design where the locking / unlocking mechanism, including the locking mechanism, differs. Different locking mechanism configurations mean that the configuration of the unlocking elements on the corresponding gauge-changing platform is also different. In this context, it is sometimes necessary to have two different gauge-changing systems on the same platform, so that one or the other can be selected depending on the needs. Currently, to prevent interference, this is achieved by placing them side by side on a mobile platform. By moving the platform laterally, the first gauge-changing system, or alternatively the second, can be positioned for use. Naturally, the lateral displacement distance of the platform will be greater than the track gauge. The main drawback of this configuration is its excessive space requirements. Indeed, the most common track gauges mentioned earlier are around 1500 mm. Furthermore, the two gauge-changing systems, positioned side-by-side, will require additional separation space both between themselves and from the sides of the installation, as various auxiliary components will be necessary. Ultimately, the total width of the installation is approximately 12400 mm, and the distance to change between the two platform positions can be around 3450 mm. The size of the installation has a significant impact on ease of transport and installation. Therefore, there is a need in this field for platforms that occupy less space. On the other hand, the currently available dual-gauge platforms have two gauge-changing systems. Single-gauge platforms with a single gauge-changing system are also known. In either case, this configuration has the drawback of preventing a train without gauge-changing technology from passing through either platform. DESCRIPTION OF THE INVENTION The inventors of the present invention have solved these problems by using a dual platform that supports a gauge changer and a straight section of track, where, moreover, the rails of the gauge changer and the straight section can be intertwined. That is, one of the rails of the straight section is located between the two main rails of the gauge changer (and, correspondingly, one of the two main rails of the gauge changer is located between the two rails of the straight section). This allows for a reduction in the platform's size and also in the distance the platform must travel to switch between the gauge changer and the straight section of track. Furthermore, the straight section of track allows any train to pass through the platform, regardless of whether or not it is equipped with gauge-changing technology. The invention describes a mobile track gauge changing platform for railway axles configured to be installed between two sections of conventional straight track, comprising fundamentally the following elements: a frame, a means of moving the frame, a track gauge changer arranged on the frame, and a straight section of track arranged on the frame. Each of these components is described in more detail below. a) Frame It is a unique frame equipped with wheels oriented transversely to the direction of travel of the train. The frame can have any configuration as long as it has sufficient rigidity to support the gauge changer and the straight section of track during train passage. For example, in a particularly preferred embodiment of the invention, the frame comprises a horizontal beam structure to which the gauge changer and the straight section of track are attached. b) Means of displacement The means of displacement is configured to move the frame transversely between a first position and a second position. In this context, the transverse direction is perpendicular to the longitudinal direction, which is the natural direction of travel of a train crossing the platform. In principle, any means of displacement capable of moving the frame between the two positions mentioned could be used, although actuators (for example, hydraulic cylinders) oriented transversely and connected between a fixed point and the frame are preferably used. The wheels will preferably move along rails transverse to the direction of travel of the train. c) Gauge changer The gauge changer is mounted on the frame so that, when the frame is in the first position mentioned above, it is located between the two sections of conventional straight track. In other words, in the first position, the rails of the conventional straight track adjacent to the platform are aligned with the rails of the gauge changer, so that a train crossing the platform passes through the gauge changer. The gauge changer can be of any of the technologies mentioned above, including (but not limited to) CAF, Talgo, or MERCAVE technology. In any case, the gauge changer comprises the following elements: - Essentially longitudinal input rails at the ends of the changer with a different track gauge at each end. - Guiding elements on which the wagon slides as it passes through the gauge changer, supporting its weight during the wheel width change process. - Wheel guides arranged longitudinally to force the movement of both train wheels along their own axis so that they adapt from the input track gauge to the new output gauge regardless of the direction of entry of the train to the gauge changer. The features described so far constitute part of the prior art in known mobile platforms. However, the platform of the invention differs from those in that it also comprises: d) Straight section of track This is a straight section of track mounted on the frame which, when the frame is in the second position, is located between the two sections of conventional track. This straight section of track comprises a pair of parallel straight rails which, in the second position, are aligned with the rails of the conventional straight track adjacent to the platform, so that a train passing through the platform can travel along the straight section of track without changing gauge. This configuration allows switching on the same platform between a gauge-changing system and, where necessary, a straight section of track. This is advantageous because it allows trains with bogies not equipped with gauge-changing technology to pass through the platform. Furthermore, according to a particularly preferred embodiment of the invention, the first rail of the straight track section is located between the two main rails of the gauge changer. Thus, to switch between the first and second positions, the frame is moved transversely a distance less than either of the two track gauges. This position of the first rail of the straight track section, however, constitutes an obstacle to the train's passage through the gauge changer. For this reason, in this preferred embodiment, the first rail is fixed to the frame by means of a hinge, so that it alternates between a horizontal folded position and a vertical extended position corresponding to its natural operating position. Thus, when the frame is in the first position corresponding to gauge change, an actuating means folds the first rail, which remains in a "lying" position to prevent it from interfering with the lower clearance of the wagons during the gauge change process. This configuration is advantageous because it allows for a significant reduction in the platform's size, thus facilitating its transport and installation. Naturally, the size of auxiliary elements, such as the pit in which the platform is installed, is also reduced. In principle, the first rail could be positioned anywhere between the two main rails of the gauge changer, for example, equidistant from both. However, the first rail of the straight section is offset from the two main rails of the gauge changer. Therefore, to switch between the first and second positions, the frame moves transversely a distance less than half the width of either of the two track gauges. Thanks to this configuration, the total width of the platform could be around 3250 mm. Furthermore, to switch between the first and second positions, it would only be necessary to move the platform laterally a distance of approximately 650 mm. Including space for auxiliary elements, the installation could have a width of approximately 7000 mm, almost half that of a conventional installation. The drive mechanism for folding the first rail of the straight track section can, in principle, have any configuration, provided it can move the first rail between the folded and unfolded positions. For example, in a particularly preferred embodiment, the drive mechanism comprises an actuator (e.g., a hydraulic cylinder) connected between the first rail of the straight track section and the frame such that, when actuated, it causes the first rail to fold or unfold. More preferably, the drive mechanism is connected to a base of the first rail of the straight track section such that, when retracted, it folds the first rail, and when extended, it unfolds the first rail. BRIEF DESCRIPTION OF THE DRAWINGS Figures 1A and 1B show a plan view of a mobile platform according to the present invention in the first and second positions respectively. Figs. 2A and 2B show a cross-sectional view of a mobile platform according to the present invention with the first rail of the straight track section respectively in the unfolded and folded positions. Figs. 3A and 3B show a cross-sectional view of the mobile platform along with the means of displacement respectively in the first and second positions. PREFERRED EMBODIMENT OF THE INVENTION An example of a mobile platform (1) according to the present invention is described below with reference to the attached figures. The mobile gauge-changing platform (1) is located inside a pit (not shown in the figures). The platform (1) comprises a frame (2) formed by a horizontal structure (22) of metal beams on which a gauge changer (4) and a straight section of track (5) are fixed. The structure (22) is supported on wheels (21) oriented transversely. The gauge changer (4) in this example is compatible with CAF's BRAVA technology and comprises input rails (41), main guide elements (42), and wheel guides (43). The input rails (41) are oriented essentially longitudinally at the ends of the gauge changer (4), with a first gauge corresponding to Iberian gauge (1668 mm) and a second gauge corresponding to standard gauge (1435 mm). These rails have a slight longitudinal incline towards the center of the platform to allow the axles to be suspended and unlocked. The main guide elements (42) consist essentially of a rail that runs the entire length of the platform. This rail has several assembled elements that help guide the wagon and support its weight.The wheel guides (43) are essentially made up of vertical plates arranged on both sides of the main rails (41) in the section where the gauge change occurs, thus forcing the train wheels to follow this path. The straight section of track (5) has two rails (51, 52) which, according to the present invention, are interposed with the two main rails (41) of the switch (4). As can be seen in the figures, a first rail (51) of the straight section of track (5) is positioned between the two main rails (41), at an approximate distance of 500 mm from one of them and about 1000 mm from the other. The other rail (52) of the straight section of track (5) is also located at a distance of about 500 mm from the first of the main rails (41) of the switch (4), but outside of it. A displacement means (3) shown in Fig. 3 moves the platform (2) transversely between the first and second positions. In this example, the displacement means (3) comprises several hydraulic cylinders connected between a pit wall in which the platform (1) is located and the frame (2). The platform (2) is moved by means of wheels (21), which are guided by rails (31) installed transversely in the same direction as the displacement cylinders. As mentioned above, in the present invention the first rail (51) of the straight track section (5), i.e., the one located between the two main rails (41), can be folded to avoid interfering with the lower clearance of the train during the track-changing process. For this purpose, an actuating means (6), in this example a hydraulic cylinder, is connected to a joint (511) of the first rail (51). Figures 2A and 2B show in detail the first rail (51) in its extended and folded positions, respectively. In the deployed position shown in Fig. 2A, the first rail (51) is in its natural vertical position to allow the train to pass over the straight section of track (5) when the frame (2) is in the second position. In this situation, the hydraulic cylinder that constitutes the actuating means (6) is retracted. In the folded position shown in Fig. 2B, the first rail (51) is in a horizontal position, which reduces its height to avoid interference during the gauge-changing process when the frame (2) is in the first position. In this situation, the hydraulic cylinder is in the extended position.

