IL296460B2 - Assembly for switches and crossings - Google Patents

Description

WO 2021/185768 1 PCT/EP2021/056544 Title of the invention: Assembly for switches and crossings id="p-1" id="p-1"

[001] The present invention relates to the field of switches and crossings for vehicles of tramway type and, more particularly, to the field of these switches and crossings incorporating a maintenance management mechanism. id="p-2" id="p-2"

[002] Like the rails, the switches and crossings are also subject to regular stresses generated by the running of the vehicles or originating from heat variations or aggression from the environment which lead to wear of some of the surfaces of the switches and crossings. Moreover, since the switches and crossings are strategically positioned along railway lines to change the direction of the vehicles or at railway crossings, some particular portions of these switches and crossings are then subject to impacts with wheels of the vehicles with greater frequency than a simple rail. Subjected to repeated wear, the switches and crossings, and in particular the rolling surfaces of the switching or crossing which act as stock rails, then demand regular monitoring and maintenance of their structures likely to culminate in the repair or even replacement thereof. id="p-3" id="p-3"

[003] In the context of the repair of the structure of a switching or crossing forming a stock rail, this is performed on site and demands a shutdown of the use of the portion of track including the switch or crossing. This repair essentially consists in operations involving resurfacing with a suitable filamental of the zone of the switch or crossing where the stock rail function is applied, followed by an operation of grinding of the same zone that can lead to any movement of vehicles on a portion of track being blocked for a time. When the repairs to be made in this particular zone are too great, an alternative to this repair on site consists in proceeding to replace all of the structure providing the stock rail function. In this particular case, operations involving dismantling the portion of switch or crossing to be replaced followed by the installation of new replacement elements cause major works WO 2021/185768 2 PCT/EP2021/056544 to be undertaken for the implementation of this solution to address the problem of degradation of the structure of the element which forms the stock rail of the switch or crossing. Moreover, this type of intervention is then likely to be complicated when a part of the switch or crossing is incorporated in the ground by a coating or a concrete. id="p-4" id="p-4"

[004] The aim of the present invention is to mitigate these drawbacks of the prior art by proposing a switch or crossing which allows easier maintenance and rapid intervention to carry out the repair or even replacement of particular rolling surfaces of switches and crossings subject to wear. id="p-5" id="p-5"

[005] Thus, the subject of the invention is an assembly for switches and crossings defining a direct track and a diverted track comprising:- a single-piece structure,- a switch point rail movably mounted on the single-piece structure, characterized in that the assembly comprises at least one block forming the stock rail, the block being removably mounted on a dedicated part of the single-piece structure. id="p-6" id="p-6"

[006] Another subject of the invention is a switch or crossing of switch type which incorporates an assembly according to the invention. id="p-7" id="p-7"

[007] The invention will be better understood, from the following description, which relates to the preferred embodiments, given as nonlimiting example, and explained with reference to the attached schematic drawings, in which: id="p-8" id="p-8"

[008] [Fig. 1] is a schematic representation by an exploded view of an example of an assembly according to the invention. id="p-9" id="p-9"

[009] [Fig. 2] is a schematic representation of an example of a half-switch by a view from the direct and diverted tracks incorporating an assembly according to the invention. id="p-10" id="p-10"

[0010] [Fig. 3] is a schematic representation of a sectional view at a point of contact of the switch point rail with the block forming the stock rail according to an example of an assembly according to the invention.

