VICE DEVICE FOR HEATING CABLES IN A RAILROAD SWITCH

Abstract

 The present invention refers to a vice device (1) for locking the heating system (100, 200) in a point (10) of a switch point, the device comprising:
- A front striker (2) and a rear striker (4, 5) between which the point of the switch point is constrained;
- Clamping elements (3, 30) which connect the front striker to the rear striker (4, 5) so as to adjust the reciprocal distance between the front striker and the rear striker adjusting the clamping degree acting on the point.

Description

Field of the invention

[0001] The present invention relates to the technical field of railways.

[0002] In particular, the invention relates to an innovative locking vice device enabling to readily and practically fasten the heating cables to the superstructure of the switch point with moveable point frog, generally of self-regulating type.

Brief outline of the prior art

[0003] Railroad switches have long been known and in general, they consist in a part of moveable track which is moved for bringing it close/drawing it away from another track so as to make the train passing on it change direction.

[0004] The switch point in tracks for high-speed trains is composed by two parts: the point stock and the moveable point frog.

[0005] The latter component, known per se in the prior art, enables a smooth and safe passage of the train through the particular mechanical kinematic motion, even high-speed trains. In fact, there is no mechanical interruption in the point of intersection between the two tracks for making the flange of the truck pass. In railways for low-speed trains, this system is called switch point with fixed crossings.

[0006] The moveable point frog is mechanically constituted by a metallic tip (point), mechanically arranged between two sections of track and activated by oil-pressure actuators which enable its movement from one side to the other side to the full collision with the track.

[0007] It is also necessary to heat the moveable point frog with self-regulating heating cables because of problems of lock to the switch point due to the ice formation in winter time.

[0008] In the prior art, these cables are supplied with extra-low voltage 24V and the input thereof varies depending on the temperature of the metallic body to which they are firmly fastened.

[0009] The fastening of these cables to the superstructure with moveable point frog is very complicated because of different factors: high vibrations, complexity of the mechanical architecture, dynamism of mechanical parts and eventually very reduced distances. Moreover, the tolerance of application of cables are strict, as any mechanical obstacle interposing between the point and the two tracks would cause the automatic block of the train circulation.

[0010] Therefore, current fastening systems are complex to arrange and not very functional.

[0011] Moreover, it is obvious that even a partial detachment of these cables implies an insufficient heat for deicing in the detachment area and this can have a very strong impact on the correct functionality of the switch point and therefore on safety.

[0012] In the railway field, systems using clamps to lock the heating cables are known in the prior art.

[0013] For example, the publication US4429845 and the publication DE102013016232 are known, both corresponding to the preamble of claim 1.

[0014] Nevertheless, the solution with clamps described in the prior art cannot be used in a switch point with moveable point frog for high-speed trains, because the structure thereof would not enable the application and the safe fastening of the cables to the tracks of this kind of switch point.

[0015] In particular, the solutions described in the prior art are cumbersome and only enable the fastening of the hot cable to the external part of a "traditional" switch point, thus making impossible an application between point and stock rail of the system with moveable point frog for high-speed trains. The particular shape of this superstructure with moveable point frog and the narrow gauge between stock rail and point do not enable the use of systems described in the prior art.

Summary of the invention

[0016] Therefore, the aim of the present invention is to provide an innovative device, which resolves at least in part said technical disadvantages.

[0017] In particular, the aim of the present invention is to provide an innovative vice device capable of enabling the fastening of the heating cables in a switch point in simple and efficient manner, thus avoiding accidental detachments.

[0018] Therefore, these and other aims are achieved with the present vice device 1 for locking the heating system (100, 200) against the surface (10") of a point (10) or preferably of a stock rail of a switch point, preferably with moveable point frog, according to claim 1.

[0019] This vice device (1) comprises:

• A front striker (2), configured to be applied in use to a slab (10') of a track (10) and a rear striker (4, 5) configured to be applied onto the web (10") of the same track (10);
• According to the invention, clamping elements (3, 30) are further comprised, connecting the front striker (2) to the rear striker (4, 5) so as to adjust the reciprocal distance thereof.

