Heating for railway switches

Abstract

 Rail switch assembly having pairs of rails and a basis therefor, wherein each pair of rails comprises a fixed rail and a movable rail or switch tongue, wherein at regular intervals mounting plates/slide plates have been provided for supporting the rails and forming a slide surface for the switch tongues, wherein the rails each comprise a foot and a web extending upwards from the foot, wherein the foot has an upper surface and a lower surface and the web has a first side surface and a second side surface opposite thereto, comprising a heating means for at least one rail of at least one pair of rails, for instance a heating element extending alongside it that has been placed against one or more of the said surfaces, wherein of said pair of rails at least one of both rails has been provided with a first body of thermally insulating material, that has been arranged against at least a part of the lower surface of the foot of said rail and in longitudinal direction extends at least partially between the mounting plates/slide plates for said rail.

Description

[0001] The invention relates to a heating for switches in railways.

[0002] Switch heating systems are known in many embodiments. In one type of system elongated heating elements have been laid along and against the rail. The heating elements can be working on electricity or liquid, wherein the heat is transferred to the rail by contact, or on gas/air, which, heated, is transferred locally to the rail. The heating elements can be placed against the side of the web of the rail or on the foot.

[0003] To limit heat losses it is known to arrange heat insulating material against the rail, see for instance US patent 4.429.845 and DE patent application 26 10 263. The forms of heat insulation shown there comprise, as compared to the heating elements, a considerable bulky body extending in rail direction, in the first case at the side of the heating element, surrounding said element, in the second case at the opposite side.

[0004] At the location of the switches the fixed rails and the switch tongue are supported on mounting plates and slide plates, respectively, which usually form one unity with each other and provide a mounting location for the fixed rail and a slide surface for the switch tongue, respectively, and have been attached to either a concrete basis or on sleepers, which in turn are supported on a ballast bed. Between two successive mounting plates/slide plates, below the foot of the rail secured thereto and above the basis an intermediate space is formed. Said space is larger (higher) when supported on sleepers than when supported on a concrete basis. Said intermediate space offers room to snow and forms a passage for cold wind. As a result thereof large heat losses may occur in the foot of the rail.

[0005] It is an object of the invention to provide a rail assembly with which the heat losses in a heating system for switches can be limited.

[0006] According to one aspect the invention for that purpose provides a rail switch assembly having pairs of rails and a basis therefor, wherein each pair of rails comprises a fixed rail and a movable rail or switch tongue, wherein at regular intervals mounting plates/slide plates have been provided for supporting the rails and for forming a slide surface for the switch tongues, wherein the rails each comprise a foot and a web extending upwards from the foot, wherein the foot has an upper surface and a lower surface and the web has a first side surface and a second side surface opposite thereto, comprising a heating means for at least one rail of at least one pair of rails, for instance a heating element extending alongside it that has been placed against one or more of the said surfaces, wherein of said pair of rails at least one of both rails has been provided with a first body of thermally insulating material, that has been arranged against at least a part of the lower surface of the foot of said rail and in longitudinal direction extends at least partially between the mounting plates/slide plates for said rail. In that way the portion in question of the lower surface of the foot is not only insulated against emission of heat by radiation, but contact of said part with cold air streaming past said surface is also prevented, as well as direct contact with snow. In this case body means that the body can be separately/individually handled and does not collapse, like a blanket, but has some bending stiffness preventing such. The first body thus can be block-shaped, of synthetic foamed material, such as EPP, PUR or EPS.

[0007] Preferably, considered in a vertical plane of cross-section, the first body extends onto or preferably to below the lower side of the mounting plates or slide plates. In that way the said passage is limited in size. In case of support on sleepers the first body may also extend to below the upper side of the sleepers.

[0008] In one embodiment the first body also abuts a first side surface of the foot that faces away from the other rail of the pair in question and/or the first body also abuts a second side surface of the foot that faces the other rail of the pair in question.

[0009] In one embodiment the length of the first body substantially corresponds with the intermediate distance between the mounting plates or slide plates. The fixed rails can then be situated with their foot directly on the mounting plate in the usual manner.

[0010] The thermal insulation according to the invention can be combined with a second body of thermally insulating material that has been arranged against at least a part of the first or the second side surface of the web and extends in longitudinal direction of the rail. Said second body can at least partially be continuous over several mounting plates.