WO 2021/185768 3 PCT/EP2021/056544 id="p-11" id="p-11"

[0011] [Fig. 4] is a schematic representation of a sectional view at a fixed end of the movable switch point rail in an example of an assembly according to the invention. id="p-12" id="p-12"

[0012] [Fig. 5] is a schematic representation of a sectional view at a point of contact of the switch point rail with the block forming the stock rail according to an alternative example of an assembly according to the invention. id="p-13" id="p-13"

[0013] [Fig. 6] is a schematic representation of a top view detailing a particular construction of a block forming the stock rail and of its receptacle according to an example of an assembly according to the invention. id="p-14" id="p-14"

[0014] [Fig. 7] is a schematic representation of a top view of an exampleof a switch or crossing incorporating two assemblies according to the invention. id="p-15" id="p-15"

[0015] The present invention relates to an assembly for switches andcrossings 10 defining a direct track A and a diverted track B comprising: - a single-piece structure 2,- a switch point rail 3 movably mounted on the single-piece structure 2, characterized in that the assembly comprises at least one block 4 forming the stock rail, the block 4 being removably mounted on a dedicated part of the single-piece structure 2. This particular construction in which the block forming the stock rail is removable with respect to a single-piece structure which also constitutes a support base on which a switch point rail 3 of the switch or crossing 10 is movable, makes it possible to optimize the on-site intervention time by dispensing with dismantling of all of the structure of the half-switch of the switch or crossing 10 to restrict it to just the block 4 forming the stock rail to be removed. By being mounted on the single-piece structure 2, the block 4 forming the stock rail has the advantage of being accessible from the top for an operative wanting to separate the element constituting the stock rail from its support formed by the single-piece structure 2. Also, according to an exemplary embodiment, the single-piece structure 2 has an WO 2021/185768 4 PCT/EP2021/056544 arrangement configured to access, by the top face of the single-piece structure 2, the block 4 forming the stock rail so as to separate the block forming the stock rail from its support formed by the single-piece structure 2. This access to the block 4 forming the stock rail from the top side of the single-piece structure 2 allows direct access to the stock rail and to the elements fixing the block 4 forming the stock rail onto the single-piece structure 2. Such access to the block 4 forming the stock rail and to the fixing elements thus allows detachment and removal of the block 4 forming the stock rail from its support formed by the single-piece structure 2 without it being necessary to access the other lateral and bottom faces of the single­ piece structure 2, such that the removal of the block 4 forming the stock rail can be performed without an operation involving dismantling or removing the single-piece structure 2. In addition, the switch point rail 3 also movably mounted on the single-piece structure 2 is configured to abut by one of its lateral faces against the block 4 forming the stock rail such that the switch point rail 3 is not superimposed on top of the block 4 forming the stock rail and does not interfere in the access to this block 4 for an operative. Also, access to the block 4 forming the stock rail is not prevented by the switch point rail 3. id="p-16" id="p-16"

[0016] According to an exemplary embodiment of the assembly of the invention, the stock rail function is performed by at least two blocks 4 that are juxtaposed in the extension of one another and mounted on the same single-piece structure 2 so as to create at least a continuity of rolling surfaces borne successively by the different blocks 4. According to a preferred particular construction feature of the single-piece structure, the different blocks 4 which follow one another also have a continuity on the surfaces of the different successive blocks 4 intended to be in contact with the switch point rail 3 of the switch or crossing. id="p-17" id="p-17"

[0017] According to an exemplary embodiment of the assembly of the invention, the single-piece structure 2 comprises a receptacle 5 of a form WO 2021/185768 5 PCT/EP2021/056544 complementing the block 4 forming the stock rail, configured to allow the positioning therein of the block 4 by insertion. It should be noted that the single-piece structure 2 which incorporates a receptacle 5 intended to receive a removable block 4 forming the stock rail comprises, upstream and downstream of the receptacle 5, rolling surfaces intended to interact with the wheels of a moving vehicle. Moreover, this single-piece structure 2 illustrated and called "single-piece" can be produced in the form of an element of structurally unitary material or, alternatively, in the form of multiple parts assembled together, even welded together, while not departing from the scope of the invention claimed. According to a particular feature, when the stock rail function is fulfilled by multiple blocks 4, the different blocks 4 are adapted to share the same receptacle 5. id="p-18" id="p-18"

