Sliding device for railway points

Abstract: The present invention relates to a sliding device for railway points which is associated with a rail of a track in the vicinity of a set of points in which a stock rail (4) and a tongue (3) co-operate and which is provided with a support structure (7) on which at least one rotary travel element (8) able to support the tongue (3) in an inactive position (6) is mounted, and with fixing means (9) for fastening the sliding device onto the railway track. The support structure (7) is mounted on top of a slide shoe (2), with respect to which it has a matching box-shaped form having two side flanks (11) on each of which at least one spindle (16) carrying one or more rotary travel elements (8) is mounted.

Description: The present invention relates to a sliding device for railway points. The device in question is intended to be used both for the installation of new railway points and for existing points. It may also be mounted on points of any kind (single, double, intersecting, etc.) and for most of the lines provided with rail tracks which comply with the technical design standards in accordance with the characteristic features of the present invention. At present, in accordance with the known art, there exist various types of sliding devices which can be positioned inside the tracks in the vicinity of a set of points in which, as is known, a stock rail and a tongue co-operate, said stock rail being mounted by means of shoes for fixing to sleepers and said tongue being able to be displaced according to the operations performed on the points, between an active position, in which the tongue is positioned next to the stock rail, and an inactive position, in which the tongue is separated from the stock rail. The tongue has, associated with it, slide shoes which, in the absence of sliding devices, allow the tongue to be displaced between said active and inactive positions by means of sliding on a top portion thereof. Essentially the sliding devices of the known type comprise a support structure carrying one or more rotary travel elements which are able to support the tongue in a position separated from the stock rail. The support structure is generally mounted on the track by means of fixing means. Depending on the support structure, rotary travel elements and fixing means used, various constructional solutions and therefore different types of sliding devices may be configured. A first type of device is directly formed on the slide plate of the tongue or in any case requires a special design of the slide plate, as emerges for example from the description of the patents DE 4041264 and US 5390881. This known type of device has the disadvantage that it can be mounted exclusively on a plate specially designed to receive it. In fact, it cannot be mounted on the most common design of slide plates which is used nowadays for example on railway lines. This means that this type of device may be mounted only during construction of a set of points, while it cannot be installed in ready existing points unless the slide plate already mounted is completely replaced or complex modifications are made to adapt the slide plate, which modifications, however, are not always possible. Another known type of sliding device involves the use of a support structure mounted on the tracks by means of fixing means which are connected in cantilever fashion to the sleepers or connected between two consecutive sleepers. In this connection, see, for example, the descriptions of the patents US 5509626, DE 1658366 and AT 375697. This type of device, unlike the preceding one, may be mounted on any type of points, including those already installed, since the means for fixing the support structure of the rotary travel elements relate mainly to the sleepers and therefore elements which generally have standard technical design features. The main defect of this type of device consists in the fact that it is not easy enough to install and sometimes requires the introduction of minor modifications in order to allow connection of the fixing means which must be able to relieve the stresses of the rotary travel elements which are not arranged directly above the sleepers. In a further known type of sliding device, fastening to the track is performed directly on the flange of the rail by means of fixing means which require the introduction of a plurality of elements (for example securing clamps shaped so as to match the flange of the stock rail) which involve increases in the production and installation costs (see description of patent CH 368201). Finally it should be remembered that, for all the types of devices mentioned hitherto, it is often necessary to make minor modifications to the tracks which in most cases must be submitted for approval to the competent bodies. The main object of the present invention is therefore that of overcoming the drawbacks associated with the devices of the known type by providing a new sliding device which can be installed rapidly and on any type of points without requiring the modification of any of the track's characteristics. A further object of the present invention is that of providing a sliding device which is constructionally simple and operationally entirely reliable and which requires little maintenance and can be rapidly and simply installed. These objects, together with others, are all achieved by a sliding device as defined in claim 1. The sliding device according to the present invention essentially comprises a support structure on which one or more rotary travel elements designed to support a tongue