[0011] As regards material the second body may correspond with the first body.

[0012] In one embodiment the second body also abuts a first side surface of the foot that faces away from the other rail of the pair in question.

[0013] The first and second body can also be arranged against the upper surface of the foot. The first and the second body may extend to near each other, particularly against each other, in which case also said first side surface of the foot is insulated. For instance the first body, when separate from the second body, may comprise a portion that abuts the upper surface of the foot. Alternatively said portion may be part of the -separate- second body.

[0014] In a first further embodiment, especially suitable for fixed rails, the length of the second body substantially corresponds with the intermediate distance between the mounting plates, as a result of which the second bodies can be easy to handle and place. In a second further embodiment that is also highly suitable for fixed rails, the length of the second body substantially corresponds with the centre-to-centre distance of the mounting plates, for instance 60 cm. In that case the insulation material, optionally after having been cut to size, optionally at least for a part of its cross-section can almost continue at the location of the fastening means for the rails on the mounting plate, as a result of which at that location an interruption in the insulation is kept limited.

[0015] In one embodiment that is particularly suitable for movable rails the second body continues over several slide plates.

[0016] Preferably the first and the second body form one unity with each other, as a result of which handling and placing can be facilitated. In that case as well said first side surface of the foot is insulated. The part of the body thus obtained that is situated above the lower surface of the foot can then continue further, in accordance with the discussion above of the second body.

[0017] The first and/or, when present, the second body can be secured to the rail as a result of clamping action. In case the first and second body have been formed as one unity a clamping action can be obtained by internal resilience in the integrally formed assembly of the first and second body, in which way mounting is simplified.

[0018] Alternatively or additionally, a clamping action can be obtained by added clamps, such as clamping brackets, wherein the first and second body may or may not be integrally formed.

[0019] When the rail, as usual, on top of the web has been provided with a rail head that is broadened with respect to the web, and the first or, when present, the second body, abuts a side surface of the web, it extends to a distance below the rail head, as a result of which a tamper machine is able to have sufficient grip on the rail in question in order to lift it.

[0020] The first body can be provided with a slot for accommodation of at least a part of the foot, wherein the body abuts a lower surface, a first side surface and an upper surface of the foot. The body may furthermore also abut at least a lowermost portion of a side surface of the web and/or also abut a second side surface of the foot situated opposite the first side surface of the foot.

[0021] The slot can be downwardly bounded by a leg of the body, that can resiliently be bent away from the rest of the body for temporary broadening of the slot during placement. The resilience can be such that the leg and the rest of the body exert a spring clamping force on the rail.

[0022] When use is made of a body of thermally insulating material continuing over several mounting plates/slide plates, the part of said body that is intended to be placed against the lower surface of the foot can be provided with an interruption for accommodation of the mounting plates/slide plates.

[0023] At the level of the web of the rail, the first and/or second body may have a horizontal dimension that at least substantially corresponds with the length of protrusion from the foot, considered in a plane of cross-section.

[0024] The first and optionally the second body can be arranged on the rail that has also been provided with a heating element. The first and optionally the second body can be arranged on both rails of a pair or on one (fixed rail of switch tongue) of them.

[0025] The heating element can also be clamped against the rail in question by clamping action. Preferably use is then made of the clamping facility for the first or second body present, such as the said inherent resilience in the first or second body or by using an added spring clamp or clamping bracket that also clamps the first or second body against the rail in question.

[0026] The first and/or second body can be outwardly shielded by a cover plate, which protects the material of the body against moisture, sparks and UV radiation. The cover plate can be adhered to the body in question, before or optionally after placing the body, or be clamped against it.

[0027] Due to the increasing intensity of train traffic the noise production of the trains riding over the rails is increasingly considered a problem. This is the case for straight sections, but also in bends, and also in switch series.

[0028] Several proposals have been made to limit the noise production.

[0029] WO 99/15732 suggested a silencer consisting of two rigid, solid, elongated resonance members having different effectiveness, which for instance have been made of steel, and one or more layers of a deformable material such as rubber. The silencer is placed on the foot and against the web of the rail.