[0018] According to a particular construction of this receptacle 5, the latter is produced in the single-piece structure 2 so as to have at least opening at the top and toward the switch point rail 3 mounted on the single-piece structure 2. Such a construction of the receptacle 5 thus makes it possible to apply the positioning therein of a block 4 forming the stock rail which comprises, on the one hand, a first surface which forms a rolling surface accessible from the top for coming into contact with a wheel of a rail car and, on the other hand, a second surface which forms a contact surface for the flange of a car wheel or an abutment for a surface of the switch point rail bearing against the block 4 forming the stock rail. According to one implementation of this particular example, the single-piece structure comprises, on the one hand, a base 2a on which the movably mounted switch point rail 3 rests, directly or indirectly, and, on the other hand, a portion 2b positioned laterally to the base 2a and which extends above the latter. According to a preferred arrangement, the surface of the lateral portion 2b of the single-piece structure 2 which is positioned above the top surface of the base 2a is disposed so as to face the abutment surface of the movable switch point rail 3 on the single-piece structure 2. The receptacle 5 is thus produced in such a way as to comprise at least a surface of the lateral portion WO 2021/185768 6 PCT/EP2021/056544 2b of the single-piece structure 2 and a surface of the base 2a, such that these two surfaces 2a, 2b produce between them a concavity configured and intended to receive the removable block 4 forming the stock rail. According to a preferred implementation of the construction of this receptacle 5, the lateral portion 2b and the base 2a are disposed such that the insertion of the block 4 forming the stock rail in the receptacle 5 can be performed with a translation applied by a substantially vertical movement and/or by a substantially horizontal movement. id="p-19" id="p-19"

[0019] According to a specific production feature of the particular examplepreviously described of the assembly of the invention, the assembly comprises at least one device for vertically and/or horizontally retaining the block 4 forming the stock rail positioned in the receptacle 5. This device incorporated in the assembly of the invention, according to its construction, thus ensures, fully or partially, holding of the block 4 forming the stock rail in position in the dedicated receptacle 5 of the single-piece structure 2. This holding thus prevents the block 4 forming the stock rail from becoming detached from the single-piece structure 2 along at least one axis of movement. id="p-20" id="p-20"

[0020] According to a first exemplary implementation of this retainingdevice, the latter is produced in such a way that the single-piece structure comprises a relief 6 disposed on a surface of the receptacle 5 and intended to interact with a surface of the block 4 forming the stock rail. Depending on the surface of the receptacle 5 which bears this relief 6 and which interacts with the block 4 forming the stock rail, the block 4 movement locking axis can differ. Also, the relief 6 is disposed so as to cooperate with a part of the block 4 forming the stock rail to oppose a movement in at least a vertical or horizontal plane. This relief 6 can take the form of a dock point or of an axial structure arranged to cooperate with a substantially complementary form borne by the block 4 forming the stock rail.

WO 2021/185768 7 PCT/EP2021/056544 id="p-21" id="p-21"

[0021] According to another exemplary embodiment that can be combined with the first example, the retaining device involves a relief positioned at the border of a surface of the receptacle 5. Thus, the retaining device positioned on a top edge of the receptacle 5 of the single-piece structure 2 comprises a locking lip 6 for locking the vertical translation of a block 4 forming the stock rail positioned in the receptacle 5. This lip 6 thus forms an extension beyond the top edge of the lateral portion 2b of the single-piece structure 2 so as to be positioned above the top surface of the base 2a. Also, the space separating the bottom face of the lip 6 and the top face of the base 2a defines a part of the volume of the receptacle 5 for the insertion of the block 4 forming the stock rail. The distance which separates the bottom face of the lip 6 and the top face of the base 2a corresponds substantially to the height of the block 4 forming the stock rail in its insertion portion. According to a particular implementation of this lip 6 in the assembly of the invention, this lip 6 is disposed on the entire length of the top edge of the lateral portion 2b of the single-piece structure 2, such that any vertical movement of the block 4 forming the stock rail inserted into the receptacle of the single-piece structure 2 is prevented. However, according to an alternative to this particular implementation, the lip 6 is produced discontinuously at at least two spaced-apart points of the top edge of the lateral portion 2b of the single-piece structure 2. According to an alternative implementation, a locking lip is positioned at the periphery of the base 2a to oppose a horizontal translation of the block 4 forming the stock rail with respect to the receptacle 5. id="p-22" id="p-22"

[0022] According to another exemplary embodiment that can becombined with at least one of the other two examples previously described, the retaining device involves a fixing piece, such as a lag screw or a screw, which keeps the block 4 forming the stock rail assembled with the single­piece structure by passing through at least one of these two elements.