in an inactive position and fixing means for fastening the sliding device on the railway track are mounted. The support structure is mounted on top of a slide shoe and has a box-shaped form matching that of a top portion of the slide shoe itself. The support structure also has two side flanks on each of which a spindle carrying one or more rotary travel elements is mounted. The technical features of the invention, in accordance with the aforementioned objects, may be clearly understood from the contents of the claims indicated below and the advantages thereof will emerge more clearly from the detailed description which follows, provided with reference to the accompanying drawings which illustrate a purely exemplary non-limiting example of embodiment thereof, in which: Figures 1, 2 and 3 show an exploded view, top view and cross-sectional view (along the line III-III of Fig. 2), of a first embodiment of the sliding device according to the present invention with some parts removed so that others may be more clearly seen; Figures 1a, 2a and 3a show an exploded view, top view and cross-sectional view (along the line III-III of Fig. 2a) of a constructional variant of the first embodiment of the sliding device according to Figs. 1, 2 and 3; Figures 4, 5 and 6 show an exploded view, top view and cross-sectional view (along the line VI-VI of Fig. 5), of a second embodiment of the sliding device according to the present invention; Figures 7, 8 and 9 show an axonometric view, top view and cross-sectional view (along the line IX-IX of Fig. 8) of a further embodiment of the invention; Figures 10a, 10b and 10c show, respectively, an exploded view, a front view and a plan view of a first example of embodiment of the means for fixing the device in question; Figure 11a shows an exploded view of a second example of embodiment of the means for fixing the device in question; Figure 11b shows a side view of the constructional detail of Fig. 11a with some parts removed so that others may be seen more clearly. The sliding device according to the present invention, denoted by 1, is particularly suitable for use in the sector of railway points and may be applied to slide shoes 2 which, in the jargon of the person skilled in the art, are commonly referred to as "slide plates" . As is known, railway points are composed essentially of tongues 3 which are arranged inside stock rails 4 and connected to one another by tie-rods (not shown). By means of manual or automatic operation, the tongues 3 together with a support frame connected to them are displaced so that each tongue 3 rotates about its heel (i.e. the end opposite to the toe). In other words, each tongue 3 is able to be displaced, depending on the operations performed on the points, between an active position 5, where it is positioned next to the stock rail 4, and an inactive position 6, where it is separated from the stock rail 4. As can be seen in particular from the exploded views of Figures 1, 1a, 4 and in Figure 7, the sliding device 1 comprises essentially a support structure 7 on which rotary travel elements 8 capable of supporting the tongue 3 in the said inactive position 6 are provided. The support structure 7 has, associated with it, fixing means 9 for mounting the sliding device 1 on top of the slide plate 2. For this purpose, considering the standard substantially parallelepiped form of the slide plate 2, the support structure 7 has a box-shaped form substantially matching that of a top portion 10 of the said slide plate 2. The box-shaped form is obtained by means of two side flanks 11 and by means of a flat, substantially horizontal element 12 forming at the top a connection between the abovementioned side flanks 11 along an upper edge 13 thereof. Each side flank 11 has, moreover, an extended portion 14 forming a single body therewith and extending beyond an external transverse edge 50 of the flat element 12 until it engages underneath the tongue 3. With reference in particular to Figures 2 and 2a, the external transverse edge 50 corresponds to the edge of the flat element 12 directed towards the tongue 3. Each of the two side flanks 11 of the support structure 7 shown in Fig. 2 has mounted, projecting from it, respectively two spindles 16 each carrying a rotary travel element 8 advantageously consisting of directable sealed ball bearings which are able to adapt to the small differences in arrangement of the flange of the tongue 3 which occur following displacement of the latter between said active position 5 and said inactive position 6. Figures 1a, 2a and 3a show a constructional variant of the first embodiment of the sliding device shown in Figures 1, 2 and 3. In this variant, mounting of a single travel element on the side flanks 11 of the support structure has been envisaged. Advantageously it will therefore be possible to use sliding devices having a different number of travel elements depending on the width of the flange of the tongue. For example it is possible to envisage the installation of a device with two travel elements per side of the support structure at the toe of the tongue and only one at the heel of the tongue. The ball bearings are slightly raised with respect to the flat element 12 and in this way are able to receive, above them, the flange of the tongue 3 when the latter passes from the active position 5 to the inactive position 6. The standard slide plates 2, to which reference is made in the accompanying drawings, have engaging elements 17 which are able to co-operate in a mutually connected relationship with the fixing means 9. The latter may have different