[0030] GB patent application 2.421.265 suggested a silencer in laminate shape, having a metal layer and an elastomere layer that is arranged against the upper surface and the side of the foot.

[0031] In DE utility model 297 14 904 a multiple silencer system is shown, having a silencer member against the lower side of the foot of a rail and a silencer member against the web of the rail, wherein each silencer member forms a multiple mass-spring system, also see DE patent application 31 13 268.

[0032] Through DE patent application 37 22 439 it is known to use rubber blocks which by means of a magnetised rubber plate have been placed against both sides of the web of a rail.

[0033] From DE patent application 43 22 468 a two-sided silencer assembly is also known, wherein against both sides of the web a rigid synthetic part is placed with an elastomere layer in between.

[0034] From EP patent application 0.628.660 it is known to fill the cavities on both sides of the web of a rail with a material having a low density, described as a polymer filled with finely distributed cells, for instance cork particles. In one embodiment the material can be cast in situ and a rod having a considerable higher specific gravity is accommodated therein.

[0035] According to a further aspect the invention provides a rail switch assembly having pairs of rails and a basis therefor, wherein each pair of rails comprises a fixed rail and a movable rail or switch tongue, furthermore comprising a heating means for at least one rail of at least one pair of rails, such as a heating element extending alongside a rail, wherein of said pair of rails at least one rail is provided with a body of thermally insulating material, wherein said body of thermally insulating material is provided with an added solid sub body having a density that exceeds the density of the material of the body of thermally insulating material.

[0036] Thus the function of sound damping is combined with the function of thermal insulation in one object. Depending on the way of attachment the one body is able to carry the other body at least partially, or make use of the fastening means for the other body, as a result of which the arrangement can be remain simple in the end.

[0037] The choice of the mass of the added sub body also depends on the desired action and frequency range, as is also emphasized in the above-mentioned patent documents. The added sub body may have a mass of at least some kg/m' and preferably has a mass of over 1000 kg/m³, preferably over 5000 kg/m³.

[0038] In one embodiment the added sub body is at least partially accommodated in the body of thermally insulating material. The added sub body may in a direction facing away from the rail and in upward direction be covered by material of the body of thermally insulating material. The added sub body can in downward direction moreover be covered by material of the body of thermally insulating material. The sub body can in that case be virtually surrounded by the thermally insulating body, considered in cross-section. Means for retaining said latter body in its place against the rail can directly or indirectly retain the sub body in its place, at least contribute thereto.

[0039] In one embodiment a layer of elastic material is situated between the -rigid-added sub body and the rail, which layer is attached to the rail and to the sub body. In that way a mass spring system can be formed.

[0040] This system too can be used on the fixed rail and/or on the switch tongue.

[0041] According to a further aspect the invention provides a thermally insulating body apparently intended and suitable for a rail switch assembly according to the invention.

[0042] According to a further aspect the invention provides a switch for a rail, comprising a number of mounting plates/slide plates and fixed rails attached thereto as a well as a pair of movable rails or tongues, wherein at least one of the rails is provided with a weighted part for noise reduction.

[0043] The weighted part, comparable per se to the said sub body, can be part of a mass spring system that is attached against the rails.

[0044] The weighted part can have a density of over 1000 kg/m³, preferably over 5000 kg/m³.

[0045] The weighted part can at least partially be accommodated in a body of thermally insulating material, wherein the rail can be provided with a heating element extending alongside it and abutting the rail.

[0046] As stated earlier the rail can be a fixed rail or a moveable rail of tongue.

[0047] The aspects and measures described in this description and the claims of the application and/or shown in the drawings of this application may where possible also be used individually. Said individual aspects may be the subject of divisional patent applications relating thereto. This particularly applies to the measures and aspects that are described per se in the sub claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The invention will be elucidated on the basis of a number of exemplary embodiments shown in the attached drawings, in which:

Figure 1 shows a top view of a switch of a railway, provided with a thermal insulation according to the invention;

Figures 2A and 2B show details of the switch of figure 1;

Figures 3A-E show a few cross-sections and a side view of exemplary embodiments of arrangements according to the invention including thermal insulation; and

Figure 4A-E show a few cross-sections and an isometric view of exemplary embodiments of arrangements according to the invention including noise reduction.