According to a first variant of this example, the single-piece structure 2 is passed right through in a dedicated bore by the fixing piece to cooperate WO 2021/185768 8 PCT/EP2021/056544 with a tapped bore of the block 4 forming the stock rail. According to an alternative variant of this example, the fixing piece passes right through the stock rail 4 in a dedicated bore to cooperate with a tapped bore of the single­piece structure 2. According to another variant of this example, the fixing piece passes right through the block 4 forming the stock rail and the single­piece structure 2 such that the block 4 and the single-piece structure 2 are pincered between the head of the fixing piece and an associated piece such as a bolt. id="p-23" id="p-23"

[0023] According to another exemplary embodiment that can becombined with at least one of the other three examples previously described, the retaining device involves a particular construction of the complementary nature of the block 4 forming the stock rail with the single-piece structure 2. Thus, in a substantially horizontal plane, at least a first end of the block forming the stock rail has a construction of pointed convex form arranged to cooperate with an end of concave complementary form 2d of the receptacle borne by the single-piece structure 2. According to a preferential implementation of this particular example, the concavity 2d of the end of the receptacle 5 is produced to be borne by the lateral portion 2b of the single­piece structure 2 which extends heightwise above the top surface of the base 2a of this single-piece structure 2. According to another complementary preferential implementation of this particular example, the concavity 2d of the receptacle 5 is arranged to surround the end of the block 4 forming the stock rail on a number of its faces. Thus, the concave end of the receptacle interacts with the point of the block 4 forming the stock rail, on the one hand, at the end of its point and, on the other hand, on each of the lateral faces of the end of the block 4 forming the stock rail or of a component of these lateral faces of the end. According to a construction preference, the part of the point positioned at the end of the lateral face of the block intended to face the switch point rail 3 makes an angle with the lateral face of between 0° and 90°, preferentially between 35° and 60°, ideally of the order of 45°, to present the form of a chamfer in a horizontal plane. This WO 2021/185768 9 PCT/EP2021/056544 convex arrangement of the end of the block 4 forming the stock rail allows, on the one hand, an insertion of the block 4 into the receptacle 5 which is made easier when it is performed at this first end prior to the positioning of the rest of the body of the block 4 forming the stock rail in the receptacle and, on the other hand, a locking of the inserted block 4 in a different direction from the horizontal plane. id="p-24" id="p-24"

[0024] According to an example complementary to this particularexemplary implementation of a concavity 2d at the end of the receptacle intended to receive the first end of the block 4 forming the stock rail, the second end of the block 4 has a construction forming a chamfer or a bevel in a horizontal plane and intended to cooperate with a complementary arrangement 2e formed, at the end of the receptacle 5, by a dedicated surface of the lateral portion 2b of the single-piece structure 2. According to a construction preference, the angle of the bevel with the lateral face of the block 4 is between 0° and 90°, preferentially between 35° and 60°, ideally of the order 45°. This arrangement then allows the dedicated surface 2e of the single-piece structure 2 to fulfil the function of slip ramp, which, by reaction, translates the block 4 forming the stock rail toward the concave end of the receptacle 5 when the beveled second end of the block 4 is pressed, in a horizontal plane, against the dedicated surface of the receptacle 5. One advantage of the production of a block 4 forming the stock rail in which the ends have different arrangements that respectively complement the receptacle 5 borne by the single-piece structure 2 is to impose a single direction of insertion of the block 4 forming the stock rail into its receptacle and consequently avoid an incorrect assembly of the assembly according to the invention. id="p-25" id="p-25"