[0020] In this manner, through the aforesaid clamping elements (3, 30) the front striker and the rear striker can be moved close to each other while they trap the stock rail (or the point if it is applied to the moveable part) between them, thus enabling a clamping effect which can be adjusted depending on need, just like a vice.

[0021] These clamping elements can be for example in form of tension rod which connects the two parts to each other and formed by a threaded pivot ad a screw, like a traditional vice. Acting on the screw applied to the tension rod, the two parts are moved close to each other by clamping to a certain desired degree the track section comprised between said two parts.

[0022] The rear striker which is clamped towards the front one pushes onto the surface of the stock rail where the cables are applied, generally contained in a protective wireway, thus creating a clamping of these cables which efficient and easy to activate.

[0023] In the study of this particular setup, close attention has been paid to the above-mentioned point, therefore the developed fastening system is mini-invasive, with reduced encumbrance and built-in safety in the event of breakages.

[0024] The heating cables are protected and held by half-wireway, preferably of steel, which form a kind of metallic shell giving at the same time mechanical protection and uniform distribution of pressure along the whole superstructure affected by the heating.

[0025] The device, which traps the said stock rail within it, causes an adjustable pressure onto the wireway, maintaining the cables in position, with a simple and fast installation.

[0026] These wireways are accurately pushed to the track by this vice device with tension rod, according to the present invention.

[0027] This solution enables to act with a firm fastening even on a superstructure whose slab of the two tracks is tapered off in the internal part and therefore even with conditions which would cause a difficult fastening in the prior art, due to the presence of high vibrations.

[0028] Advantageously, these clamping elements comprise a tie rod element (3).

[0029] Advantageously, this tie rod element (3) comprises a rod (3) threaded at least in part and a clamping element (30) configured to be screwed onto the thread of said rod.

[0030] Advantageously, said clamping element (30) is a bolt or similar ones.

[0031] Moreover, advantageously, anti-unscrewing elements may be comprised (31).

[0032] Advantageously, said clamping elements, preferably in the form of said threaded rod, are permanently fastened to the rear striker (4, 5) and are connected in sliding manner with respect to the front striker (2).

[0033] Advantageously, said front striker (2) comprises a longitudinal through channel (2'), preferably not threaded, within which said rod inserts in sliding manner (3) so that at least a threaded part of said rod protrudes from said channel thus enabling the application of the clamping element (30) onto said thread.

[0034] Advantageously, said front striker (2) is shaped with a cavity (20) configured to house the shape of the slab of the point to which it is applied.

[0035] Advantageously, said rear striker (4, 5) is generally L-shaped and comprises a lower part fastened to the back of the tie rod (3) and un upper part which stands from the tension rod so as to form a pressure surface (4") which pushes in use onto the surface of the web of the stock rail to which it is applied in use.

[0036] Advantageously, said pressure surface (4") comprises a contact area (5) shaped with a S-shaped buckling (5) so as to retrace the shape of the wireway which contains the electrical cable and against which said contact area (5) pushes in use.

Brief description of the drawings

[0037] Further features and advantages of the present vice device according to the invention will become apparent from the following description of preferred embodiments thereof, given only by way of non-limiting example, with reference to the attached drawings, wherein:

• Figure 1 depicts in a side view the device for fastening the heating system of the moveable point frog;
• Figure 2 is a view from above of figure 1;
• Figures from 3 to 5 extrapolate the single components;
• Figure 6 is a further view from above of a second embodiment of the invention.

Description of some preferred embodiments

[0038] With reference to figure 1 it is described in a lateral view, the vice device 1 subject of the invention.

[0039] Figure 1 depicts a portion 10 of track constituting the fixed part of the switch point and on which the heating system 100 is applied, always schematically depicted in figure 1 and generally named stock rail 10.

[0040] The same concept could be applied to a shape of a track belonging to a moveable part (point).