DETAILED DESCRIPTION OF THE DRAWINGS

[0049] The switch arrangement 1 of figure 1 comprises a number of fixed rails 2a, 2b and two switch tongues 3a, 3b, that are supported on sleepers 4 that are borne by a ballast bed 6 of rubble. On the sleepers 4 mounting plates 16 with mounting brackets 17 have been attached, which plates 16 in the usual manner also form slide plates 5, over which the switch tongues 3a, 3b are able to slide when changing the switch 1.

[0050] Figures 2A and 2B show that the rails, in detail of figure 2B the rails 2a and 3a, have each been provided with a heating pipe 10 attached thereto, as well as with an elongated block 11, 12, 13 of thermal insulation material, such as EPP, PUR or EPS or combinations thereof. The pipe 10 and the block 11 have both been secured to the rail 2a by means of resilient clamping brackets 14, at the opposite sides of the rails 2a. The block 12 is clamped against the lower side of the rail 2a by the bracket 14. The pipe 10 and the block 13 are both secured to the rail 3a by means of a resilient clamping bracket 15, at the same side of the rail 3a.

[0051] Figure 2A schematically shows that a passage 7 is formed between the sleepers 4, the ballast bed 6 and the rail 2a.

[0052] In figures 2A and 2B the blocks or bodies 11 and 12 are separate units, second and first bodies, respectively, of thermally insulating material, which just like block or body 13 have sufficient bending stiffness to be handled separately when being placed. In an embodiment that is not shown the blocks 11 and 12 may abut each other, wherein the foot of the rail at the side of the block 11 is entirely surrounded by the thermal insulation material. The block 13 continues over a number of sleepers. The block 11 has a length to fit exactly between the mounting plates 16 with brackets 17.

[0053] It is also possible to let the blocks 11 and 12 form one unity, as shown with block 12 in figures 3A and 3B. The rail 2a comprises a head 21, a web 20 and a foot 22. The block 12/11 with a portion 11 abuts first side surface 20a of the web 20, with portion 12a abuts upper surface 22a of the foot 22, with portion 12b abuts first side surface 22b of the foot 22, with portion 12c abuts the lower surface 22c of the foot 22 and with portion 12d, which forms a raised edge, abuts the other, second side surface 22d of the foot 22. Between the portions 12a and 12c/d of the block 12 a slot 19 is left open in which the foot 22 is fittingly accommodated.

[0054] The block 12 shown in figures 3A and 3B may have a length that corresponds with the intermediate distance of the sleepers. The grey strips 12' on the drawing above the mounting brackets 17 in that case have to put out of mind. It is also possible to make use of blocks having a length that corresponds with the centre-to-centre distance of the sleepers. In addition prior to placement, material at the ends of the block is cut away, so that with the resulting narrower portions 12' mounting members 16/17 can be reached over in order to thus provide partial insulation indeed on the mounting location of the rail. The end sections of the portions 12b-d have been cut away too in order to offer room to the sleepers and to connect snugly thereto.

[0055] When placing the block 12 the slot 19 between portions 12a and 12c can be manually broadened in direction B, so that the block 12 can be slid on the foot 22, direction C, from aside. An inherent resilience in the block 12 ensures that the leg 12b-d moves back in order to clamp about the foot. The thickness of portion 12b is also sufficient to prevent fracture when broadening the slot 19. If so desired the position of the block 12 can be locked with resilient clamping brackets 14.

[0056] The block may also have been provided with a cover plate 70 for shielding the material of the block 12 against UV radiation, moisture and sparks. The cover plate 70 can be made of a metal or a synthetic material suitable for the shielding purposes. The cover plate 70 can be attached to the block 12 by adhesion or it can be opted for to place it on/about the block and to utilise the clamping brackets 14 for the block 12 also for keeping the cover plate 70 in its place, as shown in figure 3A.