[0025] According to another exemplary embodiment that can be combined with the other four examples previously described, the retaining device involves a locking piece 7 configured to be fixed directly or indirectly to the single-piece structure 2 and comprising at least one bearing surface WO 2021/185768 10 PCT/EP2021/056544 7a intended to interact with a surface of the block 4 forming the stock rail so as to press the block 4 against the single-piece structure 2. The locking piece comprises an interface 7b for fixing onto the single-piece structure 2, for example on the top surface of the base 2a. According to a nonlimiting preferential implementation of the invention, the locking piece 7 is arranged such that the fixing interface 7b cooperates with the top surface of the base 2a of the single-piece structure 2. According to one example, the fixing of the locking piece 7 involves a piece, such as a lag screw or a screw, which passes right through the locking piece 7 in a dedicated bore from a part of the top surface of the locking piece 7 to cooperate with a tapped bore of the single-piece structure 2. This insertion of the fixing piece on the top surface of the locking piece 7 allows easier access for the user or operative on site when the locking piece 7 has to be detached from the single-piece structure 2 to release the block 4 forming the stock rail from the receptacle 5 of the single-piece structure 2. Moreover, the locking piece 7 is arranged to be mounted and fixed onto the single-piece structure 2 such that the top surface of this single-piece part does not affect the movement of a vehicle wheel on the rolling surface of the block 4 and notably the peripheral edge of the flange of a wheel moving along a lateral face of the block 4 forming the stock rail. To this end, and according to a preferred arrangement, the locking piece is positioned bearing against a surface of the block 4 forming the stock rail at a distance from the rolling surface of the block 4, such that the distance between the rolling surface of the block 4 and the top surface of the locking piece 7 is greater than the height of the flange of a rail vehicle wheel intended to move over a switch or crossing 10 incorporating an assembly according to the invention. id="p-26" id="p-26"

[0026] According to a specific production feature of this particular example, the locking piece 7 is configured to prevent the translation of the block forming the stock rail along at least one horizontal axis. According to a preferred arrangement of this specific production feature, the bearing surface 7a of the locking piece 7 is configured to face the lateral portion 2b WO 2021/185768 11 PCT/EP2021/056544 of the single-piece structure 2. This arrangement allows the pincering, even the clamping, of the block 4 forming the stock rail in a substantially horizontal plane between, on the one hand, the bearing surface 7a of the locking piece and, on the other hand, a surface of the receptacle 5 formed by the lateral portion 2b of the single-piece structure 2. According to an additional specific implementation feature proposed by way of example, the single-piece structure 2 comprises an additional portion 2c configured to form an abutment for the locking piece 7 in horizontal plane on a bearing surface 7c, such that the locking piece 7 and the block 4 forming the stock rail are positioned between two portions of the single-piece structure 2 that are, on the one hand, the lateral portion 2b and, on the other hand, the additional portion 2c. id="p-27" id="p-27"

[0027] According to an additional exemplary specific production feature of the locking piece 7, this piece 7 comprises, on its bearing surface 7a intended to interact with the block 4 forming the stock rail, a slope such that the bearing surface 7a forms a ramp, the lead of which at the top level is greater than the lead at the bottom level. This ramp of the bearing surface 7a is configured to interact with a complementary surface of the block forming the stock rail such that the vertical forces of movement of the stock rail 4 generate a horizontal component on the blocking piece 7. Thus, the block 4 forming the stock rail is also locked in vertical translation by the locking piece 7 by the production of this bearing surface 7a in the form of a ramp 4 or an inclined surface. id="p-28" id="p-28"