[0041] The fastening of the whole heating system (vice and electrical cables with wireway) to the fixed part of the superstructure, i.e. to the stock rail, determines in any case in the application area a heat diffusion which also intercepts the running base onto which the point moves and also in part intercepting the point. Therefore, the ice formation on the moveable part is also well prevented in comparison with a simplified application, due to the fact that the described system is preferably applied to a fixed part and not moveable.

[0042] With reference to figure 1, this superstructure comprises a fixed stock rail 10 having a front part named "slab" 10' and a rear part named "web" 10".

[0043] The heating system is constituted by a heating cable supplied with extra-low voltage so as to produce heat by Joule effect and applied to the base of the web 10".

[0044] As described in the prior art, the tension is generally 24V and this determines a circulation of electrical current, as per prior art.

[0045] As depicted in figure 1, the cable passes preferably but not necessarily within the channel which generally belongs to the track and is pre-existing in the track to which it is applied and determines a shape which facilitates the application of the cable.

[0046] The heat produced by the cable during the passage of current enables to avoid the icing of the moveable point frog at very low temperatures.

[0047] In particular, as described above, the ice formation onto the stock rail is prevented, thus enabling a precise approach between point and stock rail. Moreover, the heat spreads also onto the moveable part onto which the ice formation is prevented.

[0048] Therefore, figure 1 depicts in a schematic view, with number 100, the complex of electrical cables which are fastened to the side of the track for example by means of a suitable wireway 200, preferably metallic.

[0049] Therefore, according to the invention, the device subject of the invention enables to readily and safely fasten these cables 100 maintaining them in position as depicted in figure 1.

[0050] For this purpose, the vice device comprises a front part 2 and a rear part (3, 4) which is connected in removable or detachable manner to the front part.

[0051] As described in detail further, the shape of the track to be heated is trapped between the front part and the rear part of the vice. As soon as the necessary clamping is reached, by means of the tie rod, for example in form of a threaded rod 3 and the nut 30, the system is locked with a riveting of a plate 31 arranged behind the nut 30.

[0052] As depicted both in figure 1 and in figure 4, the front part is in form of a block, i.e. a sort of shoe, configured to be fitted into the slab 10'.

[0053] For this purpose, the lock 2 forms a receiving cavity 20 clearly depicted also in figure 4. The slab 10' of the track is inserted within said receiving cavity, exactly as depicted in figure 1.

[0054] In this manner, the lock 2 is constrained to the slab 10' of the track.

[0055] Further, it is comprised a tie rod in form of a threaded rod 3 which is fitted in an axial hole obtained in the lock 2, as depicted in figure 1 and in figure 2. The through hole is preferably unthreaded and it is numbered with number 2' in figure 4. In this manner, being unthreaded, it enables a linear and immediate insertion of the rod 3 in the hole 2' thus avoiding to screw it (this operation is hardly achievable due to the reduced operational space).

[0056] As clearly depicted in figure 1 and 2, the clamping degree may be readily adjusted through a bolt 30, as better described further.

[0057] The rear part 4 is depicted in figure 3 and it is a generally L-shaped striker 4, integral to the tie rod 3.

[0058] The tie rod 3, for example in form of a pivot or rod (in other words), is as already described at least in part threaded in the front part thereof and this striker element (4, 5) is fastened in the rear part thereof.

[0059] The striker element (4, 5) can be for example welded to the pivot.

[0060] The fastening, for example by welding, occurs on the back of the pivot or tie rod and, as described, from the opposite side to the end configured to be inserted in the pivot of the front part 2 and therefore on the opposite part to the thread.

[0061] Therefore, figure 3 depicts with number 60 a welding for connecting the two parts.

[0062] The striker element, as always depicted in figure 3, is generally L-shaped so as to form a base 4' which is connected to the pivot and from which a portion 4" stands in a substantially vertical or even inclined position.

[0063] As depicted in figure 1, the L-shaped shape follows the shape of the stock rail to which it is applied so as to reduce encumbrances and enable the application thereof in a moveable point frog.