[0057] In figure 3A the switch tongue 3a, just like in figures 2A and 2B, has a smaller height than the rail 3a, which is common in for instance Germany. The rail 3a here comprises a pointed head 31, a web 30 and a foot 32. In the closed condition of the switch tongue 3a, a space 8 is left between the webs 20, 30 of both rails 2a, 3a, and below the foot 32 of the rail 3a and the foot 22 of the rail 2a there is a space 9 between the sleepers. The space 9 allows the pipe 10 to be laid between the sleepers on the foot 22. Although the rail 3a itself has not been provided with a heating element, it has nonetheless been provided with a block or a body of thermally insulating material 13, secured with a clamping bracket 15, in order to counteract losses in the heat received indirectly from pipe 10.

[0058] Figure 3B shows that above the sleepers 4, where means 16/17 for attachment of the rails 2a on the sleepers 4 have been provided, the bodies 11 and 12, that may or may not have been integrally formed, have been interrupted. It is noted that for reasons of simplicity of the drawing this is not shown in figures 2A and 2B. Mounting plates 16 with mounting brackets 17 can be seen, which brackets with a counter part situated at the other side clamp the rail fixed and with bolt/nut have been attached to the sleeper 4. At the other side of the rail 2a the mounting plate 16 changes into a slide plate. On both sides of the interruptions clamping brackets 14 have been arranged.

[0059] The block or body portion 11 does not extend up to the head 21, but ends at a distance below therefrom and thus leaves a space D open for tools of a tamper machine that is able to pick up the head 21 properly.

[0060] It can be seen in figure 3B that portions 12b and 12c extend adjacent to and below the foot 22 of the rail 2a, between the locations of attachment of the rail 2a on the sleepers 4. As a result the mounting and the location of the rail 2a on the sleepers 4 is not influenced, but the rail 2a is nonetheless thermally insulated to a high degree, also above the intermediate space where passage 7 has been formed. Furthermore the said passage 7 is made smaller in that way.

[0061] The arrangement shown in figure 3C corresponds to some extent to the one of figures 2A and 2B, the difference being that the in cross-section L-shaped body 12 does not abut the side surface 22b of the foot 22. In comparison with figure 3A the bodies 11 and 12 are separate bodies, wherein side surface 22b offers direct support to clamping bracket 14.

[0062] The arrangement of figure 3D shows a switch tongue 103a as for instance used in the Netherlands. The foot 132 of the rail 103a is situated at the same level as the foot 1122 of fixed rail 102a. Comparable parts have the same numbers as before, increased by 100. Again there is question of two separate bodies 111 and 112 on rail 102a. The thermally insulating body 113 surrounds a heating pipe 110 and is clamped in its place against the rail 103a by means of a clamping leaf spring 115, that is rotatably attached to a fixed bracket 115a.

[0063] The arrangement of figure 3E shows a thermally insulating body 111 on rail 102a, which body does not touch the lower side of the foot 122 and extends up to against the head 121. In this case the foot 132 of switch tongue 103a is provided with an integrally formed elongated block or body of thermally insulating material 113, defining a slot 119 and with leg 113c abutting a lower surface 132c of the foot 132 and with portion 113b abutting side surface 132b of the foot 132. Here as well there can be question of clamping action due to inherent resilience in body 113. The thickness of portion 113b is also sufficient to prevent fracture when broadening the slot 119. A clamp 115 has been added for extra reliability. At the location of the slide plates the body 113 may continue, but at the location of the slide plates, because of contact of the rail 103a with the slide plate, portion 113c will not be there.

[0064] In an embodiment that is not shown, the body 12 can be U-shaped, and abut the lower surface and against both (first and second) side surfaces of the foot of the rail. In addition a separate block or body 11 can be placed against the web and the upper surface of the foot.

[0065] It is noted that the length, in a plane of cross-section, over which the lower surface of the foot of the rail is shielded by the body of thermally insulating material can also be shorter, although then optionally shielding a side surface of the foot, particularly at the location of the second side surfaces thereof, will have to be given up.

[0066] Furthermore the bodies of thermally insulating material may at least partially extend over several sleepers, for instance provided with recesses at the location of sleepers. The bodies may be coated with a UV-protective layer. The bodies may also be of use in case of high ambient temperatures.

[0067] In figures 4A-D the arrangements are shown in which the elongated block or body of thermally insulating material offers room to a block or body of a relatively high mass, for instance comparable to that of steel.