[0028] According to another particular exemplary embodiment of the assembly of the invention complementing the examples previously detailed, the locking piece 7 is configured to interact at at least one of the ends of the block 4 forming the stock rail. In combination with the implementation of a concavity at the end of the receptacle 5 intended to receive the first end of the block 4 forming the stock rail, the locking piece 7 is preferentially positioned at the second end of the receptacle 5 such that, in a horizontal WO 2021/185768 12 PCT/EP2021/056544 plane, the block 4 forming the stock rail is held in position in the receptacle of the single-piece structure 2 by virtue of a two-point locking of the block 4, namely, on the one hand, in the concave/convex interaction of the receptacle 5 and, on the other hand, on the locking piece 7. id="p-29" id="p-29"

[0029] According to another particular exemplary embodiment of theassembly of the invention complementing the examples previously detailed, at least one surface of the block 4 forming the stock rail intended to bear against the single-piece structure 2 comprises at least one receptacle configured to incorporate a heating element 9. According to a preferred implementation, this receptacle 8 is produced in the form of a bore in the thickness of the block 4 forming the stock rail which comprises an orifice on the surface of the block 4 intended to be in contact against the single-piece structure 2. Preferentially, the orifice of this receptacle 8 is borne by the surface intended to interact with a surface of the lateral portion 2b of the single-piece structure 2. However, the position of this receptacle 8 in the thickness of the block 4 forming the stock rail can be adapted according to the position and the specific bulk of the heating element 9. id="p-30" id="p-30"

[0030] According to another particular exemplary embodiment of theassembly of the invention complementing the examples previously detailed, the block 4 forming the stock rail is produced from a steel of higher strength than the steel of the single-piece structure 2. Thus, the assembly of the invention comprising a block 4 forming the stock rail that is structurally independent of the single-piece structure 2 which bears it allows the construction material to be adapted to the function of the piece or of the particular element forming part of the assembly of the invention. This adaptation, on the one hand, allows a combination of different materials with specific properties and, on the other hand, makes it possible to limit the use of materials with higher production costs to just the elements where they are necessary, even essential. Thus, the block 4 forming the stock rail which has to withstand, notably on its rolling surface, greater forces because it is WO 2021/185768 13 PCT/EP2021/056544 repeatedly run over by vehicle wheels, is produced in a material better suited to such stresses, for example a high strength steel or alloy or one offering enhanced ease of welding, than the single-piece structure 2 forming the support structure of the assembly of the invention produced in a less noble steel such as, for example, S355 JO. id="p-31" id="p-31"

[0031] The invention relates also to a switch or crossing 10 of switch type which incorporates at least one assembly according to the invention. Preferentially, the switch or crossing 10 incorporates an assembly on each of the rail lines of a railway branch. This assembly according to the invention is thus incorporated in a switch or crossing 10 to form a half-switch 1. Thus, the assembly of the invention is duplicated in the context of a switch or crossing 10 according to the invention. An example of a switch or crossing according to the invention is notably schematically illustrated by figure 7. id="p-32" id="p-32"

[0032] In the context of the replacement of a block 4 forming the stock railin an assembly of a switch or crossing 10 according to the invention, the operative applies:- a movement of the switch point rail 3 with respect to the block 4 so as to separate these two elements,- a removal of the locking piece 7 from the single-piece structure 2 on which it is mounted, - a removal of the block 4 forming the stock rail from the receptacle 5 of the single-piece structure 2, - an insertion of a new replacement block 4 forming the stock rail into the receptacle 5 of the single-piece structure 2, - a locking of the replacement block 4 in the receptacle 5 by positioning of the locking piece 7 against the block 4 and the fixing thereof to the single-piece structure 2. id="p-33" id="p-33"

[0033] When the assembly according to the invention incorporatesheating elements, the operative proceeds, on the one hand, with the removal of the heating elements prior to the step of movement of the switch point rail WO 2021/185768 14 PCT/EP2021/056544 3 and, on the other hand, with the replacement of these heating elements at the end of the method. id="p-34" id="p-34"