[0064] Moreover, the vertical or substantially vertical part of the L-shape is obviously provided with a certain degree of elasticity and flexibility typical of metals, such that, as the vice is clamped, the vertical wall 4" is bent by pushing against the wall of the stock rail, thus locking it firmly with minimum encumbrances.

[0065] Figure 5 well depicts the shape of the vertical part 4" in form of a rectangular plate (generally 4-5 mm of thickness) which is connected to the horizontal part 4' (it is generally a whole) and with the formation of a junction which follows the junction of the track to which it is applied.

[0066] This vertical or inclined wall acts as striker against the opposite part of the track, as depicted in figure 1, locking the wireway of the cables to the surface of application thereof.

[0067] In this manner, by simply inserting the pivot 3 in the hole 2' in sliding manner, it is sufficient to screw the bolt 30 onto the end of the threaded pivot protruding from the hole 2' for causing a translation of the whole tie rod. This translation, depending on the way of rotation, can be a forth motion to the part of the striker 4" with respect to the front part 2, thus creating the desired clamping degree or a back motion.

[0068] With the purpose of better locking the wireway for the passage of cables, the high end of the vertical striker wall 4" includes a pressure element 5, generally metallic and welded to the striker 4", also named shim or thickening.

[0069] This pressure element can be in form of an element with rectangular or square section and, it its whole, it is shaped according to the complementary shape of the wireway 200 which is generally used for containing electrical cables so as to optimize the lock.

[0070] For that purpose, figure 3 depicts in a hatched line with the number 200, the shape of the wireway for highlighting the complementary shape of the element 5.

[0071] As depicted in figure 6, in other possible embodiments of the invention, the striker element (4, 5) can be inclined with respect to the longitudinal axis of the pivot 3 to which it is connected. The angle of inclination is the same of the final shape of the superstructure.

[0072] In all the described embodiments, as depicted in figure 4 and figure 2 for example, through holes (for example two through holes 2") can be comprised on the back of the block 2 for enabling the insertion of screws, for examples Allen screw with pointed end, whose point pushes onto the back of the slab (10') for increasing the fastening constraint.

[0073] The holes 2" are threaded for that purpose.

[0074] The nut 30, which is rotated towards a way or towards the opposite way for causing the back and forth translation motion of the part 2 from the part 4, can be activated through a suitable tool.

[0075] For facilitating the rotation of the nut, it may be also shaped with a small gripping handle, even if this solution is not considered to be optimal because in this case, not only the bolt would have a bigger encumbrance but it would also require a manual clamping and it should not be considered safe.

[0076] Having described the invention structurally, it is now described the assembling and use thereof.

[0077] After having applied the thermal grease facilitating the heat transmission in the application seat of said electrical cables, the subsequent arrangement of the cables 100 within the wireway 200 thereof occurs.

[0078] At this phase, the wireway is pushed against the wall of the track to which it is fastened through the application of the vice device 1.

[0079] For this purpose, it is applied the front part 2 which is coupled to the slab 10' and the pivot 3 is inserted under the slab so as to insert it in the channel 2' .

[0080] The striker 4 is brought into abutment by making the pivot advance into the seat such that the appendix 5 pushes onto the wireway and the fastening occurs by applying and screwing the end bolt 30.

[0081] With the purpose of avoiding a risk of unscrewing the bolt, an anti-unscrewing system is used consisting, as mentioned above, in the riveting of a plate 31 (see figure 1) so as to be arranged in contact on a flat surface of the bolt.

[0082] Other equivalent anti-unscrewing systems could still be used.

[0083] The attached figures depict a front part 2 having a 45° bevel (see for example figure 1).

[0084] This bevel can obviously not be included, thus having two sides that join together at 90 angular degrees.