constructional forms and advantageously are preferably arranged on a side flank 11 of the support structure 7 opposite a cavity (which in this case performs precisely the function of engaging means 17) present on a side face 18 of the slide plates 2. In accordance with a first example of embodiment (shown in Figures 1, 2, 3, 1a, 2a, 3a, 10a, 10b and 10c), the fixing means 9 consist of a connecting plate 19 mounted on the support structure by means of a first screw 20 passing through a first opening 21 formed on a side surface 11. The connecting plate 19 has, mounted on it, two first bolts 22 formed by a first nut 23 and by a second screw 24 with an eccentric cam on the end. From a functional point of view, the two first bolts 22 are operationally movable between an insertion position 26 (see Fig. 10c) where they may be inserted without interference with the eccentric head 25 inside the abovementioned cavity 17, and a locked gripping position 27 (see Figs. 2 and 2a), where the eccentric heads 25 act sealingly inside the cavity 17 in an opposing manner, thus locking the entire sliding device 1 to the slide plate 2. In Figure 3 it can be seen that adjustment of the position of the support structure 7 is ensured by the presence of the first opening 21 consisting of a first eyelet extending in a direction X substantially transverse to the rails. Owing to this eyelet the first screw 20 may lock in different positions the support structure 7 on the slide plate 2 in the abovementioned direction X. In accordance with a second example of embodiment (shown in Figures 11a and 11b) the fixing means 9 consist of two fastening elements 28, 29 which are operationally combined so as to slide mutually on one another along a common inclined plane P. The relative sliding of the two fastening elements 28, 29 results in the formation of a first wide configuration 30, in which the two fastening elements 28, 29 act sealingly inside the cavity 17 by means of two corresponding gripping surfaces 32, 33, and a second configuration 31, close to one another, in which the two fastening elements 28, 29 may be inserted without interference inside the cavity 17 itself. The adjustment of sliding between the two fastening elements 28, 29 is made possible by a third screw 34 which is operationally combined with a female thread formed on one of the two fastening elements 28, 29 and passing through a second opening formed on the side flank 11 of the support structure 7 in the region of the cavity 17. Advantageously the second opening also consists of a second eyelet elongated in a direction X substantially transverse to the rails and designed to allow adjustment of the position of said third screw 34 on the side flank 11, and hence of the support structure 7, with respect to the slide plate 2. In accordance with a third example of embodiment (shown in Figures 11a and 11b), the fixing means 9 substantially consist of a third opening 37 formed at the top of the support structure 7 and passed through by an element 38 for fixing the slide plate to a sleeper 40. In this case also (see Figs. 4 and 7) the third opening 37 consists of a third eyelet elongated in a direction X" substantially transverse to the rails and designed to allow adjustment of the position of the support structure 7 with respect to the slide plate 2. To ensure greater ease of assembly of the sliding device in question, the said third eyelet is open along an internal transverse edge 39 of the flat element 12. With reference to Figures 4 and 7, the internal transverse edge 39 corresponds to the edge of the flat element 12 directed towards the inside of the track. In all the examples of embodiment described, assembly of the sliding device by means of the action of the fixing means 9 on the slide plates 2 is performed without the need for any modification of elements present in the points. The sliding device 1 in question may envisage moreover the use of a protection frame 41 mounted so as to protect the rotary travel elements 8 on each side flank 11 of the support structure. The connection of the protection frame to the support structure 7 is achieved by means of screws 42 which engage in the ends of the spindles 16. Functionally speaking, in accordance with the present invention, the tongue 3 must be able to be displaced depending on the operations performed on the points, between the (active) position 5, where it is next to the stock rail 4, and the (inactive) position 6, where it is separated from the stock rail 4, in an extremely simple manner, being assisted in this connection by the sealed ball bearings. This requires that, depending on the particular type of points (and hence also the different types of tongues 3) a different number of sliding devices must be installed in positions which may also vary along the length of the tongue 3. Moreover, in view of the particular form of the tongue 3, i.e. with a flange which is wider towards the heel and narrower towards the toe, it may be necessary to provide, at the toe, sliding devices which have several rows of ball bearings (in the examples shown reference has always been made to two rows of ball bearings), while it may be sufficient to arrange a single row of ball bearings in the heel. Finally (see Figs. 7, 8 and 9) it should be noted that, in addition to reinforcing the side flanks 11 of the support structure 7, it is possible to provide a reinforcing frame 43 fixed onto the side flanks 11 themselves, capable of co-operating with the latter so as to support the rotary travel elements, relieving them of the forces transmitted to them by the tongue 3.