[0034] More particularly, the insertion of the block 4 forming the stock railinto the receptacle 5 of the single-piece structure 2 is performed by inserting and then chocking the first end which forms the point of the block 4 in the concave end 2d of the receptacle 5, then by inserting the rest of the body of the block 4 forming the stock rail into the receptacle 5 such that the beveled second end of the block 4 is also positioned in the complementary arrangement 2e of the receptacle 5 of the single-piece structure 2 and the rolling surfaces, on the one hand, of the block 4 forming the stock rail and, on the other hand, of the single-piece structure 2 are positioned level with one another, so as to exhibit rolling surface continuity. id="p-35" id="p-35"

[0035] Obviously, the invention is not limited to the embodiments described and represented in the attached drawings. Modifications remain possible, notably from the point of view of the construction of the various elements or through the substitution of technical equivalents, without in any way departing from the scope of protection of the invention.

Claims (11)

15 Claims

1. [Claim 1] An assembly for switches and crossings (10) defining a direct track (A) and a diverted track (B) comprising: - a single-piece structure (2) comprising a receptacle (5), - a switch point rail (3) movably mounted on the single-piece structure (2), characterized in that the assembly comprises at least one block (4) forming the stock rail, the block (4) being removably mounted in the receptacle (5) on a dedicated part of the single-piece structure (2), this receptacle (5) being of a form complementing the block (4) forming the stock rail and configured to allow the positioning therein of the block (4) by insertion, such that this receptacle (5), on the one hand is open at the top and toward the switch point rail (3) movably mounted on the single- piece structure (2) and, on the other hand, is produced in such a way as to comprise at least a surface of the lateral portion (2b) of the single-piece structure (2) and a surface of the base (2a), such that these two surfaces (2a, 2b) produce between them a concavity configured and intended to receive the removable block (4) forming the stock rail.

2. [Claim 2] The assembly as claimed in claim 1, characterized in that the assembly comprises at least one device for vertically and/or horizontally retaining the block (4) forming the stock rail positioned in the receptacle (5).

3. [Claim 3] The assembly as claimed in one of claims 1 and 2, characterized in that the single-piece structure (2) comprises a relief disposed on a surface of the receptacle (5) and intended to interact with a surface of the block (4) forming the stock rail. [

4. Claim 4] The assembly as claimed in one of the preceding claims, characterized in that the assembly also comprises a locking piece (7) configured to be fixed to the single-piece structure (2) and comprising at least one bearing surface (7a) intended to interact with a surface of the 16 block (4) forming the stock rail so as to press the block (4) against the single-piece structure (2).

5. [Claim 5] The assembly as claimed in claim 4, characterized in that the locking piece (7) is configured to prevent the translation of the block (4) forming the stock rail along at least one horizontal axis.

6. [Claim 6] The assembly as claimed in one of claims 4 and 5, characterized in that the locking piece (7) is configured to interact at at least one of the ends of the block (4) forming the stock rail.

7. [Claim 7] The assembly as claimed in one of claims 1 to 6, characterized in that, in a substantially horizontal plane, at least one first end of the block (4) forming the stock rail has a construction of pointed convex form arranged to cooperate with an end of concave complementary form (2d) of the receptacle (5) borne by the single-piece structure (2).

8. [Claim 8] The assembly as claimed in one of the preceding claims, characterized in that the block (4) forming the stock rail is produced from a steel of higher strength and/or better welding capacity than the steel of the single-piece structure (2).

9. [Claim 9] The assembly as claimed in one of the preceding claims, characterized in that at least one surface of the block (4) forming the stock rail intended to bear against the single-piece structure (2) comprises at least one receptacle (8) configured to incorporate a heating element (9).

10. [Claim 10] The assembly as claimed in one of the preceding claims, characterized in that the receptacle (5) of the single-piece structure (2) has an opening at the top and toward the switch point rail (3) movably mounted on the single-piece structure (2), so as to form an arrangement configured to access, by the top face of the single-piece structure (2), the block (4) forming the stock rail so as to separate the block (4) forming the stock rail from its support formed by the single-piece structure (2).

11. [Claim 11] Switches and crossings (10) comprising at least one assembly as claimed in one of claims 1 to 10.