[0068] In figure 4A the block 211, as regards material comparable to the blocks 11, 12, 13 discussed above, forms an accommodation space 250. In the accommodation space 250 an elongated rigid block of steel 240 is fittingly accommodated. The block 240 is fixedly attached to a layer 241 of elastic material, such as synthetic rubber, that is adhered to side surface 220a of body 220. At the lower side the block 240 is supported by portion 211e of block 211, which in turn supports on the foot 222. Sidewards, the block 240 is retained against displacement away from web 220 by wall 211f of block 211, and upwardly covered by upper wall 211g of block 211. The block 211 is clamped in its place by clamping bracket 214.

[0069] Block 240 and layer 241 form a mass spring system for damping noise generated by material riding over the rail. The mass per running meter depends on the frequencies at which the damping system has to be active.

[0070] In figure 4B a narrower block 240 is shown. Furthermore at that location an accommodation space 251 has also been provided in the block 213 on the switch tongue 203a, in which accommodation space a block 242 of for instance steel has been accommodated. A layer 243, comparable with layer 241, connects block 242 with surface 320a of web 320 of rail 203a.

[0071] The arrangement of figure 4C slightly corresponds with the one of figure 4A, yet instead of the clamping bracket now a bracket 314 is used for securing the block 311 against the rail 302a, also see figure 4D. The bracket 314 extends between two successive sleepers 4, and comprises portions 314a-c, wherein portions 314a have been attached to the mounting plates/brackets 316/317 by bolts/nuts. A threaded end 318 is rigidly attached to the steel block 340 and extends through the block 311 and a hole in bracket portion 314c. By means of a nut 317 the longitudinal portion 314c is pressed against the block 311, so that the bracket 314 keeps both the block 311 and the block 340 in their place against the rail 302a. Here as well the block 311 may offer support to the block 340. Note that the bracket 314 in figure 4C slightly differs from the one of figure 4D due to the course of portion 314b, which course is inclined or at angles, respectively.

[0072] In the arrangement of figure 4E use is made of a bracket 414 as well, but it does not extend in longitudinal direction and is attached to a rail foot clamp 416 that is known per se, and which by means of a tension bolt 417 is secured to the rail 402a at a location between the sleepers and engages onto both sides of the foot 422.

[0073] At the longitudinal ends of the blocks 211, 311 and 411, the accommodation spaces 250, 251, 350 and 450 have been closed off by material of those blocks, as schematically shown in figure 4D.

[0074] The above description is included to illustrate the operation of preferred embodiments of the invention and not to limit the scope of the invention.

[0075] Starting from the above explanation many variations that fall within the spirit and scope of the present invention will be evident to an expert.

Claims

1. Rail switch assembly having pairs of rails and a basis therefor, wherein each pair of rails comprises a fixed rail and a movable rail or switch tongue, wherein at regular intervals mounting plates for the fixed rails and slide plates that preferably have been integrally formed with the mounting plates for forming a slide surface for the switch tongues are provided, wherein the rails each comprise a foot and a web extending upwards from the foot, wherein the foot has an upper surface and a lower surface and the web has a first side surface and a second side surface opposite thereto, comprising a heating means for at least one rail of at least one pair of rails, for instance a heating element extending alongside it that has been placed against one or more of the said surfaces, wherein of said pair of rails at least one of both rails has been provided with a first body of thermally insulating material, characterised in that said first body has been arranged against at least a part of the lower surface of the foot of said rail and in longitudinal direction extends at least partially between the mounting plates or slide plates for said rail.

2. Rail switch assembly according to claim 1, wherein considered in a vertical plane of cross-section, the first body extends onto, preferably to below the lower side of the mounting plates or slide plates, in case of support on sleepers preferably to below the upper side of the sleepers.

3. Rail switch assembly according to claim 1 or 2, wherein the first body also abuts a first side surface of the foot that faces away from the other rail of the pair in question and/or also abuts a second side surface of the foot that faces the other rail of the pair in question.

4. Rail switch assembly according to claim 1, 2 or 3, wherein the rail has furthermore been provided with a second body of thermally insulating material arranged against at least a part of the first and or the second side surface of the web and extending in longitudinal direction of the rail, wherein, preferably, the second body can also abut a first side surface of the foot that faces away from the other rail of the pair in question.

5. Rail switch assembly according to any one of the preceding claims, wherein the first or second body has been arranged against the upper surface of the foot.