Claims: Sliding device for railway points, of the type associated with a rail of a track in the vicinity of a set of points in which at least one stock rail (4) and at least one tongue (3) co-operate, said tongue being able to be displaced depending on the operations performed on the points, between an active position (5), in which it is next to the stock rail (4), and an inactive position (6), in which it is separated from the stock rail (4), said sliding device (1) comprising a support structure (7) on which at least one rotary travel element (8) designed to support said tongue (3) in said inactive position (6) is mounted, said support structure (7) being associated with fixing means (9) for fastening said sliding device (1) onto the railway track, characterized in that said support structure (7) is mounted, by means of the action of said fixing means (9), on top of a slide shoe (2) mounted on top ot a sleeper (4C), without requiring any modification of the elements which form the points, which support structure has a box-shaped form substantially matching that of a top portion (10) of said slide shoe (2), said support structure being provided with two side flanks (11), on each of which at least one spindle (16) carrying at least one of said rotary travel elements (8) is mounted. Device according to Claim 1, characterized in that said fixing means (9) co-operate in a mutually connected relationship with engaging elements (17) present on said said slide shoe (2). Device according to Claim 1, characterized in that said fixing means (9) are installed on at least one side flank (11) of said support structure (7) opposite at least one cavity (17) present on a side surface of said slide shoe (2). Device according to Claim 3, characterized in that said fixing means (9) substantially consist of a connecting plate (19) mounted on said support structure by means of a first screw (20) passing through a first opening (21) formed on said side flank (11), at least one first bolt mounted on said connecting plate (19) and composed of a first nut (23) and a second screw (23) with an eccentric cam (25) at the end, said first bolt being operationally movable between a locked gripping position (27), where said eccentric cam (25) acts sealingly inside said cavity (17), and an insertion position (26), where said eccentric cam (25) may be inserted without interference inside said cavity (17). Device according to Claim 4, characterized in that it comprises two said first bolts (22) which are mounted on said connecting plate (19) in two opposite peripheral positions and which act sealingly by means of said eccentric cams (25) inside said cavity (17) in an opposing manner in said locked gripping position (27). Device according to Claim 5, characterized in that said first opening (21) consists of a first eyelet elongated in a direction (X) substantially transverse to the rails and designed to allow adjustment of the position of said support structure (7) by means of said first screw (20) on the side face (18) of said slide shoe (2). Device according to Claim 3, characterized in that said fixing means substantially consist of at least two fastening elements (28, 29) which are operationally combined so as to slide mutually on one another along a common inclined plane (P), at least a third screw (34) passing through a second opening formed on said side surface (11) and engaging with a female thread formed on one of said fastening elements (28, 29), said two fastening elements (28, 29) being designed to form a first wide configuration (30), in which they sealingly act inside said cavity (17) by means of two corresponding gripping surfaces (32, 33), and a second configuration (31), close to one another, in which they may be inserted without interference inside said cavity (17). Device according to Claim 7, characterized in that said second opening consists of a second eyelet elongated in a direction (X) substantially transverse to the rails and designed to allow adjustment of the position of said support structure (7) by means of said third screw (34) on the side face (18) of said slide shoe (2). Device according to Claim 1, characterized in that said box-shaped form is obtained by means of said two side flanks (11) extending on two separate parallel flat planes and connected together along their top side edge by a flat, substantially horizontal element (12), each of said side flanks (11) having an extended portion (14) extending underneath said tongue (3) beyond an external transverse edge (50) of said flat element (12) directed towards said tongue (3). Device according to Claim 3, characterized in that said fixing means (9) substantially consist of a third opening (37) formed at the top of said support structure (7) and passed through by an element (38) for fixing the slide shoe (2) to a sleeper (40). Device according to Claim 10, characterized in that said third opening (37) consists of a third eyelet elongated in a direction (X") substantially transverse to the rails and designed to allow adjustment of the position of said support structure (7) with respect to said slide shoe (2). Device according to Claim 11, characterized in that said third eyelet is open along an internal transverse edge (39) of said flat element (12) directed towards the inside of the track. Device according to Claim 1, characterized in that it comprises a protection frame mounted on each of said side flanks (11) and designed to embrace said rotary travel elements (8) so as to protect them from damage. Device according to Claims 1 and 13, characterized in that said protection frame is mounted on said side flanks (11) by means of screws (42) engaging on the ends of said spindles (16). Device according to Claim 1, characterized in that it comprises a reinforcing frame mounted on each of said side flanks (11) and designed to co-operate with the latter so as to support said rotary travel elements (8), relieving them of the forces transmitted to them by said tongue (3). Device according to Claim 1, characterized in that said spindles (16) are fixed, projecting, on said side flanks (11) on the outside of said support structure (7). Device according to Claim 1, characterized in that said spindles (16) are two in number for each side flank (11), each said spindle carrying one said rotary travel element (8). Device according to Claim 1, characterized in that said spindles (16) are one in number for each said side flank (11), each said spindle carrying one said rotary travel element (8). Device according to Claim 1, characterized in that said rotary travel elements (8) consist of directable sealed ball bearings able to adapt to the small different arrangements of the flange of the tongue (3) which occur following the displacements of the latter between said active position (5) and said passive position (6).

Inventors: MAZZI GRAZIADIO, MAZZI, GRAZIADIO
Applicants: IMPRESA ANGELO MAZZI S N C DI, IMPRESA ANGELO MAZZI S.N.C., DI MAZZI ALDO E GRAZIADIO
Application year: 1998
Main classification: E01B7
IPC codes: E01B7