Claims

1. A mobile dual-gauge platform (1) for railway axles configured to be installed between two straight track sections, comprising: a frame (2) equipped with wheels (21) oriented transversely to the direction of travel of the train; a displacement means (3) configured to move the frame (2) transversely between a first position and a second position; a gauge changer (4) disposed on the frame (2) which, when the frame (2) is in the first position, is located between the two straight track sections, wherein said gauge changer (4) comprises: - essentially longitudinal input rails (41) at the ends of the changer with a different track gauge at each end; - guiding elements (42) on which the wagon slides when passing through the changer, supporting its weight during the wheel gauge change process.and - wheel guides (43) arranged longitudinally to force the movement of both train wheels along their own axis so that they adapt from the incoming track gauge to the new outgoing gauge regardless of the direction of entry of the train to the gauge changer; and characterized in that it further comprises a straight track section (5) arranged on the frame (2) which, when the frame (2) is in the second position, is located between the two track sections, said straight track section (5) comprising a pair of straight parallel rails (51, 52).

2. A platform (1) according to claim 1, wherein a first rail (51) of the straight track section (5) is located between the two main rails (41) of the gauge changer (4), said first rail (51) of the straight track section (5) being fixed to the frame (2) by means of a joint (511), and wherein the platform (1) further comprises a drive means (6) which, in turn,It comprises an actuator connected between the first rail (51) of the straight track section (5) and the frame (2) such that, when actuated, it causes the first rail (51) to fold or unfold, so that said first rail (51) alternates between a horizontal folded position and a vertical unfolded position.

3. Platform (1) according to claim 2, wherein the first rail (51) of the straight track section is offset with respect to the two main rails (41) of the gauge changer (4).

4. Platform (1) according to any of the preceding claims, wherein the frame (2) comprises a horizontal beam structure (22) on which the gauge changer (4) and the straight track section (5) are fixed.

5. Platform (1) according to any of the preceding claims, wherein the displacement means (3) comprises transversely oriented actuators connected between a fixed point and the frame (2).