6. Rail switch assembly according to any one of the preceding claims, wherein the first and the second body extend to near each other, particularly against each other or wherein the first and the second body form one unity with each other.

7. Rail switch assembly according to any one of the preceding claims, wherein the length of the first body and/or the length of the second body substantially corresponds with the intermediate distance between the mounting plates or the slide plates.

8. Rail switch assembly according to claim 4, 5 or 6, wherein the length of the second body substantially corresponds with the centre-to-centre distance of the mounting plates or the slide plates, for instance 60 cm, or wherein the second body continues over several mounting plates or slide plates.

9. Rail switch assembly according to any one of the preceding claims, wherein the first body has been provided with a slot for accommodation of at least a part of the foot, wherein the first body abuts a lower surface, a first side surface and an upper surface of the foot, preferably also abuts at least a lowermost part of a side surface of the web, wherein, preferably, the first body also abuts a second side surface of the foot situated opposite the first side surface of the foot.

10. Rail switch assembly according to claim 9, wherein the slot is downwardly bounded by a leg of the first body, that can resiliently be bent away from the rest of the first body for broadening the slot during placement, wherein, preferably, the leg and the rest of the first body exert a spring clamping force on the rail, wherein the clamping action has preferably at least been obtained by internal resilience in the first body.

11. Rail switch assembly according to any one of the preceding claims, wherein the rail on top of the web has been provided with a rail head that is broadened with respect to the web, wherein when the first body or, when present, the second body, abuts a side surface of the web, yet extends to a distance below the rail head.

12. Rail switch assembly according to any one of the preceding claims, wherein the first body continues over several slide plates, wherein the part of the first body that is intended to be placed against the lower surface of the foot for accommodation of the slide plates has been provided with an interruption.

13. Rail switch assembly according to any one of the preceding claims, wherein the first body has been arranged on the rail that has also been provided with a heating element.

14. Rail switch assembly according to any one of the preceding claims, wherein the first body and/or the second body, when present, is secured on the rail by clamping action, for instance by inherent resilience in the body or by using an added spring clamp or clamping bracket, which preferably also clamps a heating element against the rail in question.

15. Rail switch assembly according to any one of the preceding claims, wherein the rail is a fixed rail or wherein the rail is a movable rail or tongue.

16. Rail switch assembly according to the preamble of claim 1 or according to any one of the preceding claims, wherein the said body of thermally insulating material is provided with an added solid sub body having a density that exceeds the density of the material of the body of thermally insulating material.

17. Rail switch assembly according to claim 16, wherein the added sub web has a mass of at least some kg/m' and preferably has a mass of over 1000 kg/m³, preferably over 5000 kg/m³.

18. Rail switch assembly according to claim 16 or 17, wherein the added sub body is at least partially accommodated in the body of thermally insulating material.

19. Rail switch assembly according to claim 18, wherein the added sub body in a direction facing away from the rail and in upward direction is covered by material of the body of thermally insulating material.

20. Rail switch assembly according to claim 19, wherein the added sub body in downward direction is covered by material of the body of thermally insulating material.

21. Rail switch assembly according to any one of the claims 16-20, wherein between the rigid added sub body and the rail a layer of elastic material is situated that is attached to the rail and to the sub web for forming a mass spring system.

22. Thermally insulating web apparently intended and suitable for a rail switch assembly according to any one of the preceding claims.

23. Switch for a rail, comprising a number of mounting plates/slide plates and fixed rails attached thereon as well as a pair of movable rails or tongues, wherein at least one of the rails is provided with a weight member for noise reduction.

24. Switch according to claim 23, wherein the weight member is part of a mass spring system attached against the rails.

25. Switch according to claim 24, wherein the weight member has a density of over 1000 kg/m³, preferably over 5000 kg/m³.

26. Switch according to any one of the claims 23-25, wherein the weight member is at least partially accommodated in a body of thermally insulating material.

27. Switch according to claim 26, wherein the rail is provided with a heating element extending alongside it and abutting the rail.

28. Switch according to any one of the claims 16-27, wherein the rail is a fixed rail.

29. Switch according to any one of the claims 16-27, wherein the rail is a movable rail or tongue.

Drawing