Claims

1. A vice device (1) for locking the heating system (100, 200) to a superstructure (10) of a switch point with moveable point frog for high-speed trains, the device comprising:

- A front striker (2), configured to be applied to a slab (10') of the stock rail (10) of the said switch point, and a rear striker (4, 5) configured to be applied onto the web (10") of the same stock rail (10);

- Clamping elements (3, 30) connecting the front striker (2) to the rear striker (4, 5) and configured to enable the adjustment of the distance from one another, said clamping elements comprising a tie rod element (3), said tie rod element being in form of a rod (3) threaded at least in part and a clamping element (30) configured to be screwed onto the thread of said rod;

Characterized by the fact that said threaded rod is permanently fixed to the rear striker (4, 5) and it is connected in sliding manner with respect to the front striker (2), said front striker (2) comprising a longitudinal through channel (2') within which said rod (3) is inserted in sliding manner so that at least a threaded part of said rod protrudes from said channel thus enabling the application of the clamping element (30) onto said thread and with said front striker (2) shaped with a cavity (20) configured to house the shape of the slab of the stock rail to which it is applied, said rear striker (4, 5) being generally L-shaped comprising a lower part (4') fixed to the back of the tie rod (3) and an upper part (4") which stands from said lower part (4') so as to form a pressure surface (4") which pushes in use onto the surface of the web of the stock rail to which it is applied in use, the upper end of the said upper part (4") including a pressure element (5) suitable for exerting a pressure against the heating cables applied to the said stock rail.

2. A vice device (1), according to claim 1, wherein the shape of the said pressure element (5) has a complementary shape to the shape of the wireway (200) which contains in use the electrical cables applied to said stock rail (10).

3. A vice device (1), according to claim 1 or 2, wherein said pressure element (5) is S-shaped so as to retrace the shape of the wireway which contains the electrical cables and against which it pushes in use.

4. A vice device, according to claim 1, wherein said longitudinal through channel (2') is not threaded.

5. A vice device (1), according to claim 1, wherein said lower part (4') of the rear striker is welded to the back of the pivot (3).

6. A vice device (1), according to claim 3, wherein said clamping element (30) is a bolt or similar ones.

7. A vice device (1), according to one or more of the preceding claims, comprising anti-unscrewing elements (31).

8. A vice device, according to claim 1, wherein, on the back of the block (2), one or more through holes (2") are provided, for example two through holes (2"), for enabling the insertion of screws, for example Allen screws with a pointed end whose point pushes onto the back of the slab (10') for increasing the fastening constraint.

9. A heating assembly for heating the superstructure (10) of a switch point with moveable point frog for high-speed trains, the device comprising:

- At least an electrical cable (100) which can be supplied with electricity so as to produce heat for Joule effect;

- A vice device as per one or more of the preceding claims from 1 to 8.

10. An assembly, according to claim 9, comprising a wireway (200) within which the electrical cable is arranged.

11. A method for fastening electrical cables (100) for generating heat with anti-icing purpose, to the stock rail (10) of a switch point with moveable point frog for high-speed trains, the said stock rail comprising a slab (10') and a web (10") in the back, the method providing the fastening of said electrical cables (100) to the web through the application of a vice device (1), as per one or more of the preceding claims from 1 to 8, which pushes said cables against the surface of the web to which they are applied.

12. A method, according to claim 11, wherein said cables are applied to a suitable seat obtained in the web.

13. A method, according to claim 11 or 12, comprising the phase of applying a thermal grease in the application seat of said electrical cables and the subsequent arrangement of the cables.

14. A method, according to one or more of claims from 10 to 13, comprising the phase of applying a wireway (200) within which the cables are arranged and with said wireway which is pushed against the wall of the web (10") to which it is fastened through said application of the said vice device (1).

15. A method, according to one or more of the preceding claims from 10 to 14, wherein the application of said vice device (1) comprises the phases of:

- Application of the front part (2) of the said vice device so as to fasten the slab (10');

- Insertion of the pivot (3) of the said vice device under the slab so as to insert it into the channel (2') of the said front part;

- Bringing the striker (4) integral to the pivot (3) into abutment, making the pivot advance in the channel (2') so that the pressure element (5) of the striker (4) pushes onto the wireway;

- Clamping by applying the clamping element (30) to the end of the pivot protruding from the channel (2') from the front part.

Drawing